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Sample records for salt solution interfaces

  1. 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.

  2. 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

  3. Permeability of salt-crystal interfaces to brine

    International Nuclear Information System (INIS)

    Gilpatrick, L.O.; Baes, C.F. Jr.; Shor, A.J.; Canonico, C.M.

    1982-06-01

    To investigate the movement of brine along grain boundaries in polycrystalline salt, measurements have been made of the radial flow of brine through the interface between cylindrical salt crystals under axial stresses to 140 bar and temperatures to 80 0 C. For constant conditions, the total flow of brine showed a linear dependence on the logarithm of time, and the reciprocal permeability increased linearly with time. Loss of salt from the interface by pressure solution effects was more than enough to account for the decrease in the apparent thickness of the interface (i.e., that which may be estimated for an interface of the same permeability formed by plane parallel surfaces). This apparent thickness, initially as large as 10 μm, decreased to as little as 0.2 μm with exposure to stress and flowing brine. It decreased quickly with sudden increases in axial stress and usually increased, though not reversibly, with decreases in stress. The rate of increase in the reciprocal permeability with time was roughly proportional to the stress and to the square of the hydraulic pressure drop. Assuming similar apparent thicknesses for the grain boundaries in polycrystalline salt, permeabilities are predicted that are quite consistent with the low values reported for stressed core specimens

  4. 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

  5. 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

  6. 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.

  7. Solidification of salt solutions on a horizontal surface

    International Nuclear Information System (INIS)

    Braga, S.L.; Viskanta, R.

    1990-01-01

    The freezing of water-salt solutions on a horizontal wall is investigated experimentally and theoretically. The growth of the solid-liquid region is observed for NaCl - H sub(2)O and N H sub(4)Cl - H sub(2)O systems under different temperature and concentration conditions. A unidirectional mathematical model is used to predict the solidification process. The transport of heat is by diffusion, and convection is absent. The mass diffusion is neglected and the growth of crystal is governed by the transport of heat. In all experiments, the solution salt concentration is smaller than the eutectic composition, and the wall temperature is higher than the eutectic temperature. The predicted temperature and salt concentration profiles, as well as the interface position, are compared with experimental data. (author)

  8. 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

  9. 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

  10. Investigating effects of hypertonic saline solutions on lipid monolayers at the air-water interface

    KAUST Repository

    Nava Ocampo, Maria F.

    2017-05-01

    More than 70,000 people worldwide suffer from cystic fibrosis, a genetic disease characterized by chronic accumulation of mucus in patients’ lungs provoking bacterial infections, and leading to respiratory failure. An employed age-old treatment to prevent the symptoms of the disease is inhalation of hypertonic saline solution, NaCl at concentrations higher than in the human body (~150 mM). This procedure clears the mucus in the lungs, bringing relief to the patient. However, the biophysical mechanisms underlying this process are not entirely clear. We undertook a new experimental approach to understand the effects of sprayed saline solutions on model lung surfactants towards understanding the mechanisms of the treatment. The surface of lungs contains mainly 1,2-Dipalmitol-sn-glycero-3-phosphocoline (DPPC). As previously assumed by others, we considered that monolayer of DPPC at the air-water interface serves as model system for the lungs surface; we employed a Langmuir-Blodgett (LB) trough and PM-IRRAS to measure surface-specific infrared spectra of the surfactant monolayers and effects on the interfacial tensions. We investigated spraying hyper-saline solutions onto surfactant monolayers at the airwater interface in two parts: (i) validation of our methodology and techniques with stearic acid and (ii) experiments with DPPC monolayers at the air-water interface. Remarkably, when micro-droplets of NaCl were sprayed to the monolayer of stearic acid, we observed enhanced organization of the surfactant, interpreted from the intensities of the CH2 peaks in the surface-specific IR spectra. However, our results with DPPC monolayers didn’t show an effect with the salt added as aerosol, possibly indicating that the experimental methodology proposed is not adequate for the phenomena studied. In parallel, we mimicked respiratory mucous by preparing salt solutions containing 1% (wt%) agar and measured effects on their viscosities. Interestingly, we found that NaCl was much

  11. Experimental study of natural convection melting of ice in salt solutions

    International Nuclear Information System (INIS)

    Fang, L.J.; Cheung, F.B.; Linehan, J.H.; Pedersen, D.R.

    1984-01-01

    The solid-liquid interface morphology and the micro-physical process near the moving phase boundary during natural convection melting of a horizontal layer of ice by an overlying pool of salt solution were studied experimentally. A cathetometer which amplifies the interface region was used to measure the ice melting rate. Also measured were the temperature transients of the liquid pool. Within the temperature and the density ratio ranges explored, the ice melting rate was found to be very sensitive to the ratio of pool-to-ice melt density but independent of pool-to-ice temperature difference. By varying the density ratio, three different flow regimes and morphologies of the solid-liquid interface were observed, with melt streamers emanating from the crests of the wavy interface into the pool in all three cases. The measured wavelengths (spacing) between the streamers for four different pairs of materials were correlated with the density ratio and found to agree favorably with the predictions of Taylor instability theory

  12. 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

  13. 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.

  14. On NO3-H2O interactions in aqueous solutions and at interfaces

    International Nuclear Information System (INIS)

    Dang, Liem X.; Chang, Tsun-Mei; Roeselova, Martina; Garrett, Bruce C.; Tobias, Douglas J.

    2006-01-01

    Constrained molecular dynamics technique was employed to investigate the transport of a nitrate ion across the water liquid/vapor interface. We developed the nitrate ion-water polarizable potential capable of describing well the solvation properties of the hydrated nitrate ion. The computed free energy profile for the transfer of the nitrate ion across the air/water interface increases monotonically as the nitrate ion approaches the Gibbs dividing surface from the bulk liquid side. The computed density profiles of 1M KNO3 salt solution slab indicate that the nitrate and potassium ions are both found below the aqueous interface. Upon analyzing the results, we can conclude that the probability of finding the nitrate anion at the aqueous interface is quite small

  15. Americium separations from high salt solutions

    International Nuclear Information System (INIS)

    Barr, Mary E.; Jarvinen, Gordon D.; Schulte, Louis D.; Stark, Peter C.; Chamberlin, Rebecca M.; Abney, Kent D.; Ricketts, Thomas E.; Valdez, Yvette E.; Bartsch, Richard A.

    2000-01-01

    Americium (III) exhibits an unexpectedly high affinity for anion-exchange material from the high-salt evaporator bottoms solutions--an effect which has not been duplicated using simple salt solutions. Similar behavior is observed for its lanthanide homologue, Nd(III), in complex evaporator bottoms surrogate solutions. There appears to be no single controlling factor--acid concentration, total nitrate concentration or solution ionic strength--which accounts for the approximately 2-fold increase in retention of the trivalent ions from complex solutions relative to simple solutions. Calculation of species activities (i.e., water, proton and nitrate) in such concentrated mixed salt solutions is difficult and of questionable accuracy, but it is likely that the answer to forcing formation of anionic nitrate complexes of americium lies in the relative activities of water and nitrate. From a practical viewpoint, the modest americium removal needs (ca. 50--75%) from nitric acid evaporator bottoms allow sufficient latitude for the use of non-optimized conditions such as running existing columns filled with older, well-used Reillex HPQ. Newer materials, such as HPQ-100 and the experimental bifunctional resins, which exhibit higher distribution coefficients, would allow for either increased Am removal or the use of smaller columns. It is also of interest that one of the experimental neutral-donor solid-support extractants, DHDECMP, exhibits a similarly high level of americium (total alpha) removal from EV bottoms and is much less sensitive to total acid content than commercially-available material

  16. Salt Effect on Osmotic Pressure of Polyelectrolyte Solutions: Simulation Study

    Directory of Open Access Journals (Sweden)

    Jan-Michael Y. Carrillo

    2014-07-01

    Full Text Available Abstract: We present results of the hybrid Monte Carlo/molecular dynamics simulations of the osmotic pressure of salt solutions of polyelectrolytes. In our simulations, we used a coarse-grained representation of polyelectrolyte chains, counterions and salt ions. During simulation runs, we alternate Monte Carlo and molecular dynamics simulation steps. Monte Carlo steps were used to perform small ion exchange between simulation box containing salt ions (salt reservoir and simulation box with polyelectrolyte chains, counterions and salt ions (polyelectrolyte solution. This allowed us to model Donnan equilibrium and partitioning of salt and counterions across membrane impermeable to polyelectrolyte chains. Our simulations have shown that the main contribution to the system osmotic pressure is due to salt ions and osmotically active counterions. The fraction of the condensed (osmotically inactive counterions first increases with decreases in the solution ionic strength then it saturates. The reduced value of the system osmotic coefficient is a universal function of the ratio of the concentration of osmotically active counterions and salt concentration in salt reservoir. Simulation results are in a very good agreement with osmotic pressure measurements in sodium polystyrene sulfonate, DNA, polyacrylic acid, sodium polyanetholesulfonic acid, polyvinylbenzoic acid, and polydiallyldimethylammonium chloride solutions.

  17. 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 ...

  18. Interface Evolution During Transient Pressure Solution Creep

    Science.gov (United States)

    Dysthe, D. K.; Podladchikov, Y. Y.; Renard, F.; Jamtveit, B.; Feder, J.

    When aggregates of small grains are pressed together in the presence of small amounts of solvent the aggregate compacts and the grains tend to stick together. This hap- pens to salt and sugar in humid air, and to sediments when buried in the Earths crust. Stress concentration at the grain contacts cause local dissolution, diffusion of the dissolved material out of the interface and deposition on the less stressed faces of the grains{1}. This process, in geology known as pressure solution, plays a cen- tral role during compaction of sedimentary basins{1,2}, during tectonic deformation of the Earth's crust{3}, and in strengthening of active fault gouges following earth- quakes{4,5}. Experimental data on pressure solution has so far not been sufficiently accurate to understand the transient processes at the grain scale. Here we present ex- perimental evidence that pressure solution creep does not establish a steady state inter- face microstructure as previously thought. Conversely, cumulative creep strain and the characteristic size of interface microstructures grow as the cubic root of time. A sim- ilar transient phenomenon is known in metallurgy (Andrade creep) and is explained here using an analogy with spinodal dewetting. 1 Weyl, P. K., Pressure solution and the force of crystallization - a phenomenological theory. J. Geophys. Res., 64, 2001-2025 (1959). 2 Heald, M. T., Cementation of Simpson and St. Peter Sandstones in parts of Okla- homa, Arkansas and Missouri, J. Geol. Chicago, 14, 16-30 (1956). 3 Schwartz, S., Stöckert, B., Pressure solution in siliciclastic HP-LT metamorphic rocks constraints on the state of stress in deep levels of accretionary complexes. Tectonophysics, 255, 203-209 (1996). 4 Renard, F., Gratier, J.P., Jamtveit, B., Kinetics of crack-sealing, intergranular pres- sure solution, and compaction around active faults. J. Struct. Geol., 22, 1395-1407, (2000). 5 Miller, S. A., BenZion, Y., Burg, J. P.,A three-dimensional fluid-controlled earth

  19. 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.

  20. 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.

  1. [Determination of Chloride Salt Solution by NIR Spectroscopy].

    Science.gov (United States)

    Zhang, Bin; Chen, Jian-hong; Jiao, Ming-xing

    2015-07-01

    Determination of chloride salt solution by near infrared spectrum plays a very important role in Biomedicine. The near infrared spectrum analysis of Sodium chloride, potassium chloride, calcium chloride aqueous solution shows that the concentration change of chloride salt can affect hydrogen bond, resulting in the variation of near infrared spectrum of water. The temperature influence on NIR spectrum has been decreased by choosing reasonable wavelength range and the wavelength where the temperature effects are zero (isosbestic point). Chlorine salt prediction model was established based on partial least squares method and used for predicting the concentration of the chlorine ion. The impact on near infrared spectrum of the cation ionic radius, the number of ionic charge, the complex effect of ionic in water has also discussed in this article and the reason of every factor are analysed. Experimental results show that the temperature and concentration will affect the near-infrared spectrum of the solution, It is found that the effect of temperature plays the dominant role at low concentrations of chlorine salt; rather, the ionic dominates at high concentration. Chloride complexes are formed in aqueous solution, It has an effect on hydrogen bond of water combining with the cations in chlorine salt solution, Comparing different chloride solutions at the same concentration, the destruction effects of chloride complexes and catnions on the hydrogen bond of water increases in the sequences: CaCl2 >NaCl>KC. The modeling result shows that the determination coefficients (R2) = 99.97%, the root mean square error of cross validation (RM- SECV) = 4.51, and the residual prediction deviation (RPD) = 62.7, it meets the daily requirements of biochemical detection accuracy.

  2. 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

  3. 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)

  4. Solutal convection induced by dissolution. Influence on erosion dynamics and interface shaping.

    Science.gov (United States)

    Berhanu, Michael; Philippi, Julien; Cohen, Caroline; Derr, Julien; Courrech du Pont, Sylvain

    2017-04-01

    Rock fractures invaded by a water flow, are often subjected to dissolution, which let grow and evolve the initial fracture network, by evacuating the eroded minerals under a solute form. In the case of fast kinetic of dissolution, local erosion rate is set by the advection of the solute. The erosion velocity decreases indeed with the solute concentration at the interface and vanishes when this concentration reaches the saturation value. Even in absence of an imposed or external flow, advection can drive the dissolution, when buoyancy effects due to gravity induce a solutal convection flow, which controls the erosive dynamics and modifies the shape of the dissolving interface. Here, we investigate using model experiments with fast dissolving materials and numerical simulations in simplified situations, solutal convection induced by dissolution. Results are interpreted regarding a linear stability analysis of the corresponding solutal Rayleigh-Benard instability. A dissolving surface is suspended above a water height, initially at rest. In a first step, solute flux is transported through a growing diffusion layer. Then after an onset time, once the layer exceeds critical width, convection flow starts under the form of falling plumes. A dynamic equilibrium results in average from births and deaths of intermittent plumes, setting the size of the solute concentration boundary layer at the interface and thus the erosion velocity. Solutal convection can also induce a pattern on the dissolving interface. We show experimentally with suspended and inclined blocks of salt and sugar, that in a linear stage, the first wavelength of the dissolution pattern corresponds to the wavelength of the convection instability. Then pattern evolves to more complex shapes due to non-linear interactions between the flow and the eroded interface. More generally, we inquire what are the conditions to observe a such solutal convection instability in geological situations and if the properties of

  5. Problems of evaluating isotope analysis of concentrated salt solutions in potash mines

    International Nuclear Information System (INIS)

    Schmiedl, H.D.

    1980-01-01

    Three problems of quantitative evaluation of analytic D and 18 O isotope data of concentrated salt solutions are discussed: (1) Consideration of the influence of admixtures of hydrated salts in determining meteoric or marine water fractions in a concentrated salt solution, (2) analytic accuracy and detection limits in determining meteoric water in salt solutions, and (3) processes of isotopic exchange with reservoir rock and sample matrix

  6. Salt type and concentration affect the viscoelasticity of polyelectrolyte solutions

    Science.gov (United States)

    Turkoz, Emre; Perazzo, Antonio; Arnold, Craig B.; Stone, Howard A.

    2018-05-01

    The addition of small amounts of xanthan gum to water yields viscoelastic solutions. In this letter, we show that the viscoelasticity of aqueous xanthan gum solutions can be tuned by different types of salts. In particular, we find that the decrease in viscoelasticity not only depends, as is known, on the salt concentration, but also is affected by the counterion ionic radius and the valence of the salt.

  7. 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

  8. 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...

  9. 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)

  10. Magnetic coupling at perovskite and rock-salt structured interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Matvejeff, M., E-mail: mikko.matvejeff@picosun.com [Institute for Solid State Physics, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, 277-8581 Chiba (Japan); Department of Chemistry, Aalto University, Kemistintie 1, 02150 Espoo (Finland); Ahvenniemi, E. [Department of Chemistry, Aalto University, Kemistintie 1, 02150 Espoo (Finland); Takahashi, R.; Lippmaa, M. [Institute for Solid State Physics, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, 277-8581 Chiba (Japan)

    2015-10-05

    We study magnetic coupling between hole-doped manganite layers separated by either a perovskite or a rock-salt barrier of variable thickness. Both the type and the quality of the interface have a strong impact on the minimum critical barrier thickness where the manganite layers become magnetically decoupled. A rock-salt barrier layer only 1 unit cell (0.5 nm) thick remains insulating and is able to magnetically de-couple the electrode layers. The technique can therefore be used for developing high-performance planar oxide electronic devices such as magnetic tunnel junctions and quantum well structures that depend on magnetically and electronically sharp heterointerfaces.

  11. Thermophysical property characterization of aqueous amino acid salt solution containing serine

    International Nuclear Information System (INIS)

    Navarro, Shanille S.; Leron, Rhoda B.; Soriano, Allan N.; Li, Meng-Hui

    2014-01-01

    Highlights: • Thermophysical properties of aqueous potassium and sodium salt solutions of serine were studied. • Density, viscosity, refractive index and electrolytic conductivity of the solution were measured. • The concentrations of amino acid salt ranges from x 1 = 0.009 to 0.07. • The temperature range studied was (298.15 to 343.15) K. • The measured data were represented satisfactorily by using the applied correlations. - Abstract: Thermophysical property characterization of aqueous potassium and sodium salt solutions containing serine was conducted in this study; specifically the system’s density, refractive index, electrical conductivity, and viscosity. Measurements were obtained over a temperature range of (298.15 to 343.15) K and at normal atmospheric pressure. Composition range from x 1 = 0.009 to 0.07 for aqueous potassium and sodium salt solutions containing serine was used. The sensitivity of the system’s thermophysical properties on temperature and composition variation were discussed and correlated based on the equations proposed for room temperature ionic liquids. The density, viscosity, and refractive index measurements of the aqueous systems were found to decrease as the temperature increases at fixed concentration and the values increase as the salt concentration increases (water composition decreases) at fixed temperature. Whereas, a different trend was observed for the electrical conductivity data; at fixed concentration, the conductivity values increase as the temperature increases and at fixed temperature, its value generally increases as the salt concentration increases but only to a certain level (specific concentration) wherein the conductivity of the solution starts to decrease when the concentration of the salt is further increased. Calculation results show that the applied models were satisfactory in representing the measured properties in the aqueous amino acid salt solution containing serine

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. Reconciling estimates of the ratio of heat and salt fluxes at the ice-ocean interface

    Science.gov (United States)

    Keitzl, T.; Mellado, J. P.; Notz, D.

    2016-12-01

    The heat exchange between floating ice and the underlying ocean is determined by the interplay of diffusive fluxes directly at the ice-ocean interface and turbulent fluxes away from it. In this study, we examine this interplay through direct numerical simulations of free convection. Our results show that an estimation of the interface flux ratio based on direct measurements of the turbulent fluxes can be difficult because the flux ratio varies with depth. As an alternative, we present a consistent evaluation of the flux ratio based on the total heat and salt fluxes across the boundary layer. This approach allows us to reconcile previous estimates of the ice-ocean interface conditions. We find that the ratio of heat and salt fluxes directly at the interface is 83-100 rather than 33 as determined by previous turbulence measurements in the outer layer. This can cause errors in the estimated ice-ablation rate from field measurements of up to 40% if they are based on the three-equation formulation.

  17. The effects of soluble salts at the metal/paint interface: advances in knowledge

    OpenAIRE

    Fuente, Daniel de la; Chico, Belén; Morcillo, Manuel

    2006-01-01

    The presence of soluble salts (particularly sulphates and chlorides) at the metal/paint interface is known to have a detrimental effect on the integrity of most paint systems. Though this is a long-standing problem, it has recently come to receive greater attention from the protective coatings industry. International Standards Organization (ISO) has for some time been trying to develop a standard about guidance levels for water-soluble salt contamination before the application of paints and r...

  18. 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

  19. The Interface Between Fresh and Salt Groundwater in Horizontal Aquifers : The Dupuit–Forchheimer Approximation Revisited

    NARCIS (Netherlands)

    van Duijn, C. J.; Schotting, R. J.

    We analyze the motion of a sharp interface between fresh and salt groundwater in horizontal, confined aquifers of infinite extend. The analysis is based on earlier results of De Josselin de Jong (Proc Euromech 143:75–82, 1981). Parameterizing the height of the interface along the horizontal base of

  20. The interface between fresh and salt groundwater in horizontal aquifers : the Dupuit–Forchheimer approximation revisited

    NARCIS (Netherlands)

    van Duijn, C. J.; Schotting, R. J.

    2017-01-01

    We analyze the motion of a sharp interface between fresh and salt groundwater in horizontal, confined aquifers of infinite extend. The analysis is based on earlier results of De Josselin de Jong (Proc Euromech 143:75–82, 1981). Parameterizing the height of the interface along the horizontal base of

  1. Materials interface engineering for solution-processed photovoltaics.

    Science.gov (United States)

    Graetzel, Michael; Janssen, René A J; Mitzi, David B; Sargent, Edward H

    2012-08-16

    Advances in solar photovoltaics are urgently needed to increase the performance and reduce the cost of harvesting solar power. Solution-processed photovoltaics are cost-effective to manufacture and offer the potential for physical flexibility. Rapid progress in their development has increased their solar-power conversion efficiencies. The nanometre (electron) and micrometre (photon) scale interfaces between the crystalline domains that make up solution-processed solar cells are crucial for efficient charge transport. These interfaces include large surface area junctions between photoelectron donors and acceptors, the intralayer grain boundaries within the absorber, and the interfaces between photoactive layers and the top and bottom contacts. Controlling the collection and minimizing the trapping of charge carriers at these boundaries is crucial to efficiency.

  2. 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.

  3. Non-uniform Solute Segregation at Semi-Coherent Metal/Oxide Interfaces

    Science.gov (United States)

    Choudhury, Samrat; Aguiar, Jeffery A.; Fluss, Michael J.; Hsiung, Luke L.; Misra, Amit; Uberuaga, Blas P.

    2015-08-01

    The properties and performance of metal/oxide nanocomposites are governed by the structure and chemistry of the metal/oxide interfaces. Here we report an integrated theoretical and experimental study examining the role of interfacial structure, particularly misfit dislocations, on solute segregation at a metal/oxide interface. We find that the local oxygen environment, which varies significantly between the misfit dislocations and the coherent terraces, dictates the segregation tendency of solutes to the interface. Depending on the nature of the solute and local oxygen content, segregation to misfit dislocations can change from attraction to repulsion, revealing the complex interplay between chemistry and structure at metal/oxide interfaces. These findings indicate that the solute chemistry at misfit dislocations is controlled by the dislocation density and oxygen content. Fundamental thermodynamic concepts - the Hume-Rothery rules and the Ellingham diagram - qualitatively predict the segregation behavior of solutes to such interfaces, providing design rules for novel interfacial chemistries.

  4. 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.

  5. Materials interface engineering for solution-processed photovoltaics

    KAUST Repository

    Graetzel, Michael

    2012-08-15

    Advances in solar photovoltaics are urgently needed to increase the performance and reduce the cost of harvesting solar power. Solution-processed photovoltaics are cost-effective to manufacture and offer the potential for physical flexibility. Rapid progress in their development has increased their solar-power conversion efficiencies. The nanometre (electron) and micrometre (photon) scale interfaces between the crystalline domains that make up solution-processed solar cells are crucial for efficient charge transport. These interfaces include large surface area junctions between photoelectron donors and acceptors, the intralayer grain boundaries within the absorber, and the interfaces between photoactive layers and the top and bottom contacts. Controlling the collection and minimizing the trapping of charge carriers at these boundaries is crucial to efficiency. © 2012 Macmillan Publishers Limited. All rights reserved.

  6. Materials interface engineering for solution-processed photovoltaics

    KAUST Repository

    Graetzel, Michael; Janssen, René A. J.; Mitzi, David B.; Sargent, Edward H.

    2012-01-01

    Advances in solar photovoltaics are urgently needed to increase the performance and reduce the cost of harvesting solar power. Solution-processed photovoltaics are cost-effective to manufacture and offer the potential for physical flexibility. Rapid progress in their development has increased their solar-power conversion efficiencies. The nanometre (electron) and micrometre (photon) scale interfaces between the crystalline domains that make up solution-processed solar cells are crucial for efficient charge transport. These interfaces include large surface area junctions between photoelectron donors and acceptors, the intralayer grain boundaries within the absorber, and the interfaces between photoactive layers and the top and bottom contacts. Controlling the collection and minimizing the trapping of charge carriers at these boundaries is crucial to efficiency. © 2012 Macmillan Publishers Limited. All rights reserved.

  7. Salt Repository Project transportation system interface requirements: Transportation system/repository receiving facility interface requirements

    International Nuclear Information System (INIS)

    Smith, L.A.; Insalaco, J.W.; Trainer, T.A.

    1988-01-01

    This report is a preliminary review of the interface between the transportation system and the repository receiving facility for a nuclear waste mined geologic disposal system in salt. Criteria for generic cask and facility designs are developed. These criteria are derived by examining the interfaces that occur as a result of the operations needed to receive nuclear waste at a repository. These criteria provide the basis for design of a safe, operable, practical nuclear waste receiving facility. The processing functions required to move the shipping unit from the gate into the unloading area and back to the gate for dispatch are described. Criteria for a generic receiving facility are discussed but no specific facility design is presented or evaluated. The criteria are stated in general terms to allow application to a wide variety of cask and facility designs. 9 refs., 6 figs., 4 tabs

  8. 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

  9. Solution Behavior and Activity of a Halophilic Esterase under High Salt Concentration

    Science.gov (United States)

    Rao, Lang; Zhao, Xiubo; Pan, Fang; Li, Yin; Xue, Yanfen; Ma, Yanhe; Lu, Jian R.

    2009-01-01

    Background Halophiles are extremophiles that thrive in environments with very high concentrations of salt. Although the salt reliance and physiology of these extremophiles have been widely investigated, the molecular working mechanisms of their enzymes under salty conditions have been little explored. Methodology/Principal Findings A halophilic esterolytic enzyme LipC derived from archeaon Haloarcula marismortui was overexpressed from Escherichia coli BL21. The purified enzyme showed a range of hydrolytic activity towards the substrates of p-nitrophenyl esters with different alkyl chains (n = 2−16), with the highest activity being observed for p-nitrophenyl acetate, consistent with the basic character of an esterase. The optimal esterase activities were found to be at pH 9.5 and [NaCl] = 3.4 M or [KCl] = 3.0 M and at around 45°C. Interestingly, the hydrolysis activity showed a clear reversibility against changes in salt concentration. At the ambient temperature of 22°C, enzyme systems working under the optimal salt concentrations were very stable against time. Increase in temperature increased the activity but reduced its stability. Circular dichroism (CD), dynamic light scattering (DLS) and small angle neutron scattering (SANS) were deployed to determine the physical states of LipC in solution. As the salt concentration increased, DLS revealed substantial increase in aggregate sizes, but CD measurements revealed the maximal retention of the α-helical structure at the salt concentration matching the optimal activity. These observations were supported by SANS analysis that revealed the highest proportion of unimers and dimers around the optimal salt concentration, although the coexistent larger aggregates showed a trend of increasing size with salt concentration, consistent with the DLS data. Conclusions/Significance The solution α-helical structure and activity relation also matched the highest proportion of enzyme unimers and dimers. Given that

  10. 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

  11. 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)

  12. 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.

  13. 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.

  14. Isolation of transplutonium elements on ion exchangers from solutions of high salt concentration

    International Nuclear Information System (INIS)

    Guseva, L.I.; Tikhomirova, G.S.; Stepushkina, V.V.

    1985-01-01

    The behaviour of transplutonium elements (TPE) on cation and anion exchangers in aqueous alcoholic solutions of chlorides and nitrates of some alkali and alkaline earth metals depending on different factors: salt concentration, content of alcohol and of acid in the solution as well as the nature of a cation was studied. The data obtained were used to determine the optimal conditions of concentration of TPE on ion exchangers from solutions containing great quantities of salts. The advantages of the use of aqueous alcoholic solutions of nitric acid in the isolation of TPE are shown. (author)

  15. 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.

  16. 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

  17. 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.

  18. 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

  19. 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.

  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.

  1. 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

  2. Physicochemistry of the plasma-electrolyte solution interface

    International Nuclear Information System (INIS)

    Chen Qiang; Saito, Kenji; Takemura, Yu-ichiro; Shirai, Hajime

    2008-01-01

    The atmospheric rf plasma discharge was successfully investigated using NaOH or HCl electrolyte solutions as a counter electrode at different pH values. The emission intensities of solution components, self bias, and electron density strongly depend on the pH value of electrolyte. An addition of ethanol to the electrolyte solutions enhanced the dehydration, which markedly promoted the emissions of solution components as well as electrons from the solution. An acidification of the solution was always observed after the plasma exposure and two coexisting mechanisms were proposed to give a reasonable interpretation. The plasma-electrolyte interface was discussed based on a model of hydrogen cycle

  3. 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

  4. 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.

  5. 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...

  6. 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....

  7. 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.

  8. STABILITY OF A CYLINDRICAL SOLUTE-SOLVENT INTERFACE: EFFECT OF GEOMETRY, ELECTROSTATICS, AND HYDRODYNAMICS.

    Science.gov (United States)

    Li, B O; Sun, Hui; Zhou, Shenggao

    The solute-solvent interface that separates biological molecules from their surrounding aqueous solvent characterizes the conformation and dynamics of such molecules. In this work, we construct a solvent fluid dielectric boundary model for the solvation of charged molecules and apply it to study the stability of a model cylindrical solute-solvent interface. The motion of the solute-solvent interface is defined to be the same as that of solvent fluid at the interface. The solvent fluid is assumed to be incompressible and is described by the Stokes equation. The solute is modeled simply by the ideal-gas law. All the viscous force, hydrostatic pressure, solute-solvent van der Waals interaction, surface tension, and electrostatic force are balanced at the solute-solvent interface. We model the electrostatics by Poisson's equation in which the solute-solvent interface is treated as a dielectric boundary that separates the low-dielectric solute from the high-dielectric solvent. For a cylindrical geometry, we find multiple cylindrically shaped equilibrium interfaces that describe polymodal (e.g., dry and wet) states of hydration of an underlying molecular system. These steady-state solutions exhibit bifurcation behavior with respect to the charge density. For their linearized systems, we use the projection method to solve the fluid equation and find the dispersion relation. Our asymptotic analysis shows that, for large wavenumbers, the decay rate is proportional to wavenumber with the proportionality half of the ratio of surface tension to solvent viscosity, indicating that the solvent viscosity does affect the stability of a solute-solvent interface. Consequences of our analysis in the context of biomolecular interactions are discussed.

  9. 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.

  10. 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.

  11. An induced current method for measuring zeta potential of electrolyte solution-air interface.

    Science.gov (United States)

    Song, Yongxin; Zhao, Kai; Wang, Junsheng; Wu, Xudong; Pan, Xinxiang; Sun, Yeqing; Li, Dongqing

    2014-02-15

    This paper reports a novel and very simple method for measuring the zeta potential of electrolyte solution-air interface. When a measuring electrode contacts the electrolyte solution-air interface, an electrical current will be generated due to the potential difference between the electrode-air surface and the electrolyte solution-air interface. The amplitude of the measured electric signal is linearly proportional to this potential difference; and depends only on the zeta potential at the electrolyte solution-air interface, regardless of the types and concentrations of the electrolyte. A correlation between the zeta potential and the measured voltage signal is obtained based on the experimental data. Using this equation, the zeta potential of any electrolyte solution-air interface can be evaluated quickly and easily by inserting an electrode through the electrolyte solution-air interface and measuring the electrical signal amplitude. This method was verified by comparing the obtained results of NaCl, MgCl2 and CaCl2 solutions of different pH values and concentrations with the zeta potential data reported in the published journal papers. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. 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...

  13. Regularities of ions and surfactants adsorption on metal corrosion products and salt deposites

    International Nuclear Information System (INIS)

    Batrakov, V.V.; Gorichev, I.G.; Martynova, T.V.; Gutenev, A.V.

    1994-01-01

    Adsorption of ions on oxide/solution interface is described using the concepts of existence of acid-base equilibria and assumptions of the Graham-Parson theory on the structure of double electric layer. It is shown that adsorption data are in a good agreement with theoretical aspects. The influence of solution pH on adsorption of certain surfactant organic substances on oxide/solution interface was discussed. Data on adsorption of surfactants on salts-silver iodide and calcium carbonate - are dicussed making allowance for the structure of double electric layer

  14. Smart mobility solution with multiple input Output interface.

    Science.gov (United States)

    Sethi, Aartika; Deb, Sujay; Ranjan, Prabhat; Sardar, Arghya

    2017-07-01

    Smart wheelchairs are commonly used to provide solution for mobility impairment. However their usage is limited primarily due to high cost owing from sensors required for giving input, lack of adaptability for different categories of input and limited functionality. In this paper we propose a smart mobility solution using smartphone with inbuilt sensors (accelerometer, camera and speaker) as an input interface. An Emotiv EPOC+ is also used for motor imagery based input control synced with facial expressions in cases of extreme disability. Apart from traction, additional functions like home security and automation are provided using Internet of Things (IoT) and web interfaces. Although preliminary, our results suggest that this system can be used as an integrated and efficient solution for people suffering from mobility impairment. The results also indicate a decent accuracy is obtained for the overall system.

  15. 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 ...

  16. 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

  17. 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

  18. 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

  19. 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.

  20. 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 ...

  1. 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.

  2. 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

  3. 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)

  4. 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)

  5. 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

  6. Direct Analysis of Proteins from Solutions with High Salt Concentration Using Laser Electrospray Mass Spectrometry

    Science.gov (United States)

    Karki, Santosh; Shi, Fengjian; Archer, Jieutonne J.; Sistani, Habiballah; Levis, Robert J.

    2018-05-01

    The detection of lysozyme, or a mixture of lysozyme, cytochrome c, and myoglobin, from solutions with varying salt concentrations (0.1 to 250 mM NaCl) is compared using laser electrospray mass spectrometry (LEMS) and electrospray ionization-mass spectrometry (ESI-MS). Protonated protein peaks were observed up to a concentration of 250 mM NaCl in the case of LEMS. In the case of ESI-MS, a protein solution with salt concentration > 0.5 mM resulted in predominantly salt-adducted features, with suppression of the protonated protein ions. The constituents in the mixture of proteins were assignable up to 250 mM NaCl for LEMS and were not assignable above a NaCl concentration of 0.5 mM for ESI. The average sodium adducts () bound to the 7+ charge state of lysozyme for LEMS measurements from salt concentrations of 2.5, 25, 50, and 100 mM NaCl are 1.71, 5.23, 5.26, and 5.11, respectively. The conventional electrospray measurements for lysozyme solution containing salt concentrations of 0.1, 1, 2, and 5 mM NaCl resulted in of 2.65, 6.44, 7.57, and 8.48, respectively. LEMS displays an approximately two orders of magnitude higher salt tolerance in comparison with conventional ESI-MS. The non-equilibrium partitioning of proteins on the surface of the charged droplets is proposed as the mechanism for the high salt tolerance phenomena observed in the LEMS measurements. [Figure not available: see fulltext.

  7. 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)

  8. 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...

  9. 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...

  10. 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.

  11. 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)

  12. Dynamic Sensing of Localized Corrosion at the Metal/Solution Interface

    Directory of Open Access Journals (Sweden)

    Shenhao Chen

    2012-04-01

    Full Text Available A Mach-Zehnder interferometer is employed to detect localized corrosion at the metal/solution interface in the potentiodynamic sweep of the iron electrode in solutions. During the electrochemical reactions, local variations of the electrolyte’s refractive index, which correlate with the concentration of dissolved species, change the optical path length (OPL of the object beam when the beam passes through the electrolyte. The distribution of the OPL difference was obtained to present the concentration change of the metal ions visually, which enable direct evidence of corrosion processes. The OPL difference distribution shows localized and general corrosion during the anodic dissolution of the iron electrode in solutions with and without chloride ions, respectively. This method provides an approach for dynamic detection of localized corrosion at the metal/solution interface.

  13. 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.

  14. 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

  15. 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

  16. 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

  17. 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)

  18. ELECTRODIALYSIS IN THE CONVERSION STEP OF THE CONCENTRATED SALT SOLUTIONS IN THE PROCESS OF BATTERY SCRAP

    Directory of Open Access Journals (Sweden)

    S. I. Niftaliev

    2014-01-01

    Full Text Available Summary. The concentrated sodium sulfate solution is formed during the processing of waste battery scrap. A promising way to further treatment of the concentrated salt solution could be the conversion of these salts into acid and bases by electrodialysis, that can be reused in the same technical process cycle. For carrying out the process of conversion of salts into the corresponding acid and base several cells schemes with different combinations of cation, anion and bipolar membranes are used. At this article a comparative analysis of these cells is carried out. In the cells there were used the membranes МC-40, МА-41 and МB-2I. Acid and base solutions with higher concentration may be obtained during the process of electrodialysis in the circulation mode, when a predetermined amount of salt in the closed loop is run through a set of membranes to obtain the desired concentration of the product. The disadvantages of this method are the high cost of buffer tanks and the need to work with small volumes of treated solutions. In industrial applications it is advisable to use continuous electrodialysis with bipolar membranes, since this configuration allows to increase the number of repeating sections, which is necessary to reduce the energy costs. The increase of the removal rate of salts can be achieved by increasing the process steps, and to produce a more concentrated products after the conversion step can be applied electrodialysis-concentrator or evaporator.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

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

    Directory of Open Access Journals (Sweden)

    Jefferson Luiz de Aguiar Paes

    2014-10-01

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

  6. Microspatial ecotone dynamics at a shifting range limit: plant-soil variation across salt marsh-mangrove interfaces.

    Science.gov (United States)

    Yando, E S; Osland, M J; Hester, M W

    2018-05-01

    Ecotone dynamics and shifting range limits can be used to advance our understanding of the ecological implications of future range expansions in response to climate change. In the northern Gulf of Mexico, the salt marsh-mangrove ecotone is an area where range limits and ecotone dynamics can be studied in tandem as recent decreases in winter temperature extremes have allowed for mangrove expansion at the expense of salt marsh. In this study, we assessed aboveground and belowground plant-soil dynamics across the salt marsh-mangrove ecotone quantifying micro-spatial patterns in horizontal extent. Specifically, we studied vegetation and rooting dynamics of large and small trees, the impact of salt marshes (e.g. species and structure) on mangroves, and the influence of vegetation on soil properties along transects from underneath the mangrove canopy into the surrounding salt marsh. Vegetation and rooting dynamics differed in horizontal reach, and there was a positive relationship between mangrove tree height and rooting extent. We found that the horizontal expansion of mangrove roots into salt marsh extended up to eight meters beyond the aboveground boundary. Variation in vegetation structure and local hydrology appear to control mangrove seedling dynamics. Finally, soil carbon density and organic matter did not differ within locations across the salt marsh-mangrove interface. By studying aboveground and belowground variation across the ecotone, we can better predict the ecological effects of continued range expansion in response to climate change.

  7. Microspatial ecotone dynamics at a shifting range limit: plant–soil variation across salt marsh–mangrove interfaces

    Science.gov (United States)

    Yando, Erik S.; Osland, Michael J.; Hester, Mark H.

    2018-01-01

    Ecotone dynamics and shifting range limits can be used to advance our understanding of the ecological implications of future range expansions in response to climate change. In the northern Gulf of Mexico, the salt marsh–mangrove ecotone is an area where range limits and ecotone dynamics can be studied in tandem as recent decreases in winter temperature extremes have allowed for mangrove expansion at the expense of salt marsh. In this study, we assessed aboveground and belowground plant–soil dynamics across the salt marsh–mangrove ecotone quantifying micro-spatial patterns in horizontal extent. Specifically, we studied vegetation and rooting dynamics of large and small trees, the impact of salt marshes (e.g. species and structure) on mangroves, and the influence of vegetation on soil properties along transects from underneath the mangrove canopy into the surrounding salt marsh. Vegetation and rooting dynamics differed in horizontal reach, and there was a positive relationship between mangrove tree height and rooting extent. We found that the horizontal expansion of mangrove roots into salt marsh extended up to eight meters beyond the aboveground boundary. Variation in vegetation structure and local hydrology appear to control mangrove seedling dynamics. Finally, soil carbon density and organic matter did not differ within locations across the salt marsh-mangrove interface. By studying aboveground and belowground variation across the ecotone, we can better predict the ecological effects of continued range expansion in response to climate change.

  8. Relative Order of Sulfuric Acid, Bisulfate, Hydronium, and Cations at the Air-Water Interface.

    Science.gov (United States)

    Hua, Wei; Verreault, Dominique; Allen, Heather C

    2015-11-04

    Sulfuric acid (H2SO4), bisulfate (HSO4(-)), and sulfate (SO4(2-)) are among the most abundant species in tropospheric and stratospheric aerosols due to high levels of atmospheric SO2 emitted from biomass burning and volcanic eruptions. The air/aqueous interfaces of sulfuric acid and bisulfate solutions play key roles in heterogeneous reactions, acid rain, radiative balance, and polar stratospheric cloud nucleation. Molecular-level knowledge about the interfacial distribution of these inorganic species and their perturbation of water organization facilitates a better understanding of the reactivity and growth of atmospheric aerosols and of the aerosol surface charge, thus shedding light on topics of air pollution, climate change, and thundercloud electrification. Here, the air/aqueous interface of NaHSO4, NH4HSO4, and Mg(HSO4)2 salt solutions as well as H2SO4 and HCl acid solutions are investigated by means of vibrational sum frequency generation (VSFG) and heterodyne-detected (HD) VSFG spectroscopy. VSFG spectra of all acid solutions show higher SFG response in the OH-bonded region relative to neat water, with 1.1 M H2SO4 being more enhanced than 1.1 M HCl. In addition, VSFG spectra of bisulfate salt solutions highly resemble that of the dilute H2SO4 solution (0.26 M) at a comparable pH. HD-VSFG (Im χ((2))) spectra of acid and bisulfate salt solutions further reveal that hydrogen-bonded water molecules are oriented preferentially toward the bulk liquid phase. General agreement between Im χ((2)) spectra of 1.1 M H2SO4 and 1.1 M HCl acid solutions indicate that HSO4(-) ions have a similar surface preference as that of chloride (Cl(-)) ions. By comparing the direction and magnitude of the electric fields arising from the interfacial ion distributions and the concentration of each species, the most reasonable relative surface preference that can be deduced from a simplified model follows the order H3O(+) > HSO4(-) > Na(+), NH4(+), Mg(2+) > SO4(2-). Interestingly

  9. 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.

  10. Sodium concentration in home made salt – sugar – solution (sss ...

    African Journals Online (AJOL)

    In a cohort of 210 young mothers, selected through cluster sampling technique from Ogida health district of Egor Local Government Area of Edo State, the electrolyte concentration of prepared salt-sugar-solutions (SSS) were evaluated. This was predicated on the need to determine the effects of introduction of various ...

  11. Aggregation of Heteropolyanions Implicates the Presence of Zundel Ions Near Air-Water Interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Bera, Mrinal K. [Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne Illinois 60439 United States; DUBBLE-CRG, ESRF-The European Synchrotron Radiation Facility CS40220, 38043 Grenoble Cedex 9 France; Antonio, Mark R. [Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne Illinois 60439 United States

    2016-07-01

    Protons play crucial roles in the interactions between hetero-polyanions (HPAs) in aqueous solutions and solid acid salts. We report the aggregation behaviours of Keggin HPAs near the surfaces of heteropolyacid solutions. The structure of the aggregated HPA layer near the solution-vapour phase boundary closely resembles the solid-state crystal structure of the hetero-polyacids in which the HPAs are connected by Zundel ions. The resemblance not only implicates the presence of protons in the form of planar Zundel ions near the air-water interface but, also, suggests that these align parallel to the interface. This study demonstrates an indirect means of assessing the impact of protons on HPA interactions near air-water interfaces and, in general, provides new insights about interfacial proton chemistry of heteropolyacids.

  12. 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

  13. Spectral Solutions of Self-adjoint Elliptic Problems with Immersed Interfaces

    International Nuclear Information System (INIS)

    Auchmuty, G.; Klouček, P.

    2011-01-01

    This paper describes a spectral representation of solutions of self-adjoint elliptic problems with immersed interfaces. The interface is assumed to be a simple non-self-intersecting closed curve that obeys some weak regularity conditions. The problem is decomposed into two problems, one with zero interface data and the other with zero exterior boundary data. The problem with zero interface data is solved by standard spectral methods. The problem with non-zero interface data is solved by introducing an interface space H Γ (Ω) and constructing an orthonormal basis of this space. This basis is constructed using a special class of orthogonal eigenfunctions analogously to the methods used for standard trace spaces by Auchmuty (SIAM J. Math. Anal. 38, 894–915, 2006). Analytical and numerical approximations of these eigenfunctions are described and some simulations are presented.

  14. Kinetics of Surfactant Desorption at an Air–Solution Interface

    KAUST Repository

    Morgan, C. E.; Breward, C. J. W.; Griffiths, I. M.; Howell, P. D.; Penfold, J.; Thomas, R. K.; Tucker, I.; Petkov, J. T.; Webster, J. R. P.

    2012-01-01

    The kinetics of re-equilibration of the anionic surfactant sodium dodecylbenzene sulfonate at the air-solution interface have been studied using neutron reflectivity. The experimental arrangement incorporates a novel flow cell in which the subphase

  15. 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

  16. 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....

  17. Whispering Gallery Mode Based Optical Fiber Sensor for Measuring Concentration of Salt Solution

    Directory of Open Access Journals (Sweden)

    Chia-Chin Chiang

    2013-01-01

    Full Text Available An optical fiber solution-concentration sensor based on whispering gallery mode (WGM is proposed in this paper. The WGM solution-concentration sensors were used to measure salt solutions, in which the concentrations ranged from 1% to 25% and the wavelength drifted from the left to the right. The experimental results showed an average sensitivity of approximately 0.372 nm/% and an R2 linearity of 0.8835. The proposed WGM sensors are of low cost, feasible for mass production, and durable for solution-concentration sensing.

  18. 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.

  19. 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.

  20. 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...

  1. 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

  2. Analytical solution of laminar-laminar stratified two-phase flows with curved interfaces

    International Nuclear Information System (INIS)

    Brauner, N.; Rovinsky, J.; Maron, D.M.

    1995-01-01

    The present study represents a complete analytical solution for laminar two-phase flows with curved interfaces. The solution of the Navier-Stokes equations for the two-phases in bipolar coordinates provides the 'flow monograms' describe the relation between the interface curvature and the insitu flow geometry when given the phases flow rates and viscosity ratios. Energy considerations are employed to construct the 'interface monograms', whereby the characteristic interfacial curvature is determined in terms of the phases insitu holdup, pipe diameter, surface tension, fluids/wall adhesion and gravitation. The two monograms are then combined to construct the system 'operational monogram'. The 'operational monogram' enables the determination of the interface configuration, the local flow characteristics, such as velocity profiles, wall and interfacial shear stresses distribution as well as the integral characteristics of the two-phase flow: phases insitu holdup and pressure drop

  3. Analytical solution of laminar-laminar stratified two-phase flows with curved interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Brauner, N.; Rovinsky, J.; Maron, D.M. [Tel-Aviv Univ. (Israel)

    1995-09-01

    The present study represents a complete analytical solution for laminar two-phase flows with curved interfaces. The solution of the Navier-Stokes equations for the two-phases in bipolar coordinates provides the `flow monograms` describe the relation between the interface curvature and the insitu flow geometry when given the phases flow rates and viscosity ratios. Energy considerations are employed to construct the `interface monograms`, whereby the characteristic interfacial curvature is determined in terms of the phases insitu holdup, pipe diameter, surface tension, fluids/wall adhesion and gravitation. The two monograms are then combined to construct the system `operational monogram`. The `operational monogram` enables the determination of the interface configuration, the local flow characteristics, such as velocity profiles, wall and interfacial shear stresses distribution as well as the integral characteristics of the two-phase flow: phases insitu holdup and pressure drop.

  4. 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.

  5. 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

  6. 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...

  7. Systematic Evaluation of Salt Cavern Well Integrity

    Science.gov (United States)

    Roberts, B. L.; Lord, D. L.; Lord, A. S.; Bettin, G.; Sobolik, S. R.; Park, B. Y.

    2017-12-01

    The U.S. Strategic Petroleum Reserve (SPR) holds a reserve of crude oil ( 700 million barrels) to help ease any interruptions in oil import to the United States. The oil is stored in a set of 63 underground caverns distributed across four sites along the U.S. Gulf Coast. The caverns were solution mined into salt domes at each of the four sites. The plastic nature of the salt is beneficial for the storage of crude oil as it heals any fractures that may occur in the salt. The SPR is responsible for operating and maintaining the nearly 120 wells used to access the storage caverns over operational lifetimes spanning decades. Salt creep can induce deformation of the well casing which must be remediated to insure cavern and well integrity. This is particularly true at the interface between the plastic salt and the rigid caprock. The Department of Energy, the SPR Management and Operations contractor, and Sandia National Laboratories has developed a multidimensional well-grading system for the salt cavern access wells. This system is designed to assign numeric grades to each well indicating its risk of losing integrity and remediation priority. The system consists of several main components which themselves may consist of sub-components. The main components consider such things as salt cavern pressure history, results from geomechanical simulations modeling salt deformation, and measurements of well casing deformation due to salt creep. In addition, the geology of the salt domes and their overlying caprock is also included in the grading. These multiple factors are combined into summary values giving the monitoring and remediation priority for each well. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc. for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-NA0003525.

  8. 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.

  9. 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

  10. 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

  11. 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

  12. 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.

  13. 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

  14. Human-computer interfaces applied to numerical solution of the Plateau problem

    Science.gov (United States)

    Elias Fabris, Antonio; Soares Bandeira, Ivana; Ramos Batista, Valério

    2015-09-01

    In this work we present a code in Matlab to solve the Problem of Plateau numerically, and the code will include human-computer interface. The Problem of Plateau has applications in areas of knowledge like, for instance, Computer Graphics. The solution method will be the same one of the Surface Evolver, but the difference will be a complete graphical interface with the user. This will enable us to implement other kinds of interface like ocular mouse, voice, touch, etc. To date, Evolver does not include any graphical interface, which restricts its use by the scientific community. Specially, its use is practically impossible for most of the Physically Challenged People.

  15. 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.

  16. 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

  17. 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

  18. 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)

  19. 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

  20. 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

  1. 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

  2. Turbulent solutal convection and surface patterning in solid dissolution

    International Nuclear Information System (INIS)

    Sullivan, T.S.; Liu, Y.; Ecke, R.E.

    1996-01-01

    We describe experiments in which crystals of NaCl, KBr, and KCl are dissolved from below by aqueous solutions containing concentrations of the respective salts from zero concentration to near saturation. The solution near the solid-liquid interface is gravitationally unstable, producing turbulent hydrodynamic motion similar to thermal convection from a single surface cooled from above. The coupling of the fluid flow with the solid dissolution produces irregular patterns at the solid-liquid interface with a distribution of horizontal length scales. The dissolution mass flux and the pattern length scales are compared with a turbulent boundary layer model. Remarkable agreement is found, showing that the fluid motion controls both the dissolution rate and the interface patterning. copyright 1996 The American Physical Society

  3. A new variable temperature solution-solid interface scanning tunneling microscope.

    Science.gov (United States)

    Jahanbekam, Abdolreza; Mazur, Ursula; Hipps, K W

    2014-10-01

    We present a new solution-solid (SS) interface scanning tunneling microscope design that enables imaging at high temperatures with low thermal drift and with volatile solvents. In this new design, distinct from the conventional designs, the entire microscope is surrounded in a controlled-temperature and controlled-atmosphere chamber. This allows users to take measurements at high temperatures while minimizing thermal drift. By incorporating an open solution reservoir in the chamber, solvent evaporation from the sample is minimized; allowing users to use volatile solvents for temperature dependent studies at high temperatures. The new design enables the user to image at the SS interface with some volatile solvents for long periods of time (>24 h). An increase in the nonlinearity of the piezoelectric scanner in the lateral direction as a function of temperature is addressed. A temperature dependent study of cobalt(II) octaethylporphyrin (CoOEP) at the toluene/Au(111) interface has been performed with this instrument. It is demonstrated that the lattice parameters remain constant within experimental error from 24 °C to 75 °C. Similar quality images were obtained over the entire temperature range. We report the unit cell of CoOEP at the toluene/Au(111) interface (based on two molecules per unit cell) to be A = (1.36 ± 0.04) nm, B = (2.51 ± 0.04) nm, and α = 97° ± 2°.

  4. 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)

  5. Effects of nanoparticle heating on the structure of a concentrated aqueous salt solution.

    Science.gov (United States)

    Sindt, Julien O; Alexander, Andrew J; Camp, Philip J

    2017-12-07

    The effects of a rapidly heated nanoparticle on the structure of a concentrated aqueous salt solution are studied using molecular dynamics simulations. A diamond-like nanoparticle of radius 20 Å is immersed in a sodium-chloride solution at 20% above the experimental saturation concentration and equilibrated at T = 293 K and P = 1 atm. The nanoparticle is then rapidly heated to several thousand degrees Kelvin, and the system is held under isobaric-isoenthalpic conditions. It is observed that after 2-3 ns, the salt ions are depleted far more than water molecules from a proximal zone 15-25 Å from the nanoparticle surface. This leads to a transient reduction in molality in the proximal zone and an increase in ion clustering in the distal zone. At longer times, ions begin to diffuse back into the proximal zone. It is speculated that the formation of proximal and distal zones, and the increase in ion clustering, plays a role in the mechanism of nonphotochemical laser-induced nucleation.

  6. Effects of nanoparticle heating on the structure of a concentrated aqueous salt solution

    Science.gov (United States)

    Sindt, Julien O.; Alexander, Andrew J.; Camp, Philip J.

    2017-12-01

    The effects of a rapidly heated nanoparticle on the structure of a concentrated aqueous salt solution are studied using molecular dynamics simulations. A diamond-like nanoparticle of radius 20 Å is immersed in a sodium-chloride solution at 20% above the experimental saturation concentration and equilibrated at T = 293 K and P = 1 atm. The nanoparticle is then rapidly heated to several thousand degrees Kelvin, and the system is held under isobaric-isoenthalpic conditions. It is observed that after 2-3 ns, the salt ions are depleted far more than water molecules from a proximal zone 15-25 Å from the nanoparticle surface. This leads to a transient reduction in molality in the proximal zone and an increase in ion clustering in the distal zone. At longer times, ions begin to diffuse back into the proximal zone. It is speculated that the formation of proximal and distal zones, and the increase in ion clustering, plays a role in the mechanism of nonphotochemical laser-induced nucleation.

  7. Interactions of U(VI), Nd, and Th(IV) at the Calcite-solution interface

    International Nuclear Information System (INIS)

    Carroll, S.A.; Dran, J.C.

    1992-01-01

    The interactions of U(VI), Nd, and Th(IV) at the calcite-solution interface at controlled pCO 2 (g) have been investigated by Rutherford backscattering (RBS), scanning electron microscopy (SEM) and energy dispersive (EDS) analyses of reacted calcite. Uranium precipitation at the calcite-solution interface was observed only for those experiments in which the initial [U(VI)] was greater than the solubility of rutherfordine, UO 2 CO 3 (s). At pH 8.0, flat radial uranium and calcium zoned precipitates form at the mineral-solution interface. At pH 4.3, uranium forms an anastomosing precipitate throughout the calcite surface. RBS analyses confirmed the SEM analyses showing that uranium forms a solid phase within the calcite surface, but formation of an uranium-calcium solid solution at depth is limited. In sharp contrast to U(VI), Nd is concentrated in the solid phase as individual neodymium-calcium carbonate crystals. Calcite and pure orthorhombic neodymium carbonate crystals dissolve at the expense of the formation of a more stable neodymium-calcium solid solution. In the presence of calcite, a thorium-calcium solid solution forms by exchanging Th for Ca in the calcite structure. Thorium precipitates in two linear trends which intersect each other at approximately 105deg C and 75deg C, parallel to calcite rhombohedral cleavage faces. (orig.)

  8. 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...

  9. Modeling the liquid-liquid interface and the transfer of a solute by molecular dynamics simulation

    International Nuclear Information System (INIS)

    Hayoun, Marc

    1990-11-01

    Molecular Dynamics method and Lennard-Jones potential functions have been employed to model Liquid-Liquid Interfaces. The variation of the miscibilities between the two liquids is obtained by changing the interaction between the two atomic species. The resulting interfaces have a thickness of about three atomic diameters and are stable on the time scale of the simulation. They have been characterized by the density and pressure profiles. The interfacial tension has also been computed and is of the order of magnitude of experimental values. The diffusion process is anisotropic in the interfacial region: the transverse diffusion coefficient (parallelly to the interface) is higher than the normal one. A qualitative explanation of this behaviour is suggested by considering the pressure tensor. The second part of this work, performed by Molecular Dynamics in the canonical ensemble, is devoted to the kinetic study of the transfer of a solute through the interface. A model of a symmetric interface with an atomic solute has been used. The interaction potential between the solute and the solvents has been built in order to obtain an activation barrier to the transfer. We have computed the mean force exerted by the solvent on the solute as a function of its distance to the interface. The resulting mean force potential corresponds to a free energy difference. The height of the energy barrier involved is about 4 kT. The potential energy and entropy profiles have also been calculated and discussed. The diffusion coefficient of the solute has been computed by equilibrium and non-equilibrium methods. We deduced the friction coefficient of the solvent, which is essential to determine the Kramers transmission coefficient. This coefficient is compared to the one obtained by simulation. Finally, the solute transfer rate constant has been calculated. (author) [fr

  10. 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...

  11. 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

  12. 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

  13. Ion spatial distributions at the liquid-vapor interface of aqueous potassium fluoride solutions

    Energy Technology Data Exchange (ETDEWEB)

    Brown, M A; D' Auria, R; Kuo, I W; Krisch, M J; Starr, D E; Bluhm, H; Tobias, D J; Hemminger, J C

    2008-04-23

    X-ray photoemission spectroscopy operating under ambient pressure conditions is used to probe ion distributions throughout the interfacial region of a free-flowing aqueous liquid micro-jet of 6 M potassium fluoride. Varying the energy of the ejected photoelectrons by carrying out experiments as a function of x-ray wavelength measures the composition of the aqueous-vapor interfacial region at various depths. The F{sup -} to K{sup +} atomic ratio is equal to unity throughout the interfacial region to a depth of 2 nm. The experimental ion profiles are compared with the results of a classical molecular dynamics simulation of a 6 M aqueous KF solution employing polarizable potentials. The experimental results are in qualitative agreement with the simulations when integrated over an exponentially decaying probe depth characteristic of an APPES experiment. First principles molecular dynamics simulations have been used to calculate the potential of mean force for moving a fluoride anion across the air-water interface. The results show that the fluoride anion is repelled from the interface, and this is consistent with the depletion of F{sup -} at the interface revealed by the APPES experiment and polarizable force field-based molecular dynamics simulation. Together, the APPES and MD simulation data provide a detailed description of the aqueous-vapor interface of alkali fluoride systems. This work offers the first direct observation of the ion distribution at a potassium fluoride aqueous solution interface. The current experimental results are compared to those previously obtained for saturated solutions of KBr and KI to underscore the strong difference in surface propensity between soft/large and hard/small halide ions in aqueous solution.

  14. Influence of pH, temperature, and concentration on stabilization of aqueous hornet silk solution and fabrication of salt-free materials.

    Science.gov (United States)

    Kameda, Tsunenori

    2015-01-01

    We found that an aqueous solution of silk from cocoons produced by hornet larvae (hornet silk) can be obtained when the solution is adjusted to basic conditions of pH > 9.2. It is known that native hornet cocoons can be dissolved in concentrated aqueous solution of salts, such as lithium bromide (LiBr) and calcium chloride (CaCl2). Upon the removal of these salts from solution by dialysis, solidification, gelation, or sedimentation of hornet silk is known to occur. In the present study, under basic conditions, however, no such solidification occurred, even after salt removal. In this study, ammonia was used for alkalization of solution because it is volatilized during the casting process and pure hornet silk materials can be obtained after drying. The effects of the concentrations of hornet silk and ammonia, as well as dialysis temperature, on preventing gelation during dialysis were investigated. Dialysis conditions that limit the degradation of hornet silk by hydrolysis in alkali solution were identified. Moreover, casting conditions to prepare flexible and transparent hornet silk film from aqueous ammonia solution were optimized. Molecular structural analysis of hornet silk in aqueous ammonia solution and cast film indicated the formation of α-helix conformations. © 2014 Wiley Periodicals, Inc.

  15. 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.)

  16. 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.

  17. Kinetics of the Reaction of CO2 with Aqueous Potassium Salt of Taurine and Glycine

    NARCIS (Netherlands)

    Kumar, P.S.; Hogendoorn, J.A.; Versteeg, G.F.; Feron, P.H.M.

    2003-01-01

    The kinetics of the reaction between CO2 and aqueous potassium salts of taurine and glycine was measured at 295 K in a stirred-cell reactor with a flat gas–liquid interface. For aqueous potassium taurate solutions, the temperature effect on the reaction kinetics was measured at 285 and 305 K. Unlike

  18. Kinetics of the reaction of CO2 with aqueous potassium salt of taurine and glycine

    NARCIS (Netherlands)

    Kumar Paramasivam Senthil, P.S.; Hogendoorn, Kees; Versteeg, Geert; Feron, P.H.M.

    2003-01-01

    The kinetics of the reaction between CO2 and aqueous potassium salts of taurine and glycine was measured at 295 K in a stirred-cell reactor with a flat gas-liquid interface. For aqueous potassium taurate solutions, the temperature effect on the reaction kinetics was measured at 285 and 305 K. Unlike

  19. Hofmeister Effect on PNIPAM in Bulk and at an Interface: Surface Partitioning of Weakly Hydrated Anions

    DEFF Research Database (Denmark)

    Moghaddam, Saeed Zajforoushan; Thormann, Esben

    2017-01-01

    The effect of sodium fluoride, sodium trichloroacetate, and sodium thiocyanate on the stability and conformation of poly(N-isopropylacrylamide), in bulk solution and at the gold-aqueous interface, is investigated by differential scanning calorimetry, dynamic light scattering, quartz crystal...... for thiocyanate and trichloroacetate, a salting-out effect is found for sodium trichloroacetate. This apparent contradiction is explained by a combination of previously suggested mechanisms for the salting-out effect by weakly hydrated anions....

  20. 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)

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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

  6. 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

  7. 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.

  8. 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.

  9. 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...

  10. Modeling Europa's Ice-Ocean Interface

    Science.gov (United States)

    Elsenousy, A.; Vance, S.; Bills, B. G.

    2014-12-01

    This work focuses on modeling the ice-ocean interface on Jupiter's Moon (Europa); mainly from the standpoint of heat and salt transfer relationship with emphasis on the basal ice growth rate and its implications to Europa's tidal response. Modeling the heat and salt flux at Europa's ice/ocean interface is necessary to understand the dynamics of Europa's ocean and its interaction with the upper ice shell as well as the history of active turbulence at this area. To achieve this goal, we used McPhee et al., 2008 parameterizations on Earth's ice/ocean interface that was developed to meet Europa's ocean dynamics. We varied one parameter at a time to test its influence on both; "h" the basal ice growth rate and on "R" the double diffusion tendency strength. The double diffusion tendency "R" was calculated as the ratio between the interface heat exchange coefficient αh to the interface salt exchange coefficient αs. Our preliminary results showed a strong double diffusion tendency R ~200 at Europa's ice-ocean interface for plausible changes in the heat flux due to onset or elimination of a hydrothermal activity, suggesting supercooling and a strong tendency for forming frazil ice.

  11. 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.

  12. 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.)

  13. Voltammetry for the charge transfer at two immiscible electrolyte solutions interface

    International Nuclear Information System (INIS)

    Kihara, S.; Suzuki, M.; Maeda, K.; Ogura, K.; Matsui, M.; Yoshida, Z.

    1989-01-01

    The voltammetry for the charge transfer (VCT) at the interface of immicible solutions is a very powerful method for understanding the dynamic features of the charge transfer because of its unmatched advantage that the transfer energy and the number of charges transferred can be measured simultaneously and in situ. In the present paper, several novel systems for electron transfer are outlined, and the following topics are discussed based on results obtained by the current scan polarography at the solution dropping electrode developed as a technique for VCT: the relation between the half-wave potential in VCT for ion transfer and the characteristics of the ion transferred; the relation between the half-wave potential in VCT for electron transfer and the electrochemical nature of a redox couple added in water and that added in organic solution; and the ion transfer through a liquid membrane promoted by electron transfer. Observations are presented and discussion is made on the characteristics of ion transfer polarograms, those of electron transfer polarograms, and ion transfer promoted by electron transfer at a liquid/membrane interface. (N.K.)

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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.

  19. Salt effects in surfactant-free microemulsions

    Science.gov (United States)

    Schöttl, Sebastian; Horinek, Dominik

    2018-06-01

    The weakly associated micellar aggregates found in the so-called "pre-ouzo region" of the surfactant-free microemulsion water/ethanol/1-octanol are sensitive to changes in the system composition and also to the presence of additives like salt. In this work, we study the influence of two salts, sodium iodide and lithium chloride, on aggregates in water/ethanol/1-octanol by molecular dynamics simulations. In both cases, ethanol concentration in the nonpolar phase and at the interface is increased due to a salting out effect on ethanol in the aqueous pseudo-phase. In addition, minor charging of the interface as a consequence of differential adsorption of anions and cations occurs. However, this charge separation is overall weakened by the erratic surface of octanol aggregates, where polar hydroxyl groups and hydrophobic patches are both present. Furthermore, ethanol at the interface shields hydrophobic patches and reduces the preferential adsorption of iodide and lithium.

  20. Observation of carbon growth and interface structures in methanol solution

    Science.gov (United States)

    Okuno, Kimio

    2015-11-01

    In the deposition of carbon on the surface of a tungsten tip in methanol solution by electrolysis, the growth structure of the carbon films, the interface state, and the dissolution of carbon atoms into the tungsten matrix of the substrate have been investigated with the atomic events by field ion microscopy (FIM). The carbon films preferentially condense on the W{111} plane. The interfacial reaction at the carbon atom-tungsten substrate interface is vigorous and the carbon atoms also readily dissolve into the substrate matrix to form a tungsten-carbon complex. The reaction depth of the deposited carbon depends on the magnitude of electrolytic current and the treatment duration in the methanol solution. In this work, the resolution depth of carbon was found to be approximately 270 atomic layers below the top layer of the tungsten substrate by a field evaporation technique. In the case of a low electrolytic current, the tungsten substrate surface is entirely covered with carbon atoms having a pseudomorphic structure. The field-electron emission characteristics were also evaluated for various coverages of the carbon film formed on the substrate.

  1. 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…

  2. 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.

  3. A study of the electrode/solution interface during electrochemical reactions by digital holography

    Directory of Open Access Journals (Sweden)

    SHENHAO CHEN

    2006-10-01

    Full Text Available Digital holography was used to study in situ the dynamic changes of the electrode/solution interface and the solution near the electrode during the anodic process of iron in a sulfuric acid solution. The effects of chloride, bromide and iodine ions on this process were also investigated. The magnetic field also has effects on the process. The effects are discussed in combination with SEM results.

  4. 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.

  5. X-ray scattering on liquid-gas interfaces; Roentgenstreuung an Fluessigkeits-Gas Grenzflaechen

    Energy Technology Data Exchange (ETDEWEB)

    Paulus, Michael

    2006-07-01

    In the framework of this thesis two different theme-fields were studied with dhe methods of the elastic, surface sensitive X-ray scattering. In the first part of the thesis the liquid-gas interfaces water-propane and glycerol-isobutane were studied concerning the structure formation on these interfaces. The system water-propane served for the study of the gas hydrate formation on the water-gas interface. Studies on this interface could give no hints on the formation of propane hydrates or propane-hydrate fragments. However the adsorption of molecularly thin propane films on the water surface was observed. The adsorption behaviour of gases on liquid surfaces was studied by further experiments on the glycerol-isobutane interface. In the second part of the thesis the surfaces of aqueous salt solutions and water were studied. The lateralstructure of these liquid-gas interfaces was studied by the method of the diffuse X-ray scattering.

  6. 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

  7. 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)

  8. Order of wetting transitions in electrolyte solutions.

    Science.gov (United States)

    Ibagon, Ingrid; Bier, Markus; Dietrich, S

    2014-05-07

    For wetting films in dilute electrolyte solutions close to charged walls we present analytic expressions for their effective interface potentials. The analysis of these expressions renders the conditions under which corresponding wetting transitions can be first- or second-order. Within mean field theory we consider two models, one with short- and one with long-ranged solvent-solvent and solvent-wall interactions. The analytic results reveal in a transparent way that wetting transitions in electrolyte solutions, which occur far away from their critical point (i.e., the bulk correlation length is less than half of the Debye length) are always first-order if the solvent-solvent and solvent-wall interactions are short-ranged. In contrast, wetting transitions close to the bulk critical point of the solvent (i.e., the bulk correlation length is larger than the Debye length) exhibit the same wetting behavior as the pure, i.e., salt-free, solvent. If the salt-free solvent is governed by long-ranged solvent-solvent as well as long-ranged solvent-wall interactions and exhibits critical wetting, adding salt can cause the occurrence of an ion-induced first-order thin-thick transition which precedes the subsequent continuous wetting as for the salt-free solvent.

  9. Bovine insulin-phosphatidylcholine mixed Langmuir monolayers: behavior at the air-water interface.

    Science.gov (United States)

    Pérez-López, S; Blanco-Vila, N M; Vila-Romeu, N

    2011-08-04

    The behavior of the binary mixed Langmuir monolayers of bovine insulin (INS) and phosphatidylcholine (PC) spread at the air-water interface was investigated under various subphase conditions. Pure and mixed monolayers were spread on water, on NaOH and phosphate-buffered solutions of pH 7.4, and on Zn(2+)-containing solutions. Miscibility and interactions between the components were studied on the basis of the analysis of the surface pressure (π)-mean molecular area (A) isotherms, surface compression modulus (C(s)(-1))-π curves, and plots of A versus mole fraction of INS (X(INS)). Our results indicate that intermolecular interactions between INS and PC depend on both the monolayer state and the structural characteristics of INS at the interface, which are strongly influenced by the subphase pH and salt content. Brewster angle microscopy (BAM) was applied to investigate the peptide aggregation pattern at the air-water interface in the presence of the studied lipid under any experimental condition investigated. The influence of the lipid on the INS behavior at the interface strongly depends on the subphase conditions.

  10. 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

  11. Interfacial behavior of perchlorate versus chloride ions in saturated aqueous salt solutions

    Energy Technology Data Exchange (ETDEWEB)

    Ghosal, S; Kuo, I W; Baer, M D; Bluhm, H

    2009-04-14

    In recent years combination of theoretical and experimental work have presented a novel view of the aqueous interface wherein hard and/or multiply charged ions are excluded from the interface, but large polarizable anions show interfacial enhancement relative to the bulk. The observed trend in the propensity of anions to adsorb at the air/water interface appears to be reverse of the Hofmeister series for anions. This study focuses on experimental and theoretical examination of the partitioning behavior of perchlorate (ClO{sub 4}{sup -}) and chloride (Cl{sup -}) ions at the air/water interface. We have used ambient pressure X-ray photoelectron spectroscopy technique to directly probe the interfacial concentrations of ClO{sub 4}{sup -} and Cl{sup -} ions in sodium perchlorate and sodium chloride solutions, respectively. Experimental observations are compared with first principles molecular dynamics simulations. Both experimental and simulation results show enhancement of ClO{sub 4}{sup -} ion at the interface, compared with the absence of such enhancement in the case of Cl{sup -} ion. These observations are in agreement with the expected trend in the interfacial propensity of anions based on the Hofmeister series.

  12. 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

  13. 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

  14. 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

  15. 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)

  16. 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.

  17. Electrosynthesis of Copper-Tetracyanoquinodimethane Based on the Coupling Charge Transfer across Water/1,2-Dichloroethane Interface

    International Nuclear Information System (INIS)

    Huang, Li; Li, Pei; Pamphile, Ndagijimana; Tian, Zhong-Qun; Zhan, Dongping

    2014-01-01

    Graphical abstract: - Highlights: • Organic semiconductor CuTCNQ is synthesized through electrochemistry of liquid/liquid interface. • A coupling charge transfer (CCT) mechanism is proposed for organic electrosynthesis. • The obtained CuTCNQ has good electrochemical and electronic properties. - Abstract: The organic salt Copper-Tetracyanoquinodimethane (CuTCNQ) is an important semiconductor used in electronics for field-effect transistors, switches and memory devices. Here we present a novel electrosynthetic method of CuTCNQ microneedles based on the coupling charge transfer across water/1,2-dichloroethane (W/1,2-DCE) interface. A HOPG electrode is covered by a small volume of 1,2-DCE solution, which is further covered by an aqueous solution to construct the W/1,2-DCE interface. When TCNQ in 1,2-DCE phase is reduced on HOPG, Cu 2+ in the aqueous solution will transfer across the W/1,2-DCE interface in order to maintain the electric neutrality. Therein CuTCNQ microneedles are formed which have good solid-state electrochemical and electronic properties. This coupling charge transfer mechanism is valuable and broadens the applications of liquid/liquid interface in organic electrosynthesis

  18. 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.

  19. 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

  20. 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.

  1. 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.

  2. Formation and stabilization of anionic metal complexes in concentrated aqueous quaternary ammonium salt solutions

    International Nuclear Information System (INIS)

    Aronson, F.L.; Hwang, L.L.Y.; Ronca, N.; Solomon, N.A.; Steigman, J.

    1985-01-01

    Anionic complexes of transition metals were stabilized in aqueous solutions containing high concentrations of various short-chain quaternary ammonium salts. Compounds with longer paraffin chains were effective in much less concentrated solution. Complex ions were detected spectrophotometrically. FeCl 4 - , which is usually formed in concentrated HCl, was the predominant Fe(III) complex in 30 m choline chloride containing only 0.12 M HCl. A yellow transitory Tc(VII) chloro-addition intermediate, formed in the reduction of TcO 4 - by concentrated HCl, was stabilized when the solution also contained 25 m choline chloride. Its spectrum, as well as the isolation of an already known Tc(VII) bipyridyl complex, is reported. Concentrated organic electrolytes also stabilized Tc(V) oxide halides against disproportionation and Tc(IV) hexahalides against hydrolysis. Halochromates of Cr(VI) were formed and stabilized in dilute acid containing quaternary ammonium salts. Their UV spectra showed the well-resolved vibronic fine structure associated with the symmetric chromium-to-oxygen charge-transfer band. It is known that these progressions are resolved in aprotic solvents, but not in aqueous acidic solution alone, and that the loss of fine structure in aqueous media is due to hydrogen bonding. The stabilization of anionic metal complexes and the resolution of vibronic structure in halochromates are probably consequences of water-structure-enforced ion paring. The present work suggests that the water molecules in immediate contact with the complex anions are more strongly hydrogen bonded to each other than to the complex. 21 references, 4 figures

  3. 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.

  4. Draft Genome of Scalindua rubra, Obtained from the Interface Above the Discovery Deep Brine in the Red Sea, Sheds Light on Potential Salt Adaptation Strategies in Anammox Bacteria.

    Science.gov (United States)

    Speth, Daan R; Lagkouvardos, Ilias; Wang, Yong; Qian, Pei-Yuan; Dutilh, Bas E; Jetten, Mike S M

    2017-07-01

    Several recent studies have indicated that members of the phylum Planctomycetes are abundantly present at the brine-seawater interface (BSI) above multiple brine pools in the Red Sea. Planctomycetes include bacteria capable of anaerobic ammonium oxidation (anammox). Here, we investigated the possibility of anammox at BSI sites using metagenomic shotgun sequencing of DNA obtained from the BSI above the Discovery Deep brine pool. Analysis of sequencing reads matching the 16S rRNA and hzsA genes confirmed presence of anammox bacteria of the genus Scalindua. Phylogenetic analysis of the 16S rRNA gene indicated that this Scalindua sp. belongs to a distinct group, separate from the anammox bacteria in the seawater column, that contains mostly sequences retrieved from high-salt environments. Using coverage- and composition-based binning, we extracted and assembled the draft genome of the dominant anammox bacterium. Comparative genomic analysis indicated that this Scalindua species uses compatible solutes for osmoadaptation, in contrast to other marine anammox bacteria that likely use a salt-in strategy. We propose the name Candidatus Scalindua rubra for this novel species, alluding to its discovery in the Red Sea.

  5. 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.

  6. Molten Salt Test Loop (MSTL) system customer interface document.

    Energy Technology Data Exchange (ETDEWEB)

    Gill, David Dennis; Kolb, William J.; Briggs, Ronald D.

    2013-09-01

    The National Solar Thermal Test Facility at Sandia National Laboratories has a unique test capability called the Molten Salt Test Loop (MSTL) system. MSTL is a test capability that allows customers and researchers to test components in flowing, molten nitrate salt. The components tested can range from materials samples, to individual components such as flex hoses, ball joints, and valves, up to full solar collecting systems such as central receiver panels, parabolic troughs, or linear Fresnel systems. MSTL provides realistic conditions similar to a portion of a concentrating solar power facility. The facility currently uses 60/40 nitrate %E2%80%9Csolar salt%E2%80%9D and can circulate the salt at pressure up to 40 bar (600psi), temperature to 585%C2%B0C, and flow rate of 44-50kg/s(400-600GPM) depending on temperature. The purpose of this document is to provide a basis for customers to evaluate the applicability to their testing needs, and to provide an outline of expectations for conducting testing on MSTL. The document can serve as the basis for testing agreements including Work for Others (WFO) and Cooperative Research and Development Agreements (CRADA). While this document provides the basis for these agreements and describes some of the requirements for testing using MSTL and on the site at Sandia, the document is not sufficient by itself as a test agreement. The document, however, does provide customers with a uniform set of information to begin the test planning process.

  7. 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....

  8. 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

  9. Cathode solid electrolyte interface’s function originated from salt type additives in lithium ion batteries

    International Nuclear Information System (INIS)

    Kaneko, Yu; Park, Juyeon; Yokotsuji, Hokuto; Odawara, Makoto; Takase, Hironari; Ue, Makoto; Lee, Maeng-Eun

    2016-01-01

    Highlights: • Our chemical analysis determines the important functional groups of cathode’s solid electrolyte interface originated from salt type additives. • Our quantum chemical calculation reveals the redox character of the additives and their candidate chemical components of the solid electrolyte interface. • Our molecular dynamics simulation reproduces the selective lithium ion translocation and protective layer formation as the solid electrolyte interface function. - Abstract: This is the study about the cathode’s solid electrolyte interface (SEI) formation mechanism of salt type additives (STAs) and its function. To address this issue, we performed several types of chemical analysis and computer simulation techniques. In order to reveal the redox nature and oxidative decomposition dynamics, the electrolyte (EL) solution dynamics by Quantum mechanics and Molecular mechanics (QM/MM) method was applied. The estimation of SEI chemical components agrees with our chemical analyses data and other group’s reports. The molecular dynamics simulation of sub micro second sampling indicates that the SEI phase induced from STAs functions as a lithium ion selective translocation media and protective coating layer against the degradation of the solvent molecules. The results give us an insight how to design additive’s chemical structure to improve longevity of the cell in the high voltage regime.

  10. 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.

  11. Effect of water in salt repositories. Final report

    International Nuclear Information System (INIS)

    Baes, C.F. Jr.; Gilpatrick, L.O.; Kitts, F.G.; Bronstein, H.R.; Shor, A.J.

    1983-09-01

    Additional results confirm that during most of the consolidation of polycrystalline salt in brine, the previously proposed rate expression applies. The final consolidation, however, proceeds at a lower rate than predicted. The presence of clay hastens the consolidation process but does not greatly affect the previously observed relationship between permeability and void fraction. Studies of the migration of brine within polycrystalline salt specimens under stress indicate that the principal effect is the exclusion of brine as a result of consolidation, a process that evidently can proceed to completion. No clear effect of a temperature gradient could be identified. A previously reported linear increase with time of the reciprocal permeability of salt-crystal interfaces to brine was confirmed, though the rate of increase appears more nearly proportional to the product of sigma ΔP rather than sigma ΔP 2 (sigma is the uniaxial stress normal to the interface and ΔP is the hydraulic pressure drop). The new results suggest that a limiting permeability may be reached. A model for the permeability of salt-crystal interfaces to brine is developed that is reasonably consistent with the present results and may be used to predict the permeability of bedded salt. More measurements are needed, however, to choose between two limiting forms of the model

  12. Effect of water in salt repositories. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Baes, C.F. Jr.; Gilpatrick, L.O.; Kitts, F.G.; Bronstein, H.R.; Shor, A.J.

    1983-09-01

    Additional results confirm that during most of the consolidation of polycrystalline salt in brine, the previously proposed rate expression applies. The final consolidation, however, proceeds at a lower rate than predicted. The presence of clay hastens the consolidation process but does not greatly affect the previously observed relationship between permeability and void fraction. Studies of the migration of brine within polycrystalline salt specimens under stress indicate that the principal effect is the exclusion of brine as a result of consolidation, a process that evidently can proceed to completion. No clear effect of a temperature gradient could be identified. A previously reported linear increase with time of the reciprocal permeability of salt-crystal interfaces to brine was confirmed, though the rate of increase appears more nearly proportional to the product of sigma ..delta..P rather than sigma ..delta..P/sup 2/ (sigma is the uniaxial stress normal to the interface and ..delta..P is the hydraulic pressure drop). The new results suggest that a limiting permeability may be reached. A model for the permeability of salt-crystal interfaces to brine is developed that is reasonably consistent with the present results and may be used to predict the permeability of bedded salt. More measurements are needed, however, to choose between two limiting forms of the model.

  13. 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

  14. High-Order Finite-Difference Solution of the Poisson Equation with Interface Jump Conditions II

    Science.gov (United States)

    Marques, Alexandre; Nave, Jean-Christophe; Rosales, Rodolfo

    2010-11-01

    The Poisson equation with jump discontinuities across an interface is of central importance in Computational Fluid Dynamics. In prior work, Marques, Nave, and Rosales have introduced a method to obtain fourth-order accurate solutions for the constant coefficient Poisson problem. Here we present an extension of this method to solve the variable coefficient Poisson problem to fourth-order of accuracy. The extended method is based on local smooth extrapolations of the solution field across the interface. The extrapolation procedure uses a combination of cubic Hermite interpolants and a high-order representation of the interface using the Gradient-Augmented Level-Set technique. This procedure is compatible with the use of standard discretizations for the Laplace operator, and leads to modified linear systems which have the same sparsity pattern as the standard discretizations. As a result, standard Poisson solvers can be used with only minimal modifications. Details of the method and applications will be presented.

  15. 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.

  16. Infrared Spectroscopy as Molecular Probe of the Macroscopic Metal-Liquid Interface

    Directory of Open Access Journals (Sweden)

    Johannes Kiefer

    2017-11-01

    Full Text Available Metal-liquid interfaces are of the utmost importance in a number of scientific areas, including electrochemistry and catalysis. However, complicated analytical methods and sample preparation are usually required to study the interfacial phenomena. We propose an infrared spectroscopic approach that enables investigating the molecular interactions at the interface, but needing only minimal or no sample preparation. For this purpose, the internal reflection element (IRE is wetted with a solution as first step. Second, a small plate of the metal of interest is put on top and pressed onto the IRE. The tiny amount of liquid that is remaining between the IRE and the metal is sufficient to produce an IR spectrum with good signal to noise ratio, from which information about molecular interactions, such as hydrogen bonding, can be deduced. Proof-of-concept experiments were carried out with aqueous salt and acid solutions and an aluminum plate.

  17. Characterization of solid-solution interface by potentiometric titration and electrophoretic mobility

    International Nuclear Information System (INIS)

    Lindecker, C.; Drot, R.; Fourest, B.; Simoni, E.

    1999-01-01

    The study of nuclear waste storage in deep geological sites involves the understanding of processes which could produce a possible dispersion or retention of radioelements. The dispersion of solid particles in aqueous solution is consequently important to be characterized. In this bi-phased system it is necessary to determine the characteristics of the solid-solution interface. The method used of this study is the techniques of potentiometric titration applied to heterogeneous systems. The material studied were phosphate matrices which were synthesized in the laboratory. The dependence of their surface change upon the nature of the electrolytes was investigated

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. Theory of the formation of the electric double layer at the ion exchange membrane-solution interface.

    Science.gov (United States)

    Moya, A A

    2015-02-21

    This work aims to extend the study of the formation of the electric double layer at the interface defined by a solution and an ion-exchange membrane on the basis of the Nernst-Planck and Poisson equations, including different values of the counter-ion diffusion coefficient and the dielectric constant in the solution and membrane phases. The network simulation method is used to obtain the time evolution of the electric potential, the displacement electric vector, the electric charge density and the ionic concentrations at the interface between a binary electrolyte solution and a cation-exchange membrane with total co-ion exclusion. The numerical results for the temporal evolution of the interfacial electric potential and the surface electric charge are compared with analytical solutions derived in the limit of the shortest times by considering the Poisson equation for a simple cationic diffusion process. The steady-state results are justified from the Gouy-Chapman theory for the diffuse double layer in the limits of similar and high bathing ionic concentrations with respect to the fixed-charge concentration inside the membrane. Interesting new physical insights arise from the interpretation of the process of the formation of the electric double layer at the ion exchange membrane-solution interface on the basis of a membrane model with total co-ion exclusion.

  4. 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.

  5. 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.

  6. 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

  7. Study of solute segregation at interfaces using Auger electron spectroscopy

    International Nuclear Information System (INIS)

    White, C.L.

    1984-01-01

    Interfacial segregation, often confined to within a few atomic distances of the interface, can strongly influence the processing and properties of metals and ceramics. The thinness of such solute-enriched regions can cause them to be particularly suitable for study using surface sensitive microanalytical techniques such as Auger electron spectroscopy (AES). The application of AES to studies of interfacial segregation in metals and ceramics is briefly reviewed, and several examples are presented. 43 references, 14 figures

  8. Pseudomacrocyclic effect in extraction processes of metal salts by polyethers from nitric acid solutions

    International Nuclear Information System (INIS)

    Yakshin, V.V.; Vilkova, O.M.; Kotlyar, S.A.; Kamalov, G.L.

    1997-01-01

    Comparison of macrocyclic (ME) and pseudmacrocyclic effects (PME), originating by conduct of the metal salt extraction processes (Cs, Sr, In, Zr, Cd, etc) from nitric acid solutions through linear and cyclic polyethers, containing 5 or 6 atoms of ether oxygen and having close molecular masses (290-360), is carried out. It is shown that ordinary ethers practically do not extract the studied metals from nitric acid solutions. By transfer from linear polyethers to their macrocyclic analogs the ME impact is expressed clearly enough: the separation coefficient value grows by tens and hundred times. At the some time the PME role in the extraction processes of metal nitrates through crown-ethers with alkyl and groups is expressed less clearly

  9. 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

  10. 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.

  11. Spontaneous grafting of diazonium salts: chemical mechanism on metallic surfaces.

    Science.gov (United States)

    Mesnage, Alice; Lefèvre, Xavier; Jégou, Pascale; Deniau, Guy; Palacin, Serge

    2012-08-14

    The spontaneous reaction of diazonium salts on various substrates has been widely employed since it consists of a simple immersion of the substrate in the diazonium salt solution. As electrochemical processes involving the same diazonium salts, the spontaneous grafting is assumed to give covalently poly(phenylene)-like bonded films. Resistance to solvents and to ultrasonication is commonly accepted as indirect proof of the existence of a covalent bond. However, the most relevant attempts to demonstrate a metal-C interface bond have been obtained by an XPS investigation of spontaneously grafted films on copper. Similarly, our experiments give evidence of such a bond in spontaneously grafted films on nickel substrates in acetonitrile. In the case of gold substrates, the formation of a spontaneous film was unexpected but reported in the literature in parallel to our observations. Even if no interfacial bond was observed, formation of the films was explained by grafting of aryl cations or radicals on the surface arising from dediazoniation, the film growing later by azo coupling, radical addition, or cationic addition on the grafted phenyl layer. Nevertheless, none of these mechanisms fits our experimental results showing the presence of an Au-N bond. In this work, we present a fine spectroscopic analysis of the coatings obtained on gold and nickel substrates that allow us to propose a chemical structure of such films, in particular, their interface with the substrates. After testing the most probable mechanisms, we have concluded in favor of the involvement of two complementary mechanisms which are the direct reaction of diazonium salts with the gold surface that accounts for the observed Au-N interfacial bonds as well as the formation of aryl cations able to graft on the substrate through Au-C linkages.

  12. Can mothers safely prepare labon-gur salt-sugar solution after demonstration in a diarrhoeal hospital?

    DEFF Research Database (Denmark)

    Islam, M A; Kofoed, Poul-Erik; Begum, S

    1992-01-01

    Home-based salt-sugar solution (SSS) prepared with labon (locally produced sea salt) and gur (unrefined brown sugar) has been recommended as a cheap, locally available and a simple tool to prevent and treat diarrhoeal dehydration. Preparation of labon-gur SSS is demonstrated to the patients...... and the attendants at ICDDR, Bangladesh. To evaluate performances, 150 mothers were asked to measure labon and gur by finger pinch and first method and 100 mothers measured half a seer of water to prepare labon-gur SSS, shortly after the demonstration sessions. 4.0% of the samples exceeded the upper safety limit...... this knowledge. Our study suggests that demonstration of home-based SSS in a diarrhoeal hospital may positively affect health education and that health personnel should actively participate in increasing health awareness....

  13. Biomimetic synthesis and morphological control of metal carbonates at the air/solution interface

    International Nuclear Information System (INIS)

    Lee, Shichoon; Cho, Kilwon; Son, Younggon

    2012-01-01

    Biomimetic approaches can provide a means of fabricating nanostructured materials under environmentally benign conditions. In this paper, we synthesized metal carbonate films, such as calcite, strontianite, malachite, and hydrozincite films, at the air-solution interface of solutions containing corresponding metal ions by using inflowing CO 2 from the atmosphere. The addition of acidic polymers, fulfilling the role of an acidic protein in biomineralization, provided CaCO 3 nanofibers, SrCO 3 nanofibers oriented in a specific direction, and copper carbonate and zinc carbonate hydroxide thin films. The metal carbonates prepared in this study were used as precursors for the formation of metal oxide nanocrystals via pyrolysis. This work showed that various metal carbonates and metal oxides with nanostructures can be prepared by using atmospheric CO 2 . - Highlights: ► Biomimetic synthesis of metal carbonate nanofilms at the air/solution interface. ► The reaction between metal ions and carbonate ions derived from CO 2 in the air. ► Calcium, strontium, copper and zinc carbonates were formed. ► The morphologies of the nanofilms were controlled by adding the acidic polymer. ► Nanostructured metal oxides were prepared by pyrolysis of the metal carbonates.

  14. Molecular dynamics study of structure and vibrational spectra at zwitterionoic lipid/aqueous KCl, NaCl, and CaCl2 solution interfaces

    Science.gov (United States)

    Ishiyama, Tatsuya; Shirai, Shinnosuke; Okumura, Tomoaki; Morita, Akihiro

    2018-06-01

    Molecular dynamics (MD) simulations of KCl, NaCl, and CaCl2 solution/dipalmytoylphosphatidylcholine lipid interfaces were performed to analyze heterodyne-detected vibrational sum frequency generation (HD-VSFG) spectra in relation to the interfacial water structure. The present MD simulation well reproduces the experimental spectra and elucidates a specific cation effect on the interfacial structure. The K+, Na+, and Ca2+ cation species penetrate in the lipid layer more than the anions in this order, due to the electrostatic interaction with negative polar groups of lipid, and the electric double layer between the cations and anions cancels the intrinsic orientation of water at the water/lipid interface. These mechanisms explain the HD-VSFG spectrum of the water/lipid interface and its spectral perturbation by adding the ions. The lipid monolayer reverses the order of surface preference of the cations at the solution/lipid interface from that at the solution/air interface.

  15. Metallurgical electrochemistry: the interface between materials science and molten salt chemistry

    International Nuclear Information System (INIS)

    Sadoway, D.R.

    1991-01-01

    Even though molten salt electrolysis finds application in the primary extraction of metals (electrowinning), the purification and recycling of metals (electrorefining), and in the formation of metal coatings (electroplating), the technology remains in many respects underexploited. Electrolysis in molten salts as well as other nonaqueous media has enormous potential for materials processing. First, owing to the special attributes of nonaqueous electrolytes electrochemical processing in these media has an important role to play in the generation of advanced materials, i.e., materials with specialized chemistries or tailored microstructures (electrosynthesis). Secondly, as environmental quality standards rise beyond the capabilities of classical metals extraction technologies to comply, molten salt electrolysis may prove to be the only acceptable route from ore to metal. Growing public awareness of pollution from the metals industry could stimulate a renaissance in molten salt electrochemistry. Challenges facing metallurgical electrochemistry as relates to the environment fall into two categories: (1) improving existing electrochemical technology, and (2) developing clean electrochemical technology to displace current nonelectrochemical technology. In both instances success hinges upon the discovery of advanced materials and the ecologically sound extraction of metals, the close coupling between materials science and molten salt chemistry is manifest. (author) 6 refs

  16. Brain-computer interfaces for EEG neurofeedback: peculiarities and solutions.

    Science.gov (United States)

    Huster, René J; Mokom, Zacharais N; Enriquez-Geppert, Stefanie; Herrmann, Christoph S

    2014-01-01

    Neurofeedback training procedures designed to alter a person's brain activity have been in use for nearly four decades now and represent one of the earliest applications of brain-computer interfaces (BCI). The majority of studies using neurofeedback technology relies on recordings of the electroencephalogram (EEG) and applies neurofeedback in clinical contexts, exploring its potential as treatment for psychopathological syndromes. This clinical focus significantly affects the technology behind neurofeedback BCIs. For example, in contrast to other BCI applications, neurofeedback BCIs usually rely on EEG-derived features with only a minimum of additional processing steps being employed. Here, we highlight the peculiarities of EEG-based neurofeedback BCIs and consider their relevance for software implementations. Having reviewed already existing packages for the implementation of BCIs, we introduce our own solution which specifically considers the relevance of multi-subject handling for experimental and clinical trials, for example by implementing ready-to-use solutions for pseudo-/sham-neurofeedback. © 2013.

  17. THERMODYNAMIC PROPERTIES OF NONAQUEOUS SINGLE SALT SOLUTIONS USING THE Q-ELECTROLATTICE EQUATION OF STATE

    Directory of Open Access Journals (Sweden)

    A. Zuber

    2015-09-01

    Full Text Available AbstractThe correlation of thermodynamic properties of nonaqueous electrolyte solutions is relevant to design and operation of many chemical processes, as in fertilizer production and the pharmaceutical industry. In this work, the Q-electrolattice equation of state (EOS is used to model vapor pressure, mean ionic activity coefficient, osmotic coefficient, and liquid density of sixteen methanol and ten ethanol solutions containing single strong 1:1 and 2:1 salts. The Q-electrolattice comprises the lattice-based Mattedi-Tavares-Castier (MTC EOS, the Born term and the explicit MSA term. The model requires two adjustable parameters per ion, namely the ionic diameter and the solvent-ion interaction energy. Predictions of osmotic coefficient at 298.15 K and liquid density at different temperatures are also presented.

  18. Conductometric investigation of salt-free solutions of polyriboguanylic acid. Issledovanie bessolevykh rastvorov poliriboguanilovoj kisloty metodom konduktometrii

    Energy Technology Data Exchange (ETDEWEB)

    Kozlov, A G; Davydova, O V; Kargov, S I [Moskovskij Gosudarstvennyj Univ., Moscow (Russian Federation). Khimicheskij Fakul' tet

    1993-08-01

    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[sub 4][sup +]-, Rb[sup +]-, K[sup +]-, Na[sup +]-, the second one - Cs[sup +]-, and Li[sup +]-poly(G). The assumption is made that Li[sup +] and Cs[sup +] 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.

  19. 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

  20. Field effects in graphene in an interface contact with aqueous solutions of acetic acid and potassium hydroxide

    Science.gov (United States)

    Butko, A. V.; Butko, V. Yu.; Lebedev, S. P.; Lebedev, A. A.; Kumzerov, Yu. A.

    2017-10-01

    For the creation of new promising chemical sensors, it is very important to study the influence of the interface between graphene and aqueous solutions of acids and alkalis on the transistor characteristics of graphene. Transistor structures on the basis of graphene grown by thermal decomposition of silicon carbide were created and studied. For the interface of graphene with aqueous solutions of acetic acid and potassium hydroxide in the transistor geometry, with a variation in the gate-to-source voltage, the field effect corresponding to the hole type of charge carriers in graphene was observed. It is established that an increase in the concentration of molecular ions in these solutions leads to an increase in the dependence of the resistance of the transistor on the gate voltage.

  1. 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

  2. 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.

  3. 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

  4. Structure and thermodynamics of molten salts

    International Nuclear Information System (INIS)

    Papatheodorou, G.N.

    1983-01-01

    This chapter investigates single-component molten salts and multicomponent salt mixtures. Molten salts provide an important testing ground for theories of liquids, solutions, and plasmas. Topics considered include molten salts as liquids (the pair potential, the radial distribution function, methods of characterization), single salts (structure, thermodynamic correlations), and salt mixtures (the thermodynamics of mixing; spectroscopy and structure). Neutron and X-ray scattering techniques are used to determine the structure of molten metal halide salts. The corresponding-states theory is used to obtain thermodynamic correlations on single salts. Structural information on salt mixtures is obtained by using vibrational (Raman) and electronic absorption spectroscopy. Charge-symmetrical systems and charge-unsymmetrical systems are used to examine the thermodynamics of salt mixtures

  5. 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

  6. Additional disinfection with a modified salt solution in a root canal model.

    Science.gov (United States)

    van der Waal, Suzette V; Oonk, Charlotte A M; Nieman, Selma H; Wesselink, Paul R; de Soet, Johannes J; Crielaard, Wim

    2015-10-01

    The aim of this study is to investigate the disinfecting properties of a modified salt solution (MSS) and calcium hydroxide (Ca(OH)2) in a non-direct-contact ex-vivo model. Seventy-four single-canal roots infected with Enterococcus faecalis were treated with 1% sodium hypochlorite (NaOCl) irrigation or with NaOCl irrigation with subsequent dressing with MSS or Ca(OH)2. After removal of the dressings, the roots were filled with bacterial growth medium and incubated for seven days to enable the surviving bacteria to repopulate the root canal lumen. Growth was determined by sampling the root canals with paper points before treatment (S1), after treatment (S2) and incubation after treatment (S3). The colony forming units were counted at S1 and S2. At S3, growth was determined as no/yes regrowth. The Kruskal-Wallis, McNemar and χ(2) test were used for statistical analyses. At S2, in the NaOCl group, growth was found in 5 of 19 root canals. After the removal of MSS or Ca(OH)2 bacteria were retrieved from one root canal in both groups. At S3, repopulation of the root canals had occurred in 14 of 19 roots after sole NaOCl irrigation, 6 of 20 roots after MSS-dressing and in 14 of 20 roots after Ca(OH)2-dressing. MSS was more effective in preventing regrowth than Ca(OH)2 (P=0.009). The modified salt solution prevented regrowth in roots which indicates that it can eliminate persistent bacteria. Dressing the root canals with Ca(OH)2 did not provide additional disinfection after NaOCl irrigation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Numerical analysis of impurity separation from waste salt by investigating the change of concentration at the interface during zone refining process

    Science.gov (United States)

    Choi, Ho-Gil; Shim, Moonsoo; Lee, Jong-Hyeon; Yi, Kyung-Woo

    2017-09-01

    The waste salt treatment process is required for the reuse of purified salts, and for the disposal of the fission products contained in waste salt during pyroprocessing. As an alternative to existing fission product separation methods, the horizontal zone refining process is used in this study for the purification of waste salt. In order to evaluate the purification ability of the process, three-dimensional simulation is conducted, considering heat transfer, melt flow, and mass transfer. Impurity distributions and decontamination factors are calculated as a function of the heater traverse rate, by applying a subroutine and the equilibrium segregation coefficient derived from the effective segregation coefficients. For multipass cases, 1d solutions and the effective segregation coefficient obtained from three-dimensional simulation are used. In the present study, the topic is not dealing with crystal growth, but the numerical technique used is nearly the same since the zone refining technique was just introduced in the treatment of waste salt from nuclear power industry because of its merit of simplicity and refining ability. So this study can show a new application of single crystal growth techniques to other fields, by taking advantage of the zone refining multipass possibility. The final goal is to achieve the same high degree of decontamination in the waste salt as in zone freezing (or reverse Bridgman) method.

  8. 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

  9. Cumulates, Dykes and Pressure Solution in the Ice-Salt Mantle of Europa: Geological Consequences of Pressure Dependent Liquid Compositions and Volume Changes During Ice-Salt Melting Reactions.

    Science.gov (United States)

    Day, S.; Asphaug, E.; Bruesch, L.

    2002-12-01

    Water-salt analogue experiments used to investigate cumulate processes in silicate magmas, along with observations of sea ice and ice shelf behaviour, indicate that crystal-melt separation in water-salt systems is a rapid and efficient process even on scales of millimetres and minutes. Squeezing-out of residual melts by matrix compaction is also predicted to be rapid on geological timescales. We predict that the ice-salt mantle of Europa is likely to be strongly stratified, with a layered structure predictable from density and phase relationships between ice polymorphs, aqueous saline solutions and crystalline salts such as hydrated magnesium sulphates (determined experimentally by, inter alia, Hogenboom et al). A surface layer of water ice flotation cumulate will be separated from denser salt cumulates by a cotectic horizon. This cotectic horizon will be both the site of subsequent lowest-temperature melting and a level of neutral buoyancy for the saline melts produced. Initial melting will be in a narrow depth range owing to increasing melting temperature with decreasing pressure: the phase relations argue against direct melt-though to the surface unless vesiculation occurs. Overpressuring of dense melts due to volume expansion on cotectic melting is predicted to lead to lateral dyke emplacement and extension above the dyke tips. Once the liquid leaves the cotectic, melting of water ice will involve negative volume change. Impact-generated melts will drain downwards through the fractured zones beneath crater floors. A feature in the complex crater Mannan'an, with elliptical ring fractures around a conical depression with a central pit, bears a close resemblance to Icelandic glacier collapse cauldrons produced by subglacial eruptions. Other structures resembling Icelandic cauldrons occur along Europan banded structures, while resurgence of ice rubble within collapse structures may produce certain types of chaos region. More general contraction of the ice mantle

  10. 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)

  11. 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

  12. Physico-Chemical Study of the Separation of Calcium Isotopes by Chemical Exchange Between Amalgam and Salt Solutions

    International Nuclear Information System (INIS)

    Duie, P.; Dirian, G.

    1962-01-01

    In a preliminary study of the isotopic exchange between Ca amalgam and aqueous or organic solutions of Ca salts, the main parameters governing the feasibility of a separation process based on these systems such as separation factor, exchange kinetics, rate of decomposition of the amalgam were investigated. The separation factor between 40 Ca and 46 Ca was found to be of the order of 1.02. The rate of the exchange reaction is rather low for aqueous solutions, extremely low for organic solutions. The amalgam seems not to be attacked by dimethyl-formamide solutions; but it is rapidly decomposed by aqueous solutions of Ca halides. This decomposition is slow in the case of aqueous solutions of calcium formate and still slower for Ca(OH) 2 ; however, except in particular conditions, the observed rate is often much higher, owing to interfering reactions between amalgam and water vapor contained in H 2 bubbles. (authors) [fr

  13. Japanese traditional miso soup attenuates salt-induced hypertension and its organ damage in Dahl salt-sensitive rats.

    Science.gov (United States)

    Yoshinaga, Mariko; Toda, Natsuko; Tamura, Yuki; Terakado, Shouko; Ueno, Mai; Otsuka, Kie; Numabe, Atsushi; Kawabata, Yukari; Uehara, Yoshio

    2012-09-01

    We investigated the effects of long-term miso soup drinking on salt-induced hypertension in Dahl salt-sensitive (Dahl S) rats. Dahl S rats were divided into four groups that consumed 1) water, 2) a 0.9% NaCl solution, 3) a 1.3% sodium NaCl solution, or 4) miso soup containing 1.3% NaCl. They were followed for 8 wk. Systolic blood pressure and hypertensive organ damage were determined. Systolic blood pressure increased in an age- and dose-dependent manner in Dahl S rats drinking salt solutions. The systolic blood pressure increase was significantly less in the Dahl S rats that drank miso soup, although the ultimate cumulative salt loading was greater than that in the Dahl S rats given the 1.3% NaCl solution. This blood pressure decrease was associated with a morphologic attenuation of glomerular sclerosis in the kidney and collagen infiltration in the heart. Urinary protein excretions were less in the miso group than in the rats given the 1.3% NaCl solution. The fractional excretion of sodium was increased and that of potassium was decreased in Dahl S rats given the 1.3% NaCl solution, and these effects were reversed in rats given miso soup toward the values of the control. We found that long-term miso soup drinking attenuates the blood pressure increase in salt-induced hypertension with organ damage. This may be caused by a possible retardation of sodium absorption in the gastrointestinal tract or by the direct effects of nutrients in the miso soup from soybeans. The decrease was associated with decreases in cardiovascular and renal damage. Copyright © 2012 Elsevier Inc. All rights reserved.

  14. Soft X-ray absorption spectra of aqueous salt solutions with highly charged cations in liquid microjets

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, Craig P.; Uejio, Janel S.; Duffin, Andrew M.; Drisdell, Walter S.; Smith, Jared D.; Saykally, Richard J.

    2010-03-11

    X-ray absorption spectra of 1M aqueous solutions of indium (III) chloride, yttrium (III) bromide, lanthanum (III) chloride, tin (IV) chloride and chromium (III) chloride have been measured at the oxygen K-edge. Relatively minor changes are observed in the spectra compared to that of pure water. SnCl{sub 4} and CrCl{sub 3} exhibit a new onset feature which is attributed to formation of hydroxide or other complex molecules in the solution. At higher energy, only relatively minor, but salt-specific changes in the spectra occur. The small magnitude of the observed spectral changes is ascribed to offsetting perturbations by the cations and anions.

  15. Comparative study of solute trapping and Gibbs free energy changes at the phase interface during alloy solidification under local nonequilibrium conditions

    Energy Technology Data Exchange (ETDEWEB)

    Sobolev, S. L., E-mail: sobolev@icp.ac.ru [Russian Academy of Sciences, Institute of Problems of Chemical Physics (Russian Federation)

    2017-03-15

    An analytical model has been developed to describe the influence of solute trapping during rapid alloy solidification on the components of the Gibbs free energy change at the phase interface with emphasis on the solute drag energy. For relatively low interface velocity V < V{sub D}, where V{sub D} is the characteristic diffusion velocity, all the components, namely mixing part, local nonequilibrium part, and solute drag, significantly depend on solute diffusion and partitioning. When V ≥ V{sub D}, the local nonequilibrium effects lead to a sharp transition to diffusionless solidification. The transition is accompanied by complete solute trapping and vanishing solute drag energy, i.e. partitionless and “dragless” solidification.

  16. Measurement and evaluation of the water and the salt solutions occurring in the exploitation of rock salt, potash or copper shale deposits in the Bernburg Hauptsattel or the Sangerhaeuser Revier in order to assess the long-term safety of repositories

    International Nuclear Information System (INIS)

    Schwandt, A.

    1993-01-01

    For a thorough assessment of conditions governing the occurrence of salt solutions or water in a repository in the Zechstein, i.e. in the salt formation and at its boundaries, data measured in other mines developed in this formation can yield valuable information. The studies reported were based on geological, hydrogeological, geochemical and geomechanical data collected for more than 50 inflow areas or salt solution bearing areas, covering approx. 15,000 chemical or physical analyses from which the data were derived describing the characteristics or development of inflow streams with time. In addition, the mapped inflow streams were evaluated with a view to the geological and hydrogeological and the geomechanical conditions of origin, as well as engineering impacts. (DG) [de

  17. Molten salt hazardous waste disposal process utilizing gas/liquid contact for salt recovery

    International Nuclear Information System (INIS)

    Grantham, L.F.; McKenzie, D.E.

    1984-01-01

    The products of a molten salt combustion of hazardous wastes are converted into a cooled gas, which can be filtered to remove hazardous particulate material, and a dry flowable mixture of salts, which can be recycled for use in the molten salt combustion, by means of gas/liquid contact between the gaseous products of combustion of the hazardous waste and a solution produced by quenching the spent melt from such molten salt combustion. The process results in maximizing the proportion of useful materials recovered from the molten salt combustion and minimizing the volume of material which must be discarded. In a preferred embodiment a spray dryer treatment is used to achieve the desired gas/liquid contact

  18. Test procedures for salt rock

    International Nuclear Information System (INIS)

    Dusseault, M.B.

    1985-01-01

    Potash mining, salt mining, design of solution caverns in salt rocks, disposal of waste in salt repositories, and the use of granular halite backfill in underground salt rock mines are all mining activities which are practised or contemplated for the near future. Whatever the purpose, the need for high quality design parameters is evident. The authors have been testing salt rocks in the laboratory in a number of configurations for some time. Great care has been given to the quality of sample preparation and test methodology. This paper describes the methods, presents the elements of equipment design, and shows some typical results

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

    Science.gov (United States)

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

    2001-03-01

    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 tap water formed insoluble matters. This 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 molecule of the active coagulation component in MOC-SC-PC and form a net-like structure. The coagulation mechanism of MOC-SC-PC seemed to be an enmeshment of Kaolin by the insoluble matters with the net-like structure. In case of Ca2+ ion (bivalent cations), at least 0.2 mM was necessary for coagulation at 0.3 mgC l-1 dose of MOC-SC-PC. Other coagulation mechanisms like compression of double layer, interparticle bridging or charge neutralization were not responsible for the coagulation by MOC-SC-PC.

  20. Optogenetic Inhibition of Ventral Pallidum Neurons Impairs Context-Driven Salt Seeking.

    Science.gov (United States)

    Chang, Stephen E; Smedley, Elizabeth B; Stansfield, Katherine J; Stott, Jeffrey J; Smith, Kyle S

    2017-06-07

    Salt appetite, in which animals can immediately seek out salt when under a novel state of sodium deprivation, is a classic example of how homeostatic systems interface with learned associations to produce an on-the-fly updating of motivated behavior. Neural activity in the ventral pallidum (VP) has been shown to encode changes in the value of salt under such conditions, both the value of salt itself (Tindell et al., 2006) and the motivational value of its predictive cues (Tindell et al., 2009; Robinson and Berridge, 2013). However, it is not known whether the VP is necessary for salt appetite in terms of seeking out salt or consuming salt following sodium depletion. Here, we used a conditioned place-preference procedure to investigate the effects of optogenetically inhibiting the VP on context-driven salt seeking and the consumption of salt following deprivation. Male rats learned to associate one context with sucrose and another context with less-desirable salt. Following sodium depletion, and in the absence of either sucrose or salt, we found that inhibiting the VP selectively reduced the elevation in time spent in the salt-paired context. VP inhibition had minimal effects on the consumption of salt once it was made available. To our knowledge, this is the first evidence that the VP or any brain region is necessary for the ability to use contextual cues to guide salt seeking. These results highlight a dissociation between deficit-driven reward seeking and reward consumption to replenish those deficits, with the former process being particularly sensitive to on-line VP activity. SIGNIFICANCE STATEMENT Salt appetite, in which rats will immediately seek out a once-undesirable concentrated salt solution after being depleted of bodily sodium despite never having tasted salt as a positive reward, is a phenomenon showing how animals can update their motivational goals without any new learning or conditioning. This salt-seeking behavior is also observed when the animal

  1. 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.

  2. RiceMetaSys for salt and drought stress responsive genes in rice: a web interface for crop improvement.

    Science.gov (United States)

    Sandhu, Maninder; Sureshkumar, V; Prakash, Chandra; Dixit, Rekha; Solanke, Amolkumar U; Sharma, Tilak Raj; Mohapatra, Trilochan; S V, Amitha Mithra

    2017-09-30

    Genome-wide microarray has enabled development of robust databases for functional genomics studies in rice. However, such databases do not directly cater to the needs of breeders. Here, we have attempted to develop a web interface which combines the information from functional genomic studies across different genetic backgrounds with DNA markers so that they can be readily deployed in crop improvement. In the current version of the database, we have included drought and salinity stress studies since these two are the major abiotic stresses in rice. RiceMetaSys, a user-friendly and freely available web interface provides comprehensive information on salt responsive genes (SRGs) and drought responsive genes (DRGs) across genotypes, crop development stages and tissues, identified from multiple microarray datasets. 'Physical position search' is an attractive tool for those using QTL based approach for dissecting tolerance to salt and drought stress since it can provide the list of SRGs and DRGs in any physical interval. To identify robust candidate genes for use in crop improvement, the 'common genes across varieties' search tool is useful. Graphical visualization of expression profiles across genes and rice genotypes has been enabled to facilitate the user and to make the comparisons more impactful. Simple Sequence Repeat (SSR) search in the SRGs and DRGs is a valuable tool for fine mapping and marker assisted selection since it provides primers for survey of polymorphism. An external link to intron specific markers is also provided for this purpose. Bulk retrieval of data without any limit has been enabled in case of locus and SSR search. The aim of this database is to facilitate users with a simple and straight-forward search options for identification of robust candidate genes from among thousands of SRGs and DRGs so as to facilitate linking variation in expression profiles to variation in phenotype. Database URL: http://14.139.229.201.

  3. Influence of interface reactions on the YBCO films grown by fluorine-free solution route

    DEFF Research Database (Denmark)

    Zhao, Yue; Wu, Wei; Tang, Xiao

    2015-01-01

    Fabrication of full-stacked coated conductors by all-chemical-solution routes exhibit a great potential in view of further reducing the cost and increasing the throughput for industrialization. Growth of YBa2Cu3O7−x (YBCO) superconducting films by fluorine-free metal organic deposition routes (FF......-MOD) which are environmental friendly has attracted more attentions recently. In this work, comparison study was performed on the YBCO-Ag superconducting thin films deposited on two types of single crystal substrates, LaAlO3 and Ce0.9La0.9O2−y/YSZ. The structural characterization and superconducting...... properties studies reveal that the interface reactions between the YBCO-Ag film and the CLO cap layer play an essential role on the nucleation and growth of YBCO-Ag films from the FF solution. Weak texture caused by serious interface reactions at high growth temperature is the main explanations for the poor...

  4. Adsorption of asparagine on the gold electrode and air/solution interface

    International Nuclear Information System (INIS)

    Slojkowska, R.; Palys, B.; Jurkiewicz-Herbich, M.

    2004-01-01

    The adsorption of asparagine (Asn) on a gold electrode from 0.1 M LiClO 4 aqueous solutions was investigated. The experimental data obtained from ac impedance measurements were analyzed to determine the dependence of adsorption parameters, i.e. the standard Gibbs energy of adsorption (ΔG 0 ), maximal value of surface excess concentration (Γ max ) of Asn and parameter of interactions in the adsorbed layer (A) on the electrode potential. The relatively large value of Gibbs energy of adsorption (∼ -47 kJ mol -1 ) gives the evidence of a very strong adsorption of Asn at the polycrystalline Au electrode. The comparison of the adsorption behavior of Asn at the air/solution and the Au/solution interfaces points out to the significant electronic interactions of adsorbate molecules with the Au electrode, since the adsorption of Asn on a free surface (from the same solutions) is very week. The analysis of the electrochemical data as well as the infrared reflection absorption spectroscopy (IRAS) results reveal that Asn molecules are anchored to the Au surface through oxygen atoms of the carboxylate group COO - and through the amide carbonyl group

  5. Ionic structure of solutions of alkali metals and molten salts

    International Nuclear Information System (INIS)

    Chabrier, G.; Senatore, G.; Tosi, M.P.

    1982-02-01

    Neutron diffraction patterns from K-KCl and Rb-RbBr liquid solutions at various compositions are examined in an ionic-mixture model which neglects screening and aggregation due to the metallic electrons. The main feature of the observed diffraction patterns for wave number k above roughly 1A -1 are accounted for by the model. The approach to the metal-rich end of the phase diagram is analyzed in detail from different viewpoints in the K-KCl system. Short-range correlations of the potassium ions are described in this region by a metallic radius deduced from properties of the pure liquid metal, but a simple expanded-metal model must be supplemented by the assumption that considerable disorder is introduced in its structure by the halogen ions. Features of short-range ordering in the salt-rich region that are implied by a shoulder on the high-k side of the main peak in the diffraction pattern are also commented upon. (author)

  6. Transition at the deliquesce point in single salts

    DEFF Research Database (Denmark)

    Rörig-Dalgaard, Inge

    2014-01-01

    Background: Deliquesce points for single salts are in general considered to occur at a specific relative humidity and are also shown as such in phase diagrams. For this reason, salts are used for calibration purpose. According to Gibbs phase rule, the crystalline solid and the saturated solution...... the increasing numbers of thin film water till 20 mbar at 25˚C whereas the deliquescence point is at 24 mbar. These results suggest a stepwise change in the state of the salt. During preparation to salt calibration tests (in a Dynamic Vapour Sorption equipment (DVS)) the author noticed that some single salts...... have a very sudden and accurate change in salt state whereas another salt changed inaccurate as was noticed with NaCl (seen in more than 10 salt preparations). In the present work, the inaccurate transition between the solid NaCl to NaCl in solution was investigated with a cooling stage (CS) in an ESEM...

  7. In situ adsorption of bovine submaxillary mucin at the mica/aqueous solution interface

    International Nuclear Information System (INIS)

    Perez, E.; Proust, J.E.; Baszkin, A.; Boissonnade, M.M.

    1984-01-01

    An in situ adsorption measurement method at the mica/protein solution interface is described. An apparatus especially constructed for this purpose permits direct and continuous measurement of total adsorption (reversible and irreversible) of 14 C-labelled proteins. Bovine submaxillary mucin (BSM), extracted from salivary glands, was acetylated with (CH 3 14 CO) 2 O. The results show the increase of BSM adsorbed on mica surfaces with its concentration in solution and adsorption time. Pseudo plateaux are obtained for all concentrations studied, indicating the formation of thick layers. The loosely bound fraction of adsorbed mucin is proportional to the bulk concentration in solution. The amount of BSM adsorbed increases in the neighbourhood of the isoelectric point of BSM (pH 3). (Auth.)

  8. 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...

  9. Salt Rejection of Non-Ionic Polymeric Membranes

    DEFF Research Database (Denmark)

    Bo, P.; Stannett, V.

    1976-01-01

    A modified solution-diffusion model for the description of salt and water transport through homogeneous membranes is introduced. It is compared with the current solution-diffusion model and the combined flow-diffusion model for the description of transport under reverse osmosis conditions....... The advantage of the modified description over the current solution-diffusion model is the inclusion of a salt-water coupling transport coefficient which allows the description to be extended to membranes of high water permeability (high water content). The advantage of the modified solution-diffusion model...

  10. Chemical equilibrium of hydrogen and aqueous solutions of 1 : 1 bicarbonate and formate salts with a common cation

    NARCIS (Netherlands)

    Engel, D.C.; Versteeg, G.F.; Swaaij, W.P.M. van

    1997-01-01

    The chemical equilibrium of hydrogen and aqueous solutions of 1:1 bicarbonate and formate salts with a common cation has been investigated in an intensively stirred batch reactor: MHCO3(aq) + H2(aq) ↔ MOOCH(aq) + H2O(l) This was accomplished for the sodium (M = Na), potassium (M = K) and ammonium (M

  11. Patterned forests of vertically-aligned multiwalled carbon nanotubes using metal salt catalyst solutions.

    Science.gov (United States)

    Garrett, David J; Flavel, Benjamin S; Baronian, Keith H R; Downard, Alison J

    2013-01-01

    A simple method for producing patterned forests of multiwalled carbon nanotubes (MWCNTs) is described. An aqueous metal salt solution is spin-coated onto a substrate patterned with photoresist by standard methods. The photoresist is removed by acetone washing leaving the acetone-insoluble catalyst pattern on the substrate. Dense forests of vertically aligned (VA) MWCNTs are grown on the patterned catalyst layers by chemical vapour deposition. The procedures have been demonstrated by growing MWCNT forests on two substrates: silicon and conducting graphitic carbon films. The forests adhere strongly to the substrates and when grown directly on carbon film, offer a simple method of preparing MWCNT electrodes.

  12. 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

  13. Proteolysis of truncated hemolysin A yields a stable dimerization interface

    Energy Technology Data Exchange (ETDEWEB)

    Novak, Walter R.P.; Bhattacharyya, Basudeb; Grilley, Daniel P.; Weaver, Todd M. (Wabash); (UW)

    2017-02-21

    Wild-type and variant forms of HpmA265 (truncated hemolysin A) fromProteus mirabilisreveal a right-handed, parallel β-helix capped and flanked by segments of antiparallel β-strands. The low-salt crystal structures form a dimeric structureviathe implementation of on-edge main-chain hydrogen bonds donated by residues 243–263 of adjacent monomers. Surprisingly, in the high-salt structures of two variants, Y134A and Q125A-Y134A, a new dimeric interface is formedviamain-chain hydrogen bonds donated by residues 203–215 of adjacent monomers, and a previously unobserved tetramer is formed. In addition, an eight-stranded antiparallel β-sheet is formed from the flap regions of crystallographically related monomers in the high-salt structures. This new interface is possible owing to additional proteolysis of these variants after Tyr240. The interface formed in the high-salt crystal forms of hemolysin A variants may mimic the on-edge β-strand positioning used in template-assisted hemolytic activity.

  14. Salt splitting with ceramic membranes

    International Nuclear Information System (INIS)

    Kurath, D.

    1996-01-01

    The purpose of this task is to develop ceramic membrane technologies for salt splitting of radioactively contaminated sodium salt solutions. This technology has the potential to reduce the low-level waste (LLW) disposal volume, the pH and sodium hydroxide content for subsequent processing steps, the sodium content of interstitial liquid in high-level waste (HLW) sludges, and provide sodium hydroxide free of aluminum for recycle within processing plants at the DOE complex. Potential deployment sites include Hanford, Savannah River, and Idaho National Engineering Laboratory (INEL). The technical approach consists of electrochemical separation of sodium ions from the salt solution using sodium (Na) Super Ion Conductors (NaSICON). As the name implies, sodium ions are transported rapidly through these ceramic crystals even at room temperatures

  15. The Effect of Salt Splash on Nylon 6,6

    OpenAIRE

    Steward, Scott D

    1999-01-01

    Abstract: One of the most common environmental exposures that nylon undergoes, when used for automotive applications, is that of salt splash, which commonly occurs during winter driving. This study looks at the effect of various salts (NaCl, KCl, CaCl2) on the thermal and mechanical properties of nylon when exposed to one and four molar aqueous salt solutions. It was found that the diffusion of salt solutions into nylon 6,6 occurred in a pseudo-Fickian manner. Also, it was found that the p...

  16. Study of the carbon material / electrolyte interface; Etude de l`interface materiau carbone / electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Genies, S.; Yazami, R. [Ecole Nationale Superieure d`Electrochimie et d`Electrometallurgie, 38 - Saint-Martin-d`Heres (France); Frison, J.C. [CNET, Centre de Recherches de Lannion, 22 (France); Ledran, J. [CNET, 92 - Issy-les-Moulineaux (France)

    1996-12-31

    The aim of this work is the comparative study of the properties of the natural graphite/liquid organic electrolyte interface by impedance spectroscopy with respect to different lithium salts (LiX with X = ClO{sub 4}{sup -}, BF{sub 4}{sup -}, CF{sub 3}SO{sub 3}{sup -}, N(CF{sub 3}SO{sub 2}){sub 2}{sup -}, PF{sub 6}{sup -}). The evolution of the interface properties during the first electrochemical reduction suggests different mechanisms of formation of passivation films. A more stable, thin and homogenous film seems to develop when the LiN(CF{sub 3}SO{sub 2}){sub 2} or LiPF{sub 6} lithium salts are used. The chemical diffusion coefficient of lithium in graphite has been determined by impedance spectroscopy. (J.S.) 16 refs.

  17. Study of the carbon material / electrolyte interface; Etude de l`interface materiau carbone / electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Genies, S; Yazami, R [Ecole Nationale Superieure d` Electrochimie et d` Electrometallurgie, 38 - Saint-Martin-d` Heres (France); Frison, J C [CNET, Centre de Recherches de Lannion, 22 (France); Ledran, J [CNET, 92 - Issy-les-Moulineaux (France)

    1997-12-31

    The aim of this work is the comparative study of the properties of the natural graphite/liquid organic electrolyte interface by impedance spectroscopy with respect to different lithium salts (LiX with X = ClO{sub 4}{sup -}, BF{sub 4}{sup -}, CF{sub 3}SO{sub 3}{sup -}, N(CF{sub 3}SO{sub 2}){sub 2}{sup -}, PF{sub 6}{sup -}). The evolution of the interface properties during the first electrochemical reduction suggests different mechanisms of formation of passivation films. A more stable, thin and homogenous film seems to develop when the LiN(CF{sub 3}SO{sub 2}){sub 2} or LiPF{sub 6} lithium salts are used. The chemical diffusion coefficient of lithium in graphite has been determined by impedance spectroscopy. (J.S.) 16 refs.

  18. Study of the physicochemical properties of the interface between titanium dioxide and various aqueous solutions

    International Nuclear Information System (INIS)

    Mazilier, C.

    1988-01-01

    The aim of this work is the study of ion exchange capacity of titanium dioxide in view of high temperature water purification and radioactive effluent processing because of its resistance to heat and radiations. Titanium dioxide is obtained by alkaline hydrolysis of an aqueous solution of Ti (IV) and is characterized by analytical physical chemistry methods. Interface between Ti0 2 and simple aqueous solutions (electrolytes) is more particularly studied by potentiometry [fr

  19. 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.

  20. Nuclear criticality safety evaluation of the passage of decontaminated salt solution from the ITP filters into tank 50H for interim storage

    International Nuclear Information System (INIS)

    Hobbs, D.T.; Davis, J.R.

    1994-01-01

    This report assesses the nuclear criticality safety associated with the decontaminated salt solution after passing through the In-Tank Precipitation (ITP) filters, through the stripper columns and into Tank 50H for interim storage until transfer to the Saltstone facility. The criticality safety basis for the ITP process is documented. Criticality safety in the ITP filtrate has been analyzed under normal and process upset conditions. This report evaluates the potential for criticality due to the precipitation or crystallization of fissionable material from solution and an ITP process filter failure in which insoluble material carryover from salt dissolution is present. It is concluded that no single inadvertent error will cause criticality and that the process will remain subcritical under normal and credible abnormal conditions

  1. Measurement of resistance to solute transport across surfactant-laden interfaces using a Fluorescence Recovery After Photobleaching (FRAP) technique

    Science.gov (United States)

    Browne, Edward P.; Nivaggioli, Thierry; Hatton, T. Alan

    1994-01-01

    A noninvasive fluorescence recovery after photobleaching (FRAP) technique is under development to measure interfacial transport in two phase systems without disturbing the interface. The concentration profiles of a probe solute are measured in both sides of the interface by argon-ion laser, and the system relaxation is then monitored by a microscope-mounted CCD camera.

  2. Second harmonic generation study of malachite green adsorption at the interface between air and an electrolyte solution: observing the effect of excess electrical charge density at the interface.

    Science.gov (United States)

    Song, Jinsuk; Kim, Mahn Won

    2010-03-11

    Understanding the differential adsorption of ions at the interface of an electrolyte solution is very important because it is closely related, not only to the fundamental aspects of biological systems, but also to many industrial applications. We have measured the excess interfacial negative charge density at air-electrolyte solution interfaces by using resonant second harmonic generation of oppositely charged probe molecules. The excess charge density increased with the square root of the bulk electrolyte concentration. A new adsorption model that includes the electrostatic interaction between adsorbed molecules is proposed to explain the measured adsorption isotherm, and it is in good agreement with the experimental results.

  3. Influence of electro-activated solutions of weak organic acid salts on microbial quality and overall appearance of blueberries during storage.

    Science.gov (United States)

    Liato, Viacheslav; Hammami, Riadh; Aïder, Mohammed

    2017-06-01

    The aim of this work was to study the potential of diluted electro-activated solutions of weak organic acid salts (potassium acetate, potassium citrate and calcium lactate) to extend the shelf life of blueberries during post-harvest storage. The sanitizing capacity of these solutions was studied against pathogenic bacteria Listeria monocytogenes and E. coli O157:H7 as well as phytopathogenic fungi A. alternata, F. oxysporum and B. cinerea. The results showed that a 5-min treatment of inoculated blueberries with electro-activated solutions resulted in a 4 log CFU/g reduction in Listeria monocytogenes for all solutions. For E. coli O157:H7, the electro-activated potassium acetate and potassium citrate solutions achieved a decrease of 3.5 log CFU/g after 5 min of berry washing. The most important fungus reduction was found when blueberries were washed with an electro-activated solution of potassium acetate and a NaOCl solution. After 5 min of blueberry washing with an electro-activated potassium acetate solution, a very high reduction effect was observed for A. alternata, F. oxysporum and B. cinerea, which showed survival levels of only 2.2 ± 0.16, 0.34 ± 0.15 and 0.21 ± 0.16 log CFU/g, respectively. Regarding the effect of the washing on the organoleptic quality of blueberries, the obtained results showed no negative effect on the product color or textural profile. Finally, this work suggests that washing with electro-activated solutions of weak organic acid salts can be used to enhance the shelf-life of blueberries during post-harvest storage. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. 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.

  5. 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.

  6. pH-potentiometric determination of solubility of barely soluble organic extracting agents in water and aqueous solutions of neutral salts

    International Nuclear Information System (INIS)

    Pavlovskaya, E.M.; Charykov, A.K.; Tikhomirov, V.I.

    1977-01-01

    A pH-potentiometric method has been used to estimate the solubility of chloroform, benzene and nitrobenzene in water. The desalting effect is studied of alkali metal chlorides on chloroform solubility to establish the following phenomenological series of alkali metal cations by their desalting action: Li + + + + + . The non-conformity of chloroform solubility values in water-isoactive solutions of different salts is indicative of the high specificity of desalting processes with respect to the chemical nature of the desalting cation. Salt effects also essentially depend on the chemical nature of the desalted substance, particularly on its acid-base properties

  7. Numerical modelling of two-layer shallow water flow in microtidal salt-wedge estuaries: Finite volume solver and field validation

    Directory of Open Access Journals (Sweden)

    Krvavica Nino

    2017-03-01

    Full Text Available A finite volume model for two-layer shallow water flow in microtidal salt-wedge estuaries is presented in this work. The governing equations are a coupled system of shallow water equations with source terms accounting for irregular channel geometry and shear stress at the bed and interface between the layers. To solve this system we applied the Q-scheme of Roe with suitable treatment of source terms, coupling terms, and wet-dry fronts. The proposed numerical model is explicit in time, shock-capturing and it satisfies the extended conservation property for water at rest. The model was validated by comparing the steady-state solutions against a known arrested salt-wedge model and by comparing both steady-state and time-dependant solutions against field observations in Rječina Estuary in Croatia. When the interfacial friction factor λi was chosen correctly, the agreement between numerical results and field observations was satisfactory.

  8. Electrochemical-metallothermic reduction of zirconium in molten salt solutions

    International Nuclear Information System (INIS)

    McLaughlin, D.F.; Talko, F.

    1990-01-01

    This patent describes a method for separating hafnium from zirconium of the type wherein a feed containing zirconium and hafnium chlorides is prepared from zirconium-hafnium chloride and the feed is introduced into a distillation column, which distillation column has a reboiler connected at the bottom and a reflux condenser connected at the top and wherein a hafnium chloride enriched stream is taken from the top of the column and a zirconium enriched chloride stream is taken from the bottom of the column. It comprises: reducing the zirconium enriched chloride stream taken from the distillation column to metal by electrochemically reducing an alkaline earth metal in a molten salt bath with the molten salt in the molten salt bath consisting essentially of a mixture of at least one alkali metal chloride and at least one alkaline earth metal chloride and zirconium chloride, with the reduced alkaline earth metal reacting with the zirconium chloride to produce zirconium metal and alkaline earth metal chloride

  9. Synthesis of nanometer metallic powders or its oxides by γ-ray reduction of salts aqueous solution

    International Nuclear Information System (INIS)

    Zhang Manwei; Zhu Yingjie; Qian Yitai; Chen Zuyao

    1995-01-01

    The nanocrystal powders of pure Ag, Cu, Ni, Pt, Au, Pd, Cd, Sn, Pb and Co were obtained by γ-radiation reduction of their salt aqueons solution. The average particle sizes of them are 5-45 nm respectively. the factors affecting the particle size and the formation and growth of the nanocrystal particles into single crystal are illustrated and discussed. the pure nanocrystal Cu 2 O powders were also successfully prepared. The mechanism of its formation is discussed. (author)

  10. Molecular dynamics simulations of hydrophobous ions at the liquid-liquid interfaces: case of dicarbollide anions as synergy agents and of ionic liquids as extracting medium

    International Nuclear Information System (INIS)

    Chevrot, G.

    2008-01-01

    Based on molecular dynamics simulations, we first describe the distribution of dicarbollide salts (CCD - , Mn + ) in concentrated monophasic solutions (water, chloroform, octanol, nitrobenzene) and in the corresponding biphasic 'oil' - water solutions. We point to the importance of surface activity of the CCD - s and of their self-aggregation in water, with marked counterions effects, and we explain the synergistic effect of CCD - s in the Eu 3+ extraction by BTP ligands. In the second part of the thesis we report exploratory simulations on the extraction of Sr 2+ by 18-crown-6 to an hydrophobic ionic liquid ([BMI][PF6]), focusing on the liquid - liquid interface. Analogies and differences with a classical aqueous interface are outlined. (author)

  11. Analytical Solution of Interface Effect on the Strength of Combined Model Composed of Different Geologic Bodies

    Directory of Open Access Journals (Sweden)

    Zeng-hui Zhao

    2014-01-01

    Full Text Available According to the special combined structure of surrounding rock in western mining area of China, a micromechanical model with variable parameters containing contact interface was proposed firstly. Then, the derived stresses in coal and rock near the interface were analyzed on the basis of the harmonized strain relation, and the analytical solutions with respect to stress states near the interface were drawn up. The triaxial compressive strength of coal and rock was further determined in case the contact interface was in the horizontal position. Moreover, effects of stiffness ratio, interface angle, and stress level on the strength of two bodies near the contact area were expounded in detail. Results indicate that additional stresses which have significant effect on the strength of combined model are derived due to the adhesive effect of contact interface and lithological differences between geologic bodies located on both sides. The interface effect on the strength of combined body is most associated with the stiffness, interface angle, and the stress level. These conclusions are also basically valid for three-body model and even for the multibody model and lay important theory foundation to guide the stability study of soft strata composed of different geologic bodies.

  12. Adsorption of benzyldimethylhexadecylammonium chloride at the hydrophobic silica-water interface studied by total internal reflection Raman spectroscopy: effects of silica surface properties and metal salt addition.

    Science.gov (United States)

    Grenoble, Zlata; Baldelli, Steven

    2013-08-29

    The adsorption of the cationic surfactant benzyldimethylhexadecylammonium (BDMHA(+)) chloride was studied at an octadecyltrichlorosilane (OTS)-monolayer-modified silica-water interface by Raman spectroscopy in total internal reflection (TIR) geometry. The present study demonstrates the capabilities of this spectroscopic technique to evaluate thermodynamic and kinetic BDMHA(+)Cl(-) adsorption properties at the hydrophobic silica surface. The surface coverage of BDMHA(+) decreased by 50% at the hydrophobic OTS-silica surface relative to the surface coverage on bare silica; the dominating driving mechanisms for surfactant adsorption were identified as hydrophobic effects and head group charge screening by the electrolyte counterions. Addition of magnesium metal salt (MgCl2) to the aqueous solution (∼ neutral pH) lowered the surface coverage and moderately increased the Langmuir adsorption constants relative to those of the pure surfactant. These trends were previously observed at the hydrophilic, negatively charged silica surface but with a smaller change in the Gibbs free energy of adsorption at the hydrophobic silica surface. The hydrophobic OTS-silica surface properties resulted in shorter times for the surfactant to reach steady-state adsorption conditions compared to the slow adsorption kinetics previously seen with the surfactant at the hydrophilic surface. Adsorption isotherms, based on Raman signal intensities from spectral analysis, were developed according to the Langmuir adsorption model for the pure surfactant at the OTS-silica-water interface; the modified Langmuir model was applied to the surfactant adsorption in the presence of 5, 10, 50, and 100 mM magnesium chloride. Spectral analysis of the Raman scattering intensities and geometric considerations suggests a hemimicelle-type surface aggregate as the most likely surfactant structure at the OTS-silica surface. The different kinetics observed at the hydrophilic versus the hydrophobic silica surface

  13. Mechano-Chemical Interactions at Cement-Geomaterial Interfaces in Repository and Borehole Scenarios

    Science.gov (United States)

    Mohagheghi, J. R.; Dewers, T. A.; Matteo, E. N.; Heath, J. E.; Jove Colon, C. F.; Fuller, T.

    2017-12-01

    A number of factors negatively affect wellbore integrity including interactions at boundaries between cement and surrounding geomaterial. These include mechanical and chemical mechanisms that can lead to wellbore failure. To examine these interactions, potential coupling, and pathways to failure, we discuss progress on an experimental and modeling study involving cement-clay and cement-salt interfaces. A sample shotcrete-bentonite interface from the FEBEX heater test at the Grimsel Test Site in Switzerland is examined using multi-beam scanning electron microscopy (mSEM) at 4 nm resolution over an area 10's of square millimeters. We examine changes in alteration as manifested by pore structural changes as a function of distance from the interface. A parallel effort examines time-dependent changes in interface structure in cement cores in a triaxial coreholder. Cores are exposed to conditions of 70oC, 14 MPa pressure, and small differential loads, with degradation being monitored by effluent pH, pulse-echo ultrasonics, and piston displacement (measuring sample shortening). We will measure the mechanical consequences of interface alteration using nano-indentation. Experimental results are being incorporated as a validation effort in a coupled reactive-transport mechanics model linking the Sandia ALBANY finite element code, the KAYENTA elasto-plastic constitutive model, with the reactive transport code PFLOTRAN. Plans call to apply the model to understanding the evolution of the FEBEX sample, as well as a cement-salt sample from the Waste Isolation Pilot Plant in Carlsbad, New Mexico. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc. for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-NA0003525. SAND 2017-8277 A

  14. 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.

  15. 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

  16. Microcomputer interfacing and applications

    CERN Document Server

    Mustafa, M A

    1990-01-01

    This is the applications guide to interfacing microcomputers. It offers practical non-mathematical solutions to interfacing problems in many applications including data acquisition and control. Emphasis is given to the definition of the objectives of the interface, then comparing possible solutions and producing the best interface for every situation. Dr Mustafa A Mustafa is a senior designer of control equipment and has written many technical articles and papers on the subject of computers and their application to control engineering.

  17. Solution of the mathematical adjoint equations for an interface current nodal formulation

    International Nuclear Information System (INIS)

    Yang, W.S.; Taiwo, T.A.; Khalil, H.

    1994-01-01

    Two techniques for solving the mathematical adjoint equations of an interface current nodal method are described. These techniques are the ''similarity transformation'' procedure and a direct solution scheme. A theoretical basis is provided for the similarity transformation procedure originally proposed by Lawrence. It is shown that the matrices associated with the mathematical and physical adjoint equations are similar to each other for the flat transverse leakage approximation but not for the quadratic leakage approximation. It is also shown that a good approximate solution of the mathematical adjoint for the quadratic transverse leakage approximation is obtained by applying the similarity transformation for the flat transverse leakage approximation to the physical adjoint solution. The direct solution scheme, which was developed as an alternative to the similarity transformation procedure, yields the correct mathematical adjoint solution for both flat and quadratic transverse leakage approximations. In this scheme, adjoint nodal equations are cast in a form very similar to that of the forward equations by employing a linear transformation of the adjoint partial currents. This enables the use of the forward solution algorithm with only minor modifications for solving the mathematical adjoint equations. By using the direct solution scheme as a reference method, it is shown that while the results computed with the similarity transformation procedure are approximate, they are sufficiently accurate for calculations of global and local reactivity changes resulting from coolant voiding in a liquid-metal reactor

  18. Electrochemical Study of Modified Glassy Carbon Electrode with Carboxyphenyl Diazonium Salt in Aqueous Solutions

    Directory of Open Access Journals (Sweden)

    Mariem BOUROUROU

    2014-05-01

    Full Text Available The covalent grafting of carboxyphenyl functionalities to planar carbon substrates by reaction with 2-carboxybenezenediazonium salt has been studied in aqueous acid solution. The surface was characterized, before and after the functionnalization process, by cyclic voltammetry, electrochemical impedance spectroscopy and linear sweep voltammetry (LSV in order to control and to prove the formation of a coating on the carbon surface. The results indicate the presence of substituted phenyl groups on the investigated surface. Electrochemical impedance measurements show that the slowing down of the electron transfer kinetics was more evident by increasing the number of cycles resulting to higher DEp and RCT parameters. Besides, the effect of the pH on the electron transfer processes of the Fe(CN63-/4- at the modified electrode is studied. By changing the solution pH the terminal group’s charge state would vary, based on which the surface pKa value is estimated.

  19. Potentiometric titration of uranium reduced by chromic salts in chloridic solutions; Titulacao potenciometrica de uranio reduzido por sais cromosos em solucoes cloridricas

    Energy Technology Data Exchange (ETDEWEB)

    Coutinho, C M.C.; Bastos, E T.R.

    1986-06-01

    The utilization of chromic salts for reducing the uranium (VI) from chloridic solutions, for potentiometric dosage is described. This method is used in the range of 0,002 to 1,0 M of uranium. (C.G.C.).

  20. Customer interface document for the Molten Salt Test Loop (MSTL) system.

    Energy Technology Data Exchange (ETDEWEB)

    Pettit, Kathleen; Kolb, William J.; Gill, David Dennis; Briggs, Ronald D.

    2012-03-01

    The National Solar Thermal Test Facility at Sandia National Laboratories has a unique test capability called the Molten Salt Test Loop (MSTL) system. MSTL is a test capability that allows customers and researchers to test components in flowing, molten nitrate salt. The components tested can range from materials samples, to individual components such as flex hoses, ball joints, and valves, up to full solar collecting systems such as central receiver panels, parabolic troughs, or linear Fresnel systems. MSTL provides realistic conditions similar to a portion of a concentrating solar power facility. The facility currently uses 60/40 nitrate 'solar salt' and can circulate the salt at pressure up to 600psi, temperature to 585 C, and flow rate of 400-600GPM depending on temperature. The purpose of this document is to provide a basis for customers to evaluate the applicability to their testing needs, and to provide an outline of expectations for conducting testing on MSTL. The document can serve as the basis for testing agreements including Work for Others (WFO) and Cooperative Research and Development Agreements (CRADA). While this document provides the basis for these agreements and describes some of the requirements for testing using MSTL and on the site at Sandia, the document is not sufficient by itself as a test agreement. The document, however, does provide customers with a uniform set of information to begin the test planning process.

  1. Contribution to the study of uranyl salts in butyl phosphate solutions; Contribution a l'etude des solutions de sels d'uranyle dans les phosphates butyliques

    Energy Technology Data Exchange (ETDEWEB)

    Coulon, A [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    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 {approx} 1270 cm{sup -1} to {approx} 1180 cm{sup -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) [French] Une etude spectroscopique dans l'infrarouge moyen portant sur les associations: - phosphates trialcoyliques (tributylique - triethylique - trimethylique) - sels d'uranyle (nitrate, chlorure, acetate) a confirme l'existence d'une interaction entre le groupement phosphoryle et l'atome d'uranium, se manifestant par un deplacement de la bande d'absorption de la vibration de valence P = 0 de {approx} 1270 cm{sup -1} a {approx} 1180 cm{sup -1}. Une etude preparative, analytique et spectroscopique des solides obtenus par precipitation de sels d'uranyle par les phosphates butyliques acides a ete effectuee. La spectrophotomerie infrarouge met en evidence l'association, anterieure a toute introduction d'uranium, des phosphates tributylique et dibutylique dans des diluants non polaires. L'extraction de sels d'uranyle, d'une solution aqueuse acide par un melange dilue de phosphates tributylique et dibutylique, s'effectue suivant des processus differents a la nature de l'anion (nitrate ou chlorure). (auteur)

  2. Salt bridges: geometrically specific, designable interactions.

    Science.gov (United States)

    Donald, Jason E; Kulp, Daniel W; DeGrado, William F

    2011-03-01

    Salt bridges occur frequently in proteins, providing conformational specificity and contributing to molecular recognition and catalysis. We present a comprehensive analysis of these interactions in protein structures by surveying a large database of protein structures. Salt bridges between Asp or Glu and His, Arg, or Lys display extremely well-defined geometric preferences. Several previously observed preferences are confirmed, and others that were previously unrecognized are discovered. Salt bridges are explored for their preferences for different separations in sequence and in space, geometric preferences within proteins and at protein-protein interfaces, co-operativity in networked salt bridges, inclusion within metal-binding sites, preference for acidic electrons, apparent conformational side chain entropy reduction on formation, and degree of burial. Salt bridges occur far more frequently between residues at close than distant sequence separations, but, at close distances, there remain strong preferences for salt bridges at specific separations. Specific types of complex salt bridges, involving three or more members, are also discovered. As we observe a strong relationship between the propensity to form a salt bridge and the placement of salt-bridging residues in protein sequences, we discuss the role that salt bridges might play in kinetically influencing protein folding and thermodynamically stabilizing the native conformation. We also develop a quantitative method to select appropriate crystal structure resolution and B-factor cutoffs. Detailed knowledge of these geometric and sequence dependences should aid de novo design and prediction algorithms. Copyright © 2010 Wiley-Liss, Inc.

  3. Study of the interactions between alumina and metallic ion in solution at the liquid/oxide interface during catalysts synthesis; Etude des interactions alumine/ion metallique en solution a l`interface oxyde/liquide lors de la preparation des catalyseurs

    Energy Technology Data Exchange (ETDEWEB)

    Mertens de Wilmars, D.

    1998-01-15

    This work concerns the formation of compounds including metal and Al(III) ions during impregnation of gamma alumina with a solution of the metal precursor. Formation of Li/Al hydroxy-carbonate (Li/Al HDC) on alumina during impregnation by a neutral or basic solution containing Li{sup +} is established. Zeta potential measurements are used to determine the ratio overlay of the alumina by HDC Li/Al. By this technique, residual positive charges are observed on HDC Li/Al surface. The formation of two different compounds including Mo(VI) and Al(III) ions during impregnation of alumina with molybdate or hepta-molybdate solution is reported here for the first time. The use of sodium molybdate solution as impregnation precursor leads to the formation of hydroxy-molybdo-luminate, while the ammonium hepta-molybdate solution forms ammonium hexa-molybdo-aluminate by contact with alumina.Dissolution kinetics of alumina in aqueous solution in absence or in presence of metal ions (Li{sup +}, K{sup +}, Zn{sup 2+}, MoO{sub 4}{sup 2-}, Mo{sub 7}O{sub 24}{sup 6-}) are investigated at different pH. Results show that the support is not inert in aqueous solution, even at neutral pH (near ZPC). The homogeneous nucleation of Li/Al HDC observed for Li/Al{sub 2}O{sub 3} system evidence the permeability of the solid/solution interface: diffusion processus through the interface is more important than previously reported. A dissolution-precipitation mechanism is proposed to account for the formation of Al(III)-containing compounds on alumina surface. Alumina dissolves when contacted with aqueous solution. When Al(III) ions concentration in solution is bigger than the sur-saturation needed for heterogenous nucleation of the Al(III) containing compounds, this one precipitates. This mechanism agrees with all our results. (author) 169 refs.

  4. Kinetics of Surfactant Desorption at an Air–Solution Interface

    KAUST Repository

    Morgan, C. E.

    2012-12-18

    The kinetics of re-equilibration of the anionic surfactant sodium dodecylbenzene sulfonate at the air-solution interface have been studied using neutron reflectivity. The experimental arrangement incorporates a novel flow cell in which the subphase can be exchanged (diluted) using a laminar flow while the surface region remains unaltered. The rate of the re-equilibration is relatively slow and occurs over many tens of minutes, which is comparable with the dilution time scale of approximately 10-30 min. A detailed mathematical model, in which the rate of the desorption is determined by transport through a near-surface diffusion layer into a diluted bulk solution below, is developed and provides a good description of the time-dependent adsorption data. A key parameter of the model is the ratio of the depth of the diffusion layer, H c, to the depth of the fluid, Hf, and we find that this is related to the reduced Péclet number, Pe*, for the system, via Hc/Hf = C/Pe*1/2. Although from a highly idealized experimental arrangement, the results provide an important insight into the "rinse mechanism", which is applicable to a wide variety of domestic and industrial circumstances. © 2012 American Chemical Society.

  5. Molecular dynamics simulations of hydrophobous ions at the liquid-liquid interfaces: case of dicarbollide anions as synergy agents and of ionic liquids as extracting medium; Simulations par dynamique moleculaire d'ions hydrophobes aux interfaces liquide - liquide: le cas des anions dicarbollides comme agents de synergie et celui des liquides ioniques comme milieu extractant

    Energy Technology Data Exchange (ETDEWEB)

    Chevrot, G

    2008-01-15

    Based on molecular dynamics simulations, we first describe the distribution of dicarbollide salts (CCD{sup -}, Mn{sup +}) in concentrated monophasic solutions (water, chloroform, octanol, nitrobenzene) and in the corresponding biphasic 'oil' - water solutions. We point to the importance of surface activity of the CCD{sup -}s and of their self-aggregation in water, with marked counterions effects, and we explain the synergistic effect of CCD{sup -}s in the Eu{sup 3+} extraction by BTP ligands. In the second part of the thesis we report exploratory simulations on the extraction of Sr{sup 2+} by 18-crown-6 to an hydrophobic ionic liquid ([BMI][PF6]), focusing on the liquid - liquid interface. Analogies and differences with a classical aqueous interface are outlined. (author)

  6. 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

  7. Photobleachable Diazonium Salt-Phenolic Resin Two-Layer Resist System

    Science.gov (United States)

    Uchino, Shou-ichi; Iwayanagi, Takao; Hashimoto, Michiaki

    1988-01-01

    This article describes a new negative two-layer photoresist system formed by a simple, successive spin-coating method. An aqueous acetic acid solution of diazonium salt and poly(N-vinylpyrrolidone) is deposited so as to contact a phenolic resin film spin-coated on a silicon wafer. The diazonium salt diffuses into the phenolic resin layer after standing for several minutes. The residual solution on the phenolic resin film doped with diazonium salt is spun to form the diazonium salt-poly(N-vinylpyrrolidone) top layer. This forms a uniform two-layer resist without phase separation or striation. Upon UV exposure, the diazonium salt in the top layer bleaches to act as a CEL dye, while the diazonium salt in the bottom layer decomposes to cause insolubilization. Half μm line-and-space patterns are obtained with an i-line stepper using 4-diazo-N,N-dimethylaniline chloride zinc chloride double salt as the diazonium salt and a cresol novolac resin for the bottom polymer layer. The resist formation processes, insolubilization mechanism, and the resolution capability of the new two-layer resist are discussed.

  8. Many-electron electrochemical processes. Reactions in molten salts, room-temperature ionic liquids and ionic solutions

    Energy Technology Data Exchange (ETDEWEB)

    Andriiko, Aleksandr A. [National Technical Univ. Ukraine, Kyiv (Ukraine). Kyiv Polytechnic Inst.; Andriyko, Yuriy O. [CEST Centre of Electrochemical Surface Technology, Wiener Neustadt (Austria); Nauer, Gerhard E. [Vienna Univ. (Austria). Inst. of Physical Chemistry

    2013-02-01

    The authors provide a unified concept for understanding multi-electron processes in electrochemical systems such as molten salts, ionic liquids, or ionic solutions. A major advantage of this concept is its independence of assumptions like one-step many-electron transfers or 'discrete' discharge of complex species. This book contains the following main topics: 1. Many-electron electrochemical systems: Concepts and definitions. 2. Many-electron systems at equilibrium. 3. Phenomenology of electrochemical kinetics. 4. Electrode film systems: experimental evidences. 5. Dynamics of a non-equilibrium electrochemical system. 6. Electrochemistry of Ti(IV) in ionic liquids.

  9. INORGANIC AND ORGANIC ONIUM SALTS

    Science.gov (United States)

    The nitrosonium NO ion absorbs in the infrared between 1/2400 and 1/ 2150 cm. Salts of complex fluoro-acids absorb at higher frequencies than salts...halide adducts generally contain nitrosonium ions . Hexaphenylditin does not undergo marked heterolytic dissociation in nitromethane solution...influencing the covalent-ionic equilibrium are discussed. Infrared spectrum nitrosonium ion ; ionic character in lattice and position nitrosonium ion absorption

  10. Fractal-like thickness and topography of the salt layer in a pillows province of the southern North Sea

    Science.gov (United States)

    Hernandez Maya, K.; Mitchell, N. C.; Huuse, M.

    2017-12-01

    Salt topography and thickness variations are important for testing theories of how halokinetic deformation proceeds. The ability to predict thickness variations of salt at small scale is also important for reservoir evaluations, as breach of the salt layer can lead to loss of petroleum fluids and can be difficult to evaluate from seismic reflection data. Relevant to these issues, we here report analysis of data on salt layer topography and thickness from the southern North Sea, where the salt is organized into pillows. These data were derived by the Geological Survey of the Netherlands (TNO) from industry 3D seismic reflection data combined with a dense network of well information. Highs and lows in the topography of the upper salt interface occur spaced over a variety of lengthscales. Power spectral analysis of the interface topography reveals a simple inverse power law relationship between power spectral density and spatial wave number. The relationship suggests that the interface is a self-affine fractal with a fractal dimension of 2.85. A similar analysis of the salt layer thickness also suggests a fractal-like power law. Whereas the layer thickness power law is unsurprising as the underlying basement topography dominates the thickness and it also has a fractal-like power spectrum, the salt topography is not so easily explained as not all the basement faults are overlaid by salt pillows, instead some areas of the dataset salt thinning overlies faults. We consider instead whether a spatially varied loading of the salt layer may have caused this fractal-like geometry. Varied density and thickness of overburdening layers seem unlikely causes, as thicknesses of layers and their reflectivities do not vary sympathetically with the topography of the interface. The composition of the salt layer varies with the relative proportions of halite and denser anhydrite and other minerals. Although limited in scope and representing the mobilized salt layer, the information from

  11. Plutonium and americium separation from salts

    International Nuclear Information System (INIS)

    Hagan, P.G.; Miner, F.J.

    1976-01-01

    Salts or materials containing plutonium and americium are dissolved in hydrochloric acid, heated, and contacted with an alkali metal carbonate solution to precipitate plutonium and americium carbonates which are thereafter readily separable from the solution

  12. Nonspecific DNA Binding and Bending by HUαβ: Interfaces of the Three Binding Modes Characterized by Salt Dependent Thermodynamics

    Science.gov (United States)

    Koh, Junseock; Shkel, Irina; Saecker, Ruth M.; Record, M. Thomas

    2011-01-01

    Previous ITC and FRET studies demonstrated that Escherichia coli HUαβ binds nonspecifically to duplex DNA in three different binding modes: a tighter-binding 34 bp mode which interacts with DNA in large (>34 bp) gaps between bound proteins, reversibly bending it 140° and thereby increasing its flexibility, and two weaker, modestly cooperative small-site-size modes (10 bp, 6 bp) useful for filling gaps between bound proteins shorter than 34 bp. Here we use ITC to determine the thermodynamics of these binding modes as a function of salt concentration, and deduce that DNA in the 34 bp mode is bent around but not wrapped on the body of HU, in contrast to specific binding of IHF. Analyses of binding isotherms (8, 15, 34 bp DNA) and initial binding heats (34, 38, 160 bp DNA) reveal that all three modes have similar log-log salt concentration derivatives of the binding constants (Ski) even though their binding site sizes differ greatly; most probable values of Ski on 34 bp or larger DNA are − 7.5 ± 0.5. From the similarity of Ski values, we conclude that binding interfaces of all three modes involve the same region of the arms and saddle of HU. All modes are entropy-driven, as expected for nonspecific binding driven by the polyelectrolyte effect. The bent-DNA 34 bp mode is most endothermic, presumably because of the cost of HU-induced DNA bending, while the 6 bp mode is modestly exothermic at all salt concentrations examined. Structural models consistent with the observed Ski values are proposed. PMID:21513716

  13. Water at Interfaces

    DEFF Research Database (Denmark)

    Björneholm, Olle; Hansen, Martin Hangaard; Hodgson, Andrew

    2016-01-01

    The interfaces of neat water and aqueous solutions play a prominent role in many technological processes and in the environment. Examples of aqueous interfaces are ultrathin water films that cover most hydrophilic surfaces under ambient relative humidities, the liquid/solid interface which drives...

  14. Numerical estimation of structural integrity of salt cavern wells.

    NARCIS (Netherlands)

    Orlic, B.; Thienen-Visser, K. van; Schreppers, G.J.

    2016-01-01

    Finite element analyses were performed to estimate axial deformation of cavern wells due to gas storage operations in solution-mined salt caverns. Caverns shrink over time due to salt creep and the cavern roof subsides potentially threatening well integrity. Cavern deformation, deformation of salt

  15. Dynamic tritium inventory of a NET/ITER fuel cycle with lithium salt solution blanket

    International Nuclear Information System (INIS)

    Spannagel, G.; Gierszewski, P.

    1991-01-01

    At the Karlsruhe Nuclear Research Center (KfK) a flexible tool is being developed to simulate the dynamics of tritium inventories. This tool can be applied to any tritium handling system, especially to the fuel cycle components of future nuclear fusion devices. This instrument of simulation will be validated in equipment to be operated at the Karlsruhe Tritium Laboratory. In this study tritium inventories in a NET/ITER type fuel cycle involving a lithium salt solution blanket are investigated. The salt solution blanket serves as an example because it offers technological properties which are attractive in modeling the process; the example does not impair the general validity of the tool. Usually, the operation strategy of complex structures will deteriorate due to failures of the subsystems involved. These failures together with the reduced availability ensuing from them will be simulated. The example of this study is restricted to reduced availabilities of two subsystems, namely the reactor and the tritium recovery system. For these subsystems the influence of statistically varying intervals of operation is considered. Strategies we selected which are representative of expected modes of operation. In the design of a fuel cycle, care will be taken that prescribed availabilities of the subsystems can be achieved; however, the description of reactor operation is a complex task since operation breaks down into several campaigns for which rules have been specified which enable determination of whether a campaign has been successful and can be stopped. Thus, it is difficult to predict the overall behavior prior to a simulation which includes stochastic elements. Using the example mentioned above the capabilities of the tool will be illustrated; besides the presentation of results of inventory simulation, the applicability of these data will be discussed. (orig.)

  16. Quantitative Studies on PDMS-PDMS Interface Bonding with Piranha Solution and its Swelling Effect

    Directory of Open Access Journals (Sweden)

    Choon-Lai Chiang

    2012-05-01

    Full Text Available In this paper, a low-cost yet effective method of irreversible bonding between two elastomeric polydimethylsiloxane (PDMS interfaces using Piranha solution is investigated. Piranha solutions at a weight ratio of 3:1 using different acids and hydrogen peroxide were attempted. The average tensile strengths of the device bonded with concentrated sulfuric acid-based piranha solution and nitric acid-based piranha solution were found to be 200 ± 20 kPa and 100 ± 15 kPa respectively. A PDMS surface treated with Piranha Solution demonstrated an increase in hydrophilicity. In addition, relatively straightforward swelling studies of PDMS using a weight loss method with common organic solvents were also investigated. Experimental results show that hexane, toluene, ethyl acetate, n-propyl alcohol and acetone swell PDMS significantly over a duration of up to 1 h and above; PDMS samples reached a steady state of swelling only after 5 min of immersion in other solvents. This will enable researchers to develop devices for the future according to the interaction between the material and the solvents in contact.

  17. Cesium Salts of Phosphotungstic Acid: Comparison of Surface ...

    African Journals Online (AJOL)

    NICO

    acidity and lowest solubility in reaction media in comparison with the other cesium content salts. KEYWORDS. Polyoxometalates, cesium ... insoluble salt of HPA is cesium salt of tungstophosphoric acid,. CsxH3-xPW12O40 (CsxPW), a ... of Cs2CO3, very fine particles (precipitates) were formed to make the solution milky.

  18. 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.

  19. Results for the Fourth Quarter Calendar Year 2015 Tank 50H Salt Solution Sample

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-01-11

    In this memorandum, the chemical and radionuclide contaminant results from the Fourth Quarter Calendar Year 2015 (CY15) sample of Tank 50H salt solution are presented in tabulated form. The Fourth Quarter CY15 Tank 50H samples were obtained on October 29, 2015 and received at Savannah River National Laboratory (SRNL) on October 30, 2015. The information from this characterization will be used by Defense Waste Processing Facility (DWPF) & Saltstone Facility Engineering for the transfer of aqueous waste from Tank 50H to the Salt Feed Tank in the Saltstone Production Facility, where the waste will be treated and disposed of in the Saltstone Disposal Facility. This memorandum compares results, where applicable, to Saltstone Waste Acceptance Criteria (WAC) limits and targets. Data pertaining to the regulatory limits for Resource Conservation and Recovery Act (RCRA) metals will be documented at a later time per the Task Technical and Quality Assurance Plan (TTQAP) for the Tank 50H saltstone task. The chemical and radionuclide contaminant results from the characterization of the Fourth Quarter Calendar Year 2015 (CY15) sampling of Tank 50H were requested by SRR personnel and details of the testing are presented in the SRNL Task Technical and Quality Assurance Plan.

  20. The crystallization of a solid solution in a solvent and the stability of a growth interface

    International Nuclear Information System (INIS)

    Malmejac, Yves

    1971-03-01

    The potential uses of germanium-silicon alloys as thermoelectric generators in hitherto unexploited temperature ranges initiated the present study. Many delicate problems are encountered in the classical methods of preparation. An original technique was sought for crystallization in a metallic solvent. The thermodynamic equilibria between the various phases of the ternary System used were studied in order to justify the method used. The conditions (temperature and composition) were determined in which the cooling of a ternary liquid mixture induces the precipitation of a binary solid solution with the desired composition. If large crystals are to be obtained from the solid solution, metallic solvent precipitation must be replaced by a mono-directional solvent crystallization. The combined effect of a certain number of simple physical phenomena on the stability of a crystal liquid interface was studied: the morphological stability of the crystal growth interface is the first step towards obtaining perfect crystals. (author) [fr

  1. Salt-bridge networks within globular and disordered proteins: characterizing trends for designable interactions.

    Science.gov (United States)

    Basu, Sankar; Mukharjee, Debasish

    2017-07-01

    There has been considerable debate about the contribution of salt bridges to the stabilization of protein folds, in spite of their participation in crucial protein functions. Salt bridges appear to contribute to the activity-stability trade-off within proteins by bringing high-entropy charged amino acids into close contacts during the course of their functions. The current study analyzes the modes of association of salt bridges (in terms of networks) within globular proteins and at protein-protein interfaces. While the most common and trivial type of salt bridge is the isolated salt bridge, bifurcated salt bridge appears to be a distinct salt-bridge motif having a special topology and geometry. Bifurcated salt bridges are found ubiquitously in proteins and interprotein complexes. Interesting and attractive examples presenting different modes of interaction are highlighted. Bifurcated salt bridges appear to function as molecular clips that are used to stitch together large surface contours at interacting protein interfaces. The present work also emphasizes the key role of salt-bridge-mediated interactions in the partial folding of proteins containing long stretches of disordered regions. Salt-bridge-mediated interactions seem to be pivotal to the promotion of "disorder-to-order" transitions in small disordered protein fragments and their stabilization upon binding. The results obtained in this work should help to guide efforts to elucidate the modus operandi of these partially disordered proteins, and to conceptualize how these proteins manage to maintain the required amount of disorder even in their bound forms. This work could also potentially facilitate explorations of geometrically specific designable salt bridges through the characterization of composite salt-bridge networks. Graphical abstract ᅟ.

  2. On weak solutions to a diffuse interface model of a binary mixture of compressible fluids

    Czech Academy of Sciences Publication Activity Database

    Feireisl, Eduard

    2016-01-01

    Roč. 9, č. 1 (2016), s. 173-183 ISSN 1937-1632 R&D Projects: GA ČR GA13-00522S Institutional support: RVO:67985840 Keywords : Euler-Cahn-Hilliard system * weak solution * diffuse interface model Subject RIV: BA - General Mathematics Impact factor: 0.781, year: 2016 http://aimsciences.org/journals/displayArticlesnew.jsp?paperID=12093

  3. Generic aspects of salt repositories

    International Nuclear Information System (INIS)

    Laughon, R.B.

    1979-01-01

    The history of geological disposal of radioactive wastes in salt is presented from 1957 when a panel of the National Academy of Sciences-National Research Council recommended burial in bedded salt deposits. Early work began in the Kansas, portion of the Permian Basin where simulated wastes were placed in an abandoned salt mine at Lyons, Kansas, in the late 1960's. This project was terminated when the potential effect of nearby solution mining activities could not be resolved. Evaluation of bedded salts resumed a few years later in the Permian Basin in southeastern New Mexico, and search for suitable sites in the 1970's resulted in the formation of the National Waste Terminal Storage Program in 1976. Evaluation of salt deposits in many regions of the United States has been virtually completed and has shown that deposits having the greatest potential for radioactive waste disposal are those of the largest depositional basins and salt domes of the Gulf Coast region

  4. Micro-Arc oxidation of Ti in a solution of sulfuric acid and Ti+3 salt

    International Nuclear Information System (INIS)

    Ragalevicius, Rimas; Stalnionis, Giedrius; Niaura, Gediminas; Jagminas, Arunas

    2008-01-01

    A comparative study was performed on the behavior of titanium electrode in a sulfuric acid solution with and without Ti +3 during micro-arc oxidation under the constant current density control regime. The composition and microstructure of the obtained micro-arc films were analyzed using scanning electron microscopy, glancing-angle X-ray diffractometry, Raman and energy-dispersive X-ray spectroscopies. We have shown that addition of a Ti +3 salt extends the region of current densities (j a ) can be used for micro-arc oxidation of Ti and results in an obvious change of sparking behavior from extensive, large and long-played sparks to numerous, small and short sparks. As a consequence, the titania films formed in the Ti +3 -containing solutions are relatively thick, more uniform, composed of almost pure crystalline anatase and rutile phases of TiO 2 , and contain a network of evenly distributed small pores. It has also been shown that these films are promising for applications in catalysis, sensors and optoelectronics. The Raman spectra indicate that an increase in the electrolysis time of titanium in the Ti +3 -containing solution leads to the increase in rutile content, as expected

  5. Physico-chemistry of actinides and other radioelements in solutions and at the interfaces

    International Nuclear Information System (INIS)

    2000-01-01

    This document provides the 61 papers (transparencies used during the presentations and posters) presented at the 1999 PRACTIS days, held February 17-18, 2000 in Villeneuve-les-Avignon. The content comprises 9 conferences dealing with 1)simulation of solvation, coordination and liquid-liquid extraction of rare earth and uranyl cations 2)overview on the complexation selectivity of actinides(III) and rare earths(III) by aromatic poly-nitrogenous ligands 3)detection, characterization and interaction between supramolecular aggregates of extractants: macroscopic consequences on the stability and on the macroscopic behaviour 4)chemistry of technetium in reducing medium: application to researches on radioactive waste management 5) separations by pyro-chemistry (CEA program) 6)overview on the Goethite operation 7)use of time-resolved luminescence spectroscopy to the determination of sorption sites at the interfaces 8)dissolution of uranium dioxide in an argillaceous water: results in oxidizing and reducing conditions 9)treatment and storage of radioactive wastes from weapon-grade plutonium production in Russia and other countries. A large part of the conference was devoted to poster sessions on the following topics: physico-chemistry in homogeneous solutions (22 posters), transfer kinetics of actinides and rare earths between liquid phases and separations (9 posters), physico-chemistry of the solid-solution interface (9 posters), simulation and molecular dynamics (5 posters), uranium dioxide and other oxides (1 poster), long-lived fission products (6 posters). (O.M.)

  6. Structural analysis of salt cavities formed by solution mining: I. Method of analysis and preliminary results for spherical cavities

    International Nuclear Information System (INIS)

    Fossum, A.F.

    1976-01-01

    The primary objective of this effort is an analysis of the structural stability of cavities formed by solution mining in salt domes. In particular, the effects of depth (i.e. initial state of in situ stress), shape, volume (i.e. physical dimensions of the cavity), and sequence of salt excavation/fluid evacuation on the timewise structural stability of a cavity are of interest. It is anticipated that an assessment can be made of the interrelation between depth, cavern size, and cavern shape or of the practical limits therewith. In general, the cavity shape is assumed to be axisymmetric and the salt is assumed to exhibit nonlinear creep behavior. The primary emphasis is placed on the methodology of the finite element analysis, and the results of preliminary calculations for a spherically shaped cavity. It is common practice for engineers to apply elasticity theory to the behavior of rock in order to obtain near field stresses and displacements around an underground excavation in an effort to assess structural stability. Rock masses, particularly at depth, may be subjected to a rather complex state of initial stress, and may be nonhomogeneous and anisotropic. If one also includes complex geometrical excavation shape, the use of analytical techniques as an analysis tool is practically impossible. Thus, it is almost a necessity that approximate solution techniques be employed. In this regard, the finite element method is ideal as it can handle complex geometries and nonlinear material behavior with relative ease. An unusual feature of the present study is the incorporation into the finite element code of a procedure for handling the gradual creation or excavation of an underground cavity. During the excavation sequence, the salt is permitted to exhibit nonlinear stress-strain-time dependence. The bulk of this report will be devoted to a description of the analysis procedures, together with a preliminary calculation for a spherically shaped cavity

  7. Measurement of emittance of metal interface in molten salt

    International Nuclear Information System (INIS)

    Araki, N.; Makino, A.; Nakamura, Y.

    1995-01-01

    A new technique for measuring the total normal emittance of a metal in a semi-transparent liquid has been proposed and this technique has been applied to measure the emittance of stainless steel (SUS304), nickel, and gold in molten potassium nitrate KNO 3 . These emittance data are indispensable to analyzing the radiative heat transfer between a metal and a semitransparent liquid, such as a molten salt

  8. 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.

  9. Heat Transfer from Optically Excited Gold Nanostructures into Water, Sugar, and Salt Solutions

    Science.gov (United States)

    Green, Andrew J.

    coherence length associated with the liquid-liquid transition. The second topic will measure the change in heat dissipation with respect to solute adhesion onto the nanoheater. A small amount of aqueous solute molecules (1 solute molecule in 550 water molecules) dramatically increases the heat dissipation from a nanoparticle into the surrounding liquid. This result is consistent with a thermal conductance that is limited by an interface interaction where minority aqueous components significantly alter the surface properties and heat transport through the interface. The increase in heat dissipation can be used to make an extremely sensitive molecular detector that can be scaled to give single molecule detection without amplification or utilizing fluorescence labels.

  10. The enigma of cooking salt crystals

    International Nuclear Information System (INIS)

    Nikolskaya, E.

    1987-01-01

    Two Soviet experts, Vladimir Gromov and Valentin Krylov, have discovered an unexpected phenomenon on irradiating cooking salt crystals with electrons. When the crystals are subsequently ground the rate at which they are dissolved increases, but not always. The electrons cause the salt molecules to polarize thus creating an internal electric field. This acts against the double electric layer which is inevitably formed in the part of the solution touching the crystal surface. So, if the permittivity of the solution is much greater than that of the molecules of the crystal, the rate of dissolution is increased, and vice versa. (G.T.H.)

  11. Molten salt reactor type

    International Nuclear Information System (INIS)

    1977-01-01

    This document is one of the three parts of a first volume devoted to the compilations of American data on the molten salt reactor concept. Emphasize is put essentially on the fuel salt of the primary circuit inside which fission reactions occur. The reasons why the (LiF-BeF 2 -ThF 4 -UF 4 ) salt was chosen for the M.S.B.R. concept are examined; the physical, physicochemical and chemical properties of this salt are discussed with its interactions with the structural materials and its evolution in time. An important part of this volume is devoted to the continuous reprocessing of the active salt, the project designers having deemed advisable to take advantage at best from the availability of a continuous purification, in a thermal breeding. The problem of tritium formation and distribution inside the reactor is also envisaged and the fundamentals of the chemistry of the secondary coolant salt are given. The solutions proposed are: the hydrogen scavenging of the primary circuit, a reduction in metal permeability by an oxyde layer deposition on the side in contact with the vapor, and tritium absorption through an isotope exchange with the hydroxifluoroborate [fr

  12. 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

  13. Salt Concentration Differences Alter Membrane Resistance in Reverse Electrodialysis Stacks

    KAUST Repository

    Geise, Geoffrey M.

    2014-01-14

    Membrane ionic resistance is usually measured by immersing the membrane in a salt solution at a single, fixed concentration. While salt concentration is known to affect membrane resistance when the same concentration is used on both sides of the membrane, little is known about membrane resistance when the membrane is placed between solutions of different concentrations, such as in a reverse electrodialysis (RED) stack. Ionic resistance measurements obtained using Selemion CMV and AMV that separated sodium chloride and ammonium bicarbonate solutions of different concentrations were greater than those measured using only the high-concentration solution. Measured RED stack resistances showed good agreement with resistances calculated using an equivalent series resistance model, where the membranes accounted for 46% of the total stack resistance. The high area resistance of the membranes separating different salt concentration solutions has implications for modeling and optimizing membranes used in RED systems.

  14. Equilibrium of adsorption of mixed milk protein/surfactant solutions at the water/air interface.

    Science.gov (United States)

    Kotsmar, C; Grigoriev, D O; Xu, F; Aksenenko, E V; Fainerman, V B; Leser, M E; Miller, R

    2008-12-16

    Ellipsometry and surface profile analysis tensiometry were used to study and compare the adsorption behavior of beta-lactoglobulin (BLG)/C10DMPO, beta-casein (BCS)/C10DMPO and BCS/C12DMPO mixtures at the air/solution interface. The adsorption from protein/surfactant mixed solutions is of competitive nature. The obtained adsorption isotherms suggest a gradual replacement of the protein molecules at the interface with increasing surfactant concentration for all studied mixed systems. The thickness, refractive index, and the adsorbed amount of the respective adsorption layers, determined by ellipsometry, decrease monotonically and reach values close to those for a surface covered only by surfactant molecules, indicating the absence of proteins from a certain surfactant concentration on. These results correlate with the surface tension data. A continuous increase of adsorption layer thickness was observed up to this concentration, caused by the desorption of segments of the protein and transforming the thin surface layer into a rather diffuse and thick one. Replacement and structural changes of the protein molecules are discussed in terms of protein structure and surface activity of surfactant molecules. Theoretical models derived recently were used for the quantitative description of the equilibrium state of the mixed surface layers.

  15. First-principles calculations of the thermodynamic properties of transuranium elements in a molten salt medium

    International Nuclear Information System (INIS)

    Noh, Seunghyo; Kwak, Dohyun; Lee, Juseung; Kang, Joonhee; Han, Byungchan

    2014-01-01

    We utilized first-principles density-functional-theory (DFT) calculations to evaluate the thermodynamic feasibility of a pyroprocessing methodology for reducing the volume of high-level radioactive materials and recycling spent nuclear fuels. The thermodynamic properties of transuranium elements (Pu, Np and Cm) were obtained in electrochemical equilibrium with a LiCl-KCl molten salt as ionic phases and as adsorbates on a W(110) surface. To accomplish the goal, we rigorously calculated the double layer interface structures on an atomic resolution, on the thermodynamically most stable configurations on W(110) surfaces and the chemical activities of the transuranium elements for various coverages of those elements. Our results indicated that the electrodeposition process was very sensitive to the atomic level structures of Cl ions at the double-layer interface. Our studies are easily expandable to general electrochemical applications involving strong redox reactions of transition metals in non-aqueous solutions.

  16. Anomalous Protein-Protein Interactions in Multivalent Salt Solution

    Czech Academy of Sciences Publication Activity Database

    Pasquier, C.; Vazdar, M.; Forsman, J.; Jungwirth, Pavel; Lund, M.

    2017-01-01

    Roč. 121, č. 14 (2017), s. 3000-3006 ISSN 1520-6106 R&D Projects: GA ČR(CZ) GA16-01074S Institutional support: RVO:61388963 Keywords : Monte Carlo * molecular dynamics * membranes * proteins * multivalent salts Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 3.177, year: 2016

  17. Saturated salt solution method: a useful cadaver embalming for surgical skills training.

    Science.gov (United States)

    Hayashi, Shogo; Homma, Hiroshi; Naito, Munekazu; Oda, Jun; Nishiyama, Takahisa; Kawamoto, Atsuo; Kawata, Shinichi; Sato, Norio; Fukuhara, Tomomi; Taguchi, Hirokazu; Mashiko, Kazuki; Azuhata, Takeo; Ito, Masayuki; Kawai, Kentaro; Suzuki, Tomoya; Nishizawa, Yuji; Araki, Jun; Matsuno, Naoto; Shirai, Takayuki; Qu, Ning; Hatayama, Naoyuki; Hirai, Shuichi; Fukui, Hidekimi; Ohseto, Kiyoshige; Yukioka, Tetsuo; Itoh, Masahiro

    2014-12-01

    This article evaluates the suitability of cadavers embalmed by the saturated salt solution (SSS) method for surgical skills training (SST). SST courses using cadavers have been performed to advance a surgeon's techniques without any risk to patients. One important factor for improving SST is the suitability of specimens, which depends on the embalming method. In addition, the infectious risk and cost involved in using cadavers are problems that need to be solved. Six cadavers were embalmed by 3 methods: formalin solution, Thiel solution (TS), and SSS methods. Bacterial and fungal culture tests and measurement of ranges of motion were conducted for each cadaver. Fourteen surgeons evaluated the 3 embalming methods and 9 SST instructors (7 trauma surgeons and 2 orthopedists) operated the cadavers by 21 procedures. In addition, ultrasonography, central venous catheterization, and incision with cauterization followed by autosuture stapling were performed in some cadavers. The SSS method had a sufficient antibiotic effect and produced cadavers with flexible joints and a high tissue quality suitable for SST. The surgeons evaluated the cadavers embalmed by the SSS method to be highly equal to those embalmed by the TS method. Ultrasound images were clear in the cadavers embalmed by both the methods. Central venous catheterization could be performed in a cadaver embalmed by the SSS method and then be affirmed by x-ray. Lungs and intestines could be incised with cauterization and autosuture stapling in the cadavers embalmed by TS and SSS methods. Cadavers embalmed by the SSS method are sufficiently useful for SST. This method is simple, carries a low infectious risk, and is relatively of low cost, enabling a wider use of cadavers for SST.

  18. A note on the standard electron transfer potential at the interface between two immiscible electrolyte solutions

    Czech Academy of Sciences Publication Activity Database

    Samec, Zdeněk

    2009-01-01

    Roč. 55, č. 2 (2009), s. 75-81 ISSN 0034-6691 R&D Projects: GA ČR(CZ) GA203/07/1257 Institutional research plan: CEZ:AV0Z40400503 Keywords : interface between two immiscible electrolyte solutions * interfacial electron transfer * standard electron trasfer potential * homogeneous electron transfer Subject RIV: CG - Electrochemistry

  19. Removal of Cr(III ions from salt solution by nanofiltration: experimental and modelling analysis

    Directory of Open Access Journals (Sweden)

    Kowalik-Klimczak Anna

    2016-09-01

    Full Text Available The aim of this study was experimental and modelling analysis of the nanofiltration process used for the removal of chromium(III ions from salt solution characterized by low pH. The experimental results were interpreted with Donnan and Steric Partitioning Pore (DSP model based on the extended Nernst-Planck equation. In this model, one of the main parameters, describing retention of ions by the membrane, is pore dielectric constant. In this work, it was identified for various process pressures and feed compositions. The obtained results showed the satisfactory agreement between the experimental and modelling data. It means that the DSP model may be helpful for the monitoring of nanofiltration process applied for treatment of chromium tannery wastewater.

  20. Reactivity of nitrate and organic acids at the concrete–bitumen interface of a nuclear waste repository cell

    Energy Technology Data Exchange (ETDEWEB)

    Bertron, A., E-mail: bertron@insa-toulouse.fr [Université de Toulouse (France); UPS, INSA (France); LMDC (Laboratoire Matériaux et Durabilité des Constructions), 135, avenue de Rangueil, F-31 077, Toulouse Cedex 04 (France); Jacquemet, N. [Université de Toulouse (France); UPS, INSA (France); LMDC (Laboratoire Matériaux et Durabilité des Constructions), 135, avenue de Rangueil, F-31 077, Toulouse Cedex 04 (France); Erable, B. [Université de Toulouse (France); INPT, UPS (France); CNRS, Laboratoire de Génie Chimique, 4, Allée Emile Monso, F-31030 Toulouse (France); Sablayrolles, C. [Université de Toulouse (France); INP (France); LCA (Laboratoire de Chimie Agro-Industrielle), ENSIACET, 4 allée Emile Monso, BP 44 362, 31432 Toulouse Cedex 4 (France); INRA (France); LCA (Laboratoire de Chimie Agro-Industrielle), F-31029 Toulouse (France); Escadeillas, G. [Université de Toulouse (France); UPS, INSA (France); LMDC (Laboratoire Matériaux et Durabilité des Constructions), 135, avenue de Rangueil, F-31 077, Toulouse Cedex 04 (France); Albrecht, A. [Andra, 1-7, rue Jean-Monnet, 92298 Châtenay-Malabry (France)

    2014-03-01

    Highlights: • Interactions of cement paste and organic acid–nitrate solutions were investigated. • Cement leaching imposed alkaline pH (>10) very rapidly in the liquid media. • Acetic acid action on cement paste was similar to that of classical leaching. • Oxalic acid attack formed Ca-oxalate salts; organic matter in solution decreased. • Nitrate was stable under abiotic conditions and with organic matter. - Abstract: This study investigates the fate of nitrate and organic acids at the bitumen–concrete interface within repository cell for long-lived, intermediate-level, radioactive wastes. The interface was simulated by a multiphase system in which cementitious matrices (CEM V cement paste specimens) were exposed to bitumen model leachates consisting of nitrates and acetic acid with and without oxalic acid, chemical compounds likely to be released by bitumen. Leaching experiments were conducted with daily renewal of the solutions in order to accelerate reactions. The concentrations of anions (acetate, oxalate, nitrate, and nitrite) and cations (calcium, potassium) and the pH were monitored over time. Mineralogical changes of the cementitious matrices were analysed by XRD. The results confirmed the stability of nitrates in the abiotic conditions of the experiments. The action of acetic acid on the cementitious matrix was similar to that of ordinary leaching in the absence of organic acids (i.e. carried out with water or strong acids); no specific interaction was detected between acetate and cementitious cations. The reaction of oxalic acid with the cementitious phases led to the precipitation of calcium oxalate salts in the outer layer of the matrix. The concentration of oxalate was reduced by 65% inside the leaching medium.

  1. Degradation of lead-based pigments by salt solutions

    Czech Academy of Sciences Publication Activity Database

    Kotulanová, Eva; Bezdička, Petr; Hradil, David; Hradilová, J.; Švarcová, Silvie; Grygar, Tomáš

    2009-01-01

    Roč. 10, č. 3 (2009), s. 367-378 ISSN 1296-2074 R&D Projects: GA ČR(CZ) GA203/07/1324; GA AV ČR KJB400320602 Institutional research plan: CEZ:AV0Z40320502 Keywords : X-ray microdiffraction * salts * red lead Subject RIV: CA - Inorganic Chemistry Impact factor: 1.505, year: 2009

  2. 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

  3. 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

  4. Formation of magnetite (Fe3O4)in aqueous media and properties of the interface magnetite/solution

    International Nuclear Information System (INIS)

    Regazzoni, A.E.

    1984-01-01

    The formation of Fe 3 O 4 particles in aqueous media and the properties of the Fe 3 O 4 /aqueous solution interface are studied. This system is of particular interest in nuclear reactor chemistry, since Fe 3 O 4 was identified as the main component of the corrosion products of nuclear power plants cooled with pressurized water, of the Atucha I and II, and Embalse type. Four methods for the synthesis of Fe 3 O 4 are described: a) controlled oxidation of Fe(OH) 2 in the presence of NaNO 3 at 25 deg C; b) controlled oxidation of Fe(OH) 2 in the presence of NaNO 3 and N 2 H 4 and at 100 deg C; c) alkalinization of a F 2+ and Fe 3+ solutions at 80 deg C; d) simultaneous oxidation and alkalinization of a Fe 2+ . The interfacial properties of Fe 3 O 4 particles suspended in aqueous solutions of indifferent electrolytes are described. These properties are essential for the activity transport associated with the corrosion products. Finally, the adsorption of H 3 BO 3 , Hsub(n)PO 4 sup(n-3) and n Co(II) in the Fe 3 O 4 /solution interface at 30 deg C. It is concluded that the adsorbed species are chemically bonded to surface metal ions. (M.E.L.) [es

  5. 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.

  6. 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.

  7. Salt power - Is Neptune's ole salt a tiger in the tank

    Science.gov (United States)

    Wick, G. S.

    1980-02-01

    Methods of exploiting the 24 atm osmotic pressure difference between fresh and salt water to generate energy include reverse electrodialysis, wherein 80 millivolts of electricity cross each ion-selective membrane placed between solutions of fresh and salt water. Pressure-retarded osmosis, using pumps and pressure chambers, relies on semipermeable membranes that allow fresh water to flow into saline, with power generated by the permeated water being released through a turbine. In reverse vapor compression, water vapor rapidly transfers from fresh water to salt water in an evacuated chamber (due to the vapor pressure difference between them), and power can be extracted using 24 m diameter turbine blades. Environmental concerns include protecting estuaries from stress, managing sediments, and protecting marine animals, while filtration would be needed to keep the membranes free from corrosion, biological fouling, or silting.

  8. Chemical interactions and thermodynamic studies in aluminum alloy/molten salt systems

    Science.gov (United States)

    Narayanan, Ramesh

    The recycling of aluminum and aluminum alloys such as Used Beverage Container (UBC) is done under a cover of molten salt flux based on (NaCl-KCl+fluorides). The reactions of aluminum alloys with molten salt fluxes have been investigated. Thermodynamic calculations are performed in the alloy/salt flux systems which allow quantitative predictions of the equilibrium compositions. There is preferential reaction of Mg in Al-Mg alloy with molten salt fluxes, especially those containing fluorides like NaF. An exchange reaction between Al-Mg alloy and molten salt flux has been demonstrated. Mg from the Al-Mg alloy transfers into the salt flux while Na from the salt flux transfers into the metal. Thermodynamic calculations indicated that the amount of Na in metal increases as the Mg content in alloy and/or NaF content in the reacting flux increases. This is an important point because small amounts of Na have a detrimental effect on the mechanical properties of the Al-Mg alloy. The reactions of Al alloys with molten salt fluxes result in the formation of bluish purple colored "streamers". It was established that the streamer is liquid alkali metal (Na and K in the case of NaCl-KCl-NaF systems) dissipating into the melt. The melts in which such streamers were observed are identified. The metal losses occurring due to reactions have been quantified, both by thermodynamic calculations and experimentally. A computer program has been developed to calculate ternary phase diagrams in molten salt systems from the constituting binary phase diagrams, based on a regular solution model. The extent of deviation of the binary systems from regular solution has been quantified. The systems investigated in which good agreement was found between the calculated and experimental phase diagrams included NaF-KF-LiF, NaCl-NaF-NaI and KNOsb3-TINOsb3-LiNOsb3. Furthermore, an insight has been provided on the interrelationship between the regular solution parameters and the topology of the phase

  9. 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

  10. Line emissions from sonoluminescence in aqueous solutions of halide salts without noble gases

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Jinfu, E-mail: liang.shi2007@163.com [The Key Laboratory of Modern Acoustics, Ministry of Education, Institution of Acoustics, Nanjing University, Nanjing 210093 (China); School of Physics and Electronic Science, Guizhou Normal University, Guiyang 550001 (China); Chen, Weizhong, E-mail: wzchen@nju.edu.cn [The Key Laboratory of Modern Acoustics, Ministry of Education, Institution of Acoustics, Nanjing University, Nanjing 210093 (China); Zhou, Chao; Cui, Weicheng; Chen, Zhan [The Key Laboratory of Modern Acoustics, Ministry of Education, Institution of Acoustics, Nanjing University, Nanjing 210093 (China)

    2015-02-20

    Line emissions of trivalent terbium (Tb{sup 3+}) ion were observed from single-bubble sonoluminescence (SL) in an aqueous solution of terbium chloride (TbCl{sub 3}) that contained no noble gas. In addition, sodium (Na) lines were observed in multi-bubble SL in aqueous solutions of various halide salts that contained no noble gas. These observations show that the halide ions, such as Cl{sup −}, Br{sup −}, and I{sup −}, help for line emissions as the noble gases. The intensity of a line emission depends on both the chemical species produced by cavitation bubbles and the temperature of SL bubble that responds to the driving ultrasound pressure. With the increase of driving pressure, some line emissions attached to the continuous spectrum may become increasingly clear, while other line emissions gradually become indistinct. - Highlights: • Line emissions of Tb(III) ions were observed without the presence of noble gases. • The halide ions help to generate a line emission during sonoluminescence. • The intensity of a line emission mainly depends on the bubble's temperature. • The definition of a line emission is related to the temperature of caviation bubble and the kind of host liquid.

  11. Pressure-induced brine migration in consolidated salt in a repository

    International Nuclear Information System (INIS)

    Hwang, Y.; Chambre, P.L.; Lee, W.W.L.; Pigford, T.H.

    1987-06-01

    This report describes a mathematical model for brine migration through intact salt near a radioactive waste package emplaced in salt. Solutions indicate limited movement following ten years emplacement

  12. Crushed Salt Constitutive Model

    International Nuclear Information System (INIS)

    Callahan, G.D.

    1999-01-01

    The constitutive model used to describe the deformation of crushed salt is presented in this report. Two mechanisms -- dislocation creep and grain boundary diffusional pressure solution -- are combined to form the basis for the constitutive model governing the deformation of crushed salt. The constitutive model is generalized to represent three-dimensional states of stress. Upon complete consolidation, the crushed-salt model reproduces the Multimechanism Deformation (M-D) model typically used for the Waste Isolation Pilot Plant (WIPP) host geological formation salt. New shear consolidation tests are combined with an existing database that includes hydrostatic consolidation and shear consolidation tests conducted on WIPP and southeastern New Mexico salt. Nonlinear least-squares model fitting to the database produced two sets of material parameter values for the model -- one for the shear consolidation tests and one for a combination of the shear and hydrostatic consolidation tests. Using the parameter values determined from the fitted database, the constitutive model is validated against constant strain-rate tests. Shaft seal problems are analyzed to demonstrate model-predicted consolidation of the shaft seal crushed-salt component. Based on the fitting statistics, the ability of the model to predict the test data, and the ability of the model to predict load paths and test data outside of the fitted database, the model appears to capture the creep consolidation behavior of crushed salt reasonably well

  13. Radiation damage on Langmuir monolayers of the anionic 1.2-dipalmitoyl-sn-glycero-3-[phospho-rac-(1-glycerol)] (sodium salt)(DPPG) phospholipid at the air–DNA solution interface

    Energy Technology Data Exchange (ETDEWEB)

    Gomes, Paulo J. [CEFITEC, Departamento de Física, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Gonçalves da Silva, Amélia M.P.S. [Centro de Química Estrutural, Complexo I, Instituto Superior Técnico, Universidade de Lisboa, Av Rovisco Pais, 1049-001 Lisboa (Portugal); Ribeiro, Paulo A. [CEFITEC, Departamento de Física, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Oliveira, Osvaldo N. [Instituto de Física de São Carlos, Universidade de São Paulo, CP 369, 13560-970 São Carlos, São Paulo (Brazil); Raposo, Maria, E-mail: mfr@fct.unl.pt [CEFITEC, Departamento de Física, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal)

    2016-01-01

    The resilience of cells to ultraviolet (UV) irradiation is probably associated with the effects induced in biological molecules such as DNA and in the cell membrane. In this study, we investigated UV damage to the anionic 1.2-dipalmitoyl-sn-glycero-3-[phospho-rac-(1-glycerol)] (sodium salt) (DPPG) phospholipid, which is an important component of cell membranes. In films cast from DPPG emulsions, UV irradiation induced cleavage of C―O, C = O and ―PO{sup 2−} bonds, while in Langmuir monolayers at the air/water interface representing the cell membrane this irradiation caused the monolayer stability to decrease. When DNA was present in the subphase, however, the effects from UV irradiation were smaller, since the ionic products from degradation of either DPPG or DNA stabilize the intact DPPG molecules. This mechanism may explain why UV irradiation does not cause immediate cell collapse, thus providing time for the cellular machinery to repair elements damaged by UV. - Highlights: • UV induce cleavage of C―O, C=O and PO{sup 2−} bonds in DPPG molecules in the presence of water. • The stability of DPPG monolayers decreased when irradiated with UV. • UV effects were mitigated if DNA molecules were incorporated into subphase. • The ionic products resulting from UV degradation stabilize DPPG monolayer. • Such mechanism explain why cells do not collapse immediately after irradiation.

  14. 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)

  15. Buffer salt effects in off-line coupling of capillary electrophoresis and mass spectrometry.

    Science.gov (United States)

    Marák, Jozef; Stanová, Andrea

    2014-05-01

    In this work, the impact of buffer salts/matrix effects on the signal in direct injection MS with an electrospray interface (DI-ESI-MS) following pITP fractionation of the sample was studied. A range of buffers frequently used in CE analyses (pH 3-10) was prepared containing 10, 50, and 90% v/v of ACN, respectively. The sets of calibration solutions of cetirizine (an antihistaminic drug with an amphiprotic character) within a 0.05-2.0 mg/L concentration range were prepared in different buffers. The greatest enhancements in the MS signal (in terms of change in the slope of the calibration line) were obtained for the beta-alanine buffer (pH 3.5) in positive ionization and for the borate buffer (pH 9.2) in negative ionization, respectively. The procedure was successfully applied to the analysis of buserelin (a peptidic drug). The slope of the calibration line for solutions containing the beta-alanine buffer with 50% of ACN was 4 times higher than for water or urine, respectively. This study clearly demonstrates that the buffer salt/matrix effects in an offline combination of pITP and DI-ESI-MS can also play a positive role, as they can enhance the signal in MS. A similar influence of the above effects can also be presumed in the CE techniques combined on-line with ESI-MS.

  16. 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....

  17. Origin of salt giants in abyssal serpentinite systems

    Science.gov (United States)

    Scribano, Vittorio; Carbone, Serafina; Manuella, Fabio C.; Hovland, Martin; Rueslåtten, Håkon; Johnsen, Hans-K.

    2017-10-01

    Worldwide marine salt deposits ranging over the entire geological record are generally considered climate-related evaporites, derived from the precipitation of salts (mainly chlorides and sulfates) from saturated solutions driven by solar evaporation of seawater. This explanation may be realistic for a salt thickness ≤100 m, being therefore inadequate for thicker (>1 km) deposits. Moreover, sub-seafloor salt deposits in deep marine basins are difficult to reconcile with a surface evaporation model. Marine geology reports on abyssal serpentinite systems provide an alternative explanation for some salt deposits. Seawater-driven serpentinization consumes water and increases the salinity of the associated aqueous brines. Brines can be trapped in fractures and cavities in serpentinites and the surrounding `country' rocks. Successive thermal dehydration of buried serpentinites can mobilize and accumulate the brines, forming highly saline hydrothermal solutions. These can migrate upwards and erupt onto the seafloor as saline geysers, which may form salt-saturated water pools, as are currently observed in numerous deeps in the Red Sea and elsewhere. The drainage of deep-seated saline brines to seafloor may be a long-lasting, effective process, mainly occurring in areas characterized by strong tectonic stresses and/or igneous intrusions. Alternatively, brines could be slowly expelled from fractured serpentinites by buoyancy gradients and, hence, separated salts/brines could intrude vertically into surrounding rocks, forming salt diapirs. Serpentinization is an ubiquitous, exothermic, long-lasting process which can modify large volumes of oceanic lithosphere over geological times. Therefore, buried salt deposits in many areas of the world can be reasonably related to serpentinites.

  18. The material flow of salt

    International Nuclear Information System (INIS)

    Kostick, D.S.

    1993-01-01

    Salt (NaCl) is a universal mineral commodity used by virtually every person in the world. Although a very common mineral today, at one time it was considered as precious as gold in certain cultures. This study traces the material flow of salt from its origin through the postconsumer phase of usage. The final disposition of salt in the estimated 14,000 different uses, grouped into several macrocategories, is traced from the dispersive loss of salt into the environment to the ultimate disposal of salt-base products into the waste stream after consumption. The base year for this study is 1990, in which an estimated 196 million short tons of municipal solid waste was discarded by the US population. Approximately three-fourths of domestic salt consumed is released to the environment and unrecovered while about one-fourth is discharged to landfills and incinerators as products derived from salt. Cumulative historical domestic production, trade, and consumption data have been compiled to illustrate the long-term trends within the US salt industry and the cumulative contribution that highway deicing salt has had on the environment. Salt is an important component of drilling fluids in well drilling. It is used to flocculate and to increase the density of the drilling fluid in order to overcome high down-well gas pressures. Whenever drilling activities encounter salt formations, salt is added to the drilling fluid to saturate the solution and minimize the dissolution within the salt strata. Salt is also used to increase the set rate of concrete in cemented casings. This subsector includes companies engaged in oil, gas, and crude petroleum exploration and in refining and compounding lubricating oil. It includes SIC major groups 13 and 29. 13 refs., 14 figs., 6 tabs

  19. Electrolytic experiments of gadolinium and neodymium ions in the fluoride molten salt

    International Nuclear Information System (INIS)

    Sim, J. B.; Hwang, S. C.; Kim, W. H.; Kang, Y. H.; Lee, B. J.; Yoo, J. H.

    2002-01-01

    Electrolytic reductions of Gd 3+ and Nd 3+ ions were carried out to prepare bismuth alloys including Gd and Nd solutes using a molten liquid Bi cathode in the LiF-NaF-KF fluoride salt. It was considered that selective separation of Gd from bismuth alloy is possible by controlling the addition amount of an oxidation agent to a salt phase. Cyclic voltammetry measurements are useful tools not only for in-situ detection of solutes in salt phase in the course of back extraction experiments but also for elucidation of electrochemical reactions of Gd and Nd in the FLINAK molten salt

  20. 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.

  1. Hygroscopic salts and the potential for life on Mars.

    Science.gov (United States)

    Davila, Alfonso F; Duport, Luis Gago; Melchiorri, Riccardo; Jänchen, Jochen; Valea, Sergio; de Los Rios, Asunción; Fairén, Alberto G; Möhlmann, Diedrich; McKay, Christopher P; Ascaso, Carmen; Wierzchos, Jacek

    2010-01-01

    Hygroscopic salts have been detected in soils in the northern latitudes of Mars, and widespread chloride-bearing evaporitic deposits have been detected in the southern highlands. The deliquescence of hygroscopic minerals such as chloride salts could provide a local and transient source of liquid water that would be available for microorganisms on the surface. This is known to occur in the Atacama Desert, where massive halite evaporites have become a habitat for photosynthetic and heterotrophic microorganisms that take advantage of the deliquescence of the salt at certain relative humidity (RH) levels. We modeled the climate conditions (RH and temperature) in a region on Mars with chloride-bearing evaporites, and modeled the evolution of the water activity (a(w)) of the deliquescence solutions of three possible chloride salts (sodium chloride, calcium chloride, and magnesium chloride) as a function of temperature. We also studied the water absorption properties of the same salts as a function of RH. Our climate model results show that the RH in the region with chloride-bearing deposits on Mars often reaches the deliquescence points of all three salts, and the temperature reaches levels above their eutectic points seasonally, in the course of a martian year. The a(w) of the deliquescence solutions increases with decreasing temperature due mainly to the precipitation of unstable phases, which removes ions from the solution. The deliquescence of sodium chloride results in transient solutions with a(w) compatible with growth of terrestrial microorganisms down to 252 K, whereas for calcium chloride and magnesium chloride it results in solutions with a(w) below the known limits for growth at all temperatures. However, taking the limits of a(w) used to define special regions on Mars, the deliquescence of calcium chloride deposits would allow for the propagation of terrestrial microorganisms at temperatures between 265 and 253 K, and for metabolic activity (no growth) at

  2. 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.

  3. Mechanical modeling of the growth of salt structures

    Energy Technology Data Exchange (ETDEWEB)

    Alfaro, Ruben Alberto Mazariegos [Texas A & M Univ., College Station, TX (United States)

    1993-05-01

    A 2D numerical model for studying the morphology and history of salt structures by way of computer simulations is presented. The model is based on conservation laws for physical systems, a fluid marker equation to keep track of the salt/sediments interface, and two constitutive laws for rocksalt. When buoyancy alone is considered, the fluid-assisted diffusion model predicts evolution of salt structures 2.5 times faster than the power-law creep model. Both rheological laws predict strain rates of the order of 4.0 x 10-15 s-1 for similar structural maturity level of salt structures. Equivalent stresses and viscosities predicted by the fluid-assisted diffusion law are 102 times smaller than those predicted by the power-law creep rheology. Use of East Texas Basin sedimentation rates and power-law creep rheology indicate that differential loading is an effective mechanism to induce perturbations that amplify and evolve to mature salt structures, similar to those observed under natural geological conditions.

  4. Rheological stratification of the Hormuz Salt Formation in Iran - microstructural study of the dirty and pure rock salts from the Kuh-e-Namak (Dashti) salt diapir

    Science.gov (United States)

    Závada, Prokop; Desbois, Guillaume; Urai, Janos; Schulmann, Karel; Rahmati, Mahmoud; Lexa, Ondrej; Wollenberg, Uwe

    2014-05-01

    Significant viscosity contrasts displayed in flow structures of a mountain namakier (Kuh-e-Namak - Dashti), between 'weak' terrestrial debris bearing rock salt types and 'strong' pure rock salt types are questioned for deformation mechanisms using detailed quantitative microstructural study including crystallographic preferred orientation (CPO) mapping of halite grains. While the solid impurity rich ("dirty") rock salts contain disaggregated siltstone and dolomite interlayers, "clean" salts (debris free) reveal microscopic hematite and remnants of abundant fluid inclusions in non-recrystallized cores of porphyroclasts. Although flow in both, the recrystallized dirty and clean salt types is accommodated by combined mechanisms of pressure-solution creep (PS), grain boundary sliding (GBS) and dislocation creep accommodated grain boundary migration (GBM), their viscosity contrasts are explained by significantly slower rates of intergranular diffusion and piling up of dislocations at hematite inclusions in clean salt types. Porphyroclasts of clean salts deform by semi-brittle and plastic mechanisms with intra-crystalline damage being induced also by fluid inclusions that explode in the crystals at high fluid pressures. Boudins of clean salt types with coarse grained and original sedimentary microstructure suggest that clean rock salts are associated with dislocation creep dominated power law flow in the source layer and the diapiric stem. Rheological contrasts between both rock salt classes apply in general for the variegated and terrestrial debris rich ("dirty") Lower Hormuz and the "clean" rock salt forming the Upper Hormuz, respectively, and suggest that large strain rate gradients likely exist along horizons of mobilized salt types of different composition and microstructure.

  5. Salt effects on isotope partitioning and their geochemical implications: An overview

    International Nuclear Information System (INIS)

    Horita, J.; Cole, D.R.; Fortier, S.M.

    1996-01-01

    Essential to the use of stable isotopes as natural tracers and geothermometers is the knowledge of equilibrium isotope partitioning between different phases and species, which is usually a function of temperature only. The one exception known to date is oxygen and hydrogen isotope fractionation between liquid water and other phases (steam, gases, minerals), which changes upon the addition of salts to water, i.e., the isotope salt salt effect. Our knowledge of this effect, the difference between activity and composition (a-X) of isotopic water molecules in salt solutions, is very limited and controversial, especially at elevated temperatures. For the last several years, we have been conducting a detailed, systematic experimental study at Oak Ridge National Laboratory to determine the isotope salt effects from room temperature to elevated temperatures (currently to 500 degree C). From this effort, a simple, coherent picture of the isotope salt effect is emerging, that differs markedly from the complex results reported in the literature. In this communication, we present an overview on the isotope salt effect, obtained chiefly from our study. Observed isotope salt effects in salt solutions are significant even at elevated temperatures. The importance and implications of the isotope salt effect for isotopic studies of brine-dominated systems are also discussed in general terms

  6. Supramolecular Complexes Formed in Systems Bile Salt-Bilirubin-Silica

    Science.gov (United States)

    Vlasova, N. N.; Severinovskaya, O. V.; Golovkova, L. P.

    The formation of supramolecular complexes between bilirubin and primary micelles of bile salts has been studied. The association constants of bile salts and binding of bilirubin with these associates have been determined. The adsorption of bilirubin and bile salts from individual and mixed aqueous solutions onto hydrophobic silica surfaces has been investigated. The interaction of bilirubin with primary bile salt micelles and the strong retention in mixed micelles, which are supramolecular complexes, result in the adsorption of bilirubin in free state only.

  7. 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...

  8. Yttria hydroxy-salt binders

    International Nuclear Information System (INIS)

    Holcombe, C.E. Jr.

    1978-01-01

    Binder phase (primarily chloride or nitrate) formation was examined in YX 3 --NaOH--H 2 O, Y 2 O 3 --acid--H 2 O, and Y 2 O 3 --salt--H 2 O systems. The cementitious phase consisted mostly of plate- (or needle-) shaped hydroxy salts of the general formula Y 2 (OH)/sub 6-m/X/sub m/ nH 2 O, where m and n normally equal one. These binders were examined by x-ray diffraction and thermal analysis techniques. Nitrate binders decompose to Y 2 O 3 by 600 0 C, whereas chloride binders form oxychlorides that sublime or convert to Y 2 O 3 after oxygen replacement of chlorine (in air) at > 1000 0 C. Although nitric and hydrochloric acid solutions form porous ( 2 O 3 powder, salt solutions (i.e., NH 4 NO 3 , Mg(NO 3 ) 2 , NH 4 Cl, and YCl 3 approx. = 6H 2 O) slow the reaction considerably (48 h to 4 weeks), allowing 70- to 80%-dense cements to form. The effects of formation conditions on physical properties of binders were studied. Examination of scandium and lanthanide oxides showed that several behave in the same way as yttria

  9. Limiting salt crystallization damage in lime mortar by using crystallization modifiers

    NARCIS (Netherlands)

    Granneman, S.J.C.; Shahidzadeh, N.; Lubelli, B.A.; Hees, R.P.J. van

    2014-01-01

    Salt crystallization is a recurrent cause of damage in porous building materials. Lime-based mortars, which were widely used in construction of ancient masonry, are especially prone to salt damage, due to their low mechanical strength. Existing solutions to tackle salt damage in mortars have been

  10. Studies of extractant molecules in solution and at liquid-liquid interfaces: structural and mechanistic aspects of synergy effects

    International Nuclear Information System (INIS)

    Baaden, Marc

    2000-01-01

    Molecular dynamics simulations reported herein provide new important insights into cation recognition and complexation in solution as well as liquid-liquid extraction, with a particular focus on the microscopic events taking place at the interface between two immiscible liquids. Preliminary studies concerned the representation of the trivalent rare earth cations La 3+ , Eu 3+ and Yb 3+ in force field simulations, probing structural and energetic features on an experimentally characterized model system based on substituted pyridine dicarboxamide ligands. Complexation of such cations by a novel calixarene derivative was investigated showing unexpected features, such as the position of the cation in the complex. Independent experimental studies published subsequently support these findings. Another part of the work is related to industrial liquid-liquid extraction systems using tri-n-butyl phosphate (TBP) as co-solvent, extractant, surfactant and synergist. We investigate 1) concentration effects simulating up to 60 TBP at a water/chloroform interface, 2) acidity using a neutral and ionic model of HNO 3 and 3) synergistic aspects of mixed TBP/calixarene extraction systems. These simulations provide the first microscopic insights into such issues. We finally addressed the topic of solute transfer across the water/chloroform interface. The potential of mean force for such a process has been calculated by both standard methods and novel approaches [fr

  11. Geological Feasibility of Underground Oil Storage in Jintan Salt Mine of China

    Directory of Open Access Journals (Sweden)

    Xilin Shi

    2017-01-01

    Full Text Available A number of large underground oil storage spaces will be constructed in deep salt mines in China in the coming years. According to the general geological survey, the first salt cavern oil storage base of China is planned to be built in Jintan salt mine. In this research, the geological feasibility of the salt mine for oil storage is identified in detail as follows. (1 The characteristics of regional structure, strata sediment, and impermeable layer distribution of Jintan salt mine were evaluated and analyzed. (2 The tightness of cap rock was evaluated in reviews of macroscopic geology and microscopic measuring. (3 According to the geological characteristics of Jintan salt mine, the specific targeted formation for building underground oil storage was chosen, and the sealing of nonsalt interlayers was evaluated. (4 Based on the sonar measuring results of the salt caverns, the characteristics of solution mining salt caverns were analyzed. In addition, the preferred way of underground oil storage construction was determined. (5 Finally, the results of closed well observation in solution mining salt caverns were assessed. The research results indicated that Jintan salt mine has the basic geological conditions for building large-scale underground oil storage.

  12. Crystalline oxides on semiconductors: A structural transition of the interface phase

    Science.gov (United States)

    Walker, F. J.; Buongiorno-Nardelli, Marco; Billman, C. A.; McKee, R. A.

    2004-03-01

    The growth of crystalline oxides on silicon is facilitated by the preparation of a surface phase of alkaline earth silicide. We describe how the surface phase serves as a precursor of the final interface phase using reflection high energy electron diffraction (RHEED) and density functional theory (DFT). RHEED intensity oscillations of the growth of BaSrO show layer-by-layer build up of the oxide on the interface. The 2x1 symmetry of the surface precursor persists up to 3 ML BaSrO coverage at which point a 1x1 pattern characteristic of the rock-salt structure of BaSrO is observed. Prior to 3 ML growth of alkaline earth oxide, DFT calculations and RHEED show that the surface precursor persists as the interface phase and induces large displacements in the growing oxide layer away from the rock-salt structure and having a 2x1 symmetry. These distortions of the rock-salt structure are energetically unfavorable and become more unfavorable as the oxide thickness increases. At 3 ML, the stability of the rock-salt structure drives a structural transformation of the film and the interface phase to a structure that is distinct from the surface precursor. Research sponsored jointly by the Division of Materials Sciences and Engineering, Office of Basic Energy Sciences, U.S. Department of Energy at Oak Ridge National Laboratory under contract DE-AC05-00OR22725 with UT-Battelle, LLC and at the University of Tennessee under contract DE-FG02-01ER45937. Calculations have been performed on CCS supercomputers at Oak Ridge National Laboratory.

  13. Effects of salt pond restoration on benthic flux: Sediment as a source of nutrients to the water column

    Science.gov (United States)

    Topping, Brent R.; Kuwabara, James S.; Carter, James L.; Garrettt, Krista K.; Mruz, Eric; Piotter, Sarah; Takekawa, John Y.

    2016-01-01

    Understanding nutrient flux between the benthos and the overlying water (benthic flux) is critical to restoration of water quality and biological resources because it can represent a major source of nutrients to the water column. Extensive water management commenced in the San Francisco Bay, Beginning around 1850, San Francisco Bay wetlands were converted to salt ponds and mined extensively for more than a century. Long-term (decadal) salt pond restoration efforts began in 2003. A patented device for sampling porewater at varying depths, to calculate the gradient, was employed between 2010 and 2012. Within the former ponds, the benthic flux of soluble reactive phosphorus and that of dissolved ammonia were consistently positive (i.e., moving out of the sediment into the water column). The lack of measurable nitrate or nitrite concentration gradients across the sediment-water interface suggested negligible fluxes for dissolved nitrate and nitrite. The dominance of ammonia in the porewater indicated anoxic sediment conditions, even at only 1 cm depth, which is consistent with the observed, elevated sediment oxygen demand. Nearby openestuary sediments showed much lower benthic flux values for nutrients than the salt ponds under resortation. Allochthonous solute transport provides a nutrient advective flux for comparison to benthic flux. For ammonia, averaged for all sites and dates, benthic flux was about 80,000 kg/year, well above the advective flux range of −50 to 1500 kg/year, with much of the variability depending on the tidal cycle. By contrast, the average benthic flux of soluble reactive phosphorus was about 12,000 kg/year, of significant magnitude, but less than the advective flux range of 21,500 to 30,000 kg/year. These benthic flux estimates, based on solute diffusion across the sediment-water interface, reveal a significant nutrient source to the water column of the pond which stimulates algal blooms (often autotrophic). This benthic source may be

  14. The chemistry of salt-affected soils and waters

    Science.gov (United States)

    Knowledge of the chemistry of salt affected soils and waters is necessary for management of irrigation in arid and semi-arid regions. In this chapter we review the origin of salts in the landscape, the major chemical reactions necessary for prediction of the soil solution composition, and the use of...

  15. Evaluation of layered zinc hydroxide nitrate and zinc/nickel double hydroxide salts in the removal of chromate ions from solutions

    Science.gov (United States)

    de Oliveira, Henrique Bortolaz; Wypych, Fernando

    2016-11-01

    Layered zinc hydroxide nitrate (ZnHN) and Zn/Ni layered double hydroxide salts were synthesized and used to remove chromate ions from solutions at pH 8.0. The materials were characterized by many instrumental techniques before and after chromate ion removal. ZnHN decomposed after contact with the chromate solution, whereas the layered structure of Zn/Ni hydroxide nitrate (Zn/NiHN) and Zn/Ni hydroxide acetate (Zn/NiHA) remained their layers intact after the topotactic anionic exchange reaction, only changing the basal distances. ZnHN, Zn/NiHN, and Zn/NiHA removed 210.1, 144.8, and 170.1 mg of CrO42-/g of material, respectively. Although the removal values obtained for Zn/NiHN and Zn/NiHA were smaller than the values predicted for the ideal formulas of the solids (194.3 and 192.4 mg of CrO42-/g of material, respectively), the measured capacities were higher than the values achieved with many materials reported in the literature. Kinetic experiments showed the removal reaction was fast. To facilitate the solid/liquid separation process after chromium removal, Zn/Ni layered double hydroxide salts with magnetic supports were also synthesized, and their ability to remove chromate was evaluated.

  16. 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

  17. Molten-salt converter reactors

    International Nuclear Information System (INIS)

    Perry, A.M.

    1975-01-01

    Molten-salt reactors appear to have substantial promise as advanced converters. Conversion ratios of 0.85 to 0.9 should be attainable with favourable fuel cycle costs, with 235 U valued at $12/g. An increase in 235 U value by a factor of two or three ($10 to $30/lb. U 3 O 8 , $75/SWU) would be expected to increase the optimum conversion ratio, but this has not been analyzed in detail. The processing necessary to recover uranium from the fuel salt has been partially demonstrated in the MSRE. The equipment for doing this would be located at the reactor, and there would be no reliance on an established recycle industry. Processing costs are expected to be quite low, and fuel cycle optimization depends primarily on inventory and burnup or replacement costs for the fuel and for the carrier salt. Significant development problems remain to be resolved for molten-salt reactors, notably the control of tritium and the elimination of intergranular cracking of Hastelloy-N in contact with tellurium. However, these problems appear to be amenable to solution. It is appropriate to consider separating the development schedule for molten-salt reactors from that for the processing technology required for breeding. The Molten-Salt Converter Reactor should be a useful reactor in its own right and would be an advance towards the achievement of true breeding in thermal reactors. (author)

  18. New field of actinides solution chemistry; electrochemical study on actinide ion transfer at the interface of two immiscible electrolyte solutions

    Energy Technology Data Exchange (ETDEWEB)

    Kitatsuji, Yoshihiro; Yoshida, Zenko [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Kudo, Hiroshi [Tohoku Univ., Graduate School of Science, Sendai, Miyagi (Japan); Kihara, Sorin [Kyoto Inst. of Technolgy, Dept. of Chemistry, Kyoto (Japan)

    2002-04-01

    A novel electrochemical method on the basis of a controlled electrolysis has been developed for the study of the ion transfer at the interface of two immiscible electrolyte solutions (ITIES). The controlled-potential electrolysis for ITIES (CPEITIES) was applied to the transfer of actinide ions, and Gibbs energies for the transfer of UO{sub 2}{sup 2+} and Am{sup 3+} from aqueous solution (w) to nitrobenzene solution (nb) were determined to be 71.7 and 113 kJ mol{sup -1}, respectively. The ion transfer potentials for the facilitated transfer of UO{sub 2{sup +}} and Am{sup 3+} from w to nb in the presence of bis(diphenylphosphoryl)methane were determined, from which the stability constants of UO{sub 2}(BDPPM){sub 3}{sup 2+} and Am(BDPPM){sub 3}{sup 3+} complexes involved in the facilitated ion transfer reaction, were calculated to be 10{sup 23.9} and 10{sup 27.5}, respectively. On the basis of the results of CPEITIES, a feasibility of a new separation method, i.e., an electrolytic ion transfer separation, of actinide ions is evaluated. (author)

  19. Contribution to the study of uranyl salts in butyl phosphate solutions; Contribution a l'etude des solutions de sels d'uranyle dans les phosphates butyliques

    Energy Technology Data Exchange (ETDEWEB)

    Coulon, A. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    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 {approx} 1270 cm{sup -1} to {approx} 1180 cm{sup -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) [French] Une etude spectroscopique dans l'infrarouge moyen portant sur les associations: - phosphates trialcoyliques (tributylique - triethylique - trimethylique) - sels d'uranyle (nitrate, chlorure, acetate) a confirme l'existence d'une interaction entre le groupement phosphoryle et l'atome d'uranium, se manifestant par un deplacement de la bande d'absorption de la vibration de valence P = 0 de {approx} 1270 cm{sup -1} a {approx} 1180 cm{sup -1}. Une etude preparative, analytique et spectroscopique des solides obtenus par precipitation de sels d'uranyle par les phosphates butyliques acides a ete effectuee. La spectrophotomerie infrarouge met en evidence l'association, anterieure a toute introduction d'uranium, des phosphates tributylique et dibutylique dans des diluants non polaires. L'extraction de sels d'uranyle, d'une solution aqueuse acide par un melange dilue de phosphates tributylique et dibutylique, s'effectue suivant des processus differents a la

  20. Water at Interfaces.

    Science.gov (United States)

    Björneholm, Olle; Hansen, Martin H; Hodgson, Andrew; Liu, Li-Min; Limmer, David T; Michaelides, Angelos; Pedevilla, Philipp; Rossmeisl, Jan; Shen, Huaze; Tocci, Gabriele; Tyrode, Eric; Walz, Marie-Madeleine; Werner, Josephina; Bluhm, Hendrik

    2016-07-13

    The interfaces of neat water and aqueous solutions play a prominent role in many technological processes and in the environment. Examples of aqueous interfaces are ultrathin water films that cover most hydrophilic surfaces under ambient relative humidities, the liquid/solid interface which drives many electrochemical reactions, and the liquid/vapor interface, which governs the uptake and release of trace gases by the oceans and cloud droplets. In this article we review some of the recent experimental and theoretical advances in our knowledge of the properties of aqueous interfaces and discuss open questions and gaps in our understanding.

  1. 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.

  2. SALT4: a two-dimensional displacement discontinuity code for thermomechanical analysis in bedded salt deposits

    International Nuclear Information System (INIS)

    1983-04-01

    SALT4 is a two-dimensional analytical/displacement-discontinuity code designed to evaluate temperatures, deformation, and stresses associated with underground disposal of radioactive waste in bedded salt. This code was developed by the University of Minnesota. This documentation describes the mathematical equations of the physical system being modeled, the numerical techniques utilized, and the organization of the computer code, SALT4. The SALT4 code takes into account: (1) viscoelastic behavior in the pillars adjacent to excavations; (2) transversely isotropic elastic moduli such as those exhibited by bedded or stratified rock; and (2) excavation sequence. Major advantages of the SALT4 code are: (1) computational efficiency; (2) the small amount of input data required; and (3) a creep law consistent with laboratory experimental data for salt. The main disadvantage is that some of the assumptions in the formulation of SALT4, i.e., temperature-independent material properties, render it unsuitable for canister-scale analysis or analysis of lateral deformation of the pillars. The SALT4 code can be used for parameter sensitivity analyses of two-dimensional, repository-scale, thermal and thermomechanical response in bedded salt during the excavation, operational, and post-closure phases. It is especially useful in evaluating alternative patterns and sequences of excavation or waste canister placement. SALT4 can also be used to verify fully numerical codes. This is similar to the use of analytic solutions for code verification. Although SALT4 was designed for analysis of bedded salt, it is also applicable to crystalline rock if the creep calculation is suppressed. In Section 1.5 of this document the code custodianship and control is described along with the status of verification, validation and peer review of this report

  3. Salt Concentration Differences Alter Membrane Resistance in Reverse Electrodialysis Stacks

    KAUST Repository

    Geise, Geoffrey M.; Curtis, Andrew J.; Hatzell, Marta C.; Hickner, Michael A.; Logan, Bruce E.

    2014-01-01

    Membrane ionic resistance is usually measured by immersing the membrane in a salt solution at a single, fixed concentration. While salt concentration is known to affect membrane resistance when the same concentration is used on both sides

  4. Salts-based size-selective precipitation: toward mass precipitation of aqueous nanoparticles.

    Science.gov (United States)

    Wang, Chun-Lei; Fang, Min; Xu, Shu-Hong; Cui, Yi-Ping

    2010-01-19

    Purification is a necessary step before the application of nanocrystals (NCs), since the excess matter in nanoparticles solution usually causes a disadvantage to their subsequent coupling or assembling with other materials. In this work, a novel salts-based precipitation technique is originally developed for the precipitation and size-selective precipitation of aqueous NCs. Simply by addition of salts, NCs can be precipitated from the solution. After decantation of the supernatant solution, the precipitates can be dispersed in water again. By means of adjusting the addition amount of salt, size-selective precipitation of aqueous NCs can be achieved. Namely, the NCs with large size are precipitated preferentially, leaving small NCs in solution. Compared with the traditional nonsolvents-based precipitation technique, the current one is simpler and more rapid due to the avoidance of condensation and heating manipulations used in the traditional precipitation process. Moreover, the salts-based precipitation technique was generally available for the precipitation of aqueous nanoparticles, no matter if there were semiconductor NCs or metal nanoparticles. Simultaneously, the cost of the current method is also much lower than that of the traditional nonsolvents-based precipitation technique, making it applicable for mass purification of aqueous NCs.

  5. Fuel processing for molten-salt reactors

    International Nuclear Information System (INIS)

    Hightower, J.R. Jr.

    1976-01-01

    Research devoted to development of processes for the isolation of protactinium and for the removal of fission products from molten-salt breeder reactors is reported. During this report period, engineering development progressed on continuous fluorinators for uranium removal, the metal transfer process for rare-earth removal, the fuel reconstitution step, and molten salt--bismuth contactors to be used in reductive extraction processes. The metal transfer experiment MTE-3B was started. In this experiment all parts of the metal transfer process for rare-earth removal are demonstrated using salt flow rates which are about 1 percent of those required to process the fuel salt in a 1000-MW(e) MSBR. During this report period the salt and bismuth phases were transferred to the experimental vessels, and two runs with agitator speeds of 5 rps were made to measure the rate of transfer of neodymium from the fluoride salt to the Bi--Li stripper solution. The uranium removed from the fuel salt by fluorination must be returned to the processed salt in the fuel reconstitution step before the fuel salt is returned to the reactor. An engineering experiment to demonstrate the fuel reconstitution step is being installed. In this experiment gold-lined equipment will be used to avoid introducing products of corrosion by UF 6 and UF 5 . Alternative methods for providing the gold lining include electroplating and mechanical fabrication

  6. Decontaminated salt disposal as saltcrete in a landfill. Technical data summary

    International Nuclear Information System (INIS)

    1982-01-01

    This technical data summary presents a reference process for immobilizing decontaminated salt solution from the 200-Area waste storage tanks with cement, and disposing of the final waste material (called saltcrete) by burial in trenches. The saltcrete will be protected from leaching by clay and will be placed at least 3 meters above the historic high water table and beneath at least 5 meters of soil overburden. The decontaminated salt solution is a waste material which remains after the bulk of the radionuclides have been removed from waste tank supernate. This removal is effected by contacting the waste supernate with sodium tetraphenyl boron (Na-TPB) and sodium titanate (NaTi 2 O 5 H). These materials remove (by precipitation) most of the 137 Cs and 90 Sr as well as many other radioactive and non-radioactive elements. These precipitates, along with many other sludges which reside in the HLW tanks will be incorporated in borosilicate glass for eventual disposal in a geologic repository. An ion exchange process will also be used for removal of 99 Tc. The decontaminated salt solution has sufficiently low levels of radioactivity that it can be disposed of on-site. The scope of the curent effort is to describe a process for blending decontaminated salt solution with cement to form a saltcrete product which has dimensional stability and relatively low leachability. The process is to be capable of solidifying 10 gpm of supernate. About 100 million gallons of salt solution is to be solidified

  7. Attractive forces between hydrophobic solid surfaces measured by AFM on the first approach in salt solutions and in the presence of dissolved gases.

    Science.gov (United States)

    Azadi, Mehdi; Nguyen, Anh V; Yakubov, Gleb E

    2015-02-17

    Interfacial gas enrichment of dissolved gases (IGE) has been shown to cover hydrophobic solid surfaces in water. The atomic force microscopy (AFM) data has recently been supported by molecular dynamics simulation. It was demonstrated that IGE is responsible for the unexpected stability and large contact angle of gaseous nanobubbles at the hydrophobic solid-water interface. Here we provide further evidence of the significant effect of IGE on an attractive force between hydrophobic solid surfaces in water. The force in the presence of dissolved gas, i.e., in aerated and nonaerated NaCl solutions (up to 4 M), was measured by the AFM colloidal probe technique. The effect of nanobubble bridging on the attractive force was minimized or eliminated by measuring forces on the first approach of the AFM probe toward the flat hydrophobic surface and by using high salt concentrations to reduce gas solubility. Our results confirm the presence of three types of forces, two of which are long-range attractive forces of capillary bridging origin as caused by either surface nanobubbles or gap-induced cavitation. The third type is a short-range attractive force observed in the absence of interfacial nanobubbles that is attributed to the IGE in the form of a dense gas layer (DGL) at hydrophobic surfaces. Such a force was found to increase with increasing gas saturation and to decrease with decreasing gas solubility.

  8. A Fluorescence Recovery After Photobleaching (FRAP) Technique for the Measurement of Solute Transport Across Surfactant-Laden Interfaces

    Science.gov (United States)

    Browne, Edward P.; Hatton, T. Alan

    1996-01-01

    The technique of Fluorescence Recovery After Photobleaching (FRAP) has been applied to the measurement of interfacial transport in two-phase systems. FRAP exploits the loss of fluorescence exhibited by certain fluorophores when over-stimulated (photobleached), so that a two-phase system, originally at equilibrium, can be perturbed without disturbing the interface by strong light from an argon-ion laser and its recovery monitored by a microscope-mounted CCD camera as it relaxes to a new equilibrium. During this relaxation, the concentration profiles of the probe solute are measured on both sides of the interface as a function of time, yielding information about the transport characteristics of the system. To minimize the size of the meniscus between the two phases, a photolithography technique is used to selectively treat the glass walls of the cell in which the phases are contained. This allows concentration measurements to be made very close to the interface and increases the sensitivity of the FRAP technique.

  9. Attachment behavior of fission products to solution aerosol

    Energy Technology Data Exchange (ETDEWEB)

    Takamiya, Koichi; Tanaka, Toru; Nitta, Shinnosuke; Itosu, Satoshi; Sekimoto, Shun; Oki, Yuichi; Ohtsuki, Tsutomu [Research Reactor Institute, Kyoto University, Osaka (Japan)

    2016-12-15

    Various characteristics such as size distribution, chemical component and radioactivity have been analyzed for radioactive aerosols released from Fukushima Daiichi Nuclear Power Plant. Measured results for radioactive aerosols suggest that the potential transport medium for radioactive cesium was non-sea-salt sulfate. This result indicates that cesium isotopes would preferentially attach with sulfate compounds. In the present work the attachment behavior of fission products to aqueous solution aerosols of sodium salts has been studied using a generation system of solution aerosols and spontaneous fission source of {sup 248}Cm. Attachment ratios of fission products to the solution aerosols were compared among the aerosols generated by different solutions of sodium salt. A significant difference according as a solute of solution aerosols was found in the attachment behavior. The present results suggest the existence of chemical effects in the attachment behavior of fission products to solution aerosols.

  10. Mercury Phase II Study - Mercury Behavior in Salt Processing Flowsheet

    International Nuclear Information System (INIS)

    Jain, V.; Shah, H.; Wilmarth, W. R.

    2016-01-01

    Mercury (Hg) in the Savannah River Site Liquid Waste System (LWS) originated from decades of canyon processing where it was used as a catalyst for dissolving the aluminum cladding of reactor fuel. Approximately 60 metric tons of mercury is currently present throughout the LWS. Mercury has long been a consideration in the LWS, from both hazard and processing perspectives. In February 2015, a Mercury Program Team was established at the request of the Department of Energy to develop a comprehensive action plan for long-term management and removal of mercury. Evaluation was focused in two Phases. Phase I activities assessed the Liquid Waste inventory and chemical processing behavior using a system-by-system review methodology, and determined the speciation of the different mercury forms (Hg+, Hg++, elemental Hg, organomercury, and soluble versus insoluble mercury) within the LWS. Phase II activities are building on the Phase I activities, and results of the LWS flowsheet evaluations will be summarized in three reports: Mercury Behavior in the Salt Processing Flowsheet (i.e. this report); Mercury Behavior in the Defense Waste Processing Facility (DWPF) Flowsheet; and Mercury behavior in the Tank Farm Flowsheet (Evaporator Operations). The evaluation of the mercury behavior in the salt processing flowsheet indicates, inter alia, the following: (1) In the assembled Salt Batches 7, 8 and 9 in Tank 21, the total mercury is mostly soluble with methylmercury (MHg) contributing over 50% of the total mercury. Based on the analyses of samples from 2H Evaporator feed and drop tanks (Tanks 38/43), the source of MHg in Salt Batches 7, 8 and 9 can be attributed to the 2H evaporator concentrate used in assembling the salt batches. The 2H Evaporator is used to evaporate DWPF recycle water. (2) Comparison of data between Tank 21/49, Salt Solution Feed Tank (SSFT), Decontaminated Salt Solution Hold Tank (DSSHT), and Tank 50 samples suggests that the total mercury as well as speciated

  11. 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

  12. Waste salt recovery, recycle, and destruction

    International Nuclear Information System (INIS)

    Hickman, R.G.

    1992-12-01

    Starting in 1943 and continuing into the 1970s, radioactive wastes resulting from plutonium processing at Hanford were stored underground in 149 single shell tanks. Of these tanks, 66 are known or believedto be leaking, and over a period are believed to have leaked about 750,000 gal into the surrounding soil. The bulk of the aqueous solution has been removed and transferred to double shell tanks, none of which are leaking. The waste consists of 37 million gallons of salt cake and sludge. Most of the salt cake is sodium nitrate and other sodium salts. A substantial fraction of the sludge is sodium nitrate. Small amounts of the radionuclides are present in the sludge as oxides or hydroxides. In addition, some of the tanks contain organic compounds and ferrocyanide complexes, many of which have undergone radiolytic induced chemical changes during the years of storage. As part of the Hanford site remediation effort, the tank wastes must be removed, treated, and the residuals must be immobilized and disposed of in an environmentally acceptable manner. Removal methods of the waste from the tanks fall generally into three approaches: dry removal, slurry removal, and solution removed. The latter two methods are likely to result in some additional leakage to the surrounding soil, but that may be acceptable if the tank can be emptied and remediated before the leaked material permeates deeply into the soil. This effort includes three parts: salt splitting, acid separation, and destruction, with initial emphasis on salt splitting

  13. [Effect of shifting sand burial on evaporation reduction and salt restraint under saline water irrigation in extremely arid region].

    Science.gov (United States)

    Zhang, Jian-Guo; Zhao, Ying; Xu, Xin-Wen; Lei, Jia-Qiang; Li, Sheng-Yu; Wang, Yong-Dong

    2014-05-01

    The Taklimakan Desert Highway Shelterbelt is drip-irrigated with high saline groundwater (2.58-29.70 g x L(-1)), and shifting sand burial and water-salt stress are most common and serious problems in this region. So it is of great importance to study the effect of shifting sand burial on soil moisture evaporation, salt accumulation and their distribution for water saving, salinity restraint, and suitable utilization of local land and water resources. In this study, Micro-Lysimeters (MLS) were used to investigate dynamics of soil moisture and salt under different thicknesses of sand burial (1, 2, 3, 4, and 5 cm), and field control experiments of drip-irrigation were also carried out to investigate soil moisture and salt distribution under different thicknesses of shifting sand burial (5, 10, 15, 20, 25, 30, 35, and 40 cm). The soil daily and cumulative evaporation decreased with the increase of sand burial thickness in MLS, cumulative evaporation decreased by 2.5%-13.7% compared with control. And evaporative inhibiting efficiency increased with sand burial thickness, evaporative inhibiting efficiency of 1-5 cm sand burial was 16.7%-79.0%. Final soil moisture content beneath the interface of sand burial increased with sand burial thickness, and it increased by 2.5%-13.7% than control. The topsoil EC of shifting sand in MLS decreased by 1.19-6.00 mS x cm(-1) with the increasing sand burial thickness, whereas soil salt content beneath the interface in MLS increased and amplitude of the topsoil salt content was higher than that of the subsoil. Under drip-irrigation with saline groundwater, average soil moisture beneath the interface of shifting sand burial increased by 0.4% -2.0% compare with control, and the highest value of EC was 7.77 mS x cm(-1) when the sand burial thickness was 10 cm. The trend of salt accumulation content at shifting sand surface increased firstly, and then decreased with the increasing sand burial thickness. Soil salt contents beneath the

  14. Freshwater-Brine Mixing Zone Hydrodynamics in Salt Flats (Salar de Atacama)

    Science.gov (United States)

    Marazuela, M. A.; Vázquez-Suñé, E.; Custodio, E.; Palma, T.; García-Gil, A.

    2017-12-01

    The increase in the demand of strategic minerals for the development of medicines and batteries require detailed knowledge of the salt flats freshwater-brine interface to make its exploitation efficient. The interface zone is the result of a physical balance between the recharged and evaporated water. The sharp interface approach assumes the immiscibility of the fluids and thus neglects the mixing between them. As a consequence, for miscible fluids it is more accurate and often needed to use the mixing zone concept, which results from the dynamic equilibrium of flowing freshwater and brine. In this study, we consider two and three-dimensional scale approaches for the management of the mixing zone. The two-dimensional approach is used to understand the dynamics and the characteristics of the salt flat mixing zone, especially in the Salar de Atacama (Atacama salt flat) case. By making use of this model we analyze and quantify the effects of the aquitards on the mixing zone geometry. However, the understanding of the complex physical processes occurring in the salt flats and the management of these environments requires the adoption of three-dimensional regional scale numerical models. The models that take into account the effects of variable density represent the best management tool, but they require large computational resources, especially in the three-dimensional case. In order to avoid these computational limitations in the modeling of salt flats and their valuable ecosystems, we propose a three-step methodology, consisting of: (1) collection, validation and interpretation of the hydrogeochemical data, (2) identification and three-dimensional mapping of the mixing zone on the land surface and in depth, and (3) application of a water head correction to the freshwater and mixed water heads in order to compensate the density variations and to transform them to brine water heads. Finally, an evaluation of the sensibility of the mixing zone to anthropogenic and

  15. 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.

  16. Salt shell fallout during the ash eruption at the Nakadake crater, Aso volcano, Japan: evidence of an underground hydrothermal system surrounding the erupting vent

    Science.gov (United States)

    Shinohara, Hiroshi; Geshi, Nobuo; Yokoo, Akihiko; Ohkura, Takahiro; Terada, Akihiko

    2018-03-01

    A hot and acid crater lake is located in the Nakadake crater, Aso volcano, Japan. The volume of water in the lake decreases with increasing activity, drying out prior to the magmatic eruptions. Salt-rich materials of various shapes were observed, falling from the volcanic plume during the active periods. In May 2011, salt flakes fell from the gas plume emitted from an intense fumarole when the acid crater lake was almost dry. The chemical composition of these salt flakes was similar to those of the salts formed by the drying of the crater lake waters, suggesting that they originated from the crater lake water. The salt flakes are likely formed by the drying up of the crater lake water droplets sprayed into the plume by the fumarolic gas jet. In late 2014, the crater lake dried completely, followed by the magmatic eruptions with continuous ash eruptions and intermittent Strombolian explosions. Spherical hollow salt shells were observed on several occasions during and shortly after the weak ash eruptions. The chemical composition of the salt shells was similar to the salts formed by the drying of the crater lake water. The hollow structure of the shells suggests that they were formed by the heating of hydrothermal solution droplets suspended by a mixed stream of gas and ash in the plume. The salt shells suggest the existence of a hydrothermal system beneath the crater floor, even during the course of magmatic eruptions. Instability of the magmatic-hydrothermal interface can cause phreatomagmatic explosions, which often occur at the end of the eruptive phase of this volcano.

  17. Salts of alkali metal anions and process of preparing same

    Science.gov (United States)

    Dye, James L.; Ceraso, Joseph M.; Tehan, Frederick J.; Lok, Mei Tak

    1978-01-01

    Compounds of alkali metal anion salts of alkali metal cations in bicyclic polyoxadiamines are disclosed. The salts are prepared by contacting an excess of alkali metal with an alkali metal dissolving solution consisting of a bicyclic polyoxadiamine in a suitable solvent, and recovered by precipitation. The salts have a gold-color crystalline appearance and are stable in a vacuum at -10.degree. C. and below.

  18. Hoffmeister Series Ions Protect Diphtheria Toxoid from Structural Damages at Solvent/Water Interface

    Directory of Open Access Journals (Sweden)

    Pedro S. de Araujo

    2009-07-01

    Full Text Available During the W1/O phase (in the W1/O/W2 process of protein microencapsulation within poly-lactide-co-glycolide (PLGA, hydrophobic interfaces are expanded where interfacial adsorption occurs followed by protein unfolding and aggregation. Spectroscopic and immunological techniques were used to ascertain the effects of the Hoffmeister series ions on Diphtheria toxoid (Dtxd stability during the W1/O phase. A correlation was established between salts used in aqueous solutions and the changes in Dtxd solubility and conformation. The Dtxd α-helical content was quite stable thus leading to the conclusion that encapsulation was followed by protein aggregation, with minor exposition of hydrophobic residues and a small change at the S-S dihedral angle. Dtxd aggregation is 95% avoided by the chaotropic SCN-. This was used to prepare a stable Dtxd and immunologically recognized/PLGA formulation in the presence of 30 mM SNC-. The recovery increased by 10.42% or 23.2% when microencapsulation was within the -COOMe or -COOH (12kDa PLGA, respectively. In conclusion, the aim of this work was achieved, which was to obtain the maximum of Dtxd stability after contact with CH2Cl2 to begin its PLGA microencapsulation within ideal conditions. This was a technological breakthrough because a simple solution like salt addition avoided heterologous proteins usage.

  19. Magnesium and iron nanoparticles production using microorganisms and various salts

    Science.gov (United States)

    Kaul, R. K.; Kumar, P.; Burman, U.; Joshi, P.; Agrawal, A.; Raliya, R.; Tarafdar, J. C.

    2012-09-01

    Response of five fungi and two bacteria to different salts of magnesium and iron for production of nanoparticles was studied. Pochonia chlamydosporium, and Aspergillus fumigatus were exposed to three salts of magnesium while Curvularia lunata, Chaetomium globosum, A. fumigatus, A. wentii and the bacteria Alcaligenes faecalis and Bacillus coagulans were exposed to two salts of iron for nanoparticle production. The results revealed that P. chlamydosporium induces development of extracellular nanoparticles in MgCl2 solution while A. fumigatus produces also intracellular nanoparticles when exposed to MgSO4 solution. C. globosum was found as the most effective in producing nanoparticles when exposed to Fe2O3 solution. The FTIR analysis of the nanoparticles obtained from Fe2O3 solution showed the peaks similar to iron (Fe). In general, the species of the tested microbes were selective to different chemicals in their response for synthesis of nanoparticles. Further studies on their characterization and improving the efficiency of promising species of fungi need to be undertaken before tapping their potential as nanonutrients for plants.

  20. 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.

  1. Ion transport mechanisms in lamellar phases of salt-doped PS–PEO block copolymer electrolytes

    KAUST Repository

    Sethuraman, Vaidyanathan; Mogurampelly, Santosh; Ganesan, Venkat

    2017-01-01

    We use a multiscale simulation strategy to elucidate, at an atomistic level, the mechanisms underlying ion transport in the lamellar phase of polystyrene–polyethylene oxide (PS–PEO) block copolymer (BCP) electrolytes doped with LiPF6 salts. Explicitly, we compare the results obtained for ion transport in the microphase separated block copolymer melts to those for salt-doped PEO homopolymer melts. In addition, we also present results for dynamics of the ions individually in the PEO and PS domains of the BCP melt, and locally as a function of the distance from the lamellar interfaces. When compared to the PEO homopolymer melt, ions were found to exhibit slower dynamics in both the block copolymer (overall) and in the PEO phase of the BCP melt. Such results are shown to arise from the effects of slower polymer segmental dynamics in the BCP melt and the coordination characteristics of the ions. Polymer backbone-ion residence times analyzed as a function of distance from the interface indicate that ions have a larger residence time near the interface compared to that near the bulk of lamella, and demonstrates the influence of the glassy PS blocks and microphase segregation on the ion transport properties. Ion transport mechanisms in BCP melts reveal that there exist five distinct mechanisms for ion transport along the backbone of the chain and exhibit qualitative differences from the behavior in homopolymer melts. We also present results as a function of salt concentration which show that the mean-squared displacements of the ions decrease with increasing salt concentration, and that the ion residence times near the polymer backbone increase with increasing salt concentration.

  2. Ion transport mechanisms in lamellar phases of salt-doped PS–PEO block copolymer electrolytes

    KAUST Repository

    Sethuraman, Vaidyanathan

    2017-10-23

    We use a multiscale simulation strategy to elucidate, at an atomistic level, the mechanisms underlying ion transport in the lamellar phase of polystyrene–polyethylene oxide (PS–PEO) block copolymer (BCP) electrolytes doped with LiPF6 salts. Explicitly, we compare the results obtained for ion transport in the microphase separated block copolymer melts to those for salt-doped PEO homopolymer melts. In addition, we also present results for dynamics of the ions individually in the PEO and PS domains of the BCP melt, and locally as a function of the distance from the lamellar interfaces. When compared to the PEO homopolymer melt, ions were found to exhibit slower dynamics in both the block copolymer (overall) and in the PEO phase of the BCP melt. Such results are shown to arise from the effects of slower polymer segmental dynamics in the BCP melt and the coordination characteristics of the ions. Polymer backbone-ion residence times analyzed as a function of distance from the interface indicate that ions have a larger residence time near the interface compared to that near the bulk of lamella, and demonstrates the influence of the glassy PS blocks and microphase segregation on the ion transport properties. Ion transport mechanisms in BCP melts reveal that there exist five distinct mechanisms for ion transport along the backbone of the chain and exhibit qualitative differences from the behavior in homopolymer melts. We also present results as a function of salt concentration which show that the mean-squared displacements of the ions decrease with increasing salt concentration, and that the ion residence times near the polymer backbone increase with increasing salt concentration.

  3. 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.

  4. Molecular dynamics simulations of the calcite/solution interface as a means to explore surface modifications induced by nitrate

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, Sascha; Schmidt, Moritz [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Div. Surface Processes; Spijker, P. [Aalto Univ., Helsinki (Finland). Dept. of Applied Physics; Voitchovsky, K. [Durham Univ. (United Kingdom). Physics Dept.

    2016-07-01

    The reactivity of calcite, one of the most abundant minerals in the earth's crust, is determined by the molecular details of its interface with the contacting solution. Recently, it has been found that trace concentrations of NaNO{sub 3} severely affect calcite's (104) surface and its reactivity. Molecular dynamics (MD) simulations reveal density profiles of different ions near calcite's surface, with NO{sub 3}{sup -} able to reach closer to the surface than CO{sub 3}{sup 2-} and in higher concentrations. Additionally, incorporation of NO{sub 3}{sup -} into the surface significantly disturbs the water structure at the interface.

  5. Brine flow in heated geologic salt.

    Energy Technology Data Exchange (ETDEWEB)

    Kuhlman, Kristopher L.; Malama, Bwalya

    2013-03-01

    This report is a summary of the physical processes, primary governing equations, solution approaches, and historic testing related to brine migration in geologic salt. Although most information presented in this report is not new, we synthesize a large amount of material scattered across dozens of laboratory reports, journal papers, conference proceedings, and textbooks. We present a mathematical description of the governing brine flow mechanisms in geologic salt. We outline the general coupled thermal, multi-phase hydrologic, and mechanical processes. We derive these processes governing equations, which can be used to predict brine flow. These equations are valid under a wide variety of conditions applicable to radioactive waste disposal in rooms and boreholes excavated into geologic salt.

  6. The blanket interface to TSTA

    International Nuclear Information System (INIS)

    Clemmer, R.G.; Finn, P.A.; Grimm, T.L.; Sze, D.K.; Anderson, J.L.; Bartlit, J.R.; Naruse, Y.; Yoshida, H.

    1988-01-01

    The requirements of tritium technology are centered in three main areas, (1) fuel processing, (2) breeder tritium extraction, and (3) tritium containment. The Tritium Systems Test Assembly (TSTA) now in operation at Los Alamos National Laboratory (LANL) is dedicated to developing and demonstrating the tritium technology for fuel processing and containment. TSTA is the only fusion fuel processing facility that can operate in a continuous closed-loop mode. The tritium throughput of TSTA is 1000 g/d. However, TSTA does not have a blanket interface system. The authors have initiated a study to define a Breeder Blanket Interface (BBIO) for TSTA. The first step of the work is to define the condition of the gaseous tritium stream from the blanket tritium recovery system. This report summarizes this part of the work for one particular blanket concept, i.e., a self-cooled lithium blanket. The total gas throughput, the hydrogen to tritium ratio, the corrosive chemicals, and the radionuclides are defined. Various methods of tritium recovery from liquid lithium were assessed: yttrium gettering, permeation windows, and molten salt extraction. The authors' evaluation concluded that the best method was molten salt extraction

  7. Thermal interface material characterization for cryogenic electronic packaging solutions

    Science.gov (United States)

    Dillon, A.; McCusker, K.; Van Dyke, J.; Isler, B.; Christiansen, M.

    2017-12-01

    As applications of superconducting logic technologies continue to grow, the need for efficient and reliable cryogenic packaging becomes crucial to development and testing. A trade study of materials was done to develop a practical understanding of the properties of interface materials around 4 K. While literature exists for varying interface tests, discrepancies are found in the reported performance of different materials and in the ranges of applied force in which they are optimal. In considering applications extending from top cooling a silicon chip to clamping a heat sink, a range of forces from approximately 44 N to approximately 445 N was chosen for testing different interface materials. For each range of forces a single material was identified to optimize the thermal conductance of the joint. Of the tested interfaces, indium foil clamped at approximately 445 N showed the highest thermal conductance. Results are presented from these characterizations and useful methodologies for efficient testing are defined.

  8. 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.

  9. 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...

  10. Small angle neutron scattering study of polyelectrolyte brushes grafted to well-defined gold nanoparticle interfaces.

    Science.gov (United States)

    Jia, Haidong; Grillo, Isabelle; Titmuss, Simon

    2010-05-18

    Small angle neutron scattering (SANS) has been used to study the conformations, and response to added salt, of a polyelectrolyte layer grafted to the interfaces of well-defined gold nanoparticles. The polyelectrolyte layer is prepared at a constant coverage by grafting thiol-functionalized polystyrene (M(w) = 53k) to gold nanoparticles of well-defined interfacial curvature (R(c) = 26.5 nm) followed by a soft-sulfonation of 38% of the segments to sodium polystyrene sulfonate (NaPSS). The SANS profiles can be fit by Fermi-Dirac distributions that are consistent with a Gaussian distribution but are better described by a parabolic distribution plus an exponential tail, particularly in the high salt regime. These distributions are consistent with the predictions and measurements for osmotic and salted brushes at interfaces of low curvature. When the concentration of added salt exceeds the concentration of counterions inside the brush, there is a salt-induced deswelling, but even at the highest salt concentration the brush remains significantly swollen due to a short-ranged excluded volume interaction. This is responsible for the observed resistance to aggregation of these comparatively high concentration polyelectrolyte stabilized gold nanoparticle dispersions even in the presence of a high concentration of added salt.

  11. Evaluation of layered zinc hydroxide nitrate and zinc/nickel double hydroxide salts in the removal of chromate ions from solutions

    International Nuclear Information System (INIS)

    Bortolaz de Oliveira, Henrique; Wypych, Fernando

    2016-01-01

    Layered zinc hydroxide nitrate (ZnHN) and Zn/Ni layered double hydroxide salts were synthesized and used to remove chromate ions from solutions at pH 8.0. The materials were characterized by many instrumental techniques before and after chromate ion removal. ZnHN decomposed after contact with the chromate solution, whereas the layered structure of Zn/Ni hydroxide nitrate (Zn/NiHN) and Zn/Ni hydroxide acetate (Zn/NiHA) remained their layers intact after the topotactic anionic exchange reaction, only changing the basal distances. ZnHN, Zn/NiHN, and Zn/NiHA removed 210.1, 144.8, and 170.1 mg of CrO 4 2− /g of material, respectively. Although the removal values obtained for Zn/NiHN and Zn/NiHA were smaller than the values predicted for the ideal formulas of the solids (194.3 and 192.4 mg of CrO 4 2− /g of material, respectively), the measured capacities were higher than the values achieved with many materials reported in the literature. Kinetic experiments showed the removal reaction was fast. To facilitate the solid/liquid separation process after chromium removal, Zn/Ni layered double hydroxide salts with magnetic supports were also synthesized, and their ability to remove chromate was evaluated. - Highlights: • Zinc hydroxide nitrate and Zn/Ni hydroxide nitrate or acetate were synthesized. • The interlayer anions were replaced by chromate anions at pH=8.0. • Only Zn/Ni hydroxide nitrate or acetate have the structure preserved after exchange. • Fast exchange reaction and high capacity of chromate removal were observed. • Magnetic materials were obtained to facilitate the solids removal the from solutions.

  12. Sealing of boreholes using natural, compatible materials: Granular salt

    International Nuclear Information System (INIS)

    Finley, R.E.; Zeuch, D.H.; Stormont, J.C.; Daemen, J.J.K.

    1994-01-01

    Granular salt can be used to construct high performance permanent seals in boreholes which penetrate rock salt formations. These seals are described as seal systems comprised of the host rock, the seal material, and the seal rock interface. The performance of these seal systems is defined by the complex interactions between these seal system components through time. The interactions are largely driven by the creep of the host formation applying boundary stress on the seal forcing host rock permeability with time. The immediate permeability of these seals is dependent on the emplaced density. Laboratory test results suggest that careful emplacement techniques could results in immediate seal system permeability on the order of 10 -16 m 2 to 10 -18 m 2 (10 -4 darcy to 10 -6 ). The visco-plastic behavior of the host rock coupled with the granular salts ability to ''heal'' or consolidate make granular salt an ideal sealing material for boreholes whose permanent sealing is required

  13. Expected environment for waste packages in a salt repository

    International Nuclear Information System (INIS)

    Pederson, L.R.; Clark, D.E.; Hodges, F.N.; McVay, G.L.; Rai, D.

    1983-01-01

    This paper discusses results of recent efforts to define the very near-field (within approximately 2 m) environmental conditions to which waste packages will be exposed in a salt repository. These conditions must be considered in the experimental design for waste package materials testing, which includes corrosion of barrier materials and leaching of waste forms. Site-specific brine compositions have been determined, and standard brine compositions have been selected for testing purposes. Actual brine compositions will vary depending on origin, temperature, irradiation history, and contact with irradiated rock salt. Results of irradiating rock salt, synthetic brines, rock salt/brine mixtures, and reactions of irradiated rock salt with brine solutions are reported. 38 references, 3 figures, 2 tables

  14. Optimization of Fluorescent Silicon Nano material Production Using Peroxide/ Acid/ Salt Technique

    International Nuclear Information System (INIS)

    Abuhassan, L.H.

    2009-01-01

    Silicon nano material was prepared using the peroxide/ acid/ salt technique in which an aqueous silicon-based salt solution was added to H 2 O 2 / HF etchants. In order to optimize the experimental conditions for silicon nano material production, the amount of nano material produced was studied as a function of the volume of the silicon salt solution used in the synthesis. A set of samples was prepared using: 0, 5, 10, 15, and 20 ml of an aqueous 1 mg/ L metasilicate solution. The area under the corresponding peaks in the infrared (ir) absorption spectra was used as a qualitative indicator to the amount of the nano material present. The results indicated that using 10 ml of the metasilicate solution produced the highest amount of nano material. Furthermore, the results demonstrated that the peroxide/ acid/ salt technique results in the enhancement of the production yield of silicon nano material at a reduced power demand and with a higher material to void ratio. A model in which the silicon salt forms a secondary source of silicon nano material is proposed. The auxiliary nano material is deposited into the porous network causing an increase in the amount of nano material produced and a reduction in the voids present. Thus a reduction in the resistance of the porous layer, and consequently reduction in the power required, are expected. (author)

  15. Sulfomethylated lignite salt as a sacrifical agent in oil recovery processes

    Energy Technology Data Exchange (ETDEWEB)

    Kudchadker, M.V.; Weiss, W.J.

    1978-02-07

    A process is described for recovering petroleum from oil reservoirs by secondary recovery methods. The process involves injecting via an injection well into the reservoir an aqueous solution of sulfomethylated lignite salt as a sacrificial agent to inhibit the deposition of surfactant and polymer on the reservoir matrix. The process is conducted by first injecting the lignite salt into the formation through the injection well and following it with either a polymer or a surfactant solution, which also may contain the lignite salt. The polymer or surfactant would then be followed by a drive fluid, such as water, to push the chemicals and oil to the production well. (18 claims)

  16. Sol-gel processing with inorganic metal salt precursors

    Science.gov (United States)

    Hu, Zhong-Cheng

    2004-10-19

    Methods for sol-gel processing that generally involve mixing together an inorganic metal salt, water, and a water miscible alcohol or other organic solvent, at room temperature with a macromolecular dispersant material, such as hydroxypropyl cellulose (HPC) added. The resulting homogenous solution is incubated at a desired temperature and time to result in a desired product. The methods enable production of high quality sols and gels at lower temperatures than standard methods. The methods enable production of nanosize sols from inorganic metal salts. The methods offer sol-gel processing from inorganic metal salts.

  17. Borehole closure in salt

    International Nuclear Information System (INIS)

    Fuenkajorn, K.; Daemen, J.J.K.

    1988-12-01

    Constitutive law parameters are determined from salt behavior characterization experiments. The results are applied to predict creep (time-dependent) closure of boreholes in salt specimens subjected to various loading configurations. Rheological models (linear and nonlinear viscoelastic and viscoplastic models), empirical models, and physical theory models have been formulated from the results of uniaxial creep tests, strain and stress rate controlled uniaxial tests, constant strain rate triaxial tests, cyclic loading tests, and seismic velocity measurements. Analytical solutions for a thick-walled cylinder subjected to internal and external pressures and for a circular hole in an infinite plate subjected to a biaxial or uniaxial stressfield have been derived from each of the linear viscoelastic models and from one of the empirical laws. The experimental results indicate that the salt samples behave as an elastic-viscoplastic material. The elastic behavior tends to be linear and time-independent. The plastic deformation is time-dependent. The stress increment to strain rate increment ratio gradually decreases as the stress level increases. The transient potential creep law seems to give the simplest satisfactory governing equation describing the viscoplastic behavior of salt during the transient phase. 204 refs., 27 figs., 29 tabs

  18. Molten salt reactor concept

    International Nuclear Information System (INIS)

    Sood, D.D.

    1980-01-01

    Molten salt reactor is an advanced breeder concept which is suited for the utilization of thorium for nuclear power production. This reactor is based on the use of solutions of uranium or plutonium fluorides in LiF-BeF 2 -ThF 4 as fuel. Unlike the conventional reactors, no external coolant is used in the reactor core and the fuel salt itself is circulated through heat exchangers to transfer the fission produced heat to a secondary salt (NaF-NaBF 4 ) for steam generation. A part of the fuel stream is continuously processed to isolate 233 Pa, so that it can decay to fissile 233 U without getting converted to 234 Pa, and for the removal of neutron absorbing fission products. This on-line processing scheme makes this reactor concept to achieve a breeding ratio of 1.07 which is the highest for any thermal breeder reactor. Experimental studies at the Bhabha Atomic Research Centre, Bombay, have established the use of plutonium as fuel for this reactor. This molten salt reactor concept is described and the work conducted at the Bhabha Atomic Research Centre is summarised. (auth.)

  19. 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.

  20. Charge regulation at semiconductor-electrolyte interfaces.

    Science.gov (United States)

    Fleharty, Mark E; van Swol, Frank; Petsev, Dimiter N

    2015-07-01

    The interface between a semiconductor material and an electrolyte solution has interesting and complex electrostatic properties. Its behavior will depend on the density of mobile charge carriers that are present in both phases as well as on the surface chemistry at the interface through local charge regulation. The latter is driven by chemical equilibria involving the immobile surface groups and the potential determining ions in the electrolyte solution. All these lead to an electrostatic potential distribution that propagate such that the electrolyte and the semiconductor are dependent on each other. Hence, any variation in the charge density in one phase will lead to a response in the other. This has significant implications on the physical properties of single semiconductor-electrolyte interfaces and on the electrostatic interactions between semiconductor particles suspended in electrolyte solutions. The present paper expands on our previous publication (Fleharty et al., 2014) and offers new results on the electrostatics of single semiconductor interfaces as well as on the interaction of charged semiconductor colloids suspended in electrolyte solution. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. 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.

  2. 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.

  3. A Kinetic Model for β-Amyloid Adsorption at the Air/Solution Interface and Its Implication to the β-Amyloid Aggregation Process

    Science.gov (United States)

    Jiang, Dianlu; Dinh, Kim Lien; Ruthenburg, Travis; Zhang, Yi; Su, Lei; Land, Donald; Zhou, Feimeng

    2011-01-01

    The kinetics of adsorption at the air/buffer solution interface of amyloid beta peptide, Aβ(1–42), whose bulk concentration (submicromolar) is more than two orders of magnitude lower than that typically used in other in vitro aggregation studies, has been studied using a Langmuir-Blodgett trough. The pressure–time curves exhibit a lag phase, wherein the surface pressure essentially remains at zero, and a rising phase, corresponding to the Aβ adsorption at the interface. The duration of the lag phase was found to be highly dependent on both the Aβ bulk concentration and the solution temperature. A large activation energy (62.2 ± 4.1 KJ/mol) was determined and the apparent adsorption rate constant was found to be linearly dependent on the Aβ bulk concentration. Attenuated total reflection-IR spectra of the adsorbed Aβ transferred to a solid substrate and circular dichroism measurements of Aβ in the solution layer near the interface reveal that the natively unstructured Aβ in the bulk undergo a conformation change (folding) to mainly the α-helical structure. The results suggest that, prior to the adsorption step, an equilibrium between Aβ conformations is established within the subsurface. The kinetic equation derived from this model confirms that the overall Aβ adsorption is kinetically controlled and the apparent rate constant is proportional to the Aβ bulk concentration. This model also indicates that interfaces such as cell membranes and lipid bilayers may facilitate Aβ aggregation/fibrillation by providing a thin hydrophobic layer adjacent to the interface for the initial Aβ conformation change (misfolding) and accumulation. Such a preconcentration effect offers a plausible explanation of the fact that Aβ fibrillation occurs in vivo at nanomolar concentrations. Another important biological implication from our work is that Aβ misfolding may occur before its adsorption onto a cell membrane. This general kinetic model should also find

  4. A kinetic model for beta-amyloid adsorption at the air/solution interface and its implication to the beta-amyloid aggregation process.

    Science.gov (United States)

    Jiang, Dianlu; Dinh, Kim Lien; Ruthenburg, Travis C; Zhang, Yi; Su, Lei; Land, Donald P; Zhou, Feimeng

    2009-03-12

    At the air/buffer solution interface the kinetics of adsorption of amyloid beta peptide, Abeta(1-42), whose bulk concentration (submicromolar) is more than 2 orders of magnitude lower than that typically used in other in vitro aggregation studies, has been studied using a Langmuir-Blodgett trough. The pressure-time curves exhibit a lag phase, wherein the surface pressure essentially remains at zero, and a rising phase, corresponding to the Abeta adsorption at the interface. The duration of the lag phase was found to be highly dependent on both the Abeta bulk concentration and the solution temperature. A large activation energy (62.2 +/- 4.1 KJ/mol) was determined and the apparent adsorption rate constant was found to be linearly dependent on the Abeta bulk concentration. Attenuated total reflection-IR spectra of the adsorbed Abeta transferred to a solid substrate and circular dichroism measurements of Abeta in the solution layer near the interface reveal that the natively unstructured Abeta in the bulk undergo a conformation change (folding) to mainly the alpha-helical structure. The results suggest that, prior to the adsorption step, an equilibrium between Abeta conformations is established within the subsurface. The kinetic equation derived from this model confirms that the overall Abeta adsorption is kinetically controlled and the apparent rate constant is proportional to the Abeta bulk concentration. This model also indicates that interfaces such as cell membranes and lipid bilayers may facilitate Abeta aggregation/ fibrillation by providing a thin hydrophobic layer adjacent to the interface for the initial A/beta conformation change (misfolding) and accumulation. Such a preconcentration effect offers a plausible explanation of the fact that Abeta fibrillation occurs in vivo at nanomolar concentrations. Another important biological implication from our work is that Abeta misfolding may occur before its adsorption onto a cell membrane. This general kinetic model

  5. Scorpion toxins prefer salt solutions

    Czech Academy of Sciences Publication Activity Database

    Nikouee, A.; Khabiri, Morteza; Cwiklik, Lukasz

    2015-01-01

    Roč. 21, č. 11 (2015), 287/1-287/14 ISSN 1610-2940 R&D Projects: GA ČR GA13-06181S Institutional support: RVO:61388963 ; RVO:61388955 Keywords : ionic solutions * molecular dynamics * nonaqueous media * secondary structure Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.438, year: 2015

  6. Theoretical and experimental studies of reverse osmosis separation of inorganic salts in aqueous solutions; Estudio teorico y experimental de parametros de transporte a traves de membranas de osmosis inversa : Efecto de varios tipos de sales

    Energy Technology Data Exchange (ETDEWEB)

    Khavet, M.; Mengual, J. I.

    2004-07-01

    Theoretical and experimental studies of reverse osmosis separation of inorganic salts in aqueous solutions have been carried out. In this study, a polyamide thin film composite membrane in spiral wound configuration was used. The free energy of different inorganic monovalent (LiCl, NaCl, KCl, NaBr, NaI, LiBr, KBr) and divalent (MgCl2, MnCl2, CaCl2, MgBr2) salts has been calculated. The solute transport parameters were related to the free energy of the corresponding cations and anions. The mass transfer coefficient at the high pressure feed side of the spiral wound module was determined for each type of salt. The obtained theoretical values were compared to the experimental ones. The good agreements observed between the experimental and theoretical results confirm the validity of the theoretical procedure, which may be applied in modelling solar reverse osmosis plants for the prediction of the separation factor of various types of inorganic salts. (Author)

  7. Mass transfer and transport in salt repositories

    International Nuclear Information System (INIS)

    Pigford, T.H.; Chambre, P.L.; Lee, W.W.L.

    1989-02-01

    Salt is a unique rock isolation of nuclear waste because it is ''dry'' and nearly impermeable. In this paper we summarize some mass-transfer and transport analyses of salt repositories. First we analyses brine migration. Heating by high-level waste can cause brine in grain boundaries to move due to pressure-gradients. We analyze brine migration treating salt as a thermoelastic solid and found that brine migration is transient and localized. We use previously developed techniques to estimate release rates from waste packages by diffusion. Interbeds exist in salt and may be conduits for radionuclide migration. We analyze steady-state migration due to brine flow in the interbed, as a function of the Peclet number. Then we analyze transient mass transfer, both into the interbed and directly to salt, due only to diffusion. Finally we compare mass transfer rates of a waste cylinder in granite facing a fracture and in salt facing an interbed. In all cases, numerical illustrations of the analytic solution are given. 10 refs., 4 figs., 3 tabs

  8. 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)

  9. Salt stabilizer for preventing chlorine depletion and increasing shelf-life of potable water - A concept

    Science.gov (United States)

    Copeland, E. J.; Edgerley, R. H.

    1971-01-01

    Proposed concept, based on law of mass action uses addition of salt to increase chlorine ions produced in sodium hydrochlorite solutions, thereby increasing solution shelf-life. This technique is not costly. Usefulness will be determined by acceptability of salt in product undergoing long shelf-life.

  10. Molten salt reactor type

    International Nuclear Information System (INIS)

    1977-01-01

    This document is one of the three parts of a first volume devoted to the compilations of American data on the molten salt reactor concept. This part 'CIRCUITS' regroups under a condensed form - in French and using international units - the essential information contained in both basic documents of the American project for a molten-salt breeder power plant. This part is only dealing with things relating to the CEA-EDF workshop 'CIRCUITS'. It is not concerned with information on: the reactor and the moderator replacement, the primary and secondary salts, and the fuel salt reprocessing, that are dealt with in parts 'CORE' and 'CHEMISTRY' respectively. The possible evolutions in the data - and solutions - taken by the American designers for their successive projects (1970 to 1972) are shown. The MSBR power plant comprises three successive heat transfer circuits. The primary circuit (Hastelloy N), radioactive and polluted, containing the fuel salt, includes the reactor, pumps and exchangers. The secondary circuit (pipings made of modified Hastelloy N) contaminated in the exchanger, ensures the separation between the fuel and the fluid operating the turbo-alternator. The water-steam circuit feeds the turbine with steam. This steam is produced in the steam generator flowed by the secondary fluid. Some subsidiary circuits (discharge and storage of the primary and secondary salts, ventilation of the primary circuit ...) complete the three principal circuits which are briefly described. All circuits are enclosed inside the controlled-atmosphere building of the nuclear boiler. This building also ensures the biological protection and the mechanical protection against outer aggressions [fr

  11. Standard Gibbs free energies for transfer of actinyl ions at the aqueous/organic solution interface

    International Nuclear Information System (INIS)

    Kitatsuji, Yoshihiro; Okugaki, Tomohiko; Kasuno, Megumi; Kubota, Hiroki; Maeda, Kohji; Kimura, Takaumi; Yoshida, Zenko; Kihara, Sorin

    2011-01-01

    Research highlights: → Standard Gibbs free energies for ion-transfer of tri- to hexavalent actinide ions. → Determination is based on distribution method combined with ion-transfer voltammetry. → Organic solvents examined are nitrobenzene, DCE, benzonitrile, acetophenone and NPOE. → Gibbs free energies of U(VI), Np(VI) and Pu(VI) are similar to each other. → Gibbs free energies of Np(V) is very large, comparing with ordinary monovalent cations. - Abstract: Standard Gibbs free energies for transfer (ΔG tr 0 ) of actinyl ions (AnO 2 z+ ; z = 2 or 1; An: U, Np, or Pu) between an aqueous solution and an organic solution were determined based on distribution method combined with voltammetry for ion transfer at the interface of two immiscible electrolyte solutions. The organic solutions examined were nitrobenzene, 1,2-dichloroethane, benzonitrile, acetophenone, and 2-nitrophenyl octyl ether. Irrespective of the type of organic solutions, ΔG tr 0 of UO 2 2+ ,NpO 2 2+ , and PuO 2 2+ were nearly equal to each other and slightly larger than that of Mg 2+ . The ΔG tr 0 of NpO 2 + was extraordinary large compared with those of ordinary monovalent cations. The dependence of ΔG tr 0 of AnO 2 z+ on the type of organic solutions was similar to that of H + or Mg 2+ . The ΔG tr 0 of An 3+ and An 4+ were also discussed briefly.

  12. 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

  13. Thermodynamic modeling of iodine and selenium retention in solutions with high salinity

    International Nuclear Information System (INIS)

    Hagemann, Sven; Moog, Helge C.; Herbert, Horst-Juergen; Erich, Agathe

    2012-04-01

    The report on iodine and selenium retention in saline solutions includes the following chapters: (1) Introduction and scope of the work. (2) Actual status of knowledge. (3) Experimental and numerical models. (4) Thermodynamic properties of selenite and hydrogen selenite in solutions of oceanic salts. (5) Thermodynamic properties of selenate in solutions of oceanic salts. (6) Thermodynamic properties of iodide in solutions of oceanic salts. (7) Experimental studies on the retention of iodine and selenium in selected sorbents. (8) Summary and conclusions.

  14. Exploration of polyelectrolytes as draw solutes in forward osmosis processes

    KAUST Repository

    Ge, Qingchun

    2012-03-01

    The development of the forward osmosis (FO) process has been constrained by the slow development of appropriate draw solutions. Two significant concerns related to draw solutions are the draw solute leakage and intensiveenergy requirement in recycling draw solutes after the FO process. FO would be much attractive if there is no draw solute leakage and the recycle of draw solutes is easy and economic. In this study, polyelectrolytes of a series of polyacrylic acid sodium salts (PAA-Na), were explored as draw solutes in the FO process. The characteristics of high solubility in water and flexibility in structural configuration ensure the suitability of PAA-Na as draw solutes and their relative ease in recycle through pressure-driven membrane processes. The high water flux with insignificant salt leakage in the FO process and the high salt rejection in recycle processes reveal the superiority of PAA-Na to conventional ionic salts, such as NaCl, when comparing their FO performance via the same membranes. The repeatable performance of PAA-Na after recycle indicates the absence of any aggregation problems. The overall performance demonstrates that polyelectrolytes of PAA-Na series are promising as draw solutes, and the new concept of using polyelectrolytes as draw solutes in FO processes is applicable. © 2011 Elsevier Ltd.

  15. Proteins in solution: Fractal surfaces in solutions

    Directory of Open Access Journals (Sweden)

    R. Tscheliessnig

    2016-02-01

    Full Text Available The concept of the surface of a protein in solution, as well of the interface between protein and 'bulk solution', is introduced. The experimental technique of small angle X-ray and neutron scattering is introduced and described briefly. Molecular dynamics simulation, as an appropriate computational tool for studying the hydration shell of proteins, is also discussed. The concept of protein surfaces with fractal dimensions is elaborated. We finish by exposing an experimental (using small angle X-ray scattering and a computer simulation case study, which are meant as demonstrations of the possibilities we have at hand for investigating the delicate interfaces that connect (and divide protein molecules and the neighboring electrolyte solution.

  16. A salt water battery with high stability and charging rates made from solution processed conjugated polymers with polar side chains

    OpenAIRE

    Moia, Davide; Giovannitti, Alexander; Szumska, Anna A.; Schnurr, Martin; Rezasoltani, Elham; Maria, Iuliana P.; Barnes, Piers R. F.; McCulloch, Iain; Nelson, Jenny

    2017-01-01

    We report a neutral salt water based battery which uses p-type and n-type solution processed polymer films as the cathode and the anode of the cell. The specific capacity of the electrodes (approximately 30 mAh cm-3) is achieved via formation of bipolarons in both the p-type and n-type polymers. By engineering ethylene glycol and zwitterion based side chains attached to the polymer backbone we facilitate rapid ion transport through the non-porous polymer films. This, combined with efficient t...

  17. 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.

  18. 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.

  19. Surface-bubble-modulated liquid chromatography: a new approach for manipulation of chromatographic retention and investigation of solute distribution at water/hydrophobic interfaces.

    Science.gov (United States)

    Nakamura, Keisuke; Nakamura, Hiroki; Saito, Shingo; Shibukawa, Masami

    2015-01-20

    In this paper, we present a new chromatographic method termed surface-bubble-modulated liquid chromatography (SBMLC), that has a hybrid separation medium incorporated with surface nanobubbles. Nanobubbles or nanoscale gas phases can be fixed at the interface between water and a hydrophobic material by delivering water into a dry column packed with a nanoporous material. The incorporation of a gas phase at the hydrophobic surface leads to the formation of the hybrid separation system consisting of the gas phase, hydrophobic moieties, and the water/hydrophobic interface or the interfacial water. One can change the volume of the gas phase by pressure applied to the column, which in turn alters the area of water/hydrophobic interface or the volume of the interfacial water, while the amount of the hydrophobic moiety remains constant. Therefore, this strategy provides a novel technique not only for manipulating the separation selectivity by pressure but also for elucidating the mechanism of accumulation or retention of solute compounds in aqueous solutions by a hydrophobic material. We evaluate the contributions of the interfacial water at the surface of an octadecyl bonded silica and the bonded layer itself to the retention of various solute compounds in aqueous solutions on the column packed with the material by SBMLC. The results show that the interfacial water formed at the hydrophobic surface has a key role in retention even though its volume is rather small. The manipulation of the separation selectivity of SBMLC for some organic compounds by pressure is demonstrated.

  20. Limitations of amorphous content quantification by isothermal calorimetry using saturated salt solutions to control relative humidity: alternative methods.

    Science.gov (United States)

    Khalef, Nawel; Pinal, Rodolfo; Bakri, Aziz

    2010-04-01

    Despite the high sensitivity of isothermal calorimetry (IC), reported measurements of amorphous content by this technique show significant variability even for the same compound. An investigation into the reasons behind such variability is presented using amorphous lactose and salbutamol sulfate as model compounds. An analysis was carried out on the heat evolved as a result of the exchange of water vapor between the solid sample during crystallization and the saline solution reservoir. The use of saturated salt solutions as means of control of the vapor pressure of water within sealed ampoules bears inherent limitations that lead in turn to the variability associated with the IC technique. We present an alternative IC method, based on an open cell configuration that effectively addresses the limitations encountered with the sealed ampoule system. The proposed approach yields an integral whose value is proportional to the amorphous content in the sample, thus enabling reliable and consistent quantifications. 2009 Wiley-Liss, Inc. and the American Pharmacists Association

  1. Carbon nanotube thermal interfaces and related applications

    Science.gov (United States)

    Hodson, Stephen L.

    compressive load. The thermal performance was further improved by infiltrating the CNT TIM with paraffin wax, which serves as an alternate pathway for heat conduction across the interface that ultimately reduces the bulk thermal resistance of the CNT TIM. For CNT TIMs synthesized at the Birck Nanotechnology Center at Purdue University, the thermal resistance was shown to scale linearly with their aggregate, as-grown height. Thus, the bulk thermal resistance can alternatively be tuned by adjusting the as-grown height. The linear relationship between thermal resistance and CNT TIM height provides a simple and efficient methodology to estimate the contact resistance and effective thermal conductivity of CNT TIMs. In this work, the contact resistance and effective thermal conductivity were estimated using two measurement techniques: (i) one-dimensional, steady-state reference bar and (ii) photoacoustic technique. A discrepancy in the estimated contact resistance exists between the two measurement techniques, which is due to the difficulty in measuring the true contact area. In contrast, the effective thermal conductivities estimated from both measurement techniques moderately agreed and were estimated to be on the order of O(1 W/mK). The final chapter is in collaboration with Sandia National Laboratories and focuses on the development of an apparatus to measure the thermal conductivity of insulation materials critical for the operation of molten salt batteries. Molten salt batteries are particularly useful power sources for radar and guidance systems in military applications such as guided missiles, ordinance, and other weapons. Molten salt batteries are activated by raising the temperature of the electrolyte above its melting temperature using pyrotechnic heat pellets. The battery will remain active as long as the electrolyte is molten. As a result, the thermal processes within the components and interactions between them are critical to the overall performance of molten salt

  2. 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

  3. Kinematics and dynamics of salt movement driven by sub-salt normal faulting and supra-salt sediment accumulation - combined analogue experiments and analytical calculations

    Science.gov (United States)

    Warsitzka, Michael; Kukowski, Nina; Kley, Jonas

    2017-04-01

    In extensional sedimentary basins, the movement of ductile salt is mainly controlled by the vertical displacement of the salt layer, differential loading due to syn-kinematic deposition, and tectonic shearing at the top and the base of the salt layer. During basement normal faulting, salt either tends to flow downward to the basin centre driven by its own weight or it is squeezed upward due to differential loading. In analogue experiments and analytical models, we address the interplay between normal faulting of the sub-salt basement, compaction and density inversion of the supra-salt cover and the kinematic response of the ductile salt layer. The analogue experiments consist of a ductile substratum (silicone putty) beneath a denser cover layer (sand mixture). Both layers are displaced by normal faults mimicked through a downward moving block within the rigid base of the experimental apparatus and the resulting flow patterns in the ductile layer are monitored and analysed. In the computational models using an analytical approximative solution of the Navier-Stokes equation, the steady-state flow velocity in an idealized natural salt layer is calculated in order to evaluate how flow patterns observed in the analogue experiments can be translated to nature. The analytical calculations provide estimations of the prevailing direction and velocity of salt flow above a sub-salt normal fault. The results of both modelling approaches show that under most geological conditions salt moves downwards to the hanging wall side as long as vertical offset and compaction of the cover layer are small. As soon as an effective average density of the cover is exceeded, the direction of the flow velocity reverses and the viscous material is squeezed towards the elevated footwall side. The analytical models reveal that upward flow occurs even if the average density of the overburden does not exceed the density of salt. By testing various scenarios with different layer thicknesses

  4. 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.

  5. Lime mortar with mixed in crystallization modifiers to mitigate salt damage

    NARCIS (Netherlands)

    Granneman, S.J.C.; Lubelli, B.; Hees, R.P.J. van

    2016-01-01

    Although salt crystallization damage is a widespread damage process in the porous materials of our built cultural heritage, no definite solution yet exists to improve the durability of materials with respect to salt crystallization. Most research focuses on improving material properties, whereas

  6. Geohydrology of the Keechi, Mount Sylvan, Oakwood, and Palestine salt domes in the northeast Texas salt-dome basin

    International Nuclear Information System (INIS)

    Carr, J.E.; Halasz, S.J.; Peters, H.B.

    1980-01-01

    The salt within these domes has penetrated as much as 20,000 feet of Mesozoic and Cenozoic strata, and presently extends to within 120 to 800 feet of the land surface. The salt penetrates or closely underlies major freshwater and salinewater aquifers within the basin. To provide a safe repository for radioactive wastes within one or more of these domes, a thorough understanding of the geohydrology needs to be obtained, and the hydrologic stability of the domes needs to be established for the expected life of the storage facility. Dissolution may exist at all four candidate salt domes, possibly through contact with Cretaceous or Tertiary aquifers, or through fault systems in the vicinity of the domes. Strata overlying and surrounding Palestine and Keechi Salt Domes have been arched into steeply-dipping folds that are complexly faulted. Similar conditions exist at Oakwood and Mount Sylvan Domes, except that the Tertiary strata have been only moderately disturbed. Additional problems concerning the hydrologic stability of Oakwood and Palestine Salt Domes have resulted from the disposal of oil-field salinewater in the cap rock at the Oakwood Dome and previous solution mining of salt at the Palestine Dome

  7. Evaluation of layered zinc hydroxide nitrate and zinc/nickel double hydroxide salts in the removal of chromate ions from solutions

    Energy Technology Data Exchange (ETDEWEB)

    Bortolaz de Oliveira, Henrique; Wypych, Fernando, E-mail: wypych@ufpr.br

    2016-11-15

    Layered zinc hydroxide nitrate (ZnHN) and Zn/Ni layered double hydroxide salts were synthesized and used to remove chromate ions from solutions at pH 8.0. The materials were characterized by many instrumental techniques before and after chromate ion removal. ZnHN decomposed after contact with the chromate solution, whereas the layered structure of Zn/Ni hydroxide nitrate (Zn/NiHN) and Zn/Ni hydroxide acetate (Zn/NiHA) remained their layers intact after the topotactic anionic exchange reaction, only changing the basal distances. ZnHN, Zn/NiHN, and Zn/NiHA removed 210.1, 144.8, and 170.1 mg of CrO{sub 4}{sup 2−}/g of material, respectively. Although the removal values obtained for Zn/NiHN and Zn/NiHA were smaller than the values predicted for the ideal formulas of the solids (194.3 and 192.4 mg of CrO{sub 4}{sup 2−}/g of material, respectively), the measured capacities were higher than the values achieved with many materials reported in the literature. Kinetic experiments showed the removal reaction was fast. To facilitate the solid/liquid separation process after chromium removal, Zn/Ni layered double hydroxide salts with magnetic supports were also synthesized, and their ability to remove chromate was evaluated. - Highlights: • Zinc hydroxide nitrate and Zn/Ni hydroxide nitrate or acetate were synthesized. • The interlayer anions were replaced by chromate anions at pH=8.0. • Only Zn/Ni hydroxide nitrate or acetate have the structure preserved after exchange. • Fast exchange reaction and high capacity of chromate removal were observed. • Magnetic materials were obtained to facilitate the solids removal the from solutions.

  8. Oriented crystalline monolayers and bilayers of 2 x 2 silver(1) grid architectures at the air-solution interface: Their assembly and crystal structure elucidation

    DEFF Research Database (Denmark)

    Weissbuch, J.; Baxter, P.N.W.; Kuzmenko, I.

    2000-01-01

    Oriented crystalline monolayers, similar to 14 Angstrom thick, of a 2 x 2 Ag+ grid complex, self-assembled at the air-solution interface starting from an water-insoluble ligand 3,6-bis[2-(6-phenylpyridine)]pyridazine spread on silver-ion-containing solutions,were examined by grazing-incidence X...

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

    African Journals Online (AJOL)

    Purpose: To investigate the effect of chitosan (CS) salt forms and pH condition on the transepithelial electrical resistance (TEER) of Caco-2 cell monolayer for enhanced permeability. Methods: Solutions (2 %w/v) of four different salt forms of CS-aspartate (CS-A), CS-ethylene diamine tetraacetate (CS-EDTA), ...

  10. Solution self-assembly and adsorption at the air-water interface of the monorhamnose and dirhamnose rhamnolipids and their mixtures.

    Science.gov (United States)

    Chen, M L; Penfold, J; Thomas, R K; Smyth, T J P; Perfumo, A; Marchant, R; Banat, I M; Stevenson, P; Parry, A; Tucker, I; Grillo, I

    2010-12-07

    The self-assembly in solution and adsorption at the air-water interface, measured by small-angle neutron scattering, SANS, and neutron reflectivity, NR, of the monorhamnose and dirhamnose rhamnolipids (R1, R2) and their mixtures, are discussed. The production of the deuterium-labeled rhamnolipids (required for the NR studies) from a Pseudomonas aeruginosa culture and their separation into the pure R1 and R2 components is described. At the air-water interface, R1 and R2 exhibit Langmuir-like adsorption isotherms, with saturated area/molecule values of about 60 and 75 Å(2), respectively. In R1/R2 mixtures, there is a strong partitioning of R1 to the surface and R2 competes less favorably because of the steric or packing constraints of the larger R2 dirhamnose headgroup. In dilute solution (<20 mM), R1 and R2 form small globular micelles, L(1), with aggregation numbers of about 50 and 30, respectively. At higher solution concentrations, R1 has a predominantly planar structure, L(α) (unilamellar, ULV, or bilamellar, BLV, vesicles) whereas R2 remains globular, with an aggregation number that increases with increasing surfactant concentration. For R1/R2 mixtures, solutions rich in R2 are predominantly micellar whereas solutions rich in R1 have a more planar structure. At an intermediate composition (60 to 80 mol % R1), there are mixed L(α)/L(1) and L(1)/L(α) regions. However, the higher preferred curvature associated with R2 tends to dominate the mixed R1/R2 microstructure and its associated phase behavior.

  11. A non-multimacrocyclic heteroditopic receptor that cooperatively binds and effectively extracts KAcO salt.

    Science.gov (United States)

    Zakrzewski, Maciej; Kwietniewska, Natalia; Walczak, Wojciech; Piątek, Piotr

    2018-06-06

    Prepared in only three synthetic steps, a non-multimacrocyclic heteroditopic receptor binds potassium salts of halides and carboxylates with unusually high cooperativity, suggesting salt binding as associated ion-pairs. Unprecedented extraction of highly hydrophilic KAcO salt from water to organic solution is also demonstrated.

  12. Disposal of decontaminated salts at the Savannah River Plant by solidification and burial

    International Nuclear Information System (INIS)

    Dukes, M.D.; Wolf, H.C.; Langton, C.A.

    1983-01-01

    The current plan for disposal of waste salt at the Savannah River Plant (SRP) is to immobilize the decontaminated salt solution by mixing with cement and SRP soil, and bury the resulting grout (saltstone) in a landfill. The grout which contains 37.8 wt % salt solution, 22.8 wt % Portland I-P cement, and 39.2 wt % SRP soil, was specially formulated to have a low permeability ( -10 cm/sec). This material will be mixed and placed in trenches. After setting, the saltstone will be covered with a clay cap, and an overburden of compacted native soil will be replaced. 6 references

  13. Analytical Solution for Interface Flow to a Sink With an Upconed Saline Water Lens: Strack's Regimes Revisited

    Science.gov (United States)

    Kacimov, A. R.; Obnosov, Y. V.

    2018-01-01

    A study is made of a steady, two-dimensional groundwater flow with a horizontal well (drain), which pumps out freshwater from an aquifer sandwiched between a horizontal bedrock and ponded soil surface, and containing a lens-shaped static volume of a heavier saline water (DNAPL-dense nonaqueous phase liquid) as a free surface. For flow toward a line sink, an explicit analytical solution is obtained by a conformal mapping of the hexagon in the complex potential plane onto a reference plane and the Keldysh-Sedov integral representation of a mixed boundary-value problem for a complex physical coordinate. The interface is found as a function of the pumping rate, the well locus, the ratio of liquid densities, and the hydraulic heads at the soil surface and in the well. The shape with two inflexion points and fronts varies from a small-thickness bedrock-spread pancake to a critical curvilinear triangle, which cusps toward the sink. The problem is mathematically solvable in a relatively narrow band of geometric and hydraulic parameters. A similar analytic solution for a static heavy bubble confined by a closed-curve interface (no contact with the bedrock) is outlined as an illustration of the method to solve a mixed boundary-value problem.

  14. Distinct Osmoadaptation Strategies in the Strict Halophilic and Halotolerant Bacteria Isolated from Lunsu Salt Water Body of North West Himalayas.

    Science.gov (United States)

    Vaidya, Shivani; Dev, Kamal; Sourirajan, Anuradha

    2018-07-01

    Two strict halophilic bacterial strains, Halobacillus trueperi SS1, and Halobacillus trueperi SS3, and three halotolerant bacterial strains, Shewanella algae SS2, Halomonas venusta SS5, and Marinomonas sp. SS8 of Lunsu salt water body, Himachal Pradesh, India, were selected to study the mechanism of salt tolerance and the role of osmolytes therein. A combination of flame photometry, chromatographic and colorimetric assays was used to study the mechanism of salt tolerance in the selected strict halophilic and halotolerant bacterial strains. The strict halophiles and, one of the halotolerants, Marinomonas sp. SS8 were found to utilize both "salt-in strategy" and "accumulation of compatible solutes strategy" for osmoregulation in hypersaline conditions. On the contrary, the remaining two halotolerants used "accumulation of compatible solutes strategy" under saline stress and not the "salt-in strategy". The present study suggests towards distinct mechanisms of salt tolerance in the two classes, wherein strict halophiles accumulate compatible solutes as well as adopt salt-in strategy, while the halotolerant bacteria accumulate a range of compatible solutes, except Marinomonas sp. SS8, which utilizes both the strategies to combat salt stress.

  15. The immiscible aqueous solutions of alkyl phosphates. Study for the purpose of uranium extraction from phosphoric acid solutions

    International Nuclear Information System (INIS)

    Mauborgne, Bernard

    1979-01-01

    Systems of immiscible aqueous solutions composed by a phase rich in mineral salt and by another phase almost totally containing an organic salt, have been studied for years, with quaternary ammonium salts with an organic cation. The objective of this research is to study systems symmetric to the previous ones, i.e. with organic anions such as alkyl phosphates, and then to try to understand mechanisms of extraction of metals in these environments. Based on properties of immiscible aqueous solutions, an original three-phase process of liquid-liquid extraction has been developed, and is used to separate uranium in phosphoric acids with better performance than the existing industrial processes [fr

  16. Molten Salt Power Tower Cost Model for the System Advisor Model (SAM)

    Energy Technology Data Exchange (ETDEWEB)

    Turchi, C. S.; Heath, G. A.

    2013-02-01

    This report describes a component-based cost model developed for molten-salt power tower solar power plants. The cost model was developed by the National Renewable Energy Laboratory (NREL), using data from several prior studies, including a contracted analysis from WorleyParsons Group, which is included herein as an Appendix. The WorleyParsons' analysis also estimated material composition and mass for the plant to facilitate a life cycle analysis of the molten salt power tower technology. Details of the life cycle assessment have been published elsewhere. The cost model provides a reference plant that interfaces with NREL's System Advisor Model or SAM. The reference plant assumes a nominal 100-MWe (net) power tower running with a nitrate salt heat transfer fluid (HTF). Thermal energy storage is provided by direct storage of the HTF in a two-tank system. The design assumes dry-cooling. The model includes a spreadsheet that interfaces with SAM via the Excel Exchange option in SAM. The spreadsheet allows users to estimate the costs of different-size plants and to take into account changes in commodity prices. This report and the accompanying Excel spreadsheet can be downloaded at https://sam.nrel.gov/cost.

  17. Research on Dynamic Dissolving Model and Experiment for Rock Salt under Different Flow Conditions

    Directory of Open Access Journals (Sweden)

    Xinrong Liu

    2015-01-01

    Full Text Available Utilizing deep rock salt cavern is not only a widely recognized energy reserve method but also a key development direction for implementing the energy strategic reserve plan. And rock salt cavern adopts solution mining techniques to realize building cavity. In view of this, the paper, based on the dissolving properties of rock salt, being simplified and hypothesized the dynamic dissolving process of rock salt, combined conditions between dissolution effect and seepage effect in establishing dynamic dissolving models of rock salt under different flow quantities. Devices were also designed to test the dynamic dissolving process for rock salt samples under different flow quantities and then utilized the finite-difference method to find the numerical solution of the dynamic dissolving model. The artificial intelligence algorithm, Particle Swarm Optimization algorithm (PSO, was finally introduced to conduct inverse analysis of parameters on the established model, whose calculation results coincide with the experimental data.

  18. Entropy of adsorption of mixed surfactants from solutions onto the air/water interface

    Science.gov (United States)

    Chen, L.-W.; Chen, J.-H.; Zhou, N.-F.

    1995-01-01

    The partial molar entropy change for mixed surfactant molecules adsorbed from solution at the air/water interface has been investigated by surface thermodynamics based upon the experimental surface tension isotherms at various temperatures. Results for different surfactant mixtures of sodium dodecyl sulfate and sodium tetradecyl sulfate, decylpyridinium chloride and sodium alkylsulfonates have shown that the partial molar entropy changes for adsorption of the mixed surfactants were generally negative and decreased with increasing adsorption to a minimum near the maximum adsorption and then increased abruptly. The entropy decrease can be explained by the adsorption-orientation of surfactant molecules in the adsorbed monolayer and the abrupt entropy increase at the maximum adsorption is possible due to the strong repulsion between the adsorbed molecules.

  19. 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.

  20. Regular multi-sequences copolymers study at interfaces and in solution; Etude des copolymeres multisequences reguliers aux interfaces et en solution

    Energy Technology Data Exchange (ETDEWEB)

    Leclerc, E.

    1996-11-15

    In this study are described the conformations which are taken by multi-sequences copolymers in various situations. The phase diagram of copolymers near an interface defined by two non-miscible liquids has been given, respectively for a strongly adsorbing interface and for a weakly adsorbing interface. The passage between these two extreme conditions has revealed the existence of a lot of intermediate conditions. Copolymers have also been studied with several solvents of different quality. The formation of folded structures described by micellar structures have been studied according to the size of the respective sequences in a ``good`` solvent and in a ``bad`` solvent. The obtention of ``flower`` micelles is due to very strict conditions on the solvent quality and on the sequences size. The phase diagram of the different micellar structures has then been established. Jointly to this theoretical study, an experimental work has been developed on a model protein: the {beta} casein. The main characteristic parameters of the aggregates formed by the protein have been established by experiments of small angle neutrons scattering. The interactions which are present between macromolecules are strongly attractive at low concentration (formation of micelles) and repulsive when the concentration increases. Some resemblances exist between the micelles formed by the copolymers and the aggregates formed by the {beta} casein. (O.M.) 141 refs.

  1. RIGOR MORTIS AND THE INFLUENCE OF CALCIUM AND MAGNESIUM SALTS UPON ITS DEVELOPMENT.

    Science.gov (United States)

    Meltzer, S J; Auer, J

    1908-01-01

    Calcium salts hasten and magnesium salts retard the development of rigor mortis, that is, when these salts are administered subcutaneously or intravenously. When injected intra-arterially, concentrated solutions of both kinds of salts cause nearly an immediate onset of a strong stiffness of the muscles which is apparently a contraction, brought on by a stimulation caused by these salts and due to osmosis. This contraction, if strong, passes over without a relaxation into a real rigor. This form of rigor may be classed as work-rigor (Arbeitsstarre). In animals, at least in frogs, with intact cords, the early contraction and the following rigor are stronger than in animals with destroyed cord. If M/8 solutions-nearly equimolecular to "physiological" solutions of sodium chloride-are used, even when injected intra-arterially, calcium salts hasten and magnesium salts retard the onset of rigor. The hastening and retardation in this case as well as in the cases of subcutaneous and intravenous injections, are ion effects and essentially due to the cations, calcium and magnesium. In the rigor hastened by calcium the effects of the extensor muscles mostly prevail; in the rigor following magnesium injection, on the other hand, either the flexor muscles prevail or the muscles become stiff in the original position of the animal at death. There seems to be no difference in the degree of stiffness in the final rigor, only the onset and development of the rigor is hastened in the case of the one salt and retarded in the other. Calcium hastens also the development of heat rigor. No positive facts were obtained with regard to the effect of magnesium upon heat vigor. Calcium also hastens and magnesium retards the onset of rigor in the left ventricle of the heart. No definite data were gathered with regard to the effects of these salts upon the right ventricle.

  2. Radiological consequences associated with human intrusion into radioactive waste repositories in salt formations

    International Nuclear Information System (INIS)

    Jacquier, P.

    1989-01-01

    The assessment of the radiological impact of human intrusion scenarios is extremely important in the case of repositories located in salt formations, since salt is obviously a valuable economic resource. Salt formations also represent a suitable medium for mining storage caverns for oil and gas. The scenario considered in this report is that of solution mining in salt formations to produce salt for human consumption. It is postulated that the salt is extracted by excavating a cavern through solution-mining and that, in the course of cavern enlargement, the waste is intercepted and drops to the bottom of the cavern. We have assumed that the intrusion takes place 500 or even 2 500 years after the repository has been sealed. The cases considered involve high-level vitrified waste or cemented alpha waste. The paper describes the assumptions on which the scenario is based and uses a simplified model to assess the radiological consequences associated with the ingestion of contaminated salt. The paper also provides details of a sensitivity/uncertainty analysis which identified several areas in which experimental studies should be either initiated or continued [fr

  3. Interactions of PAMAM dendrimers with SDS at the solid-liquid interface.

    Science.gov (United States)

    Arteta, Marianna Yanez; Eltes, Felix; Campbell, Richard A; Nylander, Tommy

    2013-05-14

    This work addresses structural and nonequilibrium effects of the interactions between well-defined cationic poly(amidoamine) PAMAM dendrimers of generations 4 and 8 and the anionic surfactant sodium dodecyl sulfate (SDS) at the hydrophilic silica-water interface. Neutron reflectometry and quartz crystal microbalance with dissipation monitoring were used to reveal the adsorption from premixed dendrimer/surfactant solutions as well as sequential addition of the surfactant to preadsorbed layers of dendrimers. PAMAM dendrimers of both generations adsorb to hydrophilic silica as a compact monolayer, and the adsorption is irreversible upon rinsing with salt solution. SDS adsorbs on the dendrimer layer and at low bulk concentrations causes the expansion of the dendrimer layers on the surface. When the bulk concentration of SDS is increased, the surfactant layer consists of aggregates or bilayer-like structures. The adsorption of surfactant is reversible upon rinsing, but slight changes of the structure of the preadsorbed PAMAM monolayer were observed. The adsorption from premixed solutions close to charge neutrality results in thick multilayers, but the surface excess is lower when the bulk complexes have a net negative charge. A critical examination of the pathway of adsorption for the interactions of SDS with preadsorbed PAMAM monolayers and premixed PAMAM/SDS solutions with hydrophilic silica revealed that nonequilibrium effects are important only in the latter case, and the application of a thermodynamic model to such experimental data would be inappropriate.

  4. 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

  5. Halide salts and their structural properties in presence of secondary amine based molecule: A combined experimental and theoretical analysis

    Science.gov (United States)

    Ghosh, Pritam; Hazra, Abhijit; Ghosh, Meenakshi; Chandra Murmu, Naresh; Banerjee, Priyabrata

    2018-04-01

    Biologically relevant halide salts and its solution state structural properties are always been significant. In general, exposure of halide salts into polar solution medium results in solvation which in turn separates the cationic and anionic part of the salt. However, the conventional behaviour of salts might alter in presence of any secondary amine based compound, i.e.; moderately strong Lewis acid. In its consequence, to investigate the effect of secondary amine based compound in the salt solution, novel (E)-2-(4-bromobenzylidene)-1-(perfluorophenyl) hydrazine has been synthesized and used as secondary amine source. The secondary amine compound interestingly shows a drastic color change upon exposure to fluoride salts owing to hydrogen bonding interaction. Several experimental methods, e.g.; SCXRD, UV-Vis, FT-IR, ESI-MS and DLS together with modern DFT (i.e.; DFT-D3) have been performed to explore the structural properties of the halide salts upon exposure to secondary amine based compound. The effect of counter cation of the fluoride salt in binding with secondary amine source has also been investigated.

  6. 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

  7. Radioactive waste and special waste disposal in salt domes - phoney waste management solutions

    International Nuclear Information System (INIS)

    Grimmel, E.

    1990-01-01

    The paper tries to make aware of the fact that an indefinite safe disposal of anthropogeneous wastes in underground repositories is impossible. Suspicion is raised that the Gorleben-Rambow salt dome has never been studied for its suitability as a repository, but that it was simply taken for granted. Safety analyses are meant only to conceal uncertainty. It is demanded to immediately opt out of the ultimate disposal technique for radioactive and special wastes in salt caverns. (DG) [de

  8. Ancient Wall Tiles – The Importance of the Glaze/Ceramic Interface in Glaze Detachment

    Directory of Open Access Journals (Sweden)

    Marisa COSTA

    2014-04-01

    Full Text Available One of the most severe pathologies suffered by early industrially produced tiles in Portugal in late nineteenth century is glaze detachment in wall tiles placed in the lower part of the façade. It is known that salts crystallize provoking the glaze detachment, destroying the waterproofing and the beauty of the wall tile and this is one of the crucial factors towards this occurrence. The present work questions the importance of the thickness of glaze/ceramic body interface, in what concerns glaze detachment provoked by salt crystallization. SEM-EDS was used to perform all the observations that lead to the conclusion that the exuberance of the interface between glaze and ceramic body has no influence in the resistance of the glaze to salt crystallization though time, being the porous network more determinant. DOI: http://dx.doi.org/10.5755/j01.ms.20.1.3815

  9. 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)

  10. Hydrological methods preferentially recover cesium from nuclear waste salt cake

    International Nuclear Information System (INIS)

    Brooke, J.N.; Hamm, L.L.

    1997-01-01

    The Savannah River Site is treating high level radioactive waste in the form of insoluble solids (sludge), crystallized salt (salt cake), and salt solutions. High costs and operational concerns have prompted DOE to look for ways to improve the salt cake treatment process. A numerical model was developed to evaluate the feasibility of pump and treat technology for extracting cesium from salt cake. A modified version of the VAM3DCG code was used to first establish a steady-state flow field, then to simulate 30 days of operation. Simulation results suggest that efficient cesium extraction can be obtained with low displacement volumes. The actual extraction process will probably be less impressive because of nonuniform properties. 2 refs., 2 figs

  11. Experimental determination of Henry's law constants of difluoromethane (HFC-32 and the salting-out effects in aqueous salt solutions relevant to seawater

    Directory of Open Access Journals (Sweden)

    S. Kutsuna

    2017-06-01

    Full Text Available Gas-to-water equilibrium coefficients, KeqS (in M atm−1, of difluoromethane (CH2F2, a hydrofluorocarbon refrigerant (HFC-32, in aqueous salt solutions relevant to seawater were determined over a temperature (T range from 276 to 313 K and a salinity (S range up to 51 ‰ by means of an inert-gas stripping method. From the van't Hoff equation, the KeqS value in water, which corresponds to the Henry's law constant (KH, at 298 K was determined to be 0.065 M atm−1. The salinity dependence of KeqS (the salting-out effect, ln(KH∕KeqS, did not obey the Sechenov equation but was proportional to S0. 5. Overall, the KeqS(T value was expressed by ln(KeqS(T  =  −49.71 + (77.70 − 0.134  ×  S0. 5  ×  (100∕T + 19.14  ×  ln(T∕100. By using this equation in a lower-tropospheric semi-hemisphere (30–90 °S of the Advanced Global Atmospheric Gases Experiment (AGAGE 12-box model, we estimated that 1 to 4 % of the atmospheric burden of CH2F2 resided in the ocean mixed layer and that this percentage was at least 4 % in the winter; dissolution of CH2F2 in the ocean may partially influence estimates of CH2F2 emissions from long-term observational data of atmospheric CH2F2 concentrations.

  12. Estimation of free acid content in lanthanide salt solution used for pH-potentiometric determination of their stability constants with organic ligands

    International Nuclear Information System (INIS)

    Zheltvaj, I.I.; Tishchenko, M.A.

    1985-01-01

    To improve the pH-potentiometric method for determining complex stability constants the possibility of alkalimetric titration of a free acid in the lanthanide perchlorate solution after binding metal ions by disodium salt of ethylene-diamine-tetraacetic acid is studied. The stability constants were determined from the difference between the total acid content after complexon addition and doubled metal cation content in the solution which has been preliminarily determined by the complexonometric method. It is shown that the alkaline (NaOH) equivalent quantities spent for free acid titration either in the absence or presence of the complexon is different. With increase of free acid content in the solution the difference in determinations with complexon and without it is somewhat reduced. Thus, the use of complexon contributes to a higher accuracy in determining the free acid, and in the first place in case of minor contents

  13. Geohydrolic studies of Gulf Coast interior salt domes

    International Nuclear Information System (INIS)

    Smith, C.G. Jr.

    1977-01-01

    Disposal of high-level radioactive wastes in Gulf Coast salt domes requires that the cavities be free from groundwater dissolution for 250,000 years. Salinity variations of groundwater near selected domes were investigated. Saline groundwater anomalies (saline plumes) in aquifers pierced or uplifted by the dome may be the result of salt solution by groundwater. In the Northeast Texas salt dome basin electric logs of oil and gas wells have been used to estimate groundwater salinities in aquifers near selected domes. Thus far, the analyses have revealed saline groundwater anomalies around 4 of the 9 domes studied. Estimates of the rate of salt dissolution from domes associated with saline groundwater plumes indicate that less than 30 meters of salt will be removed from the upper surfaces of the dome in 250,000 years. Thus, these preliminary studies show that even apparently unstable domes may be sufficiently stable to serve as waste disposal sites. 6 figures

  14. Comparison of salt solution and air drying methods for moisture fixation in highly porous building materials

    DEFF Research Database (Denmark)

    Antonov, Yovko Ivanov; Jensen, Rasmus Lund; Møldrup, Per

    2017-01-01

    In recent years, research has identified some bio-based, porous building materials as good or excellent regulators of moisture in buildings. The ability of a material to absorb, release and store moisture is described by vapour sorption isotherms. It is necessary input to simulations of indoor...... building materials by a standardized testing method, using saturated salt solutions. Furthermore, results from the standard method are compared to values of moisture content for the same materials, obtained by air-drying at different relative humidity. This is done with the aim to compare the findings from...... the two methods with respect to time and repeatability of the results. Derived isotherms are further used as direct input in the building simulation software BSim, which is capable of predicting indoor environment parameters by solving coupled, transient heat and moisture transport equations using finite...

  15. Salt attack in parking garage in block of flats

    Science.gov (United States)

    Beran, Pavel; Frankeová, Dita; Pavlík, Zbyšek

    2017-07-01

    In recent years many new block of flats with parking garages placed inside the buildings were constructed. This tendency brings beyond question benefits for residents and also for city planning, but it requires new design and structural approaches and advanced material and construction solutions. The analysis of plaster damage on partition wall in parking garage in one of these buildings is presented in the paper. The damage of studied plaster is caused by the salts which are transported together with snow on cars undercarriage into garage area during winter. The snow melts and water with dissolved salts is transported by the capillary suction from concrete floor into the rendered partition wall. Based on the interior temperature, adsorbed water with dissolved chlorides evaporates and from the over saturated pore solution are formed salt crystals that damages the surface plaster layers. This damage would not occur if the partition wall was correctly isolated from the floor finish layer in the parking garage.

  16. Salt ingestion caves.

    Directory of Open Access Journals (Sweden)

    Lundquist Charles A.

    2006-01-01

    Full Text Available Large vertebrate herbivores, when they find a salt-bearing layer of rock, say in a cliff face, can produce sizable voids where, overgenerations, they have removed and consumed salty rock. The cavities formed by this natural animal process constitute a uniqueclass of caves that can be called salt ingestion caves. Several examples of such caves are described in various publications. Anexample in Mississippi U.S.A., Rock House Cave, was visited by the authors in 2000. It seems to have been formed by deer orbison. Perhaps the most spectacular example is Kitum Cave in Kenya. This cave has been excavated to a length over 100 metersby elephants. An ancient example is La Cueva del Milodon in Chile, which is reported to have been excavated by the now extinctmilodon, a giant ground sloth. Still other possible examples can be cited. This class of caves deserves a careful definition. First, thecavity in rock should meet the size and other conventions of the locally accepted definition of a cave. Of course this requirement differsin detail from country to country, particularly in the matter of size. The intent is to respect the local conventions. The characteristicthat human entry is possible is judged to be a crucial property of any recognized cave definition. Second, the cavity should besignificantly the result of vertebrate animal consumption of salt-bearing rock. The defining process is that rock removed to form thecave is carried away in the digestive track of an animal. While sodium salts are expected to be the norm, other salts for which thereis animal hunger are acceptable. Also some other speleogenesis process, such as solution, should not be excluded as long as it issecondary in formation of a cave in question.

  17. 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).

  18. Physiological Evaluation of Alkali-Salt Tolerance of Thirty Switchgrass (Panicum virgatum Lines.

    Directory of Open Access Journals (Sweden)

    Guofu Hu

    Full Text Available Soil salt-alkalization is a major limiting factor for crop production in many regions. Switchgrass (Panicum virgatum L. is a warm-season C4 perennial rhizomatous bunchgrass and a target lignocellulosic biofuel species. The objective of this study was to evaluate relative alkali-salt tolerance among 30 switchgrass lines. Tillers of each switchgrass line were transplanted into pots filled with fine sand. Two months after transplanting, plants at E5 developmental stage were grown in either half strength Hoagland's nutrient solution with 0 mM Na+ (control or half strength Hoagland's nutrient solution with 150 mM Na+ and pH of 9.5 (alkali-salt stress treatment for 20 d. Alkali-salt stress damaged cell membranes [higher electrolyte leakage (EL], reduced leaf relative water content (RWC, net photosynthetic rate (Pn, stomatal conductance (gs, and transpiration rate (Tr. An alkali-salt stress tolerance trait index (ASTTI for each parameter was calculated based on the ratio of the value under alkali-salt stress and the value under non-stress conditions for each parameter of each line. Relative alkali-salt tolerance was determined based on principal components analysis and cluster analysis of the physiological parameters and their ASTTI values. Significant differences in alkali-salt stress tolerance were found among the 30 lines. Lowland lines TEM-SEC, Alamo, TEM-SLC and Kanlow were classified as alkali-salt tolerant. In contrast, three lowland lines (AM-314/MS-155, BN-13645-64 and two upland lines (Caddo and Blackwell-1 were classified as alkali-salt sensitive. The results suggest wide variations exist in alkali-salt stress tolerance among the 30 switchgrass lines. The approach of using a combination of principal components and cluster analysis of the physiological parameters and related ASTTI is feasible for evaluating alkali-salt tolerance in switchgrass.

  19. Physiological Evaluation of Alkali-Salt Tolerance of Thirty Switchgrass (Panicum virgatum) Lines.

    Science.gov (United States)

    Hu, Guofu; Liu, Yiming; Zhang, Xunzhong; Yao, Fengjiao; Huang, Yan; Ervin, Erik H; Zhao, Bingyu

    2015-01-01

    Soil salt-alkalization is a major limiting factor for crop production in many regions. Switchgrass (Panicum virgatum L.) is a warm-season C4 perennial rhizomatous bunchgrass and a target lignocellulosic biofuel species. The objective of this study was to evaluate relative alkali-salt tolerance among 30 switchgrass lines. Tillers of each switchgrass line were transplanted into pots filled with fine sand. Two months after transplanting, plants at E5 developmental stage were grown in either half strength Hoagland's nutrient solution with 0 mM Na+ (control) or half strength Hoagland's nutrient solution with 150 mM Na+ and pH of 9.5 (alkali-salt stress treatment) for 20 d. Alkali-salt stress damaged cell membranes [higher electrolyte leakage (EL)], reduced leaf relative water content (RWC), net photosynthetic rate (Pn), stomatal conductance (gs), and transpiration rate (Tr). An alkali-salt stress tolerance trait index (ASTTI) for each parameter was calculated based on the ratio of the value under alkali-salt stress and the value under non-stress conditions for each parameter of each line. Relative alkali-salt tolerance was determined based on principal components analysis and cluster analysis of the physiological parameters and their ASTTI values. Significant differences in alkali-salt stress tolerance were found among the 30 lines. Lowland lines TEM-SEC, Alamo, TEM-SLC and Kanlow were classified as alkali-salt tolerant. In contrast, three lowland lines (AM-314/MS-155, BN-13645-64) and two upland lines (Caddo and Blackwell-1) were classified as alkali-salt sensitive. The results suggest wide variations exist in alkali-salt stress tolerance among the 30 switchgrass lines. The approach of using a combination of principal components and cluster analysis of the physiological parameters and related ASTTI is feasible for evaluating alkali-salt tolerance in switchgrass.

  20. The effect of salt composition on reductive extraction of some typical elements from molten LiF-BeF2 salt into liquid bismuth

    International Nuclear Information System (INIS)

    Hirotake, M.; Jun, O.; Kimikazu, M.; Kunimitsu, Y.; Yasunobu, T.

    1983-01-01

    The distribution coefficients of thorium and radium between molten LiF-BeF 2 and liquid bismuth solutions were measured at 600 0 C in support of the processing of the molten-salt breeder reactor (MSBR) fuel. The increasing mole fraction of LiF in the salt phase from 40 to 70 mol% resulted in the rapid decrease of the distribution coefficient of thorium and in the slow decrease of that of radium. A comprehensive correlation of distribution behavior with salt composition is given by taking into account the formation of complex ions. The equilibrium distribution data affirm that thorium and radium exist mainly as Li 2 ThF 6 and RaF 2 , respectively, in the salt phase. It is suggested that the lower mole fraction of LiF in the fuel salt is effective in the MSBR fuel processing

  1. 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...

  2. SFG study on potential-dependent structure of water at Pt electrode/electrolyte solution interface

    Energy Technology Data Exchange (ETDEWEB)

    Noguchi, Hidenori; Okada, Tsubasa; Uosaki, Kohei [Physical Chemistry Laboratory, Division of Chemistry, Graduate School of Science, Hokkaido University, Sapporo 060-0810 (Japan)

    2008-10-01

    Structure of water at Pt/electrolyte solution interface was investigated by sum frequency generation (SFG) spectroscopy. Two broad peaks were observed in OH stretching region at ca. 3200 cm{sup -1} and ca. 3400 cm{sup -1}, which are known to be due to the symmetric OH stretching (U{sub 1}) of tetrahedrally coordinated, i.e., strongly hydrogen bonded 'ice-like' water, and the asymmetric OH stretching (U{sub 3}) of water molecules in a more random arrangement, i.e., weakly hydrogen bonded 'liquid-like' water, respectively. The SFG intensity strongly depended on electrode potential. Several possibilities are suggested for the potential dependence of the SFG intensity. (author)

  3. 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....

  4. Sub-stoichiometric isotope dilution analysis method for the determination of iodine in common salts using iodine-131 tracer

    International Nuclear Information System (INIS)

    Singh, Vivek; Garg, A.N.

    1994-01-01

    A sub-stoichiometric isotope dilution analysis (SIDA) method was developed for the determination of iodine in different brands of common salts. An aqueous salt solution containing 131 I tracer and NaI as carrier is oxidized by tartaric acid and KIO 3 and the liberated iodine is extracted with CCl 4 . To the extract an aqueous solution of AgNO 3 is added in substoichiometric amount to obtain a colloidal solution of AgI. On adding sodium thiosulfate solution, the NaI so formed passes into aqueous solution, which is then counted. Several different brands of salt were analysed. The method is especially suitable for the determination of microgram amounts of iodide in the presence of excess of chloride. (Author)

  5. 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.'

  6. 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...

  7. Estimation of the depth to the fresh-water/salt-water interface from vertical head gradients in wells in coastal and island aquifers

    Science.gov (United States)

    Izuka, Scot K.; Gingerich, Stephen B.

    An accurate estimate of the depth to the theoretical interface between fresh, water and salt water is critical to estimates of well yields in coastal and island aquifers. The Ghyben-Herzberg relation, which is commonly used to estimate interface depth, can greatly underestimate or overestimate the fresh-water thickness, because it assumes no vertical head gradients and no vertical flow. Estimation of the interface depth needs to consider the vertical head gradients and aquifer anisotropy that may be present. This paper presents a method to calculate vertical head gradients using water-level measurements made during drilling of a partially penetrating well; the gradient is then used to estimate interface depth. Application of the method to a numerically simulated fresh-water/salt-water system shows that the method is most accurate when the gradient is measured in a deeply penetrating well. Even using a shallow well, the method more accurately estimates the interface position than does the Ghyben-Herzberg relation where substantial vertical head gradients exist. Application of the method to field data shows that drilling, collection methods of water-level data, and aquifer inhomogeneities can cause difficulties, but the effects of these difficulties can be minimized. Résumé Une estimation précise de la profondeur de l'interface théorique entre l'eau douce et l'eau salée est un élément critique dans les estimations de rendement des puits dans les aquifères insulaires et littoraux. La relation de Ghyben-Herzberg, qui est habituellement utilisée pour estimer la profondeur de cette interface, peut fortement sous-estimer ou surestimer l'épaisseur de l'eau douce, parce qu'elle suppose l'absence de gradient vertical de charge et d'écoulement vertical. L'estimation de la profondeur de l'interface requiert de prendre en considération les gradients verticaux de charge et l'éventuelle anisotropie de l'aquifère. Cet article propose une méthode de calcul des

  8. 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.

  9. Temperature and salt addition effects on the solubility behaviour of some phenolic compounds in water

    International Nuclear Information System (INIS)

    Noubigh, Adel; Abderrabba, Manef; Provost, Elise

    2007-01-01

    Solubility-temperature dependence data for six phenolic compounds (PhC), contained in olive mill wastewater (OMWW), in water and in some chloride salts (KCl, NaCl, and LiCl) aqueous solutions have been presented and solution standard molar enthalpies (Δ sol H 0 ) were determined using Van't Hoff plots. The temperature was varied from 293.15 K to 318.15 K. Solubility data were estimated using a thermostated reactor and HPLC analysis. It has been observed that solubility, in pure water and in aqueous chloride solutions, increases with increasing temperature. The salting-out LiCl > NaCl > KCl order obtained at 298.15 K is confirmed. Results were interpreted in terms of the salt hydration shells and the ability of the solute to form hydrogen-bond with water. The standard molar Gibbs free energies of transfer of PhC (Δ tr G 0 ) from pure water to aqueous solutions of the chloride salts have been calculated from the solubility data. In order to estimate the contribution of enthalpic and entropic terms, standard molar enthalpies (Δ tr H 0 ) and entropies (Δ tr S 0 ) of transfer have also been calculated. The decrease in solubility is correlated to the positive Δ tr G 0 value which is mainly of enthalpic origin

  10. Comparison of destructive and nondestructive assay of heterogeneous salt residues

    International Nuclear Information System (INIS)

    Fleissner, J.G.; Hume, M.W.

    1986-01-01

    To study problems associated with nondestructive assay (NDA) measurements of molten salt residues, a joint study was conducted by the Rocky Flats Plant, Golden, CO and Mound Laboratories, Miamisburg, OH. Extensive NDA measurements were made on nine containers of molten salt residues by both Rocky Flats and Mound followed by dissolution and solution quantification at Rocky Flats. Results of this study verify that plutonium and americium can be measured in such salt residues by a new gamma-ray spectral analysis technique coupled with calorimetry. Biases with respect to the segmented gamma-scan technique were noted

  11. Designing Interfaces

    CERN Document Server

    Tidwell, Jenifer

    2010-01-01

    Despite all of the UI toolkits available today, it's still not easy to design good application interfaces. This bestselling book is one of the few reliable sources to help you navigate through the maze of design options. By capturing UI best practices and reusable ideas as design patterns, Designing Interfaces provides solutions to common design problems that you can tailor to the situation at hand. This updated edition includes patterns for mobile apps and social media, as well as web applications and desktop software. Each pattern contains full-color examples and practical design advice th

  12. Selective solid-liquid extraction of lithium halide salts using a ditopic macrobicyclic receptor.

    Science.gov (United States)

    Mahoney, Joseph M; Beatty, Alicia M; Smith, Bradley D

    2004-11-29

    A ditopic salt receptor that is known to bind and extract solid NaCl, KCl, NaBr, and KBr into organic solution as their contact ion pairs is now shown by NMR and X-ray crystallography to bind and extract solid LiCl and LiBr as water-separated ion pairs. The receptor can transport these salts from an aqueous phase through a liquid organic membrane with a cation selectivity of K+ > Na+ > Li+. However, the selectivity order is strongly reversed when the receptor extracts solid alkali metal chlorides and bromides into organic solution. For a three-component mixture of solid LiCl, NaCl, and KCl, the ratio of salts extracted and complexed to the receptor in CDCl3 was 94:4:2, respectively. The same strong lithium selectivity was also observed in the case of a three-component mixture of solid LiBr, NaBr, and KBr where the ratio of extracted salts was 92:5:3. This observation is attributed to the unusually high solubility of lithium salts in organic solvents. The study suggests that ditopic receptors with an ability to extract solid salts as associated ion pairs may have application in separation processes.

  13. Free energy landscape of a minimalist salt bridge model.

    Science.gov (United States)

    Li, Xubin; Lv, Chao; Corbett, Karen M; Zheng, Lianqing; Wu, Dongsheng; Yang, Wei

    2016-01-01

    Salt bridges are essential to protein stability and dynamics. Despite the importance, there has been scarce of detailed discussion on how salt bridge partners interact with each other in distinct solvent exposed environments. In this study, employing a recent generalized orthogonal space tempering (gOST) method, we enabled efficient molecular dynamics simulation of repetitive breaking and reforming of salt bridge structures within a minimalist salt-bridge model, the Asp-Arg dipeptide and thereby were able to map its detailed free energy landscape in aqueous solution. Free energy surface analysis shows that although individually-solvated states are more favorable, salt-bridge states still occupy a noticeable portion of the overall population. Notably, the competing forces, e.g. intercharge attractions that drive the formation of salt bridges and solvation forces that pull the charged groups away from each other, are energetically comparable. As the result, the salt bridge stability is highly tunable by local environments; for instance when local water molecules are perturbed to interact more strongly with each other, the population of the salt-bridge states is likely to increase. Our results reveal the critical role of local solvent structures in modulating salt-bridge partner interactions and imply the importance of water fluctuations on conformational dynamics that involves solvent accessible salt bridge formations. © 2015 The Protein Society.

  14. Ionic diffusion in the double layer at model electrode/molten salt interfaces

    International Nuclear Information System (INIS)

    Tankeshwar, K.; Tosi, M.P.

    1991-08-01

    The anisotropic ionic diffusion coefficients in model electrochemical cells in the molten-salt regime for the electrolyte are evaluated from the ionic density profiles reported in simulation work of Grout and coworkers. A local description of the diffusion processes for counterions and coions in the electrical double layer is obtained from the data. (author). 10 refs, 1 fig., 1 tab

  15. SAVANNAH RIVER SITE INCIPIENT SLUDGE MIXING IN RADIOACTIVE LIQUID WASTE STORAGE TANKS DURING SALT SOLUTION BLENDING

    Energy Technology Data Exchange (ETDEWEB)

    Leishear, R.; Poirier, M.; Lee, S.; Steeper, T.; Fowley, M.; Parkinson, K.

    2011-01-12

    This paper is the second in a series of four publications to document ongoing pilot scale testing and computational fluid dynamics (CFD) modeling of mixing processes in 85 foot diameter, 1.3 million gallon, radioactive liquid waste, storage tanks at Savannah River Site (SRS). Homogeneous blending of salt solutions is required in waste tanks. Settled solids (i.e., sludge) are required to remain undisturbed on the bottom of waste tanks during blending. Suspension of sludge during blending may potentially release radiolytically generated hydrogen trapped in the sludge, which is a safety concern. The first paper (Leishear, et. al. [1]) presented pilot scale blending experiments of miscible fluids to provide initial design requirements for a full scale blending pump. Scaling techniques for an 8 foot diameter pilot scale tank were also justified in that work. This second paper describes the overall reasons to perform tests, and documents pilot scale experiments performed to investigate disturbance of sludge, using non-radioactive sludge simulants. A third paper will document pilot scale CFD modeling for comparison to experimental pilot scale test results for both blending tests and sludge disturbance tests. That paper will also describe full scale CFD results. The final paper will document additional blending test results for stratified layers in salt solutions, scale up techniques, final full scale pump design recommendations, and operational recommendations. Specifically, this paper documents a series of pilot scale tests, where sludge simulant disturbance due to a blending pump or transfer pump are investigated. A principle design requirement for a blending pump is UoD, where Uo is the pump discharge nozzle velocity, and D is the nozzle diameter. Pilot scale test results showed that sludge was undisturbed below UoD = 0.47 ft{sup 2}/s, and that below UoD = 0.58 ft{sup 2}/s minimal sludge disturbance was observed. If sludge is minimally disturbed, hydrogen will not be

  16. Water Evaporation from Acoustically Levitated Aqueous Solution Droplets.

    Science.gov (United States)

    Combe, Nicole A; Donaldson, D James

    2017-09-28

    We present a systematic study of the effect of solutes on the evaporation rate of acoustically levitated aqueous solution droplets by suspending individual droplets in a zero-relative humidity environment and measuring their size as a function of time. The ratios of the early time evaporation rates of six simple salts (NaCl, NaBr, NaNO 3 , KCl, MgCl 2 , CaCl 2 ) and malonic acid to that of water are in excellent agreement with predictions made by modifying the Maxwell equation to include the time-dependent water activity of the evaporating aqueous salt solution droplets. However, the early time evaporation rates of three ammonium salt solutions (NH 4 Cl, NH 4 NO 3 , (NH 4 ) 2 SO 4 ) are not significantly different from the evaporation rate of pure water. This finding is in accord with a previous report that ammonium sulfate does not depress the evaporation rate of its solutions, despite reducing its water vapor pressure, perhaps due to specific surface effects. At longer evaporation times, as the droplets approach crystallization, all but one (MgCl 2 ) of the solution evaporation rates are well described by the modified Maxwell equation.

  17. Location of microseismic swarms induced by salt solution mining

    Science.gov (United States)

    Kinscher, J.; Bernard, P.; Contrucci, I.; Mangeney, A.; Piguet, J. P.; Bigarre, P.

    2015-01-01

    Ground failures, caving processes and collapses of large natural or man-made underground cavities can produce significant socio-economic damages and represent a serious risk envisaged by the mine managements and municipalities. In order to improve our understanding of the mechanisms governing such a geohazard and to test the potential of geophysical methods to prevent them, the development and collapse of a salt solution mining cavity was monitored in the Lorraine basin in northeastern France. During the experiment, a huge microseismic data set (˜50 000 event files) was recorded by a local microseismic network. 80 per cent of the data comprised unusual swarming sequences with complex clusters of superimposed microseismic events which could not be processed through standard automatic detection and location routines. Here, we present two probabilistic methods which provide a powerful tool to assess the spatio-temporal characteristics of these swarming sequences in an automatic manner. Both methods take advantage of strong attenuation effects and significantly polarized P-wave energies at higher frequencies (>100 Hz). The first location approach uses simple signal amplitude estimates for different frequency bands, and an attenuation model to constrain the hypocentre locations. The second approach was designed to identify significantly polarized P-wave energies and the associated polarization angles which provide very valuable information on the hypocentre location. Both methods are applied to a microseismic data set recorded during an important step of the development of the cavity, that is, before its collapse. From our results, systematic spatio-temporal epicentre migration trends are observed in the order of seconds to minutes and several tens of meters which are partially associated with cyclic behaviours. In addition, from spatio-temporal distribution of epicentre clusters we observed similar epicentre migration in the order of hours and days. All together, we

  18. A novel bread making process using salt-stressed Baker's yeast.

    Science.gov (United States)

    Yeh, Lien-Te; Charles, Albert Linton; Ho, Chi-Tang; Huang, Tzou-Chi

    2009-01-01

    By adjusting the mixing order of ingredients in traditional formula, an innovative bread making process was developed. The effect of salt-stressed Baker's yeast on bread dough of different sugar levels was investigated. Baker's yeast was stressed in 7% salt solution then mixed into dough, which was then evaluated for fermentation time, dough fermentation producing gas, dough expansion, bread specific volumes, and sensory and physical properties. The results of this study indicated that salt-stressed Baker's yeast shortened fermentation time in 16% and 24% sugar dough. Forty minutes of salt stress produced significant amount of gas and increased bread specific volumes. The bread was softer and significantly improved sensory properties for aroma, taste, and overall acceptability were obtained.

  19. Soluble salts: their incidence on the protection of metallic structures by paint coatings

    International Nuclear Information System (INIS)

    Morcillo, M.

    2003-01-01

    The presence of soluble salts at the metal/paint interface is known to have a detrimental effect on the integrity of most paint systems. Though this is a long-standing problem, it has recently come to receive greater attention from the protective coatings industry. In the paper the following points are reviewed: degradation mechanisms of the metal/paint system, the role of the metallic substrate, the nature, origin and detection os soluble salts, expected levels of soluble salts in practice, critical thresholds of soluble salts and risk levels for premature failures, role of the type and thickness of paint systems and exposure conditions, and prevention measures. The author presents an overview of the subject, making reference to the related research that has been carried out by him and his co-workers over the last 16 years. (Author) 58 refs

  20. Calculation of solubility of salts in binary aqueous solutions

    International Nuclear Information System (INIS)

    Kolker, A.R.

    1990-01-01

    The possibility of theoretical calculation of solubility of some salts of the MX-type, where M - Na, K, Cs; X - F-I, as well as CsNO 3 and others forming no crystal hydrates in the solid phase, and the azeotropic composition in the water-HNO 3 system is studied. The calculational results of solubility are shown to depend very much on the values accepted for the standard free energies of component formation, melting heats and crystallization and on the difference in heat capacity of the melt and the solid phase