Characterization of the deviation to the ideality of concentrated actinide and lanthanide salt solutions: contribution of the Bimsa theory

International Nuclear Information System (INIS)

Ruas, A.

2006-03-01

The aim of this work is to describe the mean stoichiometric activity coefficients, osmotic coefficients or water activities of aqueous actinide nitrate salt solutions up to high concentration. These sets of data are required for a better control of the equilibria occurring in liquid-liquid extraction processes. Experimental acquisition of these thermodynamic properties, in the case of some actinide nitrates, is possible and was conducted before.But, many actinide salt solutions cannot be experimentally handled up to high concentration because of unstable oxidation state or very high radioactivity. As a consequence, a suitable predictive theory is necessary for the description of these nitrate salt solutions (such as Am (NO 3 ) 3 , Cm (NO 3 ) 3 ). The BIMSA ('Binding Mean Spherical Approximation') was chosen for this purpose. This theory, unlike other methods, uses a set of microscopic parameters that have some physical meaning, for the description of macroscopic thermodynamic properties (osmotic coefficients, activity coefficients).The following manuscript is divided by 4 chapters, corresponding to 4 articles accepted in the scientific journal 'Journal of Physical Chemistry'. Chapter 1 first reviews the basic thermodynamic concepts before describing the issues involved in acquiring actinides binary data. An approach based on the thermodynamic concept of simple solutions, the notion of fictive binary data, is described. Within this approach, the activity coefficient of an aqueous phase constituent depends on two parameters: the water activity of the system and total concentration of dissolved constituents. As a first application, new fictive binary data of uranyl nitrate are proposed from measurements on the ternary system UO 2 (NO 3 ) 2 /HNO 3 /H 2 O.Chapter 2 gives the main principles of the BIMSA theory. It shows also preliminary promising results obtained when modeling lanthanide(III) salt properties. Then, in chapter 3, two predictive capabilities of the theory

Ionic solubility and solutal advection governed augmented evaporation kinetics of salt solution pendant droplets

Science.gov (United States)

Jaiswal, Vivek; Harikrishnan, A. R.; Khurana, Gargi; Dhar, Purbarun

2018-01-01

The presence of dispersed inclusions is known to modify the interfacial characteristics in liquids by adsorption-desorption of the ions at interfaces. The present article reports the influencing role of dissolved ions in a polar fluid on its evaporation dynamics. The evaporation dynamics of pendant droplets of aqueous solutions of variant simple salts and concentrations have been experimentally studied. The presence of salts is observed to enhance the evaporation rate (obeying the classical D2 law), and the enhancement has been found to hold a direct proportionality to the concentration of the dissolved salt. Furthermore, it is observed that the degree of enhancement in the evaporation rate is also directly proportional to the solubility of the salt in question. The phenomenon is explained based on the chemical kinetics and thermodynamics of hydration of the ionic species in the polar fluid. The classical evaporation rate constant formulation is found to be inadequate in modeling the enhanced species transport. Additional probing via particle image velocimetry reveals augmented internal circulation within the evaporating salt based drops compared to pure water. Mapping the dynamic surface tension reveals that a salt concentration gradient is generated between the bulk and periphery of the droplet and it could be responsible for the internal advection cells visualized. A thermo-solutal Marangoni and Rayleigh convection based mathematical formulation has been put forward, and it is shown that the enhanced solute-thermal convection could play a major role in enhanced evaporation. The internal circulation mapped from experiments is found to be in good quantitative agreement with the model predictions. Scaling analysis further reveals that the stability of the solutal Marangoni convection surpasses the thermal counterpart with higher salt concentration and solubility. The present article sheds insight into the possible domineering role of conjugate thermohydraulic and

Preferential solvation, ion pairing, and dynamics of concentrated aqueous solutions of divalent metal nitrate salts

Science.gov (United States)

Yadav, Sushma; Chandra, Amalendu

2017-12-01

We have investigated the characteristics of preferential solvation of ions, structure of solvation shells, ion pairing, and dynamics of aqueous solutions of divalent alkaline-earth metal nitrate salts at varying concentration by means of molecular dynamics simulations. Hydration shell structures and the extent of preferential solvation of the metal and nitrate ions in the solutions are investigated through calculations of radial distribution functions, tetrahedral ordering, and also spatial distribution functions. The Mg2+ ions are found to form solvent separated ion-pairs while the Ca2+ and Sr2+ ions form contact ion pairs with the nitrate ions. These findings are further corroborated by excess coordination numbers calculated through Kirkwood-Buff G factors for different ion-ion and ion-water pairs. The ion-pairing propensity is found to be in the order of Mg(NO3) 2 lead to the presence of substantial dynamical heterogeneity in these solutions of strongly interacting ions. The current study helps us to understand the molecular details of hydration structure, ion pairing, and dynamics of water in the solvation shells and also of ion diffusion in aqueous solutions of divalent metal nitrate salts.

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

Experiments on the effect of sphagnum on the pH of salt solutions

Energy Technology Data Exchange (ETDEWEB)

Williams, K T; Thompson, T G

1936-01-01

Addition of sphagnum to salt solutions produced marked increases in the concentrations of the hydrogen ions, as measured both electrometrically and colorimetrically. The greater the concentration of the salt solution, the greater the increase in hydrogen ion concentration upon the addition of sphagnum. With a given salt concentration, the hydrogen ion concentration increased with increase in quantity of sphagnum added. The divalent cations produced greater increases in the hydrogen concentration than the monovalent cations for equal weights of sphagnum. Divalent anions, while showing an increase in hydrogen ions, upon the addition of sphagnum were far less effective in increasing the hydrogen ion concentrations. Sphagnum may be a useful reagent for regulating the acidity of salt solutions for many types of scientific work. It seems probable that the adsorption of metallic and hydroxyl ions explains, at least in part, the acidity of the water of sphagnum bogs.

Americium Separations from High-Salt Solutions Using Anion Exchange

International Nuclear Information System (INIS)

Barr, Mary E.; Jarvinen, Gordon D.; Stark, Peter C.; Chamberlin, Rebecca M.; Bartsch, Richard A.; Zhang, Z.Y.; Zhao, W.

2001-01-01

The aging of the US nuclear stockpile presents a number of challenges, including the increasing radioactivity of plutonium residues due to the ingrowth of 241 Am from the β-decay of 241 Pu. We investigated parameters that affect the sorption of Am onto anion-exchange resins from concentrated effluents derived from nitric acid processing of plutonium residues. These postevaporator wastes are nearly saturated solutions of acidic nitrate salts, and americium removal is complicated by physical factors, such as solution viscosity and particulates, as well as by the presence of large quantities of competing metals and acid. Single- and double-contact batch distribution coefficients for americium and neodymium from simple and complex surrogate solutions are presented. Varied parameters include the nitrate salt concentration and composition and the nitric acid concentration. We find that under these extremely concentrated conditions, Am(III) removal efficiencies can surpass 50% per contact. Distribution coefficients for both neodymium and americium are insensitive to solution acidity and appear to be driven primarily by low water activities of the solutions

Photoionization of Sodium Salt Solutions in a Liquid Jet

International Nuclear Information System (INIS)

Grieves, G. A.; Petrik, Nikolay G.; Herring-Captain, J.; Olanrewaju, B.; Aleksandrov, A.; Tonkyn, Russell G.; Barlow, Stephan E.; Kimmel, Gregory A.; Orlando, Thomas M.

2008-01-01

A liquid microjet was employed to examine the gas/liquid interface of aqueous sodium halide (Na+X-, X=Cl, Br, I) salt solutions. Laser excitation at 193 nm produced and removed cations of the form H+(H2O)n and Na+(H2O)m from liquid jet surfaces containing either NaCl, NaBr or NaI. The protonated water cluster yield varied inversely with increasing salt concentration, while the solvated sodium ion cluster yield varied by anion type. The distribution of H+(H2O)n at low salt concentration is identical to that observed from low-energy electron irradiated amorphous ice and the production of these clusters can be accounted for using a localized ionization/Coulomb expulsion model. Production of Na+(H2O)m is not accounted for by this model but requires ionization of solvation shell waters and a contact ion/Coulomb expulsion mechanism. The reduced yields of Na+(H2O)m from high concentration (10-2 and 10-1 M) NaBr and NaI solutions indicate a propensity for Br- and I- at the solution surfaces and interfaces. This is supported by the observation of multiphoton induced production and desorption of Br+ and I+ from the 10-2 and 10-1 M solution surfaces

Photoionization of Sodium Salt Solutions in a Liquid Jet

Energy Technology Data Exchange (ETDEWEB)

Grieves, G. A.; Petrik, Nikolay G.; Herring-Captain, J.; Olanrewaju, B.; Aleksandrov, A.; Tonkyn, Russell G.; Barlow, Stephan E.; Kimmel, Gregory A.; Orlando, Thomas M.

2008-06-05

A liquid microjet was employed to examine the gas/liquid interface of aqueous sodium halide (Na+X-, X=Cl, Br, I) salt solutions. Laser excitation at 193 nm produced and removed cations of the form H+(H2O)n and Na+(H2O)m from liquid jet surfaces containing either NaCl, NaBr or NaI. The protonated water cluster yield varied inversely with increasing salt concentration, while the solvated sodium ion cluster yield varied by anion type. The distribution of H+(H2O)n at low salt concentration is identical to that observed from low-energy electron irradiated amorphous ice and the production of these clusters can be accounted for using a localized ionization/Coulomb expulsion model. Production of Na+(H2O)m is not accounted for by this model but requires ionization of solvation shell waters and a contact ion/Coulomb expulsion mechanism. The reduced yields of Na+(H2O)m from high concentration (10-2 and 10-1 M) NaBr and NaI solutions indicate a propensity for Br- and I- at the solution surfaces and interfaces. This is supported by the observation of multiphoton induced production and desorption of Br+ and I+ from the 10-2 and 10-1 M solution surfaces.

Preliminary study on lithium-salt aqueous solution blanket

International Nuclear Information System (INIS)

Yoshida, Hiroshi; Naruse, Yuji; Yamaoka, Mitsuaki; Ohara, Atsushi; Ono, Kiyoshi; Kobayashi, Shigetada.

1992-06-01

Aqueous solution blanket using lithium salts such as LiNO 3 and LiOH have been studied in the US-TIBER program and ITER conceptual design activity. In the JAERI/LANL collaboration program for the joint operation of TSTA (Tritium Systems Test Assembly), preliminary design work of blanket tritium system for lithium ceramic blanket, aqueous solution blanket and liquid metal blanket, have been performed to investigate technical feasibility of tritium demonstration tests using the TSTA. Detail study of the aqueous solution blanket concept have not been performed in the Japanese fusion program, so that this study was carried out to investigate features of its concept and to evaluated its technical problems. The following are the major items studied in the present work: (i) Neutronics of tritium breeding ratio and shielding performance Lithium concentration, Li-60 enrichment, beryllium or lead, composition of structural material/beryllium/solution, heavy water, different lithium-salts (ii) Physicochemical properties of salts Solubility, corrosion characteristics and compatibility with structural materials, radiolysis (iii) Estimation of radiolysis in ITER aqueous solution blanket. (author)

A Study of Analytical Solution for the Special Dissolution Rate Model of Rock Salt

Directory of Open Access Journals (Sweden)

Xin Yang

2017-01-01

Full Text Available By calculating the concentration distributions of rock salt solutions at the boundary layer, an ordinary differential equation for describing a special dissolution rate model of rock salt under the assumption of an instantaneous diffusion process was established to investigate the dissolution mechanism of rock salt under transient but stable conditions. The ordinary differential equation was then solved mathematically to give an analytical solution and related expressions for the dissolved radius and solution concentration. Thereafter, the analytical solution was fitted with transient dissolution test data of rock salt to provide the dissolution parameters at different flow rates, and the physical meaning of the analytical formula was also discussed. Finally, the influential factors of the analytical formula were investigated. There was approximately a linear relationship between the dissolution parameters and the flow rate. The effects of the dissolution area and initial volume of the solution on the dissolution rate equation of rock salt were computationally investigated. The results showed that the present analytical solution gives a good description of the dissolution mechanism of rock salt under some special conditions, which may provide a primary theoretical basis and an analytical way to investigate the dissolution characteristics of rock salt.

Regularities of radium coprecipitation with barium sulfate from salt solutions

International Nuclear Information System (INIS)

Kudryavskij, Yu.P.; Rakhimova, O.V.

2007-01-01

Coprecipitation of radium with barium sulfate from highly concentrated NaCl solutions is studied, including the effects of the initial solution composition, alkaline reagent (CaO, NaOH), supporting electrolyte (NaCl) concentration, and pH. The process is promoted by high NaCl concentration in the initial solution, which is due to structural transformation and change in the sorption activity of the BaSO 4 precipitate in salt solutions. The results obtained were applied to recovery of radium from process solutions during the development and introduction of improved procedure for disinfection and decontamination of waste yielded by chlorination of loparite concentrates [ru

EFFECTS OF INORGANIC SALT SOLUTION ON SOME PROPERTIES OF COMPACTED CLAY LINERS

Directory of Open Access Journals (Sweden)

KHALID R. MAHMOOD AL-JANABI

2017-12-01

Full Text Available Processed and natural clays are widely used to create impermeable liners in solid waste disposal landfills. The engineering properties of clay liners can be significantly affected by the leachate from the waste mass. In this study, the effect of inorganic salt solutions will be investigated. These solutions used at different concentrations. Two type of inorganic salt MnSO4 and FeCl3 are used at different concentration 2%,5%, 10%. Clay used in this study was the CL- clay (kaolinite. The results show that the consistency limits and unconfined compressive strength increased as the concentration of salts increased. While the permeability tends to decrease as salt concentration increased. Also, the compression index decreases as the concentration increased from 2% to 5%. The swelling index tends to increase slightly as the concentration of MnSO4 increased, while its decrease as the concentration of FeCl3. In this paper, it is aimed to investigate the performance of compacted clay liner exposed to the certain chemicals generated by the leachate and their effects on the geotechnical properties of compacted clay liner such consistency limits, permeability coefficient, compressibility characteristics and unconfined compressive strength.

Density Fluctuation in Aqueous Solutions and Molecular Origin of Salting-Out Effect for CO2

International Nuclear Information System (INIS)

Ho, Tuan Anh; Ilgen, Anastasia

2017-01-01

Using molecular dynamics simulation, we studied the density fluctuations and cavity formation probabilities in aqueous solutions and their effect on the hydration of CO 2 . With increasing salt concentration, we report an increased probability of observing a larger than the average number of species in the probe volume. Our energetic analyses indicate that the van der Waals and electrostatic interactions between CO 2 and aqueous solutions become more favorable with increasing salt concentration, favoring the solubility of CO 2 (salting in). However, due to the decreasing number of cavities forming when salt concentration is increased, the solubility of CO 2 decreases. The formation of cavities was found to be the primary control on the dissolution of gas, and is responsible for the observed CO 2 salting-out effect. Finally, our results provide the fundamental understanding of the density fluctuation in aqueous solutions and the molecular origin of the salting-out effect for real gas.

Solubility of pllutonium in alkaline salt solutions

International Nuclear Information System (INIS)

Hobbs, D.T.; Edwards, T.B.

1993-01-01

Plutonium solubility data from several studies have been evaluated. For each data set, a predictive model has been developed where appropriate. In addition, a statistical model and corresponding prediction intervals for plutonium solubility as a quadratic function of the hydroxide concentration have been developed. Because of the wide range of solution compositions, the solubility of plutonium can vary by as much as three orders of magnitude for any given hydroxide concentration and still remain within the prediction interval. Any nuclear safety assessments that depend on the maximum amount of plutonium dissolved in alkaline salt solutions should use concentrations at least as great as the upper prediction limits developed in this study. To increase the confidence in the prediction model, it is recommended that additional solubility tests be conducted at low hydroxide concentrations and with all of the other solution components involved. To validate the model for application to actual waste solutions, it is recommended that the plutonium solubilities in actual waste solutions be determined and compared to the values predicted by the quadratic model

Decondensation behavior of DNA chains induced by multivalent cations at high salt concentrations: Molecular dynamics simulations and experiments

International Nuclear Information System (INIS)

Jiang Yang-Wei; Zhang Lin-Xi; Ran Shi-Yong; He Lin-Li; Wang Xiang-Hong

2015-01-01

Using molecular dynamics simulations and atomic force microscopy (AFM), we study the decondensation process of DNA chains induced by multivalent cations at high salt concentrations in the presence of short cationic chains in solutions. The typical simulation conformations of DNA chains with varying salt concentrations for multivalent cations imply that the concentration of salt cations and the valence of multivalent cations have a strong influence on the process of DNA decondensation. The DNA chains are condensed in the absence of salt or at low salt concentrations, and the compacted conformations of DNA chains become loose when a number of cations and anions are added into the solution. It is explicitly demonstrated that cations can overcompensate the bare charge of the DNA chains and weaken the attraction interactions between the DNA chains and short cationic chains at high salt concentrations. The condensation-decondensation transitions of DNA are also experimentally observed in mixing spermidine with λ-phage DNA at different concentrations of NaCl/MgCl 2 solutions. (paper)

On change of iodobenzene electroreduction mechanism with change of tetraethylammonium salts concentration

International Nuclear Information System (INIS)

Majranovskij, S.G.; Rubinskaya, T.Ya.; Proskurovskaya, I.V.

1975-01-01

The effect of the nature and concentration of tetraethylammonium salt on the mechanism of electroreduction of iodobenzene at the mercury electrode was studied. For this purpose a microelectrolysis of iodobenzene solution was carried out with a subsequent chromatographic analysis of the yield products (with tetraethylammonium bromide as an indifferent electrolyte). Diphenylmercury was found on the background of tetraethylammonium salts at 0.08 to 0.2M concentrations among the electrolysis products besides the main product-benzene. At 0.01 and 1M salt concentrations even traces of diphenylmercury weren't detected. The diphenyl mercury content somewhat increases, if the electrolysis is conducted at the potentials of the startrise of the iodobenzene reduction wave, i. e. at E=-1.45V. Thus, the change of tetraethylammonium salt concentration may partially alter the iodobenzene reduction mechanism

Solution, thermal and optical properties of bis(pyridinium salt)s as ionic liquids

International Nuclear Information System (INIS)

Jo, Tae Soo; Koh, Jung Jae; Han, Haesook; Bhowmik, Pradip K.

2013-01-01

Bis(pyridinium salt)s containing different alkyl chain lengths and various organic counterions were prepared by the ring-transmutation reaction of bis(pyrylium tosylate) with aliphatic amines in dimethyl sulfoxide at 130–135 °C for 18 h and their tosylate counterions were exchanged to other anions such as triflimide, methyl orange, and dioctyl sulfosuccinate by the metathesis reaction in a common organic solvent. Their chemical structures were established by using 1 H, 19 F, and 13 C NMR spectra. The thermal properties of bis(pyridinium salt)s were studied by DSC and TGA measurements. Some of the dicationic salts provided low melting points below 100 °C and some of them displayed amorphous properties. Polarized optical microscopy studies revealed the crystal structures prior to melting temperatures in some cases. Their optical properties were examined by using UV–Vis and photoluminescent spectrometers; and they emitted blue light both in the solution and solid states regardless of their microstructures, counterions, and the polarity of organic solvents. However, most of these salts exhibited hypsochromic shifts in their emission peaks in the solid state when compared with those of their solution spectra. Due to unique properties of methyl orange anion as a pH indicator, two of the salts showed different color change in varying concentrations of triflic acid in common organic solvents, demonstrating their potential use as an acid sensor in methanol, acetonitrile and acetone. Highlights: ► Luminescent dicationic salts were synthesized by ring-transmutation and metathesis reactions. ► Thermal and optical properties of dicationic salts are affected by the size of anion structures. ► Due to the methyl orange counterions, some dicationic salts showed pH- sensing property

Nonmetal-metal transition in metal–molten-salt solutions

NARCIS (Netherlands)

Silvestrelli, P.-L.; Alavi, A.; Parrinello, M.; Frenkel, D.

1996-01-01

The method of ab initio molecular dynamics, based on finite-temperature density-functional theory, is used to study the nonmetal-metal transition in two different metal–molten-salt solutions, Kx(KCl)1-x and Nax(NaBr)1-x. As the excess metal concentration is increased the electronic density becomes

Solubility and speciation of actinides in salt solutions and migration experiments of intermediate level waste in salt formations

International Nuclear Information System (INIS)

1986-01-01

A comprehensive study into the solubility of the actinides americium and plutonium in concentrated salt solutions, the release of radionuclides from various forms of conditioned ILW and the migration behaviour of these nuclides through geological material specific to the Gorleben site in Lower Saxony is described. A detailed investigation into the characterization of four highly concentrated salt solutions in terms of their pH, Eh, inorganic carbon contents and their densities is given and a series of experiments investigating the solubility of standard americium(III) and plutonium(IV) hydroxides in these solutions is described. Transuranic mobility studies for solutions derived from the standard hydroxides through salt and sand have shown the presence of at least two types of species present of widely differing mobility; one migrating with approximately the same velocity as the solvent front and the other strongly retarded. Actinide mobility data are presented and discussed for leachates derived from the simulated ILW in cement and data are also presented for the migration of the fission products in leachates derived from real waste solidified in cement and bitumen. Relatively high plutonium mobilities were observed in the case of the former and in the case of the real waste leachates, cesium was found to be the least retarded. The sorption of ruthenium was found to be largely associated with the insoluble residues of the natural rock salt rather than the halite itself. (orig./RB)

Hydration patterns and salting effects in sodium chloride solution.

Science.gov (United States)

Li, Weifeng; Mu, Yuguang

2011-10-07

The salting effects of 2M sodium chloride electrolyte are studied based on a series of model solutes with properties ranging from hydrophobic to hydrophilic. Generally, hydrophobic solutes will be salted out and hydrophilic solutes will be salted in by NaCl solution. The solvation free energy changes are highly correlated with Kirkwood-Buff integrals. The underlying mechanism resorts to the preferential binding of ions and water to solutes. Our results demonstrate that the salting effect not only depends on the salt's position in Hofmeister series, but also on the solutes' specifics. Taking the hydration free energies of solutes and ions as independent variables, a schematic diagram of salting effects is suggested. The resolved multifaceted salting effects rely on the sensitive balance of the tripartite interaction among solutes, ions, and water. © 2011 American Institute of Physics

Ammonia complexes of metals in aqueous solutions with high concentrations of ammonia

International Nuclear Information System (INIS)

Padar, T.G.; Novikov, L.K.; Stupko, T.V.; Isaev, I.D.; Pashkov, G.L.; Mironov, V.E.

1991-01-01

Potentiometric method, glass electrodes and Bierrum function were used to study the formation of ammonia complexes of magnesium, calcium, cadmium, zinc, copper(2) and silver in 2.0 mol/dm 3 aqueous solutions of ammonia nitrate with 0-18 mol/dm 3 ammonia concentrations at 25.0 deg C. Step constants of stability of studied complexes were calculated and their compositions were determined with account of nonideal character of aqueous-salt solutions with ammonia concentrations above 1.0 mol/dm 3 . Values of correction effects on salting out ammonia action for Bierrum function in solutions with 1.0-18 mol/dm 3 ammonia concentrations were found

Spectroscopic Characterization of HAN-Based Liquid Gun Propellants and Nitrate Salt Solutions

Science.gov (United States)

1989-01-15

spectra were recorded of bubbles of a concentrated aqueous nitrate solution, mineral oil, and an aqueous surfactant solution. Polymethacrylic acid ...FTIR spectra of droplets of a concentrated aqueous nitrate salt based solution (LGP1845), of solid particles cf polymethacrylic acid packing IO, 3... polymethacrylic acid low density packing foam cut to a 3x4 mnn rectangle was levitated with a low acoustic power. The sample was easily I positioned in the

Salt weathering in Egyptian limestone after laboratory simulations with continuous flow of salt solutions at different temperatures

Science.gov (United States)

Aly, Nevin; Gomez-Heras, Miguel; Hamed, Ayman; Alvarez de Buergo, Monica

2013-04-01

weathering in Egyptian limestone after laboratory simulations with continuous flow of salt solutions at different temperatures Nevin Aly Mohamed (1), Miguel Gomez - Heras(2), Ayman Hamed Ahmed (1), and Monica Alvarez de Buergo(2). (1) Faculty of Pet. & Min. Engineering- Suez Canal University, Suez, Egypt, (2) Instituto de Geociencias (CSIC-UCM) Madrid. Spain. Limestone is one of the most frequent building stones in Egypt and is used since the time of ancient Egyptians and salt weathering is one of the main threats to its conservation. Most of the limestone used in historical monuments in Cairo is a biomicrite extracted from the Mid-Eocene Mokattam Group. During this work, cylindrical samples (2.4 cm diameter and approx. 4.8 cm length) were subjected, in a purpose-made simulation chamber, to simulated laboratory weathering tests with fixed salt concentration (10% weight NaCl solution), at different temperatures, which were kept constant throughout each test (10, 20, 30, 40 oC). During each test, salt solutions flowed continuously imbibing samples by capilarity. Humidity within the simulation chamber was reduced using silica gel to keep it low and constant to increase evaporation rate. Temperature, humidity inside the simulation chamber and samples weight were digitally monitored during each test. Results show the advantages of the proposed experimental methodology using a continuous flow of salt solutions and shed light on the effect of temperature on the dynamics of salt crystallization on and within samples. Research funded by mission sector of high education ministry, Egypt and Geomateriales S2009/MAT-1629.

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.

Free Energies by Thermodynamic Integration Relative to an Exact Solution, Used to Find the Handedness-Switching Salt Concentration for DNA.

Science.gov (United States)

Berryman, Joshua T; Schilling, Tanja

2013-01-08

Sets of free energy differences are useful for finding the equilibria of chemical reactions, while absolute free energies have little physical meaning. However finding the relative free energy between two macrostates by subtraction of their absolute free energies is a valuable strategy in certain important cases. We present calculations of absolute free energies of biomolecules, using a combination of the well-known Einstein molecule method (for treating the solute) with a conceptually related method of recent genesis for computing free energies of liquids (to treat the solvent and counterions). The approach is based on thermodynamic integration from a detailed atomistic model to one which is simplified but analytically solvable, thereby giving the absolute free energy as that of the tractable model plus a correction term found numerically. An example calculation giving the free energy with respect to salt concentration for the B- and Z-isomers of all-atom duplex DNA in explicit solvent and counterions is presented. The coexistence salt concentration is found with unprecedented accuracy.

Effect of salt solutions on the radiosensitivity of mammalian cells as a function of the state of adhesion and the water structure

Energy Technology Data Exchange (ETDEWEB)

Moggach, P G; Lepock, J R; Kruuv, J [Waterloo Univ., Ontario (Canada). Dept. of Physics

1979-11-01

The radiation isodose survival curve of attached Chinese hamster (V79) cells, subjected to a wide concentration range of salt or sucrose solutions, was characterized by two maxima separated by a minimum. Cells were radioprotected at the maxima (high and low hypertonic salt concentrations) while they were radiosensitized at the minimum (intermediate hypertonic salt concentrations). Both cations and anions could alter the cellular radiosensitivity above and beyond the (osmotic) effect observed for cells treated with sucrose solutions. However, the basic curve shape, except in the case of sulphate salts, remained the same. When these experiments were repeated with single cells in suspension, the isodose survival curve was quite different in that high salt concentrations did not protect cells in suspension unlike the case with attached cells. The curve shape was also altered in that the second maximum was absent with many salt solutions. When multicellular spheroids were used for these experiments, the data resembled those for single cell suspensions rather than for attached cells. The radiation survival data for cells in suspension in salt solutions correlated with water proton spin lattice relaxation time (T/sub 1/) and, in hypo- and iso-tonic solutions, with cell volume.

Corrosion of carbon steel in saturated high-level waste salt solutions

International Nuclear Information System (INIS)

Wiersma, B.J.; Parish, W.R.

1997-01-01

High level waste stored as crystallized salts is to be removed from carbon steel tanks by water dissolution. Dissolution of the saltcake must be performed in a manner which will not impact the integrity of the tank. Corrosion testing was performed to determine the amount of corrosion inhibitor that must be added to the dissolution water in order to ensure that the salt solution formed would not induce corrosion degradation of the tank materials. The corrosion testing performed included controlled potential slow strain rate, coupon immersion, and potentiodynamic polarization tests. These tests were utilized to investigate the susceptibility of the cooling coil material to stress corrosion cracking in the anticipated environments. No evidence of SCC was observed in any of the tests. Based on these results, the recommended corrosion requirements were that the temperature of the salt solution be less than 50 degrees C and that the minimum hydroxide concentration be 0.4 molar. It was also recommended that the hydroxide concentration not stay below 0.4 molar for longer than 45 days

Correlation of high-temperature stability of alpha-chymotrypsin with 'salting-in' properties of solution.

Science.gov (United States)

Levitsky VYu; Panova, A A; Mozhaev, V V

1994-01-15

A correlation between the stability of alpha-chymotrypsin against irreversible thermal inactivation at high temperatures (long-term stability) and the coefficient of Setchenov equation as a measure of salting-in/out efficiency of solutes in the Hofmeister series has been found. An increase in the concentration of salting-in solutes (KSCN, urea, guanidinium chloride, formamide) leads to a many-fold decrease of the inactivation rate of the enzyme. In contrast, addition of salting-out solutes has a small effect on the long-term stability of alpha-chymotrypsin at high temperatures. The effects of solutes are additive with respect to their salting-in/out capacities; the stabilizing action of the solutes is determined by the calculated Setchenov coefficient of solution. The correlation is explained by a solute-driven shift of the conformational equilibrium between the 'low-temperature' native and the 'high-temperature' denatured forms of the enzyme within the range of the kinetic scheme put forward in the preceding paper in this journal: irreversible inactivation of the high-temperature form proceeds much more slowly compared with the low-temperature form.

Extraction of lanthanide(III) nitrates from water-salt solutions with n.-octanol

International Nuclear Information System (INIS)

Keskinov, V.A.; Kudrova, A.V.; Valueva, O.V.; Pyartman, A.K.

2004-01-01

Extraction of lanthanide(III) nitrates (Ln=La-Nd, Sm-Gd) from aqueous-salt solutions at 298.15 K was studied using solution of n.-octanol, its concentration 6.31 mol/l. It was ascertained that at Ln(NO 3 ) 3 concentration in aqueous phase below 0.6 mol/l, there is actually no extraction. At higher concentrations of nitrates in aqueous phase the content of lanthanides(III) in organic phase increases in the series La-Gd. Isotherms of extraction were ascertained, its phase equilibria being described mathematically. It is shown that extraction of lanthanide(III) nitrates with n.-octanol should be realized from concentrated aqueous solutions [ru

Concentrated aqueous sodium chloride solution in clays at thermodynamic conditions of hydraulic fracturing: Insight from molecular dynamics simulations

Science.gov (United States)

Svoboda, Martin; Lísal, Martin

2018-06-01

To address a high salinity of flow-back water during hydraulic fracturing, we use molecular dynamics (MD) simulations and study the thermodynamics, structure, and diffusion of concentrated aqueous salt solution in clay nanopores. The concentrated solution results from the dissolution of a cubic NaCl nanocrystal, immersed in an aqueous NaCl solution of varying salt concentration and confined in clay pores of a width comparable to the crystal size. The size of the nanocrystal equals to about 18 Å which is above a critical nucleus size. We consider a typical shale gas reservoir condition of 365 K and 275 bar, and we represent the clay pores as pyrophyllite and Na-montmorillonite (Na-MMT) slits. We employ the Extended Simple Point Charge (SPC/E) model for water, Joung-Cheatham model for ions, and CLAYFF for the slit walls. We impose the pressure in the normal direction and the resulting slit width varies from about 20 to 25 Å when the salt concentration in the surrounding solution increased from zero to an oversaturated value. By varying the salt concentration, we observe two scenarios. First, the crystal dissolves and its dissolution time increases with increasing salt concentration. We describe the dissolution process in terms of the number of ions in the crystal, and the crystal size and shape. Second, when the salt concentration reaches a system solubility limit, the crystal grows and attains a new equilibrium size; the crystal comes into equilibrium with the surrounding saturated solution. After crystal dissolution, we carry out canonical MD simulations for the concentrated solution. We evaluate the hydration energy, density profiles, orientation distributions, hydrogen-bond network, radial distribution functions, and in-plane diffusion of water and ions to provide insight into the microscopic behaviour of the concentrated aqueous sodium chloride solution in interlayer galleries of the slightly hydrophobic pyrophyllite and hydrophilic Na-MMT pores.

Salt-assisted and salt-suppressed sol-gel transitions of methylcellulose in water.

Science.gov (United States)

Xu, Y; Wang, C; Tam, K C; Li, L

2004-02-03

The effects of various salts on the sol-gel transition of aqueous methylcellulose (MC) solutions have been studied systematically by means of a micro differential scanning calorimeter. It was found that the heating process was endothermic while the cooling process was exothermic for both MC solutions with and without salts. The addition of salts did not change the patterns of gelation and degelation of MC. However, the salts could shift the sol-gel transition and the gel-sol transition to lower or higher temperatures from a pure MC solution, depending on the salt type. These opposite effects were termed the salt-assisted and salt-suppressed sol-gel transitions. Either the salt-assisted transition or the salt-suppressed sol-gel transition was a function of salt concentration. In addition, each salt was found to have its own concentration limit for producing a stable aqueous solution of MC at a given concentration of MC, which was related to the anionic charge density of the salt. Cations were proved to have weaker effects than anions. The "salt-out strength", defined as the salt effect per mole of anion, was obtained for each anion studied. The thermodynamic mechanisms involved in the salt-assisted and salt-suppressed sol-gel transitions are discussed.

Quenching characteristics of bathocuproinedisulfonic acid, disodium salt in aqueous solution and copper sulfate plating solution

Science.gov (United States)

Koga, Toshiaki; Hirakawa, Chieko; Takeshita, Michinori; Terasaki, Nao

2018-04-01

Bathocuproinedisulfonic acid, disodium salt (BCS) is generally used to detect Cu(I) through a color reaction. We newly found BCS fluorescence in the visible blue region in an aqueous solution. However, the fluorescence mechanism of BCS is not well known, so we should investigate its fundamental information. We confirmed that the characteristics of fluorescence are highly dependent on the molecular concentration and solvent properties. In particular, owing to the presence of the copper compound, the fluorescence intensity extremely decreases. By fluorescence quenching, we observed that a copper compound concentration of 10-6 mol/L or less could easily be measured in an aqueous solution. We also observed BCS fluorescence in copper sulfate plating solution and the possibility of detecting monovalent copper by fluorescence reabsorption.

Role of salt concentration in blend polymer for energy storage conversion devices

Energy Technology Data Exchange (ETDEWEB)

Arya, Anil; Sharma, A. L., E-mail: alsharmaiitkgp@gmail.com [Centre for Physical Sciences, Central university of Punjab, Bathinda-151001. INDIA (India); Sadiq, M. [Department of Physics, I.I.T. (BHU), Varanasi-India (India)

2016-05-06

Solid Polymer Electrolytes (SPE) are materials of considerable interest worldwide, which serves dual purpose of electrolyte and separator between electrode compartments in renewable energy conversion/storage devices such as; high energy density batteries, electrochromic display devices, and supercapacitors. Polymer blend electrolytes are prepared for various concentration of salt (Ö/Li) with the constant ratio (0.5 gm) of each PEO and PAN polymers (blend polymer) using solution casting technique. Solid polymeric ionic conductor as a separator is the ultimate substitute to eliminate the drawback related to liquid and gel polymer ionic conductors. In the present work, solid polymer electrolyte film consisting of PEO, PAN and LiPF{sub 6} are examined for various concentration of lithium salt by keeping PEO/PAN blend ratio as a constant with a view to optimize the dominant salt concentration which could give the maximum conductivity at ambient temperature.

Ion exchange removal of technetium from salt solutions

International Nuclear Information System (INIS)

Walker, D.D.

1983-01-01

Ion exchange methods for removing technetium from waste salt solutions have been investigated by the Savannah River Laboratory (SRL). These experiments have shown: Commercially available anion exchange resins show high selectivity and capacity for technetium. In column runs, 150 column volumes of salt solution were passed through an ion exchange column before 50% 99 Tc breakthrough was reached. The technetium can be eluted from the resin with nitric acid. Reducing resins (containing borohydride) work well in simple hydroxide solutions, but not in simulated salt solutions. A mercarbide resin showed a very high selectivity for Tc, but did not work well in column operation

Salt-specific effects in lysozyme solutions

Directory of Open Access Journals (Sweden)

T. Janc

2016-03-01

Full Text Available The effects of additions of low-molecular-mass salts on the properties of aqueous lysozyme solutions are examined by using the cloud-point temperature, T_{cloud}, measurements. Mixtures of protein, buffer, and simple salt in water are studied at pH=6.8 (phosphate buffer and pH=4.6 (acetate buffer. We show that an addition of buffer in the amount above I_{buffer} = 0.6 mol dm^{-3} does not affect the T_{cloud} values. However, by replacing a certain amount of the buffer electrolyte by another salt, keeping the total ionic strength constant, we can significantly change the cloud-point temperature. All the salts de-stabilize the solution and the magnitude of the effect depends on the nature of the salt. Experimental results are analyzed within the framework of the one-component model, which treats the protein-protein interaction as highly directional and of short-range. We use this approach to predict the second virial coefficients, and liquid-liquid phase diagrams under conditions, where T_{cloud} is determined experimentally.

Inefficacy of osmotic backwash induced by sodium chloride salt solution in controlling SWRO membrane fouling

Science.gov (United States)

Farooque, A. Mohammed; Al-Jeshi, Subhi; Saeed, Mohamed O.; Alreweli, Ali

2014-12-01

A study was conducted to evaluate the efficacy of osmotic backwash induced by high salt (NaCl) concentration solution on feed side of seawater reverse osmosis (SWRO) membranes, online and offline, in controlling membrane fouling and therefore minimizing/eliminating the need for chemical cleaning. SWRO membranes were deliberately fouled by feeding seawater from an open intake located on the Arabian Gulf Coast without dosing chemicals. The fouled membranes were subjected to offline cleaning with the salt solution of up to 25 % concentration. Despite the partial removal of foulants from the membrane surface, SWRO membrane performance could not be restored, indicating the ineffectiveness of osmotic backwash in aiding offline salt cleaning. Similarly, online osmotic backwash was found to be not only ineffective in removing foulants from membrane surfaces but actually increased the fouling rate, as indicated by faster fouling rates compared to other cases. Although the driving force required for the osmotic backwash existed, the generated back flow proved to be insufficient to detach foulants from membrane surfaces. During the study period, the average SWRO membrane flux was maintained between 19 and 23 LMH, whereas the average generated back flow flux by high salt concentration solution was only 11 LMH, which was not adequate to remove foulants from membrane surfaces. Moreover, it seems that the membrane configuration as well as inherent microstructure of SWRO membrane places certain constraints on the osmotic backwash process and renders osmotic backwash ineffective in tackling SWRO membrane fouling. Hence, chemical cleaning is essential to restore SWRO membrane performance whenever fouling occurs, and the use of highly concentrated salt solution does not have any significant benefit. Membrane autopsy revealed only an insignificant accumulation of biofouling layer despite the absence of disinfection. However, it was shown that culturable biofilm bacteria species

Communication: Modeling of concentration dependent water diffusivity in ionic solutions: Role of intermolecular charge transfer

Energy Technology Data Exchange (ETDEWEB)

Yao, Yi; Berkowitz, Max L., E-mail: maxb@unc.edu, E-mail: ykanai@unc.edu; Kanai, Yosuke, E-mail: maxb@unc.edu, E-mail: ykanai@unc.edu [Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 (United States)

2015-12-28

The translational diffusivity of water in solutions of alkali halide salts depends on the identity of ions, exhibiting dramatically different behavior even in solutions of similar salts of NaCl and KCl. The water diffusion coefficient decreases as the salt concentration increases in NaCl. Yet, in KCl solution, it slightly increases and remains above bulk value as salt concentration increases. Previous classical molecular dynamics simulations have failed to describe this important behavior even when polarizable models were used. Here, we show that inclusion of dynamical charge transfer among water molecules produces results in a quantitative agreement with experiments. Our results indicate that the concentration-dependent diffusivity reflects the importance of many-body effects among the water molecules in aqueous ionic solutions. Comparison with quantum mechanical calculations shows that a heterogeneous and extended distribution of charges on water molecules around the ions due to ion-water and also water-water charge transfer plays a very important role in controlling water diffusivity. Explicit inclusion of the charge transfer allows us to model accurately the difference in the concentration-dependent water diffusivity between Na{sup +} and K{sup +} ions in simulations, and it is likely to impact modeling of a wide range of systems for medical and technological applications.

Separation and Concentration of Succinic Adic from Multicomponent Aqueous Solutions by Nanofiltration Technique

Directory of Open Access Journals (Sweden)

Antczak Jerzy

2014-06-01

Full Text Available This paper applies the determined suitability of nanofiltration (NF membrane separation for selective isolation and concentration of succinic acid from aqueous solutions which are post-fermentation multicomponent fluids. The study analyzed the influence of concentration and the pH of the separated solutions on the efficiency and selectivity of NF process that runs in a module equipped with a ceramic membrane. Moreover, the effect of applied trans-membrane pressure on the retention of succinic acid and sodium succinate has been studied. The investigations have shown that in the used NF module the retention of succinic acid salt is equal almost 50% in the case of a three-component model solution, although the degree of retention depends on both the transmembrane pressure and the initial concentration of separated salt.

The nonmetal-metal transition in solutions of metals in molten salts

International Nuclear Information System (INIS)

Tosi, M.P.

1997-04-01

Solutions of metals in molten salts present a rich phenomenology: localization of electrons in disordered ionic media, activated electron transport increasing with metal concentration towards a nonmetal-metal (NM-M) transition, and liquid-liquid phase separation. A brief review of progress in the study of these systems is given in this article, with main focus on the NM-M transition. After recalling the known NM-M behaviour of the component elements in the case of expanded fluid alkali metals and mercury and of solid halogens under pressure, the article focuses on liquid metal - molten salt solutions and traces the different NM-M behaviours of the alkalis in their halides and of metals added to polyvalent metal halides. (author). 51 refs, 2 figs

Extraction of lithium from neutral salt solutions with fluorinated. beta. -diketones

Energy Technology Data Exchange (ETDEWEB)

Seeley, F.G.; Baldwin, W.H.

1976-01-01

Lithium was selectively extracted from near-neutral aqueous solutions of alkali metal salts. The mechanism by which this was achieved involves the formation of the trioctylphosphine oxide adduct of a lithium chelate of a fluorinated ..beta..-diketone, which is then readily extractable into an organic diluent. High separation factors were obtained from sodium, potassium, rubidium, and cesium. The selectivity of the fluorinated ..beta..-diketones for lithium over the alkaline earths was found to be poor. A suggested general flowsheet for the recovery of lithium from a salt brine concentrate is included.

Extraction of lithium from neutral salt solutions with fluorinated β-diketones

International Nuclear Information System (INIS)

Seeley, F.G.; Baldwin, W.H.

1976-01-01

Lithium was selectively extracted from near-neutral aqueous solutions of alkali metal salts. The mechanism by which this was achieved involves the formation of the trioctylphosphine oxide adduct of a lithium chelate of a fluorinated β-diketone, which is then readily extractable into an organic diluent. High separation factors were obtained from sodium, potassium, rubidium, and cesium. The selectivity of the fluorinated β-diketones for lithium over the alkaline earths was found to be poor. A suggested general flowsheet for the recovery of lithium from a salt brine concentrate is included. (author)

Influence of the supporting salt concentration on the electrodeposition of ZnO/eosin Y hybrid films

Energy Technology Data Exchange (ETDEWEB)

Boeckler, C.; Oekermann, T. [Institute of Physical Chemistry and Electrochemistry, Leibniz University Hannover (Germany); Saruban, M.; Ichinose, K.; Yoshida, T. [Center of Innovative Photovoltaic Systems (CIPS), Environmental and Renewable Energy Systems (ERES) Division, Graduate School of Engineering, Gifu University (Japan)

2008-10-15

ZnO/eosin Y hybrid films were electrodeposited from O{sub 2}-saturated ZnCl{sub 2}-solution under variation of the concentration of the supporting salt KCl. The supporting salt concentration was found to have a significant influence on the amount of dye loading and the morphology of the ZnO/eosin Y films. By decreasing the supporting salt concentration to 0.01 M KCl, porous films with a high dye loading can be obtained at potentials of -0.8 V vs. SCE at low eosin Y concentrations in the electrodeposition bath, which usually only lead to porous films at potentials where eosin Y is reduced (<-0.9 V vs. SCE). (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Non-monotonic swelling of surface grafted hydrogels induced by pH and/or salt concentration

Science.gov (United States)

Longo, Gabriel S.; Olvera de la Cruz, Monica; Szleifer, I.

2014-09-01

We use a molecular theory to study the thermodynamics of a weak-polyacid hydrogel film that is chemically grafted to a solid surface. We investigate the response of the material to changes in the pH and salt concentration of the buffer solution. Our results show that the pH-triggered swelling of the hydrogel film has a non-monotonic dependence on the acidity of the bath solution. At most salt concentrations, the thickness of the hydrogel film presents a maximum when the pH of the solution is increased from acidic values. The quantitative details of such swelling behavior, which is not observed when the film is physically deposited on the surface, depend on the molecular architecture of the polymer network. This swelling-deswelling transition is the consequence of the complex interplay between the chemical free energy (acid-base equilibrium), the electrostatic repulsions between charged monomers, which are both modulated by the absorption of ions, and the ability of the polymer network to regulate charge and control its volume (molecular organization). In the absence of such competition, for example, for high salt concentrations, the film swells monotonically with increasing pH. A deswelling-swelling transition is similarly predicted as a function of the salt concentration at intermediate pH values. This reentrant behavior, which is due to the coupling between charge regulation and the two opposing effects triggered by salt concentration (screening electrostatic interactions and charging/discharging the acid groups), is similar to that found in end-grafted weak polyelectrolyte layers. Understanding how to control the response of the material to different stimuli, in terms of its molecular structure and local chemical composition, can help the targeted design of applications with extended functionality. We describe the response of the material to an applied pressure and an electric potential. We present profiles that outline the local chemical composition of the

Mössbauer spectroscopic studies of frozen aqueous solutions of Fe3+ salts

DEFF Research Database (Denmark)

Mørup, Steen; Knudsen, J. E.; Nielsen, M. K.

1976-01-01

Frozen aqueous solutions (FAS) of Fe3+ salts have been investigated by use of Mössbauer spectroscopy in order to study the conditions for formation of glasses. A general discussion of spin–spin relaxation in glasses is given, and we discuss how changes in the spin–spin relaxation time can...... be attributed to changes in the average separation between the iron ions. In the FeCl3–H2O system, it was found that homogeneous glasses are easily formed when the salt concentration is larger than 3.5 moles FeCl3 per 100 moles H2O. In more dilute samples, ice crystallizes during cooling, while the salt...

Evaporation of a sessile water drop and a drop of aqueous salt solution.

Science.gov (United States)

Misyura, S Y

2017-11-07

The influence of various factors on the evaporation of drops of water and aqueous salt solution has been experimentally studied. Typically, in the studies of drop evaporation, only the diffusive vapor transfer, radiation and the molecular heat conduction are taken into account. However, vapor-gas convection plays an important role at droplet evaporation. In the absence of droplet boiling, the influence of gas convection turns out to be the prevailing factor. At nucleate boiling, a prevailing role is played by bubbles generation and vapor jet discharge at a bubble collapse. The gas convection behavior for water and aqueous salt solution is substantially different. With a growth of salt concentration over time, the influence of the convective component first increases, reaches an extremum and then significantly decreases. At nucleate boiling in a salt solution it is incorrect to simulate the droplet evaporation and the heat transfer in quasi-stationary approximation. The evaporation at nucleate boiling in a liquid drop is divided into several characteristic time intervals. Each of these intervals is characterized by a noticeable change in both the evaporation rate and the convection role.

Potentiometric titration curves of aluminium salt solutions and its ...

African Journals Online (AJOL)

Potentiometric titration curves of aluminium salt solutions and its species conversion ... of aluminium salt solutions under the moderate slow rate of base injection. ... silicate radical, and organic acid radical on the titration curves and its critical ...

Adding salt to a surfactant solution: Linear rheological response of the resulting morphologies

Energy Technology Data Exchange (ETDEWEB)

Gaudino, Danila; Pasquino, Rossana, E-mail: r.pasquino@unina.it; Grizzuti, Nino [DICMaPI, Università degli Studi di Napoli Federico II, P.le Tecchio 80, 80125 Napoli (Italy)

2015-11-15

The micellar system composed of Cetylpyridinium Chloride-Sodium Salicylate (CPyCl-NaSal) in brine aqueous solutions has been studied by systematically changing the salt concentration, in order to investigate the rheology of the arising morphologies. In particular, the zero-shear viscosity and the linear viscoelastic response have been measured as a function of the NaSal concentration (with [CPyCl] = 100 mM). The Newtonian viscosity shows a nonmonotonic dependence upon concentration, passing through a maximum at NaSal/CPyCl ≈ 0.6, and eventually dropping at higher salt concentrations. The progressive addition of salt determines first a transition from a Newtonian to a purely Maxwell-like behavior as the length of the micelles significantly increases. Beyond the peak viscosity, the viscoelastic data show two distinct features. On the one hand, the main relaxation time of the system strongly decreases, while the plateau modulus remains essentially constant. Calculations based on the rheological data show that, as the binding salt concentration increases, there is a decrease in micelles breaking rate and a decrease in their average length. On the other hand, in the same concentration region, a low-frequency elastic plateau is measured. Such a plateau is considered as the signature of a tenuous, but persistent branched network, whose existence is confirmed by cryo-transmission electron microscopy images.

SOLUTION MINING IN SALT DOMES OF THE GULF COAST EMBAYMENT

Energy Technology Data Exchange (ETDEWEB)

Griswold, G. B.

1981-02-01

Following a description of salt resources in the salt domes of the gulf coast embayment, mining, particularly solution mining, is described. A scenario is constructed which could lead to release of radioactive waste stored in a salt dome via inadvertent solution mining and the consequences of this scenario are analyzed.

Water purification using organic salts

Science.gov (United States)

Currier, Robert P.

2004-11-23

Water purification using organic salts. Feed water is mixed with at least one organic salt at a temperature sufficiently low to form organic salt hydrate crystals and brine. The crystals are separated from the brine, rinsed, and melted to form an aqueous solution of organic salt. Some of the water is removed from the aqueous organic salt solution. The purified water is collected, and the remaining more concentrated aqueous organic salt solution is reused.

Ice crystallization in ultrafine water-salt aerosols: nucleation, ice-solution equilibrium, and internal structure.

Science.gov (United States)

Hudait, Arpa; Molinero, Valeria

2014-06-04

Atmospheric aerosols have a strong influence on Earth's climate. Elucidating the physical state and internal structure of atmospheric aqueous aerosols is essential to predict their gas and water uptake, and the locus and rate of atmospherically important heterogeneous reactions. Ultrafine aerosols with sizes between 3 and 15 nm have been detected in large numbers in the troposphere and tropopause. Nanoscopic aerosols arising from bubble bursting of natural and artificial seawater have been identified in laboratory and field experiments. The internal structure and phase state of these aerosols, however, cannot yet be determined in experiments. Here we use molecular simulations to investigate the phase behavior and internal structure of liquid, vitrified, and crystallized water-salt ultrafine aerosols with radii from 2.5 to 9.5 nm and with up to 10% moles of ions. We find that both ice crystallization and vitrification of the nanodroplets lead to demixing of pure water from the solutions. Vitrification of aqueous nanodroplets yields nanodomains of pure low-density amorphous ice in coexistence with vitrified solute rich aqueous glass. The melting temperature of ice in the aerosols decreases monotonically with an increase of solute fraction and decrease of radius. The simulations reveal that nucleation of ice occurs homogeneously at the subsurface of the water-salt nanoparticles. Subsequent ice growth yields phase-segregated, internally mixed, aerosols with two phases in equilibrium: a concentrated water-salt amorphous mixture and a spherical cap-like ice nanophase. The surface of the crystallized aerosols is heterogeneous, with ice and solution exposed to the vapor. Free energy calculations indicate that as the concentration of salt in the particles, the advance of the crystallization, or the size of the particles increase, the stability of the spherical cap structure increases with respect to the alternative structure in which a core of ice is fully surrounded by

The influence of polarizability and charge transfer on specific ion effects in the dynamics of aqueous salt solutions

Science.gov (United States)

Nguyen, Mary; Rick, Steven W.

2018-06-01

The diffusion rates for water molecules in salt solutions depend on the identity of the ions, as well as their concentration. Among the alkali metal ions, cesium and potassium increase and sodium strongly decreases the diffusion constant of water. The origin of the difference can be understood by examining the simulation results using different potential models. In this work, aqueous solutions of salts are simulated with a variety of models. Commonly used non-polarizable models, which otherwise reproduce many experimental properties, do not capture the trend in the diffusion constant, while models which include polarization and/or charge transfer interactions do. For the non-polarizable models, the diffusion constant decreases too strongly with salt concentration. The changes in the water diffusion constant with increasing salt concentration match the diffusion constant of the ion. The ion diffusion constant is dependent on the residence time for water in the ion solvation shell. The non-polarizable models over-estimate the residence time, relative to the translational diffusion constant and so tend to under-estimate the ion and water diffusion constants.

Temperature effects on geotechnical and hydraulic properties of bentonite hydrated with inorganic salt solutions

DEFF Research Database (Denmark)

Rashid, H. M. A.; Kawamoto, K.; Saito, T.

2015-01-01

© 2015, International Journal of GEOMATE. This study investigated the combined effect of temperature and single-species salt solutions on geotechnical properties (swell index and liquid limit) and hydraulic conductivity of bentonite applying different cation types, concentrations, and temperatures...

Influence of complexing on physicochemical properties of polymer-salt solutions

International Nuclear Information System (INIS)

Ostroushko, A.A.; Yushkova, S.M.; Koridze, N.V.; Skobkoreva, N.V.; Zhuravleva, L.I.; Palitskaya, T.A.; Antropova, S.V.; Ostroushko, I.P.; AN SSSR, Moscow

1993-01-01

Using the methods of spectrophotometry, viscosimetry, conductometry the influence of salt-polymer complexing processes on physicochemical prperties of aqueous solutions of yttrium, barium, copper nitrates and formates with polyvinyl alcohol was studied. Change of dynamic viscosity, specific electric conductivity of solutions in the process of complexing was shown. Thermal effects of salt-polymer interaction were measured. It is shown that decrease of transition temperature of polymer to plastic state in films, temperature and effective activation energy of salt decomposition is also connected with complexing. Effective values of surface tension on the boundary with air are measured. Coefficients of cation diffusion in polymer-salt solutions are estimated

Preservation of bovine hide using less salt with low concentration of antiseptic, part I: effectiveness of developed formulations

Science.gov (United States)

Bovine raw hides are commercially cured either with high salt concentration of about half the weight of actual hide or 95% saturated brine solution. This conventional technique is very popular due to the availability of common salt (sodium chloride) and its cost effective procedure but it generates ...

Investigation of complexing in solutions of salt mixture In(NO3)3-NaVO3

International Nuclear Information System (INIS)

Nakhodnova, A.N.; Listratenko, I.V.

1987-01-01

Spectrophotometry, conductometry and pH-metry are used to investigate properties and composition of the solid phases of isomolar series of In(NO 3 ) 3 -NaVO 3 salt mixture solutions and series of solutions having constant concentration of one of the components and varied of the other. Results of investigation are presented. It is stated that in the investigated solution series in weakly acid media HPA with the ratios [In 3+ ]:[V 5+ ] being equal to 11:1, 6:1, and 1:9, are formed. Composition of the complexes is mainly defined by the ratio of the components in In(NO 3 ) 3 and NaVO 3 salt mixture solutions and the medium acidity. Compounds of Na 2 OxIn 2 O 3 x2.5V 2 O 5 x8.5H 2 O and Cs 2 OxIn 2 O 3 x6V 2 O 5 x6.5H 2 O empirical formulae are separated. Results of IR spectroscopy, derivatography and X-ray phase analysis of the corresponding salts are presented

On the attenuation of X-rays and gamma-rays for aqueous solutions of salts

CERN Document Server

Teli, M T

1998-01-01

Disparities in the linear attenuation coefficients of X-rays and gamma rays for aqueous solutions of soluble salts arising from the nonequality of volume of the solution with the sum of volumes of its components are analysed and the mixture rule is reformulated. The disparities are illustrated for NaCl solution for concentrations c=0 to 1 gm/cm sup 3 which indicates that the mixture rule of Teli et al. works well within generally acceptable limits.

Characterization of the deviation to the ideality of concentrated actinide and lanthanide salt solutions: contribution of the Bimsa theory; Caracterisation de l'ecart a l'idealite de solutions concentrees de sels d'actinide et de lanthanide: contribution de la theorie Bimsa

Energy Technology Data Exchange (ETDEWEB)

Ruas, A

2006-03-15

The aim of this work is to describe the mean stoichiometric activity coefficients, osmotic coefficients or water activities of aqueous actinide nitrate salt solutions up to high concentration. These sets of data are required for a better control of the equilibria occurring in liquid-liquid extraction processes. Experimental acquisition of these thermodynamic properties, in the case of some actinide nitrates, is possible and was conducted before.But, many actinide salt solutions cannot be experimentally handled up to high concentration because of unstable oxidation state or very high radioactivity. As a consequence, a suitable predictive theory is necessary for the description of these nitrate salt solutions (such as Am (NO{sub 3}){sub 3}, Cm (NO{sub 3}){sub 3}). The BIMSA ('Binding Mean Spherical Approximation') was chosen for this purpose. This theory, unlike other methods, uses a set of microscopic parameters that have some physical meaning, for the description of macroscopic thermodynamic properties (osmotic coefficients, activity coefficients).The following manuscript is divided by 4 chapters, corresponding to 4 articles accepted in the scientific journal 'Journal of Physical Chemistry'. Chapter 1 first reviews the basic thermodynamic concepts before describing the issues involved in acquiring actinides binary data. An approach based on the thermodynamic concept of simple solutions, the notion of fictive binary data, is described. Within this approach, the activity coefficient of an aqueous phase constituent depends on two parameters: the water activity of the system and total concentration of dissolved constituents. As a first application, new fictive binary data of uranyl nitrate are proposed from measurements on the ternary system UO{sub 2}(NO{sub 3}){sub 2}/HNO{sub 3}/H{sub 2}O.Chapter 2 gives the main principles of the BIMSA theory. It shows also preliminary promising results obtained when modeling lanthanide(III) salt properties. Then

CO2 Capture from Flue Gas using Amino Acid Salt Solutions

DEFF Research Database (Denmark)

Lerche, Benedicte Mai; Stenby, Erling Halfdan; Thomsen, Kaj

2009-01-01

difficult. Amino acid salt solutions have emerged as an alternative to the alkanolamine solutions. A number of advantages make amino acid salt solutions attractive solvents for CO2 capture from flue gas. In the present study CO2 absorption in aqueous solutions of 0.5 M potassium glycinate and 0.5 M...

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.

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

Ion-exchange properties of cesium and strontium into zeolites from sodium salt solutions

International Nuclear Information System (INIS)

Kanno, Takuji; Hashimoto, Hiroyuki; Ohtani, Tozo.

1978-01-01

The ion-exchange properties of cesium and strontium into zeolite from sodium salt solution has been studied in zeolite A, zeolite X, zeolite Y, mordenite and clinoptilolite. The distribution of cesium into mordenite from about 1 -- 2 M sodium chloride and sodium hydroxide solutions is considerably larger than that into zeolite A. The distribution coefficient for 2 M solution of sodium salts was about 300. Therefore, the separation of cesium from sodium salt solution is possible by using mordenite. The distribution of strontium into zeolites form 1 -- 2 M solutions of sodium chloride and sodium nitrate were in the order of zeolite A>zeolite X>zeolite Y asymptoticaly equals mordenite. The distribution coefficient of 230 was obtained for 1 M solutions of sodium salts. The anion in solutions had no effect on the distribution of cesium and strontium into zeolite from sodium salt solution. (author)

Influence of water and salt solutions on UVB irradiation of normal skin and psoriasis

International Nuclear Information System (INIS)

Boer, J.; Schothorst, A.A.; Boom, B.; Suurmond, D.; Hermans, J.

1982-01-01

The influence of tap-water (TW) and salt solutions on the minimal erythema dose (MED) was investigated for normal human skin and uninvolved skin of psoriasis patients. MED (UVB) determinations on the forearm revealed that: (1) the MED definitely decreases whenever the arm is immersed in TW or NaCl solutions with a low concentration (4%) prior to UVB exposure, whereas almost saturated NaCl solution (26%), as well as locum Dead Sea water (LDSW), do not produce a change in the MED, and (2) the decrease in MED obtained by wetting the skin with TW was no longer present when the skin was allowed to dry for 20 min. A decrease in water uptake by skin (in vivo) and by callus (in vitro) was found as the salt concentration of the external solution increased. It is proposed that water taken up by the skin plays an important role in the sensitivity of the skin to UVB exposure. Bathing in TW or 4% NaCl prior to UVB exposure offered a slight to moderate improvement in psoriasis over UVB irradiation alone. Finally, it was shown that there is no obvious difference in clearance of the psoriatic skin between a bath in TW, 4% NaCl, or LDSW prior to UVB exposure. (orig.)

Effects of basal media, salt concentrations, antioxidant supplements ...

African Journals Online (AJOL)

antioxidants than MS, LS and D basal media. Five different levels of N6 medium salts (10, 30, 50, 70 and 100%) were tested, and the highest transformation efficiency was 15.9% under a 50% salt concentration, followed by 6.4% transformation efficiency with 70 and 3.2% under 100% salt conditions. More than 95% of ...

Influence of salt concentration and topographical position on water ...

African Journals Online (AJOL)

Water resource quality (WRQ) is affected by salt concentration and topographical position. Indeed, an increase in salt concentration, which decreases water availability for animal and plant nutrition, and lower altitude, which diminishes the potential for production of hydropower, negatively affects WRQ. Therefore, it is useful ...

Modeling Solute Thermokinetics in LiCI-KCI Molten Salt for Nuclear Waste Separation

Energy Technology Data Exchange (ETDEWEB)

Morgan, Dane; Eapen, Jacob

2013-10-01

Recovery of actinides is an integral part of a closed nuclear fuel cycle. Pyrometallurgical nuclear fuel recycling processes have been developed in the past for recovering actinides from spent metallic and nitride fuels. The process is essentially to dissolve the spent fuel in a molten salt and then extract just the actinides for reuse in a reactor. Extraction is typically done through electrorefining, which involves electrochemical reduction of the dissolved actinides and plating onto a cathode. Knowledge of a number of basic thermokinetic properties of salts and salt-fuel mixtures is necessary for optimizing present and developing new approaches for pyrometallurgical waste processing. The properties of salt-fuel mixtures are presently being studied, but there are so many solutes and varying concentrations that direct experimental investigation is prohibitively time consuming and expensive (particularly for radioactive elements like Pu). Therefore, there is a need to reduce the number of required experiments through modeling of salt and salt-fuel mixture properties. This project will develop first-principles-based molecular modeling and simulation approaches to predict fundamental thermokinetic properties of dissolved actinides and fission products in molten salts. The focus of the proposed work is on property changes with higher concentrations (up to 5 mol%) of dissolved fuel components, where there is still very limited experimental data. The properties predicted with the modeling will be density, which is used to assess the amount of dissolved material in the salt; diffusion coefficients, which can control rates of material transport during separation; and solute activity, which determines total solubility and reduction potentials used during electrorefining. The work will focus on La, Sr, and U, which are chosen to include the important distinct categories of lanthanides, alkali earths, and actinides, respectively. Studies will be performed using LiCl-KCl salt

G eobacter sp. SD-1 with enhanced electrochemical activity in high-salt concentration solutions

KAUST Repository

Sun, Dan; Call, Douglas; Wang, Aijie; Cheng, Shaoan; Logan, Bruce E.

2014-01-01

© 2014 Society for Applied Microbiology and John Wiley & Sons Ltd. Summary: An isolate, designated strain SD-1, was obtained from a biofilm dominated by Geobacter sulfurreducens in a microbial fuel cell. The electrochemical activity of strain SD-1 was compared with type strains, G.sulfurreducensPCA and Geobacter metallireducensGS-15, and a mixed culture in microbial electrolysis cells. SD-1 produced a maximum current density of 290±29Am-3 in a high-concentration phosphate buffer solution (PBS-H, 200mM). This current density was significantly higher than that produced by the mixed culture (189±44Am-3) or the type strains (<70Am-3). In a highly saline water (SW; 50mM PBS and 650mM NaCl), current by SD-1 (158±4Am-3) was reduced by 28% compared with 50mM PBS (220±4Am-3), but it was still higher than that of the mixed culture (147±19Am-3), and strains PCA and GS-15 did not produce any current. Electrochemical tests showed that the improved performance of SD-1 was due to its lower charge transfer resistance and more negative potentials produced at higher current densities. These results show that the electrochemical activity of SD-1 was significantly different than other Geobacter strains and mixed cultures in terms of its salt tolerance.

G eobacter sp. SD-1 with enhanced electrochemical activity in high-salt concentration solutions

KAUST Repository

Sun, Dan

2014-07-16

© 2014 Society for Applied Microbiology and John Wiley & Sons Ltd. Summary: An isolate, designated strain SD-1, was obtained from a biofilm dominated by Geobacter sulfurreducens in a microbial fuel cell. The electrochemical activity of strain SD-1 was compared with type strains, G.sulfurreducensPCA and Geobacter metallireducensGS-15, and a mixed culture in microbial electrolysis cells. SD-1 produced a maximum current density of 290±29Am-3 in a high-concentration phosphate buffer solution (PBS-H, 200mM). This current density was significantly higher than that produced by the mixed culture (189±44Am-3) or the type strains (<70Am-3). In a highly saline water (SW; 50mM PBS and 650mM NaCl), current by SD-1 (158±4Am-3) was reduced by 28% compared with 50mM PBS (220±4Am-3), but it was still higher than that of the mixed culture (147±19Am-3), and strains PCA and GS-15 did not produce any current. Electrochemical tests showed that the improved performance of SD-1 was due to its lower charge transfer resistance and more negative potentials produced at higher current densities. These results show that the electrochemical activity of SD-1 was significantly different than other Geobacter strains and mixed cultures in terms of its salt tolerance.

Review: Water recovery from brines and salt-saturated solutions: operability and thermodynamic efficiency considerations for desalination technologies.

Science.gov (United States)

Vane, Leland M

2017-03-08

When water is recovered from a saline source, a brine concentrate stream is produced. Management of the brine stream can be problematic, particularly in inland regions. An alternative to brine disposal is recovery of water and possibly salts from the concentrate. This review provides an overview of desalination technologies and discusses the thermodynamic efficiencies and operational issues associated with the various technologies particularly with regard to high salinity streams. Due to the high osmotic pressures of the brine concentrates, reverse osmosis, the most common desalination technology, is impractical. Mechanical vapor compression which, like reverse osmosis, utilizes mechanical work to operate, is reported to have the highest thermodynamic efficiency of the desalination technologies for treatment of salt-saturated brines. Thermally-driven processes, such as flash evaporation and distillation, are technically able to process saturated salt solutions, but suffer from low thermodynamic efficiencies. This inefficiency could be offset if an inexpensive source of waste or renewable heat could be used. Overarching issues posed by high salinity solutions include corrosion and the formation of scales/precipitates. These issues limit the materials, conditions, and unit operation designs that can be used.

Process for the recovery of alkali metal salts from aqueous solutions thereof

International Nuclear Information System (INIS)

Vitner, J.

1984-01-01

In an integrated process for the recovery of alkakli metal phenates and carboxylates from aqueous solutions thereof, the aqueous solution is spray dried and the drying gas stream is contacted with an aqueous alkali metal salt solution which dissolves the particles of the alkali metal salt that were entrained in the drying gas stream. The salt-free inert gas stream is then dried, heated, and returned to the spray dryer

The influence of plutonium concentration and solution flow rate on the effective capacity of macroporous anion exchange resin

International Nuclear Information System (INIS)

Marsh, S.F.; Gallegos, T.D.

1987-07-01

The principal aqueous process used to recover and purify plutonium at the Los Alamos Plutonium Facility is anion exchange in nitric acid. Previous studies with gel-type anion exchange resin have shown an inverse relationship between plutonium concentration in the feed solution and the optimum flow rate for this process. Because gel-type resin has been replaced with macroporous resin at Los Alamos, the relationship between plutonium concentration and solution flow rate was reexamined with the selected Lewatit MP-500-FK resin using solutions of plutonium in nitric acid and in nitric acid with high levels of added nitrate salts. Our results with this resin differ significantly from previous data obtained with gel-type resin. Flow-rate variation from 10 to 80 liters per hour had essentially no effect on the measured quantities of plutonium sorbed by the macroporous resin. However, the effect of plutonium concentration in the feed solutions was pronounced, as feed solutions that contained the highest concentrations of plutonium also produced the highest resin loadings. The most notable effect of high concentrations of dissolved nitrate salts in these solutions was an increased resin capacity for plutonium at low flow rates. 16 refs., 7 figs., 2 tabs

Composite Properties of Polyimide Resins Made From "Salt-Like" Solution Precursors

Science.gov (United States)

Cano, Roberto J.; Weiser, Erik S.; SaintClair, Terry L.; Echigo, Yoshiaki; Kaneshiro, Hisayasu

1997-01-01

Recent work in high temperature materials at NASA Langley Research Center (LaRC (trademark)) have led to the development of new polyimide resin systems with very attractive properties. The majority of the work done with these resin systems has concentrated on determining engineering mechanical properties of composites prepared from a poly(amide acid) precursor. Three NASA Langley-developed polyimide matrix resins, LaRC (trademark) -IA, LaRC (trademark) -IAX, and LaRC (trademark) -8515, were produced via a salt-like process developed by Unitika Ltd. The 'salt-like' solutions (sixty-five percent solids in NMP) were prepregged onto Hexcel IM7 carbon fiber using the NASA LaRC Multipurpose Tape Machine. Process parameters were determined and composite panels fabricated. Mechanical properties are presented for these three intermediate modulus carbon fiber/polyimide matrix composites and compared to existing data on the same polyimide resin systems and IM7 carbon fiber manufactured via poly(amide acid) solutions (thirty-five percent solids in NMP). This work studies the effects of varying the synthetic route on the processing and mechanical properties of polyimide composites.

Assessment of iodine concentration in dietary salt at household level in Morocco.

Science.gov (United States)

Zahidi, Ahmed; Zahidi, Meriem; Taoufik, Jamal

2016-05-20

Following WHO recommendations, Morocco adopted in 1995 the universal salt iodization (USI) as a strategy to prevent and control iodine deficiency disorders. In 2009, the standard salt iodine concentration was adjusted to 15-40 mg/kg. The success of USI for the control of iodine deficiency disorders requires an evaluation of iodine concentration in salt prior to assessing the iodine nutritional status of a population. In our study we refer to the anterior studies that were made in Morocco in 1993 and 1998. 178 salt samples from households were tested for iodine using spot-testing kits. The iodometric titration method was used to analyze accurately the concentration of iodine in the 178 household salt samples. An empiric polling method was adopted, using a non-probability sampling method; across the different twelve regions in the country. The median and interquartile range iodine concentration in salt was 2.9 mg/kg (IQR: 2.4-3.7). The results show that only 25 % of households use iodized salt. The recommended iodine concentration in salt of 15-40 mg/kg was met only in 4.5 % of salt samples. The bulk salt is used by 8 % of households. All samples of this bulk salt were found in rural areas. According to nonparametric appropriate tests used, there is no significant difference in iodine concentrations between regions, between urban and rural areas and between packaged and bulk salt. Two decades since introducing legislation on Universal Salt Iodization, our survey shows that generalization of iodized salt is far from being reached. In 2015, only a quarter of Moroccan households use the iodized salt and only 4.5 % of salt is in conformity with regulations. The use of bulk salt by households in rural areas constitutes a major obstacle to the success of USI. The National Iodine Deficiency Disorders Control Program can only be achieved if an internal follow-up and a control of external quality of program is put in place.

Investigation into sorption of uranium fron its high-concentrated nitric acid solutions on resin AMP

International Nuclear Information System (INIS)

Savel'eva, V.I.; Sudarikov, B.N.; Kireeva, G.N.; Ryzhkova, V.N.; Kandaryuk, V.V.

1976-01-01

Sorption of uranium has been studied on strongly basic anion-exchange resin from nitric acid solutions with concentration in metal 10-150 g/l in presence of sodium, calcium, and aluminium nitrates. Sorption of uranium from solutions has been performed by the static method with the aid of contacting the initial solution with airdry resin for 4 hours, resin to solution ratio being 1:12.5. It has been established that sorption of uranium increases with a rise in concentration of salting out agents in the following order: Al(NO 3 ) 3 > Ca(NO 3 ) 2 > Na(NO 3 ). It has been shown spectrophotometricatly that in solutions of nitrates and HNO 3 with a concentration 3 exceeds 6 mol/l

Green Chemicals from d-glucose : Systematic Studies on Catalytic Effects of Inorganic Salts on the Chemo-Selectivity and Yield in Aqueous Solutions

NARCIS (Netherlands)

Rasrendra, C. B.; Makertihartha, I. G. B. N.; Adisasmito, S.; Heeres, H. J.

The use of inorganic salts as catalysts for the reactions of d-glucose in aqueous solutions in a batch reactor is reported. The type of salt and effect of reaction time were examined in detail at a fixed salt (5 mM) and d-glucose concentration (0.1 M) and at a temperature of 140 A degrees C. Al(III)

Br2 production from the heterogeneous reaction of gas-phase OH with aqueous salt solutions: Impacts of acidity, halide concentration, and organic surfactants.

Science.gov (United States)

Frinak, Elizabeth K; Abbatt, Jonathan P D

2006-09-07

This study reports the first laboratory measurement of gas-phase Br2 production from the reaction between gas-phase hydroxyl radicals and aqueous salt solutions. Experiments were conducted at 269 K in a rotating wetted-wall flow tube coupled to a chemical-ionization mass spectrometer for analysis of gas-phase components. From both pure NaBr solutions and mixed NaCl/NaBr solutions, the amount of Br2 released was found to increase with increasing acidity, whereas it was found to vary little with increasing concentration of bromide ions in the sample. For mixed NaCl/NaBr solutions, Br2 was formed preferentially over Cl2 unless the Br- levels in the solution were significantly depleted by OH oxidation, at which point Cl2 formation was observed. Presence of a surfactant in solution, sodium dodecyl sulfate, significantly suppressed the formation of Br2; this is the first indication that an organic surfactant can affect the rate of interfacial mass transfer of OH to an aqueous surface. The OH-mediated oxidation of bromide may serve as a source of active bromine in the troposphere and contribute to the subsequent destruction of ozone that proceeds in marine-influenced regions of the troposphere.

Simulating Osmotic Equilibria: A New Tool for Calculating Activity Coefficients in Concentrated Aqueous Salt Solutions.

Science.gov (United States)

Bley, Michael; Duvail, Magali; Guilbaud, Philippe; Dufrêche, Jean-François

2017-10-19

Herein, a new theoretical method is presented for predicting osmotic equilibria and activities, where a bulk liquid and its corresponding vapor phase are simulated by means of molecular dynamics using explicit polarization. Calculated time-averaged number density profiles provide the amount of evaporated molecules present in the vapor phase and consequently the vapor-phase density. The activity of the solvent and the corresponding osmotic coefficient are determined by the vapor density at different solute concentrations with respect to the reference vapor density of the pure solvent. With the extended Debye-Hückel equation for the activity coefficient along with the corresponding Gibbs-Duhem relation, the activity coefficients of the solutes are calculated by fitting the osmotic coefficients. A simple model based on the combination of Poisson processes and Maxwell-Boltzmann velocity distributions is introduced to interpret statistical phenomena observed during the simulations, which are related to evaporation and recondensation. This method is applied to aqueous dysprosium nitrate [Dy(NO 3 ) 3 ] solutions at different concentrations. The obtained densities of the liquid bulk and the osmotic and activity coefficients are in good agreement with the experimental results for concentrated and saturated solutions. Density profiles of the liquid-vapor interface at different concentrations provide detailed insight into the spatial distributions of all compounds.

Preparation of porous monolayer film by immersing the stearic acid Langmuir-Blodgett monolayer on mica in salt solution

Energy Technology Data Exchange (ETDEWEB)

Wang, S. [Institute of Near-Field Optics and Nano Technology, School of Physics and Optoelectronic Technology, Dalian University of Technology, Street No. 2 Linggong Road, Dalian 116024 (China); Li, Y.L.; Zhao, H.L.; Liang, H. [Institute of Photo-Biophysics, School of Physics and Electronic, Henan University, Jinming, Kaifeng 475004, Henan (China); Liu, B., E-mail: boliu@henu.edu.cn [Institute of Photo-Biophysics, School of Physics and Electronic, Henan University, Jinming, Kaifeng 475004, Henan (China); Pan, S., E-mail: span@dlut.edu.cn [Institute of Near-Field Optics and Nano Technology, School of Physics and Optoelectronic Technology, Dalian University of Technology, Street No. 2 Linggong Road, Dalian 116024 (China)

2012-11-15

Highlights: Black-Right-Pointing-Pointer Porous film has been prepared by immersing the stearic acid Langmuir-Blodgett monolayer on mica in salt solution. Black-Right-Pointing-Pointer The mechanism relies on the electrostatic screening effect of the cations in salt solution. Black-Right-Pointing-Pointer The factors influencing the size and area of the pores were investigated. - Abstract: Porous materials have drawn attention from scientists in many fields such as life sciences, catalysis and photonics since they can be used to induce some materials growth as expected. Especially, porous Langmuir-Blodgett (LB) film is an ideal material with controlled thickness and flat surface. In this paper, stearic acid (SA), which has been extensively explored in LB film technique, is chosen as the template material with known parameters to prepare the LB film, and then the porous SA monolayer film is obtained by means of etching in salt solution. The main etching mechanism is suggested that the cations in the solution block the electrostatic interaction between the polar carboxyl group of SA and the electronegative mica surface. The influencing factors (such as concentration of salt solution, valence of cation and surface pressure) of the porous SA film are systematically studied in this work. The novel method proposed in this paper makes it convenient to prepare porous monolayer film for designed material growth or cell culture.

Effect of temperature on solvation behaviour of diclofenac sodium salt in aqueous glycine and L-proline solutions

International Nuclear Information System (INIS)

Ryshetti, Suresh; Gardas, Ramesh L; Tangeda, Savitha Jyostna

2015-01-01

Highlights: • Solvation behaviour of diclofenac drug studied in aqueous solutions. • Density and speed of sound of drug in aq. glycine and L-proline are measured. • Hydrophobic nature of diclofenac sodium salt is studied. • Effect of temperature on solvation of diclofenac sodium salt is analysed. - Abstract: Apparent molar volume (V 2,ϕ ) and apparent molar isentropic compressibility (K s,2,ϕ ) of diclofenac sodium salt (DSS) drug within the concentration range of (0.001 to 0.008) mol · kg −1 in (0.01, 0.03 and 0.05) mol · kg −1 aqueous glycine and L-proline solutions are computed from the experimental density (ρ) and speed of sound (u) values at T = (293.15 to 313.15) K and atmospheric pressure. Derived parameters such as partial molar properties, transfer partial molar properties, hydration numbers and Hepler’s constant are computed from the data of V 2,ϕ and K s,2,ϕ . These parameters have been used to understand the effect of temperature on interactions between DSS drug and aqueous glycine/L-proline solution. Furthermore, the structure making and breaking ability of DSS drug in probed solutions are analysed at experimental conditions

Thermosolutal convection in saturated porous enclosure with concentrated energy and solute sources

Energy Technology Data Exchange (ETDEWEB)

Liu, Di; Zhao, Fu-Yun; Tang, Guang-Fa [College of Civil Engineering, Hunan University, Changsha (China)

2008-01-15

Double diffusive natural convection within a vertical porous enclosure with localized heating and salting from one side is numerically studied by the finite element based finite volume method. In the formulation of the problem, use is made of the Darcy model, which allows the slip boundary condition on a solid wall to be satisfied. Comparisons with benchmark solutions for natural convection in fluid saturated porous enclosures are first presented to validate the code. Following that, an extensive series of numerical simulations is conducted in the range of -55 {<=} N {<=} + 55 and 0.125 {<=} L {<=} 0.875, where N and L are the buoyancy ratio and the element location, respectively. Streamlines, heatlines, masslines, isotherms and iso-concentrations in the system are produced to illustrate the flow structure transition from solutal dominated opposing to thermal dominated and solutal dominated aiding flows, respectively. The computed average Nusselt and Sherwood numbers provide guidance for locating the heating and salting element. (author)

Thermosolutal convection in saturated porous enclosure with concentrated energy and solute sources

Energy Technology Data Exchange (ETDEWEB)

Liu Di [College of Civil Engineering, Hunan University, Changsha (China)], E-mail: liudi66@163.com; Zhao Fuyun [College of Civil Engineering, Hunan University, Changsha (China)], E-mail: zfycfdnet@163.com; Tang Guangfa [College of Civil Engineering, Hunan University, Changsha (China)], E-mail: gftangcfd@163.com

2008-01-15

Double diffusive natural convection within a vertical porous enclosure with localized heating and salting from one side is numerically studied by the finite element based finite volume method. In the formulation of the problem, use is made of the Darcy model, which allows the slip boundary condition on a solid wall to be satisfied. Comparisons with benchmark solutions for natural convection in fluid saturated porous enclosures are first presented to validate the code. Following that, an extensive series of numerical simulations is conducted in the range of -55 {<=} N {<=} + 55 and 0.125 {<=} L {<=} 0.875, where N and L are the buoyancy ratio and the element location, respectively. Streamlines, heatlines, masslines, isotherms and iso-concentrations in the system are produced to illustrate the flow structure transition from solutal dominated opposing to thermal dominated and solutal dominated aiding flows, respectively. The computed average Nusselt and Sherwood numbers provide guidance for locating the heating and salting element.

Concentration of iodine in edible salt in district mansehra, pakistan

International Nuclear Information System (INIS)

Gul, R.; Mustafa, A.; Khalil, K.U.R.; Faisal, M.S.

2017-01-01

To determine the status of iodization of edible salt of different brands available in the market and used at homes in district Mansehra, Pakistan. Methodology: This cross-sectional study was conducted in District Mansehra between December 2016 to March 2017. Samples were selected from 8 union councils through non probability convenient sampling technique. Salt analyzing kits were used to determine amount of iodine in each sample. Results: The mean iodine concentration of salt available in the market was 23.6+-10.461 ppm; while that of the household salt was 22.85+-10.696 ppm. Overall, 82% of the samples had iodine concentration within ecommended level i.e. 15-30ppm. No iodine was found in 13.2% of the samples and 4.8% of the samples had below recommended level. Conclusion: The percentage of adequately iodized salt in the market (83.9%) was better than that of households (81.5%). Overall samples of edible salt showed adequate amount of iodine. (author)

Thermodynamic study of aqueous solutions of polyelectrolytes of low and medium charge density without added salt by direct measurement of osmotic pressure

Energy Technology Data Exchange (ETDEWEB)

Nagy, Miklos, E-mail: miklosnagy@chem.elte.h [Institute of Chemistry, Department of Physical Chemistry, Laboratory for Colloid and Supermolecular Structures, L. Eoetvoes University, P.O. Box 32 H-1518 Budapest 112 (Hungary)

2010-03-15

A special block osmometer has been constructed and applied to a systematic study of poly (vinyl alcohol and vinyl sulphate ester) (PVS) sodium salts in dilute and moderately concentrated salt free aqueous solutions. In order to avoid surely ionic contamination all parts of the equipment that can contact with the polyelectrolyte solutions were made of different kinds of plastics and glass. The pressure range spans from (50 to 1.3 . 10{sup 5}) Pa. The measuring system was found to be appropriate for determination of the molar mass of water soluble polymers, too. Above a certain analytical density of dissociable groups (ADDG) an ion size dependent transition was observed on the reduced osmotic pressure vs. concentration curves. The analysis of the osmotic pressure data has clearly revealed that the dependence of the degree of dissociation on ADDG calculated at zero polyelectrolyte concentration contradicts to 'ion condensation' theory. With increasing polyelectrolyte concentration the degree of dissociation decreased rather steeply but at very low concentrations sharp maximums appeared due either to the change in conformation of these charged macromolecules, or formation of dynamic clusters induced by salting out of neutral parts of the macromolecules by the ionized groups. The applicability of the scaling concept as well as the many possible ways of characterization of non-ideality of polyelectrolyte solutions will be discussed in detail.

On the hydrophilicity of polyzwitterion poly (N,N-dimethyl-N-(3-(methacrylamido)propyl)ammoniopropane sulfonate) in water, deuterated water, and aqueous salt solutions.

Science.gov (United States)

Hildebrand, Viet; Laschewsky, André; Zehm, Daniel

2014-01-01

A series of zwitterionic model polymers with defined molar masses up to 150,000 Da and defined end groups are prepared from sulfobetaine monomer N,N-dimethyl-N-(3-(methacrylamido)propyl)ammoniopropanesulfonate (SPP). Polymers are synthesized by reversible addition-fragmentation chain transfer polymerization (RAFT) using a functional chain transfer agent labeled with a fluorescent probe. Their upper critical solution temperature-type coil-to-globule phase transition in water, deuterated water, and various salt solutions is studied by turbidimetry. Cloud points increase with polyzwitterion concentration and molar mass, being considerably higher in D2O than in H2O. Moreover, cloud points are strongly affected by the amount and nature of added salts. Typically, they increase with increasing salt concentration up to a maximum value, whereas further addition of salt lowers the cloud points again, mostly down to below freezing point. The different salting-in and salting-out effects of the studied anions can be correlated with the Hofmeister series. In physiological sodium chloride solution and in phosphate buffered saline (PBS), the cloud point is suppressed even for high molar mass samples. Accordingly, SPP-polymers behave strongly hydrophilic under most conditions encountered in biomedical applications. However, the direct transfer of results from model studies in D2O, using, e.g. (1)H NMR or neutron scattering techniques, to 'normal' systems in H2O is not obvious.

The effect of divalent salt in chondroitin sulfate solutions

Energy Technology Data Exchange (ETDEWEB)

Aranghel, D., E-mail: daranghe@nipne.ro [Horia Hulubei National Institute of Physics and Nuclear Engineering, Reactorului 30, RO-077125, POB-MG6, Magurele-Bucharest, Romania, daranghe@nipne.ro (Romania); Extreme Light Intrastructure Nuclear Physics (ELI-NP), Reactorului 30,RO-077125, POB-MG6, Magurele-Bucharest (Romania); Badita, C. R. [Horia Hulubei National Institute of Physics and Nuclear Engineering, Reactorului 30, RO-077125, POB-MG6, Magurele-Bucharest, Romania, daranghe@nipne.ro (Romania); University of Bucharest, Faculty of Physics, Atomiştilor 405, CP MG - 11, RO – 077125, Bucharest-Magurele (Romania); Radulescu, A. [Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Science, 85747 Garching (Germany); Moldovan, L.; Craciunescu, O. [National Institute R& D for Biological Sciences, Splaiul Independenţei 296, sector 6, cod 060031, C.P. 17-16, Bucharest (Romania); Balasoiu, M. [Horia Hulubei National Institute of Physics and Nuclear Engineering, Reactorului 30, RO-077125, POB-MG6, Magurele-Bucharest, Romania, daranghe@nipne.ro (Romania); Joint Institute for Nuclear Research, 141980 Dubna, Moscow region (Russian Federation)

2016-03-25

Chondroitin-4 sulfate (CS4) is the main glycosaminoglycan extracted from bovine trachea. CS4 play an important role in osteoarthritis treatment, anticoagulant activity, reduces the degradation of cartilage matrix components, reduces necrosis and apoptosis of chondrocytes and reduces the activity of collagenase. Chondroitin sulfate is also responsible for proteoglycans degradation. Chondroitin sulfate can bind calcium ions with different affinities, depending on their sulfation position. The purpose of this study was to determine the structural properties and the influence of Ca{sup 2+} cations. We carried out measurements on CS4 solutions and mixtures of liquid CS4 with Ca{sup 2+} by Small-Angle Neutron Scattering (SANS). CS4 have a mass fractal behavior and the addition of a salt (CaCl{sub 2}) in CS4 solutions generates the appearance of a correlation peak due to local ordering between adjacent chains with inter-chain distances between 483 Å and 233 Å for a calcium concentration of 0.01% w/w.

The effect of divalent salt in chondroitin sulfate solutions

Science.gov (United States)

Aranghel, D.; Badita, C. R.; Radulescu, A.; Moldovan, L.; Craciunescu, O.; Balasoiu, M.

2016-03-01

Chondroitin-4 sulfate (CS4) is the main glycosaminoglycan extracted from bovine trachea. CS4 play an important role in osteoarthritis treatment, anticoagulant activity, reduces the degradation of cartilage matrix components, reduces necrosis and apoptosis of chondrocytes and reduces the activity of collagenase. Chondroitin sulfate is also responsible for proteoglycans degradation. Chondroitin sulfate can bind calcium ions with different affinities, depending on their sulfation position. The purpose of this study was to determine the structural properties and the influence of Ca2+ cations. We carried out measurements on CS4 solutions and mixtures of liquid CS4 with Ca2+ by Small-Angle Neutron Scattering (SANS). CS4 have a mass fractal behavior and the addition of a salt (CaCl2) in CS4 solutions generates the appearance of a correlation peak due to local ordering between adjacent chains with inter-chain distances between 483 Å and 233 Å for a calcium concentration of 0.01% w/w.

The effect of divalent salt in chondroitin sulfate solutions

International Nuclear Information System (INIS)

Aranghel, D.; Badita, C. R.; Radulescu, A.; Moldovan, L.; Craciunescu, O.; Balasoiu, M.

2016-01-01

Chondroitin-4 sulfate (CS4) is the main glycosaminoglycan extracted from bovine trachea. CS4 play an important role in osteoarthritis treatment, anticoagulant activity, reduces the degradation of cartilage matrix components, reduces necrosis and apoptosis of chondrocytes and reduces the activity of collagenase. Chondroitin sulfate is also responsible for proteoglycans degradation. Chondroitin sulfate can bind calcium ions with different affinities, depending on their sulfation position. The purpose of this study was to determine the structural properties and the influence of Ca"2"+ cations. We carried out measurements on CS4 solutions and mixtures of liquid CS4 with Ca"2"+ by Small-Angle Neutron Scattering (SANS). CS4 have a mass fractal behavior and the addition of a salt (CaCl_2) in CS4 solutions generates the appearance of a correlation peak due to local ordering between adjacent chains with inter-chain distances between 483 Å and 233 Å for a calcium concentration of 0.01% w/w.

Influence of solvent and salt concentration on the alignment properties of acrylamide copolymer gels for the measurement of RDC.

Science.gov (United States)

Trigo-Mouriño, Pablo; Navarro-Vázquez, Armando; Sánchez-Pedregal, Víctor M

2012-12-01

The dependence of molecular alignment with solvent nature and salt concentration has been investigated for mechanically stretched polyacrylamide copolymer gels. Residual dipolar couplings (RDCs) were recorded for D(2)O, DMSO-d(6), and DMSO-d(6)/D(2)O solutions containing different proportions of the solvents and different sodium chloride concentrations. Alignment tensors were determined by fitting the experimental RDCs to the DFT-computed structure of N-methylcodeinium ion. Analysis of the tensors shows that the degree of alignment decreases with the proportion of DMSO-d(6) as well as with the concentration of sodium chloride, most likely due to enhanced ion-pair aggregation. Furthermore, rotation of the alignment tensor is observed when increasing the salt concentration. Copyright © 2012 John Wiley & Sons, Ltd.

Optical absorption of dilute solutions of metals in molten salts

Energy Technology Data Exchange (ETDEWEB)

Senatore, G.; Parrinello, M.; Tosi, M.P. (Trieste Univ. (Italy). Ist. di Fisica Teorica; Gruppo Nazionale di Struttura dell material del CNR, Trieste (Italy); International Centre for Theoretical Physics, Trieste (Italy))

1978-12-23

The theory of liquid structure for fluids of charged hard spheres is applied to an evaluation of the F-centre model for valence electrons in metal-molten salt solutions at high dilution. Minimization of the free energy yields the groundstate radius of the elctron bubble and hence the optical excitation energy in a Franck-Condon transition, the shift and broadening of the transition due to fluctuations in the bubble radius, the volume of mixing, and the activity of the salt in the solution.

Determination of the osmotic second virial coefficient and the demerization of beta-lactoglobulin in aqueous solutions with added salt at the isoelectric point

NARCIS (Netherlands)

Schaink, H.M.; Smit, J.A.M.

2000-01-01

Aqueous solutions of β-lactoglobulin (at the isoelectric point pH=5.18) have been studied by membrane osmometry. The osmotic second virial coefficient as well as the monomer–dimer equilibrium of β-lactoglobulin have been found to depend significantly on the salt concentration. At low salt

Adsorption of Sr(II) on clay minerals: effects of salt concentration, loading and pH

International Nuclear Information System (INIS)

Rafferty, P.; Shiao, S.Y.; Binz, C.M.; Meyer, R.E.

1981-01-01

The adsorption of Sr(II) on a number of clay minerals has been investigated by means of a batch technique in solutions of sodium salts. Generally the results can be approximated by ideal ion exchange equations. Distribution coefficients at trace loading follow the linear relation log D = s log [Na(I)sub(aq)] + b where b is a constant and s had values of from about - 1.5 to - 2.0, which are fairly close to the ideal valve of - 2. Adsorption isotherms at constant pH and salt concentration are linear in the low loading region. Distribution coefficients for montmorillonite are almost independent of pH in the intermediate pH region 5 to 7 but for illite and kaolinite, increases in the distribution coefficient with pH are observed. Comparison of these results with literature values, insofar as it is possible, shows that distribution coefficients are usually within a factor of two or three for the same mineral with similar capacities under the same conditions even if techniques of preparation and measurement are different, but values may vary considerably more if the capacities of the different mineral samples are greatly different. Values of the distribution coefficient at very high salt concentration are very low, considerably less than unity at 4 M NaCl. Thus migration rates of Sr(II), relative to water flow, through geologic formations whose adsorption behavior is dominated by these clay minerals are likely to be high at high salt concentrations. (author)

Investigation of complexing in solutions of salt mixture In(NO/sub 3/)/sub 3/-NaVO/sub 3/

Energy Technology Data Exchange (ETDEWEB)

Nakhodnova, A N; Listratenko, I V

1987-05-01

Spectrophotometry, conductometry and pH-metry are used to investigate properties and composition of the solid phases of isomolar series of In(NO/sub 3/)/sub 3/-NaVO/sub 3/ salt mixture solutions and series of solutions having constant concentration of one of the components and varied of the other. Results of investigation are presented. It is stated that in the investigated solution series in weakly acid media HPA with the ratios (In/sup 3+/):(V/sup 5+/) being equal to 11:1, 6:1, and 1:9, are formed. Composition of the complexes is mainly defined by the ratio of the components in In(NO/sub 3/)/sub 3/ and NaVO/sub 3/ salt mixture solutions and the medium acidity. Compounds of Na/sub 2/OxIn/sub 2/O/sub 3/x2.5V/sub 2/O/sub 5/x8.5H/sub 2/O and Cs/sub 2/OxIn/sub 2/O/sub 3/x6V/sub 2/O/sub 5/x6.5H/sub 2/O empirical formulae are separated. Results of IR spectroscopy, derivatography and X-ray phase analysis of the corresponding salts are presented.

Effect of ammonium-salt solutions on the surface properties of carbon fibers in electrochemical anodic oxidation

Energy Technology Data Exchange (ETDEWEB)

Qian Xin, E-mail: qx3023@nimte.ac.cn [National Engineering Laboratory of Carbon Fiber Preparation Technology, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Wang Xuefei; Ouyang Qin; Chen Yousi; Yan Qing [National Engineering Laboratory of Carbon Fiber Preparation Technology, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China)

2012-10-15

Highlights: Black-Right-Pointing-Pointer Longitudinal grooves on the fiber surface became more well-defined and much deeper after surface treatment. Black-Right-Pointing-Pointer The concentration of oxygen and nitrogen on the fiber surface increased after surface treatment. Black-Right-Pointing-Pointer The intensity of oxidative reaction varied with the change of ammonium-salt solutions. Black-Right-Pointing-Pointer The higher the concentration of OH{sup -} ions in the electrolytes, the violent the oxidative reaction happened. - Abstract: The surfaces of polyacrylonitrile-based carbon fibers were treated by an electrochemical anodic method. Three different kinds of ammonium-salt solutions namely NH{sub 4}HCO{sub 3}, (NH{sub 4}){sub 2}CO{sub 3} and (NH{sub 4}){sub 3}PO{sub 4} were respectively chosen as the electrolytes. The effect of these electrolytes on the surface structure was studied by scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS). The results showed that longitudinal grooves on the fiber surface became more well-defined and much deeper after surface treatment, and the root mean square roughness (RMS) of carbon fiber surface increased from 4.6 nm for untreated fibers to 13.5 nm for treated fibers in (NH{sub 4}){sub 3}PO{sub 4} electrolytes. The concentration of oxygen and nitrogen atomic on the fiber surface increased after surface treatment. The tensile strength of oxidized fibers had an obvious decrease, whereas the interlaminar shear strength (ILSS) value of corresponding carbon fiber reinforced polymers (CFRPs) increased in a large extent. The intensity of oxidative reaction varied with the change of ammonium-salt solutions and electrochemical oxidation in (NH{sub 4}){sub 3}PO{sub 4} electrolyte was of the most violence. The corresponding mechanism was also discussed and the result showed that the higher the concentration of OH{sup -} ions in the electrolytes, the violent the oxidative

COBALT SALTS PRODUCTION BY USING SOLVENT EXTRACTION

Directory of Open Access Journals (Sweden)

Liudmila V. Dyakova

2010-06-01

Full Text Available The paper deals with the extracting cobalt salts by using mixtures on the basis of tertiary amine from multicomponent solutions from the process of hydrochloride leaching of cobalt concentrate. The optimal composition for the extraction mixture, the relationship between the cobalt distribution coefficients and modifier’s nature and concentration, and the saltingout agent type have been determined. A hydrochloride extraction technology of cobalt concentrate yielding a purified concentrated cobalt solution for the production of pure cobalt salts has been developed and introduced at Severonikel combine.

Centrifugal separation for miscible solutions: Fundamentals and applications to separation of molten salt nuclear material

International Nuclear Information System (INIS)

Li Ning; Camassa, Roberto; Ecke, Robert E.; Venneri, Francesco

1995-01-01

We report on the physical separation of dilute solutions using centrifugal techniques. We use numerical simulations of the diffusion and sedimentation dynamics of centrifugation to model the approach to an equilibrium concentration profile. We verify experimentally the equilibrium profiles for aqueous solutions of different salts under rotation at 25000 rpm corresponding to centrifugal accelerations of about 57,000 g and 75,000 g in two different commercial centrifuges. These measurements provide ratios of sedimentation and diffusion coefficients. We show experimental results for the dynamics of separation that confirm the predictions of the theoretical model. We also measure the mass diffusion coefficient for several solutions. Although the relaxation to equilibrium is long, we have determined a method for efficiently extracting enriched components from a ternary mixture based on fast dynamics at early times. These dynamics are modeled in numerical simulations with realistic fluid parameters. Based on these studies we show that a multistage centrifugal separation process could provide efficient physical separation of actinides and fission products from a molten-salt solution in proposed transmutation/energy-production systems. We consider technical issues in the design of such a separation system

Centrifugal separation for miscible solutions: Fundamentals and applications to separation of molten salt nuclear material

International Nuclear Information System (INIS)

Ning Li; Camassa, R.; Ecke, R.E.

1995-01-01

The authors report on the physical separation of dilute solutions using centrifugal techniques. They use numerical simulations of the diffusion and sedimentation dynamics of centrifugation to model the approach to an equilibrium concentration profile. They verify experimentally the equilibrium profiles for aqueous solutions of different salts under rotation at 25000 rpm corresponding to centrifugal accelerations of about 57,000 g and 75,000 g in two different commercial centrifuges. These measurements provide ratios of sedimentation and diffusion coefficients. The authors show experimental results for the dynamics of separation that confirm the predictions of the theoretical model. They also measure the mass diffusion coefficient for several solutions. Although the relaxation to equilibrium is long, they have determined a method for efficiently extracting enriched components from a ternary mixture based on fast dynamics at early times. These dynamics are modeled in numerical simulations with realistic fluid parameters. Based on these studies the authors show that a multistage centrifugal separation process could provide efficient physical separation of actinides and fission products from a molten-salt solution in proposed transmutation/energy-production systems. The authors consider technical issues in the design of such a separation system

Centrifugal separation for miscible solutions: Fundamentals and applications to separation of molten salt nuclear material

Energy Technology Data Exchange (ETDEWEB)

Ning Li; Camassa, R.; Ecke, R.E. [Los Alamos National Laboratory, NM (United States)] [and others

1995-10-01

The authors report on the physical separation of dilute solutions using centrifugal techniques. They use numerical simulations of the diffusion and sedimentation dynamics of centrifugation to model the approach to an equilibrium concentration profile. They verify experimentally the equilibrium profiles for aqueous solutions of different salts under rotation at 25000 rpm corresponding to centrifugal accelerations of about 57,000 g and 75,000 g in two different commercial centrifuges. These measurements provide ratios of sedimentation and diffusion coefficients. The authors show experimental results for the dynamics of separation that confirm the predictions of the theoretical model. They also measure the mass diffusion coefficient for several solutions. Although the relaxation to equilibrium is long, they have determined a method for efficiently extracting enriched components from a ternary mixture based on fast dynamics at early times. These dynamics are modeled in numerical simulations with realistic fluid parameters. Based on these studies the authors show that a multistage centrifugal separation process could provide efficient physical separation of actinides and fission products from a molten-salt solution in proposed transmutation/energy-production systems. The authors consider technical issues in the design of such a separation system.

Corrosion processes of alloyed steels in salt solutions

Energy Technology Data Exchange (ETDEWEB)

Kienzler, Bernhard [Karlsruher Institut fuer Technologie (KIT), Eggenstein-Leopoldshafen (Germany). Institut fuer Nukleare Entsorgung

2018-02-15

A summary is given of the corrosion experiments with alloyed Cr-Ni steels in salt solutions performed at Research Centre Karlsruhe (today KIT), Institute for Nuclear Waste Disposal (INE) in the period between 1980 and 2004. Alloyed steels show significantly lower general corrosion in comparison to carbon steels. However, especially in salt brines the protective Cr oxide layers on the surfaces of these steels are disturbed and localized corrosion takes place. Data on general corrosion rates, and findings of pitting, crevice and stress corrosion cracking are presented.

Neptunium sorption and co-precipitation of strontium in simulated DWPF salt solution

International Nuclear Information System (INIS)

McIntyre, P.F.; Orebaugh, E.G.; King, C.M.

1988-01-01

Batch experiments performed using crushed slag saltstone (∼40 mesh) removed >80% of 237 Np from simulated Defense Waste Processing Facility (DWPF) salt solution. The concentration of 237 Np (110 pCi/ml) used was 1000x greater than levels in actual DWPF solutions. Neptunium-239 was used as a tracer and was formed by neutron activation of uranyl nitrate. Results showed that small amounts of crushed saltstone (as little as 0.05 grams), removed >80% of neptunium from 15 ml of simulated DWPF solution after several hours equilibration. The neptunium is sorbed on insoluble carbonates formed in and on the saltstone matrix. Further testing showed that addition of 0.01 and 0.10 ml of 1 molar Ca +2 (ie. Ca (NO 3 ) 2 , CaCl 2 ) into 15 ml of simulated DWPF solution yielded a white carbonate precipitate which also removed >80% of the neptunium after 1 hour equilibration. Further experiments were performed to determine the effectiveness of this procedure to co-precipitate strontium

Diclofenac Salts, VIII. Effect of the Counterions on the Permeation through Porcine Membrane from Aqueous Saturated Solutions

Science.gov (United States)

Fini, Adamo; Bassini, Glenda; Monastero, Annamaria; Cavallari, Cristina

2012-01-01

The following bases: monoethylamine (EtA), diethylamine (DEtA), triethylamine (TEtA), monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), pyrrolidine (Py), piperidine (Pp), morpholine (M), piperazine (Pz) and their N-2-hydroxyethyl (HE) analogs were employed to prepare 14 diclofenac salts. The salts were re-crystallized from water in order to obtain forms that are stable in the presence of water. Vertical Franz-type cells with a diffusional surface area of 9.62 cm2 were used to study the permeation of these diclofenac salts from their saturated solutions through an internal pig ear membrane. The receptor compartments of the cells contained 100 mL of phosphate buffer (pH 7.4); a saturated solution (5 mL) of each salt was placed in the donor compartment, thermostated at 37 °C. Aliquots were withdrawn at predetermined time intervals over 8 h and then immediately analyzed by HPLC. Fluxes were determined by plotting the permeated amount, normalized for the membrane surface area versus time. Permeation coefficients were obtained dividing the flux values J by the concentration of the releasing phase—that is, water solubility of each salt. Experimental results show that fluxes could be measured when diclofenac salts with aliphatic amines are released from a saturated aqueous solution. Different chemical species (acid, anion, ion pairs) contribute to permeation of the anti-inflammatory agent even though ion-pairs could be hypothesized to operate to a greater extent. Permeation coefficients were found higher when the counterion contains a ring; while hydroxy groups alone do not appear to play an important role, the ring could sustain permeation, disrupting the organized domains of the membrane. PMID:24300300

Evaluation of the salt deposition on the canister surface of concrete cask. Part 2. Measurement test of the salt concentration in air and salt deposition in the field

International Nuclear Information System (INIS)

Wataru, Masumi

2012-01-01

Concerning the storage facility of spent nuclear fuel using the concrete cask, there is an issue of stress corrosion cracking(SCC). The cooling air goes up along the canister surface in the concrete cask. To evaluate the initiation of SCC or rusting, it is important to verify the estimation method of the sea salt deposition on the metal canister surface transported by cooling air including sea salt particles. To measure the deposition rate, field tests were performed in Choushi test center. In the field test, it was found that the amount of sea salt deposition was very low because the density of the atmospheric sea salt concentration was very low compared with the laboratory test. Using relation between laboratory data and filed data, it is possible to evaluate the salt deposition rate on the canister surface. We also measured atmospheric sea salt concentration in Choushi test center to make the environment condition clear and compared the measurement data with the calculation data to verify the evaluation model. We are developing the automatic measuring device for atmospheric sea salt concentration. To check its performance, we are measuring atmospheric sea salt concentration in Yokosuka Area of CRIEPI and it was confirmed that the device works for one month automatically and fulfills its specifications. (author)

SODIUM ALUMINOSILICATE FOULING AND CLEANING OF DECONTAMINATED SALT SOLUTION COALESCERS

International Nuclear Information System (INIS)

Poirier, M.; Thomas Peters, T.; Fernando Fondeur, F.; Samuel Fink, S.

2008-01-01

During initial non-radioactive operations at the Modular Caustic Side Solvent Extraction Unit (MCU), the pressure drop across the decontaminated salt solution coalescer reached ∼10 psi while processing ∼1250 gallons of salt solution, indicating possible fouling or plugging of the coalescer. An analysis of the feed solution and the 'plugged coalescer' concluded that the plugging was due to sodium aluminosilicate solids. MCU personnel requested Savannah River National Laboratory (SRNL) to investigate the formation of the sodium aluminosilicate solids (NAS) and the impact of the solids on the decontaminated salt solution coalescer. Researchers performed developmental testing of the cleaning protocols with a bench-scale coalescer container 1-inch long segments of a new coalescer element fouled using simulant solution. In addition, the authors obtained a 'plugged' Decontaminated Salt Solution coalescer from non-radioactive testing in the MCU and cleaned it according to the proposed cleaning procedure. Conclusions from this testing include the following: (1) Testing with the bench-scale coalescer showed an increase in pressure drop from solid particles, but the increase was not as large as observed at MCU. (2) Cleaning the bench-scale coalescer with nitric acid reduced the pressure drop and removed a large amount of solid particles (11 g of bayerite if all aluminum is present in that form or 23 g of sodium aluminosilicate if all silicon is present in that form). (3) Based on analysis of the cleaning solutions from bench-scale test, the 'dirt capacity' of a 40 inch coalescer for the NAS solids tested is calculated as 450-950 grams. (4) Cleaning the full-scale coalescer with nitric acid reduced the pressure drop and removed a large amount of solid particles (60 g of aluminum and 5 g of silicon). (5) Piping holdup in the full-scale coalescer system caused the pH to differ from the target value. Comparable hold-up in the facility could lead to less effective cleaning and

Domestic Material Content in Molten-Salt Concentrating Solar Power Plants

Energy Technology Data Exchange (ETDEWEB)

Turchi, Craig [National Renewable Energy Lab. (NREL), Golden, CO (United States); Kurup, Parthiv [National Renewable Energy Lab. (NREL), Golden, CO (United States); Akar, Sertac [National Renewable Energy Lab. (NREL), Golden, CO (United States); Flores, Francisco [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2015-08-26

This study lists material composition data for two concentrating solar power (CSP) plant designs: a molten-salt power tower and a hypothetical parabolic trough plant, both of which employ a molten salt for the heat transfer fluid (HTF) and thermal storage media. The two designs have equivalent generating and thermal energy storage capacities. The material content of the saltHTF trough plant was approximately 25% lower than a comparably sized conventional oil-HTF parabolic trough plant. The significant reduction in oil, salt, metal, and insulation mass by switching to a salt-HTF design is expected to reduce the capital cost and LCOE for the parabolic trough system.

Preliminary evaluation of solution-mining intrusion into a salt-dome repository

International Nuclear Information System (INIS)

1981-06-01

This report is the product of the work of an ONWI task force to evaluate inadvertant human intrusion into a salt dome repository by solution mining. It summarizes the work in the following areas: a general review of the levels of defense that could reduce both the likelihood and potential consequences of human intrusion into a salt dome repository; evaluation of a hypothetical intrusion scenario and its consequences; recommendation for further studies. The conclusions of this task force report can be summarized as follows: (1) it is not possible at present to establish with certainty that solution mining is credible as a human-intrusion event. The likelihood of such an intrusion will depend on the effectiveness of the preventive measures; (2) an example analysis based on the realistic approach is presented in this report; it concluded that the radiological consequences are strongly dependent upon the mode of radionuclide release from the waste form, time after emplacement, package design, impurities in the host salt, the amount of a repository intercepted, the solution mining cavity form, the length of time over which solution mining occurs, the proportion of contaminated salt source for human consumption compared to other sources, and the method of salt purification for culinary purposes; (3) worst case scenarios done by other studies suggest considerable potential for exposures to man while preliminary evaluations of more realistic cases suggest significantly reduced potential consequences. Mathematical model applications to process systems, guided by more advanced assumptions about human intrusion into geomedia, will shed more light on the potential for concerns and the degree to which mitigative measures will be required

High salt intake increases plasma trimethylamine N-oxide (TMAO) concentration and produces gut dysbiosis in rats.

Science.gov (United States)

Bielinska, Klaudia; Radkowski, Marek; Grochowska, Marta; Perlejewski, Karol; Huc, Tomasz; Jaworska, Kinga; Motooka, Daisuke; Nakamura, Shota; Ufnal, Marcin

2018-03-22

A high-salt diet is considered a cardiovascular risk factor; however, the mechanisms are not clear. Research suggests that gut bacteria-derived metabolites such as trimethylamine N-oxide (TMAO) are markers of cardiovascular diseases. We evaluated the effect of high salt intake on gut bacteria and their metabolites plasma level. Sprague Dawley rats ages 12-14 wk were maintained on either water (controls) or 0.9% or 2% sodium chloride (NaCl) water solution (isotonic and hypertonic groups, respectively) for 2 wk. Blood plasma, urine, and stool samples were analyzed for concentrations of trimethylamine (TMA; a TMAO precursor), TMAO, and indoxyl sulfate (indole metabolite). The gut-blood barrier permeability to TMA and TMA liver clearance were assessed at baseline and after TMA intracolonic challenge test. Gut bacterial flora was analyzed with a 16S ribosomal ribonucleic acid (rRNA) gene sequence analysis. The isotonic and hypertonic groups showed a significantly higher plasma TMAO and significantly lower 24-hr TMAO urine excretion than the controls. However, the TMA stool level was similar between the groups. There was no significant difference between the groups in gut-blood barrier permeability and TMA liver clearance. Plasma indoxyl concentration and 24-hr urine indoxyl excretion were similar between the groups. There was a significant difference between the groups in gut bacteria composition. High salt intake increases plasma TMAO concentration, which is associated with decreased TMAO urine excretion. Furthermore, high salt intake alters gut bacteria composition. These findings suggest that salt intake affects an interplay between gut bacteria and their host homeostasis. Copyright © 2018 Elsevier Inc. All rights reserved.

The effect of emulsifying salts on the turbidity of a diluted milk system with varying pH and protein concentration.

Science.gov (United States)

Culler, M D; Saricay, Y; Harte, F M

2017-06-01

Solutions of 10 commonly used emulsifying salts (ES) listed in the Code of Federal Regulations (21CFR133.179) for pasteurized process cheese were tested for their effect on the turbidity of a diluted milk system at different pH and protein concentrations to characterize the conditions that affect micellar structure. Emulsifying salt solutions were made by mixing the ES in a 1-in-20 dilution of water in skim milk ultrafiltrate (3 kDa molecular weight cut-off) to obtain ES concentrations from 0 to 248 mM. Skim milk was added to solutions containing nanopure water, skim milk ultrafiltrate, and a specific ES ranging in concentration from 0 to 248 mM and pH 5, 5.8, 6.8, 7.8, and 8.8. The turbidity of the samples was measured as the optical density at 400 nm immediately after mixing (time, t = 0), after 30 s (t = 30s), and after 30 min (t = 30min). Emulsifying salts were found to cause a decrease in the turbidity of the system, which was modeled using an exponential decay model, where C* represents a threshold salt concentration at which rapid dissociation occurs. At pH values 5.8 and 6.8, the ES caused the greatest decrease in turbidity of the diluted milk system. At pH 5, the ES had the least effect on the turbidity of the system. Sodium hexametaphosphate was found to have the strongest dissociative effect, with a C* value of 0.33 mM for t = 0 at pH 6.8. In contrast, the largest C* value calculated at pH 6.8 was monosodium phosphate at 278.22 mM. Increased time resulted in lower C* values. The model established for this study can be used to predict the dissociation of casein micelles in the presence of various types of ES. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Density, viscosity, and N2O solubility of aqueous amino acid salt and amine amino acid salt solutions

International Nuclear Information System (INIS)

Aronu, Ugochukwu E.; Hartono, Ardi; Svendsen, Hallvard F.

2012-01-01

Highlights: ► Density of amino acid salt and amine amino acid salt. ► Viscosity of amino acid salt and amine amino acid salt. ► Henry’s law constant/N 2 O solubility of amino acid salt and amine amino acid salt. ► Schumpe model. Correlations for density, viscosity, and N 2 O solubility. - Abstract: Physicochemical properties of aqueous amino acid salt (AAS), potassium salt of sarcosine (KSAR) and aqueous amine amino acid salt (AAAS), 3-(methylamino)propylamine/sarcosine (SARMAPA) have been studied. Densities of KSAR were measured for sarcosine mole fraction 0.02 to 0.25 for temperature range 298.15 K to 353.15 K, the viscosities were measured for 0.02 to 0.10 mole fraction sarcosine (293.15 K to 343.15 K) while the N 2 O solubilities were measured from 0.02 to 0.10 mole fraction sarcosine solutions (298.15 K to 363.15 K). Densities of SARMAPA were measured for sarcosine mole fraction 0.02 to 0.23 for temperature range (298.15 K to 353.15 K), viscosities were measured for 0.02 to 0.16 mole fraction sarcosine (293.15 K to 343.15 K) while the N 2 O solubilities were measured from 0.02 to 0.16 mole fraction sarcosine solutions (298.15 K to 343.15 K). Experimental results were correlated well with empirical correlations and N 2 O solubility results for KSAR were predicted adequately by a Schumpe model. The solubilities of N 2 O in AAS and AAAS are significantly lower than values for amines. The solubilities vary as: amine > AAAS > AAS.

Glyoxal and methylglyoxal Setschenow salting constants in sulfate, nitrate, and chloride solutions

DEFF Research Database (Denmark)

Waxman, Eleanor M.; Elm, Jonas; Kurtén, Theo

2015-01-01

Knowledge about Setschenow salting constants, KS, the exponential dependence of Henry's Law coefficients on salt concentration, is of particular importance to predict secondary organic aerosol (SOA) formation from soluble species in atmospheric waters with high salt concentrations, such as aerosols....... We have measured KS of glyoxal and methylglyoxal for the atmospherically relevant salts (NH4)2SO4, NH4NO3, NaNO3, and NaCl and find that glyoxal consistently "salts-in" (KS of -0.16, -0.06, -0.065, -0.1 molality(-1), respectively) while methylglyoxal "salts-out" (KS of +0.16, +0.075, +0.02, +0.......06 molality(-1)). We show that KS values for different salts are additive and present an equation for use in atmospheric models. Additionally, we have performed a series of quantum chemical calculations to determine the interactions between glyoxal/methylglyoxal monohydrate with Cl(-), NO3(-), SO4(2-), Na...

Sodium transport and distribution in sweet pepper during and after salt stress

NARCIS (Netherlands)

Blom-Zandstra, M.

2000-01-01

In hydroponic systems often saline water is used in nutrient solutions. Transpiration leads to a steady increase of the salt concentration. To avoid unfavourable salt conditions, solutions are renewed, regularly. So, plants are exposed to varying sodium concentrations. In this paper, the sodium

Meat batter production in an extended vane pump-grinder injecting curing salt solutions to reduce energy requirements: variation of curing salt amount injected with the solution.

Science.gov (United States)

Irmscher, Stefan B; Terjung, Eva-Maria; Gibis, Monika; Herrmann, Kurt; Kohlus, Reinhard; Weiss, Jochen

2017-01-01

The integration of a nozzle in an extended vane pump-grinder system may enable the continuous injection of curing salt solutions during meat batter production. The purpose of this work was to examine the influence of the curing salt amount injected with the solution (0-100%) on protein solubilisation, water-binding, structure, colour and texture of emulsion-type sausages. The amount of myofibrillar protein solubilised during homogenisation varied slightly from 33 to 36 g kg -1 . Reddening was not noticeably impacted by the later addition of nitrite. L * ranged from 66.9 ± 0.3 to 67.8 ± 0.3, a * from 10.9 ± 0.1 to 11.2 ± 0.1 and b * from 7.7 ± 0.1 to 8.0 ± 0.1. Although softer sausages were produced when only water was injected, firmness increased with increasing curing salt amount injected and was similar to the control when the full amount of salt was used. The substitution of two-thirds of ice with a liquid brine may enable energy savings due to reduced power consumptions of the extended vane pump-grinder system by up to 23%. The injection of curing salt solutions is feasible without affecting structure and colour negatively. This constitutes a first step towards of an 'ice-free' meat batter production allowing for substantial energy savings due to lower comminution work. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

A study on the structure of thorium salt solutions

International Nuclear Information System (INIS)

Magini, M.; Cabrini, A.; Di Bartolomeo, A.

1975-01-01

The structure of highly hydrolyzed thorium salt solutions has been investigated by large and small angle X-ray scattering techniques. The diffraction data obtained with large angle measurements show the presence in solution of microcrystalline particles with the thorium oxide structure. Particles larger than those were discovered by small angle measurements. A possible shape of these colloidal particles has been discussed

Effect of sodium phosphate salts on the thermodynamic properties of aqueous solutions of poly(ethylene oxide) 6000 at different temperatures

International Nuclear Information System (INIS)

Sadeghi, Rahmat; Hosseini, Rahim; Jamehbozorg, Bahman

2008-01-01

Precise density, sound velocity, water activity, and phase diagram measurements have been carried out on polyethylene oxide (PEO) in aqueous solutions of sodium di-hydrogen phosphate, di-sodium hydrogen phosphate, and tri-sodium phosphate over a range of temperatures at atmospheric pressure. The experimental density and sound velocity data are used to calculate the apparent specific volume and isentropic compressibility as a function of temperature and concentration. It was found that both of the apparent specific volume and isentropic compressibility of PEO in aqueous solutions increase by increasing temperature and charge on the anion of electrolytes. The results show that the slope of constant water activity lines increased with increasing the temperature and charge on the anion of electrolytes and the vapour pressure depression for an aqueous (PEO + sodium phosphate) system is more than the sum of those for the corresponding binary solutions. Furthermore, the effect of temperature and type of anion of salt on the salting-out effect of polyethylene oxide by sodium phosphate salts has been studied

Effect of sodium phosphate salts on the thermodynamic properties of aqueous solutions of poly(ethylene oxide) 6000 at different temperatures

Energy Technology Data Exchange (ETDEWEB)

Sadeghi, Rahmat [Department of Chemistry, University of Kurdistan, Sanandaj (Iran, Islamic Republic of)], E-mail: rahsadeghi@yahoo.com; Hosseini, Rahim; Jamehbozorg, Bahman [Department of Chemistry, University of Kurdistan, Sanandaj (Iran, Islamic Republic of)

2008-09-15

Precise density, sound velocity, water activity, and phase diagram measurements have been carried out on polyethylene oxide (PEO) in aqueous solutions of sodium di-hydrogen phosphate, di-sodium hydrogen phosphate, and tri-sodium phosphate over a range of temperatures at atmospheric pressure. The experimental density and sound velocity data are used to calculate the apparent specific volume and isentropic compressibility as a function of temperature and concentration. It was found that both of the apparent specific volume and isentropic compressibility of PEO in aqueous solutions increase by increasing temperature and charge on the anion of electrolytes. The results show that the slope of constant water activity lines increased with increasing the temperature and charge on the anion of electrolytes and the vapour pressure depression for an aqueous (PEO + sodium phosphate) system is more than the sum of those for the corresponding binary solutions. Furthermore, the effect of temperature and type of anion of salt on the salting-out effect of polyethylene oxide by sodium phosphate salts has been studied.

PRODUCTION OF INDUSTRY SALT WITH SEDIMENTATION – MICROFILTRATION PROCESS: OPTIMAZATION OF TEMPERATURE AND CONCENTRATION BY USING SURFACE RESPONSE METHODOLOGY

Directory of Open Access Journals (Sweden)

Widayat Widayat

2012-02-01

Full Text Available The salt of sodium chloride commonly used consumption in house , so as a raw material in industry. Thequality of salt depends on sodium chloride concentration. The objective of this research is obtained ofoptimum condition in production of salt industry by using sedimentation and microfiltration process. Theoptimization used surface response methodology and analysis by Statistica 6 software. The responseperceived is NaCl concentration in product. The experiments do by mixing stearic acid with NaOH solutionto product stearic sodium. Then, the solution mixed with sea water, so the white solid will be emerge, thereare stearic calcium and stearic magnesium. And so filtrate evaporated until to obtain salt. TheMathematical model for reduction of Ca2+ and Mg2+ are1 222 221 1 Y = 93,3185 + 1,0967 X + 0,1909 X +1,0682 X - 0,2333 X - 0,3376 X X , with maximum conversion is94,46% at temperature 82,42oC and stearic sodium concentration 14,16%(v/v. The maximum of NaClconcentration is 96,19% at temperature 81,54oC and stearic sodium concetration 13,11 %(v/v. Themathematical model for NaCl production is1 222 221 1 Y = 92,7596 − 0,3443 X − 3,3706 X + 2,9553 X - 0,9562 X - 1,9272 X X . The results of NaCl not yetfulfilled with SNI industry salt. The NaCl concetration in SNI is 98,5%. So, this process is nt aplicable forproductiob salt industry in Indonesia.

On the appearance of vorticity and gradient shear bands in wormlike micellar solutions of different CPCl/salt systems

Energy Technology Data Exchange (ETDEWEB)

Mütze, Annekathrin, E-mail: muetzea@ethz.ch; Heunemann, Peggy; Fischer, Peter [ETH Zürich, Institute of Food, Nutrition and Health, Schmelzbergstrasse 9, 8092 Zürich (Switzerland)

2014-11-01

Wormlike micellar salt/surfactant solutions (X-salicylate, cetylpyridinium chloride) are studied with respect to the applied shear stress, concentration, temperature, and composition of the counterions (X = lithium, sodium, potassium, magnesium, and calcium) of the salicylate salt solute to determine vorticity and gradient shear bands. A combination of rheological measurements, laser technique, video analysis, and rheo-small-angle neutron scattering allow for a detailed exploration of number and types of shear bands. Typical flow curves of the solutions show Newtonian, shear-thinning, and shear-thickening flow behavior. In the shear-thickening regime, the solutions show vorticity and gradient shear bands simultaneously, in which vorticity shear bands dominate the visual effect, while gradient shear bands always coexist and predominate the rheological response. It is shown that gradient shear bands change their phases (turbid, clear) with the same frequency as the shear rate oscillates, whereas vorticity shear bands change their phases with half the frequency of the shear rate. Furthermore, we show that with increasing molecular mass of the counterions the number of gradient shear bands increases, while the number of vorticity shear bands remains constant. The variation of temperature, shear stress, concentration, and counterions results in a predictable change in the rheological behavior and therefore allows adjustment of the number of vorticity shear bands in the shear band regime.

Dependence of osmotic pressure on solution properties

International Nuclear Information System (INIS)

Fritz, S.J.

1978-01-01

Hydrostatic pressure, temperature, salt concentration, and the chemical composition of the salt are parameters affecting solution properties. Pressure and temperature have little effect on osmosis, but osmotic pressure variations due to type of dissolved salt may be significant, especially at high concentrations. For a given salt solution, concentration variations cause large differences in osmotic pressure. A representative difference in concentration across a clay layer in a relatively shallow groundwater system might be 100 to 1,000 ppm. When expressed as ppm NaCl, this difference could cause a head difference of 0.8 to 8 meters of water if one of the rock bodies were closed to fluid escape

Structural evidence for solvent-stabilisation by aspartic acid as a mechanism for halophilic protein stability in high salt concentrations.

Science.gov (United States)

Lenton, Samuel; Walsh, Danielle L; Rhys, Natasha H; Soper, Alan K; Dougan, Lorna

2016-07-21

Halophilic organisms have adapted to survive in high salt environments, where mesophilic organisms would perish. One of the biggest challenges faced by halophilic proteins is the ability to maintain both the structure and function at molar concentrations of salt. A distinct adaptation of halophilic proteins, compared to mesophilic homologues, is the abundance of aspartic acid on the protein surface. Mutagenesis and crystallographic studies of halophilic proteins suggest an important role for solvent interactions with the surface aspartic acid residues. This interaction, between the regions of the acidic protein surface and the solvent, is thought to maintain a hydration layer around the protein at molar salt concentrations thereby allowing halophilic proteins to retain their functional state. Here we present neutron diffraction data of the monomeric zwitterionic form of aspartic acid solutions at physiological pH in 0.25 M and 2.5 M concentration of potassium chloride, to mimic mesophilic and halophilic-like environmental conditions. We have used isotopic substitution in combination with empirical potential structure refinement to extract atomic-scale information from the data. Our study provides structural insights that support the hypothesis that carboxyl groups on acidic residues bind water more tightly under high salt conditions, in support of the residue-ion interaction model of halophilic protein stabilisation. Furthermore our data show that in the presence of high salt the self-association between the zwitterionic form of aspartic acid molecules is reduced, suggesting a possible mechanism through which protein aggregation is prevented.

Modeling of Flow, Transport and Controlled Sedimentation Phenomena during Mixing of Salt Solutions in Complex Porous Formations

Science.gov (United States)

Skouras, Eugene D.; Jaho, Sofia; Pavlakou, Efstathia I.; Sygouni, Varvara; Petsi, Anastasia; Paraskeva, Christakis A.

2015-04-01

The deposition of salts in porous media is a major engineering phenomenon encountered in a plethora of industrial and environmental applications where in some cases is desirable and in other not (oil production, geothermal systems, soil stabilization etc). Systematic approach of these problems requires knowledge of the key mechanisms of precipitating salts within the porous structures, in order to develop new methods to control the process. In this work, the development and the solution of spatiotemporally variable mass balances during salt solution mixing along specific pores were performed. Both analytical models and finite differences CFD models were applied for the study of flow and transport with simultaneous homogeneous and heterogeneous nucleation (by crystal growth on the surface of the pores) in simple geometries, while unstructured finite elements and meshless methods were developed and implemented for spatial discretization, reconstruction, and solution of transport equations and homogeneous / heterogeneous reactions in more complex geometries. At initial stages of this work, critical problem parameters were identified, such as the characteristics of the porosity, the number of dissolved components, etc. The parameters were then used for solving problems which correspond to available experimental data. For each combination of ions and materials, specific data and process characteristics were included: (a) crystal kinetics (nucleation, growth rates or reaction surface rates of crystals, critical suspension concentrations), (b) physico-chemical properties (bulk density, dimensions of generated crystals, ion diffusion coefficients in the solution), (c) operating parameters (macroscopic velocity, flow, or pressure gradient of the solution, ion concentration) (d) microfluidic data (geometry, flow area), (e) porosity data in Darcy description (initial porosity, specific surface area, tortuosity). During the modeling of flow and transport in three

Capillary Ion Concentration Polarization for Power-Free Salt Purification

Science.gov (United States)

Park, Sungmin; Jung, Yeonsu; Cho, Inhee; Kim, Ho-Young; Kim, Sung Jae

2014-11-01

In this presentation, we experimentally and theoretically demonstrated the capillary based ion concentration polarization for power-free salt purification system. Traditional ion concentration polarization phenomenon has been studied for a decade for both fundamental nanoscale fluid dynamics and novel engineering applications such as desalination, preconcentration and energy harvesting devices. While the conventional system utilizes an external power source, the system based on capillary ion concentration polarization is capable of perm-selective ion transportation only by capillarity so that the same ion depletion zone can be formed without any external power sources. An ion concentration profile near the nanostructure was tracked using fluorescent probes and analyzed by solving the modified Nernst-Planck equation. As a result, the concentration in the vicinity of the nanostructure was at least 10 times lower than that of bulk electrolyte and thus, the liquid absorbed into the nanostructure had the low concentration. This mechanism can be used for the power free salt purification system which would be significantly useful in underdeveloped and remote area. This work was supported by Samsung Research Funding Center of Samsung Electronics under Project Number SRFC-MA1301-02.

Structure and ionic conductivity of block copolymer electrolytes over a wide salt concentration range

Science.gov (United States)

Chintapalli, Mahati; Le, Thao; Venkatesan, Naveen; Thelen, Jacob; Rojas, Adriana; Balsara, Nitash

Block copolymer electrolytes are promising materials for safe, long-lasting lithium batteries because of their favorable mechanical and ion transport properties. The morphology, phase behavior, and ionic conductivity of a block copolymer electrolyte, SEO mixed with LiTFSI was studied over a wide, previously unexplored salt concentration range using small angle X-ray scattering, differential scanning calorimetry and ac impedance spectroscopy, respectively. SEO exhibits a maximum in ionic conductivity at twice the salt concentration that PEO, the homopolymer analog of the ion-containing block, does. This finding is contrary to prior studies that examined a more limited range of salt concentrations. In SEO, the phase behavior of the PEO block and LiTFSI closely resembles the phase behavior of homopolymer PEO and LiTFSI. The grain size of the block copolymer morphology was found to decrease with increasing salt concentration, and the ionic conductivity of SEO correlates with decreasing grain size. Structural effects impact the ionic conductivity-salt concentration relationship in block copolymer electrolytes. SEO: polystyrene-block-poly(ethylene oxide); also PS-PEO LiTFSI: lithium bis(trifluoromethanesulfonyl imide

Impacts of different salt source and concentrations on germination and seedling growth of many pumpkin seeds used as rootstoch in Iran

Directory of Open Access Journals (Sweden)

Dadashpour Ahmad

2012-01-01

Full Text Available The effects of different salt sources (C Cl2, NaCl, and KCl and concentrations, as measured by electrical conductivity, (0, "control", 1, 3, 5, 7 and 9 dS m-1 on seed germination and seedling growth of “Ferro”, “Obez”, “RS 841” and “Strong Tosa F1” pumpkin varieties used as rootstock were investigated in this study. The results showed that germination rate, root length, shoot length, fresh root weight, dry root weight, fresh shoot weight and dry shoot weights tend to decrease when the electrical conductivity of the solution is higher than 5 dS m-1, independent of salt sources and in all of the varieties. Three days after seeding, a germination ratio of 5 % was obtained from RS 841 variety in all salt source and concentrations, while a germination ratio over 50 % was obtained in “Strong Tosa” variety for the same conditions except CaCl2 salt source. Nevertheless, seeds germinated in medium having high concentrations of CaCl2 had lower germination rate and poor seedling growth, compared to media having the same concentrations of NaCl and KCl. It was concluded that all of the varieties studied were more sensitive to the concentrations prepared using CaCl2 than that of the KCl, and NaCl.

Chain stiffness, salt valency, and concentration influences on titration curves of polyelectrolytes: Monte Carlo simulations

Science.gov (United States)

Carnal, Fabrice; Stoll, Serge

2011-01-01

Monte Carlo simulations have been used to study two different models of a weak linear polyelectrolyte surrounded by explicit counterions and salt particles: (i) a rigid rod and (ii) a flexible chain. We focused on the influence of the pH, chain stiffness, salt concentration, and valency on the polyelectrolyte titration process and conformational properties. It is shown that chain acid-base properties and conformational properties are strongly modified when multivalent salt concentration variation ranges below the charge equivalence. Increasing chain stiffness allows to minimize intramolecular electrostatic monomer interactions hence improving the deprotonation process. The presence of di and trivalent salt cations clearly promotes the chain degree of ionization but has only a limited effect at very low salt concentration ranges. Moreover, folded structures of fully charged chains are only observed when multivalent salt at a concentration equal or above charge equivalence is considered. Long-range electrostatic potential is found to influence the distribution of charges along and around the polyelectrolyte backbones hence resulting in a higher degree of ionization and a lower attraction of counterions and salt particles at the chain extremities.

Salt decontamination demonstration test results

International Nuclear Information System (INIS)

Snell, E.B.; Heng, C.J.

1983-06-01

The Salt Decontamination Demonstration confirmed that the precipitation process could be used for large-scale decontamination of radioactive waste sale solution. Although a number of refinements are necessary to safely process the long-term requirement of 5 million gallons of waste salt solution per year, there were no observations to suggest that any fundamentals of the process require re-evaluation. Major accomplishments were: (1) 518,000 gallons of decontaminated filtrate were produced from 427,000 gallons of waste salt solution from tank 24H. The demonstration goal was to produce a minimum of 200,000 gallons of decontaminated salt solution; (2) cesium activity in the filtrate was reduced by a factor of 43,000 below the cesium activity in the tank 24 solution. This decontamination factor (DF) exceeded the demonstration goal of a DF greater than 10,000; (3) average strontium-90 activity in the filtrate was reduced by a factor of 26 to less than 10 3 d/m/ml versus a goal of less than 10 4 d/m/ml; and (4) the concentrated precipitate was washed to a final sodium ion concentration of 0.15 M, well below the 0.225 M upper limit for DWPF feed. These accomplishments were achieved on schedule and without incident. Total radiation exposure to personnel was less than 350 mrem and resulted primarily from sampling precipitate slurry inside tank 48. 3 references, 6 figures, 2 tables

Molecular dynamics study of salt–solution interface: Solubility and surface charge of salt in water

International Nuclear Information System (INIS)

Kobayashi, Kazuya; Liang, Yunfeng; Matsuoka, Toshifumi; Sakka, Tetsuo

2014-01-01

The NaCl salt–solution interface often serves as an example of an uncharged surface. However, recent laser-Doppler electrophoresis has shown some evidence that the NaCl crystal is positively charged in its saturated solution. Using molecular dynamics (MD) simulations, we have investigated the NaCl salt–solution interface system, and calculated the solubility of the salt using the direct method and free energy calculations, which are kinetic and thermodynamic approaches, respectively. The direct method calculation uses a salt–solution combined system. When the system is equilibrated, the concentration in the solution area is the solubility. In the free energy calculation, we separately calculate the chemical potential of NaCl in two systems, the solid and the solution, using thermodynamic integration with MD simulations. When the chemical potential of NaCl in the solution phase is equal to the chemical potential of the solid phase, the concentration of the solution system is the solubility. The advantage of using two different methods is that the computational methods can be mutually verified. We found that a relatively good estimate of the solubility of the system can be obtained through comparison of the two methods. Furthermore, we found using microsecond time-scale MD simulations that the positively charged NaCl surface was induced by a combination of a sodium-rich surface and the orientation of the interfacial water molecules

Analysis of alloys and salt solutions by 'beta'-ray back-scattering

Energy Technology Data Exchange (ETDEWEB)

Bahadur, A; Maji, K D; Kumar, R [National Metallurgical Lab., Jamshedpur (India)

1975-07-01

This investigation reports the results of a study undertaken to assess the suitability of using the GM counter for measuring the intensity of ..beta..-backscattered radiation to determine the chemical composition of binary solid alloys, and aqueous salt solutions containing a metallic radical. The results indicate that the technique is not suitable for the determination of the composition of binary alloys since the error is in the range of 1.2 to 2.3 wt-% metal. The technique can be conveniently adapted for aqueous salt solutions where the maximum error is approximately 0.2 wt-% metal for metallic elements with atomic number greater than 20.

Blending Of Radioactive Salt Solutions In Million Gallon Tanks

Energy Technology Data Exchange (ETDEWEB)

Leishear, Robert A.; Lee, Si Y.; Fowley, Mark D.; Poirier, Michael R.

2012-12-10

Research was completed at Savannah River National Laboratory (SRNL) to investigate processes related to the blending of radioactive, liquid waste, salt solutions in 4920 cubic meter, 25.9 meter diameter storage tanks. One process was the blending of large salt solution batches (up to 1135 ? 3028 cubic meters), using submerged centrifugal pumps. A second process was the disturbance of a settled layer of solids, or sludge, on the tank bottom. And a third investigated process was the settling rate of sludge solids if suspended into slurries by the blending pump. To investigate these processes, experiments, CFD models (computational fluid dynamics), and theory were applied. Experiments were performed using simulated, non-radioactive, salt solutions referred to as supernates, and a layer of settled solids referred to as sludge. Blending experiments were performed in a 2.44 meter diameter pilot scale tank, and flow rate measurements and settling tests were performed at both pilot scale and full scale. A summary of the research is presented here to demonstrate the adage that, ?One good experiment fixes a lot of good theory?. Experimental testing was required to benchmark CFD models, or the models would have been incorrectly used. In fact, CFD safety factors were established by this research to predict full-scale blending performance. CFD models were used to determine pump design requirements, predict blending times, and cut costs several million dollars by reducing the number of required blending pumps. This research contributed to DOE missions to permanently close the remaining 47 of 51 SRS waste storage tanks.

Analysis of corrosion data for carbon steels in simulated salt repository brines and acid chloride solutions at high temperatures

International Nuclear Information System (INIS)

Diercks, D.R.; Hull, A.B.; Kassner, T.F.

1988-03-01

Carbon steel is currently the leading candidate material for fabrication of a container for isolation of high level nuclear waste in a salt repository. Since brine entrapped in the bedded salt can migrate to the container by several transport processes, corrosion is an important consideration in the long-term performance of the waste package. A detailed literature search was performed to compile relevant corrosion data for carbon steels in anoxic acid chloride solutions, and simulated salt repository brines at temperatures between ∼ 20 and 400 0 C. The hydrolysis of Mg 2+ ions in simulated repository brines containing high magnesium concentrations causes acidification at temperatures above 25 0 C, which, in turn, influences the protective nature of the magnetite corrosion product layer on carbon steel. The corrosion data for the steels were analyzed, and an analytical model for general corrosion was developed to calculate the amount of penetration (i.e., wall thinning) as a function of time, temperature, and the pressure of corrosion product hydrogen than can build up during exposure in a closed system (e.g., a sealed capsule). Both the temperature and pressure dependence of the corrosion rate of steels in anoxic acid chloride solutions indicate that the rate-controlling partial reaction is the cathodic reduction of water to form hydrogen. Variations in the composition and microstructure of the steels or the concentration of the ionic species in the chloride solutions (provided that they do not change the pH significantly) do not appear to strongly influence the corrosion rate

Simulation of NaCl and KCl mass transfer during salting of Prato cheese in brine with agitation: a numerical solution

Directory of Open Access Journals (Sweden)

E. Bona

2007-09-01

Full Text Available The association of dietary NaCl with arterial hypertension has led to a reduction in the levels of this salt in cheeses. For salting, KCl has been used as a partial substitute for NaCl, which cannot be completely substituted without affecting product acceptability. In this study a sensorially adequate saline solution (NaCl/KCl was simultaneously diffused during salting of Prato cheese in brine with agitation. The simultaneous multicomponent diffusion during the process was modeled with Fick’s second generalized law. The system of partial differential equations formed was solved by the finite element method (FEM. In the experimental data concentration the deviation for NaCl was of 7.3% and for KCl of 5.4%, both of which were considered acceptable. The simulation of salt diffusion will allow control and modulation of salt content in Prato cheese, permitting the prediction of final content from initial conditions.

Behavior of gellan in aqueous-salt solutions and oilfield saline water

Directory of Open Access Journals (Sweden)

Zhanar Nurakhmetova

2015-09-01

Full Text Available The influence of storage time and temperature on the behavior of low acyl gellan (LAG was studied by viscometry and 1H NMR spectroscopy without salt addition. The viscometric results revealed that the effectiveness of salts to enhance gelation of gellan changes in the following order: BaСl2>CaCl2»MgCl2>KCl>NaCl. The sol-gel and liquid-solid phase transitions of gellan solutions were observed upon addition of oilfield water containing 73 g L-1 of alkaline and alkaline earth metal ions. The effectiveness of salts to induce the separation of liquid and solid phases changes in the sequence: NaCl>KCl>MgCl2»CaCl2»BaСl2. The hydrodynamic behavior of 0.5 wt.% gellan solution injected into the sand pack model with high (20 Darcy and lower (2 Darcy permeability is useful to model the oil reservoirs in the process of enhanced oil recovery.

Lithium isotope effect in the extraction systems of polyethers: effect of salt concentration

International Nuclear Information System (INIS)

Fang Shengqiang; Fu Lian

1991-01-01

Separation factors of lithium isotopes at 20 deg C were determined in the extraction systems of B15C5-CHCl 3 /LiBr-H 2 O. The initial concentration of LiBr was controlled in the extent of more than 2 mol/l. It may be established that the increase of LiBr concentration causes a remarkable increase of the separation factor. The essence of this effect due to the change in salt concentration was discussed in connection with examination of relevant phenomena in literature. It can be concluded that the relationship between α and Cm, the concentration of lithium salt, is dependent on K Q and K P express respectively, lithium isotope exchange equilibrium constants between Li-crownether complex and hydrated lithium ion for lithium concentration less than 1-2 mol/l, and between lithium salt ion pair and hydrated lithium ion for lithium concentration more than 2 mol/l in aqueous phase

CO₂ Capture from Flue gas using Amino acid salt solutions

DEFF Research Database (Denmark)

Lerche, Benedicte Mai

to storage. Typical solvents for the process are based on aqueous solutions of alkanolamines, such as mono-ethanolamine (MEA), but their use implies economic disadvantages and environmental complications. Amino acid salt solutions have emerged as an alternative to the alkanolamines, partlybecause...... for measuring of CO2 solubility based on the semi-flow method. A validation study of CO2 solubility in aqueous solutions of MEA is presented. Chapter 5 focuses on the determination of the chemical compositions of the precipitations, which arise in the five amino acid salt solutions upon CO2 absorption...

Amino acid salt solutions as solvents in CO2 capture from flue gas

DEFF Research Database (Denmark)

Lerche, Benedicte Mai; Thomsen, Kaj; Stenby, Erling Halfdan

New solvents based on the salts of amino acids have emerged as an alternative to the alkanolamine solutions, for the chemical absorption of CO2 from flue gas. But only few studies on amino acids as CO2 capturing agents have been performed so far. One of the interesting features of amino acid salt...... solutions is their ability to form solid precipitates upon the absorption of CO2. The occurrence of crystallization offers the possibility of increasing the CO2 loading capacity of the solvent. However, precipitation can also have negative effect on the CO2 capture process. The chemical nature of the solid...... of glycine, taurine, and lysine, while in the case of proline, and glutamic acid, the precipitate was found to be bicarbonate. These results give an important contribution to further understanding the potential of amino acid salt solutions in CO2 capture from flue gas....

The salting-out of molibdoferrats(II from aqueous solutions by the organic solvents

Directory of Open Access Journals (Sweden)

Mykola V. Nikolenko

2016-12-01

Full Text Available The aim of this work was to develop a method for producing of molybdoferrate(II precipitates by salting-out them from aqueous solutions by means of organic solvents. Dependence of the composition of molybdoferrate(II precipitates on the pH of the reaction solutions was studied. Experiments on salting-out of molybdoferrate(II with various organic solvents were carried out. As a result it was found that the best reagent for the molybdoferrate(II salting-out is acetone. By its use, lowest quantity of the ammonium sulfate impurities was obtained. It is also of importance that by using of acetone the process of regeneration by distillation of the reaction solutions is characterized by the lowest energy consumption. A functional relationship between the solubility of molybdoferrates(II and dielectric constant of the medium was established. By increasing the dielectric constant of the solvent solubility of molybdoferrates(II rapidly increases. The linearized dependence ln(lnS–ln(1/e was proposed to predict the solubility of molybdoferrates(II in various aqueous-organic solutions.

Burner rig alkali salt corrosion of several high temperature alloys

Science.gov (United States)

Deadmore, D. L.; Lowell, C. E.

1977-01-01

The hot corrosion of five alloys was studied in cyclic tests in a Mach 0.3 burner rig into whose combustion chamber various aqueous salt solutions were injected. Three nickel-based alloys, a cobalt-base alloy, and an iron-base alloy were studied at temperatures of 700, 800, 900, and 1000 C with various salt concentrations and compositions. The relative resistance of the alloys to hot corrosion attack was found to vary with temperature and both concentration and composition of the injected salt solution. Results indicate that the corrosion of these alloys is a function of both the presence of salt condensed as a liquid on the surface and of the composition of the gas phases present.

Cast iron deterioration with time in various aqueous salt solutions

Indian Academy of Sciences (India)

Unknown

various aqueous salt solutions have been carried out using total immersion test ... circuit potential, Icorr, Tafel slopes, corrosion rate, have been calculated by standard methods. ..... Rao B V S 1980 in Maintenance for reliability (Bombay: Media.

The preparation of magnetite from iron(III) and iron(II) salt solutions

International Nuclear Information System (INIS)

Segal, D.L.

1980-10-01

Methods are described for the preparation of magnetite from iron(III) and iron(II) salt solutions at temperatures between 295 to 373 K. The effect of the reagent concentration, a chelating agent and different alkali-metal cations on the formation of magnetite has been investigated. The magnetite samples have been examined by X-ray diffraction, transmission electron microscopy, adsorption of nitrogen, emission spectroscopy, X-ray photoelectron spectroscopy and by determination of the point of zero charge. A review of previous work on the preparation of magnetite in an aqueous environment is also included. This work is relevant to the corrosion processes which can occur in the water coolant circuits of nuclear reactors. (author)

Thermal denitration of high concentration nitrate salts waste water

International Nuclear Information System (INIS)

Hwang, D. S.; Oh, J. H.; Choi, Y. D.; Hwang, S. T.; Park, J. H.; Latge, C.

2003-01-01

This study investigated the thermodynamic and the thermal decomposition properties of high concentration nitrate salts waste water for the lagoon sludge treatment. The thermodynamic property was carried out by COACH and GEMINI II based on the composition of nitrate salts waste water. The thermal decomposition property was carried out by TG-DTA and XRD. Ammonium nitrate and sodium nitrate were decomposed at 250 .deg. C and 730 . deg. C, respectively. Sodium nitrate could be decomposed at 450 .deg. C in the case of adding alumina for converting unstable Na 2 O into stable Na 2 O.Al 2 O 3 . The flow sheet for nitrate salts waste water treatment was proposed based on the these properties data. These will be used by the basic data of the process simulation

21 CFR 864.2875 - Balanced salt solutions or formulations.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Balanced salt solutions or formulations. 864.2875 Section 864.2875 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Cell And Tissue Culture Products § 864.2875...

Tetraphenylborate Solubility in High Ionic Strength Salt Solutions

International Nuclear Information System (INIS)

Serkiz, S.M.; Ginn, J.D.; Jurgensen, A.R.

1998-04-01

Solubility of sodium and potassium salts of the tetraphenylborate ion (TPB) in simulated Savannah River Site High Level Waste was investigated. Data generated from this study allow more accurate predictions of TPB solubility at the In-Tank Precipitation (ITP) facility. Because previous research showed large deviations in the observed solubility of TPB salts when compared with model predictions, additional data were generated to better understand the solubility of TPB in more complex systems of high ionic strength and those containing both potassium and sodium. These data allow evaluation of the ability of current models to accurately predict equilibrium TPB concentrations over the range of experimental conditions investigated in this study

Potentiometric Sensor for Real-Time Monitoring of Multivalent Ion Concentrations in Molten Salt

International Nuclear Information System (INIS)

Zink, Peter A.; Jue, Jan-Fong; Serrano, Brenda E.; Fredrickson, Guy L.; Cowan, Ben F.; Herrmann, Steven D.; Li, Shelly X.

2010-01-01

Electrorefining of spent metallic nuclear fuel in high temperature molten salt systems is a core technology in pyroprocessing, which in turn plays a critical role in the development of advanced fuel cycle technologies. In electrorefining, spent nuclear fuel is treated electrochemically in order to effect separations between uranium, noble metals, and active metals, which include the transuranics. The accumulation of active metals in a lithium chloride-potassium chloride (LiCl-KCl) eutectic molten salt electrolyte occurs at the expense of the UCl3-oxidant concentration in the electrolyte, which must be periodically replenished. Our interests lie with the accumulation of active metals in the molten salt electrolyte. The real-time monitoring of actinide concentrations in the molten salt electrolyte is highly desirable for controlling electrochemical operations and assuring materials control and accountancy. However, real-time monitoring is not possible with current methods for sampling and chemical analysis. A new solid-state electrochemical sensor is being developed for real-time monitoring of actinide ion concentrations in a molten salt electrorefiner. The ultimate function of the sensor is to monitor plutonium concentrations during electrorefining operations, but in this work gadolinium was employed as a surrogate material for plutonium. In a parametric study, polycrystalline sodium beta double-prime alumina (Na-β(double p rime)-alumina) discs and tubes were subject to vapor-phase exchange with gadolinium ions (Gd3+) using a gadolinium chloride salt (GdCl3) as a precursor to produce gadolinium beta double-prime alumina (Gd-β(double p rime)-alumina) samples. Electrochemical impedance spectroscopy and microstructural analysis were performed on the ion-exchanged discs to determine the relationship between ion exchange and Gd3+ ion conductivity. The ion-exchanged tubes were configured as potentiometric sensors in order to monitor real-time Gd3+ ion concentrations in

Heavy Metals in Salt and Water Samples from Maharloo Lake and their Comparison with Metal Concentrations in Samples from Sirjan, Lar, and Firoozabad Salt Mines

Directory of Open Access Journals (Sweden)

Farahnaz Sabet

2015-03-01

Full Text Available Maharloo Lake is one of the most important water ecosystems in Iran, which is nowadays exposed to multiple risks and threats due to poor water management, salt extraction, and heavy metal pollution. In this study, the concentrations of such heavy metals as chromium, copper, zinc, arsenic, cadmium, and lead in both water and salt samples collected from areas in the north and south of the lake were determined by atomic absorption (AA-670G after the samples had been digested. Results showed that metal concentrations in the salt samples taken from both the northern and southern areas had identical mean values in the order of Cr> Cu> As> Cd> Pb. An almost similar pattern was detected in metal concentrations in water samples taken from the same areas but with a slight difference in the way they were ordered (Cr> Cu> As> Pb> Cd. It was found that both water and salt samples collected from the northern areas had higher metal concentrations, except for that of Pb which was slightly lower. Comparison of the mean values of metal concentrations in the Salt Lake and those of Sirjan, Lar, and Firoozabad salt mines revealed that copper, cadmium, and lead had their highest concentrations in the Salt Lake while arsenic and chromium recorded their highest values in samples taken from Lar and Firoozabad salt mines, respectively. Based on these findings, it may be concluded that the increased metal concentrations observed in samples from both northern and southern areas of the lake are due to the sewage and effluents from urban, industrial, and hospital sources in Shiraz disposed into the lake as well as such other human activities as farming in the areas around the lake, especially in the northern stretches. These observations call for preventive measures to avoid further water quality degradation in the area.

Ageing behaviour of unary hydroxides in trivalent metal salt solutions

Indian Academy of Sciences (India)

LDH)-like phases on ageing in solutions of Al or Cr salts. This reaction is similar to acid leaching and proceeds by a dissolution–reprecipitation mechanism offering a simple method of LDH synthesis, with implications for the accepted theories of ...

Anion bridges drive salting out of a simple amphiphile from aqueous solution

International Nuclear Information System (INIS)

Bowron, D.T.; Finney, J.L.

2002-01-01

Neutron diffraction with isotope substitution has been used to determine the structural changes that occur on the addition of a simple salting-out agent to a dilute aqueous alcohol solution. The striking results obtained demonstrate a relatively simple process occurs in which interamphiphile anionic salt bridges are formed between the polar groups of the alcohol molecules. These ion bridges drive an increase in the exposure of the alcohol molecule nonpolar surface to the solvent water and hence point the way to their eventual salting out by the hydrophobic effect

Effects of sodium chloride salting and substitution with potassium chloride on whey expulsion of Cheddar cheese.

Science.gov (United States)

Lu, Y; McMahon, D J

2015-01-01

A challenge in manufacturing reduced-sodium cheese is that whey expulsion after salting decreases when less salt is applied. Our objectives were (1) to determine whether changing the salting method would increase whey syneresis when making a lower sodium cheese and (2) to better understand factors contributing to salt-induced curd syneresis. Unsalted milled Cheddar curds were salted using different salting intervals (5 or 10 min), different salting levels (20, 25, or 30g/kg), different numbers of applications when using only 20g/kg salt (1, 2, or 3 applications), and salting with the equivalent of 30g/kg NaCl using a 2:1 molar ratio of NaCl and KCl. Whey from these curds was collected every 5 or 10 min until 30 or 40 min after the start of salting, and curds were subsequently pressed for 3h. Additional trials were conducted in which salted milled Cheddar cheese curd was immersed at 22°C for 6h in various solutions to determine how milled curd pieces respond to different levels of salt and Ca. The use of 10-min intervals delayed whey syneresis without influencing total whey expulsion or cheese composition after pressing. Lowering the salt level reduced whey expulsion, resulting in cheeses with higher moisture and slightly lower pH. Adding salt faster did not increase whey expulsion in reduced-salt cheese. Partial substitution with KCl restored the extent of whey expulsion. When salted milled curd was immersed in a 30g/L salt solution, there was a net influx of salt solution into the curd and curd weight increased. When curd was immersed in 60g/L salt solution, a contraction of curd occurred. Curd shrinkage was more pronounced as the salt solution concentration was increased to 90 and 120g/L. Increasing the Ca concentration in test solutions (such that both serum and total Ca in the curd increased) also promoted curd contraction, resulting in lower curd moisture and pH and less weight gain by the curd. The proportion of Ca in the curd that was bound to the para

A comparison between evaporation ponds and evaporation surfaces as a source of the concentrated salt brine for salt gradient maintenance at Tajoura solar pond

International Nuclear Information System (INIS)

Ramadan, Abdulghani M.; Agha, Khairy R.; Abughres, M.

2012-01-01

One of the main problems that negatively affect the operation of salt gradient solar ponds and influence its thermal stability is the maintenance of salt gradient profile. Evaporation pond (EP) is designed to generate the salt which lost upward salt diffusion from the lower convective zone (LCZ) of the solar pond. Another attractive method is the evaporation surface facility (ES). Regions with moderate to high precipitation favor Evaporation Surface over Evaporation Ponds. Dry climates will generally favor Evaporation Ponds for the brine re-concentration. In previous studies [1-3], the authors have shown that the (EP) of Tajoura's Experimental Solar Pond (TESP) is under sized and can provide only about 30% of the salt required by a Salt Gradient Solar Pond (SGSP). The anticipated size of (EP) was estimated and presented in those studies under different design conditions, including Summer, Autumn and Spring designs, while the winter design was excluded due to the low rates of net evaporation during the winter season. In addition, the results presented were predicted for the first three years of operation. The daily variations of brine concentration in the (EP) of (TESP) and those based on different designs were predicted and discussed under different scenarios. The quantities of brine provided by the evaporation pond and that required by SGSP were predicted for both cases of surface water flushing (fresh water and sea-water) under the different design conditions as shown in Table 1. This paper investigates the differences between (EP) and (ES) both as a source for salt brine generation by evaporation. The effect of (EP) depth on the area ratio and daily variations of salt concentrations for three years of operation is shown. Results show that evaporation can be a reasonable method for salt brine generation. Reducing the depth of (EP) improves the capability of (EP) for brine re-concentration. It also increases the (EP) surface area for the same quantity of

Low molecular weight salts combined with fluorinated solvents for electrolytes

Science.gov (United States)

Tikhonov, Konstantin; Yip, Ka Ki; Lin, Tzu-Yuan; Lei, Norman; Guerrero-Zavala, Guillermo; Kwong, Kristie W.

2015-11-10

Provided are electrochemical cells and electrolytes used to build such cells. An electrolyte includes at least one salt having a molecular weight less than about 250. Such salts allow forming electrolytes with higher salt concentrations and ensure high conductivity and ion transport in these electrolytes. The low molecular weight salt may have a concentration of at least about 0.5M and may be combined with one or more other salts, such as linear and cyclic imide salts and/or methide salts. The concentration of these additional salts may be less than that of the low molecular weight salt, in some embodiments, twice less. The additional salts may have a molecular weight greater than about 250. The electrolyte may also include one or more fluorinated solvents and may be capable of maintaining single phase solutions at between about -30.degree. C. to about 80.degree. C.

Evaluation of chloride-ion-specific electrodes as in situ chemical sensors for monitoring total chloride concentration in aqueous solutions generated during the recovery of plutonium from molten salts used in plutonium electrorefining operations

International Nuclear Information System (INIS)

Smith, W.H.

1992-10-01

Two commercially available chloride-ion-specific electrodes (CLISEs), a solid-state type and a membrane type, were evaluated as potential in situ chemical sensors for determining total chloride ion concentration in mixed sodium chloride/potassium chloride/hydrochloric acid solutions generated during the recovery of plutonium from molten salts used in plutonium electrorefining operations. Because the response of the solid-state CLISE was closer than was the response of the membrane-type CLISE to the theoretical response predicted by the Nernst equation, the solid-state CLISE was selected for further evaluation. A detailed investigation of the characteristics of the chloride system and the corresponding CLISE response to concentration changes suggested four methods by which the CLISE could be used either as a direct, in situ sensor or as an indirect sensor through which an analysis could be performed on-line with a sample extracted from the process solution

Homemade sugar-salt solution for oral rehydration: knowledge of ...

African Journals Online (AJOL)

Up to 95% of these cases can be treated successfully with oral rehydration therapy. The aim of the study was to evaluate caregivers' knowledge of, attitudes to and use of homemade sugar and salt solution (SSS) in order to address the shortfalls. Differences between the knowledge, attitudes and practices in urban, rural and ...

Flotation of copper-bearing shale in solutions of inorganic salts and organic reagents

Directory of Open Access Journals (Sweden)

Ratajczak Tomasz

2017-01-01

Full Text Available Flotation data on copper-bearing shale in aqueous solutions of inorganic electrolytes (NaCl, Na2SO4, KPF6, NH4Cl and organic reagents (ethylamine, propylamine as frothers were presented and discussed. The relationships between shale flotation, surface tension of aqueous solution and foam height during bubbling with air in the flotation system were presented. It has been found that flotation of shale in the presence of inorganic salts the yield was directly proportional to the surface tension of the aqueous solution of salt and inversely proportional to the height of the foam. On the other hand, for organic reagents solutions (short chain amines, a reverse effect has been observed in relation to the inorganic compounds studied, that is the yield of copper-bearing shale flotation and the foam height were inversely proportional to the surface tension of the amine solution.

Conductometric investigation of salt-free solutions of polyriboguanylic acid

International Nuclear Information System (INIS)

Kozlov, A.G.; Davydova, O.V.; Kargov, S.I.

1993-01-01

Salt-free solutions of various ionic forms of polyriboguanylic acid (poly(G)) were studied by the methods of conductometry and spectroscopy of annular dichroism. The Manning approach was employed to calculate transport characteristics and structural parameters of poly(G) on the basis of spectra permit putting poly(G) salts in two groups: the first one comprising NH 4 + -, Rb + -, K + -, Na + -, the second one - Cs + -, and Li + -poly(G). The assumption is made that Li + and Cs + ions, bound with concrete groups of polyanion in a specific way, can promote formation of a stable structure different from the one observed in the presence of the first group counterions. 25 refs., 3 figs

Blending of Radioactive Salt Solutions in Million Gallon Tanks - 13002

International Nuclear Information System (INIS)

Leishear, Robert A.; Lee, Si Y.; Fowley, Mark D.; Poirier, Michael R.

2013-01-01

Research was completed at Savannah River National Laboratory (SRNL) to investigate processes related to the blending of radioactive, liquid waste, salt solutions in 4920 cubic meter, 25.9 meter diameter storage tanks. One process was the blending of large salt solution batches (up to 1135 - 3028 cubic meters), using submerged centrifugal pumps. A second process was the disturbance of a settled layer of solids, or sludge, on the tank bottom. And a third investigated process was the settling rate of sludge solids if suspended into slurries by the blending pump. To investigate these processes, experiments, CFD models (computational fluid dynamics), and theory were applied. Experiments were performed using simulated, non-radioactive, salt solutions referred to as supernates, and a layer of settled solids referred to as sludge. Blending experiments were performed in a 2.44 meter diameter pilot scale tank, and flow rate measurements and settling tests were performed at both pilot scale and full scale. A summary of the research is presented here to demonstrate the adage that, 'One good experiment fixes a lot of good theory'. Experimental testing was required to benchmark CFD models, or the models would have been incorrectly used. In fact, CFD safety factors were established by this research to predict full-scale blending performance. CFD models were used to determine pump design requirements, predict blending times, and cut costs several million dollars by reducing the number of required blending pumps. This research contributed to DOE missions to permanently close the remaining 47 of 51 SRS waste storage tanks. (authors)

Blending of Radioactive Salt Solutions in Million Gallon Tanks - 13002

Energy Technology Data Exchange (ETDEWEB)

Leishear, Robert A.; Lee, Si Y.; Fowley, Mark D.; Poirier, Michael R. [Savannah River National Laboratory, Aiken. S.C., 29808 (United States)

2013-07-01

Research was completed at Savannah River National Laboratory (SRNL) to investigate processes related to the blending of radioactive, liquid waste, salt solutions in 4920 cubic meter, 25.9 meter diameter storage tanks. One process was the blending of large salt solution batches (up to 1135 - 3028 cubic meters), using submerged centrifugal pumps. A second process was the disturbance of a settled layer of solids, or sludge, on the tank bottom. And a third investigated process was the settling rate of sludge solids if suspended into slurries by the blending pump. To investigate these processes, experiments, CFD models (computational fluid dynamics), and theory were applied. Experiments were performed using simulated, non-radioactive, salt solutions referred to as supernates, and a layer of settled solids referred to as sludge. Blending experiments were performed in a 2.44 meter diameter pilot scale tank, and flow rate measurements and settling tests were performed at both pilot scale and full scale. A summary of the research is presented here to demonstrate the adage that, 'One good experiment fixes a lot of good theory'. Experimental testing was required to benchmark CFD models, or the models would have been incorrectly used. In fact, CFD safety factors were established by this research to predict full-scale blending performance. CFD models were used to determine pump design requirements, predict blending times, and cut costs several million dollars by reducing the number of required blending pumps. This research contributed to DOE missions to permanently close the remaining 47 of 51 SRS waste storage tanks. (authors)

Concentration of involatile salts at evaporating water surfaces

International Nuclear Information System (INIS)

Gardner, G.C.

1988-02-01

Safety cases for the PWR often need to know how much of the soluble salts in the water will evaporate with the steam during flashing and when the steam is discharged to the atmosphere. Some ideal evaporating systems to give guidance. Simple formulae are derived for the surface concentration relative to the bulk concentration. An analysis is also presented which derives a formula for the mass transfer process in the steam due to both diffusion and convection, which arises from the evaporation process. The convection process will usually dominate. (author)

Hydronium-dominated ion transport in carbon-dioxide-saturated electrolytes at low salt concentrations in nanochannels

DEFF Research Database (Denmark)

Lund Jensen, Kristian; Kristensen, Jesper Toft; Crumrine, Andrew Michael

2011-01-01

the nanochannel conductance at low salt concentrations and identify a conductance minimum before saturation at a value independent of salt concentration in the dilute limit. Via the Poisson-Boltzmann equation, our model self-consistently couples chemical-equilibrium dissociation models of the silica wall...

DNA Duplex Length and Salt Concentration Dependence of Enthalpy−Entropy Compensation Parameters for DNA Melting

KAUST Repository

Starikov, E. B.

2009-08-20

Systematical differential calorimetry experiments on DNA oligomers with different lengths and placed in water solutions with various added salt concentrations may, in principle, unravel important information about the structure and dynamics of the DNA and their water-counterion surrounding. With this in mind, to reinterpret the most recent results of calorimetric experiments on DNA oligomers of such a kind, the recent enthalpy-entropy compensation theory has been used. It is demonstrated that the application of the latter could enable direct estimation of thermodynamic parameters of the microphase transitions connected to the changes in DNA dynamical regimes versus the length of the biopolymers and the ionic strengths of their water solutions, and this calls for much more systematical experimental and theoretical studies in this field. © 2009 American Chemical Society.

Microbial Succession And Biochemical Aspects Of Mandai Fermentation At Low Salt Concentration.

Directory of Open Access Journals (Sweden)

Hasrul Satria Nur

2009-04-01

Full Text Available Mandai isfermented food that traditionally made from the flesh of jack fruit (Arthocarphus champeden Spreg.. Usually mandai ismade as high salt concentration. However, the objective of this research is to study the succession and biochemicalaspects of microbials during fermentation at low salt concentration (10% w/v for 14 days. During the period offermentation microbial cell numbers and biochemical aspects were observed at the 3rd, 5th, 7th and 14th day. Total cellnumber of bacteria and yeast were measured by pour plate method. The measurement was also conducted on fleshbefore incubation. The biochemical aspect observation included the contents of reducing sugar, N-total, salt, and pH.The research results indicated that the pattern of microbial succession occurred the fermentation. Yeast cells grewdominantly (2.8 x 109 CFU/g on the 5th day fermentation but bacteria were dominant at the end (1.1 x 107 CFU/g. Thehighest decrease of reducing sugar and N-total contents were 0.240% at the 14th day and 0.159% at the 5th day,respectively. However, salt concentration was relatively stable and pH was varied within the range of 3.71-6.12 for thewhole period fermentation.

Effect of road salt application on seasonal chloride concentrations and toxicity in south-central Indiana streams.

Science.gov (United States)

Gardner, Kristin M; Royer, Todd V

2010-01-01

Contemporary information on road salt runoff is needed for management of water resources in regions experiencing urbanization and increased road density. We investigated seasonal Cl(-) concentrations among five streams in south-central Indiana that drained watersheds varying in degree of urbanization and ranging in size from 9.3 to 27 km(2). We also conducted acute toxicity tests with Daphnia pulex to assess the potential effects of the observed Cl(-) concentrations on aquatic life. Periods of elevated Cl(-) concentrations were observed during the winters of 2007-08 and 2008-09 at all sites except the reference site. The highest Cl(-) concentration observed during the study was 2100 mg L(-1) and occurred at the most urbanized site. The Cl(-) concentration at the reference site never exceeded 22 mg L(-1). The application of road salt caused large increases in stream Cl(-) concentrations, but the elevated Cl(-) levels did not appear to be a significant threat to aquatic life based on our toxicity testing. Only the most urbanized site showed evidence of salt retention within the watershed, whereas the other sites exported the road salt relatively quickly after its application, suggesting storm drains and impervious surfaces minimized interaction between soils and salt-laden runoff. During winter at these sites, the response in stream Cl(-) concentrations appeared to be controlled by the timing and intensity of road salt application, the magnitude of precipitation, and the occurrence of air temperatures that caused snowmelt and generated runoff.

Adaptive resolution simulation of an atomistic DNA molecule in MARTINI salt solution

NARCIS (Netherlands)

Zavadlav, J.; Podgornik, R.; Melo, M.n.; Marrink, S.j.; Praprotnik, M.

2016-01-01

We present a dual-resolution model of a deoxyribonucleic acid (DNA) molecule in a bathing solution, where we concurrently couple atomistic bundled water and ions with the coarse-grained MAR- TINI model of the solvent. We use our fine-grained salt solution model as a solvent in the inner shell

Synergy of boric acid and added salts in the catalytic dehydration of hexoses to 5-hydroxymethylfurfural in water

DEFF Research Database (Denmark)

Hansen, Thomas Steen; Mielby, Jerrik Jørgen; Riisager, Anders

2011-01-01

Boric acid and salts showed a synergistic effect on the dehydration of concentrated aqueous sugar solutions to yield 5-hydroxymethylfurfural.......Boric acid and salts showed a synergistic effect on the dehydration of concentrated aqueous sugar solutions to yield 5-hydroxymethylfurfural....

Dehydration of ethanol with salt extractive distillation-a comparative analysis between processes with salt recovery

Energy Technology Data Exchange (ETDEWEB)

Ligero, E.L.; Ravagnani, T.M.K. [Departamento de Engenharia de Sistemas Qumicos, Faculdade de Engenharia Qumica, Universidade Estadual de Campinas, Campinas, Sao Paulo (Brazil)

2003-07-01

Anhydrous ethanol can be obtained from a dilute aqueous solution of ethanol via extractive distillation with potassium acetate. Two process flowsheets with salt recovery were proposed. In the first, dilute ethanol is directly fed to a salt extractive distillation column and, after that, the salt is recovered in a multiple effect evaporator followed by a spray dryer. In the second, the concentrated ethanol from conventional distillation is fed to a salt extractive distillation column. In this case, salt is recovered in a single spray dryer. In both processes the recovered salt is recycled to be used in the extractive distillation column. Every component of each process was rigorously modeled and its behavior was simulated for a wide range of operating conditions. A global simulation was then carried out. The results show that the second process is more interesting in terms of energy consumption than the first. Furthermore, it would be easier to implement changes on existing benzene extractive anhydrous ethanol plants to convert them to more ecologically attractive concentrated ethanol feed processes. (author)

Process for using a saturated salt hydrate solution as a heat storing material in a latent heat storage device. Anvendelse av en mettet salthydratloesning som varme-lagringsmateriale i et latent varmemagasin

Energy Technology Data Exchange (ETDEWEB)

Wasel-Nielen, J.; Merkenich, K.; Gehrig, O.; Sommer, K.

1984-06-12

Disclosed is a process for preparing a salt composition having a phase transition heat greater than the heat capacity of water at a corresponding temperature, for charging a latent heat storage device. The process comprises the steps of providing an acid component of the salt hydrate; providing a base component of the salt hydrate, wherein at least one of the acid or base components comprises a liquid; and mixing the acid component and the base component together to cause a neutralization reaction. The acid and base components are mixed in a ratio and in respective concentrations to produce a salt hydrate solution saturated at the desired phase transition point. The claims concern the use of saturated salt hydrate solution with a certain phase transition heat produced in a particular way.

Non-isothermal desorption and nucleate boiling in a water-salt droplet LiBr

Directory of Open Access Journals (Sweden)

Misyura Sergey Ya.

2018-01-01

Full Text Available Experimental data on desorption and nucleate boiling in a droplet of LiBr-water solution were obtained. An increase in salt concentration in a liquid-layer leads to a considerable decrease in the rate of desorption. The significant decrease in desorption intensity with a rise of initial mass concentration of salt has been observed. Evaporation rate of distillate droplet is constant for a long time period. At nucleate boiling of a water-salt solution of droplet several characteristic regimes occur: heating, nucleate boiling, desorption without bubble formation, formation of the solid, thin crystalline-hydrate film on the upper droplet surface, and formation of the ordered crystalline-hydrate structures during the longer time periods. For the final stage of desorption there is a big difference in desorption rate for initial salt concentration, C0, 11% and 51%. This great difference in the rate of desorption is associated with significantly more thin solution film for C0 = 11% and higher heat flux.

Determination of activity coefficient of lanthanum chloride in molten LiCl-KCl eutectic salt as a function of cesium chloride and lanthanum chloride concentrations using electromotive force measurements

Energy Technology Data Exchange (ETDEWEB)

Bagri, Prashant, E-mail: prashant.bagri@utah.edu; Simpson, Michael F.

2016-12-15

The thermodynamic behavior of lanthanides in molten salt systems is of significant scientific interest for the spent fuel reprocessing of Generation IV reactors. In this study, the apparent standard reduction potential (apparent potential) and activity coefficient of LaCl{sub 3} were determined in a molten salt solution of eutectic LiCl-KCl as a function of concentration of LaCl{sub 3}. The effect of adding up to 1.40 mol % CsCl was also investigated. These properties were determined by measuring the open circuit potential of the La—La(III) redox couple in a high temperature molten salt electrochemical cell. Both the apparent potential and activity coefficient exhibited a strong dependence on concentration. A low concentration (0.69 mol %) of CsCl had no significant effect on the measured properties, while a higher concentration (1.40 mol %) of CsCl caused an increase (become more positive) in the apparent potential and activity coefficient at the higher range of LaCl{sub 3} concentrations.

Adaptive resolution simulation of salt solutions

International Nuclear Information System (INIS)

Bevc, Staš; Praprotnik, Matej; Junghans, Christoph; Kremer, Kurt

2013-01-01

We present an adaptive resolution simulation of aqueous salt (NaCl) solutions at ambient conditions using the adaptive resolution scheme. Our multiscale approach concurrently couples the atomistic and coarse-grained models of the aqueous NaCl, where water molecules and ions change their resolution while moving from one resolution domain to the other. We employ standard extended simple point charge (SPC/E) and simple point charge (SPC) water models in combination with AMBER and GROMOS force fields for ion interactions in the atomistic domain. Electrostatics in our model are described by the generalized reaction field method. The effective interactions for water–water and water–ion interactions in the coarse-grained model are derived using structure-based coarse-graining approach while the Coulomb interactions between ions are appropriately screened. To ensure an even distribution of water molecules and ions across the simulation box we employ thermodynamic forces. We demonstrate that the equilibrium structural, e.g. radial distribution functions and density distributions of all the species, and dynamical properties are correctly reproduced by our adaptive resolution method. Our multiscale approach, which is general and can be used for any classical non-polarizable force-field and/or types of ions, will significantly speed up biomolecular simulation involving aqueous salt. (paper)

Sealing of Anodised Aluminium Alloys with Rare Earth Metal Salt Solutions

OpenAIRE

Mansfield, C.; Chen, F.; Breslin, Carmel B.; Dull, D.

1998-01-01

Boric‐sulfuric acid anodized (BSAA) aluminum alloys have been sealed in hot solutions of cerium or yttrium salts. For comparison, sealing has also been performed in the presently used dilute chromate solution, boiling water, and a cold nickel fluoride solution. The corrosion resistance of the sealed BSAA Al alloys Al 2024, Al 6061, and Al 7075 has been evaluated by recording impedance spectra during exposure in 0.5 N NaCl for 7 days. Shorter or longer exposure times have also been used depend...

Magnesium degradation influenced by buffering salts in concentrations typical of in vitro and in vivo models.

Science.gov (United States)

Agha, Nezha Ahmad; Feyerabend, Frank; Mihailova, Boriana; Heidrich, Stefanie; Bismayer, Ulrich; Willumeit-Römer, Regine

2016-01-01

Magnesium and its alloys have considerable potential for orthopedic applications. During the degradation process the interface between material and tissue is continuously changing. Moreover, too fast or uncontrolled degradation is detrimental for the outcome in vivo. Therefore in vitro setups utilizing physiological conditions are promising for the material/degradation analysis prior to animal experiments. The aim of this study is to elucidate the influence of inorganic salts contributing to the blood buffering capacity on degradation. Extruded pure magnesium samples were immersed under cell culture conditions for 3 and 10 days. Hank's balanced salt solution without calcium and magnesium (HBSS) plus 10% of fetal bovine serum (FBS) was used as the basic immersion medium. Additionally, different inorganic salts were added with respect to concentration in Dulbecco's modified Eagle's medium (DMEM, in vitro model) and human plasma (in vivo model) to form 12 different immersion media. Influences on the surrounding environment were observed by measuring pH and osmolality. The degradation interface was analyzed by electron-induced X-ray emission (EIXE) spectroscopy, including chemical-element mappings and electron microprobe analysis, as well as Fourier transform infrared reflection micro-spectroscopy (FTIR). Copyright © 2015 Elsevier B.V. All rights reserved.

Influence of complexing on physicochemical properties of polymer-salt solutions. Vliyanie kompleksoobrazovaniya na fiziko-khimicheskie svojstva polimerno-solevykh rastvorov

Energy Technology Data Exchange (ETDEWEB)

Ostroushko, A A; Yushkova, S M; Koridze, N V; Skobkoreva, N V; Zhuravleva, L I; Palitskaya, T A; Antropova, S V; Ostroushko, I P [Ural' skij Gosudarstvennyj Univ., Sverdlovsk (Russian Federation) AN SSSR, Moscow (Russian Federation). Inst. Obshchej i Neorganicheskoj Khimii

1993-06-01

Using the methods of spectrophotometry, viscosimetry, conductometry the influence of salt-polymer complexing processes on physicochemical prperties of aqueous solutions of yttrium, barium, copper nitrates and formates with polyvinyl alcohol was studied. Change of dynamic viscosity, specific electric conductivity of solutions in the process of complexing was shown. Thermal effects of salt-polymer interaction were measured. It is shown that decrease of transition temperature of polymer to plastic state in films, temperature and effective activation energy of salt decomposition is also connected with complexing. Effective values of surface tension on the boundary with air are measured. Coefficients of cation diffusion in polymer-salt solutions are estimated.

Quantitative Visualization of Salt Concentration Distributions in Lithium-Ion Battery Electrolytes during Battery Operation Using X-ray Phase Imaging.

Science.gov (United States)

Takamatsu, Daiko; Yoneyama, Akio; Asari, Yusuke; Hirano, Tatsumi

2018-02-07

A fundamental understanding of concentrations of salts in lithium-ion battery electrolytes during battery operation is important for optimal operation and design of lithium-ion batteries. However, there are few techniques that can be used to quantitatively characterize salt concentration distributions in the electrolytes during battery operation. In this paper, we demonstrate that in operando X-ray phase imaging can quantitatively visualize the salt concentration distributions that arise in electrolytes during battery operation. From quantitative evaluation of the concentration distributions at steady states, we obtained the salt diffusivities in electrolytes with different initial salt concentrations. Because of no restriction on samples and high temporal and spatial resolutions, X-ray phase imaging will be a versatile technique for evaluating electrolytes, both aqueous and nonaqueous, of many electrochemical systems.

Salt disposition alternatives filtration at SRTC

International Nuclear Information System (INIS)

Walker, B. W.; Hobbs, D.

2000-01-01

Several of the prospective salt disposition alternative technologies require a monosodium titanate (MST) contact to remove strontium and actinides from inorganic salt solution feedstock. This feedstock also contains sludge solids from waste removal operations and may contain defoamers added in the evaporator systems. Filtration is required to remove the sludge and MST solids before sending the salt solution for further processing. This report describes testing performed using the Parallel Theological Experimental Filter (PREF). The PREF contains two single tube Mott sintered metal crossflow filters. For this test one filter was isolated so that the maximum velocities could be achieved. Previous studies showed slurries of MST and sludge in the presence of sodium tetraphenylborate (NaTPB) were filterable since the NaTPB slurry formed a filter cake which aided in removing the smaller MST and sludge particles. Some of the salt disposition alternative technologies do not use NaTPB raising the question of how effective crossflow filtration is with a feed stream containing only sludge and MST. Variables investigated included axial velocity, transmembrane pressure, defoamer effects, and solids concentration (MST and sludge). Details of the tests are outlined in the technical report WSRC-RP-98-O0691. Key conclusions from this study are: (1) Severe fouling of the Mott sintered metal filter did not occur with any of the solutions filtered. (2) The highest fluxes, in the range of .46 to 1.02 gpm/f 2 , were obtained when salt solution decanted from settled solids was fed to the filter. These fluxes would achieve 92 to 204 gpm filtrate production for the current ITP filters. The filtrate fluxes were close to the flux of 0.42 gpm/f 2 reported for In Tank Precipitation Salt Solution by Morrisey. (3) For the range of solids loading studied, the filter flux ranged from .04 to .17 gpm/f 2 which would result in a filtrate production rate of 9 to 31 gpm for the current HP filter. (4

Isolation and characterization of coagulant extracted from Moringa oleifera seed by salt solution.

Science.gov (United States)

Okuda, T; Baes, A U; Nishijima, W; Okada, M

2001-02-01

It is known that M. oleifera contains a natural coagulant in the seeds. In our previous research, the method using salt water to extract the active coagulation component from M. oleifera seeds was developed and compared with the conventional method using water. In this research, the active coagulation component was purified from a NaCl solution crude extract of Moringa oleifera seeds. The active component was isolated and purified from the crude extract through a sequence of steps that included salting-out by dialysis, removal of lipids and carbohydrates by homogenization with acetone, and anion exchange. Specific coagulation activity of the active material increased up to 34 times more than the crude extract after the ion exchange. The active component was not the same as that of water extract. The molecular weight was about 3000 Da. The Lowry method and the phenol-sulfuric acid method indicated that the active component was neither protein nor polysaccharide. The optimum pH of the purified active component for coagulation of turbidity was pH 8 and above. Different from the conventional water extracts, the active component can be used for waters with low turbidity without increase in the dissolved organic carbon concentration.

Molten Salt-Carbon Nanotube Thermal Energy Storage for Concentrating Solar Power Systems Final Report

Energy Technology Data Exchange (ETDEWEB)

Michael Schuller; Frank Little; Darren Malik; Matt Betts; Qian Shao; Jun Luo; Wan Zhong; Sandhya Shankar; Ashwin Padmanaban

2012-03-30

We demonstrated that adding nanoparticles to a molten salt would increase its utility as a thermal energy storage medium for a concentrating solar power system. Specifically, we demonstrated that we could increase the specific heat of nitrate and carbonate salts containing 1% or less of alumina nanoparticles. We fabricated the composite materials using both evaporative and air drying methods. We tested several thermophysical properties of the composite materials, including the specific heat, thermal conductivity, latent heat, and melting point. We also assessed the stability of the composite material with repeated thermal cycling and the effects of adding the nanoparticles on the corrosion of stainless steel by the composite salt. Our results indicate that stable, repeatable 25-50% improvements in specific heat are possible for these materials. We found that using these composite salts as the thermal energy storage material for a concentrating solar thermal power system can reduce the levelized cost of electricity by 10-20%. We conclude that these materials are worth further development and inclusion in future concentrating solar power systems.

Field evaporation test of uranium tailings solution

International Nuclear Information System (INIS)

Chandler, B.L.; Shepard, T.A.; Stewart, T.A.

1985-01-01

A field experiment was performed to observe the effect on evaporation rate of a uranium tailings impoundment pond water as salt concentration of the water increased. The duration of the experiment was long enough to cause maximum salt concentration of the water to be attained. The solution used in the experiment was tailings pond water from an inactive uranium tailings disposal site in the initial stages of reclamation. The solution was not neutralized. The initial pH was about 1.0 decreasing to a salt gel at the end of the test. The results of the field experiment show a gradual and slight decrease in evaporation efficiency. This resulted as salt concentrations increased and verified the practical effectiveness of evaporation as a water removal method. In addition, the physical and chemical nature of the residual salts suggest that no long-term stability problem would likely result due to their presence in the impoundment during or after reclamation

Concentration dependence of the partial volume, viscosity, and electric conductivity of solutions of lithium salts in aliphatic alcohols

International Nuclear Information System (INIS)

Eliseeva, O.V.; Golubev, V.V.

2003-01-01

Concentration dependence of partial volumes, electric conductivity and viscosity of lithium nitrate and chloride solutions in methanol, propanol, isopropanol, butanol, isobutanol, pentanol and isopentanol at 298.15 K were studied by the methods of densimetry, conductometry and viscosimetry. Structural specific features of the solutions studied are discussed on the basis of the calculated volumetric characteristics of the substance dissolved and solvent [ru

Small Column Ion Exchange Analysis for Removal of Cesium from SRS Low Curie Salt Solutions Using Crystalline Silicotitanate (CST) Resin

International Nuclear Information System (INIS)

ALEMAN, SEBASTIAN

2004-01-01

Savannah River Technology Center (SRTC) researchers modeled ion exchange removal of cesium from dissolved salt waste solutions. The results assist in evaluating proposed configurations for an ion exchange process to remove residual cesium from low curie waste streams. A process for polishing (i.e., removing small amounts) of cesium may prove useful should supernate draining fail to meet the Low Curie Salt (LCS) target limit of 0.1 Ci of Cs-137 per gallon of salt solution. Cesium loading isotherms and column breakthrough curves for Low Curie dissolved salt solutions were computed to provide performance predictions for various column designs

Thickening agent for flood water in secondary recovery of oil and for other aqueous salt solutions

Energy Technology Data Exchange (ETDEWEB)

Roth, H H

1966-04-14

Alkenyl-aromatic polymer sulfonates are good thickeners for some aqueous solutions, but addition of salts to such solutions reduces the desirable viscosity. High-molecular, water-soluble alkenyl-aromatic polymers which carry sulfonic acid or sulfonate groups substituted at the aromatic nuclei yield thickened solutions (e.g., for waterflooding) which are not influenced by the presence of water-soluble salts. Such polymers are derivatives of polyvinyltoluene, alone or in combination with about 5% acrylonitrile. It was also found that such thickening agents are less adsorbed on the rock matrix in a waterflood formation. (1 claim)

The salting-out effect and phase separation in aqueous solutions of tri-sodium citrate and 1-butyl-3-methylimidazolium bromide

International Nuclear Information System (INIS)

Sadeghi, Rahmat; Golabiazar, Roonak; Shekaari, Hemayat

2010-01-01

The aim of this work is to obtain further evidence about the salting-out effect produced by the addition of tri-sodium citrate to aqueous solutions of water miscible ionic liquid 1-butyl-3-methylimidazolium bromide ([C 4 mim][Br]) by evaluating the effect of tri-sodium citrate on the thermodynamic properties of aqueous solutions of this ionic liquid. Experimental measurements of density and sound velocity at different temperatures ranging from (288.15 to 308.15) K, the refractive index at 308.15 K and the liquid-liquid phase diagram at different temperatures ranging from (288.15 to 338.15) K for aqueous solutions containing 1-butyl-3-methylimidazolium bromide ([C 4 mim][Br]) and tri-sodium citrate (Na 3 Cit) are taken. The apparent molar volume of transfer of [C 4 mim][Br] from water to aqueous solutions of Na 3 Cit have positive values and it increases by increasing salt molality. Although at high IL molality, the apparent molar isentropic compressibility shows similar behaviour with that of the apparent molar volume. However at low concentrations of IL, the apparent molar isentropic compressibility of transfer of [C 4 mim][Br] from water to aqueous solutions of Na 3 Cit have negative values. The effects of temperature and the addition of Na 3 Cit and [C 4 mim][Br] on the liquid-liquid phase diagram of the investigated system have been studied. It was found that an increase in temperature caused the expansion of the one-phase region. The presence of Na 3 Cit triggers a salting-out effect, leading to significant upward shifts of the liquid-liquid de-mixing temperatures of the system. The effect of temperature on the phase-forming ability in the system investigated has been studied based on a salting-out coefficient obtained from fitting the binodal values to a Setschenow-type equation for each temperature. Based on cloud point values, the energetics of the clouding process have been estimated and it was found that both of entropy and enthalpy are the driving forces

Mobilization of arsenic, lead, and mercury under conditions of sea water intrusion and road deicing salt application

Science.gov (United States)

Sun, Hongbing; Alexander, John; Gove, Brita; Koch, Manfred

2015-09-01

Water geochemistry data from complexly designed salt-solution injection experiments in the laboratory, coastal aquifers of Bangladesh and Italy, taken from the literature, and two salted watersheds of New Jersey, US were collected and analyzed to study the geochemical mechanisms that mobilize As, Pb, and Hg under varied salting conditions. Overall, increased NaCl-concentrations in aquifers and soil are found to increase the release of Pb and Hg into the water. Reducing environments and possible soil dispersion by hydrated Na+ are found to lead to an increase of As-concentration in water. However, the application of a pure NaCl salt solution in the column injection experiment was found to release less As, Pb, and Hg initially from the soil and delay their concentration increase, when compared to the application of CaCl2 and NaCl mixed salts (at 6:4 weight ratio). The concentration correlation dendrogram statistical analyses of the experimental and field data suggest that the release of As, Hg, and Pb into groundwater and the soil solution depends not only on the salt level and content, but also on the redox condition, dissolved organic matter contents, competitiveness of other ions for exchange sites, and source minerals. With the ongoing over-exploration of coastal aquifers from increased pumping, continued sea-level rise, and increased winter deicing salt applications in salted watersheds of many inland regions, the results of this study will help understand the complex relation between the concentrations of As, Pb, and Hg and increased salt level in a coastal aquifer and in soils of a salted watershed.

The osmolyte xylitol reduces the salt concentration of airway surface liquid and may enhance bacterial killing

Science.gov (United States)

Zabner, Joseph; Seiler, Michael P.; Launspach, Janice L.; Karp, Philip H.; Kearney, William R.; Look, Dwight C.; Smith, Jeffrey J.; Welsh, Michael J.

2000-10-01

The thin layer of airway surface liquid (ASL) contains antimicrobial substances that kill the small numbers of bacteria that are constantly being deposited in the lungs. An increase in ASL salt concentration inhibits the activity of airway antimicrobial factors and may partially explain the pathogenesis of cystic fibrosis (CF). We tested the hypothesis that an osmolyte with a low transepithelial permeability may lower the ASL salt concentration, thereby enhancing innate immunity. We found that the five-carbon sugar xylitol has a low transepithelial permeability, is poorly metabolized by several bacteria, and can lower the ASL salt concentration in both CF and non-CF airway epithelia in vitro. Furthermore, in a double-blind, randomized, crossover study, xylitol sprayed for 4 days into each nostril of normal volunteers significantly decreased the number of nasal coagulase-negative Staphylococcus compared with saline control. Xylitol may be of value in decreasing ASL salt concentration and enhancing the innate antimicrobial defense at the airway surface.

Solid solutions of platinum(II) and palladium(II) oxalato-complex salt as precursors of nanoalloys

Science.gov (United States)

Zadesenets, A. V.; Asanova, T. I.; Vikulova, E. S.; Filatov, E. Yu.; Plyusnin, P. E.; Baidina, I. A.; Asanov, I. P.; Korenev, S. V.

2013-03-01

A solid solution of platinum (II) and palladium (II) oxalato-complex salt, (NH4)2[Pt0.5Pd0.5(C2O4)2]·2H2O, has been synthesized and studied as a precursor for preparing bimetallic PtPd nanoparticles through its thermal decomposition. The smallest homogenous bimetallic PtPd nanoparticles were found to form in hydrogen and helium atmospheres. The annealing temperature and time have low effect on the bimetallic particles size. Comparative analysis of structural and thermal properties of the solid solution and individual Pt, Pd oxalato-complex salts was performed to investigate a mechanism of thermal decomposition of (NH4)2[Pt0.5Pd0.5(C2O4)2]·2H2O. Based on in situ X-ray photoemission spectroscopy investigation it was proposed a mechanism of formation of bimetallic PtPd nanoparticles from the solid-solution oxalato-complex salt during thermal decomposition.

Adaptation to high salt concentrations in halotolerant/ halophilic fungi: a molecular perspective

Directory of Open Access Journals (Sweden)

Ana ePlemenitas

2014-05-01

Full Text Available Molecular studies of salt tolerance of eukaryotic microorganisms have until recently been limited to the baker’s yeast Saccharomyces cerevisiae and a few other moderately halotolerant yeast. Discovery of the extremely halotolerant and adaptable fungus Hortaea werneckii and the obligate halophile Wallemia ichthyophaga introduced two new model organisms into studies on the mechanisms of salt tolerance in eukaryotes. H. werneckii is unique in its adaptability to fluctuations in salt concentrations, as it can grow without NaCl as well as in the presence of up to 5 M NaCl. On the other hand, W. ichthyophaga requires at least 1.5 M NaCl for growth, but also grows in up to 5 M NaCl. Our studies have revealed the novel and intricate molecular mechanisms used by these fungi to combat high salt concentrations, which differ in many aspects between the extremely halotolerant H. werneckii and the halophilic W. ichthyophaga. Specifically, the high osmolarity glycerol signalling pathway that is important for sensing and responding to increased salt concentrations is here compared between H. werneckii and W. ichthyophaga. In both of these fungi, the key signalling components are conserved, but there are structural and regulation differences between these pathways in H. werneckii and W. ichthyophaga. We also address differences that have been revealed from analysis of their newly sequenced genomes. The most striking characteristics associated with H. werneckii are the large genetic redundancy, the expansion of genes encoding metal cation transporters, and a relatively recent whole genome duplication. In contrast, the genome of W. ichthyophaga is very compact, as only 4,884 protein-coding genes are predicted, which cover almost three quarters of the sequence. Importantly, there has been a significant increase in their hydrophobins, cell-wall proteins that have multiple cellular functions.

Ion clustering in aqueous salt solutions near the liquid/vapor interface

Directory of Open Access Journals (Sweden)

J.D. Smith

2016-03-01

Full Text Available Molecular dynamics simulations of aqueous NaCl, KCl, NaI, and KI solutions are used to study the effects of salts on the properties of the liquid/vapor interface. The simulations use the models which include both charge transfer and polarization effects. Pairing and the formation of larger ion clusters occurs both in the bulk and surface region, with a decreased tendency to form larger clusters near the interface. An analysis of the roughness of the surface reveals that the chloride salts, which have less tendency to be near the surface, have a roughness that is less than pure water, while the iodide salts, which have a greater surface affinity, have a larger roughness. This suggests that ions away from the surface and ions near the surface affect the interface in opposite ways.

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.

Ionic relaxation in PEO/PVDF-HFP-LiClO4 blend polymer electrolytes: dependence on salt concentration

Science.gov (United States)

Das, S.; Ghosh, A.

2016-06-01

In this paper, we have studied the effect of LiClO4 salt concentration on the ionic conduction and relaxation in poly ethylene oxide (PEO) and poly (vinylidene fluoride hexafluoropropylene) (PVDF-HFP) blend polymer electrolytes, in which the molar ratio of ethylene oxide segments to lithium ions (R  =  EO: Li) has been varied between 3 and 35. We have observed two phases in the samples containing low salt concentrations (R  >  9) and single phase in the samples containing high salt concentrations (R  ⩽  9). The scanning electron microscopic images indicate that there exists no phase separation in the blend polymer electrolytes. The temperature dependence of the ionic conductivity shows two slopes corresponding to high and low temperatures and follows Arrhenius relation for the samples containing low salt concentrations (R  >  9). The conductivity relaxation as well as the structural relaxation has been clearly observed at around 104 Hz and 106 Hz for these concentrations of the blended electrolytes. However, a single conductivity relaxation peak has been observed for the compositions with R  ⩽  9. The scaling of the conductivity spectra shows that the relaxation mechanism is independent of temperature, but depends on salt concentration.

Calculation of amorphous silica solubilities at 25° to 300°C and apparent cation hydration numbers in aqueous salt solutions using the concept of effective density of water

Science.gov (United States)

Fournier, Robert O.; Williams, Marshall L.

1983-01-01

The solubility of amorphous silica in aqueous salt solutions at 25° to 300°C can be calculated using information on its solubility in pure water and a model in which the activity of water in the salt solution is defined to equal the effective density. pe, of “free” water in that solution. At temperatures of 100°C and above, pe closely equals the product of the density of the solution times the weight fraction of water in the solution. At 25°C, a correction parameter must be applied to pe that incorporates a term called the apparent cation hydration number, h. Because of the many assumptions and other uncertainties involved in determining values of h, by the model used here, the reported numbers are not necessarily real hydration numbers even though they do agree with some published values determined by activity and diffusion methods. Whether or not h is a real hydration number, it would appear to be useful in its inclusion within a more extensive activity coefficient term that describes the departure of silica solubilities in concentrated salt solutions from expected behavior according to the model presented here. Values of h can be calculated from measured amorphous silica solubilities in salt solutions at 25°C provided there is no complexing of dissolved silica with the dissolved salt, or if the degree of complexing is known. The previously postulated aqueous silica-sulfate complexing in aqueous Na2SO4 solutions is supported by results of the present effective density of water model

Estimation of Concrete Corrosion Due to Attack of Chloride Salt

Directory of Open Access Journals (Sweden)

V. V. Babitski

2005-01-01

Full Text Available The paper provides results of experimental concrete research under conditions of concentrated chloride salt solutions. General principles of forecasting concrete corrosion resistance under salt physical corrosion are given in the paper. Analytical dependences for quantitative estimation of corroded concrete have been obtained.

Characterization of Laboratory Prepared Concrete Pastes Exposed to High Alkaline and High Sodium Salt Solutions

Energy Technology Data Exchange (ETDEWEB)

Langton, C. A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2016-06-30

The objective of this study was to identify potential chemical degradation mechanisms for the Saltstone Disposal Unit (SDU) concretes, which over the performance life of the structures may be exposed to highly alkaline sodium salt solutions containing sulfate, hydroxide, and other potentially corrosive chemicals in salt solution and saltstone flush water, drain water, leachate and / or pore solution. The samples analyzed in this study were cement pastes prepared in the SIMCO Technologies, Inc. concrete laboratory. They were based on the paste fractions of the concretes used to construct the Saltstone Disposal Units (SDUs). SDU 1 and 4 concrete pastes were represented by the PV1 test specimens. The paste in the SDU 2, 3, 5, and 6 concrete was represented by the PV2 test specimens. SIMCO Technologies, Inc. selected the chemicals and proportions in the aggressive solutions to approximate proportions in the saltstone pore solution [2, 3, 5, and 6]. These test specimens were cured for 56 days in curing chamber before being immersed in aggressive solutions. After exposure, the samples were frozen to prevent additional chemical transport and reaction. Selected archived (retrieved from the freezer) samples were sent to the Savannah River National Laboratory (SRNL) for additional characterization using x-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive x-ray (EDX) spectroscopy. Characterization results are summarized in this report. In addition, a correlation between the oxide composition of the pastes and their chemical durability in the alkaline salt solutions is provided.

Effect of solution concentration on sealing treatment of Mg-Al hydrotalcite film on AZ91D Mg alloy

Directory of Open Access Journals (Sweden)

Qiangsheng Dong

2017-09-01

Full Text Available Cerium-based sealing treatment was developed for Mg-Al hydrotalcite film on AZ91D Mg alloy, and the influence of cerium salt solution was investigated to modify the surface integrity and corrosion resistance. Scanning electron microscope (SEM and X-ray diffraction (XRD measurements were carried out to analyze the surface morphology and phase composition. The corrosion resistance of Mg-Al hydrotalcite film after sealing treatment was evaluated by the polarization curve and electrochemical impedance spectroscopy (EIS tests. The results showed that lower concentration of Ce-containing solution was beneficial to seal the micro-cracks on Mg-Al hydrotalcite film, and improve the surface integrity and corrosion resistance; higher concentration of Ce-containing solution could seal fewer micro-cracks, and the corrosion resistance was decreased owing to the disintegration of Mg-Al hydrotalcite film.

The solubilities of significant organic compounds in HLW tank supernate solutions -- FY 1995 progress report

International Nuclear Information System (INIS)

Barney, G.S.

1996-01-01

At the Hanford Site organic compounds were measured in tank supernate simulant solutions during FY 1995. This solubility information will be used to determine if these organic salts could exist in solid phases (saltcake or sludges) in the waste where they might react violently with the nitrate or nitrite salts present in the tanks. Solubilities of sodium glycolate, succinate, and caproate salts; iron and aluminum and butylphosphate salts; and aluminum oxalate were measured in simulated waste supernate solutions at 25 degree C, 30 degree C, 40 degree C, and 50 degree C. The organic compounds were selected because they are expected to exist in relatively high concentrations in the tanks. The solubilities of sodium glycolate, succinate, caproate, and butylphosphate in HLW tank supernate solutions were high over the temperature and sodium hydroxide concentration ranges expected in the tanks. High solubilities will prevent solid sodium salts of these organic acids from precipitating from tank supernate solutions. The total organic carbon concentrations (YOC) of actual tank supernates are generally much lower than the TOC ranges for simulated supernate solutions saturated (at the solubility limit) with the organic salts. This is so even if all the dissolved carbon in a given tank and supernate is due to only one of these eight soluble compounds (an unlikely situation). Metal ion complexes of and butylphosphate and oxalate in supernate solutions were not stable in the presence of the hydroxide concentrations expected in most tanks. Iron and aluminum dibutylphosphate compounds reacted with hydroxide to form soluble sodium dibutylphosphate and precipitated iron and aluminum hydroxides. Aluminum oxalate complexes were also not stable in the basic simulated supernate solutions. Solubilities of all the organic salts decrease with increasing sodium hydroxide concentration because of the common ion effect of Na+. Increasing temperatures raised the solubilities of the organic

Length scale dependence of the dynamic properties of hyaluronic acid solutions in the presence of salt.

Science.gov (United States)

Horkay, Ferenc; Falus, Peter; Hecht, Anne-Marie; Geissler, Erik

2010-12-02

In solutions of the charged semirigid biopolymer hyaluronic acid in salt-free conditions, the diffusion coefficient D(NSE) measured at high transfer momentum q by neutron spin echo is more than an order of magnitude smaller than that determined by dynamic light scattering, D(DLS). This behavior contrasts with neutral polymer solutions. With increasing salt content, D(DLS) approaches D(NSE), which is independent of ionic strength. Contrary to theoretical expectation, the ion-polymer coupling, which dominates the low q dynamics of polyelectrolyte solutions, already breaks down at distance scales greater than the Debye-Hückel length.

Magnesium degradation influenced by buffering salts in concentrations typical of in vitro and in vivo models

International Nuclear Information System (INIS)

Agha, Nezha Ahmad; Feyerabend, Frank; Mihailova, Boriana; Heidrich, Stefanie; Bismayer, Ulrich; Willumeit-Römer, Regine

2016-01-01

Magnesium and its alloys have considerable potential for orthopedic applications. During the degradation process the interface between material and tissue is continuously changing. Moreover, too fast or uncontrolled degradation is detrimental for the outcome in vivo. Therefore in vitro setups utilizing physiological conditions are promising for the material/degradation analysis prior to animal experiments. The aim of this study is to elucidate the influence of inorganic salts contributing to the blood buffering capacity on degradation. Extruded pure magnesium samples were immersed under cell culture conditions for 3 and 10 days. Hank's balanced salt solution without calcium and magnesium (HBSS) plus 10% of fetal bovine serum (FBS) was used as the basic immersion medium. Additionally, different inorganic salts were added with respect to concentration in Dulbecco's modified Eagle's medium (DMEM, in vitro model) and human plasma (in vivo model) to form 12 different immersion media. Influences on the surrounding environment were observed by measuring pH and osmolality. The degradation interface was analyzed by electron-induced X-ray emission (EIXE) spectroscopy, including chemical-element mappings and electron microprobe analysis, as well as Fourier transform infrared reflection micro-spectroscopy (FTIR). - Highlights: • Influence of blood buffering salts on magnesium degradation was studied. • CaCl_2 reduced the degradation rate by Ca–PO_4 layer formation. • MgSO_4 influenced the morphology of the degradation interface. • NaHCO_3 induced the formation of MgCO_3 as a degradation product

Statistical mechanics of protein solutions

NARCIS (Netherlands)

Prinsen, P.

2007-01-01

We study theoretically thermodynamic properties of spherical globular proteins in aqueous solution with added monovalent salt. We show how one can determine an effective interaction potential between the proteins from experimental data as a function of salt concentration and we apply this to the

Methane-steam reforming by molten salt - membrane reactor using concentrated solar thermal energy

International Nuclear Information System (INIS)

Watanuki, K.; Nakajima, H.; Hasegawa, N.; Kaneko, H.; Tamaura, Y.

2006-01-01

By utilization of concentrated solar thermal energy for steam reforming of natural gas, which is an endothermic reaction, the chemical energy of natural gas can be up-graded. The chemical system for steam reforming of natural gas with concentrated solar thermal energy was studied to produce hydrogen by using the thermal storage with molten salt and the membrane reactor. The original steam reforming module with hydrogen permeable palladium membrane was developed and fabricated. Steam reforming of methane proceeded with the original module with palladium membrane below the decomposition temperature of molten salt (around 870 K). (authors)

In vitro selection of induced mutants to salt-tolerance: Inducible gene regulation for salt tolerance

Energy Technology Data Exchange (ETDEWEB)

Winicov, I [Department of Microbiology and Biochemistry, Univ. of Nevada-Reno, Reno, NV (United States)

1997-07-01

A selection protocol to obtain salt tolerant calli, followed by regeneration and progeny-test of the regenerated plants for salt tolerance in rice was investigated. Callus cultures were initiated from salt-sensitive US elite rice lines and cv. `Pokkali`. Salt-tolerant cell lines were selected from these by a single step selection procedure. The selected salt-tolerant lines grew well on medium with {+-} 0.5% or 1% NaCl, while the parent lines occasionally survived, but did not grow at these salt concentrations. Plants were regenerated from these cell lines through different passages on medium containing salt. Seed was collected from the regenerated plants and salt tolerance of R2 seedlings was compared with those regenerated without salt selection. Salt-tolerance was measured by survival and productive growth of newly germinated seedlings in Hoagland solution with 0.3% and 0.5% NaCl for 4 weeks. Heritable improvement in salt tolerance was obtained in R2 seedlings from one plant regenerated after 5 months selection. Survival and growth of these seedlings was equivalent to that from `Pokkali` seedlings. These results show that cellular tolerance can provide salt-tolerance in rice plants. (author). 6 refs, 2 tabs.

In vitro selection of induced mutants to salt-tolerance: Inducible gene regulation for salt tolerance

International Nuclear Information System (INIS)

Winicov, I.

1997-01-01

A selection protocol to obtain salt tolerant calli, followed by regeneration and progeny-test of the regenerated plants for salt tolerance in rice was investigated. Callus cultures were initiated from salt-sensitive US elite rice lines and cv. 'Pokkali'. Salt-tolerant cell lines were selected from these by a single step selection procedure. The selected salt-tolerant lines grew well on medium with ± 0.5% or 1% NaCl, while the parent lines occasionally survived, but did not grow at these salt concentrations. Plants were regenerated from these cell lines through different passages on medium containing salt. Seed was collected from the regenerated plants and salt tolerance of R2 seedlings was compared with those regenerated without salt selection. Salt-tolerance was measured by survival and productive growth of newly germinated seedlings in Hoagland solution with 0.3% and 0.5% NaCl for 4 weeks. Heritable improvement in salt tolerance was obtained in R2 seedlings from one plant regenerated after 5 months selection. Survival and growth of these seedlings was equivalent to that from 'Pokkali' seedlings. These results show that cellular tolerance can provide salt-tolerance in rice plants. (author). 6 refs, 2 tabs

Research on electrochemical methods for concentration measurement of dissolved ion in molten salt to apply to electrolytic process control. Innovative research adopted in 2002 fiscal year

International Nuclear Information System (INIS)

Nagai, Takayuki

2005-03-01

The purpose of this research is to establish the online (in-situ) technique for concentration measuring of dissolved ion in the molten salt, and this technique is due to the electrochemical method for the concentration measuring of dissolved ion in solutions like the polarization curve measurement. This research executed the following four items. 1) Examination of possibility for concentration measuring of dissolved ion in molten salt by cyclic voltammetry. 2) Examination of possibility for concentration measuring of dissolved ion in molten salt by various electrochemical methods. 3) Examination of suitable electrochemical method for concentration measuring of dissolved ion. 4) Confirmation of selected electrochemical method for concentration measuring of dissolved ion. It has been understood that the differential pulse voltammetry (DPV) is a promising electrochemical technique for the concentration measuring of dissolved ion in the molten salt as a result of this research. An appropriate measurement condition is as follows, the potential sweep rate is -0.1 V/s, the pulse cycle is 0.1 s, the pulse width is 10 ms, and the pulse voltage is 50 mV. As for the electrodes, the platinum working electrode, the glassy carbon counter electrode, and silver/silver chloride reference electrode are suitable. Moreover, the molar absorptivities of U 3+ , U 4+ , UO 2 + , UO 2 2+ , and the standard redox potentials of couples of U 4+ /U 3+ and UO 2 2+ /UO 2 + were acquired as a basic data of the uranium and the uranyl ion in molten NaCl-2CsCl. (author)

Interaction Free Energies of Eight Sodium Salts and a Phosphatidylcholine Membrane

DEFF Research Database (Denmark)

Wang, C. H.; Ge, Y.; Mortensen, J.

2011-01-01

Many recent reports have discussed specific effects of anions on the properties of lipid membranes and possible roles of such effects within biochemistry. One key parameter in both theoretical and experimental treatments of membrane-salt interactions is the net affinity, that is, the free energy...... salts by dialysis equilibrium measurements. This method provides model free thermodynamic data and allows investigations in the dilute concentration range where solution nonideality and perturbation of membrane structure is limited. The transfer free energy of DMPC from water to salt solutions, Delta mu...

Hofmeister effect of salt mixtures on thermo-responsive poly(propylene oxide)

DEFF Research Database (Denmark)

Moghaddam, Saeed Zajforoushan; Thormann, Esben

2015-01-01

of aqueous solutions of poly(propylene oxide) is affected by mixtures of ions with different location in the Hofmeister series. Our results show that the Hofmeister effects of pure salt species are not always linearly additive and that the relative effect of some ions can be reversed depending...... on the composition of the salt mixture as well as by the absolute and relative concentration of the different species. We suggest that these results can lead to a better understanding of the potential role of the Hofmeister effect in regulation of biological processes, which does always take place in salt mixtures...... rather than solutions containing just single salt species....

Chemical concentration of a new natural spontaneously fissionable nuclide from solutions with low salt background

International Nuclear Information System (INIS)

Korotkin, Yu.S.; Ter-Akop'yan, G.M.; Popeko, A.G.; Drobina, T.P.; Zhuravleva, E.L.

1982-01-01

The results of experiments on further concentration of a new natural spontaneously fissionable nuclide, the concentrates of which form the Cheleken geothermal brines have been obtained, are presented. The conclusions are drown about the chemical nature of a new spontaneously fissionable nuclide. It is a chalcophile element which copreipitates with sulphides of copper, lead, arsenic and mercury from weakly acid solutions. The behaviour of the new nuclide in sulphide systems in many respects is similar to the behaviour of polonium, astatine and probably of bismuth. The most probable stable valence of the new nuclide varies from +1 up to +3. The data available on the chemical behaviour of the new nuclide as well as the analysis over contamination by spontaneously fissionable isotopes permit to state that the new natural spontaneously fissionable nuclide does not relate to the known isotopes

Effect of prenatal exposure to different salt concentration on the third month's weight and blood pressure in wistar rat

International Nuclear Information System (INIS)

Fereidoun, H.

2009-01-01

In utero alterations in fluid and electrolyte endocrine systems may result in permanent effects on offspring. A low sodium intake during prenatal life jeopardizes growth in young rats, prenatal high-salt diet in Sprague-Dawley rats caused an increase in MAP at postnatal day 30. The objective of this study was to determine the effect of prenatal exposure to different salt concentrations on the third month's weight and blood pressure in Wistar rat. This study was performed at the Department of Physiology, Isfahan University of Medical Science, Isfahan, Iran, over a period from 1998 to 2003. Six groups of rat, 1 male and 5 female in each group were exposed to 0.5, 1, 1.4, 1.6, 1.8 and 2 percent of salt concentrations during pre-pregnancy, pregnancy and lactation period, another test group consumed distilled water and control group used Isfahan tap water, other living conditions for all groups were similar. Exposure to different salt concentrations on the third month's weight and blood pressure was evaluated. Prenatal exposure to 0.5 and 1% salt concentrations gives birth to more alive and healthy infants, and third month's weight increased significantly, but blood pressure was not influenced significantly. Salt concentrations higher than 1% increased the maternal and infant mortality rate and blood pressure significantly, but some concentrations decreased third month's weight significantly. Level of dietary salt during intrauterine development can influence on the number of alive and healthy infants, birth weight, third month' weight and blood pressure significantly. There is no need to introduce a salt restricted diet in prenatal care, a balanced diet in sodium during pregnancy is recommended, high salt diet creates harmful effect. (author)

Effects of salting treatment on the physicochemical properties, textural properties, and microstructures of duck eggs

Science.gov (United States)

Xu, Lilan; Zhao, Yan; Xu, Mingsheng; Yao, Yao; Nie, Xuliang; Du, Huaying

2017-01-01

In order to illuminate the forming process of salted egg, the effects of the brine solution with different salt concentrations on the physicochemical properties, textural properties, and microstructures of duck eggs were evaluated using conventional physicochemical property determination methods. The results showed that the moisture contents of both the raw and cooked egg whites and egg yolks, the springiness of the raw egg yolks and cooked egg whites exhibited a decreasing trend with the increase in the salting time and salt concentration. The salt content, oil exudation and the hardness of the raw egg yolks showed a constantly increasing trend. Viscosity of the raw egg whites showed an overall trend in which it first deceased and then increased and decreased again, which was similar to the trend of the hardness of the cooked egg whites and egg yolks. As the salting proceeded, the pH value of the raw and cooked egg whites declined remarkably and then declined slowly, whereas the pH of the raw and cooked egg yolks did not show any noticeable changes. The effect of salting on the pH value varied significantly with the salt concentration in the brine solution. Scanning electron microscopy (SEM) revealed that salted yolks consist of spherical granules and embedded flattened porosities. It was concluded that the treatment of salt induces solidification of yolk, accompanied with higher oil exudation and the development of a gritty texture. Different salt concentrations show certain differences. PMID:28797071

Water Uptake By Mars Salt Analogs: An Investigation Of Stable Aqueous Solutions On Mars Using Raman Microscopy

Science.gov (United States)

Nuding, D.; Gough, R. V.; Jorgensen, S. K.; Tolbert, M. A.

2013-12-01

To understand the formation of briny aqueous solutions on Mars, a salt analog was developed to closely match the individual cation and anion concentrations as reported by the Wet Chemistry Laboratory aboard the Phoenix Lander. ';Instant Mars' is a salt analog developed to fully encompass the correct concentrations of magnesium, calcium, potassium, sodium, perchlorate, chloride, and sulfate ions. Using environmental Raman microscopy, we have studied the water uptake by the Instant Mars analog as a function of temperature and relative humidity. Water uptake was monitored using Raman spectroscopy in combination with optical microscopy. A MicroJet droplet generator was used to generate 30 μm diameter particles that were deposited onto a quartz disc. The particles undergo visual transformations as the relative humidity (RH) is increased and the presence of water uptake is confirmed by Raman spectroscopy. At -30° C, water uptake begins at ~ 35% RH as humidity is increased. The water uptake is marked by the growth of a sulfate peak at 990 cm-1, an indicator that sulfate has undergone a phase transition into an aqueous state. As the RH continues to increase, the peak in the O-H region (~3500 cm-1) broadens as more liquid water accumulates in the particles. The Instant Mars particles achieve complete deliquescence at 68% RH, indicated both visually and with Raman spectroscopy. The gradual water uptake observed suggests that deliquescence of the Instant Mars particles is not an immediate process, but that it occurs in steps marked by the deliquescence of the individual salts. Perhaps of even more significance is the tendency for the Instant Mars particles to remain aqueous at low humidity as RH is decreased. Raman spectra indicate that liquid water is present as low as 2% RH at -30° C. Ongoing work will examine the phase of Instant Mars particles under simulated Martian surface and subsurface conditions to gain insight into the possibility for aqueous solutions on Mars

Contribution to the study of uranyl salts in butyl phosphate solutions

International Nuclear Information System (INIS)

Coulon, A.

1965-06-01

A spectroscopic study in the normal infrared region and involving the following associations: tri-alkyl phosphates (tri-butyl, tri-ethyl, tri-methyl), uranyl salts (nitrate, chloride, acetate) has confirmed the existence of an interaction between the phosphoryl group and the uranium atom, as shown by a movement of absorption band for the valency P = 0 from ∼ 1270 cm -1 to ∼ 1180 cm -1 . A study of the preparation, analysis and spectroscopy of the solids obtained by the precipitation of uranyl salts by acid butyl phosphates has been carried out. By infrared spectrophotometry it has been shown that the tri-butyl and di-butyl phosphates are associated in non-polar diluents even before the uranium is introduced. The extraction of uranyl salts from acid aqueous solutions by a diluted mixture of tri-butyl and di-butyl phosphates proceeds by different mechanisms according to the nature of the ion (nitrate or chloride). (author) [fr

Dynamic flow method to study the CO2 loading capacity of amino acid salt solutions

DEFF Research Database (Denmark)

Lerche, Benedicte Mai; Stenby, Erling Halfdan; Thomsen, Kaj

Due to a number of advantages amino acid salt solutions have emerged as alternatives to the alkanolamine solvents for the chemical absorption of CO2 from flue gas. The use of amino acids in CO2 capture is a bio-mimetic process, as it is similar to CO2 binding by proteins in the blood......, such as hemoglobin. Amino acid salt solutions have the same amine functionality as alkanolamines, and are thus expected to behave similar towards CO2 in flue gas. Despite rising interest, few studies have been performed so far on amino acids as CO2 absorbents....

The effect of growing media and concentration of nutrient solution on growth, flowering and macroelement content of media and leaves of Tymophylla tenuiloba Small

Directory of Open Access Journals (Sweden)

Joanna Nowak

2013-12-01

Full Text Available Effects of growing media and concentration of nutrient solution on growth, flowering, evapotranspiration and macroelement content of media and leaves of Tymophylla tenuiloba were evaluated under ebb-and-flow conditions. Two media: peat and peat + perlite (3:l, v/v, and four concentrations of nutrient solution: 1.0, 1.5, 2.0, 2.5 mS cm-1 were applied. High quality plants were produced in both media and all concentration of nutrient solution. The lowest evapotranspiration was measured at the highest concentration of nutrient solution. N concentration of leaves was high in all treatments. Concentrations of K, Ca, and Mg decreased with increasing concentration of nutrient solution. Opposite was found for P. At the end of cultivation the lowest pH was measured in the upper layer of growing media. The highest total soluble salt level was measured in the upper layers. Upper layers accumulated more N-NO3, P, Ca, and Mg. Mineral element content of both media was high in all concentrations of nutrient solution. Low concentration of nutrient solution at 1.0 mS cm-1 is recommended, although -1Tymophylla tenuiloba-1 can be also cultivated at higher concentrations of nutrient solution up to 2.5mS cm-1, if placed on the same bench with other bedding plants requiring more nutrients.

Potentiometric titration curves of aluminium salt solutions and its species conversion in the hydrolysis-polymerization course

Directory of Open Access Journals (Sweden)

Chenyi Wang

2008-12-01

Full Text Available A new concept of critical point is expounded by analysing the potentiometric titration curves of aluminium salt solutions under the moderate slow rate of base injection. The critical point is defined as the characteristic spot of the Al3+ salt solutions potentiometric titration curve, which is related to the experiment conditions. In addition, the changes of critical points reflect the influence of experiment conditions on the course of the hydrolysis-polymerization and the conversion of hydroxyl polynuclear aluminum species. According to the OH/Al mole ratio, the Al species can be divided into four regions quantitatively by three characteristic points on the titration curves: Part I, Al3+/Ala region, consist chiefly of Al3+ and mononuclear Al; Part II, the small/middle polynuclear Al region, including Al2-Al12; Part III, the large-size polynuclear aluminum region, consistent with predominantly Al13-Al54 and a little sol/gel Al(OH3; Part IV, the dissolving region of sol/gel Alc, only Al(OH 3 (aq or am and Al(OH4- species, which set up a base to study on the hydrolysis-polymerization of Al3+. At the same time, significant effects of total aluminum concentration, temperature, halide ion, silicate radical, and organic acid radical on the titration curves and its critical points were observed. Given the three critical points which demarcating the aluminum forms, we carry out a through investigation into the fundamental regulations of these factors’ influence, and offer a fresh train of thought to study the hydrolysis-polymerization of Al3+ in soil solutions.

Assessment of drug salt release from solutions, suspensions and in situ suspensions using a rotating dialysis cell

DEFF Research Database (Denmark)

Parshad, Henrik; Frydenvang, Karla; Liljefors, Tommy

2003-01-01

buffer is used as release media. Generally, the initial release of the drug salt from in situ suspensions occurred faster as compared to conventional suspensions, probably due to incomplete precipitation of the drug salt, and hence formation of supersaturated solutions where the rate of release......A rotating dialysis cell consisting of a small (10 ml) and a large compartment (1000 ml) was used to study the release of drug salt (bupivacaine 9-anthracene carboxylate) from (i). solutions, (ii). suspensions and (iii). in situ formed suspensions. Initial release experiments from suspensions...... indicated that the release of drug salt in deionized water was predominantly limited by the diffusion across the membrane whereas it is essentially dissolution rate controlled in 0.05 M phosphate buffer (pH 7.40). Thus, the in vitro model appears to have a potential in formulation screening when phosphate...

Chemical perspectives on alkali and earth alkaline nitrate and nitrite salts for concentrated solar power applications

Energy Technology Data Exchange (ETDEWEB)

Cordaro, Joseph G. [Sandia National Labsoratories, Livermore, CA (United States)

2013-04-01

Molten salts have been widely considered as the leading candidate heat transfer fluids (HTF) used in high temperature, concentrated solar power plants. Specifically, nitrate and nitrite based salts have been investigated as a HTF and even deployed in pilot plants generating up to 19.9 MW of electricity at operating temperatures above 500 C. New plant designs requiring higher operating temperatures for better efficiencies are pushing the stability limit of HTF. This paper presents an overview of the thermophysical properties of nitrate and nitrite salts and discusses thermodynamic and kinetic stability limitations as they relate to concentrated solar power generation. (orig.)

The salting-out effect and phase separation in aqueous solutions of tri-sodium citrate and 1-butyl-3-methylimidazolium bromide

Energy Technology Data Exchange (ETDEWEB)

Sadeghi, Rahmat, E-mail: rsadeghi@uok.ac.i [Department of Chemistry, University of Kurdistan, Sanandaj (Iran, Islamic Republic of); Golabiazar, Roonak [Department of Chemistry, University of Kurdistan, Sanandaj (Iran, Islamic Republic of); Shekaari, Hemayat [Department of Chemistry, Faculty of Science, University of Mohaghegh Ardabili, Ardabil (Iran, Islamic Republic of)

2010-04-15

The aim of this work is to obtain further evidence about the salting-out effect produced by the addition of tri-sodium citrate to aqueous solutions of water miscible ionic liquid 1-butyl-3-methylimidazolium bromide ([C{sub 4}mim][Br]) by evaluating the effect of tri-sodium citrate on the thermodynamic properties of aqueous solutions of this ionic liquid. Experimental measurements of density and sound velocity at different temperatures ranging from (288.15 to 308.15) K, the refractive index at 308.15 K and the liquid-liquid phase diagram at different temperatures ranging from (288.15 to 338.15) K for aqueous solutions containing 1-butyl-3-methylimidazolium bromide ([C{sub 4}mim][Br]) and tri-sodium citrate (Na{sub 3}Cit) are taken. The apparent molar volume of transfer of [C{sub 4}mim][Br] from water to aqueous solutions of Na{sub 3}Cit have positive values and it increases by increasing salt molality. Although at high IL molality, the apparent molar isentropic compressibility shows similar behaviour with that of the apparent molar volume. However at low concentrations of IL, the apparent molar isentropic compressibility of transfer of [C{sub 4}mim][Br] from water to aqueous solutions of Na{sub 3}Cit have negative values. The effects of temperature and the addition of Na{sub 3}Cit and [C{sub 4}mim][Br] on the liquid-liquid phase diagram of the investigated system have been studied. It was found that an increase in temperature caused the expansion of the one-phase region. The presence of Na{sub 3}Cit triggers a salting-out effect, leading to significant upward shifts of the liquid-liquid de-mixing temperatures of the system. The effect of temperature on the phase-forming ability in the system investigated has been studied based on a salting-out coefficient obtained from fitting the binodal values to a Setschenow-type equation for each temperature. Based on cloud point values, the energetics of the clouding process have been estimated and it was found that both of

Biaxial testing of canine annulus fibrosus tissue under changing salt concentrations

Directory of Open Access Journals (Sweden)

Jacques M. Huyghe

2010-03-01

Full Text Available The in vivo mechanics of the annulus fibrosus of the intervertebral disc is one of biaxial rather than uniaxial loading. The material properties of the annulus are intimately linked to the osmolarity in the tissue. This paper presents biaxial relaxation experiments of canine annulus fibrosus tissue under stepwise changes of external salt concentration. The force tracings show that stresses are strongly dependent on time, salt concentration and orientation. The force tracing signature of are sponse to a change instrain, is one of a jumpin stress that relaxes partly as the new strain is maintained. The force tracing signature of a stepwise change in salt concentration is a progressive monotonous change in stress towards a new equilibrium value. Although the number of samples does not allow any definitive quantitative conclusions, the trends may shed light on the complex interaction among the directionality of forces, strains and fiber orientation on one hand, and on the other hand, the osmolarity of the tissue. The dual response to a change in strain is understood as an immediate response before fluid flows in or out of the tissue, followed by a progressive readjustment of the fluid content in time because of the gradient in fluid chemical potential between the tissue and the surrounding solution.A mecânica in vivo do anel fibroso do disco intervertebral é baseada em carregamento biaxial ao invés de uniaxial. As propriedades materiais do anel estão intimamente ligadas à osmolaridade no tecido. O artigo apresenta experimentos de relaxação biaxiais do anel fibroso de um tecido canino sob mudanças abruptas na concentração externa de sal. A assinatura da força devido à mudança brusca de salinidade resulta em uma progressiva e monótona mudança na tensão em direção a um novo valor de equilíbrio. Embora o número de amostras não permita nenhuma conclusão quantitativa, as tendências podem abrir uma luz no entendimento das intera

Lowering of the critical concentration for micelle formation in aqueous soap solutions by action of truly dissolved hydrocarbon at various temperatures

Energy Technology Data Exchange (ETDEWEB)

Markina, Z.N.; Kostova, N.Z.; Rebinder, P.A.

1970-03-01

The effect of dissolved hydrocarbons (octane, benzene, and ethylbenzene) on critical micelle concentration of aqueous solutions of sodium salts of fatty acids from caproate to sodium myristate at various temperatures was studied. Experimental results showed that formation of micelles is promoted by presence of hydrocarbons dissolved in the water phase. Such solutions have below normal critical micelle concentration. The change in critical micelle concentration decreases with increase in length of hydrocarbon chain in the soap molecule and with decrease of hydrocarbon solubility in pure water. The nature of the hydrocarbon also affects the forms and dimension of the micelle. Aromatic hydrocarbons increase micelle volume and greatly decrease C.M.C., while aliphatic hydrocarbons decrease C.M.C. slightly. (12 refs.)

Magnesium degradation influenced by buffering salts in concentrations typical of in vitro and in vivo models

Energy Technology Data Exchange (ETDEWEB)

Agha, Nezha Ahmad; Feyerabend, Frank [Helmholtz-Zentrum Geesthacht, Institute of Material Research, Division of Metallic Biomaterials, Max-Planck-Str. 1, 21502 Geesthacht (Germany); Mihailova, Boriana; Heidrich, Stefanie; Bismayer, Ulrich [University of Hamburg, Department of Earth Sciences, Grindelallee 48, 20146 Hamburg (Germany); Willumeit-Römer, Regine [Helmholtz-Zentrum Geesthacht, Institute of Material Research, Division of Metallic Biomaterials, Max-Planck-Str. 1, 21502 Geesthacht (Germany)

2016-01-01

Magnesium and its alloys have considerable potential for orthopedic applications. During the degradation process the interface between material and tissue is continuously changing. Moreover, too fast or uncontrolled degradation is detrimental for the outcome in vivo. Therefore in vitro setups utilizing physiological conditions are promising for the material/degradation analysis prior to animal experiments. The aim of this study is to elucidate the influence of inorganic salts contributing to the blood buffering capacity on degradation. Extruded pure magnesium samples were immersed under cell culture conditions for 3 and 10 days. Hank's balanced salt solution without calcium and magnesium (HBSS) plus 10% of fetal bovine serum (FBS) was used as the basic immersion medium. Additionally, different inorganic salts were added with respect to concentration in Dulbecco's modified Eagle's medium (DMEM, in vitro model) and human plasma (in vivo model) to form 12 different immersion media. Influences on the surrounding environment were observed by measuring pH and osmolality. The degradation interface was analyzed by electron-induced X-ray emission (EIXE) spectroscopy, including chemical-element mappings and electron microprobe analysis, as well as Fourier transform infrared reflection micro-spectroscopy (FTIR). - Highlights: • Influence of blood buffering salts on magnesium degradation was studied. • CaCl{sub 2} reduced the degradation rate by Ca–PO{sub 4} layer formation. • MgSO{sub 4} influenced the morphology of the degradation interface. • NaHCO{sub 3} induced the formation of MgCO{sub 3} as a degradation product.

Radionuclide concentrations in salt pans in the coastal area of Cox's Bazar, Bangladesh

International Nuclear Information System (INIS)

Alam, M.N.; Chowdhury, M.I.; Zafar, M.; Kamal, M.; Ghose, S.; Kamal, A.H.M.

1998-01-01

Radionuclide concentrations of 226 Ra, 232 Th, 137 Cs, 134 Cs and 40 K in samples of water, soil and salt from three gradients of salt pans (reservoir, condenser and crystalliser) in the coastal area of Cox's Bazar, Bangladesh and in samples of refined salts were measured using γ-spectrometry. The activities of 226 Ra in the salt pans were found to be in the range 3·18±1·02 Bq l -1 in water to 25·17±5·76 Bq kg -1 in soil; 232 Th activities were 2·01±0·89 Bq l -1 in water to 42·33±2·54 Bq kg -1 in soil, and 40 K activities ranged from 109·60±27·77 Bq l -1 in water to 651·89±65·89 Bq kg -1 in soil. No 137 Cs or 134 Cs was found in soil, salt and water from the salt pans investigated. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

Self-assembly of micelles in organic solutions of lecithin and bile salt: Mesoscale computer simulation

Science.gov (United States)

Markina, A.; Ivanov, V.; Komarov, P.; Khokhlov, A.; Tung, S.-H.

2016-11-01

We propose a coarse-grained model for studying the effects of adding bile salt to lecithin organosols by means of computer simulation. This model allows us to reveal the mechanisms of experimentally observed increasing of viscosity upon increasing the bile salt concentration. We show that increasing the bile salt to lecithin molar ratio induces the growth of elongated micelles of ellipsoidal and cylindrical shape due to incorporation of disklike bile salt molecules. These wormlike micelles can entangle into transient network displaying perceptible viscoelastic properties.

Physicochemical investigations on the extraction mechanism of some elements and inorganic acids by quaternary ammonium salts

International Nuclear Information System (INIS)

Szeglowski, Z.

1974-01-01

The extraction of rare earth and transplutonium elements, Tl, Pb, Bi, and Po, and also of HNO 3 and HCl, with chloroform solutions of cetylpyridinium salts solutions showed that the salts aggregate in chloroform solutions, forming micelles above a concentration of about 10 -2 M. Surface tension and surface potential measurements proved that cetylpyridinium nitrate is not transferred to HNO 3 solutions in the extraction system, while cetylpyridinium chloride is transferred to ECl solutions. (author)

The potential/pH diagram of silver in aqueous ammonium salt solution

NARCIS (Netherlands)

Sluyters, J.H.; Wijnen, M.D.; Hul, H.J. van den

1961-01-01

The potential/pH diagram of silver in aqueous ammonium salt solution at 25°C has been calculated and verified experimentally. Calculations were carried out on the basis of the standard potential of the silver/silver-ion couple, the dissociation constants of the silver mono- and di-ammonia

Structure and thermodynamics of nonideal solutions of colloidal particles. Investigation of salt-free solutions of human serum albumin by using small-angle neutron scattering and Monte Carlo simulation

DEFF Research Database (Denmark)

Sjøberg, B.; Mortensen, K.

1997-01-01

Carlo simulation, to study salt-free solutions of human serum albumin (HSA) in the concentration range up to 0.26 g ml(-1). The model calculations of the theoretical SANS intensities are quite general, thus avoiding the approximation that the relative positions and orientations of the particles......-shaped potential which is spherically oriented around the particles. The combination of SANS and statistical thermodynamics also allows a determination of the nonideal part of the chemical potential and the activity coefficient of HSA. As expected the activity coefficient deviates strongly from the value one...

DC electrophoresis and viscosity of realistic salt-free concentrated suspensions: non-equilibrium dissociation-association processes.

Science.gov (United States)

Ruiz-Reina, Emilio; Carrique, Félix; Lechuga, Luis

2014-03-01

Most of the suspensions usually found in industrial applications are concentrated, aqueous and in contact with the atmospheric CO2. The case of suspensions with a high concentration of added salt is relatively well understood and has been considered in many studies. In this work we are concerned with the case of concentrated suspensions that have no ions different than: (1) those stemming from the charged colloidal particles (the added counterions, that counterbalance their surface charge); (2) the H(+) and OH(-) ions from water dissociation, and (3) the ions generated by the atmospheric CO2 contamination. We call this kind of systems "realistic salt-free suspensions". We show some theoretical results about the electrophoretic mobility of a colloidal particle and the electroviscous effect of realistic salt-free concentrated suspensions. The theoretical framework is based on a cell model that accounts for particle-particle interactions in concentrated suspensions, which has been successfully applied to many different phenomena in concentrated suspensions. On the other hand, the water dissociation and CO2 contamination can be described following two different levels of approximation: (a) by local equilibrium mass-action equations, because it is supposed that the reactions are so fast that chemical equilibrium is attained everywhere in the suspension, or (b) by non-equilibrium dissociation-association kinetic equations, because it is considered that some reactions are not rapid enough to ensure local chemical equilibrium. Both approaches give rise to different results in the range from dilute to semidilute suspensions, causing possible discrepancies when comparing standard theories and experiments concerning transport properties of realistic salt-free suspensions. Copyright © 2013 Elsevier Inc. All rights reserved.

Coagulation mechanism of salt solution-extracted active component in Moringa oleifera seeds

OpenAIRE

Okuda, Tetsuji; Baes, Aloysius U.; Nishijima, Wataru; Okada, Mitsumasa

2001-01-01

This study focuses on the coagulation mechanism by the purified coagulant solution (MOC-SC-PC) with the coagulation active component extracted from M. oleifera seeds using salt solution. The addition of MOC-SC-PC into tap water formed insoluble matters. The formation was responsible for kaolin coagulation. On the other hand, insoluble matters were not formed when the MOC-SC-PC was added into distilled water. The formation was affected by Ca2+ or other bivalent cations which may connect each m...

Criticality considerations for salt-cake disolution in DOE waste tanks

International Nuclear Information System (INIS)

Trumble, E.F.; Niemer, K.A.

1995-01-01

A large amount of high-level waste is being stored in the form of salt cake at the Savannah River site (SRS) in large (1.3 x 106 gal) underground tanks awaiting startup of the Defense Waste Processing Facility (DWPF). This salt cake will be dissolved with water, and the solution will be fed to DWPF for immobilization in borosilicate glass. Some of the waste that was transferred to the tanks contained enriched uranium and plutonium from chemical reprocessing streams. As water is added to these tanks to dissolve the salt cake, the insoluble portion of this fissile material will be left behind in the tank as the salt solution is pumped out. Because the salt acts as a diluent to the fissile material, the process of repeated water addition, salt dissolution, and salt solution removal will act as a concentrating mechanism for the undissolved fissile material that will remain in the tank. It is estimated that tank 41 H at SRS contains 20 to 120 kg of enriched uranium, varying from 10 to 70% 235 U, distributed nonuniformly throughout the tank. This paper discusses the criticality concerns associated with the dissolution of salt cake in this tank. These concerns are also applicable to other salt cake waste tanks that contain significant quantities of enriched uranium and/or plutonium

IMPACTS OF ROAD DE-ICING SALTS ON MANGANESE TRANSPORT TO GROUNDWATER IN ROADSIDE SOILS

OpenAIRE

Wen, Yingrong

2012-01-01

Manganese (Mn) is an important element in soil, it occur natural in minerals and precipitated as Mn-oxides. Several factors could decide the solubility and mobility of Mn in soil water. In this study, the impact of road de-icing salts (NaCl) on manganese mobilization and transport to groundwater in roadside soils has been investigated by leaching tests. Generally, in the salt solution leachates, the water-soluble concentrations of Mn tended to increase with elevated salt concentrations, sugge...

Solution-derived sodalite made with Si- and Ge-ethoxide precursors for immobilizing electrorefiner salt

Energy Technology Data Exchange (ETDEWEB)

Riley, Brian J., E-mail: brian.riley@pnnl.gov; Lepry, William C.; Crum, Jarrod V.

2016-01-15

Chlorosodalite has the general form of Na{sub 8}(AlSiO{sub 4}){sub 6}Cl{sub 2} and this paper describes experiments conducted to synthesize sodalite with a solution-based approach to immobilize a simulated spent electrorefiner salt solution containing a mixture of alkali, alkaline earth, and lanthanide chlorides. The reactants used were the salt solution, NaAlO{sub 2}, and either Si(OC{sub 2}H{sub 5}){sub 4} or Ge(OC{sub 2}H{sub 5}){sub 4}. Additionally, seven different glass sintering aids (at loadings of 5 mass%) were evaluated as sintering aids for consolidating the as-made powders using a cold-press-and-sinter technique. This process of using alkoxide additives for the Group IV component can be used to produce large quantities of sodalite at near-room temperature as compared to a method where colloidal silica was used as the silica source. However, the small particle sizes inhibited densification during heat treatments.

Molecular dynamics study of charged dendrimers in salt-free solution : effect of counterions

NARCIS (Netherlands)

Gurtovenko, A.A.; Lyulin, S.V.; Karttunen, M.E.J.; Vattulainen, I.

2006-01-01

Polyamidoamine dendrimers, being protonated under physiological conditions, represent a promising class of nonviral, nanosized vectors for drug and gene delivery. We performed extensive molecular dynamics simulations of a generic model dendrimer in a salt-free solution with dendrimer’s terminal

Hydrogen Generation in Microbial Reverse-Electrodialysis Electrolysis Cells Using a Heat-Regenerated Salt Solution

KAUST Repository

Nam, Joo-Youn

2012-05-01

Hydrogen gas can be electrochemically produced in microbial reverse-electrodialysis electrolysis cells (MRECs) using current derived from organic matter and salinity-gradient energy such as river water and seawater solutions. Here, it is shown that ammonium bicarbonate salts, which can be regenerated using low-temperature waste heat, can also produce sufficient voltage for hydrogen gas generation in an MREC. The maximum hydrogen production rate was 1.6 m3 H2/m3·d, with a hydrogen yield of 3.4 mol H2/mol acetate at a salinity ratio of infinite. Energy recovery was 10% based on total energy applied with an energy efficiency of 22% based on the consumed energy in the reactor. The cathode overpotential was dependent on the catholyte (sodium bicarbonate) concentration, but not the salinity ratio, indicating high catholyte conductivity was essential for maximizing hydrogen production rates. The direction of the HC and LC flows (co- or counter-current) did not affect performance in terms of hydrogen gas volume, production rates, or stack voltages. These results show that the MREC can be successfully operated using ammonium bicarbonate salts that can be regenerated using conventional distillation technologies and waste heat making the MREC a useful method for hydrogen gas production from wastes. © 2012 American Chemical Society.

Modeling Episodic Ephemeral Brine Lake Evaporation and Salt Crystallization on the Bonneville Salt Flats, Utah

Science.gov (United States)

Liu, T.; Harman, C. J.; Kipnis, E. L.; Bowen, B. B.

2017-12-01

Public concern about apparent reductions in the areal extent of the Bonneville Salt Flat (BSF) and perceived changes in inundation frequency has motivated renewed interest in the hydrologic and geochemical behavior of this salt playa. In this study, we develop a numerical modeling framework to simulate the relationship between hydrometeorologic variability, brine evaporation and salt crystallization processes on BSF. The BSF, locates in Utah, is the remnant of paleo-lake Bonneville, and is capped by up to 1 meter of salt deposition over a 100 km2 area. The BSF has two distinct hydrologic periods each year: a winter wet periods with standing surface brine and the summer dry periods when the brine is evaporated, exposing the surface salt crust. We develop a lumped non-linear dynamical models coupling conservation expressions from water, dissolved salt and thermal energy to investigate the seasonal and diurnal behavior of brine during the transition from standing brine to exposed salt at BSF. The lumped dynamic models capture important nonlinear and kinetic effects introduced by the high ionic concentration of the brine, including the pronounced effect of the depressed water activity coefficient on evaporation. The salt crystallization and dissolution rate is modeled as a kinetic process linearly proportional to the degree of supersaturation of brine. The model generates predictions of the brine temperature and the solute and solvent masses controlled by diurnal net radiation input and aerodynamic forcing. Two distinct mechanisms emerge as potential controls on salt production and dissolution: (1) evapo-concentration and (2) changes in solubility related to changes in brine temperature. Although the evaporation of water is responsible for ultimate disappearance of the brine each season ,variation in solubility is found to be the dominant control on diurnal cycles of salt precipitation and dissolution in the BSF case. Most salt is crystallized during nighttime, but the

Enhanced ethanol production by fermentation of Gelidium amansii hydrolysate using a detoxification process and yeasts acclimated to high-salt concentration.

Science.gov (United States)

Ra, Chae Hun; Jung, Jang Hyun; Sunwoo, In Yung; Jeong, Gwi-Taek; Kim, Sung-Koo

2015-06-01

A total monosaccharide concentration of 59.0 g/L, representing 80.1 % conversion of 73.6 g/L total fermentable sugars from 160 g dw/L G. amansii slurry was obtained by thermal acid hydrolysis and enzymatic hydrolysis. Subsequent adsorption treatment using 5 % activated carbon with an adsorption time of 2 min was used to prevent the inhibitory effect of 5-hydroxymethylfurfural (HMF) >5 g/L in the medium. Ethanol production decreased with increasing salt concentration using C. tropicalis KCTC 7212 non-acclimated or acclimated to a high concentration of salt. Salt concentration of 90 psu was the maximum concentration for cell growth and ethanol production. The levels of ethanol production by C. tropicalis non-acclimated or acclimated to 90 psu high-salt concentration were 13.8 g/L with a yield (YEtOH) of 0.23, and 26.7 g/L with YEtOH of 0.45, respectively.

Anodic behavior of stainless-steel substrate in organic electrolyte solutions containing different lithium salts

International Nuclear Information System (INIS)

Furukawa, Kazuki; Yoshimoto, Nobuko; Egashira, Minato; Morita, Masayuki

2014-01-01

Highlights: • We investigated anodic behavior of stainless-steel in organic electrolytes for advanced capacitor. • Anion of the electrolyte affected the anodic stability of the alloy. • Anodic passivation occurs in LiPF 6 solution but pitting or active dissolution proceeds in other electrolyte solutions. • Fluoride source in the solution contributes to forming a stable surface layer on the stainless steel. - Abstract: The anodic behavior of austenitic stainless-steel, SUS304, as a current collector of positive electrode in lithium-ion battery/capacitor has been investigated in organic electrolyte solutions based on a mixed alkyl carbonate solvent with different lithium salts. Stable passivation characteristics were observed for the stainless-steel in the LiPF 6 solution, but pitting corrosion or active dissolution proceeded in the solutions containing other anions, BF 4 - , (CF 3 SO 2 ) 2 N - (TFSA - ) and ClO 4 - . The mass ratios of the dissolved metal species in the solutions of LiTFSA and LiClO 4 were equivalent to that of the alloy composition, which suggests that no preferential dissolution occurs during the anodic polarization in these electrolyte solutions. An HF component formed by decomposition of PF 6 - with the contaminate water will act as an F - source for the formation of a surface fluoride layer, that will contribute to the anodic stability of SUS304 in the LiPF 6 solution. The anodic corrosion in the LiTFSA solution was suppressed in part by mixing the PF 6 salt or adding HF in the electrolyte

Doping Polymer Semiconductors by Organic Salts: Toward High-Performance Solution-Processed Organic Field-Effect Transistors.

Science.gov (United States)

Hu, Yuanyuan; Rengert, Zachary D; McDowell, Caitlin; Ford, Michael J; Wang, Ming; Karki, Akchheta; Lill, Alexander T; Bazan, Guillermo C; Nguyen, Thuc-Quyen

2018-04-24

Solution-processed organic field-effect transistors (OFETs) were fabricated with the addition of an organic salt, trityl tetrakis(pentafluorophenyl)borate (TrTPFB), into thin films of donor-acceptor copolymer semiconductors. The performance of OFETs is significantly enhanced after the organic salt is incorporated. TrTPFB is confirmed to p-dope the organic semiconductors used in this study, and the doping efficiency as well as doping physics was investigated. In addition, systematic electrical and structural characterizations reveal how the doping enhances the performance of OFETs. Furthermore, it is shown that this organic salt doping method is feasible for both p- and n-doping by using different organic salts and, thus, can be utilized to achieve high-performance OFETs and organic complementary circuits.

Salt Induced Decay of Masonry and Electrokinetic Repair

DEFF Research Database (Denmark)

Ottosen, Lisbeth M.; Rörig-Dalgaard, Inge

in brick depending on its water content and salts may be precipitated on the outer wall or concentrated under paint layers covering the surface of the brick. Different types of damage may appear in masonry walls due to these concentrating phenomena. Bricks themselves can be destroyed and the mortar can...... of bricks without increased salt content is very low compared to soils in general. Furthermore in a masonry wall there are boundaries with different chemistry (e.g. pH) that the ions must pass, brick-mortar boundaries. From initial experiments with electrokinetic removal of Ca2+ ions from bricks good......Salt induced decay of bricks is caused when salts exert internal pressures, which exceed the strength of the stone. The presence of aqueous electrolyte solutions in the capillary pores of brick materials can under changing climate conditions cause deterioration of wall structures. Ions move...

Precipitation of sparingly soluble salts in packed sandbeds

Science.gov (United States)

Pavlakou, Efstathia I.; Sygouni, Varvara; Paraskeva, Christakis A.

2015-04-01

One of the main problems encountered by the oil extraction industry, is the reduction of the local permeability of the rock formation near the extraction wells because of salt deposition in the pores of the rocks during the injection of brine water to displace the trapped oil ganglia within the oil formations. This phenomenon makes the oil recovery less efficient and under extreme cases the well is abandoned with a large amount of oil entrapped. Several detailed studies have been conducted in the past concerning sand bed consolidation using sparingly soluble salts for varying conditions (e.g. temperature, grain size, sand type, salt concentrations etc) and various salts [1]. Nevertheless, salt precipitation in the rock formation pores under the presence of other miscible or immiscible substances with water has not been investigated in details yet. In the present study, salt (CaCO3) precipitation experiments were performed in small beds packed with sea sand mixed with a low amount of CaCO3 seed grains. The experiments were performed using pure solutions (NaHCO3, CaCl2.2H2O) and solutions mixed with Ethylene Glycol in sand beds. Additionally, precipitation experiments were performed using pure solutions in sand beds saturated with oil phase (n-dodecane) for a wide range of solution supersaturation. During the experiments the ionic strength was kept constant. pH and concentration values of calcium ion of the effluent were measured and the precipitated salt crystals were identified using X-ray Diffraction (XRD) method. At the end of each experiment Scanning Electron Microscope (SEM) was conducted using a sample of the precipitated sand to identify the morphology of the precipitated crystals and their cohesion with sand grains. Acknowledgments This research was partially funded by the European Union (European Social Fund-ESF) and Greek National Funds through the Operational program "Education and Lifelong Learning" under the action Aristeia II (Code No 4420). References

Radiation-induced reduction of ditetrazolium salt in aqueous solutions

International Nuclear Information System (INIS)

Sadeghi, Ali; Chaychian, Mahnaz; Al-Sheikhly, Mohamad; McLaughlin, W.L.

2002-01-01

Color formation in aqueous solutions of the ditetrazolium salt blue tetrazolium (BT 2+ ) in the absence or presence of oxygen is a complex radiation chemical reaction. The final stable product is the poorly soluble diformazan violet to blue pigment having a broad spectral absorption band (λ max =552 nm). The reaction of BT 2+ with the hydrated electron proceeds by rapid reduction of BT 2+ followed by protonation at the nitrogen closest to the unsubstituted phenyl group, via the two intermediate tetrazolinyl radicals shared by the ditetrazole ring nitrogens. The effect of solution pH, N 2 O saturation, and the presence of the reducing agent dextrose are examined. The system serves as a radiochromic sensor and a dosimeter of ionizing radiations. Solutions of 5 mmol l -1 BT 2+ at pH 7.3 serve as dosimeters over an absorbed-dose range of approximately 0.2-6 kGy (dearated, with a range of 1-8 mmol l -1 dextrose) and of about 1-15 kGy (aerated, with 0.1 mol l -1 sodium formate and 5 mmol l -1 dextrose)

Use of alkali metal salts to prepare high purity single-walled carbon nanotube solutions and thin films

Science.gov (United States)

Ashour, Rakan F.

Single-walled carbon nanotubes (SWCNTs) display interesting electronic and optical properties desired for many advanced thin film applications, such as transparent conductive electrodes or thin-film transistors. Large-scale production of SWCNTs generally results in polydispersed mixtures of nanotube structures. Since SWCNT electronic character (conducting or semiconducting nature) depends on the nanotube structure, application performance is being held back by this inability to discretely control SWCNT synthesis. Although a number of post-production techniques are able to separate SWCNTs based on electronic character, diameter, or chirality, most still suffer from the disadvantage of high costs of materials, equipment, or labor intensity to be relevant for large-scale production. On the other hand, chromatographic separation has emerged as a method that is compatible with large scale separation of metallic and semiconducting SWCNTs. In this work, SWCNTs, in an aqueous surfactant suspension of sodium dodecyl sulfate (SDS), are separated by their electronic character using a gel chromatography process. Metallic SWCNTs (m-SWCNTs) are collected as initial fractions since they show minimum interaction with the gel medium, whereas, semiconducting SWCNTs (sc- SWCNTs) remain adsorbed to the gel. The process of sc-SWCNT retention in the gel is found to be driven by the packing density of SDS around the SWCNTs. Through a series of separation experiments, it is shown that sc-SWCNTs can be eluted from the gel simply by disturbing the configuration of the SDS/SWCNT micellar structure. This is achieved by either introducing a solution containing a co-surfactant, such as sodium cholate (SC), or solutions of alkali metal ionic salts. Analysis of SWCNT suspensions by optical absorption provides insights into the effect of changing the metal ion (M+ = Li+, Na+, and K+) in the eluting solution. Salts with smaller metal ions (e.g. Li+) require higher concentrations to achieve

Fermentation and microflora of plaa-som, a Thai fermented fish product prepared with different salt concentrations

DEFF Research Database (Denmark)

Paludan-Müller, Christine; Madsen, M.; Sophanodora, P.

2002-01-01

% salt (w/w) as well as two high-salt batches, containing 9% and 11% salt. pH decreased rapidly from 6 to 4.5 in low-salt batches, whereas in high-salt batches, a slow or no decrease in pH was found. Lactic acid bacteria (LAB) and yeasts were isolated as the dominant microorganisms during fermentation....... LAB counts increased to 108-109 cfu g-1 and yeast counts to 107-5 x 107 cfu g-1 in all batches, except in the 11% salt batch, where counts were 1-2 log lower. Phenotypic tests, ITS-PCR, carbohydrate fermentations and 16S rRNA gene sequencing identified LAB isolates as Pediococcus pentosaceus......Plaa-som is a Thai fermented fish product prepared from snakehead fish, salt, palm syrup and sometimes roasted rice. We studied the effects of different salt concentrations on decrease in pH and on microflora composition during fermentation. Two low-salt batches were prepared, containing 6% and 7...

On salting in effect of the second group metal rhodanides on aqueous-amine solutions

International Nuclear Information System (INIS)

Krupatkin, I.L.; Ostrovskaya, E.M.; Vorob'eva, L.D.; Kamyshnikova, G.V.

1978-01-01

The ''salting in'' effect of rhodanides of Group 2 metals (magnesium, calcium, strontium, barium) on aqueous-amine solutions (water-aniline, and water-o-toluidine systems) is studied. The solubility in these systems has been determined by the isothermal method at 25 deg C. Compositions of the co-existing liquid phases have been determined by refractometry. The phase diagrams of water-aniline-rhodanide of magnesium, calcium and strontium systems have the same qualitative view. These rhodanides ''salt in'' the water-aniline system so strongly that the systems are completely homogenized. According to the decreasing homogenization effect on the water-aniline and water-o-toluidine systems the salts may be arranged into the following series Mg(NCS) 2 >Ca(NCS) 2 >Sr(NCS) 2 >Ba(NCS) 2 . The ''salting in'. effect is weaker in the water-o-toluidine system rather than in the water-aniline one

Crystallization of inorganic salts from aqueous solutions in a microwave field

International Nuclear Information System (INIS)

Kochetkov, S. E.; Kuznetsov, V. A.; Lyashenko, A. V.; Bakshutov, V. S.

2006-01-01

The crystallization of some inorganic salts (KH 2 PO 4 , NaCl, Sr(NO 3 ) 2 , KNO 2 , Ca(OH) 2 ) by the thermal-gradient (with decreasing temperature) and solvent-evaporation methods using microwave heating of solutions is investigated. It is established that the growth rates of single crystals in a microwave field are an order of magnitude higher than obtained in other known techniques at comparable crystallization temperatures and supersaturations. For example, the growth rate of prismatic faces {100} of KH 2 PO 4 crystals is as high as 11 mm/day at supersaturations of ∼1.2%. The results obtained are discussed in the context of the effect of microwave radiation on the adsorption surface layers of crystals. Fine-grained phases of the salts under study are obtained by evaporation of the solvent

Convective heat transfer characteristics in the turbulent region of molten salt in concentric tube

International Nuclear Information System (INIS)

Chen, Y.S.; Wang, Y.; Zhang, J.H.; Yuan, X.F.; Tian, J.; Tang, Z.F.; Zhu, H.H.; Fu, Y.; Wang, N.X.

2016-01-01

In order to better understand the heat transfer behavior and characteristics of molten salt in heat exchanger, the convective heat transfer characteristics of molten salt in salt-to-oil concentric tube are studied. Overall heat transfer coefficients of the heat exchanger are calculated using Wilson plots. Heat transfer coefficients of tube side molten salt with the range of Reynolds number from 10,000 to 50,000 and the Prandtl number from 11 to 27 are evaluated invoking the calculated overall heat transfer coefficients. The effects of velocity and temperature on the convective heat transfer in the turbulent region of molten salt are studied by comparing with the traditional correlations. The results show that the heat transfer characteristics of molten salt are in line with the empirical heat transfer correlation; however, Dittus–Boelter, Gnielinski, Sieder–Tate and Hausen correlations all give a larger deviation for the experimental data. Finally, based on the experimental data and Sieder–Tate correlation, a modified heat transfer correlation is proposed and good agreement is observed between the experimental data and the modified correlation. The results will also provide an important reference for the design of the heat exchangers in the Thorium-based Molten Salt Reactor.

Effect of protein solution components in the adsorption of Herbaspirillum seropedicae GlnB protein on mica.

Science.gov (United States)

Ferreira, Cecília F G; Benelli, Elaine M; Klein, Jorge J; Schreiner, Wido; Camargo, Paulo C

2009-10-15

The adsorption of proteins and its buffer solution on mica surfaces was investigated by atomic force microscopy (AFM). Different salt concentration of the Herbaspirillum seropedicae GlnB protein (GlnB-Hs) solution deposited on mica was investigated. This protein is a globular, soluble homotrimer (36kDa), member of PII-like proteins family involved in signal transducing in prokaryote. Supramolecular structures were formed when this protein was deposited onto bare mica surface. The topographic AFM images of the GlnB-Hs films showed that at high salt concentration the supramolecular structures are spherical-like, instead of the typical doughnut-like shape for low salt concentration. AFM images of NaCl and Tris from the buffer solution showed structures with the same pattern as those observed for high salt protein solution, misleading the image interpretation. XPS experiments showed that GlnB protein film covers the mica surface without chemical reaction.

Effect of Heat Treatment and Salt Concentration on Free Amino Acids Composition of Sudanese Braided (Muddaffara Cheese during Storage

Directory of Open Access Journals (Sweden)

Mohamed O. E. Altahir

2014-07-01

Full Text Available The aim of this study was to assess the effect of heat treatment and salt concentrations (0, 5, and 10% on the free amino acids (FAA composition of Sudanese braided cheese (BC ripened for up to 3 months at 5±2°C. Heat and salt concentration significantly affected the FAA of braided cheese. The free amino acids concentrations of BC ripened in 0%, 5%, and 10% salted whey (SW were significantly fluctuated. Under ripening conditions tested (salt level + time, braided cheese made from pasteurized milk (BCPM had consistently lower values of FAA than braided cheese made from raw milk (BCRM. In fresh cheese, the major FAA in BCRM were Glu (36.12 nmol/ml, Leu (26.77nmol/ml and Lys (14.51 nmol/ml while the major ones in BCPM were Lys (2.94 nmol/ml and Ala (2.45 nmol/ml. BCPM stored in 10% SW had shorter quality life compared to that stored in 5% salted whey.

Study of the influence of pre-activation of vermiculite and concentration of the quaternary ammonium salt in obtaining of organovermiculita

International Nuclear Information System (INIS)

Silva, A.L.; Barboza, E.A.; Souza, F.K.A.; Neves, G.A.; Santana, L.N.L.

2011-01-01

Organoclays, are derived from the addition of quaternary ammonium salts in aqueous dispersions of natural clays or sodium. The aim of this study was to obtain organoclays from the intercalation of clay mineral vermiculite and quaternary ammonium salt Praepagem WB, thus, was used to study the concentrations of salt activation of Na 2 CO 3 , the cure time of this salt and varying the concentration the quaternary ammonium salt. The X-ray diffraction was used to determine whether there was a change in basal spacing after intercalation process with the quaternary ammonium salt. The process of organophilization of vermiculite, was confirmed by change in clay basal interplanar distance, which was 14.32 Å and after the addition of salt increased to 60.04 Å when activated for 5 days. (author)

Salt concentrations during water production resulting from CO₂ storage

DEFF Research Database (Denmark)

Walter, Lena; Class, Holger; Binning, Philip John

2014-01-01

present in the saline aquifer. The brine can be displaced over large areas and can reach shallower groundwater resources. High salt concentrations could lead to a degradation of groundwater quality. For water suppliers the most important information is whether and how much salt is produced at a water...... displacement and infiltration could result in hazards for human health and the environment and therefore have to be investigated in detail. In this work numerical simulations are performed to estimate the risk related to the displacement of brine. The injected CO2 will displace the brine that is initially...

Effect of plant-derived smoke solutions on physiological and biochemical attributes of maize (Zea mays L.) under salt stress

International Nuclear Information System (INIS)

Waheed, M.A.; Shakir, S.K.; Rehman, S.U.; Khan, M.D.

2016-01-01

Among abiotic stresses, salinity is an important factor reducing crop yield. Plant-derived smoke solutions have been used as growth promoters since last two decades. The present study was conducted to investigate the effect of Cymbopogon jwaracusa smoke extracts (1:100 and 1:400) on physiological and biochemical aspects of maize (Zea mays L.) under salt stress (100, 150, 200 and 250 mM). Results showed that seed germination percentage was improved up to 93% with smoke as compared to control (70%), while seedling vigor in term of root and shoot fresh weights and dry weights were also significantly increased in seeds primed with smoke extracts. Similarly, in case of alleviating solutions, there occurred a significant alleviation in the adverse effects of salt solutions when mixed smoke in all studied end points. Application of smoke solution has also increased the level of K+ and Ca+2 while reduced the level of Na+ content in maize. In addition, the levels of photosynthetic pigments, total nitrogen and protein contents were also alleviated with the application of smoke as compared to salt. There occurred an increase in the activities of Anti-oxidant in response of salt stress but overcome with the smoke application. It can be concluded that plant-derived smoke solution has the potential to alleviate the phytotoxic effects of saline condition and can increased the productivity in plants. (author)

A Liquid Inorganic Electrolyte Showing an Unusually High Lithium Ion Transference Number: A Concentrated Solution of LiAlCl4 in Sulfur Dioxide

Directory of Open Access Journals (Sweden)

Martin Winter

2013-08-01

Full Text Available We report on studies of an inorganic electrolyte: LiAlCl4 in liquid sulfur dioxide. Concentrated solutions show a very high conductivity when compared with typical electrolytes for lithium ion batteries that are based on organic solvents. Our investigations include conductivity measurements and measurements of transference numbers via nuclear magnetic resonance (NMR and by a classical direct method, Hittorf’s method. For the use of Hittorf’s method, it is necessary to measure the concentration of the electrolyte in a selected cell compartment before and after electrochemical polarization very precisely. This task was finally performed by potentiometric titration after hydrolysis of the salt. The Haven ratio was determined to estimate the association behavior of this very concentrated electrolyte solution. The measured unusually high transference number of the lithium cation of the studied most concentrated solution, a molten solvate LiAlCl4 × 1.6SO2, makes this electrolyte a promising alternative for lithium ion cells with high power ability.

Finite elements-based 2D theoretical analysis of the effect of IEX membrane thickness and salt solution residence time on the ion transport within a salinity gradient power reverse electrodialysis half cell pair

OpenAIRE

Etienne, Brauns

2013-01-01

Reverse electrodialysis electrical power generation is based on the transport of salt ions through ion conductive membranes. The ion flux, equivalent to an electric current, results from a salinity gradient, induced by two salt solutions at significantly different concentrations. Such equivalent electric current in combination with the corresponding electrochemical potential difference across the membrane, equivalent to an electric potential, results in a battery equivalency. While having a c...

Mathematical model of salt cavern leaching for gas storage in high-insoluble salt formations.

Science.gov (United States)

Li, Jinlong; Shi, Xilin; Yang, Chunhe; Li, Yinping; Wang, Tongtao; Ma, Hongling

2018-01-10

A mathematical model is established to predict the salt cavern development during leaching in high-insoluble salt formations. The salt-brine mass transfer rate is introduced, and the effects of the insoluble sediments on the development of the cavern are included. Considering the salt mass conservation in the cavern, the couple equations of the cavern shape, brine concentration and brine velocity are derived. According to the falling and accumulating rules of the insoluble particles, the governing equations of the insoluble sediments are deduced. A computer program using VC++ language is developed to obtain the numerical solution of these equations. To verify the proposed model, the leaching processes of two salt caverns of Jintan underground gas storage are simulated by the program, using the actual geological and technological parameters. The same simulation is performed by the current mainstream leaching software in China. The simulation results of the two programs are compared with the available field data. It shows that the proposed software is more accurate on the shape prediction of the cavern bottom and roof, which demonstrates the reliability and applicability of the model.

Densities and solubilities of Glycylglycine and Glycyl-L-Alanine in Aqueous Electrolyte Solutions

DEFF Research Database (Denmark)

Breil, Martin Peter; Mollerup, Jørgen; Rudolph, E. Susanne J.

2004-01-01

Solubilities of glycylglycine and glycyl-L-alanine in aqueous electrolyte solutions containing 0-6 molal NaCl, 0-1 molal Na2SO4, and 0-1 molal (NH4)(2)SO4, have been determined experimentally at 298.15 K and atmospheric pressure. The solubility of glycylglycine and glycyl-L-alanine in pure water...... is 1.74 and 4.78 mol/kg of water, respectively. The solubility of glycylglycine in salt solutions of NaCl, Na2SO4, and (NH4)(2)SO4 show a moderate salting-in effect. The solubility of glycyl-L-alanine show a minor or no salting-in effect at low salt concentrations and a moderate salting-out effect...... at higher salt concentrations in NaCl and Na2SO4, and in (NH4)(2)SO4 the solubility is almost constant. The densities of the solutions have been determined experimentally, and the volume expansions by dissolving salt and dipeptide in water have been calculated. (C) 2003 Elsevier B.V. All rights reserved....

Calculating potential of mean force between like-charged nanoparticles: A comprehensive study on salt effects

International Nuclear Information System (INIS)

Wu, Yuan-Yan; Wang, Feng-Hua; Tan, Zhi-Jie

2013-01-01

Ions are critical to the structure and stability of polyelectrolytes such as nucleic acids. In this work, we systematically calculated the potentials of mean force between two like-charged nanoparticles in salt solutions by Monte Carlo simulations. The pseudo-spring method is employed to calculate the potential of mean force and compared systematically with the inversed-Boltzmann method. An effective attraction is predicted between two like-charged nanoparticles in divalent/trivalent salt solution and such attraction becomes weakened at very high salt concentration. Our analysis reveals that for the system, the configuration of ion-bridging nanoparticles is responsible for the attraction, and the invasion of anions into the inter-nanoparticles region at high salt concentration would induce attraction weakening rather than the charge inversion effect. The present method would be useful for calculating effective interactions during nucleic acid folding.

Corrosion behaviour of the UO2 pellet in corrosive solutions using electrochemical Technique

International Nuclear Information System (INIS)

Taftanzani, A.; Sucipto; Lahagu, F.; Irianto, B.

1996-01-01

The UO 2 electrodes has been made from the local product of UO 2 pellets. The corrosion behaviour of the UO 2 pellets is affected by solution, by pH value and by concentration of salt solution. Investigation into corrosion behaviour of UO 2 electrodes have been carried out in saturated salt solutions using electrochemical technique. The saturated solutions have been made from salts NaCl, Na 2 CO 3 , Na 2 SO 4 and Na 3 PO 4 . The pH value have been done over range 1 pH 10 and the salt concentration (C) over range 0,001 mol/l C 1,0 mol/l, Na 2 CO 3 solution produced the lowest corrosion rates of UO 2 pellets. Those rates were relative constant in the range of pH = 4 - 8. The results indicate an influence of the Na 2 CO 3 concentrations on the corrosions on the corrosion rate, and the lowest rates occur in 0,10 mol/l Na 2 CO 3 . The lowest corrosion rate was 0.3388 mil/year in 0.10 mol/l Na 2 CO 3 by pH = 4. (author)

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.

Decolorization of reactive black 5 using dielectric barrier discharge in the presence of inorganic salts

Directory of Open Access Journals (Sweden)

Dojčinović Biljana P.

2012-01-01

Full Text Available Inorganic salts improve the coloration of textiles, which increase pollution load on dyehouse effluent in general. Decolorization of reactive textile dye C.I. Reactive Black 5 was studied using Advanced Oxidation Processes (AOPs in a non-thermal plasma reactor, based on coaxial water falling film Dielectric Barrier Discharge (DBD. Initial dye concentration in the solution was 40.0 mg L-1. The effects of addition of inorganic salt different high concentrations (NaCl, Na2SO4 and Na2CO3 on the degree of decolorization were studied. Recirculation of dye solution through the DBD reactor with applied energy density 45-315 kJ L-1 was used. The influence of residence time was investigated after 5 minutes and 24 hours of plasma treatment. Decolorization of the dyes was monitored by spectrophotometric measurement. Changes of pH values and the conductivity of dye solution after each recirculation were tested. The most effective decolorization of over 90% was obtained with the addition of NaCl (50 g L-1, applied energy density of 135 kJ L-1 and after residence time of 24 hours of plasma treatment. Decolorization of solutions containing inorganic salts Na2SO4 and Na2CO3 were lower than for the solution without salt.

Flotation of copper-bearing shale in solutions of inorganic salts and organic reagents

OpenAIRE

Ratajczak Tomasz

2017-01-01

Flotation data on copper-bearing shale in aqueous solutions of inorganic electrolytes (NaCl, Na2SO4, KPF6, NH4Cl) and organic reagents (ethylamine, propylamine) as frothers were presented and discussed. The relationships between shale flotation, surface tension of aqueous solution and foam height during bubbling with air in the flotation system were presented. It has been found that flotation of shale in the presence of inorganic salts the yield was directly proportional to the surface tensio...

Bases, Assumptions, and Results of the Flowsheet Calculations for the Decision Phase Salt Disposition Alternatives

Energy Technology Data Exchange (ETDEWEB)

Elder, H.H.

2001-07-11

The HLW salt waste (salt cake and supernate) now stored at the SRS must be treated to remove insoluble sludge solids and reduce the soluble concentration of radioactive cesium radioactive strontium and transuranic contaminants (principally Pu and Np). These treatments will enable the salt solution to be processed for disposal as saltstone, a solid low-level waste.

Method for Cs-137 separation from the decontamination solutions

International Nuclear Information System (INIS)

Toropov, I.G.; Efremenkov, V.M.; Toropova, V.V.; Satsukevich, V.M.; Davidov, Yu.P.

1995-01-01

In this work results of investigations are presented on separation of radiocaesium from the decontamination solutions containing reducing agents (thiocarbamide). The scientific basis for radiocaesium removal from the solution focuses on the state of the radionuclide and its sorption behavior in the solution with a complicated composition. Then using a combination of sorption and ultrafiltration methods it would be possible to concentrate the radionuclide in a small volume and to purify the main part of the solution. As a sorbent for radiocaesium removal from the solution, a ferrocyanide based sorbent is proposed. Use of this sorbent is justified since its high selectivity and effectiveness for radiocaesium sorption from the solutions of different composition is well known. When synthesis of the sorbent is performed directly in the treating solution, two components as a minimum should be added to it, namely K 4 Fe(CN) 6 and metal ions of Ni-II, Co-II, Cu-II, etc. The results are presented which show the possibility of radiocaesium separation from the decontamination solutions (containing 60--100 g/l of salts) using sorption and membrane separation methods without the use of metal salts. At the same time by using FE-2 in solution in the presence of cyanide ions and thiocarbamide, it is possible to avoid the addition of metal salts (Ni, Cu, etc.). Utilization of the proposed method for spent decontamination solution treatment allows a relatively easy way to reduce the concentration of radiocaesium in solution on 2--4 orders of magnitudes, and to exclude the utilization of relatively expensive metal salts

Acemetacin cocrystals and salts: structure solution from powder X-ray data and form selection of the piperazine salt

Directory of Open Access Journals (Sweden)

Palash Sanphui

2014-03-01

Full Text Available Acemetacin (ACM is a non-steroidal anti-inflammatory drug (NSAID, which causes reduced gastric damage compared with indomethacin. However, acemetacin has a tendency to form a less soluble hydrate in the aqueous medium. We noted difficulties in the preparation of cocrystals and salts of acemetacin by mechanochemical methods, because this drug tends to form a hydrate during any kind of solution-based processing. With the objective to discover a solid form of acemetacin that is stable in the aqueous medium, binary adducts were prepared by the melt method to avoid hydration. The coformers/salt formers reported are pyridine carboxamides [nicotinamide (NAM, isonicotinamide (INA, and picolinamide (PAM], caprolactam (CPR, p-aminobenzoic acid (PABA, and piperazine (PPZ. The structures of an ACM–INA cocrystal and a binary adduct ACM–PABA were solved using single-crystal X-ray diffraction. Other ACM cocrystals, ACM–PAM and ACM–CPR, and the piperazine salt ACM–PPZ were solved from high-resolution powder X-ray diffraction data. The ACM–INA cocrystal is sustained by the acid...pyridine heterosynthon and N—H...O catemer hydrogen bonds involving the amide group. The acid...amide heterosynthon is present in the ACM–PAM cocrystal, while ACM–CPR contains carboxamide dimers of caprolactam along with acid–carbonyl (ACM hydrogen bonds. The cocrystals ACM–INA, ACM–PAM and ACM–CPR are three-dimensional isostructural. The carboxyl...carboxyl synthon in ACM–PABA posed difficulty in assigning the position of the H atom, which may indicate proton disorder. In terms of stability, the salts were found to be relatively stable in pH 7 buffer medium over 24 h, but the cocrystals dissociated to give ACM hydrate during the same time period. The ACM–PPZ salt and ACM–nicotinamide cocrystal dissolve five times faster than the stable hydrate form, whereas the ACM–PABA adduct has 2.5 times faster dissolution rate. The pharmaceutically acceptable

Acemetacin cocrystals and salts: structure solution from powder X-ray data and form selection of the piperazine salt.

Science.gov (United States)

Sanphui, Palash; Bolla, Geetha; Nangia, Ashwini; Chernyshev, Vladimir

2014-03-01

Acemetacin (ACM) is a non-steroidal anti-inflammatory drug (NSAID), which causes reduced gastric damage compared with indomethacin. However, acemetacin has a tendency to form a less soluble hydrate in the aqueous medium. We noted difficulties in the preparation of cocrystals and salts of acemetacin by mechanochemical methods, because this drug tends to form a hydrate during any kind of solution-based processing. With the objective to discover a solid form of acemetacin that is stable in the aqueous medium, binary adducts were prepared by the melt method to avoid hydration. The coformers/salt formers reported are pyridine carboxamides [nicotinamide (NAM), isonicotinamide (INA), and picolinamide (PAM)], caprolactam (CPR), p-aminobenzoic acid (PABA), and piperazine (PPZ). The structures of an ACM-INA cocrystal and a binary adduct ACM-PABA were solved using single-crystal X-ray diffraction. Other ACM cocrystals, ACM-PAM and ACM-CPR, and the piperazine salt ACM-PPZ were solved from high-resolution powder X-ray diffraction data. The ACM-INA cocrystal is sustained by the acid⋯pyridine heterosynthon and N-H⋯O catemer hydrogen bonds involving the amide group. The acid⋯amide heterosynthon is present in the ACM-PAM cocrystal, while ACM-CPR contains carboxamide dimers of caprolactam along with acid-carbonyl (ACM) hydrogen bonds. The cocrystals ACM-INA, ACM-PAM and ACM-CPR are three-dimensional isostructural. The carboxyl⋯carboxyl synthon in ACM-PABA posed difficulty in assigning the position of the H atom, which may indicate proton disorder. In terms of stability, the salts were found to be relatively stable in pH 7 buffer medium over 24 h, but the cocrystals dissociated to give ACM hydrate during the same time period. The ACM-PPZ salt and ACM-nicotinamide cocrystal dissolve five times faster than the stable hydrate form, whereas the ACM-PABA adduct has 2.5 times faster dissolution rate. The pharmaceutically acceptable piperazine salt of acemetacin exhibits superior

Exfoliation of graphite into graphene in aqueous solutions of inorganic salts.

Science.gov (United States)

Parvez, Khaled; Wu, Zhong-Shuai; Li, Rongjin; Liu, Xianjie; Graf, Robert; Feng, Xinliang; Müllen, Klaus

2014-04-23

Mass production of high-quality graphene sheets is essential for their practical application in electronics, optoelectronics, composite materials, and energy-storage devices. Here we report a prompt electrochemical exfoliation of graphene sheets into aqueous solutions of different inorganic salts ((NH4)2SO4, Na2SO4, K2SO4, etc.). Exfoliation in these electrolytes leads to graphene with a high yield (>85%, ≤3 layers), large lateral size (up to 44 μm), low oxidation degree (a C/O ratio of 17.2), and a remarkable hole mobility of 310 cm(2) V(-1) s(-1). Further, highly conductive graphene films (11 Ω sq(-1)) are readily fabricated on an A4-size paper by applying brush painting of a concentrated graphene ink (10 mg mL(-1), in N,N'-dimethylformamide). All-solid-state flexible supercapacitors manufactured on the basis of such graphene films deliver a high area capacitance of 11.3 mF cm(-2) and an excellent rate capability of 5000 mV s(-1). The described electrochemical exfoliation shows great promise for the industrial-scale synthesis of high-quality graphene for numerous advanced applications.

Solution-mediated phase transformation of haloperidol mesylate in the presence of sodium lauryl sulfate.

Science.gov (United States)

Greco, Kristyn; Bogner, Robin

2011-09-01

Forming a salt is a common way to increase the solubility of a poorly soluble compound. However, the solubility enhancement gained by salt formation may be lost due to solution-mediated phase transformation (SMPT) during dissolution. The SMPT of a salt can occur due to a supersaturated solution near the dissolving surface caused by pH or other solution conditions. In addition to changes in pH, surfactants are also known to affect SMPT. In this study, SMPT of a highly soluble salt, haloperidol mesylate, at pH 7 in the presence of a commonly used surfactant, sodium lauryl sulfate (SLS), was investigated. Dissolution experiments were performed using a flow-through dissolution apparatus with solutions containing various concentrations of SLS. Compacts of haloperidol mesylate were observed during dissolution in the flow-through apparatus using a stereomicroscope. Raman microscopy was used to characterize solids. The dissolution of haloperidol mesylate was significantly influenced by the addition of sodium lauryl sulfate. In conditions where SMPT was expected, the addition of SLS at low concentrations (0.1-0.2 mM) reduced the dissolution of haloperidol mesylate. In solutions containing concentrations of SLS above the critical micelle concentration (CMC) (10-15 mM), the dissolution of haloperidol mesylate increased compared to below the CMC. The solids recovered from solubility experiments of haloperidol mesylate indicated that haloperidol free base precipitated at all concentrations of SLS. Above 5 mM of SLS, Raman microscopy suggested a new form, perhaps the estolate salt. The addition of surfactant in solids that undergo solution-mediated phase transformation can add complexity to the dissolution profiles and conversion.

Lithium conducting ionic liquids based on lithium borate salts

Energy Technology Data Exchange (ETDEWEB)

Zygadlo-Monikowska, E.; Florjanczyk, Z.; Sluzewska, K.; Ostrowska, J.; Langwald, N.; Tomaszewska, A. [Warsaw University of Technology, Faculty of Chemistry, ul. Noakowskiego 3, 00-664 Warsaw (Poland)

2010-09-15

The simple reaction of trialkoxyborates with butyllithium resulted in the obtaining of new lithium borate salts: Li{l_brace}[CH{sub 3}(OCH{sub 2}CH{sub 2}){sub n}O]{sub 3}BC{sub 4}H{sub 9}{r_brace}, containing oxyethylene substituents (EO) of n=1, 2, 3 and 7. Salts of n {>=} 2 show properties of room temperature ionic liquid (RTIL) of low glass transition temperature, T{sub g} of the order from -70 to -80 C. The ionic conductivity of the salts depends on the number of EO units, the highest conductivity is shown by the salt with n = 3; in bulk its ambient temperature conductivity is 2 x 10{sup -5} S cm{sup -1} and in solution in cyclic propylene sulfite or EC/PC mixture, conductivity increases by an order of magnitude. Solid polymer electrolytes with borate salts over a wide concentration range, from 10 to 90 mol.% were obtained and characterized. Three types of polymeric matrices: poly(ethylene oxide) (PEO), poly(trimethylene carbonate) (PTMC) and two copolymers of acrylonitrile and butyl acrylate p(AN-BuA) were used in them as polymer matrices. It has been found that for systems of low salt concentration (10 mol.%) the best conducting properties were shown by solid polymer electrolytes with PEO, whereas for systems of high salt concentration, of the polymer-in-salt type, good results were achieved for PTMC as polymer matrix. (author)

[Influences of the mobile phase constitution, salt concentration and pH value on retention characters of proteins on the metal chelate column].

Science.gov (United States)

Li, R; Di, Z M; Chen, G L

2001-09-01

The effects of the nature and concentration of salts, pH value and competitive eluent in the mobile phase on the protein retention have been systematically investigated. A mathematical expression describing the protein retention in metal chelate chromatography has been derived. It is proposed that the eluting power of the salt solution can be expressed by the eluent strength exponent epsilon. According to the retention characters of protein under different chromatographic conditions, the interaction between the various metal chelate ligands and proteins is discussed. The protein retention on the metal chelate column is a cooperative interactions of coordination, electrostatic and hydrophobic interaction. For the strong combined metal column with proteins such as IDA-Cu, the coordination is the most important, and the electrostatic interaction is secondary in chromatographic process. However, for the weak combined metal columns with proteins such as IDA-Ni, IDA-Co and IDA-Zn, the electrostatic interaction between the metal chelate ligands and proteins is the chief one, while the coordination is the next in importance. When the mobile phase contains high concentration of salt which can't form complex with the immobilized metal, the hydrophobic interaction between the protein and stationary phase will be increased. As the interaction between the metal chelate ligand and proteins relates to chromatographic operating conditions closely, different elution processes may be selected for different metal chelate columns. The gradient elution is generally performed by the low concentration of salt or different pH for weakly combined columns with proteins, however the competitive elution procedure is commonly utilized for strongly combined column. The experiment showed that NH3 is an excellent competitive eluent. It isn't only give the efficient separation of proteins, but also has the advantages of cheapness, less bleeding of the immobilized metals and ease of controlling NH3

Determination of potassium concentration in salt water for residual beta radioactivity measurements

International Nuclear Information System (INIS)

Suarez-Navarro, J.A.; Pujol, Ll.

2004-01-01

High interferences may arise in the determination of potassium concentration in salt water. Several analytical methods were studied to determine which method provided the most accurate measurements of potassium concentration. This study is relevant for radiation protection because the exact amount of potassium in water samples must be known for determinations of residual beta activity concentration. The fitting algorithm of the calibration curve and estimation of uncertainty in potassium determinations were also studied. The reproducibility of the proposed analytical method was tested by internal and external validation. Furthermore, the residual beta activity concentration of several Spanish seawater and brackish river water samples was determined using the proposed method

Pore-scale dynamics of salt transport and distribution in drying porous media

International Nuclear Information System (INIS)

Shokri, Nima

2014-01-01

Understanding the physics of water evaporation from saline porous media is important in many natural and engineering applications such as durability of building materials and preservation of monuments, water quality, and mineral-fluid interactions. We applied synchrotron x-ray micro-tomography to investigate the pore-scale dynamics of dissolved salt distribution in a three dimensional drying saline porous media using a cylindrical plastic column (15 mm in height and 8 mm in diameter) packed with sand particles saturated with CaI 2 solution (5% concentration by mass) with a spatial and temporal resolution of 12 μm and 30 min, respectively. Every time the drying sand column was set to be imaged, two different images were recorded using distinct synchrotron x-rays energies immediately above and below the K-edge value of Iodine. Taking the difference between pixel gray values enabled us to delineate the spatial and temporal distribution of CaI 2 concentration at pore scale. Results indicate that during early stages of evaporation, air preferentially invades large pores at the surface while finer pores remain saturated and connected to the wet zone at bottom via capillary-induced liquid flow acting as evaporating spots. Consequently, the salt concentration increases preferentially in finer pores where evaporation occurs. Higher salt concentration was observed close to the evaporating surface indicating a convection-driven process. The obtained salt profiles were used to evaluate the numerical solution of the convection-diffusion equation (CDE). Results show that the macro-scale CDE could capture the overall trend of the measured salt profiles but fail to produce the exact slope of the profiles. Our results shed new insight on the physics of salt transport and its complex dynamics in drying porous media and establish synchrotron x-ray tomography as an effective tool to investigate the dynamics of salt transport in porous media at high spatial and temporal resolution

Fluorescent halite from Bochnia salt mine, Poland

Science.gov (United States)

Waluś, Edyta; Głąbińska, Dobrochna; Puławska, Aleksandra; Flasza, Michał; Manecki, Maciej

2016-04-01

The photoluminescence of selected halite crystals from Bochnia Salt Mine (Bochnia, Poland) were discovered in 2014. This is a result of contemporary precipitation from percolating waters. In most cases the fluorescence is observed in whole crystals or in zones of crystals. Only clear parts of transparent crystals are orange-red fluorescent in short UV light (320 nm). Chemical microanalysis by scanning electron microscopy/energy dispersive spectroscopy SEM/EDS indicates that this is activated by Mn and Pb. The concentration of Mn is similar in fluorescent and inactive salt and equals to 0.13 - 0.27 wt.%. The concentration of Pb, however, averages to 3.8 wt.% in fluorescent parts reaching only 1.9 wt.% elsewhere. There is no difference in the unit cell parameters determined by powder X-ray diffraction. The percolating waters contain some Mn (ca. 3.9 ppm) but the concentration of Pb is below the detection limits. The experiments of precipitation of halite from the solutions containing various concentrations of Mn and Pb were performed to simulate this fenomenon using solutions containing: 1 mg Pb/L and 80 mg Mn/L; 1 mg Pb/L and 0.8 mg Mn/L; 1 mg Pb/L and 0.6 mg Mn/L; and 0 mg Pb/L and 80 mg Mn/L. The results indicate that fluorescence is apparent when halite forms from solutions containing more than 0.8 mg Mn/L and more than 1 mg Pb/L. The presence of lead as co-activator is necessary requirement: Mn alone does not activate the fluorescence of halite. This is in accordance with the results of previous work (Murata et al., 1946; Sidike et al., 2002). Rock salt in the mine does not show fluorescence at all. Fluorescence of contemporary salt in Bochnia salt mine is a result of mining activity and slight, sporadic contamination with traces of Mn and Pb. This work is partially funded by AGH research grant no 11.11.140.319. Murata K. J., Smith R. L., 1946. Manganese and lead as coactivators of red fluorescence in halite, American Mineralogist, Volume 31, pages 527

Alteration of non-metallic barriers and evolution of solution chemistry in salt formations in Germany

International Nuclear Information System (INIS)

Herbert, H.J.; Becker, D.; Hagemann, S.; Meyer, Th.; Noseck, U.; Rubel, A.; Mauke, R.; Wollrath, J.

2005-01-01

Different Engineered Barrier Systems (EBS) materials considered in Germany for the sealing of repositories in salt formations are presented. Their long term behaviour in terms of interactions with salt solutions is discussed and evaluated. The discussed EBS materials are crushed salt, self sealing salt backfill, bentonite and salt concrete. Whereas the knowledge concerning the geochemical, geomechanical, hydrological and thermal behavior of crushed salt and salt concrete is well advanced further research is needed for other EBS materials. The self healing salt backfill has also been investigated in depth recently. In order to fully qualify this material large scale in situ experiments are still needed. The present knowledge on compacted bentonites in a salt environment is not yet sufficient for reliable predictions of the long-term performance in salt formations. The sealing concept of the low- and intermediate-level Radioactive Waste Repository Morsleben (ERAM) in a former rock salt and potash mine is presented. This concept is based on cementitious materials, i.e. salt concrete. The geochemical stability of different salt concretes in contact with brines expected in ERAM is addressed. It is shown how the results from leaching experiments and geochemical modelling are used in the safety analyses and how the chemical boundary conditions prevailing in the EBS influence the development of the permeability of the sealing system and thus control the radionuclide release. As a result of modelling the behaviour of the seals in the safety assessment it is shown, that the seals are corroded within a time span of about 20 000 years. The influence of the uncertainty in the model parameters on the safety of the repository was assessed by a variation of the initial permeability of the seal. The maximum dose rate resulting from the radionuclide release from ERAM is nearly independent of the variation of the initial permeability within four orders of magnitude. (authors)

IMPACT OF INCREASED ALUMINATE CONCENTRATIONS ON PROPERTIES OF SALTSTONE MIXES

International Nuclear Information System (INIS)

Harbour, J; Tommy Edwards, T; Erich Hansen, E; Vickie Williams, V

2007-01-01

One of the goals of the Saltstone variability study is to identify the operational and compositional variables that control or influence the important processing and performance properties of Saltstone mixes. The protocols developed in this variability study are ideally suited as a tool to assess the impact of proposed changes to the processing flow sheet for Liquid Waste Operations (LWO). One such proposal that is currently under consideration is to introduce a leaching step in the treatment of the High Level Waste (HLW) sludge to remove aluminum prior to vitrification at the Defense Waste Processing Facility (DWPF). This leachate would significantly increase the soluble aluminate concentrations as well as the free hydroxide ion concentration in the salt feed that will be processed at the Saltstone Processing Facility (SPF). Consequently, an initial study of the impact of increased aluminate concentration on the Saltstone grout properties was performed. The projected compositions and ranges of the aluminate rich salt stream (which includes the blending strategy) are not yet available and consequently, in this initial report, two separate salt stream compositions were investigated. The first stream starts with the previously projected baseline composition of the salt solution that will be fed to SPF from the Salt Waste Processing Facility (SWPF). The second stream is the solution that results from washing of the current Tank 51 sludge and subsequent transfer of the salt solution to Tank 11. The SWPF simulant has higher nitrate and lower free hydroxide than the Tank 11 simulant. In both of these cases, the aluminate was varied up to a maximum of 0.40 to 0.45M aluminate in order to evaluate the impact of increasing aluminate ion concentration on the grout properties. In general, the fresh grout properties of mixes made with SWPF and Tank 11 simulants were relatively insensitive to an increase in aluminate concentration in the salt solutions. However, the overall

Synergistic enhancement in the co-gelation of salt-soluble pea proteins and whey proteins.

Science.gov (United States)

Wong, Douglas; Vasanthan, Thava; Ozimek, Lech

2013-12-15

This paper investigated the enhancement of thermal gelation properties when salt-soluble pea proteins were co-gelated with whey proteins in NaCl solutions, using different blend ratios, total protein concentrations, pH, and salt concentrations. Results showed that the thermal co-gelation of pea/whey proteins blended in ratio of 2:8 in NaCl solutions showed synergistic enhancement in storage modulus, gel hardness, paste viscosity and minimum gelation concentrations. The highest synergistic enhancement was observed at pH 6.0 as compared with pH 4.0 and 8.0, and at the lower total protein concentration of 10% as compared with 16% and 22% (w/v), as well as in lower NaCl concentrations of 0.5% and 1.0% as compared with 1.5%, 2.0%, 2.5%, and 3.0% (w/v). The least gelation concentrations were also lower in the different pea/whey protein blend ratios than in pure pea or whey proteins, when dissolved in 1.0% or 2.5% (w/v) NaCl aqueous solutions. Copyright © 2013 Elsevier Ltd. All rights reserved.

Cation effect on small phosphonium based ionic liquid electrolytes with high concentrations of lithium salt

Science.gov (United States)

Chen, Fangfang; Kerr, Robert; Forsyth, Maria

2018-05-01

Ionic liquid electrolytes with high alkali salt concentrations have displayed some excellent electrochemical properties, thus opening up the field for further improvements to liquid electrolytes for lithium or sodium batteries. Fundamental computational investigations into these high concentration systems are required in order to gain a better understanding of these systems, yet they remain lacking. Small phosphonium-based ionic liquids with high concentrations of alkali metal ions have recently shown many promising results in experimental studies, thereby prompting us to conduct further theoretical exploration of these materials. Here, we conducted a molecular dynamics simulation on four small phosphonium-based ionic liquids with 50 mol. % LiFSI salt, focusing on the effect of cation structure on local structuring and ion diffusional and rotational dynamics—which are closely related to the electrochemical properties of these materials.

Numerical Simulation of the Freeze-Thaw Behavior of Mortar Containing Deicing Salt Solution.

Science.gov (United States)

Esmaeeli, Hadi S; Farnam, Yaghoob; Bentz, Dale P; Zavattieri, Pablo D; Weiss, Jason

2017-02-01

This paper presents a one-dimensional finite difference model that is developed to describe the freeze-thaw behavior of an air-entrained mortar containing deicing salt solution. A phenomenological model is used to predict the temperature and the heat flow for mortar specimens during cooling and heating. Phase transformations associated with the freezing/melting of water/ice or transition of the eutectic solution from liquid to solid are included in this phenomenological model. The lever rule is used to calculate the quantity of solution that undergoes the phase transformation, thereby simulating the energy released/absorbed during phase transformation. Undercooling and pore size effects are considered in the numerical model. To investigate the effect of pore size distribution, this distribution is considered using the Gibbs-Thomson equation in a saturated mortar specimen. For an air-entrained mortar, the impact of considering pore size (and curvature) on freezing was relatively insignificant; however the impact of pore size is much more significant during melting. The fluid inside pores smaller than 5 nm (i.e., gel pores) has a relatively small contribution in the macroscopic freeze-thaw behavior of mortar specimens within the temperature range used in this study (i.e., +24 °C to -35 °C), and can therefore be neglected for the macroscopic freeze-thaw simulations. A heat sink term is utilized to simulate the heat dissipation during phase transformations. Data from experiments performed using a low-temperature longitudinal guarded comparative calorimeter (LGCC) on mortar specimens fully saturated with various concentration NaCl solutions or partially saturated with water is compared to the numerical results and a promising agreement is generally obtained.

Effect of initial pH and temperature of iron salt solutions on formation of magnetite nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Gnanaprakash, G. [Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Mahadevan, S. [Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Jayakumar, T. [Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Kalyanasundaram, P. [Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Philip, John [Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India)]. E-mail: philip@igcar.gov.in; Raj, Baldev [Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India)

2007-05-15

We report the effect of initial pH and temperature of iron salt solutions on formation of magnetite (Fe{sub 3}O{sub 4}) nanoparticles during co-precipitation. We synthesized nanoparticles by keeping the initial pH at 0.7, 1.5, 3.0, 4.7, 5.7, 6.7 for two different temperatures of 30 and 60 deg. C. When the initial pH (prior to alkali addition) of the salt solution was below 5, the nanoparticles formed were 100% spinel iron oxide. Average size of the magnetite particles increases with initial pH until ferrihydrite is formed at a pH of 3 and the size remains the same till 4.7 pH. The percentage of goethite formed along with non-stoichiometric magnetite was 35 and 78%, respectively, when the initial pH of the solution was 5.7 and 6.7. As the reaction temperature was increased to 60 deg. C, maintaining a pH of 6.7, the amount of goethite increased from 78 to 100%. These results show that the initial pH and temperature of the ferrous and ferric salt solution before initiation of the precipitation reaction are critical parameters controlling the composition and size of nanoparticles formed. We characterize the samples using X-ray diffraction, transmission electron microscopy and vibrating sample magnetometer. The results of the present work provide the right conditions to synthesis pure magnetite nanoparticles, without goethite impurities, through co-precipitation technique for ferrofluid applications.

Electroerosion method for preparation of saturated solutions of ruthenium hydroxochloride

International Nuclear Information System (INIS)

Mikhalev, V.A.; Andrianov, G.A.; Zhadanov, B.V.; Ryazanov, A.I.

1987-01-01

A pilot plant for carrying out electroerosion processes using pulse current of high unit power is developed. The solution process of metallic Ru in concentrated HCl is investigated. The possibility of preparation of ruthenium hydroxochloride solutions of 300 g/l concentration is established; it gives the possibility of Ru solution under conditions similar to the process of salting out

Specific effects of certain salts on nitrogen metabolism of young corn seedlings

Directory of Open Access Journals (Sweden)

Mohammad Hatata

2014-01-01

Full Text Available The effect of sodium and magnesium chlorides and sulphates on nitrogen metabolism of corn seedlings and their constituent parts have been studied. Treatment with all salts led to a decrease in the nitrogen content of the seedling as a whole, and the decrease became more pronounced with the increase of salt concentration, though these concentrations were too low to induce any osmotic action. The same trend of changes was noticed as regards nonprotein-N, whereas the opposite was recorded in reference to the changes; of protein-N. Higher concentrations of the salt solutions led to leaching out of more nonprotein-N than did lower concentrations. The study of the distribution of nitrogenous constituents among the different organs of the seedling showed that while the total-N content of the whole seedling decreased with the increase of salt concentration, the total-N content of the roots decreased markedly, and the total-N content of the tops decreased also but less whereas, the total-N content of the grains increased with the increase of salt concentration as compared with that in the control. As a result of disturbances of nitrogen metabolism under salinization, more ammonia and amides were accumulated in all seedling organs.

Friedel's salt profiles from thermogravimetric analysis and thermodynamic modelling of Portland cement-based mortars exposed to sodium chloride solution

DEFF Research Database (Denmark)

Shi, Zhenguo; Geiker, Mette Rica; Lothenbach, Barbara

2017-01-01

Thermogravimetric analysis (TGA), powder X-ray diffraction (XRD) and thermodynamic modelling have been used to obtain Friedel's salt profiles for saturated mortar cylinders exposed to a 2.8 M NaCl solution. Comparison of the measured Friedel's salt profiles with the total chloride profiles...

The relationship between silicon availability, and growth and silicon concentration of the salt marsh halophyte Spartina anglica

NARCIS (Netherlands)

De Bakker, N.; Hemminga, M.A.; Van Soelen, J.

1999-01-01

Analysis of silicon concentrations of various halophytes from salt marshes in the S.W. Netherlands shows that the silicon concentration of Spartina anglica (Gramineae) is relatively high. To study the influence of dissolved Si concentrations on growth and plant tissue concentrations of S. anglica,

The Addition of White Turmeric (Curcuma zedoaria Concentrated Base on Quality Antioxidant Activity, Total Phenol, Protein Content and Salt Content of Salted Egg

Directory of Open Access Journals (Sweden)

Mu’addimah Mu’addimah

2017-03-01

Full Text Available The purposes of this research was to determine the effect of Curcuma zedoaria concentrated addition on quality antioxidant activity, total phenols, protein content and salt content of salted egg. The materials were duck’s egg, water, salt, and essence of white turmeric. The method was experiment using Complete Randomized Design (CRD with five treatments and three for replications. The Curcuma zedoaria juice research were divided into P0 (0%, P1 (10%, P2 (20%, P3 (30% and P4 (40%. Data was analyzed using Analysis of Variance (ANOVA and then continued by Duncan’s Multiple Range Test (DMRT, if it was found significant effect among treatmeants. The result showed that the addition of Curcuma zedoaria juice indicated highly significant different effect (P<0.01 on antioxidant activity, protein content and salt content, but significantly effect (P<0.05 on total phenol. The best treatment was the addition of Curcuma zedoaria juice 40% were indicated of antioxidant activity, total phenol, protein content and the salt content was 99.80 mg/g, 0.16%, 9.96%, 2.43% respectively.

Corrosion studies on type AISI 316L stainless steel and other materials in lithium-salt solutions

International Nuclear Information System (INIS)

Zheng, J.H.; Bogaerts, W.F.; Agema, K.; Phlippo, K.; Bruggeman, A.; Lorenzetto, P.; Embrechts, M.J.

1991-01-01

A possible concept for the blanket for next generation fusion devices is the lithium salt blanket, where lithium salt is dissolved in an aqueous coolant in order to provide for tritium. Type AISI 316L stainless steel has been considered as a structural material for such a blanket for NET (Next European Torus), and a systematic study of the corrosion behaviour of 316L stainless steel has been carried out in a number of lithium salt solutions. The experiments include cyclic potentiodynamic polarization measurement, crevice corrosion fatigue and stress corrosion cracking (SCC) tests. This paper presents a part of novel corrosion results concerning the compatibility of 316L steel and a series of other materials relevant to a fusion blanket environment. No major uniform corrosion problem has been observed, but localized corrosion, particularly corrosion fatigue and SCC, of 316L stainless steel have been found so far in a lithium hydroxide solution under some specific potential conditions. The critical electrochemical potential zones for SCC have been identified in the present study. (orig.)

Study of the transport characteristics of uranyl chloride in a highly concentrated aqueous solution of sodium chloride

International Nuclear Information System (INIS)

Murso, H.

1986-01-01

The purpose of this work was the study of the transport processes of uranyl chloride at various temperatures, in order to be able to estimate the danger potential of the intrusion of water during storage in salt form. For this the concentration dependency of the approximated principal diffusion coefficients of uranyl chloride in a table salt solution, which with a c(NaCl) = 5.2 mol/l is almost at the saturation point, was studied at 25, 40 and 50degC. The measurements were successful in the ternarian system UO 2 Cl 2 -NaCl-H 2 O with absorption optics. An unexpected temperature dependency of the diffusion coefficients was found, which reached its minimum at 40degC with UO 2 Cl 2 concentrations of less than 2x10 -2 mol/l. For comparison the diffusion coefficients were measured in the binary system UO 2 Cl 2 -H 2 O and compared with theoretical calculations. The cause for the poor correlation found here is thought to be the hydrolysis products, whose formation is strongly influenced by the foreign-electrolyte concentration (NaCl). For clarification, viscosity measurements and molar mass determinations (ultracentrifuge) will be done. Some pH-dependent hydrolysis equilibriums are being postulated and the equilibrium constants of uranyl hydroxo complexes are being determined by sedimentation analysis. (orig./RB) [de

Multisite Ion Model in Concentrated Solutions of Divalent Cations (MgCl2 and CaCl2): Osmotic Pressure Calculations

Science.gov (United States)

2015-01-01

Accurate force field parameters for ions are essential for meaningful simulation studies of proteins and nucleic acids. Currently accepted models of ions, especially for divalent ions, do not necessarily reproduce the right physiological behavior of Ca2+ and Mg2+ ions. Saxena and Sept (J. Chem. Theor. Comput.2013, 9, 3538–3542) described a model, called the multisite-ion model, where instead of treating the ions as an isolated sphere, the charge was split into multiple sites with partial charge. This model provided accurate inner shell coordination of the ion with biomolecules and predicted better free energies for proteins and nucleic acids. Here, we expand and refine the multisite model to describe the behavior of divalent ions in concentrated MgCl2 and CaCl2 electrolyte solutions, eliminating the unusual ion–ion pairing and clustering of ions which occurred in the original model. We calibrate and improve the parameters of the multisite model by matching the osmotic pressure of concentrated solutions of MgCl2 to the experimental values and then use these parameters to test the behavior of CaCl2 solutions. We find that the concentrated solutions of both divalent ions exhibit the experimentally observed behavior with correct osmotic pressure, the presence of solvent separated ion pairs instead of direct ion pairs, and no aggregation of ions. The improved multisite model for (Mg2+ and Ca2+) can be used in classical simulations of biomolecules at physiologically relevant salt concentrations. PMID:25482831

Effect of applied voltage and initial concentration to desalting NaCl solution using electrodialysis

International Nuclear Information System (INIS)

Boubakri, Ali; Gzara, Lassaad; Dhahbi, Mahmoud; Bouguecha, Salah

2009-01-01

The desalination process of electrodialysis is one of membrane separation that competes with reverse osmosis for desalination of brackish water and seawater. In this work water desalination using a laboratory electrodialysis was performed and evaluated to desalting aqueous solutions containing 5000, 10000 and 20000 mg/L NaCl at different applied potential (10, 15 and 20 V) and at a constant flow rate of 3 L/min. Nine electrodialysis runs were performed. The results showed that the increasing of applied potential and decreasing of NaCl concentration have an important effect to enhance the electrodialysis performance. The efficiencies of each experiment were evaluated as function of specific power consumption with the electrical energy consumed in electrodialysis stack. It was obtained that the specific power consumption increased when the salt concentration and applied voltage increased. A laboratory electrodialysis stack containing fifteen cation exchange membranes and fifteen anion exchange membranes of 0,716 m 2 total effective area was used.

Characterization of swollen structure of high-density polyelectrolyte brushes in salt solution by neutron reflectivity

Energy Technology Data Exchange (ETDEWEB)

Kobayashi, Motoyasu; Takahara, Atsushi [Institute for Materials Chemistry and Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395 (Japan); Terayama, Yuki [Graduate School of Engineering, Kyushu University (Japan); Hino, Masahiro [Reactor Research Institute, Kyoto University (Japan); Ishihara, Kazuhiko, E-mail: takahara@cstf.kyushu-u.ac.j [Graduate School of Engineering, University of Tokyo (Japan)

2009-08-01

Zwitterionic and cationic polyelectrolyte brushes on quartz substrate were prepared by surface-initiated atom transfer radical polymerization of 2-(methacryloyloxy)ethyl phosphorylcholine (MPC) and 2-(methacryloyloxy)ethyltrimethylammonium chloride (METAC), respectively. The effects of ionic strength on brush structure and surface properties of densely grafted polyelectrolyte brushes were analysed by neutron reflectivity (NR) measurements. NR at poly(METAC)/D{sub 2}O and poly(MPC)/D{sub 2}O interface revealed that the grafted polymer chains were fairly extended from the substrate surface, while the thickness reduction of poly(METAC) brush was observed in 5.6 M NaCl/D{sub 2}O solution due to the screening of the repulsive interaction between polycations by hydrated salt ions. Interestingly, no structural change was observed in poly(MPC) brush even in a salt solution probably due to the unique interaction properties of phosphorylcholine units.

Inhibition of salt precipitation, corrosion and corrosion fatigue of steel in neutral environments

International Nuclear Information System (INIS)

Mikhajlovskij, V.Ya.; Slobodyan, Z.V.; Soprunyuk, N.G.; Ivanov, A.M.

1983-01-01

Processes of salt precipitation, corrosion under dynamic and static conditions, are studied as well as corrosion fatigue of 20 and 40Kh steels in neutral aqueous media without and with the addition of compounds of several classes. The solution of calcium bicarbonate with the initial concentration [Ca(HCO 3 ) 2 ]=1.3 g/l and 3% NaCl solution in distilled water are used for investigation. The effectiveness index of salt precipitation inhibitor is determined by the change in the rate of calcium bicarbonate transformation into carbonate. The combination of results obtained permits to make the conclusion that tripolyphosphate and pyrophosphoric acid are rather perspective inhibitors of complex effect with low protective concentrations

Computational Analysis of Nanoparticles-Molten Salt Thermal Energy Storage for Concentrated Solar Power Systems

Energy Technology Data Exchange (ETDEWEB)

Kumar, Vinod [Univ. of Texas, El Paso, TX (United States)

2017-05-05

High fidelity computational models of thermocline-based thermal energy storage (TES) were developed. The research goal was to advance the understanding of a single tank nanofludized molten salt based thermocline TES system under various concentration and sizes of the particles suspension. Our objectives were to utilize sensible-heat that operates with least irreversibility by using nanoscale physics. This was achieved by performing computational analysis of several storage designs, analyzing storage efficiency and estimating cost effectiveness for the TES systems under a concentrating solar power (CSP) scheme using molten salt as the storage medium. Since TES is one of the most costly but important components of a CSP plant, an efficient TES system has potential to make the electricity generated from solar technologies cost competitive with conventional sources of electricity.

Silicon enhanced salt tolerance by improving the root water uptake and decreasing the ion toxicity in cucumber

Directory of Open Access Journals (Sweden)

Shiwen eWang

2015-09-01

Full Text Available Although the effects of silicon application on enhancing plant salt tolerance have been widely investigated, the underlying mechanism has remained unclear. In this study, seedlings of cucumber, a medium silicon accumulator plant, grown in 0.83 mM silicon solution for two weeks were exposed to 65 mM NaCl solution for another one week. The dry weight and shoot/root ratio were reduced by salt stress, but silicon application significantly alleviated these decreases. The chlorophyll concentration, net photosynthetic rate, transpiration rate and leaf water content were higher in plants treated with silicon than in untreated plants under salt stress conditions. Further investigation showed that salt stress decreased root hydraulic conductance (Lp, but that silicon application moderated this salt-induced decrease in Lp. The higher Lp in silicon-treated plants may account for the superior plant water balance. Moreover, silicon application significantly decreased Na+ concentration in the leaves while increasing K+ concentration. Simultaneously, both free and conjugated types of polyamines were maintained at high levels in silicon-treated plants, suggesting that polyamines may be involved in the ion toxicity. Our results indicate that silicon enhances the salt tolerance of cucumber through improving plant water balance by increasing the Lp and reducing Na+ content by increasing polyamine accumulation.

Molecular Structure of Salt Solutions: A New View of the Interface with Implications for Heterogeneous Atmospheric Chemistry

Czech Academy of Sciences Publication Activity Database

Jungwirth, Pavel; Tobias, D. J.

2001-01-01

Roč. 105, č. 43 (2001), s. 10468-10472 ISSN 1089-5647 R&D Projects: GA MŠk LN00A032 Institutional research plan: CEZ:AV0Z4040901 Keywords : air-solution interface * salt solutions * molecular dynamics Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.379, year: 2001

An efficient way to prepare silver nanorods in high concentration by polyol method without adding other metal or salt

International Nuclear Information System (INIS)

Chen Yong; Guan Jianguo; Xie Hongquan

2012-01-01

Using ethylene glycol as solvent and reductant, polyvinyl pyrrolidone(PVP) as capping agent under the action of appropriately preformed silver crystal seeds and controlled addition rates of silver nitrate and PVP solution, silver nanorods with length of 2–15 μm and diameter of 200–880 nm can be obtained in high concentration of AgNO 3 as 0.50 M. In the absence of the preformed seeds, nanorods cannot be obtained as the main product, if the AgNO 3 concentration is over 0.10 M. It is necessary to use the appropriately preformed silver crystal seeds for the high concentration preparation of silver nanorods. Transmission Electron Microscopy images showed that Ag seeds preformed at appropriate silver nitrate concentrations exhibited the multiply twinned particles of decahedral shape(MTPs), which formed Ag nanorods in the presence of PVP. Through study of the effects of various factors on the nanostructure of silver, the favorable conditions are: appropriately preformed seeds concentration at 6.54–9.81 mM, addition rate of AgNO 3 solution at 0.30–0.43 mL min −1 and molar ratio of PVP/AgNO 3 at 1.1–1.4, in order to control the crystal growth rate of silver matching the reduction rate of AgNO 3 by ethylene glycol. The nanorods obtained were characterized by Scanning Electron Microscopy, EDX, XRD, Raman spectrometry, Infrared Spectrophotometry and Ultraviolet Spectrophotometry. On the base of the above results, the mechanism of rates matching for obtaining silver nanorods was briefly discussed. This method is a simple, facile and economical method using high concentration with high yield without using other metal or salt to massively synthesize silver nanorods through adding preformed silver seeds to control the reduction rate of silver nitrate and the crystal growth rate of silver nanorods. As compared to the conventional polyol method using lower silver nitrate concentration, this method can save ethylene glycol used and time of operation and the as

Interactions between halloysite nanotubes and poly(styrene sulfonate) in solution

Energy Technology Data Exchange (ETDEWEB)

Kim, Jae Heon; Ryu, Jung Ju; Shin, Joo Huei; Lee, Hoik; Sohn, Dae Won [Dept. of Chemistry and Research Institute for Convergence of Basic Science, Hanyang University, Seoul (Korea, Republic of); Kim, Ick Soo [Nano Fusion Technology Research Lab, Division of Frontier Fibers, Institute for Fiber Engineering (IFES), Interdisciplinary Cluster for Cutting Edge Research (ICCER), Shinshu University, Nagano (Japan)

2017-01-15

The interaction between halloysite nanotubes (HNT) and poly(styrene sulfonate) (PSS) in aqueous solution was investigated by dynamic light scattering. Dynamic behavior of HNT/PSS was observed with different salt, HNT, and PSS concentrations. The HNT colloids were stabilized by PSS over a wide range of HNT concentrations, and HNT suspension in dilute solution formed stable HNT/PSS particles. On the other hand, HNT particles aggregated as sediments at higher concentrations due to strong attraction among HNT rods, and HNT aggregates were stabilized by additional PSS. The interactions between HNT and PSS are described by the van der Waals–London force (VDWL). The stabilization process of HNT/PSS particles in salt solution was proposed by comparing the hydrodynamic radii and apparent intensities of samples. The results demonstrate that electrostatic, steric, and depletion stabilization processes are responsible for the stable dispersion of HNT even at high concentration.

Modification of thermal sensitivity of Chinese hamster cells by exposure to solutions of monovalent and divalent cationic salts

International Nuclear Information System (INIS)

Raaphorst, G.P.; Azzam, E.I.; Vadasz, J.

1984-06-01

Chinese hamster V79 cells were heated in culture medium or in 0.155-mol.dm -3 solutions of LiCl, NaCl, KCl, MgCl 2 , CaCl 2 and BaCl 2 . The presence of any one of these ionic solutions during heating increased the thermal sensitivity of the cells. The order of increased thermal sensitivity was KCl > LiCl > NaCl for the monovalent salts and BaCl 2 > MgCl 2 > CaCl 2 for the divalent cation salts. The addition of glucose to LiCl or NaCl solutions did not reduce the thermal sensitization caused by these solutions. When cells were sensitized by LiCl or NaCl treatment, a change in pH from 7.2 to 6.6 did not further increase thermal sensitivity. These data show that nutrient and ionic factors and their interplay are involved in cellular thermal sensitivity

Membrane crystallization for recovery of salts from produced water

DEFF Research Database (Denmark)

Quist-Jensen, Cejna Anna; Jensen, Henriette Casper; Ali, Aamer

Membrane Crystallization (MCr) is a novel technology able to recover freshwater and high-purity salts from complex solutions and therefore, is suggested for a better exploitation of wastewater streams. Unlike other membrane processes, MCr is not limited by high concentrations and, therefore, the ......, the membrane maintained its hydrophobic nature despite that produced water contained oil residues. Conductivity and HPLC was utilized to analyze the quality of the permeate stream......., the solutions can be treated to achieve saturation level. Hereby different salts can be precipitated and directly recovered from various streams. In this study, it is shown that MCr is able to treat produced water by producing clean water and simultaneously NaCl crystals. The recovered crystals exhibited high...

Relating soil solution Zn concentration to diffusive gradients in thin films measurements in contaminated soils.

Science.gov (United States)

Degryse, Fien; Smolders, Erik; Oliver, Ian; Zhang, Hao

2003-09-01

The technique of diffusive gradients in thin films (DGT) has been suggested to sample an available fraction of metals in soil. The objectives of this study were to compare DGT measurements with commonly measured fractions of Zn in soil, viz, the soil solution concentration and the total Zn concentration. The DGT technique was used to measure fluxes and interfacial concentrations of Zn in three series of field-contaminated soils collected in transects toward galvanized electricity pylons and in 15 soils amended with ZnCl2 at six rates. The ratio of DGT-measured concentration to pore water concentration of Zn, R, varied between 0.02 and 1.52 (mean 0.29). This ratio decreased with decreasing distribution coefficient, Kd, of Zn in the soil, which is in agreement with the predictions of the DGT-induced fluxes in soils (DIFS) model. The R values predicted with the DIFS model were generally larger than the observed values in the ZnCl2-amended soils at the higher Zn rates. A modification of the DIFS model indicated that saturation of the resin gel was approached in these soils, despite the short deployment times used (2 h). The saturation of the resin with Zn did not occur in the control soils (no Zn salt added) or the field-contaminated soils. Pore water concentration of Zn in these soils was predicted from the DGT-measured concentration and the total Zn content. Predicted values and observations were generally in good agreement. The pore water concentration was more than 5 times underpredicted for the most acid soil (pH = 3) and for six other soils, for which the underprediction was attributed to the presence of colloidal Zn in the soil solution.

Enhanced cycling performance of a Li metal anode in a dimethylsulfoxide-based electrolyte using highly concentrated lithium salt for a lithium-oxygen battery

Science.gov (United States)

Togasaki, Norihiro; Momma, Toshiyuki; Osaka, Tetsuya

2016-03-01

Stable charge-discharge cycling behavior for a lithium metal anode in a dimethylsulfoxide (DMSO)-based electrolyte is strongly desired of lithium-oxygen batteries, because the Li anode is rapidly exhausted as a result of side reactions during cycling in the DMSO solution. Herein, we report a novel electrolyte design for enhancing the cycling performance of Li anodes by using a highly concentrated DMSO-based electrolyte with a specific Li salt. Lithium nitrate (LiNO3), which forms an inorganic compound (Li2O) instead of a soluble product (Li2S) on a lithium surface, exhibits a >20% higher coulombic efficiency than lithium bis(trifluoromethanesulfonyl)imide, lithium bis(fluorosulfonyl)imide, and lithium perchlorate, regardless of the loading current density. Moreover, the stable cycling of Li anodes in DMSO-based electrolytes depends critically on the salt concentration. The highly concentrated electrolyte 4.0 M LiNO3/DMSO displays enhanced and stable cycling performance comparable to that of carbonate-based electrolytes, which had not previously been achieved. We suppose this enhancement is due to the absence of free DMSO solvent in the electrolyte and the promotion of the desolvation of Li ions on the solid electrolyte interphase surface, both being consequences of the unique structure of the electrolyte.

Effect of Salt Forms of Chitosan on In Vitro Permeability ...

African Journals Online (AJOL)

CS-salt solution concentration of 0.01 %w/v, accumulation of FD-4 in the acceptor ... Chitosan (CS) is used as a novel carrier of drugs for ... (FBS), glutamine, sodium pyruvate and penicillin- .... mitochondrial dehydrogenases in living but not in.

Increased water resistance of paper treated with amylose-fatty ammonium salt inclusion complexes

Science.gov (United States)

Amylose inclusion complexes were prepared from high amylose corn starch and the HCl salts of hexadecylamine and octadecylamine. Solutions of the complexes were applied to paper at concentrations of 2-4%. After the treated papers were dried, sodium hydroxide solution was applied to convert the adsorb...

Prolonged river water pollution due to variable-density flow and solute transport in the riverbed

Science.gov (United States)

Jin, Guangqiu; Tang, Hongwu; Li, Ling; Barry, D. A.

2015-04-01

A laboratory experiment and numerical modeling were used to examine effects of density gradients on hyporheic flow and solute transport under the condition of a solute pulse input to a river with regular bed forms. Relatively low-density gradients due to an initial salt pulse concentration of 1.55 kg m-3 applied in the experiment were found to modulate significantly the pore-water flow and solute transport in the riverbed. Such density gradients increased downward flow and solute transport in the riverbed by factors up to 1.6. This resulted in a 12.2% increase in the total salt transfer from the water column to the riverbed over the salt pulse period. As the solute pulse passed, the effect of the density gradients reversed, slowing down the release of the solute back to the river water by a factor of 3.7. Numerical modeling indicated that these density effects intensified as salt concentrations in the water column increased. Simulations further showed that the density gradients might even lead to unstable flow and result in solute fingers in the bed of large bed forms. The slow release of solute from the bed back to the river led to a long tail of solute concentration in the river water. These findings have implications for assessment of impact of pollution events on river systems, in particular, long-term effects on both the river water and riverbed due to the hyporheic exchange.

USE CELLULOSE FOR CLEANING CONCENTRATED SUGAR SOLUTIONS

Directory of Open Access Journals (Sweden)

N. G. Kul’neva

2015-01-01

Full Text Available Summary. Producing high quality intermediate products in the boiling-crystallization station is an actual problem of sugar production. In the production of white sugar brown sugar syrup is not further purified that decreases the quality of the end product. Studies have been conducted using cellulose as an adsorbent for the purification of concentrated sugar solutions, having affinity to dyes and other impurities. Research have been carried out with the intermediate products of the Lebedyan sugar plant. Test results have shown cellulose ability to adsorb the dyes in sugar production. The influence of the adsorbent concentration and the mass fraction of solids in the syrup on the decolorization effect has been studied; rational process parameters have been obtained. It has been found that proceeding an additional adsorption purification of brown sugars syrup allows to reduce the solution color, increase the amount and quality of the end product. Adsorbing means, received from production wastes on the basis of organic resources, have many advantages: economical, environmentally friendly for disposal, safe to use, reliable and efficient in use. Conducted research on using cellulose as adsorbent for treatment of concentrated sugar solutions, having an affinity for colouring matter and other impurities. The experiments were carried out on the intermediates Lebedyanskiy sugar factory. The test results showed the ability of cellulose to adsorb coloring matter of sugar production. To evaluate the effect of bleaching depending on the mass fraction of dry substances prepared yellow juice filtration of sugar concentration of 55, 60, 65 % with subsequent adsorption purification of cellulose. The results of the experiment built adsorption isotherm of dyestuffs. The influence of the concentration of the adsorbent and a mass fraction of solids of juice filtration on the efficiency of decolorization obtained by rational parameters of the process. It is

THE INFLUENCE OF SALT CONTENT AT DIFFERENT CONCENTRATIONS OF TERASI TO THE SENSORY CHARACTERISTICS OF SAMBAL TERASI, THE CHILI SAUCE ADDED WITH TERASI.

Science.gov (United States)

Ambarita, N T Damanik; De Meulenaer, B

2015-01-01

The type of terasi (the Indonesian seafood fermented paste) and the ingredients used can give sambal terasi (ST), the chili sauce added with terasi, its identity and taste distinction. Inherit from its production, salt content differs the flavor(s) of product added with terasi. This research explored the role of terasi salt content, either from the origin of terasi or by salt adjustment, to the products acceptability and sensory characteristics perceived during subsequent sensorial evaluations. Six types of terasi were characterized based on the proximate and salt content, and prepared as STs with and without salt adjustment at several terasi concentrations. 118 panelists conducted sensory evaluations for overall acceptability at 12.5% terasi; at lower concentration specific tastes (sweet, bitter, salty, sour, umami, fishy and rebon) were characterized by 80 panelists. Results showed that the acceptance of ST is more due to its innate origin salt content and to the suitability saltiness perceived. The specific odor of terasi, combining with other taste(s), when prepared at higher terasi concentration as practiced in restaurant, home and commercial products showed masking effect(s). After saltiness adjusted, different types of terasi showed different taste characteristics. Preferred ST were different between higher and lower concentration. Better tastes characteristics and stronger spices taste were found at lower salt content (and terasi concentration).

Development of a mathematical model of a packed column for benzene removal from salt solutions

International Nuclear Information System (INIS)

Georgeton, G.K.

1989-01-01

A mathematical model of a packed column was developed to describe the removal of benzene from radioactive salt solutions at the Savannah River Site. The model was developed from existing, generalized mass transfer correlations for randomly dumped packing, and the correlations were adapted for structured packing. Thermophysical data specific to the solutions of interest were incorporated into the model. Verification of the code was completed using operating data from stripping columns at other locations

Nitrate concentrations in soil solutions below Danish forests

DEFF Research Database (Denmark)

Callesen, Ingeborg; Raulund-Rasmussen, Karsten; Gundersen, Per

1999-01-01

leaching in relation to land-use, a national monitoring programme has established sampling routines in a 7x7 km grid including 111 points in forests. During winters of 1986-1993, soil samples were obtained from a depth of 0-25, 25-50, 50-75 and 75-100 cm. Nitrate concentrations in soil solutions were...... species. A few sites deviated radically from the general pattern of low concentrations. The elevated concentrations recorded there were probably caused by high levels of N deposition due to emission from local sources or temporal disruptions of the N cycle. The nitrate concentration in the soil solution...

Context-driven Salt Seeking Test (Rats)

Science.gov (United States)

Chang, Stephen E.; Smith, Kyle S.

2018-01-01

Changes in reward seeking behavior often occur through incremental learning based on the difference between what is expected and what actually happens. Behavioral flexibility of this sort requires experience with rewards as better or worse than expected. However, there are some instances in which behavior can change through non-incremental learning, which requires no further experience with an outcome. Such an example of non-incremental learning is the salt appetite phenomenon. In this case, animals such as rats will immediately seek out a highly-concentrated salt solution that was previously undesired when they are put in a novel state of sodium deprivation. Importantly, this adaptive salt-seeking behavior occurs despite the fact that the rats never tasted salt in the depleted state, and therefore never tasted it as a highly desirable reward. The following protocol is a method to investigate the neural circuitry mediating adaptive salt seeking using a conditioned place preference (CPP) procedure. The procedure is designed to provide an opportunity to discover possible dissociations between the neural circuitry mediating salt seeking and salt consumption to replenish the bodily deficit after sodium depletion. Additionally, this procedure is amenable to incorporating a number of neurobiological techniques for studying the brain basis of this behavior.

Molecular insights into shellac film coats from different aqueous shellac salt solutions and effect on disintegration of enteric-coated soft gelatin capsules.

Science.gov (United States)

Al-Gousous, J; Penning, M; Langguth, P

2015-04-30

The purpose of this investigation was to study the effect of using different salts of shellac on the disintegration properties of shellac-based enteric coatings. In the last two decades, shellac has been increasingly used as an aqueous solution for enteric coating purposes, with the ammonium salt being the form typically used. Little investigation has been performed on using other salts, and therefore, this was the focus of our work. Enteric coatings, based on different shellac salts (ammonium, sodium, potassium and composite ammonium-sodium), were applied onto soft gelatin capsules. Disintegration testing of the coated soft gelatin capsules showed that alkali metal salts promote faster disintegration than ammonium salts. In order to determine the causes behind these differences, the solubility, thermal and spectroscopic properties of films cast from the different salts were investigated. The results show that films cast from ammonium-based salts of shellac are, unlike those cast from alkali metal-based salts, water-insoluble. Spectroscopic evidence suggests that this might be due to partial salt dissociation resulting in loss of ammonium as ammonia and reduced degree of shellac ionization during drying. In addition, oxidation of shellac aldehyde groups of the ammonium-based shellac salts could also play a role. And possible higher extent of shellac hydrolysis during the preparation of alkali metal salts might also be a factor. Therefore, the nature of the shellac salt used in the preparation of shellac-based aqueous coating solutions is a significant formulation factor affecting product performance. Copyright © 2014 Elsevier B.V. All rights reserved.

Retention of bile salts in micellar electrokinetic chromatography: relation of capacity factor to octanol-water partition coefficient and critical micellar concentration.

Science.gov (United States)

Lucangioli, S E; Carducci, C N; Tripodi, V P; Kenndler, E

2001-12-25

The capacity factors of 16 anionic cholates (from six bile salts, including their glyco- and tauro-conjugates) were determined in a micellar electrokinetic chromatography (MEKC) system consisting of buffer, pH 7.5 (phosphate-boric acid; 20 mmol/l) with 50 mmol/l sodium dodecyl sulfate (SDS) as micelle former and 10% acetonitrile as organic modifier. The capacity factors of the fully dissociated, negatively charged analytes (ranging between 0.2 and 60) were calculated from their mobilities, with a reference background electrolyte (BGE) without SDS representing "free" solution. For comparison, the capacity factors were derived for a second reference BGE where the SDS concentration (5 mmol/l) is close to the critical micellar concentration (CMC). The capacity factors are compared with the logarithm of the octanol-water partition coefficient, log Pow, as measure for lipophilicity. Clear disagreement between these two parameters is found especially for epimeric cholates with the hydroxy group in position 7. In contrast, fair relation between the capacity factor of the analytes and their CMC is observed both depending strongly on the orientation of the OH groups, and tauro-conjugation as well. In this respect the retention behaviour of the bile salts in MEKC seems to reflect their role as detergents in living systems, and might serve as model parameter beyond lipophilicity.

THE IMPACT OF DISSOLVED SALTS ON PASTES CONTAINING FLY ASH, CEMENT AND SLAG

Energy Technology Data Exchange (ETDEWEB)

Harbour, J.; Edwards, T.; Williams, V.

2009-09-21

The degree of hydration of a mixture of cementitious materials (Class F fly ash, blast furnace slag and portland cement) in highly concentrated alkaline salt solutions is enhanced by the addition of aluminate to the salt solution. This increase in the degree of hydration, as monitored with isothermal calorimetry, leads to higher values of dynamic Young's modulus and compressive strength and lower values of total porosity. This enhancement in performance properties of these cementitious waste forms by increased hydration is beneficial to the retention of the radionuclides that are also present in the salt solution. The aluminate ions in the solution act first to retard the set time of the mix but then enhance the hydration reactions following the induction period. In fact, the aluminate ions increase the degree of hydration by {approx}35% over the degree of hydration for the same mix with a lower aluminate concentration. An increase in the blast furnace slag concentration and a decrease in the water to cementitious materials ratio produced mixes with higher values of Young's modulus and lower values of total porosity. Therefore, these operational factors can be fine tuned to enhance performance properties of cementitious waste form. Empirical models for Young modulus, heat of hydration and total porosity were developed to predict the values of these properties. These linear models used only statistically significant compositional and operational factors and provided insight into those factors that control these properties.

Blanching, salting and sun drying of different pumpkin fruit slices.

Science.gov (United States)

Workneh, T S; Zinash, A; Woldetsadik, K

2014-11-01

The study was aimed at assessing the quality of pumpkin (Cucuribita Spp.) slices that were subjected to pre-drying treatments and drying using two drying methods (uncontrolled sun and oven) fruit accessions. Pre-drying had significant (P ≤ 0.05) effect on the quality of dried pumpkin slices. 10 % salt solution dipped pumpkin fruit slices had good chemical quality. The two-way interaction between drying methods and pre-drying treatments had significant (P ≤ 0.05) effect on chemical qualities. Pumpkin subjected to salt solution dipping treatment and oven dried had higher chemical concentrations. Among the pumpkin fruit accessions, pumpkin accession 8007 had the superior TSS, total sugar and sugar to acid ratio after drying. Among the three pre-drying treatment, salt solution dipping treatment had significant (P ≤ 0.05) effect and the most efficient pre-drying treatment to retain the quality of dried pumpkin fruits without significant chemical quality deterioration. Salt dipping treatment combined with low temperature (60 °C) oven air circulation drying is recommended to maintain quality of dried pumpkin slices. However, since direct sun drying needs extended drying time due to fluctuation in temperature, it is recommended to develop or select best successful solar dryer for use in combination with pre-drying salt dipping or blanching treatments.

SANS from Salt-Free Aqueous Solutions of Hydrophilic and Highly Charged Star-Branched Polyelectrolytes

Directory of Open Access Journals (Sweden)

François Boué

2016-06-01

Full Text Available Scattering functions of sodium sulfonated polystyrene (NaPSS star-branched polyelectrolytes with high sulfonation degrees were measured from their salt-free aqueous solutions, using the Small Angle Neutron Scattering (SANS technique. Whatever the concentration c, they display two maxima. The first, of abscissa q1*, is related to a position order between star cores and scales as q1* ∝ c1/3. The second, of abscissa q2*, is also observed in the scattering function of a semi-dilute solution of NaPSS linear polyelectrolytes. In the dilute regime (c < c*, non-overlapping stars, peak abscissa does not depend on concentration c and is just an intramolecular characteristic associated with the electrostatic repulsion between arms of the same star. In the semi-dilute regime, due to the star interpenetration, the scattering function – through the peak position, reflects repulsion between arms of the same star or of different stars. The c threshold between these distinct c-dependencies of q2* in the dilute and semi-dilute regimes is estimated as c*. Just as simple is the measurement of the geometrical radius R of the star obtained from the q1* value at c* through the relation 2R = 2π/q1*. By considering NaPSS stars of the same functionality with different degrees of polymerization per arm Na, we find R scaling linearly with Na, suggesting an elongated average conformation of the arms. This is in agreement with theoretical predictions and simulations. Meanwhile the value of q2* measured in the dilute regime does not allow any inhomogeneous counterion distribution inside the stars to be revealed.

Determining the Enthalpy of Vaporization of Salt Solutions Using the Cooling Effect of a Bubble Column Evaporator

Science.gov (United States)

Fan, Chao; Pashley, Richard M.

2016-01-01

The enthalpy of vaporization (?H[subscript vap]) of salt solutions is not easily measured, as a certain quantity of pure water has to be evaporated from a solution, at constant composition, and at a fixed temperature and pressure; then the corresponding heat input has to be measured. However, a simple bubble column evaporator (BCE) was used as a…

Changes in mechanical properties and morphology of elastomer coatings after immersion in salt solutions

Science.gov (United States)

Terán Arce, Fernando; Avci, Recep; Beech, Iwona; Cooksey, Keith; Wigglesworth-Cooksey, Barbara

2004-03-01

RTV11 (^TM GE Silicones) and Intersleek (^TM International Paints) are two elastomers of considerable significance to the navy and maritime industry for their application as fouling release coatings. Both materials are composed of polymeric matrices with embedded filler particles, which provide increased strength and durability to the elastomer. Using Atomic force microscopy (AFM), surface and bulk analysis techniques, we have found surface regions with microelastic properties, which correlate with the locations of filler particles inside the coatings. These particles are able to undergo elastic displacements of hundreds of nm inside the polymeric matrix during compression by the AFM tip. While elastic properties of Intersleek remain largely unchanged after immersion in salt solutions, roughening, embrittlement and stiffening occurs in RTV11 coatings depending on the amount of curing agent and humidity used during preparation and curing, respectively. Interestingly, such transformations are absent after immersion in pure water. In particle free regions, elastic moduli of RTV11 take values of 2 - 3 MPa before immersion in salt solutions. After immersion, those values increase 5 - 10 times.

Similarity of salt influences on the pH of buffers, polyelectrolytes, and proteins.

Science.gov (United States)

Voinescu, Alina E; Bauduin, Pierre; Pinna, M Cristina; Touraud, Didier; Ninham, Barry W; Kunz, Werner

2006-05-04

Changes in pH induced by the addition of electrolytes to buffers, polyelectrolytes (a polycarboxy polymethylene and a polyethyleneimine), and proteins (casein, whey, and lysozyme) solutions are explored systematically. The two buffer systems are triethanolamine/triethanolammonium chloride and citric acid/sodium citrate. These are chosen because of the similarity of their acid-base equilibria with those of amino acids predominant in most proteins, that is, amino acids that include carboxylate or ammonium groups in their structures. The pH of triethanolamine and of citrate buffers respectively increases and decreases when salt is added. At low electrolyte concentrations (buffer solutions. It is even possible to qualitatively predict these changes in protein solutions simply from the primary protein structure. At least in the systems considered here, the specific ion effects on pH seem to correlate with the bulk activity coefficients of the added electrolytes, at least at moderate salt concentrations.

Tailoring of poly(vinyl alcohol cryogels properties by salts addition

Directory of Open Access Journals (Sweden)

2009-05-01

Full Text Available The present paper aims to study the possibility to modify the properties of poly(vinyl alcohol (PVA hydrogels prepared in the presence of different salt types (Na2SO4, NaCl and NaNO3 in order to extend the nature of the salts already used in obtaining films or gels, to expand their concentration domains and to explain the increase of film strain, concomitantly with the increase of their crystallinity. The morphology of the PVA based hydrogels has been studied by Scanning Electronic Microscopy (SEM, the interaction between the PVA macromolecular chains and salts has been determined by Fourier Transform Infrared Spectroscopy (FTIR, while the mechanical properties of the cryogels have been investigated by oscillatory dynamic mechanical measurements. The gels swelling in water have been monitored by gravimetric method in order to evidence the alteration of the PVA cryogel properties such as crystallinity and porosity determined by the salt addition to the initial PVA aqueous solution. The data reported show that the ions present in the PVA solution influence the interaction between PVA-water and PVA-PVA chains; their influence on the salt-based PVA hydrogels follow the Hofmeister lyotropic series.

Sorption and permeation of solutions of chloride salts, water and methanol in a Nafion membrane

International Nuclear Information System (INIS)

Villaluenga, J.P.G.; Barragan, V.M.; Seoane, B.; Ruiz-Bauza, C.

2006-01-01

The sorption of water-methanol mixtures containing a dissolved chloride salt in a Nafion 117 membrane, and their transport through the membrane under the driving force of a pressure gradient, have been studied. Both type of experiments was performed by using five different salts: lithium chloride, sodium chloride, cesium chloride, magnesium chloride and calcium chloride. It was observed that both the permeation flow through the membrane and the membrane swelling increase significantly with the methanol content of the solutions. These facts are attributed to the increase in wet membrane porosity, which brings about the increase of the mobility of solvents in the membrane, besides the increase of the mobility of the polymer pendant chains. In contrast, the influence of the type of electrolyte on the membrane porosity and permeability is not very important, with the exception of the CsCl solutions, which is probably due to the small hydration ability of the Cs + ion

The Synthesis of Silver Nanoparticles Produced by Chemical Reduction of Silver Salt Solution

International Nuclear Information System (INIS)

Sri Budi Harmani; Dewi Sondari; Agus Haryono

2008-01-01

Described in this research are the synthesis of silver nanoparticle produced by chemical reduction of silver salt (silver nitrate AgNO 3 ) solution. As a reducer, sodium citrate (C 6 H 5 O 7 Na 3 ) was used. Preparation of silver colloid is done by using chemical reduction method. In typical experiment 150 ml of 1.10 -3 M AgNO 3 solution was heated with temperature variation such as 90, 100, 110 degree of Celsius. To this solution 15 ml of 1 % trisodium citrate was added into solution drop by drop during heating. During the process, solution was mixed vigorously. Solution was heated until colour's change is evident (pale yellow solution is formed). Then it was removed from the heating element and stirred until cooled to room temperature. Experimental result showed that diameter of silver nanoparticles in colloid solution is about 28.3 nm (Ag colloid, 90 o C); 19.9 nm (Ag colloid, 100 o C)and 26.4 nm (Ag colloid, 110 o C). Characterization of the silver nanoparticle colloid conducted by using UV-Vis Spectroscopy, Particles Size Analyzer (PSA) and Scanning Electron Microscope (SEM) indicate the produced structures of silver nanoparticles. (author)

Research Paper Silicon alleviates salt stress, decreases ...

African Journals Online (AJOL)

A greenhouse experiment was conducted to investigate the effects of different levels of silicon (Si) application on cut rose (Rosa xhybrida L.) 'Hot Lady' under two levels of salt stress. Four Si concentrations (0, 50, 100 and 150 ppm) as Si were combined with a 25 mM NaCl (EC 3.8) level in the nutrient solution supplied to ...

Fundamental Properties of Salts

Energy Technology Data Exchange (ETDEWEB)

Toni Y Gutknecht; Guy L Fredrickson

2012-11-01

Thermal properties of molten salt systems are of interest to electrorefining operations, pertaining to both the Fuel Cycle Research & Development Program (FCR&D) and Spent Fuel Treatment Mission, currently being pursued by the Department of Energy (DOE). The phase stability of molten salts in an electrorefiner may be adversely impacted by the build-up of fission products in the electrolyte. Potential situations that need to be avoided, during electrorefining operations, include (i) fissile elements build up in the salt that might approach the criticality limits specified for the vessel, (ii) electrolyte freezing at the operating temperature of the electrorefiner due to changes in the liquidus temperature, and (iii) phase separation (non-homogenous solution). The stability (and homogeneity) of the phases can be monitored by studying the thermal characteristics of the molten salts as a function of impurity concentration. Simulated salt compositions consisting of the selected rare earth and alkaline earth chlorides, with a eutectic mixture of LiCl-KCl as the carrier electrolyte, were studied to determine the melting points (thermal characteristics) using a Differential Scanning Calorimeter (DSC). The experimental data were used to model the liquidus temperature. On the basis of the this data, it became possible to predict a spent fuel treatment processing scenario under which electrorefining could no longer be performed as a result of increasing liquidus temperatures of the electrolyte.

Low-temperature hydrothermal synthesis of ZnO nanorods: Effects of zinc salt concentration, various solvents and alkaline mineralizers

Energy Technology Data Exchange (ETDEWEB)

Edalati, Khatereh, E-mail: kh_ed834@stu.um.ac.ir [Department of Metallurgical Engineering, Faculty of Engineering, Ferdowsi University of Mashhad (FUM) Campus, Azadi Sq., Mashhad, Khorasan Razavi (Iran, Islamic Republic of); Shakiba, Atefeh [Department of Material Science and Metallurgy, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Vahdati-Khaki, Jalil; Zebarjad, Seyed Mojtaba [Department of Metallurgical Engineering, Faculty of Engineering, Ferdowsi University of Mashhad (FUM) Campus, Azadi Sq., Mashhad, Khorasan Razavi (Iran, Islamic Republic of)

2016-02-15

Highlights: • We synthesized ZnO nanorods by a simple hydrothermal process at 60 °C. • Effects of zinc salt concentration, solvent and alkaline mineralizer was studied. • Increasing concentration of zinc salt changed ZnO nucleation system. • NaOH yielded better results in the production of nanorods in both solvents. • Methanol performed better in the formation of nanorods using the two mineralizers. - Abstract: ZnO has been produced using various methods in the solid, gaseous, and liquid states, and the hydrothermal synthesis at low temperatures has been shown to be an environmentally-friendly one. The current work utilizes a low reaction temperature (60 °C) for the simple hydrothermal synthesis of ZnO nanorod morphologies. Furthermore, the effects of zinc salt concentration, solvent type and alkaline mineralizer type on ZnO nanorods synthesis at a low reaction temperature by hydrothermal processing was studied. Obtained samples were analyzed using X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). Increasing the concentration of the starting zinc salt from 0.02 to 0.2 M changed ZnO nucleation system from the homogeneous to the heterogeneous state. The XRD results confirmed the production hexagonal ZnO nanostructures of with a crystallite size of 40.4 nm. Varying the experimental parameters (mineralizer and solvent) yielded ZnO nanorods with diameters ranging from 90–250 nm and lengths of 1–2 μm.

In Situ Production of Copper Oxide Nanoparticles in a Binary Molten Salt for Concentrated Solar Power Plant Applications.

Science.gov (United States)

Lasfargues, Mathieu; Stead, Graham; Amjad, Muhammad; Ding, Yulong; Wen, Dongsheng

2017-05-19

Seeding nanoparticles in molten salts has been shown recently as a promising way to improve their thermo-physical properties. The prospect of such technology is of interest to both academic and industrial sectors in order to enhance the specific heat capacity of molten salt. The latter is used in concentrated solar power plants as both heat transfer fluid and sensible storage. This work explores the feasibility of producing and dispersing nanoparticles with a novel one pot synthesis method. Using such a method, CuO nanoparticles were produced in situ via the decomposition of copper sulphate pentahydrate in a KNO₃-NaNO₃ binary salt. Analyses of the results suggested preferential disposition of atoms around produced nanoparticles in the molten salt. Thermal characterization of the produced nano-salt suspension indicated the dependence of the specific heat enhancement on particle morphology and distribution within the salts.

Extreme ductile deformation of fine-grained salt by coupled solution-precipitation creep and microcracking: Microstructural evidence from perennial Zechstein sequence (Neuhof salt mine, Germany)

Czech Academy of Sciences Publication Activity Database

Závada, Prokop; Desbois, G.; Schwedt, A.; Lexa, O.; Urai, J. L.

2012-01-01

Roč. 37, April (2012), s. 89-104 ISSN 0191-8141 R&D Projects: GA ČR GA14-15632S Institutional support: RVO:67985530 Keywords : rock salt * solution-precipitation creep * microcracking * Griffith crack * fluid inclusion trails Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Geology Impact factor: 2.285, year: 2012

An aqueous lithium salt blanket option for fusion power reactors

Energy Technology Data Exchange (ETDEWEB)

Steiner, D.; Varsamis, G. (Rensselaer Polytechnic Inst., Troy, NY (USA). Dept. of Nuclear Engineering and Engineering Physics); Deutsch, L.; Rathke, J. (Grumman Corp., Bethpage, NY (USA). Advanced Energy Systems); Gierszewski, P. (Canadian Fusion Fuels Technology Project (CFFTP), Mississauga, ON (Canada))

1989-04-01

An aqueous lithium salt blanket (ALSB) concept is proposed which could be the basis for either a power reactor blanket or a test module in an engineering test reactor. The design is based on an austenitic stainless steel structure, a beryllium multiplier, and a salt breeder concentration of about 32 g LiNO/sub 3/ per 100 cm/sup 3/ of H/sub 2/O. To limit tritium release rates, the salt breeder solution is separated from the water coolant circuit. The overall tritium system cost for a 2400 MW (fusion power) reactor is estimated to be 180 million Dollar US87 installed. (orig.).

Ionic diffusion and salt dissociation conditions of lithium liquid crystal electrolytes.

Science.gov (United States)

Saito, Yuria; Hirai, Kenichi; Murata, Shuuhei; Kishii, Yutaka; Kii, Keisuke; Yoshio, Masafumi; Kato, Takashi

2005-06-16

Salt dissociation conditions and dynamic properties of ionic species in liquid crystal electrolytes of lithium were investigated by a combination of NMR spectra and diffusion coefficient estimations using the pulsed gradient spin-echo NMR techniques. Activation energies of diffusion (Ea) of ionic species changed with the phase transition of the electrolyte. That is, Ea of the nematic phase was lower than that of the isotropic phase. This indicates that the aligned liquid crystal molecules prepared efficient conduction pathways for migration of ionic species. The dissociation degree of the salt was lower compared with those of the conventional electrolyte solutions and polymer gel electrolytes. This is attributed to the low concentration of polar sites, which attract the dissolved salt and promote salt dissociation, on the liquid crystal molecules. Furthermore, motional restriction of the molecules due to high viscosity and molecular oriented configuration in the nematic phase caused inefficient attraction of the sites for the salt. With a decreased dissolved salt concentration of the liquid crystal electrolyte, salt dissociation proceeded, and two diffusion components attributed to the ion and ion pair were detected independently. This means that the exchange rate between the ion and the ion pair is fairly slow once the salt is dissociated in the liquid crystal electrolytes due to the low motility of the medium molecules that initiate salt dissociation.

A discussion about maximum uranium concentration in digestion solution of U3O8 type uranium ore concentrate

International Nuclear Information System (INIS)

Xia Dechang; Liu Chao

2012-01-01

On the basis of discussing the influence of single factor on maximum uranium concentration in digestion solution,the influence degree of some factors such as U content, H 2 O content, mass ratio of P and U was compared and analyzed. The results indicate that the relationship between U content and maximum uranium concentration in digestion solution was direct ratio, while the U content increases by 1%, the maximum uranium concentration in digestion solution increases by 4.8%-5.7%. The relationship between H 2 O content and maximum uranium concentration in digestion solution was inverse ratio, the maximum uranium concentration in digestion solution decreases by 46.1-55.2 g/L while H 2 O content increases by 1%. The relationship between mass ratio of P and U and maximum uranium concentration in digestion solution was inverse ratio, the maximum uranium concentration in digestion solution decreases by 116.0-181.0 g/L while the mass ratio of P and U increase 0.1%. When U content equals 62.5% and the influence of mass ratio of P and U is no considered, the maximum uranium concentration in digestion solution equals 1 578 g/L; while mass ratio of P and U equals 0.35%, the maximum uranium concentration decreases to 716 g/L, the decreased rate is 54.6%, so the mass ratio of P and U in U 3 O 8 type uranium ore concentrate is the main controlling factor. (authors)

An alternating voltage battery with two salt-water oscillators

Science.gov (United States)

Cervellati, Rinaldo; Soldà, Roberto

2001-05-01

We built a simple alternating voltage battery that periodically reverses value and sign of its electromotive force (emf). This battery consists of two coupled concentration salt-water oscillators that are phase shifted by initially extracting some drops of salt solution from one of the two oscillators. Although the actual frequency (period: ˜30 s) and emf (˜±55 mV) is low, our battery is suitable to demonstrate a practical application of oscillating systems in the physical, chemical, or biological laboratory for undergraduates. Interpretation of the phenomenon is given.

Reflectance degradation of a secondary concentrator by nitrate salt vapor deposition in an open volumetric receiver configuration

Science.gov (United States)

Lahlou, Radia; Armstrong, Peter R.; Calvet, Nicolas; Shamim, Tariq

2017-06-01

Nitrate salt vapor deposition on the reflecting surface of a secondary concentrator placed on top of an open molten salt tank at 500 °C is investigated using a lab-scale setup over an 8h-exposure cycle. Deposition, consisting of mostly spherical particles, is characterized in terms of chemical composition using energy dispersive X-ray spectroscopy. The corresponding specular reflectance degradation both temporary (before washing off the salt deposits) and permanent (residual reflectance loss after cleaning), is measured at different incidence angles and at reference points located at different heights. Reflectance drop due to salt deposits is compared to the one resulting from dust deposition. Long-term reflectance degradation by means of corrosion needs to be further studied through suitable accelerated aging tests.

Distribution and metabolism of quaternary amines in salt marshes

Science.gov (United States)

King, Gary M.

1985-01-01

Quaternary amines such as glycine betaine (GBT) are common osmotically active solutes in much of the marine biota. GBT is accumulated by various bacteria, algae, higher plants, invertebrates, and vertebrates in response to salinity or water stresses; in some species, GBT occurs at tens to hundreds of millimolar concentrations and can account for a significant fraction of total nitrogen. Initial studies suggest that GBT is readily converted to two potential methane precursors, trimethylamine (TMA) and acetate, in anoxic sediments. TMA is apparently the most important methane precursor in surface sediments containing sulfate reducing bacteria. In salt marshes, the bulk of the methane formed may be due to the metabolism of TMA rather than other substrates. Current research is focussed on testing this hypothesis and on determining the role of quaternary amino osmoregulatory solutes in methane fluxes from marine environments. Preliminary studies have dealt with several problems: (1) determination of GBT concentrations in the dominant flora and fauna of salt marshes; (2) synthesis of radiolabelled GBT for metabolic studies; and (3) determination of fates of BGT in marine sediments using radiotracers. Both GC and HPLC techniques have been used to assay GBT concentrations in plant and animal tissues. S. alterniflora is probably the only significant source of GBT (and indirectly of methane) since the biomass and distribution of most other species is limited. Current estimates suggest that S. alterniflora GBT could account for most of the methane efflux from salt marshes.

Impact of solute concentration on the electrocatalytic conversion of dissolved gases in buffered solutions

KAUST Repository

Shinagawa, Tatsuya

2015-04-24

To maintain local pH levels near the electrode during electrochemical reactions, the use of buffer solutions is effective. Nevertheless, the critical effects of the buffer concentration on electrocatalytic performances have not been discussed in detail. In this study, two fundamental electrochemical reactions, oxygen reduction reaction (ORR) and hydrogen oxidation reaction (HOR), on a platinum rotating disk electrode are chosen as model gas-related aqueous electrochemical reactions at various phosphate concentrations. Our detailed investigations revealed that the kinetic and limiting diffusion current densities for both the ORR and HOR logarithmically decrease with increasing solute concentration (log|jORR|=-0.39c+0.92,log|jHOR|=-0.35c+0.73). To clarify the physical aspects of this phenomenon, the electrolyte characteristics are addressed: with increasing phosphate concentration, the gas solubility decrease, the kinematic viscosity of the solution increase and the diffusion coefficient of the dissolved gases decrease. The simulated limiting diffusion currents using the aforementioned parameters match the measured ones very well (log|jORR|=-0.43c+0.99,log|jHOR|=-0.40c+0.54), accurately describing the consequences of the electrolyte concentration. These alterations of the electrolyte properties associated with the solute concentration are universally applicable to other aqueous gas-related electrochemical reactions because the currents are purely determined by mass transfer of the dissolved gases. © 2015 The Authors.

Passivation behavior of Type 304 stainless steel in a non-aqueous alkyl carbonate solution containing LiPF6 salt

International Nuclear Information System (INIS)

Myung, Seung-Taek; Sasaki, Yusuke; Saito, Takamitsu; Sun, Yang-Kook; Yashiro, Hitoshi

2009-01-01

Passivation behavior of type 304 stainless steel in a non-aqueous alkyl carbonate solution containing LiPF 6 salt was studied using electrochemical polarization, X-ray photoelectron spectroscopy (XPS) and time of flight-secondary ion mass spectroscopy (ToF-SIMS). Cathodic polarization to 0 V vs. Li/Li + resulted in most but not complete reduction of the air-formed film from oxides to metal on the stainless steel, as confirmed by XPS. For complete elimination of the air-formed film, the surface of the stainless steel was scratched under anodic polarization conditions. At 3 V vs. Li/Li + where an anodic current peak appeared, only an indistinct layer was recognized on the newly scratched surface, according to ToF-SIMS analysis. Above 4 V vs. Li/Li + , substantial passive films were formed, which were composed of oxides and fluorides of iron and chromium. The origin of oxide was due to water contained in the non-aqueous alkyl carbonate solution, and that of fluorides were the result of the decomposition of electrolytic salt, LiPF 6 , especially at higher potential. The resultant passive films were stable in the non-aqueous alkyl carbonate solution containing LiPF 6 salt.

Effect of Hofmeister series salts on Absorptivity of aqueous solutions on Sodium polyacrylate

Science.gov (United States)

Korrapati, Swathi; Pullela, Phani Kumar; Vijayalakshmi, U.

2017-11-01

Sodium polyacrylate (SPA) is a popular super absorbent commonly used in children diapers, sanitary pads, adult diapers etc. The use of SPA is in force from past 30 years and the newer applications like as food preservant are evolving. SPA is recently discovered by our group for improvement of sensitivity of colorimetric agents. Though the discovery of improvement in sensitivity is phenomenal, the mechanism still remains a puzzle. A typical assay reagent contains colorimetric/fluorescent reagents, buffers, salts, stabilizers etc. These chemicals are known to influence the water absorptivity of SPA. If we were to perform chemical/biochemical assays on SPA absorbed reagents effect of salts and other excipients on colorimetric/fluorescence compounds absorbed on SPA is very important. The hofmeister series are standard for studying effect of salts on permeability, stability, aggregation, fluorescence quenching etc. We recently studied affect of urea, sodium chloride, ammonium sulfate, guanidine thiocayanate on fluorescence characteristics of fluorescence compounds and noted that except urea all other reagents have resulted in fluorescence quenching and urea had an opposite effect and increased the fluorescence intensity. This result was attributed to the different water structure around fluorescent in urea solution versus other chaotropic agents.

Influence of starch origin on rheological properties of concentrated aqueous solutions

Directory of Open Access Journals (Sweden)

Stojanović Željko P.

2011-01-01

Full Text Available The rheological properties of corn and potato starch concentrated aqueous solutions were investigated at 25ºC. The starches were previously dispersed in water and the solutions were obtained by heating of dispersions at 115-120ºC for 20 minutes. The solutions of potato starch were transparent, while the corn starch solutions were opalescent. The results of dynamic mechanical measurements showed that the values of viscosity, h, storage modulus, G′, and loss modulus, G″, of the corn starch solutions increased with the storage time. This phenomenon was not observed for the potato starch solutions. It was assumed that the increase of h, G′ and G″ is the result of starch solutions retrogradation. The potato starch solutions retrogradation did not occur probably because of the phosphates presence. The viscosity of 2 mass % corn starch solution is less than the viscosity of 2 mass % potato starch solution. By increasing the concentration of corn starch solution the gel with elastic behavior was formed. The corn starch solutions formed gel as early as at 4 mass % concentration, while potato starch solutions achieved the gel state at the concentration of 5 mass %. The value of exponent m (G′ and G″ µ wm during the transition of potato starch solutions to gel is 0.414, which gives the fractal dimensions for corn starch of 2.10. The obtained value of fractal dimension corresponds to slow aggregation. The corn starch solutions with the starch concentrations higher than 4 mass % form weak gels. For these solutions the values of modulus in rubber plateau were determined. It was found that the modulus in rubber plateau increased with the concentration by the exponent of 4.36. Such high exponent value was obtained in the case when the tridimensional network is formed, i.e. when supermolecular structures like associates or crystal domains are formed.

Are nanoscale ion aggregates present in aqueous solutions of guanidinium salts?

Science.gov (United States)

Hunger, Johannes; Niedermayer, Stefan; Buchner, Richard; Hefter, Glenn

2010-11-04

A detailed investigation using broadband dielectric relaxation spectroscopy (DRS) has been made of the aqueous solutions of guanidinium chloride and carbonate, GdmCl(aq) and Gdm₂CO₃(aq), at 25 °C. The spectra indicate that Gdm(+) ions, C(NH₂)₃(+), do not bind strongly to water nor are they hydrophobically hydrated; rather they appear to have a most unusual ability to dissolve in water without altering its dynamics. Although DRS is particularly sensitive to the presence of ion pairs, only weak ion pairing was detected in Gdm₂CO₃(aq) solutions and none at all in GdmCl(aq). Surprisingly, no evidence was found for the existence of the higher order homo- and heteroionic nanoscale aggregates that have been identified in recent years by Mason and co-workers using molecular dynamics simulations and neutron diffraction. Possible reasons for this discrepancy are discussed. The present DR spectra and other solution properties of GdmCl(aq) and Gdm₂CO₃(aq), such as apparent molar volumes and electrical conductivities, are shown to have strong similarities to those of the corresponding Na+ salts. However, such solutions also differ remarkably from their Na(+) analogues (and all other simple electrolytes in aqueous solution) in that their average water relaxation times correlate strongly with their bulk viscosities. The biological implications of the present results are briefly discussed.

In Situ Production of Copper Oxide Nanoparticles in a Binary Molten Salt for Concentrated Solar Power Plant Applications

Directory of Open Access Journals (Sweden)

Mathieu Lasfargues

2017-05-01

Full Text Available Seeding nanoparticles in molten salts has been shown recently as a promising way to improve their thermo-physical properties. The prospect of such technology is of interest to both academic and industrial sectors in order to enhance the specific heat capacity of molten salt. The latter is used in concentrated solar power plants as both heat transfer fluid and sensible storage. This work explores the feasibility of producing and dispersing nanoparticles with a novel one pot synthesis method. Using such a method, CuO nanoparticles were produced in situ via the decomposition of copper sulphate pentahydrate in a KNO3-NaNO3 binary salt. Analyses of the results suggested preferential disposition of atoms around produced nanoparticles in the molten salt. Thermal characterization of the produced nano-salt suspension indicated the dependence of the specific heat enhancement on particle morphology and distribution within the salts.

Excessive counterion condensation on immobilized ssDNA in solutions of high ionic strength.

Science.gov (United States)

Rant, Ulrich; Arinaga, Kenji; Fujiwara, Tsuyoshi; Fujita, Shozo; Tornow, Marc; Yokoyama, Naoki; Abstreiter, Gerhard

2003-12-01

We present experiments on the bias-induced release of immobilized, single-stranded (ss) 24-mer oligonucleotides from Au-surfaces into electrolyte solutions of varying ionic strength. Desorption is evidenced by fluorescence measurements of dye-labeled ssDNA. Electrostatic interactions between adsorbed ssDNA and the Au-surface are investigated with respect to 1), a variation of the bias potential applied to the Au-electrode; and 2), the screening effect of the electrolyte solution. For the latter, the concentration of monovalent salt in solution is varied from 3 to 1600 mM. We find that the strength of electric interaction is predominantly determined by the effective charge of the ssDNA itself and that the release of DNA mainly occurs before the electrochemical double layer has been established at the electrolyte/Au interface. In agreement with Manning's condensation theory, the measured desorption efficiency (etarel) stays constant over a wide range of salt concentrations; however, as the Debye length is reduced below a value comparable to the axial charge spacing of the DNA, etarel decreases substantially. We assign this effect to excessive counterion condensation on the DNA in solutions of high ionic strength. In addition, the relative translational diffusion coefficient of ssDNA in solution is evaluated for different salt concentrations.

Osmotic potential calculations of inorganic and organic aqueous solutions over wide solute concentration levels and temperatures

Energy Technology Data Exchange (ETDEWEB)

Cochrane, T. T., E-mail: agteca@hotmail.com [AGTECA S.A., 230 Oceanbeach Road, Mount Maunganui, Tauranga 3116 (New Zealand); Cochrane, T. A., E-mail: tom.cochrane@canterbury.ac.nz [Department of Civil and Natural Resources Engineering, University of Canterbury, Private Bag 4800, Christchurch 8140 (New Zealand)

2016-01-15

Purpose: To demonstrate that the authors’ new “aqueous solution vs pure water” equation to calculate osmotic potential may be used to calculate the osmotic potentials of inorganic and organic aqueous solutions over wide ranges of solute concentrations and temperatures. Currently, the osmotic potentials of solutions used for medical purposes are calculated from equations based on the thermodynamics of the gas laws which are only accurate at low temperature and solute concentration levels. Some solutions used in medicine may need their osmotic potentials calculated more accurately to take into account solute concentrations and temperatures. Methods: The authors experimented with their new equation for calculating the osmotic potentials of inorganic and organic aqueous solutions up to and beyond body temperatures by adjusting three of its factors; (a) the volume property of pure water, (b) the number of “free” water molecules per unit volume of solution, “N{sub f},” and (c) the “t” factor expressing the cooperative structural relaxation time of pure water at given temperatures. Adequate information on the volume property of pure water at different temperatures is available in the literature. However, as little information on the relative densities of inorganic and organic solutions, respectively, at varying temperatures needed to calculate N{sub f} was available, provisional equations were formulated to approximate values. Those values together with tentative t values for different temperatures chosen from values calculated by different workers were substituted into the authors’ equation to demonstrate how osmotic potentials could be estimated over temperatures up to and beyond bodily temperatures. Results: The provisional equations formulated to calculate N{sub f}, the number of free water molecules per unit volume of inorganic and organic solute solutions, respectively, over wide concentration ranges compared well with the calculations of N{sub f

Osmotic potential calculations of inorganic and organic aqueous solutions over wide solute concentration levels and temperatures

International Nuclear Information System (INIS)

Cochrane, T. T.; Cochrane, T. A.

2016-01-01

Purpose: To demonstrate that the authors’ new “aqueous solution vs pure water” equation to calculate osmotic potential may be used to calculate the osmotic potentials of inorganic and organic aqueous solutions over wide ranges of solute concentrations and temperatures. Currently, the osmotic potentials of solutions used for medical purposes are calculated from equations based on the thermodynamics of the gas laws which are only accurate at low temperature and solute concentration levels. Some solutions used in medicine may need their osmotic potentials calculated more accurately to take into account solute concentrations and temperatures. Methods: The authors experimented with their new equation for calculating the osmotic potentials of inorganic and organic aqueous solutions up to and beyond body temperatures by adjusting three of its factors; (a) the volume property of pure water, (b) the number of “free” water molecules per unit volume of solution, “N f ,” and (c) the “t” factor expressing the cooperative structural relaxation time of pure water at given temperatures. Adequate information on the volume property of pure water at different temperatures is available in the literature. However, as little information on the relative densities of inorganic and organic solutions, respectively, at varying temperatures needed to calculate N f was available, provisional equations were formulated to approximate values. Those values together with tentative t values for different temperatures chosen from values calculated by different workers were substituted into the authors’ equation to demonstrate how osmotic potentials could be estimated over temperatures up to and beyond bodily temperatures. Results: The provisional equations formulated to calculate N f , the number of free water molecules per unit volume of inorganic and organic solute solutions, respectively, over wide concentration ranges compared well with the calculations of N f using recorded

Quenching of acridine orange fluorescence by salts in aqueous solutions: Effects of aggregation and charge transfer

Energy Technology Data Exchange (ETDEWEB)

Amado, A.M. [Departamento de Física, FFCLRP, USP (Brazil); Ramos, A.P. [Departamento de Química, FFCLRP, USP (Brazil); Silva, E.R. [Departamento de Física, FFCLRP, USP (Brazil); Borissevitch, I.E., E-mail: iouribor@usp.br [Departamento de Física, FFCLRP, USP (Brazil)

2016-10-15

Acridine orange (AO) is widely applied in biology and medicine as a fluorescence probe, an intracellular pH indicator, and a photosensitizer in photodynamic therapy due to its adequate spectroscopic characteristics and high affinity to biological structures. Being introduced in an organism, AO is dispersed in blood plasma characterized by high ionic strength (ca. 0.36 M in humans). We have investigated the effect of ionic strength upon AO spectral characteristics and fluorescence quenching. The effect of pH on these characteristics was also tested. Salts quench AO fluorescence, the quenching constant (k{sub q}) increasing with the AO concentration. Salts stimulate AO aggregation, the process depending weakly on the salt origin. On the other hand, k{sub q} does depend on the salt anion origin, increasing as the anion oxidation potential decreases, and is virtually independent of the cation origin. This means that at least two different mechanisms of the AO fluorescence quenching by salts exist: fluorescence intensity decrease due to AO aggregation and quenching by partial electron transfer from salt anion to AO molecule in its singlet excited state (the exciplex formation).

Coalescence of organic solutions in acid and metal extraction by tri-alkylamines

International Nuclear Information System (INIS)

Blain, J.

1970-01-01

The formation of two layers with tri-alkylammonium salts solutions in low polarity diluents could be explained on the basis of settling of micelles. Light scattering and viscosity measurements reveal that micelles size increases rather sharply before coalescence. The existence of micelles in the solution has been confirmed by ultracentrifuge experiments. The behaviour of these solutions, in general, is similar to that of colloidal soap solutions. The various parameters which promote third phase formation are: anion size in the order of Cl - ∼ Br - 3 4 - ; extraction of excess acid; metal cation size in the order of UO 2 ++ 4+ ∼ Th 4+ ; decreasing in the length of the n-alkyl chain in the alkyl-ammonium salts; decreasing in diluent polarity. The above phenomenon could be explained on the basis of the affinity between alkylammonium salts and organic solvent. The composition of the three phases is independent of the initial amine concentration for a fixed acid and metal concentration. This has been verified experimentally and is in conformity with phase rule. (author) [fr

Effets of Silver Salt Concentrations on Green Synthesis of Silver Nanoparticles Using the Plant Nigella Saliva

Directory of Open Access Journals (Sweden)

M.R. Saeri

2016-03-01

Full Text Available Bio-inspired silver nanoparticles were synthesized with the aid of a novel method, using leaves of the plant Nigella sativa. After drying the leaves in air, they were first sweltered in boiling distilled water and the liquid was filtered subsequently. The result was the brothused to reduce solutions including various concentrations of silver nitrate in a proper amount of pH. The displayed UV–visible spectra identified formation of silver nanoparticles whenever the colorless initial acclimated mixture turned brown. The centrifuged powder samples were examined using X-ray diffraction (XRD, Fourier transform infrared spectroscopy (FTIR, scanning electron microscopy (FESEM and energy dispersive X-ray diffraction analysis (EDX methods. The results clearly revealed that the final particles of precipitated powder are high purity agglomerates of silver nanoparticles. Besides, the effects of various amounts of the silver salt on particle size of nano silver were studied, using a particle size analyzer. FTIR results also indicated the role of different functional groups in the synthetic process.

Simple electrolyte solutions: Comparison of DRISM and molecular dynamics results for alkali halide solutions

Science.gov (United States)

Joung, In Suk; Luchko, Tyler; Case, David A.

2013-01-01

Using the dielectrically consistent reference interaction site model (DRISM) of molecular solvation, we have calculated structural and thermodynamic information of alkali-halide salts in aqueous solution, as a function of salt concentration. The impact of varying the closure relation used with DRISM is investigated using the partial series expansion of order-n (PSE-n) family of closures, which includes the commonly used hypernetted-chain equation (HNC) and Kovalenko-Hirata closures. Results are compared to explicit molecular dynamics (MD) simulations, using the same force fields, and to experiment. The mean activity coefficients of ions predicted by DRISM agree well with experimental values at concentrations below 0.5 m, especially when using the HNC closure. As individual ion activities (and the corresponding solvation free energies) are not known from experiment, only DRISM and MD results are directly compared and found to have reasonably good agreement. The activity of water directly estimated from DRISM is nearly consistent with values derived from the DRISM ion activities and the Gibbs-Duhem equation, but the changes in the computed pressure as a function of salt concentration dominate these comparisons. Good agreement with experiment is obtained if these pressure changes are ignored. Radial distribution functions of NaCl solution at three concentrations were compared between DRISM and MD simulations. DRISM shows comparable water distribution around the cation, but water structures around the anion deviate from the MD results; this may also be related to the high pressure of the system. Despite some problems, DRISM-PSE-n is an effective tool for investigating thermodynamic properties of simple electrolytes. PMID:23387564

Strategies of two tropical woody species to tolerate salt stress

Directory of Open Access Journals (Sweden)

Bruno Melo Lustosa

2017-03-01

Full Text Available This study aimed to evaluate the leaf primary metabolism in two woody species, Sterculia foetida and Bombacopsis glabra. Both species have seeds rich in oil and they are largely found in regions with irregularities in water availability. Seedlings were grown in a greenhouse from seeds. At 140 days after emergence, 50% of the plants were subjected to salt stress for 23 days, daily receiving 100 mM of NaCl solution. In both species, leaf stomata conductance and water potential decreased quickly under salt stress. The two species showed different strategies in photosynthetic pigment concentration and components of nitrogen metabolism. S. foetida kept the pigment concentration unchanged after 23 days of stress, while B. glabra increased concentration of chlorophyll a and carotenoids. S. foetida showed a high leaf concentration of K+ in stressed plants and a Na+/K+ ratio without differences when compared to control. Thus, S. foetida presented a better ionic balance, while B. glabra invested in photoprotection. Therefore, both species present potential to be planted in Brazilian Northeast, where water deficit and salt stress are challenging for annual crops.

IODINE CONCENTRATION IN SALT AT HOUSEHOLD AND RETAIL ...

African Journals Online (AJOL)

hi-tech

2003-10-10

Oct 10, 2003 ... of shop salt samples have iodine levels below the minimum standard set by the Quality and. Standard Authority of Ethiopia. ... process towards meeting the goal of IDD elimination. Universal salt iodization (USI) is .... study populations was Oromo accounting for 155(51.8%) and 10(30.3%) in the household ...

Detection of salt bridges to lysines in solution in barnase

DEFF Research Database (Denmark)

Hansen, Poul Erik; Williamson, Michael P.; Hounslow, Andrea M.

2013-01-01

We show that salt bridges involving lysines can be detected by deuterium isotope effects on NMR chemical shifts of the sidechain amine. Lys27 in the ribonuclease barnase is salt bridged, and mutation of Arg69 to Lys retains a partially buried salt bridge. The salt bridges are functionally important....

The degree of doubly charged cation binding in solutions of (co)polymers of 2-acrylamido-2-methylpropanesulfonic acid salts

International Nuclear Information System (INIS)

Kurenkov, V.F.; Kolesnikova, I.Yu.; Antonovich, O.A.

2002-01-01

The degree of binding the ions of the alkaline-earth metals (M = Mg, Ca, Sr, Ba) by the polysulfate anions in the aqueous solutions of the polymers of the 2-acrylamido-2-methylpropanesulfonic acid (N-AMS) salts and their binary copolymers with the acrylamide (AA) and N-vinylpyrrolidone (VP) is quantitatively evaluated through the Terayama and Wall viscosimetric method. It is established, that the degree of binding decreases in the Sr>Ca>Mg sequence for the N-AMS polymer salts and in the reverse sequence (Mg>Ca>Sr(Ba)) for the binary copolymers of the N-AMS salts with AA and VP [ru

Effect of temperature and salting-out agents on the sorption of nitrophenols from aqueous solutions

Directory of Open Access Journals (Sweden)

E. V. Churilina

2013-01-01

Full Text Available Sorption of nitrophenols from aqueous media by сrosslinked N-vinylpyrrolidone-based polymer in static conditions are studied depending on the pH of the solution and the nature of the nitrophenols. It has been established that a temperature and the introduction of salting-out agents influence on the sorption of nitrophenols.

Antimicrobial activity of essential oils and fruits supplement in reduced nitrite salts condition

Directory of Open Access Journals (Sweden)

Vujadinović Dragan P.

2017-01-01

Full Text Available Because of the growing negative perception of consumers related to the use of meat products produced by conventional curing methods, organic and natural products are increasingly accepted by consumers. Such products contain a large number of natural products derived from plants, spices, as well as their derivatives in form of essential oils, extracts, concentrates, and so on. These derivatives contain large number of active substances which are known to inhibit the metabolic processes of bacteria, yeasts and molds. Therefore, the goal of this paper was to investigate the synergistic antimicrobial activity of the models with a reduced presence of nitrite salt in aqueous solution, emulsions of essential oils in varying concentrations in vivo via antibiogram tests on pathogenic microorganisms. The effect of the six model groups was analyzed. Two groups were fruit powder solutions in concentrations of 0.2% to 1.2% (Acerola powder and fruit powder mix, while the other four groups were models of aqueous emulsion of essential oil in concentrations ranging from 0.05% to 1.2% (tea tree, clove, oregano, and cinnamon essential oils. In all models reduced amount of the sodium salt of 1.80%, 0.0075% nitrite salt and the liquid derivative as a natural source of the nitrate salt of 3% were used. Antibiogram tests were performed on five pathogenic bacteria (C. perfringens, E. coli, S. enterica, L. monocytogenes, and S. aureus. All antibiogram tests were performed according to Kirby-Bauer disk diffusion protocol. Results of antibiograms showed that without the presence of additional antimicrobial agents, in model systems with reduced content of salts, inhibition zones were not detected. Additionally, models with essential oils of tea tree oil and oregano had the widest inhibition zone diameters, ranging from 17.76±0.48mm for E. coli up to 42.50±0.13mm for S. aureus.

Mixtures of lecithin and bile salt can form highly viscous wormlike micellar solutions in water.

Science.gov (United States)

Cheng, Chih-Yang; Oh, Hyuntaek; Wang, Ting-Yu; Raghavan, Srinivasa R; Tung, Shih-Huang

2014-09-02

The self-assembly of biological surfactants in water is an important topic for study because of its relevance to physiological processes. Two common types of biosurfactants are lecithin (phosphatidylcholine) and bile salts, which are both present in bile and involved in digestion. Previous studies on lecithin-bile salt mixtures have reported the formation of short, rodlike micelles. Here, we show that lecithin-bile salt micelles can be further induced to grow into long, flexible wormlike structures. The formation of long worms and their resultant entanglement into transient networks is reflected in the rheology: the fluids become viscoelastic and exhibit Maxwellian behavior, and their zero-shear viscosity can be up to a 1000-fold higher than that of water. The presence of worms is further confirmed by data from small-angle neutron and X-ray scattering and from cryo-transmission electron microscopy (cryo-TEM). We find that micellar growth peaks at a specific molar ratio (near equimolar) of bile salt:lecithin, which suggests a strong binding interaction between the two species. In addition, micellar growth also requires a sufficient concentration of background electrolyte such as NaCl or sodium citrate that serves to screen the electrostatic repulsion of the amphiphiles and to "salt out" the amphiphiles. We postulate a mechanism based on changes in the molecular geometry caused by bile salts and electrolytes to explain the micellar growth.

Pluronic®-bile salt mixed micelles.

Science.gov (United States)

Patel, Vijay; Ray, Debes; Bahadur, Anita; Ma, Junhe; Aswal, V K; Bahadur, Pratap

2018-06-01

The present study was aimed to examine the interaction of two bile salts viz. sodium cholate (NaC) and sodium deoxycholate (NaDC) with three ethylene polyoxide-polypropylene polyoxide (PEO-PPO-PEO) triblock copolymers with similar PPO but varying PEO micelles with a focus on the effect of pH on mixed micelles. Mixed micelles of moderately hydrophobic Pluronic ® P123 were examined in the presence of two bile salts and compared with those from very hydrophobic L121 and very hydrophilic F127. Both the bile salts increase the cloud point (CP) of copolymer solution and decreased apparent micelle hydrodynamic diameter (D h ). SANS study revealed that P123 forms small spherical micelles showing a decrease in size on progressive addition of bile salts. The negatively charged mixed micelles contained fewer P123 molecules but progressively rich in bile salt. NaDC being more hydrophobic displays more pronounced effect than NaC. Interestingly, NaC shows micellar growth in acidic media which has been attributed to the formation of bile acids by protonation of carboxylate ion and subsequent solubilization. In contrast, NaDC showed phase separation at higher concentration. Nuclear Overhauser effect spectroscopy (NOESY) experiments provided information on interaction and location of bile salts in micelles. Results are discussed in terms of hydrophobicity of bile salts and Pluronics ® and the site of bile salt in polymer micelles. Proposed molecular interactions are useful to understand more about bile salts which play important role in physiological processes. Copyright © 2018 Elsevier B.V. All rights reserved.

Potential and problems of an aqueous lithium salt solution blanket for NET

International Nuclear Information System (INIS)

Kuechle, M.; Bojarsky, E.; Dorner, S.; Fischer, U.; Reimann, J.; Reiser, H.

1987-07-01

The report describes design studies on a water cooled in-vessel shield blanket for NET and its modification into an aqueous lithium salt blanket. The shield blankets are exchangable against breeding blankets and fulfill their shielding and heat removal functions. Emphasis is on simplicity and reliability. The water cooled shield is a large steel container in the shape of the blanket segment which is filled by water and containes a grid structure of poloidally arranged steel plates. The water flows several times in poloidal direction through the channels formed by the steel plates and is thereby heated up from 40degC to 70degC. When the water is replaced by an aqueous lithium salt solution the shield can be converted into a tritium breeding blanket without any design modification or invessel component replacement. When compared with other concepts this blanket has the advantage that the solution can replace water cooling also in the divertor and in segments dedicated to plasma heating and diagnostics, what increases the coverage considerably. Extensive three-dimensional neutronics calculations were done which, together with literature studies on candidate materials, corrosion, and tritium recovery led to a first assessment of the concept. There is an indication that no major corrosion problems are to be expected in the low temperature region envisaged. Tritium recovery capital costs were estimated to be in the 20 MECU to 50 MECU range and tritium breeding ratio is comparable to the best breeding blanket. (orig./GG) [de

Evanescent Wave Absorption Based Fiber Sensor for Measuring Glucose Solution Concentration

Science.gov (United States)

Marzuki, Ahmad; Candra Pratiwi, Arni; Suryanti, Venty

2018-03-01

An optical fiber sensor based on evanescent wave absorption designed for measuring glucose solution consentration was proposed. The sensor was made to detect absorbance of various wavelength in the glucose solution. The sensing element was fabricated by side polishing of multimode polymer optical fiber to form a D-shape. The sensing element was immersed in different concentration of glucoce solution. As light propagated through the optical fiber, the evanescent wave interacted with the glucose solution. Light was absorbed by the glucose solution. The larger concentration the glucose solution has, the more the evanescent wave was absorbed in particular wavelenght. Here in this paper, light absorbtion as function of glucose concentration was measured as function of wavelength (the color of LED). We have shown that the proposed sensor can demonstrated an increase of light absorption as function of glucose concentration.

Automated assay of uranium solution concentration and enrichment

International Nuclear Information System (INIS)

Horley, E.C.; Gainer, K.; Hansen, W.J.; Kelley, T.A.; Parker, J.L.; Sampson, T.E.; Walton, G.; Jones, S.A.

1992-01-01

For the first time, the concentration and enrichment of uranium solutions can be measured in one step. We have developed a new instrument to automatically measure the concentration and enrichment of uranium solutions through the adaptation of a commercial robot. Two identical solution enrichment systems are being installed in the Portsmouth Gaseous Diffusion Plant. These automated systems will reduce radiation exposure to personnel and increase the reliability and repeatability of the measurements. Each robotic system can process up to 40 batch and 8 priority samples in an unattended mode. Both passive gamma-ray and x-ray fluorescence (XRF) analyses are performed to determine total uranium concentration and 235 U enrichment. Coded samples are read by a bar-code reader to determine measurement requirements, then assayed by either or both of the gamma-ray and XRF instruments. The robot moves the sample containers and operates all shield doors and shutters, reducing hardware complexity. If the robots is out of service, an operator can manually perform all operations

Distillation Separation of Hydrofluoric Acid and Nitric Acid from Acid Waste Using the Salt Effect on Vapor-Liquid Equilibrium

Science.gov (United States)

Yamamoto, Hideki; Sumoge, Iwao

2011-03-01

This study presents the distillation separation of hydrofluoric acid with use of the salt effect on the vapor-liquid equilibrium for acid aqueous solutions and acid mixtures. The vapor-liquid equilibrium of hydrofluoric acid + salt systems (fluorite, potassium nitrate, cesium nitrate) was measured using an apparatus made of perfluoro alkylvinylether. Cesium nitrate showed a salting-out effect on the vapor-liquid equilibrium of the hydrofluoric acid-water system. Fluorite and potassium nitrate showed a salting-in effect on the hydrofluoric acid-water system. Separation of hydrofluoric acid from an acid mixture containing nitric acid and hydrofluoric acid was tested by the simple distillation treatment using the salt effect of cesium nitrate (45 mass%). An acid mixture of nitric acid (5.0 mol · dm-3) and hydrofluoric acid (5.0 mol · dm-3) was prepared as a sample solution for distillation tests. The concentration of nitric acid in the first distillate decreased from 5.0 mol · dm-3 to 1.13 mol · dm-3, and the concentration of hydrofluoric acid increased to 5.41 mol · dm-3. This first distillate was further distilled without the addition of salt. The concentrations of hydrofluoric acid and nitric acid in the second distillate were 7.21 mol · dm-3 and 0.46 mol · dm-3, respectively. It was thus found that the salt effect on vapor-liquid equilibrium of acid mixtures was effective for the recycling of acids from acid mixture wastes.

Acute effects of road salts and associated cyanide compounds on the early life stages of the unionid mussel Villosa iris.

Science.gov (United States)

Pandolfo, Tamara J; Cope, W Gregory; Young, George B; Jones, Jess W; Hua, Dan; Lingenfelser, Susan F

2012-08-01

The toxicity of cyanide to the early life stages of freshwater mussels (order Unionida) has remained unexplored. Cyanide is known to be acutely toxic to other aquatic organisms. Cyanide-containing compounds, such as sodium ferrocyanide and ferric ferrocyanide, are commonly added to road deicing salts as anticaking agents. The purpose of the present study was to assess the acute toxicity of three cyanide compounds (sodium cyanide, sodium ferrocyanide, and ferric ferrocyanide), two road salts containing cyanide anticaking agents (Morton and Cargill brands), a brine deicing solution (Liquidow brand), and a reference salt (sodium chloride) on glochidia (larvae) and juveniles of the freshwater mussel Villosa iris. Sodium ferrocyanide and ferric ferrocyanide were not acutely toxic to glochidia and juvenile mussels at concentrations up to 1,000 mg/L and 100 mg/L, respectively. Lowest observed effect concentrations (LOECs) for these two chemicals ranged from 10 to >1,000 mg/L. Sodium cyanide was acutely toxic to juvenile mussels, with a 96-h median effective concentration (EC50) of 1.10 mg/L, although glochidia tolerated concentrations up to 10 mg/L. The EC50s for sodium chloride, Liquidow brine, Morton road salt, and Cargill road salt were not significantly different for tests within the same life stage and test duration (range, 1.66-4.92 g/L). These results indicate that cyanide-containing anticaking agents do not exacerbate the toxicity of road salts, but that the use of road salts and brine solutions for deicing or dust control on roads may warrant further investigation. Copyright © 2012 SETAC.

Cryoprotection properties of salts of organic acids: a case study for a tetragonal crystal of HEW lysozyme.

Science.gov (United States)

Bujacz, Grzegorz; Wrzesniewska, Blanka; Bujacz, Anna

2010-07-01

Currently, the great majority of the data that are used for solving macromolecular structures by X-ray crystallography are collected at cryogenic temperatures. Selection of a suitable cryoprotectant, which ensures crystal stability at low temperatures, is critical for the success of a particular diffraction experiment. The effectiveness of salts of organic acids as potential cryoprotective agents is presented in the following work. Sodium formate, acetate, malonate and citrate were tested, as were sodium potassium tartrate and acetate in the form of potassium and ammonium salts. For each salt investigated, the minimal concentration that was required for successful cryoprotection was determined over the pH range 4.5-9.5. The cryoprotective ability of these organic salts depends upon the number of carboxylic groups; the lowest concentration required for cryoprotection was observed at neutral pH. Case-study experiments conducted using the tetragonal form of hen egg-white lysozyme (HEWL) confirmed that salts of organic acids can successfully act as cryoprotective agents of protein crystals grown from high concentrations of inorganic salts. When crystals are grown from solutions containing a sufficient concentration of organic acid salts no additional cryoprotection is needed as the crystals can safely be frozen directly from the crystallizing buffers.

Salt tolerance of physalis during germination and seedling growth

International Nuclear Information System (INIS)

Yildirim, E.; Karlidag, H.

2011-01-01

The study was conducted to evaluate the effect of NaCl salinity on germination and emergence of Physalis ixocarpa and Physalis peruviana. Seeds of P. ixocarpa and P. peruviana were germinated by the use of 0, 30, 60, 90, 120 and 180 mM NaCl solutions in petri dishes. Final germination percentage (FGP) decreased with the increase in NaCl concentration. Both species germinated at the ranges of salinity. P. peruviana gave the greater germination percentages under salt stress than P. ixocarpa. NaCl salinity at different concentrations adversely affected germination rates. For seedling growth, seeds of both species were sown at 10 mm depth in plastic trays filled with peat to determine final emergence percentage (FEP). The trays were irrigated manually to saturation every day with 0, 30, 60, 90, 120, 150 or 180 mM NaCl solutions to maintain the level of salinity. Salinity affected seed emergence and seedlings growth more than seed germination. The study showed that no emergence of Physalis was observed at 90, 120 and 180 mM NaCl salinity. Fresh and dry weights of normal seedlings were also evaluated. Salt stress significantly decreased the plant fresh and dry weight of both species. Based on the results of the experiment, it can be concluded that seedling emergence and growth is more sensitive to salt stress than seed germination in Physalis. (author)

Geochemistry of great Salt Lake, Utah II: Pleistocene-Holocene evolution

Science.gov (United States)

Spencer, R.J.; Eugster, H.P.; Jones, B.F.

1985-01-01

Sedimentologic and biostratigraphic evidence is used to develop a geochemical model for Great Salt Lake, Utah, extending back some 30,000 yrs. B.P. Hydrologie conditions as defined by the water budget equation are characterized by a lake initially at a low, saline stage, rising by about 17,000 yrs. B.P. to fresh water basin-full conditions (Bonneville level) and then, after about 15,000 yrs. B.P., dropping rapidly to a saline stage again, as exemplified by the present situation. Inflow composition has changed through time in response to the hydrologie history. During fresh-water periods high discharge inflow is dominated by calcium bicarbonate-type river waters; during saline stages, low discharge, NaCl-rich hydrothermal springs are significant solute sources. This evolution in lake composition to NaCl domination is illustrated by the massive mirabilite deposition, free of halite, following the rapid drawdown until about 8,000 years ago, while historic droughts have yielded principally halite. Hydrologic history can be combined with inferred inflow composition to derive concentration curves with time for each major solute in the lake. Calcium concentrations before the drawdown were controlled by calcite solubility, and afterwards by aragonite. Significant amounts of solutes are removed from the lake by diffusion into the sediments. Na+, Cl- and SO42- are also involved in salt precipitation. By including pore fluid data, a surprisingly good fit has been obtained between solute input over the time period considered and the amounts actually found in lake brines, pore fluids, salt beds and sediments. Excess amounts are present for calcium, carbonate and silica, indicating detrital input. ?? 1985.

Sorption of cesium on montmorillonite and effect of salt concentration

International Nuclear Information System (INIS)

Atun, G.; Bilgin, B.; Mardinli, A.

1996-01-01

The sorption behavior of cesium on montmorillonite type[e clay was studied by using radioactivity measurements. Concentrations of Cs + ions ranged from 10 -6 to 10 -2 M. Cesium retention reduced with increasing salt concentration which was varied between 10 -4 and 10 -1 M. Selectivity coefficients K CsNa for the exchange between Cs and Na were calculated for different equivalent fractions of Cs on the solid phase. Using the K CsNa values, free energy change was found to be 7.8 kJ/mol. The data could be fitted to a Freundlich isotherm, and empirical Freundlich parameters enabled the generation of a site distribution function. By fitting the data to the Dubinin-Radushkevich (D-R) isotherm, a mean energy of sorption of 8.6kJ/mole was calculated which corresponds to the energy of ion exchange reactions. The values of energy changes calculated by using two different methods were in good agreement. (author)

The extraction of lanthanides and americium by benzyldiakylamines and benzyltrialkylammonium nitrates from the nitrate solutions; structure and aggregation of their salts

International Nuclear Information System (INIS)

Jedinakova, V.; Zilkova, J.; Dvorak, Z.; Vojtiskova, M.

1982-01-01

Benzyldialkylamine and benzyltrialkylammonium nitrates were used for the extraction of lanthanides and americium from aqueous nitrate solutions. The dependence of the extraction performance for Ln(III) and Am(III) on the concentration of nitric acid, the kind and concentration of salting-out agents in the aqueous phase, and the kind of solvent were investigated. The extraction of Am(III) is compared with the extraction of lanthanides. The difference in distribution coefficients for lanthanides and americium can be utilized for the separation of lanthanides and americium. Using vapor phase osmometry and cryoscopy the association of these compounds was measured at 5.5deg, 25deg and 37deg C, allowing rough estimates of ΔH and ΔS for the formation of the aggregates, monomers in the case of benzyldiethylamine, benzyldibutylamine, benzyldihexylamine and benzyldioctylamine, tetramers for the benzyldibutylamine nitrate and tetramers for benzyldimethyldodecylammonium nitrate. (author)

Plutonium solution in concentration range from 8 to 17 G/liter

Energy Technology Data Exchange (ETDEWEB)

Rothe, R.E.

1997-06-01

This paper very briefly discusses the need for a fundamental criticality study of low concentrations of plutonium solutions. Examples of the occurrence of such solutions, which are characteristic of waste, are cited. Due to the prevalence of decontaminating and decommissioning activities, low concentration solutions are expected to become an important concern. Technical deficiencies in previous calculations are also discussed as a reason for performing low concentration criticality studies. 3 refs.

Plutonium solution in concentration range from 8 to 17 G/liter

International Nuclear Information System (INIS)

Rothe, R.E.

1997-01-01

This paper very briefly discusses the need for a fundamental criticality study of low concentrations of plutonium solutions. Examples of the occurrence of such solutions, which are characteristic of waste, are cited. Due to the prevalence of decontaminating and decommissioning activities, low concentration solutions are expected to become an important concern. Technical deficiencies in previous calculations are also discussed as a reason for performing low concentration criticality studies. 3 refs

Radiolysis of concentrated nitric acid solutions

International Nuclear Information System (INIS)

Nagaishi, R.; Jiang, P.Y.; Katsumura, Y.; Domae, M.; Ishigure, K.

1995-01-01

A study on electron pulse- and 60 Co γ-radiolysis of concentrated nitric acid and nitrate solutions has been carried out to elucidate the radiation induced reactions taking place in the solutions. Dissociation into NO 2 - and O( 3 P) was proposed as a direct action of the radiation on nitrate and gave the G-values were dependent on the chemical forms of nitrate: g s2 (-NO 3 - )=1.6 and g s2 (-HNO 3 )=2.2 (molecules/100eV). Based on the experimental yields of HNO 2 and reduced Ce IV , the primary yields of radiolysis products of water, g w , were evaluated to clarify the effects of nitrate on spur reactions of water in various nitrate solutions. (author)

Crystallization of DNA fragments from water-salt solutions, containing 2-methylpentane-2,3-diol.

Science.gov (United States)

Osica, V D; Sukharevsky, B Y; Vasilchenko, V N; Verkin, B I; Polyvtsev, O F

1976-09-01

Fragments of calf thymus DNA have been crystallized by precipitation from water-salt solutions, containing 2-methylpentane-2,3-diol (MPD). DNA crystals usually take the form either of spherulites up to 100 mu in diameter or of needles with the length up to 50 mu. No irreversible denaturation of DNA occurs during the crystallization process. X-ray diffraction from dense slurries of DNA crystals yields crystalline powder patterns.

Screening of salt-tolerance potential of some native forage grasses from the eastern part of Terai-Duar grasslands in India

Directory of Open Access Journals (Sweden)

Swarnendu Roy

2017-09-01

Full Text Available The salt tolerance of 12 native forage grasses from the eastern part of Terai-Duar grasslands was assessed using a rapid method of leaf disc senescence bioassay. Samples of these grasses were grown in untreated water as well as 100 and 200 mM NaCl solutions for periods of 3, 6 and 9 days. Discs of fresh leaf were then placed in untreated water as well as in 100 and 200 mM NaCl solutions for 96 hours. Quantitative effects were measured as the effects on chlorophyll concentration in leaves in response to exposure to the varying solutions. From these results, the salt sensitivity index (SSI of the individual grasses was determined. The SSI values indicated that Imperata cylindrica, Digitaria ciliaris and Cynodon dactylon were most salt-tolerant of all grasses tested. Further characterization of the grasses was done by observing the changes in 6 biomarkers for salinity tolerance: relative water content, total sugar concentration, proline concentration, electrolyte leakage, membrane lipid peroxidation and H2O2 concentration following exposure to 100 and 200 mM NaCl concentrations for 3, 6 and 9 days. Finally, hierarchical cluster analysis using the software CLUSTER 3.0 was used to represent the inter-relations among the physiological parameters and to group the grasses on the basis of their salinity tolerance. The overall results indicated that Imperata cylindrica, Eragrostis amabilis, Cynodon dactylon and Digitaria ciliaris were potentially salt-tolerant grasses and should be planted on saline areas to verify our results. On the other hand, Axonopus compressus, Chrysopogon aciculatus, Oplismenus burmanni and Thysanolaena latifolia were found to be highly salt-sensitive and would be unsuitable for use in saline areas. 

Mechanism of pitting corrosion prevention by nitrite in carbon steel exposed to dilute salt solutions. 1998 annual progress report

International Nuclear Information System (INIS)

Zapp, P.E.; Zee, J. van.

1998-01-01

'The overall goal of this project is to develop a fundamental understanding of the role of nitrite in preventing the breakdown of protective oxide(s) on carbon steel and the onset of pitting. Pitting corrosion of carbon steel exposed to dilute alkaline salt solutions can be induced by nitrate, sulfate, and chloride ions and is prevented by sufficient concentration of nitrite. A significant example of this material/electrolyte system is the storage and processing of DOE''s high-level radioactive liquid waste in carbon steel tanks. Added nitrite in the waste has a considerable downstream impact on the immobilization of the waste in a stable glass form. Waste tank integrity and glass production efficiency may benefit from the fundamental understanding of nitrite''s role in preventing pitting. This report summarizes progress after approximately six months of effort in this three-year EMSP project. Initial experimental and theoretical work has focused on the electrochemical behavior of carbon steel in simplified non-radioactive solutions that simulate complex dilute radioactive waste solutions. These solutions contain corrosion-inducing species such as nitrate and chloride and the corrosion-inhibiting nitrite at moderately alkaline pHs. The electrochemical behavior of interest here is that of the open-circuit potential of the steel specimen at equilibrium in the experimental electrolyte and the measures of the steel''s passivity and passivity breakdown.'

History and future of human cadaver preservation for surgical training: from formalin to saturated salt solution method.

Science.gov (United States)

Hayashi, Shogo; Naito, Munekazu; Kawata, Shinichi; Qu, Ning; Hatayama, Naoyuki; Hirai, Shuichi; Itoh, Masahiro

2016-01-01

Traditionally, surgical training meant on-the-job training with live patients in an operating room. However, due to advancing surgical techniques, such as minimally invasive surgery, and increasing safety demands during procedures, human cadavers have been used for surgical training. When considering the use of human cadavers for surgical training, one of the most important factors is their preservation. In this review, we summarize four preservation methods: fresh-frozen cadaver, formalin, Thiel's, and saturated salt solution methods. Fresh-frozen cadaver is currently the model that is closest to reality, but it also presents myriad problems, including the requirement of freezers for storage, limited work time because of rapid putrefaction, and risk of infection. Formalin is still used ubiquitously due to its low cost and wide availability, but it is not ideal because formaldehyde has an adverse health effect and formalin-embalmed cadavers do not exhibit many of the qualities of living organs. Thiel's method results in soft and flexible cadavers with almost natural colors, and Thiel-embalmed cadavers have been appraised widely in various medical disciplines. However, Thiel's method is relatively expensive and technically complicated. In addition, Thiel-embalmed cadavers have a limited dissection time. The saturated salt solution method is simple, carries a low risk of infection, and is relatively low cost. Although more research is needed, this method seems to be sufficiently useful for surgical training and has noteworthy features that expand the capability of clinical training. The saturated salt solution method will contribute to a wider use of cadavers for surgical training.

Textural improvement of salt-reduced Alaska pollack (Theragra chalcogramma) roe product by CaCl2.

Science.gov (United States)

Chen, Chaoping; Okazaki, Emiko; Osako, Kazufumi

2016-12-15

Salt-reduced Alaska pollack roe benefits public health by decreasing NaCl intake; however, it has a poor texture with low breaking strength. This study addresses the feasibility of NaCl reduction in salted roe products, with focusing on the improvement of breaking strength using CaCl2. Salted roe products were prepared by immersing Alaska pollack roe in either NaCl solutions (3.5, 7.0, 15.0, 20.0, and 25.0%) or 7.0% NaCl solutions with added CaCl2 (0.0, 0.5, 1.0, 2.0, and 3.0%). Breaking strength, moisture and salt contents, eggshell protein composition of the salted roe products, as well as total endogenous transglutaminase (TGase) activity in various NaCl and CaCl2 concentrations were analyzed. CaCl2 addition enhanced eggshell protein crosslinking and breaking strength of the salt-reduced roe products. An acyl transfer reaction catalyzed by calcium-dependent TGase may be responsible for the eggshell protein crosslinking and improved texture. Thus, we successfully developed a salt-reduced Alaska roe product using CaCl2. Copyright © 2016 Elsevier Ltd. All rights reserved.

A Wavefront Division Polarimeter for the Measurements of Solute Concentrations in Solutions

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Sergio Calixto

2017-12-01

Full Text Available Polarimeters are useful instruments that measure concentrations of optically active substances in a given solution. The conventional polarimetric principle consists of measuring the rotation angle of linearly polarized light. Here, we present a novel polarimeter based on the study of interference patterns. A Mach–Zehnder interferometer with linearly polarized light at the input is used. One beam passes through the liquid sample and the other is a reference beam. As the linearly polarized sample beam propagates through the optically active solution the vibration plane of the electric field will rotate. As a result, the visibility of the interference pattern at the interferometer output will decrease. Fringe contrast will be maximum when both beams present a polarization perpendicular to the plane of incidence. However, minimum visibility is obtained when, after propagation through the sample the polarization of the sample beam is oriented parallel to the plane of incidence. By using different solute concentrations, a calibration plot is obtained showing the behavior of visibility.

Influence of Proton and Salt Concentration on the Chromonic Liquid Crystal Phase Diagram of Disodium Cromoglycate Solutions: Prospects and Limitations of a Host for DNA Nanostructures.

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Zhang, Bingru; Kitzerow, Heinz-S

2016-03-31

Lyotropic chromonic liquid crystals have recently been suggested for use as a self-organized host for dispersing and aligning self-organized DNA origami nanostructures. However, an appropriate pH value and a suitable cation concentration are necessary to stabilize such nanostructures and to avoid unfolding of the DNA. The present study shows that the nematic and columnar liquid crystal phases appearing in aqueous solutions of disodium cromoglycate are robust against the replacement of deionized water by a neutral or alkaline buffer solution. However, disodium cromoglycate precipitates when an acidic buffer is used or when the concentration of magnesium cations exceeds a critical concentration of about 0.6-0.7 mmol/L.

Laboratory simulation of salt dissolution during waste removal

International Nuclear Information System (INIS)

Wiersma, B.J.; Parish, W.R.

1997-01-01

Laboratory experiments were performed to support the field demonstration of improved techniques for salt dissolution in waste tanks at the Savannah River Site. The tests were designed to investigate three density driven techniques for salt dissolution: (1) Drain-Add-Sit-Remove, (2) Modified Density Gradient, and (3) Continuous Salt Mining. Salt dissolution was observed to be a very rapid process as salt solutions with densities between 1.38-1.4 were frequently removed. Slower addition and removal rates and locating the outlet line at deeper levels below the top of the saltcake provided the best contact between the dissolution water and the saltcake. It was observed that dissolution with 1 M sodium hydroxide solution resulted in salt solutions that were within the current inhibitor requirements for the prevention of stress corrosion cracking. This result was independent of the density driven technique. However, if inhibited water (0.01 M sodium hydroxide and 0.011 M sodium nitrite) was utilized, the salt solutions were frequently outside the inhibitor requirements. Corrosion testing at conditions similar to the environments expected during waste removal was recommended

Rheological properties of concentrated solutions of carboxymethyl starch

Directory of Open Access Journals (Sweden)

Stojanović Željko

2003-01-01

Full Text Available Carboxymethyl starch was synthesized by the esterification of starch with monochloroacetic acid in ethanol as a reaction medium. Three samples of carboxymethyl starch having different degrees of substitution were prepared. The influence of temperature on the viscosity of concentrated carboxymethyl starch solutions, as well as the dynamic-mechanical properties of the concentrated solutions were investigated. The activation energy of viscous flow was determined and it was found that it decreased with increasing degree of substitution. The results of the dynamic-mechanical measurements showed that solutions of starch and carboxymethyl starches with higher degrees of substitution behave as gels. Values of the storage modulus in the rubbery plateau were used to calculate the molar masses between two points of physical crosslinking, the density of crosslinking and the distance between two points of crosslinking.

Evaluation of poly (aspartic acid sodium salt) as a draw solute for forward osmosis.

Science.gov (United States)

Gwak, Gimun; Jung, Bokyung; Han, Sungsoo; Hong, Seungkwan

2015-09-01

Poly (aspartic acid sodium salt) (PAspNa) was evaluated for its potential as a novel draw solute in forward osmosis (FO). The inherent advantages of PAspNa, such as good water solubility, high osmotic pressure, and nontoxicity, were first examined through a series of physicochemical analyses and atomic-scale molecular dynamics simulations. Then, lab-scale FO tests were performed to evaluate its suitability in practical processes. Compared to other conventional inorganic solutes, PAspNa showed comparable water flux but significantly lower reverse solute flux, demonstrating its suitability as a draw solute. Moreover, fouling experiments using synthetic wastewater as a feed solution demonstrated that PAspNa reversely flowed to the feed side reduced inorganic scaling on the membrane active layer. The recyclability of PAspNa was studied using both nanofiltration (NF) and membrane distillation (MD) processes, and the results exhibited its ease of recovery. This research reported the feasibility and applicability of FO-NF or FO-MD processes using PAspNa for wastewater reclamation and brackish water desalination. Copyright © 2015 Elsevier Ltd. All rights reserved.

SEPARATION OF METAL SALTS BY ADSORPTION

Science.gov (United States)

Gruen, D.M.

1959-01-20

It has been found that certain metal salts, particularly the halides of iron, cobalt, nickel, and the actinide metals, arc readily absorbed on aluminum oxide, while certain other salts, particularly rare earth metal halides, are not so absorbed. Use is made of this discovery to separate uranium from the rare earths. The metal salts are first dissolved in a molten mixture of alkali metal nitrates, e.g., the eutectic mixture of lithium nitrate and potassium nitrate, and then the molten salt solution is contacted with alumina, either by slurrying or by passing the salt solution through an absorption tower. The process is particularly valuable for the separation of actinides from lanthanum-group rare earths.