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Sample records for chloride ions determinacion

  1. Determination of the stability constants of lanthanum, praseodymium, europium, erbium and lutetium complexes with chloride ions; Determinacion de las constantes de estabilidad de los complejos de lantano, praseodimio, europio, erbio y lutecio con iones cloruro

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez R, E. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2008-07-01

    The stability constants of La{sup 3+}, Pr{sup 3+}, Eu{sup 3+}, Er{sup 3+} and Lu{sup 3+} chloride complexes were determined in perchloric acid media using a liquid-liquid extraction method. The dinonyl napthalene sulfonic acid in n-heptane was used as extractant. The lanthanide (Ln) concentrations were measured by a radiochemical (Eu and Lu) and a spectrophotometric (La, Pr, and Er) methods. In the last method, xylenol orange was used for the determinations at ph 6. The stability constants of lanthanum, praseodymium, erbium and lutetium chloride complexes were determined in 2, 3 and 4 M ionic strength and europium in 1, 2 and 3 M, at 303 K. The fitting of experimental data to the equations for the calculation of the stability constants, was carry out considering both one chemical species (LnCl{sup 2+}) or two chemical species (LnCl{sup 2+} and LnCl{sub 2}{sup +}). The Specific Ion Interaction Theory was applied to the values of log {beta}{sup I}{sub Ln},{sub Cl} and the first stability constants at zero ionic strength were calculated by extrapolation. The same theory could not be applied to the log {beta}{sup I}{sub Ln},{sub 2Cl}, due to its low abundance and the values determined for the stability constants were similar. The distribution diagrams of the chemical species were obtained using the program MEDUSA and considering log {beta}{sup I}{sub Ln},{sub CI}, log {beta}{sup I}{sub Ln},{sub 2CI} values obtained in this work and the hydrolysis constants taken from the literature. The lanthanide chloride complexes are present in solution at specific conditions of ionic strength, concentration and in the absence of hydrolysis. The log {beta}{sup I}{sub Ln},{sub Cl} data were related to the charge density and the corresponding equations were obtained. These equations could be used to determine the stability constants along the lanthanide series. (Author)

  2. Determination of lutetium (III) hydrolysis constants in the middle of ion force 1M sodium chloride at 303 K; Determinacion de las constantes de hidrolisis del lutecio (III), en medio de fuerza ionica 1M de cloruro de sodio, a 303 K

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez R, M.; Solache R, M.J. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Ramirez G, J.J.; Rojas H, A. [Universidad Autonoma Metropolitana-Iztapalapa, Mexico D.F. (Mexico). Dept. de Quimica

    1997-07-01

    With the purpose to complete information about the lutetium (III) hydrolysis constants here is used the potentiometric method to determine those in the middle of ion force 1M sodium chloride at 303 K. (Author)

  3. Diffusion behavior of chloride ions in concrete

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, T.; Gjoerv, O.E. [Norwegian Univ. of Science and Technology, Trondheim (Norway). Div. of Building Materials

    1996-06-01

    In the present paper, an analysis of the diffusion behavior of chloride ions in concrete is presented. In concentrated electrolytic aqueous solutions such as seawater or that typically used in laboratory experiments, the effect of ionic interaction may significantly reduce the chemical potential and thus the driving force of the diffusing species. Because of different drift velocities of the cations and chloride ions in the solution, the lagging motion of the cations will also retard the drift velocity of the chlorides. In addition, both the electrical double layer forming on the solid surface and the chemical binding may significantly interfere with the transport of the chloride ions. As a result, the diffusion behavior of the chloride ions in concrete is a more complex and complicated transport process than what can be described by Fick`s law of diffusion.

  4. Amperometric Sensor for Detection of Chloride Ions

    OpenAIRE

    Rene Kizek; Petr Babula; Jaromir Hubalek; Vojtech Adam; Libuse Trnkova

    2008-01-01

    Chloride ion sensing is important in many fields such as clinical diagnosis, environmental monitoring and industrial applications. We have measured chloride ions at a carbon paste electrode (CPE) and at a CPE modified with solid AgNO3, a solution of AgNO3 and/or solid silver particles. Detection limits (3 S/N) for chloride ions were 100 μM, 100 μM and 10 μM for solid AgNO3, solution of AgNO3 and/or solid silver particles, respectively. The CPE modified with silver particles is the mo...

  5. Amperometric Sensor for Detection of Chloride Ions

    Directory of Open Access Journals (Sweden)

    Rene Kizek

    2008-09-01

    Full Text Available Chloride ion sensing is important in many fields such as clinical diagnosis, environmental monitoring and industrial applications. We have measured chloride ions at a carbon paste electrode (CPE and at a CPE modified with solid AgNO3, a solution of AgNO3 and/or solid silver particles. Detection limits (3 S/N for chloride ions were 100 μM, 100 μM and 10 μM for solid AgNO3, solution of AgNO3 and/or solid silver particles, respectively. The CPE modified with silver particles is the most sensitive to the presence chloride ions. After that we approached to the miniaturization of the whole electrochemical instrument. Measurements were carried out on miniaturized instrument consisting of a potentiostat with dimensions 35 × 166 × 125 mm, screen printed electrodes, a peristaltic pump and a PC with control software. Under the most suitable experimental conditions (Britton-Robinson buffer, pH 1.8 and working electrode potential 550 mV we estimated the limit of detection (3 S/N as 500 nM.

  6. Determination of the constants of the solubility product of Ln(OH){sub 3} and the effect of the chloride ions on the lanthanum hydrolysis, praseodymium and lutetium in aqueous solutions of ion force 2 Molar; Determinacion de las constantes del producto de solubilidad de Ln(OH){sub 3} y el efecto de los iones cloruro sobre la hidrolisis de lantano, praseodimio y lutecio en soluciones acuosas de fuerza ionica 2 Molar

    Energy Technology Data Exchange (ETDEWEB)

    Lopez G, H.D

    2005-07-01

    The behavior of lanthanum (III), praseodymium (III), and lutetium (III) was studied in 2 M NaClO{sub 4} (aq) and 2 M NaCl (aq) at 303 K and free -CO{sub 2} conditions. Solubility diagrams (p Ln(aq)-pC{sub H}) were obtained by means of a radiochemical method. The pC{sub H} borderlines of saturation and unsaturation zones of the solutions and solubility product constants for Ln(OH){sub 3} were determined from these diagrams. The fitting of the solubility equation to the experimental values of p Ln(aq)-pC{sub H} diagrams allowed the calculation of the first hydrolysis and solubility product constants. Independently, the stability constants for the first species of hydrolysis were determined by means of pH titrations, the data were treated with the program SUPERQUAD and fitted to the mean ligand number equation. The stability constants for the species LnCl{sup 2+} were as well calculated in 2M ionic strength and 303 K from the hydrolysis constant values obtained in both perchlorate and chloride media. The values obtained for La, Pr and Lu were: logK{sub ps}: 21.11 {+-} 0.09, 19.81 {+-} 0.11 and 18.10 {+-} 0.13 in 2M NaClO{sub 4}; logK{sub ps}: 22.22 {+-} 0.09, 21.45 {+-} 0.14 and 18.52 {+-} 0.29 in 2M NaCl; log {beta}{sub 1}: - 8.64 {+-} 0.02, - 8.37 {+-} 0.01 and - 7.95 {+-} 0.11 in 2M NaClO{sub 4}; log {beta}{sub 1}{sup /} : - 9.02 {+-} 0.11, - 8.75 {+-} 0.01 and - 8.12 {+-} 0.03 in 2M NaCl and the values for log {beta}{sub 1,Cl} were - 0.0255, - 0.155 and - 0.758, respectively. (Author)

  7. Stability constants of the Europium complexes with the chloride ions

    International Nuclear Information System (INIS)

    The stability constants of lanthanides complexes with chloride ions which were determined at the same ionic force but in different media, are significantly different. It does not exist a systematic study over these stability constants. The purpose of this work is to determine the stability constants of the europium complexes with chloride ions at 303 K, by the solvents extraction method. (Author)

  8. Polarization and Charge Transfer in the Hydration of Chloride Ions

    OpenAIRE

    Zhao, Zhen; Rogers, David M.; Beck, Thomas L.

    2009-01-01

    A theoretical study of the structural and electronic properties of the chloride ion and water molecules in the first hydration shell is presented. The calculations are performed on an ensemble of configurations obtained from molecular dynamics simulations of a single chloride ion in bulk water. The simulations utilize the polarizable AMOEBA force field for trajectory generation, and MP2-level calculations are performed to examine the electronic structure properties of the ions and surrounding...

  9. Effect of Chloride Type on Penetration of Chloride Ions in Concrete

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The influence of chloride type on the diffusivity of chloride ions in concrete was studied by experiment. The result shows that the glectric resistance of concrete and the chloride diffusion coefficient are influenced by chloride type. For the same water/cement ratio (W/C), the diffusion coefficient D in KCl solution is larger than that in NaCl solution; however, the concrete resistance in KCl solution is smaller than that in NaCl solution. The experimental result is analyzed with theory of diffusion.

  10. Computational modelling of chloride ion transport in reinforced concrete

    OpenAIRE

    Meijers, S.J.H.; Bijen, J.M.J.M.; De Borst, R.; Fraaij, A.L.A.

    2001-01-01

    Exposure to a saline environment is a major threat with respect to the durability of reinforced concrete structures. The chloride ions, which are present in seawater and de-icing salts, are able to penetrate the concrete up to the depth of the reinforcement. They can eventually trigger a pitting corrosion process. The assessment of a corrosion-free service life of concrete structures is of paramount economic interest. However, the modelling of the ingress of chloride ions is complicated due t...

  11. VOCl as a Cathode for Rechargeable Chloride Ion Batteries.

    Science.gov (United States)

    Gao, Ping; Reddy, M Anji; Mu, Xiaoke; Diemant, Thomas; Zhang, Le; Zhao-Karger, Zhirong; Chakravadhanula, Venkata Sai Kiran; Clemens, Oliver; Behm, R Jürgen; Fichtner, Maximilian

    2016-03-18

    A novel room temperature rechargeable battery with VOCl cathode, lithium anode, and chloride ion transporting liquid electrolyte is described. The cell is based on the reversible transfer of chloride ions between the two electrodes. The VOCl cathode delivered an initial discharge capacity of 189 mAh g(-1) . A reversible capacity of 113 mAh g(-1) was retained even after 100 cycles when cycled at a high current density of 522 mA g(-1) . Such high cycling stability was achieved in chloride ion batteries for the first time, demonstrating the practicality of the system beyond a proof of concept model. The electrochemical reaction mechanism of the VOCl electrode in the chloride ion cell was investigated in detail by ex situ X-ray diffraction (XRD), infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The results confirm reversible deintercalation-intercalation of chloride ions in the VOCl electrode. PMID:26924132

  12. Polarization and charge transfer in the hydration of chloride ions

    International Nuclear Information System (INIS)

    A theoretical study of the structural and electronic properties of the chloride ion and water molecules in the first hydration shell is presented. The calculations are performed on an ensemble of configurations obtained from molecular dynamics simulations of a single chloride ion in bulk water. The simulations utilize the polarizable AMOEBA force field for trajectory generation and MP2-level calculations are performed to examine the electronic structure properties of the ions and surrounding waters in the external field of more distant waters. The ChelpG method is employed to explore the effective charges and dipoles on the chloride ions and first-shell waters. The quantum theory of atoms in molecules (QTAIM) is further utilized to examine charge transfer from the anion to surrounding water molecules. The clusters extracted from the AMOEBA simulations exhibit high probabilities of anisotropic solvation for chloride ions in bulk water. From the QTAIM analysis, 0.2 elementary charges are transferred from the ion to the first-shell water molecules. The default AMOEBA model overestimates the average dipole moment magnitude of the ion compared to the quantum mechanical value. The average magnitude of the dipole moment of the water molecules in the first shell treated at the MP2-level, with the more distant waters handled with an AMOEBA effective charge model, is 2.67 D. This value is close to the AMOEBA result for first-shell waters (2.72 D) and is slightly reduced from the bulk AMOEBA value (2.78 D). The magnitude of the dipole moment of the water molecules in the first solvation shell is most strongly affected by the local water-water interactions and hydrogen bonds with the second solvation shell, rather than by interactions with the ion.

  13. Polarization and charge transfer in the hydration of chloride ions

    Science.gov (United States)

    Zhao, Zhen; Rogers, David M.; Beck, Thomas L.

    2010-01-01

    A theoretical study of the structural and electronic properties of the chloride ion and water molecules in the first hydration shell is presented. The calculations are performed on an ensemble of configurations obtained from molecular dynamics simulations of a single chloride ion in bulk water. The simulations utilize the polarizable AMOEBA force field for trajectory generation and MP2-level calculations are performed to examine the electronic structure properties of the ions and surrounding waters in the external field of more distant waters. The ChelpG method is employed to explore the effective charges and dipoles on the chloride ions and first-shell waters. The quantum theory of atoms in molecules (QTAIM) is further utilized to examine charge transfer from the anion to surrounding water molecules. The clusters extracted from the AMOEBA simulations exhibit high probabilities of anisotropic solvation for chloride ions in bulk water. From the QTAIM analysis, 0.2 elementary charges are transferred from the ion to the first-shell water molecules. The default AMOEBA model overestimates the average dipole moment magnitude of the ion compared to the quantum mechanical value. The average magnitude of the dipole moment of the water molecules in the first shell treated at the MP2-level, with the more distant waters handled with an AMOEBA effective charge model, is 2.67 D. This value is close to the AMOEBA result for first-shell waters (2.72 D) and is slightly reduced from the bulk AMOEBA value (2.78 D). The magnitude of the dipole moment of the water molecules in the first solvation shell is most strongly affected by the local water-water interactions and hydrogen bonds with the second solvation shell, rather than by interactions with the ion.

  14. Ion exchange in a zeolite-molten chloride system

    International Nuclear Information System (INIS)

    Electrometallurgical treatment of spent nuclear fuel results in a secondary waste stream of radioactive fission products dissolved in chloride salt. Disposal plans include a waste form that can incorporate chloride forms featuring one or more zeolites consolidated with sintered glass. A candidate method for incorporating fission products in the zeolites is passing the contaminated salt over a zeolite column for ion exchange. To date, the molten chloride ion-exchange properties of four zeolites have been investigated for this process: zeolite A, IE95 reg-sign, clinoptilolite, and mordenite. Of these, zeolite A has been the most promising. Treating zeolite 4A, the sodium form of zeolite A , with the solvent salt for the waste stream-lithium-potassium chloride of eutectic melting composition, is expected to provide a material with favorable ion-exchange properties for the treatment of the waste salt. The authors constructed a pilot-plant system for the ion-exchange column. Initial results indicate that there is a direct relationship between the two operating variable of interest, temperature, and initial sodium concentration. Also, the mass ratio has been about 3--5 to bring the sodium concentration of the effluent below 1 mol%

  15. Disposable sensor for electrochemical determination of chloride ions.

    Science.gov (United States)

    Bujes-Garrido, Julia; Arcos-Martínez, M Julia

    2016-08-01

    This work describes the development of a new, simple and inexpensive method for the determination of chloride ions, by using voltammetric disposable sensors. The sensor includes three screen printed electrodes: a working, an auxiliary (both carbon based paste electrodes), and a pseudo-reference Ag/AgCl paste based electrode. Since the presence of chloride ions in the solution modifies the equilibrium potential of Ag/AgCl electrode, the concentration of this analyte has been determined through the systematic shift of the voltammetric peak potential of a control species such as potassium ferricyanide, potassium ferrocyanide or ferrocenemethanol. These control species can be used in solution or mixed into the carbon paste of the working screen printed electrode. In order to characterize the developed methods, reproducibility, repeatability and detection limit of the sensors were calculated in each case. Reproducibility values below 3% (n=5) were obtained. When ferrocenemethanol was used as control species, the lowest quantity of chloride ions detected was 10.0mM. A comprehensive study of interfering ions was also carried out. These sensors were successfully applied to determine the chloride content in sea water and in a commercial saline solution sample. PMID:27216668

  16. A chronopotentiometric approach for measuring chloride ion concentration

    NARCIS (Netherlands)

    Abbas, Yawar; Olthuis, Wouter; Berg, van den Albert

    2013-01-01

    In this paper, a novel approach is reported for the electrochemical measurement of chloride ions in aqueous solution. This sensor is based on the stimulus/response principle of chronopotentiometry. A current pulse is applied at the Ag/AgCl working electrode and the potential change is measured with

  17. Chloride (Cl-) ion-mediated shape control of palladium nanoparticles

    Science.gov (United States)

    Nalajala, Naresh; Chakraborty, Arup; Bera, Bapi; Neergat, Manoj

    2016-02-01

    The shape control of Pd nanoparticles is investigated using chloride (Cl-) ions as capping agents in an aqueous medium in the temperature range of 60-100 °C. With weakly adsorbing and strongly etching Cl- ions, oxygen plays a crucial role in shape control. The experimental factors considered are the concentration of the capping agents, reaction time and reaction atmosphere. Thus, Pd nanoparticles of various shapes with high selectivity can be synthesized. Moreover, the removal of Cl- ions from the nanoparticle surface is easier than that of Br- ions (moderately adsorbing and etching) and I- ions (strongly adsorbing and weakly etching). The cleaned Cl- ion-mediated shape-controlled Pd nanoparticles are electrochemically characterized and the order of the half-wave potential of the oxygen reduction reaction in oxygen-saturated 0.1 M HClO4 solution is of the same order as that observed with single-crystal Pd surfaces.

  18. CHLORIDE ION PERMEABILITY STUDIES OF METAKAOLIN BASED HIGH PERFORMANCE CONCRETE

    Directory of Open Access Journals (Sweden)

    Dr.Vaishali. G.Ghorpade,

    2011-02-01

    Full Text Available To increase the applications of HPC in India, greater under standing of HPC produced with locally available materials and indigenously produced mineral admixtures is essential. In the present investigation, HPC has been produced with locally available aggregates and metakaolin as the mineral admixture. Various metakaolin based HPC mixes were attained by absolute volume method. Cubes of 150X150X150 mm size were cast and cured for 28 days and then tested for compressive strength. Chloride ion permeability test as per ASTM C 1202 has been conducted on various HPC mixes to measure the permeability values of HPC produced with metakaolin. The experimental results indicate that metakaolin has the ability to considerably reduce the permeability of high performance concrete. The various details about the chloride ion permeability test have been presented in this paper.

  19. Diffusion Decay Coefficient for Chloride Ions of Concrete Containing Mineral Admixtures

    OpenAIRE

    Jae-Im Park; Kwang-Myong Lee; Soon-Oh Kwon; Su-Ho Bae; Sang-Hwa Jung; Sung-Won Yoo

    2016-01-01

    The diffusion coefficient for chloride ions and the diffusion decay coefficient for chloride ions are essential variables for a service life evaluation of concrete structures. They are influenced by water-binder ratio, exposure condition, curing temperature, cement type, and the type and use of mineral admixture. Mineral admixtures such as ground granulated blast furnace slag, fly ash, and silica fume have been increasingly used to improve resistance against chloride ions penetration in concr...

  20. Ion-chromatographic estimation of chloride in colloidal graphite suspension

    International Nuclear Information System (INIS)

    Determination of major, minor and trace constituents in the nuclear fuel and structural materials has always been a fascinating field of advanced analytical chemistry. Till few years ago, most of the routine analytical techniques were based on prior chemical separation procedures followed by conventional classical techniques of analysis like gravimetric and volumetric methods. These conventional methods are very cumbersome and time consuming ones along with the requirement of different suitable complexing agents. Also, these classical methods are not suitable for trace elemental analysis. In the present day context, the requirement of trace level measurements in diversified matrices has become order of the day. The trace levels of measurements to be reported are going from ppm to ppt levels with l increase in confidence levels. In this regard, Ion Chromatographic method of analysis assumes a significant and pivotal role in the field of analytical chemistry. The present paper describes the estimation of chloride in graphite suspension using ion chromatography with its prior separation by pyro-hydrolysis technique. The furnace temperature, heating rate, time of heating, pH of collecting solution and sample weight are optimized to get maximum extractability of chloride from the graphite suspension during pyro-hydrolysis. The instrument was calibrated using synthetically prepared chloride standards in the range of 0.1 μlg/ml to 1.0 μg/ml. A suppressor based Metrohm make 850 professional IC is used for the analysis. A mixture of sodium carbonate and bicarbonate solution is used as eluent. The paper describes the complete experimental details. The values obtained by IC are compared with a spectrophotometric method and the comparison is in good agreement. A RSD of ± 5% has been achieved in IC measurements

  1. Electrochemical chloride ion detection technique by using Pt electrode in high temperature water

    International Nuclear Information System (INIS)

    Chloride ion is a representative chemical species causing the corrosion failure of structural materials. For detecting chloride ions in a high temperature solution, the potentio-dynamic polarization and potential transient technique were performed with a Pt electrode. From the polarization behaviour, it was recognized that there is a potential region forming a stable Pt oxide layer to blockade the oxidation reaction of dissolved hydrogen. Since the presence of chloride ions affect the growth of an oxide layer on the metal surface, the potential transient technique was used to investigate the interference of chloride ions for formation of the Pt oxide layer by repeating apply the potential between oxide-free and oxide forming potentials. As a result, the initial oxidation current of dissolved hydrogen appeared to increase with an increase in the chloride ion concentration of the test solutions, and the time for reaching the limiting oxidation current was delayed. From the oxidation current of dissolved hydrogen, we could detect chloride ions down to 2.8 x 10-5 M in high temperature solutions. Consequently, the oxidation current of dissolved hydrogen could be an indicator of chloride ions, because the formation of the Pt oxide layer is sensitively interfered with the chloride ions. (authors)

  2. A novel capsule-based self-recovery system with a chloride ion trigger

    Science.gov (United States)

    Xiong, Wei; Tang, Jiaoning; Zhu, Guangming; Han, Ningxu; Schlangen, Erik; Dong, Biqin; Wang, Xianfeng; Xing, Feng

    2015-06-01

    Steel is prone to corrosion induced by chloride ions, which is a serious threat to reinforced concrete structures, especially in marine environments. In this work, we report a novel capsule-based self-recovery system that utilizes chloride ions as a trigger. These capsules, which are functionalized via a smart response to chloride ions, are fabricated using a silver alginate hydrogel that disintegrates upon contact with chloride ions, and thereby releases the activated core materials. The experimental results show that the smart capsules respond to a very low concentration of chloride ions (0.1 wt%). Therefore, we believe that this novel capsule-based self-recovery system will exhibit a promising prospect for self-healing or corrosion inhibition applications.

  3. Erratum to: Study on Chloride Ion Penetration Resistance of Rubberized Concrete Under Steady State Condition

    Directory of Open Access Journals (Sweden)

    Md Noor Nurazuwa

    2016-01-01

    In this paper, the effect of crumb rubber, CR as fine aggregate in the concrete to enhance concrete durability against chloride ion diffusion was studied. Chloride ion diffusion in rubberized concrete was tested by migration test under steady state condition. Concrete specimen with water-to-cement ratio of 0.50 was prepared to study the CR effectiveness in comparison with lower water-to-cement ratio. In addition, 10% silica fume, SF was added to provide denser concrete and to understand its effectiveness against chloride ion diffusion. Results showed that chloride transport characteristics were improved by the increasing amount of CR in all mixed due to the fact that CR has the ability to repel water. Meanwhile, rubberized concrete with w/c = 0.35 gave better resistance against chloride ion penetration compared to w/c = 0.50. This was much improved with combination of CR and SF.

  4. Diffusion Decay Coefficient for Chloride Ions of Concrete Containing Mineral Admixtures

    Directory of Open Access Journals (Sweden)

    Jae-Im Park

    2016-01-01

    Full Text Available The diffusion coefficient for chloride ions and the diffusion decay coefficient for chloride ions are essential variables for a service life evaluation of concrete structures. They are influenced by water-binder ratio, exposure condition, curing temperature, cement type, and the type and use of mineral admixture. Mineral admixtures such as ground granulated blast furnace slag, fly ash, and silica fume have been increasingly used to improve resistance against chloride ions penetration in concrete structures built in an offshore environment. However, there is not enough measured data to identify the statistical properties of diffusion decay coefficient for chloride ions in concrete using mineral admixtures. This paper is aimed at evaluating the diffusion decay coefficient for chloride ions of concrete using ordinary Portland cement or blended cement. NT BUILD 492 method, an electrophoresis experiment, was used to measure the diffusion coefficient for chloride ions with ages. It was revealed from the test results that the diffusion decay coefficient for chloride ions was significantly influenced by W/B and the replacement ratio of mineral admixtures.

  5. The Role of Chloride Ions during the Formation of Akaganéite Revisited

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    Johanna Scheck

    2015-11-01

    Full Text Available Iron(III hydrolysis in the presence of chloride ions yields akaganéite, an iron oxyhydroxide mineral with a tunnel structure stabilized by the inclusion of chloride. Yet, the interactions of this anion with the iron oxyhydroxide precursors occurring during the hydrolysis process, as well as its mechanistic role during the formation of a solid phase are debated. Using a potentiometric titration assay in combination with a chloride ion-selective electrode, we have monitored the binding of chloride ions to nascent iron oxyhydroxides. Our results are consistent with earlier studies reporting that chloride ions bind to early occurring iron complexes. In addition, the data suggests that they are displaced with the onset of oxolation. Chloride ions in the akaganéite structure must be considered as remnants from the early stages of precipitation, as they do not influence the basic mechanism, or the kinetics of the hydrolysis reactions. The structure-directing role of chloride is based upon the early stages of the reaction. The presence of chloride in the tunnel-structure of akagenéite is due to a relatively strong binding to the earliest iron oxyhydroxide precursors, whereas it plays a rather passive role during the later stages of precipitation.

  6. Influence of chloride ions on actinide chemistry. Effects of radiolysis and temperature

    International Nuclear Information System (INIS)

    This research thesis addresses the chemistry of radionuclides in natural waters, an issue which is related to the management of long life radioactive wastes. Chloride ions are the most concentrated ions but their weak complexing power explains the fact that they are often neglected in speciation calculations. The objective of this research is to identify the influence of chloride ions on transuranium elements (Np, Pu and Am). Their influence is investigated with respect to chemical conditions close to that of underground waters and for concentrated media related to storage conditions in saline media. The author discusses media-related corrections applied to thermodynamic functions, reports a bibliographic study on the stability of actinide chloride complexes, reports a spectrophotometric investigation of complexation by chlorides, and reports the study of the influence of chlorides in a carbonate medium (solubility of americium at different temperatures, and notably at room temperature)

  7. The development of chloride ion selective polypyrrole thin film on a layer-by-layer carbon nanotube working electrode

    Science.gov (United States)

    Liu, Yang; Lynch, Jerome

    2011-04-01

    A chloride ion selective thin film sensor is proposed for measuring chloride ion concentration, which is an environmental parameter correlated to corrosion. In this work, electrochemical polymerization of Polypyrrole (PPy) doped with chloride ions was achieved on the top of a carbon nanotube (CNT) thin film as a working electrode in an electrochemical cell. The underlying CNT layer conjugated with doped PPy thin film can form a multifunctional "selfsensing" material platform for chloride ion detection in a concrete environment. The paper presents the first type of work using CNT and PPy as hybrid materials for chloride ion sensing. Electrochemical polymerization of PPy results in oxidation that yields an average of one positive charge distributed over four pyrrole units. This positive charge is compensated by negatively-charged chloride ions in the supporting electrolyte. In effect, the chloride ion-doped PPy has become molecularly imprinted with chloride ions thereby providing it with some degree of perm-selectivity for chloride ions. The detection limit of the fabricated chloride ion-doped PPy thin film can reach 10-8 M and selectivity coefficients are comparable to those in the literature. The reported work aims to lay a strong foundation for detecting chloride ion concentrations in the concrete environment.

  8. Structural Mechanism for Light-driven Transport by a New Type of Chloride Ion Pump, Nonlabens marinus Rhodopsin-3.

    Science.gov (United States)

    Hosaka, Toshiaki; Yoshizawa, Susumu; Nakajima, Yu; Ohsawa, Noboru; Hato, Masakatsu; DeLong, Edward F; Kogure, Kazuhiro; Yokoyama, Shigeyuki; Kimura-Someya, Tomomi; Iwasaki, Wataru; Shirouzu, Mikako

    2016-08-19

    The light-driven inward chloride ion-pumping rhodopsin Nonlabens marinus rhodopsin-3 (NM-R3), from a marine flavobacterium, belongs to a phylogenetic lineage distinct from the halorhodopsins known as archaeal inward chloride ion-pumping rhodopsins. NM-R3 and halorhodopsin have distinct motif sequences that are important for chloride ion binding and transport. In this study, we present the crystal structure of a new type of light-driven chloride ion pump, NM-R3, at 1.58 Å resolution. The structure revealed the chloride ion translocation pathway and showed that a single chloride ion resides near the Schiff base. The overall structure, chloride ion-binding site, and translocation pathway of NM-R3 are different from those of halorhodopsin. Unexpectedly, this NM-R3 structure is similar to the crystal structure of the light-driven outward sodium ion pump, Krokinobacter eikastus rhodopsin 2. Structural and mutational analyses of NM-R3 revealed that most of the important amino acid residues for chloride ion pumping exist in the ion influx region, located on the extracellular side of NM-R3. In contrast, on the opposite side, the cytoplasmic regions of K. eikastus rhodopsin 2 were reportedly important for sodium ion pumping. These results provide new insight into ion selection mechanisms in ion pumping rhodopsins, in which the ion influx regions of both the inward and outward pumps are important for their ion selectivities. PMID:27365396

  9. Changes in acceleration rate of chloride ions depending on climatic conditions. Influence of rain

    International Nuclear Information System (INIS)

    Mild steel,copper and aluminum samples were exposed outdoors in two atmospheric test stations located in Havana, Cuba and Medellin, colombia. Two parallel group of samples were formed, one for each station. They were submitted to accelerated outdoor test by intermittent spraying of a salt solution (SCAB test) according to ISO 11474.98, receiving also the influence of the open atmosphere. The acceleration of corrosion rate of the three metals caused by the presence of chloride ions in both stations was determined. As expected, steel shows the higher corrosion rate and acceleration by chlorides, particularly at Cuban corrosion station. A remarkable difference in the acceleration rate of chloride ions for mild steel and copper between Cuban and Colombian acceleration rate of chloride ions of steel and copper. Steel corrosion products were analysed by Moessbauer Spectroscopy. Water absorption was also studied. The presence of magnetite, goethite and other Iron compounds was determined. (Author) 10 refs

  10. Inhibition of Chloride Induced Crevice Corrosion in Alloy 22 by Fluoride Ions

    Energy Technology Data Exchange (ETDEWEB)

    Carranza, R M; Rodr?guez, M A; Rebak, R B

    2005-10-09

    Alloy 22 (N06022) is highly resistant to localized corrosion. Alloy 22 may be susceptible to crevice corrosion in pure chloride (Cl{sup -}) solutions under aggressive environmental conditions. The effect of the fluoride (F{sup -}) over the crevice corrosion induced by chloride ions is still not well established. The objective of the present work was to explore the crevice corrosion resistance of this alloy to different mixtures of fluorides and chlorides. Cyclic potentiodynamic polarization (CPP) tests were conducted in deaerated aqueous solutions of pure halide ions and also in different mixtures of chloride and fluoride at 90 C and pH 6. The range of chloride concentration [Cl{sup -}] was 0.001 M {le} [Cl{sup -}] {le} 1 M and the range of molar fluoride to chloride ratio [F{sup -}]/[Cl{sup -}] was 0.1 {le} [F{sup -}]/[Cl{sup -}] {le} 10. Results showed that Alloy 22 was susceptible to crevice corrosion in all the pure chloride solutions but not in the pure fluoride solutions. Fluoride ions showed an inhibitor behavior only in mixtures with a molar ratio [F{sup -}]/[Cl{sup -}] > 2. For mixtures with a molar ratio [F{sup -}]/[Cl{sup -}] of 7 and 10 the inhibition of crevice corrosion was complete.

  11. Evaluating capacitive deionization for water desalination by direct determination of chloride ions

    OpenAIRE

    Díaz Baizán, Patricia; González Arias, Zoraida; Granda Ferreira, Marcos; Menéndez López, Rosa María; Santamaría Ramírez, Ricardo; Blanco Rodríguez, Clara

    2014-01-01

    Ionic conductivity and capacitance measurements are widely used methods for evaluating the desalination efficiency in capacity deionization processes. In this study, these methods are revised and several problems associated to them are identified and evaluated. Furthermore, a new method based on the determination of the chloride ion concentration by means of a chloride selective electrode is proposed as a more reliable alternative for evaluating the desalination performance in these systems. ...

  12. Activation energy of self-diffusion of zinc, chloride and chromate ions

    International Nuclear Information System (INIS)

    Theoretical activation energy of self-diffusion of zinc, chloride and chromate ions was computed on the basis of the Onsager and Arrhenius equations. These values are compared with those determined experimentally for the self-diffusion of Zn(sup(2+) ions in the present work as well as previously reported values for self-diffusion of Clsup(-) and CrOsub(4)sup(2-) ions. A reasonably good agreement is observed between the two values. (author)

  13. Synthetic ion transporters can induce apoptosis by facilitating chloride anion transport into cells

    Science.gov (United States)

    Ko, Sung-Kyun; Kim, Sung Kuk; Share, Andrew; Lynch, Vincent M.; Park, Jinhong; Namkung, Wan; van Rossom, Wim; Busschaert, Nathalie; Gale, Philip A.; Sessler, Jonathan L.; Shin, Injae

    2014-10-01

    Anion transporters based on small molecules have received attention as therapeutic agents because of their potential to disrupt cellular ion homeostasis. However, a direct correlation between a change in cellular chloride anion concentration and cytotoxicity has not been established for synthetic ion carriers. Here we show that two pyridine diamide-strapped calix[4]pyrroles induce coupled chloride anion and sodium cation transport in both liposomal models and cells, and promote cell death by increasing intracellular chloride and sodium ion concentrations. Removing either ion from the extracellular media or blocking natural sodium channels with amiloride prevents this effect. Cell experiments show that the ion transporters induce the sodium chloride influx, which leads to an increased concentration of reactive oxygen species, release of cytochrome c from the mitochondria and apoptosis via caspase activation. However, they do not activate the caspase-independent apoptotic pathway associated with the apoptosis-inducing factor. Ion transporters, therefore, represent an attractive approach for regulating cellular processes that are normally controlled tightly by homeostasis.

  14. Sulfate radical-based degradation of polychlorinated biphenyls: Effects of chloride ion and reaction kinetics

    International Nuclear Information System (INIS)

    Highlights: ► A kinetic model was used to predict the radical species and their distributions. ► The generated radical species were identified by EPR. ► The second-order rate constants of sulfate radical with PCBs were determined. - Abstract: Advanced oxidation processes (AOPs) based on sulfate radical (SO4·−) have been recently used for soil and groundwater remediation. The presence of chloride ion in natural or wastewater decreases the reactivity of sulfate radical system, but explanations for this behavior were inconsistent, and the mechanisms are poorly understood. Therefore, in this paper we investigated the effect of chloride ion on the degradation of 2,4,4′-CB (PCB28) and biphenyl (BP) by persulfate, based on the produced SO4·−. The results showed that the presence of chloride ion greatly inhibited the transformation of PCB28 and BP. Transformation intermediates of BP were monitored, suggesting that the chloride ion can react with SO4·− to produce chlorine radical, which reacts with BP to generate chlorinated compounds. To better understand the underlying mechanisms of these processes, a kinetic model was developed for predicting the effect of chloride ion on the types of radical species and their distributions. The results showed that chloride ion could influence the selectivity of radical species and their distribution, and increase the concentration of the sum of radical species. In addition, the second-order rate constants of sulfate radical with PCBs were determined, and quantum-chemical descriptors were introduced to predict the rate constants of other PCBs based on our experimental data.

  15. Concrete Durability. Influence of chloride ions concentrations in mixing water and dissolution

    Directory of Open Access Journals (Sweden)

    López Villarino, Begoña

    1995-03-01

    Full Text Available The most aggressive situation which is responsible for most of the cases of steel reinforcement corrosion in concrete, takes place when chlorides are present in the environment. These chlorides destroy the passivating film of steel and promote the denominated pitting corrosion. In order to study the demonstrated corrosive action of chloride ions on concrete structures, a number of experiments have been designed, to quantify the effect of different amounts of this ion in concrete. Several mixes have been prepared with portland cement type II-C-35 to which it has been added, as an additive in mixing water, NaCl in increasing concentrations. The samples obtained were submerged in different dissolutions of NaCl. From the results obtained it is clear that the chloride content in mixing water does not affect the flux of calcium ions; however, its influence on the flux of chloride ions is significant. Likewise, it is confirmed that the existence of chloride ions in dissolution influences the migration of calcium and chloride ions.

    La situación más agresiva, y la responsable del mayor número de casos de corrosión de armaduras en el hormigón, se da cuando en el ambiente hay presencia de cloruros, pues éstos destruyen de forma puntual la capa pasivante del acero, lo que provoca la denominada corrosión por picaduras. Con objeto de estudiar la demostrada acción perniciosa de los cloruros sobre las estructuras de hormigón, se ha diseñado un conjunto de ensayos con el fin de cuantificar el efecto de las distintas cantidades de este ion en la masa de hormigón. Se han realizado diversas amasadas con cemento tipo II-C-35 a las que se añadió, como aditivo en el agua de amasado, NaCl en concentraciones crecientes. Las probetas obtenidas se sumergieron en disoluciones de NaCl de distintas concentraciones. De los resultados obtenidos se deduce que la presencia de cloruros en el agua de amasado no afecta al flujo de iones cálcicos, mientras

  16. Analysis of Chloride Ion Penetration for NPP Concrete Structures by Crack

    International Nuclear Information System (INIS)

    One of the most important deterioration mechanisms of NPP concrete structure is that caused by the chloride penetration of the cement matrix through concrete crack. The main problems caused by chloride penetration in concrete by crack are the lowering of durability and reduction of life due to the corrosion of tensile steel reinforcement in concrete rather than the chemical deterioration of concrete itself. Such problems related to the corrosion of steel reinforcement in concrete occur when a concrete structure is directly exposed to chloride ions through a marine environment or deicers. In addition, problems can arise, in the case of an underground facility (such as the radioactive waste disposal facility of a nuclear power plant), when seawater flows into the groundwater, causing chloride penetration in the concrete structure

  17. Effect of different ions on the anodic behaviour of alloy 800 chloride solutions at high temperature

    International Nuclear Information System (INIS)

    The anodic behaviour and passivity breakdown of alloy 800 in sodium bicarbonate and sodium phosphate aqueous solutions were studied in the temperature range from 100 degrees C to 280 degrees C by means of electrochemical techniques. The effect of phosphate or bicarbonate additions on the pitting susceptibility and pitting morphology of the alloy in chloride solutions was also examined. Experiments were performed in the following solutions: 0.1M NaHCO3, at 100 degrees C, 200 degrees C, 280 degrees C; 0.06M NaH2PO4 + 0.04M Na2HPO4, at 100 degrees C, 200 degrees C and 280 degrees C, and 0.1M NaCl with different additions of bicarbonate ion (0.02M, 0.05M and 0.1M) and phosphate ion (0.01M, 0.05M and 0.1M) at 100 degrees C and 280 degrees C. The anodic polarization curves of alloy 800 in deaerated 0.1M NaHCO3 and 0.06M NaH2PO4 + 0.04M Na2HPO4 solutions exhibited a similar shape at all the tested temperatures. No localized or generalized corrosion was detected on the metallic surface after polarization. The results obtained in chloride plus bicarbonate and chloride plus phosphate mixtures showed that the pitting potential of alloy 800 in chloride solutions was increased by the presence of bicarbonate or phosphate ions. In those solutions where the inhibitor concentration in the mixture is equal or higher than the chloride concentration , the behaviour of the alloy is similar to the one observed in the absence of chlorides. Changes in pitting morphology were found in phosphate containing solutions, while the pits found in bicarbonate containing solutions were similar to those formed in pure chloride solutions. (author). 3 refs., 4 figs

  18. Ion Transport and Microstructure of Sandwich Cementitious Materials Exposed to Chloride Environment

    Institute of Scientific and Technical Information of China (English)

    WANG Xingang; WANG Kai; WANG Rui; XIE Tao; HUANG Jie

    2015-01-01

    Ion transport of sandwich cementitious materials (SCM) exposed to chloride environment was investigated by accelerated diffusion method and natural diffusion method. Pore structure and micromorphology of SCM were investigated by MIP and SEM-EDS. In comparison with the monolayer structural high performance concrete (HPC), conductive charge for 6 hours, chloride diffusion coefficient, and apparent chloride diffusion coefifcient of SCM were decreased by 30%-40%, two orders of magnitude and 40%-50%, respectively. Pore structure of ultra low ion permeability cementitious materials (ULIPCM) prepared for the facesheet is superior to that of HPC prepared for the core. As for porosity, the most probable pore radius, the content of pores with radius 50 nm and the surface area of pores, the order is ULIPCM

  19. Elucidating the structure of the magnesium aluminum chloride complex electrolyte for magnesium-ion batteries

    OpenAIRE

    Canepa, Pieremanuele; Jayaraman, Saivenkataraman; Cheng, Lei; Rajput, Nav Nidhi; Richards, William D.; Gautam, Gopalakrishnan Sai; Curtiss, Larry A.; Persson, Kristin A.; Ceder, Gerbrand

    2015-01-01

    Non-aqueous Mg-ion batteries offer a promising way to overcome safety, costs, and energy density limitations of state-of-the-art Li-ion battery technology. We present a rigorous analysis of the magnesium aluminum chloride complex (MACC) in tetrahydrofuran (THF), one of the few electrolytes that can reversibly plate and strip Mg. We use ab initio calculations and classical molecular dynamics simulations to interrogate the MACC electrolyte composition with the goal of addressing two urgent ques...

  20. Durability of sea-sand containing concrete: Effects of chloride ion penetration

    Institute of Scientific and Technical Information of China (English)

    Yin Huiguang; Li Yan; Lv Henglin; Gao Quan

    2011-01-01

    This paper describes an orthogonal experiment on the effect of water/cement ratio, water consumptionper cubic meter, curing time, and type of sand on the response "resistance to chloride ion penetration".A sea-sand containing concrete was used for the trials. An analysis of chloride ion diffusion coefficients at different factor levels was performed. A predictive model of chloride ion diffusion in concrete is developed through regression analysis. The experimental results show that when the water/cement ratio varies from 0.45 to 0.60, and the water consumption per cubic meter varies from 185 to 215 kg. and the curing time varies from 30 to 180 d then the size of the effects fall in the order (most significant first):curing time, type of sand, water consumption per cubic meter, and water/cement ratio. Chloride ion penetration is reduced, and better durability of the concrete is observed, with longer curing times, less water consumption per cubic meter, and a smaller water/cement ratio.

  1. Studies on Ion-molecule Reaction of Disubstituted Benzene with IonSystem of Acetyl Chloride in Gas Phase

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The ion-molecule reactions of disubstituted benzenes with the ion system of acetyl chloride under the chemical ionization condition were examined and the fragmentation reactions of the adduct ions formed by the ion-molecule reactions were studied by using collision-induced dissocia tion technique. It was found that the electron-releasing groups favored the adduct reactions and the electron-withdrawing groups did not. The position and properties of substituting groups had an effect on the relative abundance of the adduct ions. The fragmentation reaction of the adduct ions formed by ortho-benzene diamine with the acetyl ion was similar to the reductive alkylation reaction of amine in condensed phase.

  2. Chloride ion-dependent surface-enhanced Raman scattering study of biotin on the silver surface

    International Nuclear Information System (INIS)

    In the present paper, the surface enhanced Raman scattering (SERS) technique was employed to study the SERS spectra of biotin molecules formed on the silver surface. The adsorption geometries of biotin molecules on the silver surface were analyzed based on the SERS data. It can be found that most vibration modes show a Raman shift in silver sol after the addition of sodium chloride solution. In addition, The Raman signals of biotin become weaker and weaker with the increase of the concentration of sodium chloride. This may be due to that the interaction between chloride ions and silver particles is stronger than the interaction between biotin molecules and silver particles. When the concentration of sodium chloride in silver colloid is higher than 0.05mol/L, superfluous chloride ions may form an absorption layer so that biotin can not be adsorbed on silver surface directly. The changes in intensity and profile shape in the SERS spectra suggest different adsorption behavior and surface-coverage of biotin on silver surface. The SERS spectra of biotin suggest that the contribution of the charge transfer mechanism to SERS may be dominant.

  3. Allosteric modulation of metabotropic glutamate receptors by chloride ions.

    Science.gov (United States)

    Tora, Amélie S; Rovira, Xavier; Dione, Ibrahima; Bertrand, Hugues-Olivier; Brabet, Isabelle; De Koninck, Yves; Doyon, Nicolas; Pin, Jean-Philippe; Acher, Francine; Goudet, Cyril

    2015-10-01

    Metabotropic glutamate receptors (mGluRs) play key roles in the modulation of many synapses. Chloride (Cl(-)) is known to directly bind and regulate the function of different actors of neuronal activity, and several studies have pointed to the possible modulation of mGluRs by Cl(-). Herein, we demonstrate that Cl(-) behaves as a positive allosteric modulator of mGluRs. For example, whereas glutamate potency was 3.08 ± 0.33 μM on metabotropic glutamate (mGlu) 4 receptors in high-Cl(-) buffer, signaling activity was almost abolished in low Cl(-) in cell-based assays. Cl(-) potency was 78.6 ± 3.5 mM. Cl(-) possesses a high positive cooperativity with glutamate (Hill slope ≈6 on mGlu4), meaning that small variations in [Cl(-)] lead to large variations in glutamate action. Using molecular modeling and mutagenesis, we have identified 2 well-conserved Cl(-) binding pockets in the extracellular domain of mGluRs. Moreover, modeling of activity-dependent Cl(-) variations at GABAergic synapses suggests that these variations may be compatible with a dynamic modulation of the most sensitive mGluRs present in these synapses. Taken together, these data reveal a necessary role of Cl(-) for the glutamate activation of many mGluRs. Exploiting Cl(-) binding pockets may yield to the development of innovative regulators of mGluR activity. PMID:26116702

  4. Determination of fluoride and chloride content in UO2 powder by selective ion electrode potentiometry method using pyrohydrolitic techniques

    International Nuclear Information System (INIS)

    The flouride and chloride ions in uranium oxide powder should be determined since they influence the performance of fuel element during irradiation in the reactor. Determination of flouride and chloride ion content had been done by selective ion electrode Potentiometry method from uranium oxide after separation from U using method pyrohydrolitic. The experiment showed that the maximum efficiencies of the pyrohydrolitic separation of flouride and chloride ions is 93.78±5.51 % and 95.71±3.08 %, with minimum detection of 0.019 ppm and 1.775 ppm respectively. Uranium matrix as much as 250 ppm showed significant influence on the measurement. (author)

  5. Effect of temperature, chloride ions and sulfide ions on the electrochemical properties of 316L stainless steel in simulated cooling water

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The influence of temperature, chloride ions and sulfide ions on the anticorrosion behavior of 316L stainless steel in simulated cooling water was studied by electrochemical impedance spectroscopy and anodic polarization curves. The results show that the film resistance increases with the solution temperature but decreases after 8 days' immersion, which indicates that the film formed at higher temperature has inferior anticorrosion behavior; Chloride ions and sulfide ions have remarkable effects on the elect...

  6. Stability constants of the Europium complexes with the chloride ions; Constantes de estabilidad de los complejos del europio con los iones cloruro

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez R, M.; Solache R, M.; Rojas H, A. [Instituto Nacional de Investigaciones Nucleares, Departamento de Quimica, A.P. 18-1027, C.P. 11801 Mexico D.F. (Mexico)

    2000-07-01

    The stability constants of lanthanides complexes with chloride ions which were determined at the same ionic force but in different media, are significantly different. It does not exist a systematic study over these stability constants. The purpose of this work is to determine the stability constants of the europium complexes with chloride ions at 303 K, by the solvents extraction method. (Author)

  7. Effect of chloride ions on the corrosion and electrochemical behavior of titanium in neutral solutions

    Energy Technology Data Exchange (ETDEWEB)

    Mandzhgaladze, S.N. (Inst. of Metallurgy, Tbilisi, USSR); Mikaberidze, M.P.; Pirtskhalava, D.N.; Vasil' ev, Yu.B.; Bagotskii, V.S.

    1976-01-01

    A solution of NaCl was buffered with a phosphate buffer, and the potential was measured relative to a saturated silver chloride electrode. Polarization curves for cathodically reduced and oxidized titanium are shown, as well as the effect of NaCl concentration on the corrosion current, the steady-state corrosion potential, the cathodic currents, and the anodic currents for cathodically reduced and anodically oxidized titanium. The corrosion potential for oxidized titanium is strongly shifted in the positive direction, and the corrosion current and the dissolution current in the passive state are almost 10 times higher than for prereduced titanium. The different effects of the chloride ions on the rates of the cathode and anode processes result in a practically constant corrosion current for cathodically reduced titanium when c/sub Cl/sup -// less than 5 N. In the case of the oxidized titanium surface, the simultaneous increase in the rate of both the cathode and the anode process with increasing chloride ion concentration results in the increase of the corrosion current proportional to a fractional power of the bulk chloride ion concentration. 2 figures. (RWR)

  8. The study of method of removing chloride ion in the solution of MIPR (medical isotopes production reactor)

    International Nuclear Information System (INIS)

    By prepare the silver impregnated alumina adsorbents under the different ignition temperature to research and explore its capacity of remove chloride ions in this article. The result show the adsorbent can remove chloride ion effectively under the conditions of neutral at 700 degree C. And study the adsorbents' capacity of remove chloride ions and silver ions in nitric acid system. The result show that on 0.02 mol/L nitrate system the effect of Dechlorination column to remove the chloride ions is the best, and in the uranium samples in addition to the simulation the effect of in addition to Yinzhu to remove the silver ions is very good, almost all removed. (authors)

  9. Study of chloride ion transport of composite by using cement and starch as a binder

    Science.gov (United States)

    Armynah, Bidayatul; Halide, Halmar; Zahrawani, Reski, Nurhadi; Tahir, Dahlang

    2016-03-01

    This study presents the chemical bonding and the structural properties of composites from accelerator chloride test migration (ACTM). The volume fractions between binder (cement and starch) and charcoal in composites are 20:80 and 60:40. The effect of the binder to the chemical composition, chemical bonding, and structural properties before and after chloride ion passing through the composites was determined by X-ray fluorescence (XRF), by Fourier transform infra-red (FTIR), and x-ray diffraction (XRD), respectively. From the XRD data, XRF data, and the FTIR data shows the amount of chemical composition, the type of binding, and the structure of composites are depending on the type of binder. The amount of chloride migration using starch as binder is higher than that of cement as a binder due to the density effects.

  10. Bioleaching in brackish waters--effect of chloride ions on the acidophile population and proteomes of model species.

    Science.gov (United States)

    Zammit, Carla M; Mangold, Stefanie; Jonna, Venkateswara rao; Mutch, Lesley A; Watling, Helen R; Dopson, Mark; Watkin, Elizabeth L J

    2012-01-01

    High concentrations of chloride ions inhibit the growth of acidophilic microorganisms used in biomining, a problem particularly relevant to Western Australian and Chilean biomining operations. Despite this, little is known about the mechanisms acidophiles adopt in order to tolerate high chloride ion concentrations. This study aimed to investigate the impact of increasing concentrations of chloride ions on the population dynamics of a mixed culture during pyrite bioleaching and apply proteomics to elucidate how two species from this mixed culture alter their proteomes under chloride stress. A mixture consisting of well-known biomining microorganisms and an enrichment culture obtained from an acidic saline drain were tested for their ability to bioleach pyrite in the presence of 0, 3.5, 7, and 20 g L(-1) NaCl. Microorganisms from the enrichment culture were found to out-compete the known biomining microorganisms, independent of the chloride ion concentration. The proteomes of the Gram-positive acidophile Acidimicrobium ferrooxidans and the Gram-negative acidophile Acidithiobacillus caldus grown in the presence or absence of chloride ions were investigated. Analysis of differential expression showed that acidophilic microorganisms adopted several changes in their proteomes in the presence of chloride ions, suggesting the following strategies to combat the NaCl stress: adaptation of the cell membrane, the accumulation of amino acids possibly as a form of osmoprotectant, and the expression of a YceI family protein involved in acid and osmotic-related stress. PMID:22124722

  11. A Microfluidic Long-Period Fiber Grating Sensor Platform for Chloride Ion Concentration Measurement

    Directory of Open Access Journals (Sweden)

    Jian-Neng Wang

    2011-09-01

    Full Text Available Optical fiber sensors based on waveguide technology are promising and attractive in chemical, biotechnological, agronomy, and civil engineering applications. A microfluidic system equipped with a long-period fiber grating (LPFG capable of measuring chloride ion concentrations of several sample materials is presented. The LPFG-based microfluidic platform was shown to be effective in sensing very small quantities of samples and its transmitted light signal could easily be used as a measurand. The investigated sample materials included reverse osmosis (RO water, tap water, dilute aqueous sample of sea sand soaked in RO water, aqueous sample of sea sand soaked in RO water, dilute seawater, and seawater. By employing additionally a chloride ion-selective electrode sensor for the calibration of chloride-ion concentration, a useful correlation (R2 = 0.975 was found between the separately-measured chloride concentration and the light intensity transmitted through the LPFG at a wavelength of 1,550 nm. Experimental results show that the sensitivity of the LPFG sensor by light intensity interrogation was determined to be 5.0 × 10−6 mW/mg/L for chloride ion concentrations below 2,400 mg/L. The results obtained from the analysis of data variations in time-series measurements for all sample materials show that standard deviations of output power were relatively small and found in the range of 7.413 × 10−5–2.769 × 10−3 mW. In addition, a fairly small coefficients of variations were also obtained, which were in the range of 0.03%–1.29% and decreased with the decrease of chloride ion concentrations of sample materials. Moreover, the analysis of stability performance of the LPFG sensor indicated that the random walk coefficient decreased with the increase of the chloride ion concentration, illustrating that measurement stability using the microfluidic platform was capable of measuring transmitted optical power with accuracy in the range of −0

  12. Anodic behaviour of the stainless steel AISI 430 in aqueous solutions of chloride and sulphate ions

    International Nuclear Information System (INIS)

    The kinetics of the dissolution of stainless steel AISI 430 in the presence of chloride and sulphate ions has been studied in terms of the ion concentration, the pH variation, and the velocity of the working electrode. The experimental method utilized was the potentiostatic anodic polarization, and the reactants used were NaCl and Na2 SO4 at room temperature. Atomic Absorption spectrophotometry and Auger Electrons spectroscopy (AES) analyses were made in order to support the interpretation of results obtained by means of the potentiostatic polarization method. (author)

  13. 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.

  14. Measurement of chloride-ion concentration with long-period grating technology

    Science.gov (United States)

    Tang, Jaw-Luen; Wang, Jian-Neng

    2007-06-01

    A simple and low-cost long-period fiber grating (LPG) sensor suited for chloride-ion concentration measurement is presented. The LPG sensor is found to be sensitive to the refractive index of the medium around the cladding surface of the sensing grating, thus offering the prospect of development of practical sensors such as an ambient index sensor or a chemical concentration indicator with high stability and reliability. We measured chloride ions in a typical concrete sample immersed in salt water solutions with different weight concentrations ranging from 0% to 25%. Results show that the LPG sensor exhibited a linear decrease in the transmission loss and resonance wavelength shift when the concentration increased. The measurement accuracy for the concentration of salt in water solution is estimated to be 0.6% and the limit of detection for chloride ions is about 0.04%. To further enhance its sensitivity for chloride concentrations, we coated a monolayer of colloidal gold nanoparticles as the active material on the grating surface of the LPG sensor. The operating principle of sensing is based on the sensitivity of localized surface plasmon resonance of self-assembled gold colloids on the grating section of the LPG. With this method, a factor of two increase in the sensitivity of detecting chemical solution concentrations was obtained. The advantages of this type of fiber-optic sensor are that it is compact, relatively simple to construct and easy to use. Moreover, the sensor has the potential capability for on-site, in vivo and remote sensing, and it has potential use as a disposable sensor.

  15. Individual and combined effects of chloride, sulfate, and magnesium ions on hydrated Portland-cement paste

    International Nuclear Information System (INIS)

    Ground water with a high concentration of magnesium ion is known to cause deterioration to portland cement concretes. A proposed mechanism for this deterioration process published previously involves an approximate 1:1 replacement of Ca ions by Mg ions in the crystalline phases of hydrated cement. The current study was undertaken to determine which ions, among magnesium, chloride, and sulfate, cause deterioration; whether their deleterious action is individual or interdependent; and to relate this mechanism of deterioration to the outlook for a 100-yr service life of concretes used in mass placements at the Waste Isolation Pilot Plant. Loss of Ca ion by cement pastes was found to be strongly related to the concentration of Mg ion in simulated ground-water solutions in which the paste samples were aged. This was true of both salt- containing and conventional cement pastes. No other ion in the solutions exerted a strong effect on Ca loss. Ca ion left first from calcium hydroxide in the pastes, depleting all calcium hydroxide by 60 days. Some calcium silicate hydrate remained even after 90 days in the solutions with the highest concentration of Mg ion, while the paste samples deteriorated noticeably. The results indicated a mechanism that involves dissolution of Ca phases and transport of Ca ions to the surface of the sample, followed by formation of Mg-bearing phases at this reaction surface rather than directly by substitution within the microstructure of hydrated cement. Given that calcium hydroxide and calcium silicate hydrate are the principal strength-giving phases of hydrated cement, this mechanism indicates the likelihood of significant loss of integrity of a concrete exposed to Mg-bearing ground water at the WIPP. The rate of deterioration ultimately will depend on Mg-ion concentration, the microstructure materials of the concrete exposed to that groundwater, and the availability of brine

  16. Determination of chloride in brazilian crude oils by ion chromatography after extraction induced by emulsion breaking.

    Science.gov (United States)

    Robaina, Nicolle F; Feiteira, Fernanda N; Cassella, Alessandra R; Cassella, Ricardo J

    2016-08-01

    The present paper reports on the development of a novel extraction induced by emulsion breaking (EIEB) method for the determination of chloride in crude oils. The proposed method was based on the formation and breaking of oil-in-water emulsions with the samples and the consequential transference of the highly water-soluble chloride to the aqueous phase during emulsion breaking, which was achieved by centrifugation. The determination of chloride in the extracts was performed by ion chromatography (IC) with conductivity detection. Several parameters (oil phase:aqueous phase ratio, crude oil:mineral oil ratio, shaking time and type and concentration of surfactant) that could affect the performance of the method were evaluated. Total extraction of chloride from samples could be achieved when 1.0g of oil phase (0.5g of sample+0.5g of mineral oil) was emulsified in 5mL of a 2.5% (m/v) solution of Triton X-114. The obtained emulsion was shaken for 60min and broken by centrifugation for 5min at 5000rpm. The separated aqueous phase was collected, filtered and diluted before analysis by IC. Under these conditions, the limit of detection was 0.5μgg(-1) NaCl and the limit of quantification was 1.6μgg(-1) NaCl. We applied the method to the determination of chloride in six Brazilian crude oils and the results did not differ statistically from those obtained by the ASTM D6470 method when the paired Student-t-test, at 95% confidence level, was applied. PMID:27388656

  17. Potential energy, force distribution and oscillatory motion of chloride ion inside electrically charged carbon nanotubes

    Science.gov (United States)

    Sadeghi, F.; Ansari, R.; Darvizeh, M.

    2016-06-01

    In this research, a continuum-based model is presented to explore potential energy, force distribution and oscillatory motion of ions, and in particular chloride ion, inside carbon nanotubes (CNTs) decorated by functional groups at two ends. To perform this, van der Waals (vdW) interactions between ion and nanotube are modeled by the 6-12 Lennard-Jones (LJ) potential, whereas the electrostatic interactions between ion and functional groups are modeled by the Coulomb potential and the total interactions are analytically derived by summing the vdW and electrostatic interactions. Making the assumption that carbon atoms and charge of functional groups are all uniformly distributed over the nanotube surface and the two ends of nanotube, respectively, a continuum approach is utilized to evaluate the related interactions. Based on the actual force distribution, the equation of motion is also solved numerically to arrive at the time history of displacement and velocity of inner core. With respect to the proposed formulations, comprehensive studies on the variations of potential energy and force distribution are carried out by varying functional group charge and nanotube length. Moreover, the effects of these parameters together with initial conditions on the oscillatory behavior of system are studied and discussed in detail. It is found out that chloride ion escapes more easily from negatively charged CNTs which is followed by uncharged and positively charged ones. It is further shown that the presence of functional groups leads to enhancing the operating frequency of such oscillatory systems especially when the electric charges of ion and functional groups have different signs.

  18. Diffusion of Chloride Ions in Soils:Ⅱ.Kinetic and Ther—modynamic Characteristics

    Institute of Scientific and Technical Information of China (English)

    XUMINGGANG; ZHANGYIPING; 等

    1997-01-01

    The amounts of chloride ions diffused in four soils of different textures at the same water content under different temperature and at varied time were measured by the diffusion cell method using 36Cl-labelled CaCl2 solution,Five kinetic models were used to fit the dynamic process of the diffusion of chloride ions in the soils ,It was found that Elovich equation or power function equation was the best model to describe the process .The pseudothermodynamic parameters,i.e.the net reaction energy,the activation entropy, activation enthalpy and activation free energy of the diffusion,were dervied from the absolute reaction-rate theory.The results showed that these parameters decreased in the order of loessal soil>black lu soil> lou soil> yellow cinnamon soil,which indicated that the force an the heat-energy barrier to be overcome for diffusion decreased ,the diffusion rate increased and the disorder of the soil-solution-ion system due to diffusion decreased successively with the texture becoming heavier in the four soils.

  19. Investigation of the pitting of aluminum induced by chloride ions by holographic microphotography

    Directory of Open Access Journals (Sweden)

    LIANG LI

    2008-05-01

    Full Text Available Holographic microphotography was used to investigate the dynamic processes of pitting during anodic dissolution of aluminum in a solution containing chloride ions. The induction and the follow-up propagation processes of the pitting were observed in real-time. A simple model of the propagating process of the pitting was deduced from the result of the holograms of the Al/electrolyte interface. The results prove that holographic microphotography is a useful tool to study the dynamic processes of pitting.

  20. Copper electrodeposition from cuprous chloride solutions containing lead, zinc or iron ions

    Institute of Scientific and Technical Information of China (English)

    M. Tchoumou; M. Roynette Ehics

    2005-01-01

    Cuprous chloride hydrochloric acid solutions were electrolysed in a two compartments cell without agitation for copper extraction. It is found that the current density affects the colour and the size of copper deposits. During electrodeposition of copper from cuprous solution in the presence of various concentrations of lead, zinc or iron ions at different current densities, it is observed that lead is codeposited with copper by increasing current density.In all experiments, the current efficiency for the copper deposition reaction fluctuates between 88.50% and 95.50%.

  1. Corrosion of Carbon Steel and Corrosion-Resistant Rebars in Concrete Structures Under Chloride Ion Attack

    Science.gov (United States)

    Mohamed, Nedal; Boulfiza, Mohamed; Evitts, Richard

    2013-03-01

    Corrosion of reinforced concrete is the most challenging durability problem that threatens reinforced concrete structures, especially structures that are subject to severe environmental conditions (i.e., highway bridges, marine structures, etc.). Corrosion of reinforcing steel leads to cracking and spalling of the concrete cover and billions of dollars are spent every year on repairing such damaged structures. New types of reinforcements have been developed to avoid these high-cost repairs. Thus, it is important to study the corrosion behavior of these new types of reinforcements and compare them to the traditional carbon steel reinforcements. This study aimed at characterizing the corrosion behavior of three competing reinforcing steels; conventional carbon steel, micro-composite steel (MMFX-2) and 316LN stainless steel, through experiments in carbonated and non-carbonated concrete exposed to chloride-laden environments. Synthetic pore water solutions have been used to simulate both cases of sound and carbonated concrete under chloride ions attack. A three-electrode corrosion cell is used for determining the corrosion characteristics and rates. Multiple electrochemical techniques were applied using a Gamry PC4™ potentiostat manufactured by Gamry Instruments (Warminster, PA). DC corrosion measurements were applied on samples subjected to fixed chloride concentration in the solution.

  2. Functional modifications of acid-sensing ion channels by ligand-gated chloride channels.

    Directory of Open Access Journals (Sweden)

    Xuanmao Chen

    Full Text Available Together, acid-sensing ion channels (ASICs and epithelial sodium channels (ENaC constitute the majority of voltage-independent sodium channels in mammals. ENaC is regulated by a chloride channel, the cystic fibrosis transmembrane conductance regulator (CFTR. Here we show that ASICs were reversibly inhibited by activation of GABA(A receptors in murine hippocampal neurons. This inhibition of ASICs required opening of the chloride channels but occurred with both outward and inward GABA(A receptor-mediated currents. Moreover, activation of the GABA(A receptors modified the pharmacological features and kinetic properties of the ASIC currents, including the time course of activation, desensitization and deactivation. Modification of ASICs by open GABA(A receptors was also observed in both nucleated patches and outside-out patches excised from hippocampal neurons. Interestingly, ASICs and GABA(A receptors interacted to regulate synaptic plasticity in CA1 hippocampal slices. The activation of glycine receptors, which are similar to GABA(A receptors, also modified ASICs in spinal neurons. We conclude that GABA(A receptors and glycine receptors modify ASICs in neurons through mechanisms that require the opening of chloride channels.

  3. One and two dimensional chloride ion diffusion of fly ash concrete under flexural stress

    Institute of Scientific and Technical Information of China (English)

    Yun-sheng ZHANG; Wei SUN; Zhi-yong LIU; Shu-dong CHEN

    2011-01-01

    A preloading frame is firstly designed to accurately apply external flexural stress to concrete specimens.Then a method is developed to measure one and two dimensional (1D and 2D) chloride ion concentrations at different distances from the surface of concrete under flexural stress.Using this method and the preloading frame,1D and 2D stress-diffusion is systematically investigated for fly ash concretes made with different fly ash contents (0%,10%,20%,40%,and 60%),and water to binder ratios (0.3,0.35,and 0.4).The stress accelerating effect on 1D and 2D chloride ion diffusion is also quantitatively analyzed through a comparison between stress-diffusion and nonstress-diffusion.A diffusion accelerating effect caused by external flexural stress can clearly be observed through the comparison.In order to quantify the stress accelerating effect,a stress accelerating factor is proposed in this paper.The relationship between stress accelerating factor and external stress-to-ultimate stress ratio is given as an exponential function.Finally,the process of the initiation,prorogation,and distribution of microcracks on the tensile face of specimen is observed in-situ by using a small-sized loading frame and scanning electron microscope (SEM).The above research provides an insight into chloride attack on the edge reinforcing bars of concrete structures under flexural stress,such as large-span beam and board in the field of civil engineering.

  4. Chloride ion addition for controlling shapes and properties of silver nanorods capped by polyvinyl alcohol synthesized by polyol method

    Science.gov (United States)

    Junaidi, Triyana, Kuwat; Harsojo, Suharyadi, Edi

    2016-04-01

    We report our investigation on the effect of chloride ions oncontrolling the shapes and properties of silver nanorods(AgNRs) synthesized using a polyol method. In this study, we used polyvinyl alcohol (PVA) as a capping agent and sodium chloride (NaCl) as asalt precursor and performed at the oilbath temperature of 140 °C. The chloride ions originating from the NaCl serve to control the growth of the silver nanorods. Furthermore, the synthesized silver nanorodswere characterized using UV-VIS, XRD, SEM and TEM. The results showed that besides being able to control the growth of AgCl atoms, the chloride ions were also able to control the growth of multi-twinned-particles into the single crystalline silver nanorods by micrometer-length. At an appropriate concentration of NaCl, the diameter of silver nanorodsdecreased significantly compared to that of without chloride ion addition. This technique may be useful since a particular diameter of silver nanorods affects a particular application in the future.

  5. Chloride ion addition for controlling shapes and properties of silver nanorods capped by polyvinyl alcohol synthesized using polyol method

    Science.gov (United States)

    Junaidi, Yunus, Muhammad; Triyana, Kuwat; Harsojo, Suharyadi, Edi

    2016-04-01

    We report our investigation on the effect of chloride ions on controlling the shapes and properties of silver nanorods (AgNRs) synthesized using a polyol method. In this study, we used polyvinyl alcohol (PVA) as a capping agent and sodium chloride (NaCl) as a salt precursor and performed at the oil bath temperature of 140°C. The chloride ions originating from the NaCl serve to control the growth of the silver nanorods. Furthermore, the synthesized silver nanorods were characterized using SEM and XRD. The results showed that besides being able to control the growth of AgCl atoms, the chloride ions were also able to control the growth of multi-twinned-particles into the single crystalline of silver nanorods by micrometer-length. At an appropriate concentration of NaCl, the diameter of silver nanorods decreased significantly compared to that of without chloride ion addition. This technique may be useful since a particular diameter of silver nanorods affects a particular application in the future.

  6. Corrosion of alloy 22 in phosphate ions effect and chloride containing solutions

    International Nuclear Information System (INIS)

    Alloy 22 belongs to Ni-Cr-Mo family. This alloy resists the most aggressive environments for industrial applications, in oxidizing as well as reducing conditions, because exhibits an excellent uniform and localized corrosion resistance in aqueous solution. Because of its outstanding corrosion resistant, this alloy is one of the candidate to be considered for the outer shell of the canister that would contain high level radioactive nuclear wastes in a geological repository. The aim of this work is to study ion phosphate influence over Alloy 22 corrosion behavior under aggressive conditions, such as high temperature and high ion chloride concentration, where this material might be susceptible to crevice corrosion. Two different types of samples were used: cylinder specimens for uniform corrosion behavior studies and Prismatic Crevice Assembly (PCA) specimens for localized corrosion studies. Electrochemical tests were performed in deaerated aqueous solution of 1 M NaCl and 1 M NaCl with different phosphate additions at 90 C degrees and pH near neutral. The anodic film and corrosion products obtained were studied by SEM/EDS. Cyclic Potentiodynamic Polarization (CPP) curves obtained for uniform corrosion studies, showed an increase of the passivity range in phosphate containing solutions. The passive current value was 1 μA/cm2 approximately in all the tests. PCA electrochemical tests, that combined a CPP with a potentiostatic polarization step for 2 hours in between the forward and reverse scan, showed crevice corrosion development in some cases. The repassivation potential value, determined by the intersection of the forward and the reverse scan, increased with phosphate addition. A complete crevice corrosion inhibition effect was found for phosphate concentration higher than 0.3 M. These results indicate that the passivity potential range depend on phosphate presence and might be related with the incorporation of the anion in the passive film. Results of the tests

  7. Removal of nitrate ions from water by activated carbons (ACs)—Influence of surface chemistry of ACs and coexisting chloride and sulfate ions

    Science.gov (United States)

    Ota, Kazunari; Amano, Yoshimasa; Aikawa, Masami; Machida, Motoi

    2013-07-01

    Adsorptive removal of nitrate ions in aqueous solution using activated carbons (ACs) was examined. After ash was removed from Filtrasorb 400 AC, oxidation and outgassing and several heat treatments were carried out to modify the textural and surface properties of ACs. AC oxidized with 8 M nitric acid followed by outgassing at 900 °C (Ox-9OG) exhibited the greatest Langmuir adsorption capacity and affinity for nitrate removal among the total 7 ACs examined. Influence of coexisting chloride and sulfate ions was investigated as well to inspect the nitrate adsorption sites. The highest amount of sites which adsorbed nitrate ions exclusively could be observed for Ox-9OG adsorbent even though as great as 250 times greater number of chloride or sulfate ions over nitrate ions were present in the same aqueous system. Some basic oxygen species on carbon were estimated to work as selective adsorption sites for nitrate ions.

  8. Determination of the stability constants of lanthanum, praseodymium, europium, erbium and lutetium complexes with chloride ions

    International Nuclear Information System (INIS)

    The stability constants of La3+, Pr3+, Eu3+, Er3+ and Lu3+ chloride complexes were determined in perchloric acid media using a liquid-liquid extraction method. The dinonyl napthalene sulfonic acid in n-heptane was used as extractant. The lanthanide (Ln) concentrations were measured by a radiochemical (Eu and Lu) and a spectrophotometric (La, Pr, and Er) methods. In the last method, xylenol orange was used for the determinations at ph 6. The stability constants of lanthanum, praseodymium, erbium and lutetium chloride complexes were determined in 2, 3 and 4 M ionic strength and europium in 1, 2 and 3 M, at 303 K. The fitting of experimental data to the equations for the calculation of the stability constants, was carry out considering both one chemical species (LnCl2+) or two chemical species (LnCl2+ and LnCl2+). The Specific Ion Interaction Theory was applied to the values of log βILn,Cl and the first stability constants at zero ionic strength were calculated by extrapolation. The same theory could not be applied to the log βILn,2Cl, due to its low abundance and the values determined for the stability constants were similar. The distribution diagrams of the chemical species were obtained using the program MEDUSA and considering log βILn,CI, log βILn,2CI values obtained in this work and the hydrolysis constants taken from the literature. The lanthanide chloride complexes are present in solution at specific conditions of ionic strength, concentration and in the absence of hydrolysis. The log βILn,Cl data were related to the charge density and the corresponding equations were obtained. These equations could be used to determine the stability constants along the lanthanide series. (Author)

  9. Involvements of chloride ion in decolorization of Acid Orange 7 by activated peroxydisulfate or peroxymonosulfate oxidation

    Institute of Scientific and Technical Information of China (English)

    Ping Wang; Shiying Yang; Liang Shan; Rui Niu; Xueting Shao

    2011-01-01

    The effects of chloride anion (C1-) (up to 1.0 mol/L) on the decolorization of a model compound,azo dye Acid Orange 7 (AO7),by sulfate radical (SO4-*) based-peroxydisulfate (PS) or peroxymonosulfate (PMS) oxidation under various activated conditions (UV254 nm/PS,Thermal (70℃/PS,UV254 nm/PMS,Co2+/PMS) were investigated.Methanol and NH4+ were used as quenching reagents to determine the contributions of active chlorine species (dichloride radical (Cl2-*) and hypochlorous acid (HClO)).The results indicated that the effects of Cl- on the reaction mechanism were different under various activated conditions.For UV/PS and Thermal/PS,the inhibition tendency became more clear as the Cl-concentration increased,probably due to the reaction between Cl- and SO4-* and the generation of Cl2-* or HClO.For UV/PMS,Cl- did not exhibit inhibition when the concentration was below 0.1 mol/L.As Cl-concentration reached to 1.0 mol/L,the decolorization rate of AO7 was,however,accelerated,possibly because PMS directly reacts with C1- to form HC1O.For Co2+/PMS,Cl- exhibited a significant inhibiting effect even at low concentration (≤ 0.01 mol/L).When Cl- concentration exceeded 0.1 mol/L,the activation of PMS by Co2+ was almost completely inhibited.Under this condition,HClO maybe played a major role in decolorization of AO7.The results implicated that chloride ion is an important factor in SO4-*-based degradation of organic contamination in chloride-containing water.

  10. Secretion by the nasal salt glands of two insectivorous lizard species is initiated by an ecologically relevant dietary ion, chloride.

    Science.gov (United States)

    Hazard, Lisa C; Lechuga, Claudia; Zilinskis, Stephanie

    2010-08-01

    Salt glands are used by some vertebrates to excrete hyperosmotic NaCl or KCl solutions in response to dietary salt loads. Control of secretion varies across taxa; some secrete in response to osmotic challenges while others secrete in response to specific dietary ions. We hypothesized that differences in control could be related to different diet-related selective pressures on herbivorous, marine, and insectivorous species. We studied control of secretion and flexibility of cation (sodium or potassium) and anion (chloride or bicarbonate) secretion in two insectivorous lizard species, Schneider's skinks (Eumeces schneideri, Scincidae) and green anoles (Anolis carolinensis, Polychrotidae). Lizards were injected daily for four days with combinations of cations (potassium, sodium, and histidine control) and anions (chloride and acetate control), isoosmotic saline, or sham injection. Secretions were collected daily and analyzed for sodium, potassium, and chloride. Both species secreted only in response to chloride; sodium appeared to have a slight inhibitory effect. Regardless of cation load, skinks secreted a combination of potassium and sodium, while anoles secreted solely potassium. In both species, total cation secretion was matched closely by chloride; very little bicarbonate was secreted. As predicted, secretion in insectivorous lizards was initiated by the dietary ion ecologically most important for these species, chloride, which otherwise cannot be excreted without significant water loss (unlike the cations, which may be excreted as insoluble urate salts). This gives further support to the hypothesis that ecological factors drive the evolution of control mechanisms in lizard salt glands. PMID:20623801

  11. Determination of the stability of the uranyl ion sipped in {tau}-hydrogen phosphate of zirconium in sodic form; Determinacion de la estabilidad del ion uranilo sorbido en {tau}-hidrogenofosfato de zirconio en forma sodica

    Energy Technology Data Exchange (ETDEWEB)

    Ordonez R, E.; Fernandez V, S.M. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Drot, R.; Simoni, E. [Universite de Paris-Sud-XI, Institut de Physique Nucleaire d' Orsay, Groupe de radiochimie, Bat. 100, 91406 Orsay (France)]. e-mail: edo@nuclear.inin.mx

    2005-07-01

    The stability of the uranyl sipped in the zirconium {tau}-hydrogen phosphate in sodic form ({tau}-NaZrP), was carried out characterizing the complexes formed by Laser spectroscopy in the visible region and by X-ray photoelectron spectroscopy. The material was prepared by a new synthesis technique working in nitrogen atmosphere and to low temperatures. The sorption of the uranyl ion was made in acid media with concentrations of 10{sup -4} and 10{sup -5} of uranyl nitrate and with ion forces of 0.1 and 0.5 M of NaClO{sub 4}. The spectra of induced fluorescence with laser (TRLFS) show that the uranyl is fixed in very acid media in three well differentiated species, to pH less acid, the specie of long half life disappears and are only those of short half life. The results of the binding energy obtained by XPS indicate that the binding energy of the uranyl confer it a stable character to the complex formed in the {tau}-NaZP, that makes to this material appropriate to retain to the uranyl in solution to high ion forces and in acid media. (Author)

  12. A Systematic Study of Chloride Ion Solvation in Water using van der Waals Inclusive Hybrid Density Functional Theory

    OpenAIRE

    Bankura, Arindam; Santra, Biswajit; DiStasio Jr., Robert A.; Swartz, Charles W.; Klein, Michael L.; Wu, Xifan

    2015-01-01

    In this work, the solvation and electronic structure of the aqueous chloride ion solution was investigated using Density Functional Theory (DFT) based \\textit{ab initio} molecular dynamics (AIMD). From an analysis of radial distribution functions, coordination numbers, and solvation structures, we found that exact exchange ($E_{\\rm xx}$) and non-local van der Waals (vdW) interactions effectively \\textit{weaken} the interactions between the Cl$^-$ ion and the first solvation shell. With a Cl-O...

  13. An Accelerated Test Method of Simultaneous Carbonation and Chloride Ion Ingress: Durability of Silica Fume Concrete in Severe Environments

    Directory of Open Access Journals (Sweden)

    S. A. Ghahari

    2016-01-01

    Full Text Available The effects of simultaneous carbonation and chloride ion attack on mechanical characteristics and durability of concrete containing silica fume have been investigated through an accelerated test method. Specimens containing different amounts of silica fume were maintained in an apparatus in which carbon dioxide pressure and concentration and relative humidity were kept constant, and wetting and drying cycles in saline water were applied. Surface resistivity, sorptivity, CO2 consumption, and carbonation and chloride ion ingress depths measurements were taken. Phase change due to carbonation and chloride ion attack was monitored by XRD analysis, and microstructures and interfacial transition zones were studied by implementing SEM as well as mercury intrusion porosimetry. It was expected to have a synergistic effect in the tidal zone where simultaneous carbonation and chloride ion attack happen. However, the observed reduced surface resistivity, compared to specimens maintained in CO2 gas, could be due to the moisture that is available near the surface, hindering CO2 from penetrating into the pores of the specimens. Moreover, the porosity analysis of the specimens showed that the sample containing silica fume cured in the tidal zone had 50.1% less total porosity than the plain cement paste cured in the same condition.

  14. Synergistic effect between cationic gemini surfactant and chloride ion for the corrosion inhibition of steel in sulphuric acid

    Energy Technology Data Exchange (ETDEWEB)

    Qiu Lingguang [School of Chemistry and Chemical Engineering, Anhui University, Hefei 230039 (China)], E-mail: lgqiu@ahu.edu.cn; Wu Yun; Wang Yimin; Jiang Xia [School of Chemistry and Chemical Engineering, Anhui University, Hefei 230039 (China)

    2008-02-15

    Corrosion inhibition of cold rolled steel in 0.5 mol L{sup -1} sulphuric acid by a quaternary ammonium gemini surfactant, l,3-propane-bis(dimethyl dodecylammonium bromide) (designated as 12-3-12), in the absence and presence of chloride ions was investigated at different temperatures. The results revealed significant synergistic effect between gemini 12-3-12 and chloride ions for the corrosion protection of cold rolled steel in sulphuric acid, and that the novel composite inhibitor system containing cationic gemini surfactant and chloride ions was efficient and low-cost for steel corrosion inhibition in sulphuric acid medium, even when concentration of 12-3-12 was as low as 1 x 10{sup -6} mol L{sup -1}. By fitting the obtained experimental data with Langmuir adsorption model and Arrhenius equation, some thermodynamic and kinetic parameters such as adsorption free energy, the apparent activation energy, and the pre-exponential factor were estimated. The adsorption mechanism of the gemini surfactant onto steel surface in acid medium in the absence and presence of chloride ions was also discussed, respectively.

  15. Chloride ion-catalyzed generation of difluorocarbene for efficient preparation of gem-difluorinated cyclopropenes and cyclopropanes

    KAUST Repository

    Wang, Fei

    2011-01-01

    A chloride ion-catalyzed generation of difluorocarbene from a relatively non-toxic and inexpensive precursor, Me3SiCF2Cl (1), under mild and neutral conditions leads to an efficient preparation of gem-difluorocyclopropenes and difluorocyclopropanes through [2 + 1] cycloaddition reactions with alkynes and alkenes, respectively. © 2011 The Royal Society of Chemistry.

  16. Sorption of uranium(VI) ions from hydrochloric acid and ammonium chloride solutions by anion exchangers

    International Nuclear Information System (INIS)

    The sorption of macroscopic quantities of uranium from solutions of UO2Cl2 containing HCl and NH4Cl in concentrations from 0.0 to 6.0 M by the AV-17 x 8, AV-16G, EDE-10P, AN-31, AN-2F, AN22, and AN-251 anion exchangers has been investigated under static conditions. The sorption isotherms are described by an equation similar to Freundlich's equation: K/sub d/ = K tilde x C/sub eq/sup 1/z/ or log K/sub d/ = log K tilde + 1/z x log C/sub eq/. Equations describing the dependence of the sorbability (or K/sub d/) on the equilibrium concentration of uranium in the solution have been obtained with the aid of the least-squares method. Conclusions regarding the chemistry of the exchange of uranium ions on anion exchangers in chloride solutions have been drawn on the basis of the UV spectra of the original solutions and the IR spectra of the ion exchangers obtained in this work, as well as the established general laws governing sorption

  17. Sorption of uranium(VI) ions from hydrochloric acid and ammonium chloride solutions by anion exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Pakholkov, V.S.; Denisova, L.A.; Rychkov, V.N.; Kurnosenko, N.A.

    1988-01-01

    The sorption of macroscopic quantities of uranium from solutions of UO/sub 2/Cl/sub 2/ containing HCl and NH/sub 4/Cl in concentrations from 0.0 to 6.0 M by the AV-17 x 8, AV-16G, EDE-10P, AN-31, AN-2F, AN22, and AN-251 anion exchangers has been investigated under static conditions. The sorption isotherms are described by an equation similar to Freundlich's equation: K/sub d/ = K tilde x C/sub eq/sup 1/z/ or log K/sub d/ = log K tilde + 1/z x log C/sub eq/. Equations describing the dependence of the sorbability (or K/sub d/) on the equilibrium concentration of uranium in the solution have been obtained with the aid of the least-squares method. Conclusions regarding the chemistry of the exchange of uranium ions on anion exchangers in chloride solutions have been drawn on the basis of the UV spectra of the original solutions and the IR spectra of the ion exchangers obtained in this work, as well as the established general laws governing sorption.

  18. Effects of Chloride Ion on the Texture of Copper and Cu-ZrB2 Coatings Electrodeposited from Copper Nitrate Solution in Different Plating Modes

    Institute of Scientific and Technical Information of China (English)

    Dongming GUO; Min ZHANG; Zhuji JIN; Renke KANG

    2006-01-01

    For the first time, the texture of copper and Cu-ZrB2 coatings produced from copper nitrate solution was studied. Chloride ion shows different effects on the deposit texture under direct current(DC)and pulse ion concentration exceeds 20 mg/I. The addition of ZrB2 particles enhances the cathodic polarization of copper deposition, which improves the growth of(111)plane. However, this improvement can be eliminated by further addition of chloride ion.

  19. Separation of chloride ion from leach liquor and its effect on Uranium analysis followed by solvent extraction

    International Nuclear Information System (INIS)

    In this research work the chloride and sulfate ions have been decreased in the leach liquors using Hydrofluoric acid 40% and commercial lead nitrate prepared by sea water in sulfuric acid media. As the result of chloride ion deduction in leach liquor the relative competition of uranium with other elements to transfer to normal TB P structure as solvent extractant of uranium will be also reduced. It is investigated that in nitrated media of leach solution more uranium will transfer to TB P phase. Then reextraction and analysis were done by colorimetric method of developing uranyl ferrocyanide complex in 540 nm as the fixed wavelength. In this study the interfering effect of fluoride ion is also considered and evaluated by the above mentioned complex. Comparing the results of uranium analysis obtained by I C P technique show that the effect of fluoride as an interfering ion is more serious in single stage than multistage of chloride precipitation process. Promising signs of analytical results have led us to be familiar with the high purity yellow cake production know-how as well. This separation procedure is well organized and well suited to apply on the uranium resources called salted arches shaped. Besides, in this study the successful quantitative separation of better than 99% of molybdenum from uranium is also considered

  20. Highly improved voltage efficiency of seawater battery by use of chloride ion capturing electrode

    Science.gov (United States)

    Kim, Kyoungho; Hwang, Soo Min; Park, Jeong-Sun; Han, Jinhyup; Kim, Junsoo; Kim, Youngsik

    2016-05-01

    Cost-effective and eco-friendly battery system with high energy density is highly desirable. Herein, we report a seawater battery with a high voltage efficiency, in which a chloride ion-capturing electrode (CICE) consisting of Ag foil is utilized as the cathode. The use of Ag as the cathode leads to a sharp decrease in the voltage gaps between charge and discharge curves, based on reversible redox reaction of Ag/AgCl (at ∼2.9 V vs. Na+/Na) in a seawater catholyte during cycling. The Ag/AgCl reaction proves to be highly reversible during battery cycling. The battery employing the Ag electrode shows excellent cycling performance with a high Coulombic efficiency (98.6-98.7%) and a highly improved voltage efficiency (90.3% compared to 73% for carbonaceous cathode) during 20 cycles (total 500 h). These findings demonstrate that seawater batteries using a CICE could be used as next-generation batteries for large-scale stationary energy storage plants.

  1. Electrochemical corrosion characteristics of aluminium alloy 6061 T6 in demineralized water containing 0.1 % chloride ion

    International Nuclear Information System (INIS)

    Direct current electrochemical method is one of the techniques has been used to study the corrosion behaviour of metal/ alloy in its environment. This paper attempts to investigate the corrosion behaviour of Al 6061 T6 immersed in Reactor TRIGA Mark II pool water containing about 0.1 % NaCl content. The result shown that the corrosion rate value of the aluminium 6061 T6 increased with the presence of 0.1 % Ion Chloride content in the demineralized water reactor pool as compared to normal demineralized water. This is due to aggressiveness of chloride ion attack to metal surface. Beside corrosion rate analysis, the further tests such as corrosion behaviour diagram, cyclic polarization have been carried and the results have been reported. (Author)

  2. Electrochemical corrosion characteristics of aluminium alloy 6061 T6 in demineralized water containing 0.1 % chloride ion

    International Nuclear Information System (INIS)

    Direct current electrochemical method is one of the techniques has been used to study the corrosion behaviour of metal/alloy in its environment. This paper attempts to investigate the corrosion behaviour of Al 6061 T6 immersed in Reactor TRIGA Mark II pool water containing about 0.1% NaCl content. The result shown that the corrosion rate value of the aluminium 6061 T6 increased with the presence of 0.1 % Ion Chloride content in the demineralized water reactor pool as compared to normal demineralized water. This is due to aggressiveness of chloride ion attack to metal surface. Beside corrosion rate analysis, the further tests such as corrosion behaviour diagram, cyclic polarization have been carried and the results have been reported. (author)

  3. An Accelerated Test Method of Simultaneous Carbonation and Chloride Ion Ingress: Durability of Silica Fume Concrete in Severe Environments

    OpenAIRE

    Ghahari, S. A.; Ramezanianpour, A. M.; Ramezanianpour, A. A.; Esmaeili, M

    2016-01-01

    The effects of simultaneous carbonation and chloride ion attack on mechanical characteristics and durability of concrete containing silica fume have been investigated through an accelerated test method. Specimens containing different amounts of silica fume were maintained in an apparatus in which carbon dioxide pressure and concentration and relative humidity were kept constant, and wetting and drying cycles in saline water were applied. Surface resistivity, sorptivity, CO2 consumption, and c...

  4. Compressive Strength, Pore Size Distribution and Chloride-ion Penetration of Recycled Aggregate Concrete Incorporating Class-F Fly Ash

    Institute of Scientific and Technical Information of China (English)

    KOU Shicong; C S Poon

    2006-01-01

    The effects of fly ash on the compressive strength, pore size distribution ard chloride-ion penetration of recycled aggregate concrete were investigated. Two series of concrete mixtures were prepared. The concrete mixtures in series I had a water-to-binder ratio and a cement content of 0.55 and 410 kg/m3 , respectively. The concrete mixtures in series Ⅱ had a water-to-binder ratio and a cement content of 0.45 and 400 kg/m3 respectively. Recycled aggregate was used as 20% , 50% , and 100% replacements of natural coarse aggregate in the concrete mixtures in both series. In addition, fly ash was used as 0% , 25% and 35% by weight replacements of cement. The results show that the compressive strengths of the concrete decreased as the recycled aggregate and the fly ash contents increased. The total porosity and average porosity diameter of the concrete increased as the recycled aggregate content increased. Furthermore, an increase in the recycled aggregate content decreased the resistance to chloride ion penetration. Nevertheless, the replacement of cement by 25% fly ash improved the resistance to chloride ion penetration and pore diameters and reduced the total porosity of the recycled aggregate concrete.

  5. Effects of anodic potential and chloride ion on overall reactivity in electrochemical reactors designed for solar-powered wastewater treatment.

    Science.gov (United States)

    Cho, Kangwoo; Qu, Yan; Kwon, Daejung; Zhang, Hao; Cid, Clément A; Aryanfar, Asghar; Hoffmann, Michael R

    2014-02-18

    We have investigated electrochemical treatment of real domestic wastewater coupled with simultaneous production of molecular H2 as useful byproduct. The electrolysis cells employ multilayer semiconductor anodes with electroactive bismuth-doped TiO2 functionalities and stainless steel cathodes. DC-powered laboratory-scale electrolysis experiments were performed under static anodic potentials (+2.2 or +3.0 V NHE) using domestic wastewater samples, with added chloride ion in variable concentrations. Greater than 95% reductions in chemical oxygen demand (COD) and ammonium ion were achieved within 6 h. In addition, we experimentally determined a decreasing overall reactivity of reactive chlorine species toward COD with an increasing chloride ion concentration under chlorine radicals (Cl·, Cl2(-)·) generation at +3.0 V NHE. The current efficiency for COD removal was 12% with the lowest specific energy consumption of 96 kWh kgCOD(-1) at the cell voltage of near 4 V in 50 mM chloride. The current efficiency and energy efficiency for H2 generation were calculated to range from 34 to 84% and 14 to 26%, respectively. The hydrogen comprised 35 to 60% by volume of evolved gases. The efficacy of our electrolysis cell was further demonstrated by a 20 L prototype reactor totally powered by a photovoltaic (PV) panel, which was shown to eliminate COD and total coliform bacteria in less than 4 h of treatment. PMID:24417418

  6. Effect of cationic composition of the medium on ruthenium(4) complexing with chloride- and bromide-ions

    International Nuclear Information System (INIS)

    Spectrophotometric method was used to study the process of substitution of chloride- and bromide-ions for water molecules in ruthenium(4) aqua complex in different media and in wide range of ligand concentrations (0.02-11 mol/l). Substitution of cation of background electrolyte in Na-Li-H series results to the shift of equilibrium of the reaction of Ru(4) chloro-and bromocomplex formation to the side of formation of complex forms, characterized by higher coordination saturation with halide-ions

  7. The Effect of Early Frost Damage on the Penetration Resistance of Chloride Ion of NPP Concrete

    Energy Technology Data Exchange (ETDEWEB)

    Koh, Kyung Teak; Park, Chun Jin; Kim, Si Hwan; Ryu, Gum Sung [Korea Institute of Construction Technology, Goyang (Korea, Republic of)

    2012-05-15

    The specification for the nuclear power plant (NPP) structure construction specifies the conformity of the regulation ACI-306R in constructing the cold-weather concrete. According to the regulation with regard to the curing condition for cold weather concrete, the insulation curing of cold weather concrete should be appropriately performed under the environment of 5 .deg. C or more until the strength of 500 psi is developed. In addition, according to the regulations regarding the cold weather concrete in the domestic concrete specifications, the insulation curing should be performed until the strength development of 715 psi considering the safety factor indicated to the ACI regulation under the temperature of 5 .deg. C or more. According to the above-mentioned regulations, the NPP structure is required to develop the minimum strength of 715 psi or more and to maintain the important quality including strength development, early anti-freezing and duality under the cold weather condition. However, even though the early strength of 715 psi or more is secured under cold weather condition, if the structure is exposed to the continuous cold weather condition after the protection equipment including curing coat are removed, the structure's durability can go down compared to the concrete cured under the standard curing temperature condition in spring and fall, but the studies on this status still remain poor. Accordingly, this study tried to verify the adequacy of the insulation curing management standard, which is currently presented, in time of constructing the cold weather concrete, through reviewing the penetration resistance of chloride ion with considering the local characteristics of domestic NPP located at coastal areas after curing until the point of 715 psi, then exposing it to a certain cycle of freeze-thaw environment under the continuous cold weather condition

  8. The Effect of Early Frost Damage on the Penetration Resistance of Chloride Ion of NPP Concrete

    International Nuclear Information System (INIS)

    The specification for the nuclear power plant (NPP) structure construction specifies the conformity of the regulation ACI-306R in constructing the cold-weather concrete. According to the regulation with regard to the curing condition for cold weather concrete, the insulation curing of cold weather concrete should be appropriately performed under the environment of 5 .deg. C or more until the strength of 500 psi is developed. In addition, according to the regulations regarding the cold weather concrete in the domestic concrete specifications, the insulation curing should be performed until the strength development of 715 psi considering the safety factor indicated to the ACI regulation under the temperature of 5 .deg. C or more. According to the above-mentioned regulations, the NPP structure is required to develop the minimum strength of 715 psi or more and to maintain the important quality including strength development, early anti-freezing and duality under the cold weather condition. However, even though the early strength of 715 psi or more is secured under cold weather condition, if the structure is exposed to the continuous cold weather condition after the protection equipment including curing coat are removed, the structure's durability can go down compared to the concrete cured under the standard curing temperature condition in spring and fall, but the studies on this status still remain poor. Accordingly, this study tried to verify the adequacy of the insulation curing management standard, which is currently presented, in time of constructing the cold weather concrete, through reviewing the penetration resistance of chloride ion with considering the local characteristics of domestic NPP located at coastal areas after curing until the point of 715 psi, then exposing it to a certain cycle of freeze-thaw environment under the continuous cold weather condition

  9. Study by X-ray photoelectron spectroscopy (XPS) and radiochemistry (Cl36) of the interaction of chloride ions with a passive film formed on nickel

    International Nuclear Information System (INIS)

    This research thesis reports the study of the influence of chlorides on nickel passivation by using a radiochemical method based on the use of the Cl36 isotope and the X-ray photoelectron spectroscopy (XPS). The first one allows the in-situ determination of the adsorption of chlorides on the surface, or their inclusion in surface films during the electrochemical treatment. The XPS analysis allows the characterization of modifications induced by chlorides in passive films. The obtained results allow a better understanding in the interpretation of the mechanisms of corrosion induced by chloride ions

  10. Comparative measurements of potassium and chloride with ion-sensitive microelectrodes and x-ray microanalysis in cultured skeletal muscle fibers

    International Nuclear Information System (INIS)

    Data of the intracellular electrolyte concentration of potassium and chloride in cultured muscle cells measured by x-ray analysis were compared by using the different activity coefficients with intracellular potassium and chloride activities measured with double-barrelled microelectrodes. By using an activity coefficient of 0.6, 95% of the potassium microelectrode measurements are in accordance with the x-ray analysis values, in spite of a scattering of the values. Membrane potential and intracellular potassium values are linearly related. x-ray analysis and ion-sensitive microelectrodes measured the cytoplasmic chloride in the same range. Taking into account known activity coefficients, an error of 25% must be assumed with the intracellular chloride measurements. However, x-ray analysis and ion-sensitive microelectrode investigations are reliable tools to study intracellular potassium and chloride changes, which play an important role in membrane characteristics

  11. Effect of sulfate reducing bacteria on corrosion of stainless steel 1Cr18Ni9Ti in soils containing chloride ions

    International Nuclear Information System (INIS)

    Research highlights: → The effect of SRB on corrosion of the stainless steel was investigated. → The effect of chloride ion on corrosion of the stainless steel was investigated. → Pitting susceptibility of the steel was enhanced by SRB and chloride ion. → Many pitting holes were clearly observed on the surface of the steel. - Abstract: The effect of sulfate reducing bacteria (SRB) on corrosion of stainless steel 1Cr18Ni9Ti in soils containing chloride ions was studied by bacterial analysis, electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDXA). The results showed that the corrosion rate of the steel in soils containing chloride with SRB was larger than that without SRB under the lower chloride ion concentration of 1 wt%. The observations on pitting corrosion of the steel in soils containing the same amount of SRB, however with different chloride concentration revealed that the pitting depth increased with increasing chloride concentration. There existed in the measured EIS only one capacitive loop for the steel in the soil without SRB, and two capacitive loops for that with SRB.

  12. Studies of removal of palladium(II) ions from chloride solutions on weakly and strongly basic anion exchangers.

    Science.gov (United States)

    Hubicki, Z; Wołowicz, A; Leszczyńska, M

    2008-11-30

    Palladium and its compounds find wide application in industry as a catalytic agent in different manufacture processes. Recovery of precious metals from industrial wastes is difficult and time consuming but in spite of these disadvantages it becomes profitable. Palladium(II) ions sorption from various chloride solutions of the composition: 0.1-6.0M HCl-0.00056 M Pd(II), 1.0M ZnCl(2)-0.1M HCl-0.00056 M Pd(II), 1.0M AlCl(3)-0.1M HCl-0.00056 M Pd(II) on the weakly and strongly basic anion exchangers (Varion ATM, Varion ADM and Varion ADAM) was discussed. The sorption research of Pd(II) ions on these resins was carried out by means of static and dynamic methods. The dynamic processes were applied in order to determine the breakthrough curves of Pd(II) ions. Moreover, the working ion-exchange capacities as well as the weight and bed distribution coefficients were determined from the Pd(II) breakthrough curves. The recovery factors of Pd(II) ions (% R) depending on the phase contact time were obtained by means of static methods. The highest ion-exchange capacities for the 0.1-6.0M HCl-0.00056 M Pd(II) systems were obtained for the weakly basic ion-exchange resin Varion ADAM. PMID:18358602

  13. Determination of diallyldimethylammonium chloride in drinking water by reversed-phase ion-pair chromatography-electrospray ionization mass spectrometry.

    Science.gov (United States)

    Jin, Fen; Hu, Jianying; Yang, Min; Jin, Xiaohui; He, Wenjie; Han, Hongda

    2006-01-01

    A method for the direct determination of diallyldimethylammonium chloride (DADMAC) in water samples, using ion-pair liquid chromatography-mass spectrometry system was developed. The chromatographic separation was performed using a C18 column. The type, the concentration of ion-pair reagent and the pH were optimized to give good chromatographic retention and sensitivity for DADMAC. Quantification was achieved in the positive electrospray ionization mode using selected ion monitoring. The cone voltage was also studied to establish the optimal experimental conditions. Finally, the reproducibility of the proposed method was shown by good run-to-run and day-to-day precision values. No sample preparation was required and the detection limit was 0.1 microg/L. The method was used to detect residual DADMAC at drinking water treatment plants in Tianjin, north China. The concentration of DADMAC observed in drinking water ranged from below quantitation limit to 22.0 microg/L. PMID:16243342

  14. Interaction of the chloride intracellular ion channel protein CLIC1 with different sterols in model membranes

    International Nuclear Information System (INIS)

    Background and Aims: Sterols have been reported to modulate conformation and hence the function of several membrane proteins. One such group is the Chloride Intracellular Ion Channel (CLIC) family of proteins. The CLIC protein family consists of six evolutionarily conserved protein members in vertebrates. These proteins are unusual, existing as both monomeric soluble proteins and as membrane bound proteins. We now for the first time demonstrate that the spontaneous membrane insertion of CLIC1 is dependent on the presence of cholesterol in membranes. Our novel findings also extend to the identification of a cholesterol-binding domain within CLIC1 that facilitates the spontaneous membrane insertion of the protein into membranes containing cholesterol. Methods: CLIC1 wild type (WT) and mutant proteins were purified by Ni-NTA followed by size‐exclusion chromatography. Langmuir monolayer film balance experiments were carried out using 1-Palmitoyl-2-oleoylphosphatidylcholine (POPC) alone, or in a 5:1 mole ratio combination with either one of the following sterols: Cholesterol (CHOL), β-Sitosterol (SITO), Ergosterol (ERG), Hydroxyecdysone (HYD) or Cholestane (CHOS). WT CLIC1 or mutant versions of CLIC1 were then injected into the aqueous subphase under the lipid film. Results: In lipid monolayers lacking sterols, CLIC1 did not insert. However significant membrane insertion occurred when CLIC1 was added to membranes containing cholesterol. Substitution of membrane cholesterol with either HYD, SITO or ERG, not only increased CLIC1’s membrane interaction but also increased its rate of insertion. Conversely, CLIC1 showed no insertion into monolayers containing CHOS, which lacked the intact sterol 3β-OH group. CLIC1 mutants G18A and G22A, did not insert in POPC:CHOL monolayers whereas the C24A mutant showed membrane insertion equivalent to WT CLIC1. X-ray and Neutron reflectivity, along with Small Angle X-ray Scattering techniques were subsequently used to probe

  15. The effect of chloride ion on the iron elution from carbon steel in high temperature water

    International Nuclear Information System (INIS)

    In Hamaoka-5 nuclear power plant, the sea water entered into the reactor during the shutdown on May in 2011. The structural materials were exposed to the high temperature water containing chloride ion (Cl-). Carbon steel is less corrosion-resistant than stainless steel and the corrosion might be accelerated. Oxide growth of carbon steel may cause the change of Co-60 deposition behavior during the operation. Then the perceiving the state of oxide film on the surface of carbon steel is important. We conducted the corrosion tests for 24hrs with carbon steel under high temperature water containing Cl- to estimate the state of the surface and iron elution of the actual plant. In the cases of the prefilmed specimens, without Cl-, the amount of iron elution was small at 513 K. On the other hand, under the water condition containing Cl- iron elution from carbon steel occurred. The iron elution rate under the water condition of 423 K was slightly faster than 513 K. The average values of iron elution rate under the condition of 400ppm as Cl- were approximately 0.03 mg/cm2/h. The dependency of Cl- concentration on iron elution rate did not appear at the both of 423 and 513 K. In the case of the specimens without oxide film, the iron elution rate under the water condition of 423 K was much faster than 513 K under the water conditions with and without Cl-. The iron elution rate of the specimens without oxide film was affected by the concentration of Cl- with the exception of the test at 423 K. At the higher Cl- concentration, iron elution was accelerated. Furthermore, we conducted the corrosion tests at 323 K for 500 hours which simulated the water condition after the shutdown of the reactor. It was also confirmed that iron apparently eluted from the specimen in these tests. This result indicated that iron elution possibly occurred in the actual plant. The analyses of the oxide film on the surface of specimens after the several tests were conducted. We also discussed the

  16. Lithium ions in nanomolar concentration modulate glycine-activated chloride current in rat hippocampal neurons.

    Science.gov (United States)

    Solntseva, E I; Bukanova, J V; Kondratenko, R V; Skrebitsky, V G

    2016-03-01

    Lithium salts are successfully used to treat bipolar disorder. At the same time, according to recent data lithium may be considered as a candidate medication for the treatment of neurodegenerative disorders. The mechanisms of therapeutic action of lithium have not been fully elucidated. In particular, in the literature there are no data on the effect of lithium on the glycine receptors. In the present study we investigated the effect of Li(+) on glycine-activated chloride current (IGly) in rat isolated pyramidal hippocampal neurons using patch-clamp technique. The effects of Li(+) were studied with two glycine concentrations: 100 μM (EC50) and 500 μM (nearly saturating). Li(+) was applied to the cell in two ways: first, by 600 ms co-application with glycine through micropipette (short application), and, second, by addition to an extracellular perfusate for 10 min (longer application). Li(+) was used in the range of concentrations of 1 nM-1 mM. Short application of Li(+) caused two effects: (1) an acceleration of desensitization (a decrease in the time of half-decay, or "τ") of IGly induced by both 100 μM and 500 μM glycine, and (2) a reduction of the peak amplitude of the IGly, induced by 100 μM, but not by 500 μM glycine. Both effects were not voltage-dependent. Dose-response curves for both effects were N-shaped with two maximums at 100 nM and 1 mM of Li(+) and a minimum at 1 μM of Li(+). This complex form of dose-response may indicate that the process activated by high concentrations of lithium inhibits the process that is sensitive to low concentrations of lithium. Longer application of Li(+)caused similar effects, but in this case 1 μM lithium was effective and the dose-effect curves were not N-shaped. The inhibitory effect of lithium ions on glycine-activated current suggests that lithium in low concentrations is able to modulate tonic inhibition in the hippocampus. This important property of lithium should be considered when using this drug as a

  17. Ion-solvent interactions in lanthanum(III) chloride and D-glucose-water mixed solvent systems: An ultrasonic study

    Science.gov (United States)

    Dash, J. K.; Kamila, Susmita

    2015-09-01

    Acoustic parameters such as isentropic compressibility, βs, intermolecular free length, Lf, apparent molar volume (ϕv), solvation number, Sn, viscosity B coefficients of Jones-Dole equation etc., have been evaluated from the measured values of ultrasonic velocity, density and viscosity for the solutions of lanthanum(III) chloride in d-glucose (dextrose)-water mixed solvent system of various proportions at 303.15 K temperature and atmospheric pressure. The results are discussed in the light of ion-solvent interactions and the structural effect of the solute on the solvent in the solution.

  18. Influence of chloride ion concentration on immersion corrosion behaviour of plasma sprayed alumina coatings on AZ31B magnesium alloy

    OpenAIRE

    D. Thirumalaikumarasamy; K. Shanmugam; Balasubramanian, V

    2014-01-01

    Corrosion attack of aluminium and magnesium based alloys is a major issue worldwide. The corrosion degradation of an uncoated and atmospheric plasma sprayed alumina (APS) coatings on AZ31B magnesium alloy was investigated using immersion corrosion test in NaCl solutions of different chloride ion concentrations viz., 0.01 M, 0.2 M, 0.6 M and 1 M. The corroded surface was characterized by an optical microscope and X-ray diffraction. The results showed that the corrosion deterioration of uncoate...

  19. Preparation of a chitosan-based anionic exchanger for removal of bromide, chloride, iodide and phosphate ions from aqueous solutions

    Directory of Open Access Journals (Sweden)

    Affonso Celso Gonçalves Júnior

    2014-02-01

    Full Text Available The development of a chitosan anion exchanger, obtained from shrimp shells, and its adsorption capacity for chloride, bromide, iodide and phosphate anions are provided. Dependence of exchange processes with the anions as a function of pH and contact time between exchanger and anions were initially investigated. Results showed that the best adsorption of ions occurred at pH 3.0. Exchange isotherms were then developed by the Langmuir, Freundlich and Dubinin-Radushkevich mathematical models. Results demonstrated that chitosan produced from shrimp shells may be used as feedstock in the manufacture of anion exchange microspheres.

  20. Effect of Fly Ash on Frost-Resistance and Chloride Ions Diffusion Properties of Marine Concrete

    Institute of Scientific and Technical Information of China (English)

    YANG Wen-wu; QIAN Jue-shi; ZHANG Yi-ying

    2009-01-01

    It is necessary to pay more attention to the durability of concrete undergoing freeze-thaw cycles and seawater attack simultaneously.Investigated are the effects of water-binder ratio,fly ash (FA) contents and air-entraining agent on resistance to frost and chloride diffusion of marine concrete blended with FA in natural seawater.The results show that fly ash does not improve the frost resistance of concrete but can improve its resistance to chloride diffusion by addition of less than 30%.The resistance to frost and chloride diffusion of FA concrete can be improved with the decrease of water-binder ratio,and FA may improve both of them simultaneously only being mixed with air-entraining agent.A ratio (named as R) of the frost-resisting durability factor to chloride diffusion coefficient can be used to evaluate the durability of marine concrete.Scanning electron microscope (SEM) analyses are consistent with the evaluations by the value of R.

  1. Determination of nutrients in the presence of high chloride concentrations by column-switching ion chromatography.

    Science.gov (United States)

    Bruno, P; Caselli, M; de Gennaro, G; De Tommaso, B; Lastella, G; Mastrolitti, S

    2003-06-27

    Determination of inorganic anions in waters of high salinity is one of the most difficult task in analytical chemistry. A simple column-switching method, based on an original chromatographic set-up, for the determination of nutrients (nitrate, nitrite and phosphate) in chloride rich aqueous matrices is presented. A pre-separation system (made of two in line pre-columns, Dionex AG9-HC 4 mm) connected to an analytical column (Dionex AS9-HC 4 mm) by a four way pneumatic valve, allows chloride to be eluted off into the waste and nutrients to be separated and detected by a conductimeter and/or a UV spectrophotometer. Neither chemical pre-treatment nor sample dilution are required; sample matrices presenting a large range of chloride concentrations can be investigated. Moreover by using this technology, automation for routine analysis, low analysis time and low costs can be achieved. LODs of 100, 300, 1000 microg/l for nitrate, nitrite and phosphate, respectively, have been obtained by spiking a synthetic sea water sample containing 20,000 mg/l of chloride and 3000 mg/l of sulphate. Analyte calibration curves of analytes are linear (r>0.99) in the range between the LODs and 60 mg/l. This method was applied to nutrients determination in sea water samples collected near a river outlet. PMID:12899303

  2. Effect of alkali and chloride ions on pitting corrosion behaviour of boron added modified 9Cr-1Mo steel

    International Nuclear Information System (INIS)

    Modified 9Cr-1Mo ferritic steel is used as a structural material for the steam generator of Prototype Fast Breeder Reactor (PFBR) due to its high temperature corrosion and oxidation resistance. Since all the components (tube, tube sheet and shell) of steam generator are made of modified 9Cr-1Mo, it is also required to be resistant against general and localized corrosion. Modified 9Cr-1Mo steel with 100 ppm boron addition is being considered as the structural material for the steam generators of future fast reactors, owing to its improved creep properties. In the present work, an attempt has been made to study the pitting corrosion behaviour of this material in alkaline environment containing chloride ions. Alkaline environment was chosen to simulate the caustic condition generated in the steam generator due to the accidental leak of feed water containing chloride ions (as impurity) with hot sodium. Potentiodynamic anodic polarization studies were carried out in deaerated 0.1, 0.2 and 0.5M sodium hydroxide solutions containing 0.1, 0.2 and 0.5M sodium chloride. During the experiments current value was allowed to increase up to 1 mA to ensure that stable pits were developed. Pitting potentials (Epp) were determined from the anodic polarization diagrams. The pitted specimens etched in Villela's reagent were observed under an optical microscope as well as a scanning electron microscope (SEM). Most of the pits observed under optical microscope were found to be hemispherical in nature. The diameters of 30 random pits were measured (two diameters at right angles for each pit) and an average diameter for each pit was calculated

  3. Application of sulphoaluminate cement to repair deteriorated concrete members in chloride ion rich environment-A basic experimental investigation of durability properties

    OpenAIRE

    Cai, Gaochuang; Zhao, Jun

    2016-01-01

    This paper presents a basic experimental investigation of the durability properties of Sulphoaluminate cement concrete (SACC) and Portland Cement Concrete (PCC). It is to discuss the potential application of Sulphoaluminate cement towards the repair of deteriorated concrete members in chloride ion-rich environment such as coastal engineering, using a SACC repair layer with higher strength than original damaged concrete. The chloride-related durability properties of SACCs were comprehensively ...

  4. Hydration of the chloride ion in concentrated aqueous solutions using neutron scattering and molecular dynamics

    Czech Academy of Sciences Publication Activity Database

    Pluhařová, Eva; Fischer, H. E.; Mason, Philip E.; Jungwirth, Pavel

    2014-01-01

    Roč. 112, 9/10 (2014), s. 1230-1240. ISSN 0026-8976 R&D Projects: GA ČR GBP208/12/G016; GA MŠk LH12001 Grant ostatní: GA MŠk(CZ) LM2010005 Institutional support: RVO:61388963 Keywords : lithium * solution * molecular dynamics * chloride * neutron scattering Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.720, year: 2014

  5. Discrete-state model of coupled ion permeation and fast gating in ClC chloride channels

    International Nuclear Information System (INIS)

    A simple discrete-state model of ion permeation through a channel protein is considered in which the flow of ions through the open channel is coupled to the opening/closing of a gate by virtue of configurational changes in a particular pore-lining amino acid residue. The model is designed so as to represent essential features of ClC chloride channels, in which a particular glutamate residue (E148 in bacterial ClC channels) is thought to switch from a conformation that is pinned back (away from the pore itself) to one where this side group blocks the channel at a Cl- binding site. Thus, competition between the gate residue and Cl- ions for this site leads to interesting kinetics, such as the saturation of the gate closing time with increasing concentration of internal Cl- concentration. Analysis of the model proposed here shows that it can account for many qualitative features of ion channel permeation and gate closing rates in ClC-type channels observed experimentally and in recent computer simulations of these processes

  6. Role of Citrate Ions in the Phosphonate-based Inhibitor System for Mild Steel in Aqueous Chloride Media

    Directory of Open Access Journals (Sweden)

    G. Gunasekaran

    2005-01-01

    Full Text Available The corrosion inhibition efficiency of phosphonic acid and its derivatives for the inhibition of corrosion of mild steel in neutral chloride media is decided by its ability to form protectivefilm over the surface. In this context, the effect of addition of metal cations and certain organic compounds, such as citrate in conjugation with phosphonic acid to impart synergistic corrosion inhibition has been explored. The experiments were carried out using various concentrations of trisodium citrate and zinc ions in an aqueous solution of 2-carboxyethyl phosphonic acid (2CEPA at 25 ppm. The corrosion characteristics have been determined using electrochemical impedance spectroscopy together with determination of corrosion rate by weight-loss method. It has been observed that a combination of inhibitive ions, namely citrate, ZCEPA, and zinc ions at 25 ppm gives 96 per cent inhibition efficiency and this corrosion inhibition is due to the formation of a protective film. By increasing the concentration of citrate beyond 25 ppm, the corrosion inhibition efficiency decreases. This paper discusses the role of citrate and zinc ions in imparting added corrosion inhibition ability using 2CEPA on the basis of experimental results.

  7. Effect of temperature on the durability of class C fly ash belite cement in simulated radioactive liquid waste: synergy of chloride and sulphate ions.

    Science.gov (United States)

    Guerrero, A; Goñi, S; Allegro, V R

    2009-06-15

    The durability of class C fly ash belite cement (FABC-2-W) in simulated radioactive liquid waste (SRLW) rich in a mixed sodium chloride and sulphate solution is presented here. The effect of the temperature and potential synergic effect of chloride and sulfate ions are discussed. This study has been carried out according to the Koch-Steinegger test, at the temperature of 20 degrees C and 40 degrees C during a period of 180 days. The durability has been evaluated by the changes of the flexural strength of mortar, fabricated with this cement, immersed in a simulated radioactive liquid waste rich in sulfate (0.5M), chloride (0.5M) and sodium (1.5M) ions--catalogued like severely aggressive for the traditional Portland cement--and demineralised water, which was used as reference. The reaction mechanism of sulphate, chloride and sodium ions with the mortar was evaluated by scanning electron microscopy (SEM), porosity and pore-size distribution, and X-ray diffraction (XRD). The results showed that the chloride binding and formation of Friedel's salt was inhibited by the presence of sulphate. Sulphate ion reacts preferentially with the calcium aluminate hydrates forming non-expansive ettringite which precipitated inside the pores; the microstructure was refined and the mechanical properties enhanced. This process was faster and more marked at 40 degrees C. PMID:19056176

  8. Use of Electrochemical Noise (EN) Technique to Study the Effect of sulfate and Chloride Ions on Passivation and Pitting Corrosion Behavior of 316 Stainless Steel

    Science.gov (United States)

    Pujar, M. G.; Anita, T.; Shaikh, H.; Dayal, R. K.; Khatak, H. S.

    2007-08-01

    In the present paper, studies were conducted on AISI Type 316 stainless steel (SS) in deaerated solutions of sodium sulfate as well as sodium chloride to establish the effect of sulfate and chloride ions on the electrochemical corrosion behavior of the material. The experiments were conducted in deaerated solutions of 0.5 M sodium sulfate as well as 0.5 M sodium chloride using electrochemical noise (EN) technique at open circuit potential (OCP) to collect the correlated current and potential signals. Visual records of the current and potential, analysis of data to arrive at the statistical parameters, spectral density estimation using the maximum entropy method (MEM) showed that sulfate ions were incorporated in the passive film to strengthen the same. However, the adsorption of chloride ions resulted in pitting corrosion thereby adversely affecting noise resistance ( R N). Distinct current and potential signals were observed for metastable pitting, stable pitting and passive film build-up. Distinct changes in the values of the statistical parameters like R N and the spectral noise resistance at zero frequency ( R°SN) revealed adsorption and incorporation of sulfate and chloride ions on the passive film/solution interface.

  9. Separation studies of molybdate and tellurate ions on charcoal impregnated with tin(IV) chloride

    International Nuclear Information System (INIS)

    New charcoal impregnated with tin(IV) chloride adsorbent was prepared. Comparative studies for the adsorption behaviour of Mo(VI) and Te(VI) tracers in HCl and/or HNO3 solutions on activated and impregnated charcoal were carried out using batch technique. The distribution data of Mo(VI) and Te(VI) were discussed and a mechanism for the adsorption of Mo(VI) on impregnated charcoal was suggested. Chromatographic separation of 99Mo(VI) and *Te(VI) from each other with high radiochemical purity was experimentally proved using columns of impregnated charcoal. (orig.)

  10. Lactobacillus casei reduces susceptibility to type 2 diabetes via microbiota-mediated body chloride ion influx

    OpenAIRE

    Yong Zhang; Xiao Guo; Jianlin Guo; Qiuwen He; He Li; Yuqin Song; Heping Zhang

    2014-01-01

    Gut microbiota mediated low-grade inflammation is involved in the onset of type 2 diabetes (T2DM). In this study, we used a high fat sucrose (HFS) diet-induced pre-insulin resistance and a low dose-STZ HFS rat models to study the effect and mechanism of Lactobacillus casei Zhang in protecting against T2DM onset. Hyperglycemia was favorably suppressed by L. casei Zhang treatment. Moreover, the hyperglycemia was connected with type 1 immune response, high plasma bile acids and urine chloride io...

  11. Calcium ion activity in physiological salt solutions: influence of anions substituted for chloride

    DEFF Research Database (Denmark)

    Christoffersen, Gert Rene Juul; Skibsted, Leif H

    1975-01-01

    1. Substitution by different anions for chloride in physiological salt solutions leads to binding between Ca2+ and the anion. Experiments designed to test effects of Cl- therefore often show mixed effects of changes in Cl- and Ca2+ activity.   2. This mixed effect is demonstrated in neurons...... of the snail, Helix pomatia: current-voltage characteristics and membrane potential are described during reduction of extracellular Cl- using different anions as substitutes. Methylsulphate is concluded to be the best substitute in this preparation. 3. The association constants for the binding of Ca2...

  12. 再生混凝土中氯离子渗透性能试验研究%Experimental Study on Chloride Ion Penetration into Recycled Aggregate Concrete

    Institute of Scientific and Technical Information of China (English)

    吴相豪; 岳鹏君

    2011-01-01

    In order to investigate the effects of recycled concrete aggregate, wet and dry cycles, fly ash replacement on chloride ion penetration of recycled aggregate concrete, the chloride ion concentration in recycled aggregate concrete was measured during chloride natural diffusion test. The results show that the a-bility to resist chloride ion penetrate into recycled aggregate concrete is weaker than that for natural aggregate concrete; the resistance to chloride ion penetration into recycled aggregate concrete can be improved by replacing cement with fly ash, 20%(by mass> replacement of cement with fly ash is optimum; the rate . Of chloride ion penetration into recycled aggregate concrete under wet and dry cycles is higher than that into saturated recycled aggregate concrete.%通过氯离子自然扩散试验,测定再生混凝土试件中的氯离子浓度,分析了再生骨料、粉煤灰掺量、全浸泡与干湿循环方式对再生混凝土中氯离子渗透性能的影响.结果表明:再生混凝土抗氯离子渗透能力比普通混凝土差;掺入粉煤灰能提高再生混凝土抗氯离子渗透能力,粉煤灰最佳掺量为20%(质量分数);干湿循环方式可加快再生混凝土中氯离子的渗透速度.

  13. Influence of Blended Cements with Calcareous Fly Ash on Chloride Ion Migration and Carbonation Resistance of Concrete for Durable Structures

    Directory of Open Access Journals (Sweden)

    Michał A. Glinicki

    2016-01-01

    Full Text Available The objective of this paper is to examine the possible use of new blended cements containing calcareous fly ash in structural concrete, potentially adequate for structural elements of nuclear power plants. The investigation included five new cements made with different contents of non-clinker constituents: calcareous fly ash, siliceous fly ash, ground granulated blastfurnace slag, and a reference cement—ordinary Portland cement. The influence of innovative cements on the resistance of concrete to chloride and carbonation exposure was studied. Additionally, an evaluation of the microstructure was performed using optical microscopy on concrete thin sections. Test results revealed a substantial improvement of the resistance to chloride ion penetration into concrete containing blended cements. The resistance was higher for increased clinker replacement levels and increased with curing time. However, concrete made with blended cements exhibited higher depth of carbonation than the Portland cement concrete, except the Portland-fly ash cement with 14.3% of calcareous fly ash. The thin sections analysis confirmed the values of the carbonation depth obtained from the phenolphthalein test. Test results indicate the possible range of application for new cements containing calcareous fly ash.

  14. The electrochemical behaviour study of La3+ ion in fused chlorides bath. The LaNi5 formation

    International Nuclear Information System (INIS)

    The electrochemical behaviour of La3+ ion was studied in fused chlorides bath, with purpose to obtain LaNi5 formation parameters. The lanthanum reduction/reoxidation mechanism and intermetallic compound formation were investigated by cyclic voltammetry, chronopotentiommetry and galvanostatic electrodeposition. The electrolyte employed was eutectic mixture NaCl-KCl (1:1) with anhydrous LaCl3 as solute, since 0,25 mol. L-1 up to 2 mol. L-1, between 700 deg C and 800 deg C. The anhydrous LaCl3 was prepared by lanthanum chloride slow dehydration with HCl flow and heating until 300 deg C. Over molybdenum, results depicted that lanthanum electrochemical behaviour was quasi-reversible and electrodeposition occurred in a charge transfer step with three electrons. In nickel, intermetallic compound formation was observed by interdiffusion. The scanning electronic microscopy (SEM-EDS) and X ray diffraction analysis indicated that layers composition depend on temperature and solute concentration in fused bath. Mainly LaNi5 intermetallic compound was formed with LaCl3 anhydrous concentration of 2 mol. L-1 at 750 deg C, with cathodic current density until 100 mA.cm-2. (author)

  15. About effect of magnesium chloride and some ions in brines on boron coprecipitation by iron hydroxide

    International Nuclear Information System (INIS)

    Studies were made of conditions of precipitation of boron with iron hydroxide from the brines of the mixing zone of the Kara-Bogaz Gol, the mother liquor after the precipitation of potassium salts and artificial manganese chloride solutions at a temperature of 7-45 dee C. The maximum extraction of boron from the brines investigated is observed both in a weakly acid and a weakly alkaline medium. The extraction intensity increases drastically in the range of the maximum with an increase in brine concentration. The anions Cl-, SO42-, and HCO3- present in the brines produce the maximum effect on boron precipitation at a definite pH. This effect depends on the nature of the anions and their ratio in the brine. With a rise in temperature the degree of boron precipitations from the magnesium chloride brine and the precipitate capacity increase as a result of the release of active magnesium hydroxide. When the ratio of Fe2O3 to 100 ml initial solution changes towards increase in precipitating agent at a constant temperature, the precipitate capacity for B2O3 decreases

  16. Ion induced dissociation of tetraphenyl iron(III) porphyrin chloride and electron-capture induced dissociation of protoporphyrin IX ions

    International Nuclear Information System (INIS)

    We performed experiments concerning the fragmentation of different porphyrin molecules. Multi-ionisation and ion-induced fragmentation of FeTPPCl''q''+ (q = 1 to 4) have been studied in slow collisions with multiply charged ions. We have shown also electron-capture induced dissociation of protoporphyrin cations, where two electrons in two successive have been captured in order to convert it to the corresponding even-electron anions. All fragmentation processes are discussed in terms of charge mobility.

  17. The solubility of hydrous thorium(IV) oxide in chloride media: Development of an aqueous ion-interaction model

    International Nuclear Information System (INIS)

    The solubility of hydrous Th(IV) oxide was measured in NaCl solutions ranging in concentration form 0.6 to 3.0 M and in KCl at 0.6 M, over a wide range of hydrogen ion concentration (psub(cH+) 3 to 11)), and over equilibration times extending to more than one year. Our results show solubilities higher (by three to four orders of magnitude) than have been reported by other investigations in NaClO4 media. Our thermodynamic modelling calculations indicate that these differences in solubility are a result of differences in the ionic media and the ionic strength of the solutions. We have used the thermodynamic model of Pitzer and coworkers, which is valid to high ionic strengths, to analyze our data for solubility in both chloride and perchlorate media. The analysis required the use of specific ion-interaction parameters only for the bare Th4+ ion with the bulk anion Cl-. The final thermodynamic model gives a good representation of all of our solubility data in NaCl and KCl solutions below psub(cH+) of ∝ 7 as well as the solubility data in NaClO4 media and the osmotic data for ThCl4 solutions. (orig.)

  18. Cytological comparison of gill chloride cells and blood serum ion concentrations in kutum (Rutilus frisii kutum spawners from brackish (Caspian Sea and fresh water (Khoshkrood River environments

    Directory of Open Access Journals (Sweden)

    Ghahremanzadeh Zahra

    2014-09-01

    Full Text Available The size and number of chloride cells and serum ion concentrations in kutum, Rutillus frisii kutum Nordman, from brackish (Caspian Sea and fresh water (Khoshkrood River environments were studied to gain a better understanding of osmoregulation in this species. Twenty mature kutum specimens were collected from the Caspian Sea (Anzali coasts, 8.49 ppt salinity and 12.4°C temperature and 20 specimens from Khoshkrood River (0.18 ppt salinity and 18°C temperature. Gill samples were analyzed histologically and concentrations of Na+, Cl- , K+, and Mg2+ ions were determined in the blood serum. Concentrations of Na+, Cl- , K+, and Mg2+ ions and osmotic pressure in mature kutum from brackish water were significantly higher than in specimens from fresh water. The average size and number of chloride cells in the fish from seawater were considerably larger than those from fresh water. The mean size of chloride cells was 6.89 ± 1.16 μm in brackish water samples and 5.1 ± 0.81 μm in river samples. The average number of chloride cells in brackish and river water samples were 16.92 and 6.57, respectively. The density and size of chloride cells increased with increases in salinity

  19. Identification of a chloride ion binding site in Na+/Cl−-dependent transporters

    OpenAIRE

    Forrest, Lucy R.; Tavoulari, Sotiria; Zhang, Yuan-Wei; Rudnick, Gary; Honig, Barry

    2007-01-01

    The recent determination of the crystal structure of the leucine transporter from Aquifex aeolicus (aaLeuT) has provided significant insights into the function of neurotransmitter:sodium symporters. Transport by aaLeuT is Cl− independent, whereas many neurotransmitter:sodium symporters from higher organisms depend on Cl− ions. However, the only Cl− ion identified in the aaLeuT structure interacts with nonconserved residues in extracellular loops, and thus the relevance of this binding site is...

  20. Chloride ion effect and alloying effect on dealloying-induced formation of nanoporous AuPt alloy

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yan, E-mail: mse_wangy@ujn.edu.cn; Xu, Junling; Wu, Bo

    2013-07-01

    The dealloying of the rapidly solidified Al{sub 66}Au{sub 23.8}Pt{sub 10.2} precursor in the 5 wt.% HCl or 20 wt.% NaOH solution has been investigated using X-ray diffraction, scanning electron microscopy, energy dispersive X-ray analysis and transmission electron microscopy, in order to clarify the chloride ion effect and alloying effect on the formation of nanoporous Au–Pt alloy. The Al{sub 66}Au{sub 23.8}Pt{sub 10.2} precursor is composed of a single Al{sub 2}Au-type intermetallic compound and only Au(Pt) solid solution can be identified in the as-dealloyed sample. The Pt addition can significantly refine the nanoporous structure during the dealloying of the Al{sub 66}Au{sub 23.8}Pt{sub 10.2} precursor either in the HCl or NaOH solution. Moreover, the alloying effect of Pt markedly exceeds the coarsening effect of chloride ion adsorption for the formation of nanoporous Au–Pt. The average ligament size is 5.2 ± 0.7 and 3.3 ± 0.4 nm for the nanoporous Au–Pt alloy obtained in the HCl and NaOH solution, respectively. In addition, electrochemical measurements including potentiodynamic polarization and cyclic voltammetry have also been performed on the Al{sub 66}Au{sub 23.8}Pt{sub 10.2} precursor.

  1. Changes in cationic selectivity of the nicotinic channel at the rat ganglionic synapse: a role for chloride ions?

    Directory of Open Access Journals (Sweden)

    Oscar Sacchi

    Full Text Available The permeability of the nicotinic channel (nAChR at the ganglionic synapse has been examined, in the intact rat superior cervical ganglion in vitro, by fitting the Goldman current equation to the synaptic current (EPSC I-V relationship. Subsynaptic nAChRs, activated by neurally-released acetylcholine (ACh, were thus analyzed in an intact environment as natively expressed by the mature sympathetic neuron. Postsynaptic neuron hyperpolarization (from -40 to -90 mV resulted in a change of the synaptic potassium/sodium permeability ratio (P(K/P(Na from 1.40 to 0.92, corresponding to a reversible shift of the apparent acetylcholine equilibrium potential, E(ACh, by about +10 mV. The effect was accompanied by a decrease of the peak synaptic conductance (g(syn and of the EPSC decay time constant. Reduction of [Cl(-](o to 18 mM resulted in a change of P(K/P(Na from 1.57 (control to 2.26, associated with a reversible shift of E(ACh by about -10 mV. Application of 200 nM αBgTx evoked P(K/P(Na and g(syn modifications similar to those observed in reduced [Cl(-](o. The two treatments were overlapping and complementary, as if the same site/mechanism were involved. The difference current before and after chloride reduction or toxin application exhibited a strongly positive equilibrium potential, which could not be explained by the block of a calcium component of the EPSC. Observations under current-clamp conditions suggest that the driving force modification of the EPSC due to P(K/P(Na changes represent an additional powerful integrative mechanism of neuron behavior. A possible role for chloride ions is suggested: the nAChR selectivity was actually reduced by increased chloride gradient (membrane hyperpolarization, while it was increased, moving towards a channel preferentially permeable for potassium, when the chloride gradient was reduced.

  2. Effects of chloride ions on electro-coagulation-flotation process with aluminum electrodes for algae removal.

    Science.gov (United States)

    Gao, Shanshan; Du, Maoan; Tian, Jiayu; Yang, Jianyu; Yang, Jixian; Ma, Fang; Nan, Jun

    2010-10-15

    Electro-coagulation-flotation (ECF) is one of the most promising technologies that offers an attractive alternative to conventional coagulation and flotation. In this study, the effectiveness and mechanisms of algae removal by ECF process using aluminum electrodes was investigated in the presence of Cl(-) ions. The results showed that the addition of Cl(-) ions (1.0, 3.0, 5.0 and 8.0 mM) had a promoting effect on the algae removal in terms of both the cell density and chlorophyll-a, which could be attributed to the following two reasons. Firstly, active chlorine could be generated in the ECF when Cl(-) ions were present. The electrochemically generated active chlorine was demonstrated to be effective for the inactivation of algae cells with the aid of the electric field in the ECF. Secondly, the Cl(-) ions in the algae solution could enhance the release of Al(3+) from the aluminum electrodes in the ECF. Through SEM-EDX analysis, pitting corrosion and alleviated formation of oxide film by Cl(-) ions were observed on the anode surface. When considering that Cl(-) ions are universally present in natural waters, the effects of Cl(-) on ECF process for algae removal are of great significance. PMID:20667652

  3. Donnan effect on chloride ion distribution as a determinant of body fluid composition that allows action potentials to spread via fast sodium channels

    Directory of Open Access Journals (Sweden)

    Kurbel Sven

    2011-05-01

    Full Text Available Abstract Proteins in any solution with a pH value that differs from their isoelectric point exert both an electric Donnan effect (DE and colloid osmotic pressure. While the former alters the distribution of ions, the latter forces water diffusion. In cells with highly Cl--permeable membranes, the resting potential is more dependent on the cytoplasmic pH value, which alters the Donnan effect of cell proteins, than on the current action of Na/K pumps. Any weak (positive or negative electric disturbances of their resting potential are quickly corrected by chloride shifts. In many excitable cells, the spreading of action potentials is mediated through fast, voltage-gated sodium channels. Tissue cells share similar concentrations of cytoplasmic proteins and almost the same exposure to the interstitial fluid (IF chloride concentration. The consequence is that similar intra- and extra-cellular chloride concentrations make these cells share the same Nernst value for Cl-. Further extrapolation indicates that cells with the same chloride Nernst value and high chloride permeability should have similar resting membrane potentials, more negative than -80 mV. Fast sodium channels require potassium levels >20 times higher inside the cell than around it, while the concentration of Cl- ions needs to be >20 times higher outside the cell. When osmotic forces, electroneutrality and other ions are all taken into account, the overall osmolarity needs to be near 280 to 300 mosm/L to reach the required resting potential in excitable cells. High plasma protein concentrations keep the IF chloride concentration stable, which is important in keeping the resting membrane potential similar in all chloride-permeable cells. Probable consequences of this concept for neuron excitability, erythrocyte membrane permeability and several features of circulation design are briefly discussed.

  4. Cytoplasmic pathway followed by chloride ions to enter the CFTR channel pore.

    Science.gov (United States)

    El Hiani, Yassine; Negoda, Alexander; Linsdell, Paul

    2016-05-01

    Most ATP-binding cassette (ABC) proteins function as ATP-dependent membrane pumps. One exception is the cystic fibrosis transmembrane conductance regulator (CFTR), an ABC protein that functions as a Cl(-) ion channel. As such, the CFTR protein must form a continuous pathway for the movement of Cl(-) ions from the cytoplasm to the extracellular solution when in its open channel state. Extensive functional investigations have characterized most parts of this Cl(-) permeation pathway. However, one region remains unexplored-the pathway connecting the cytoplasm to the membrane-spanning pore. We used patch clamp recording and extensive substituted cysteine accessibility mutagenesis to identify amino acid side-chains in cytoplasmic regions of CFTR that lie close to the pathway taken by Cl(-) ions as they pass from the cytoplasm through this pathway. Our results suggest that Cl(-) ions enter the permeation pathway via a single lateral tunnel formed by the cytoplasmic parts of the protein, and then follow a fairly direct central pathway towards the membrane-spanning parts of the protein. However, this pathway is not lined continuously by any particular part of the protein; instead, the contributions of different cytoplasmic regions of the protein appear to change as the permeation pathway approaches the membrane, which appears to reflect the ways in which different cytoplasmic regions of the protein are oriented towards its central axis. Our results allow us to define for the first time the complete Cl(-) permeation pathway in CFTR, from the cytoplasm to the extracellular solution. PMID:26659082

  5. Effect of the chloride ions on the hydrolysis of praseodymium in a 2M ion force media

    International Nuclear Information System (INIS)

    The constants of the product of solubility and the first of hydrolysis were determined of the Praseodymium in media 2M of NaClO4 and 2M of NaCl, to 303 K and under conditions free of CO2. The diagram of solubility was obtained (pPr(ac) - pCH), by means of a radiochemical method and with it was established the pCH that limit the saturation and non saturation areas; that diagram allowed, also, to calculate the constant of the product of solubility. Also, it was adjusted with the polynomial of solubility equation, that it allowed to determine and to check the values of the constants of the product of solubility and the first of hydrolysis. Independently, it was determined the first constant of hydrolysis of the element, by means of potentiometric titrations whose data were treated with the computer program named SUPERQUAD and with the adjustment of the equation of the average number of bonds. It was also calculates the log constant βPr,Cl of the specie PrCI2+ starting from the hydrolysis constants obtained in the perchlorate and chloride media. (Author)

  6. Optimization of Preparation of Activated Carbon from Ricinus communis Leaves by Microwave-Assisted Zinc Chloride Chemical Activation: Competitive Adsorption of Ni2+ Ions from Aqueous Solution

    Directory of Open Access Journals (Sweden)

    M. Makeswari

    2013-01-01

    Full Text Available The preparation of activated carbon (AC from Ricinus communis leaves was investigated in this paper. Orthogonal array experimental design method was used to optimize the preparation of AC using microwave assisted zinc chloride. Optimized parameters were radiation power of 100 W, radiation time of 8 min, concentration of zinc chloride of 30% by volume, and impregnation time of 24 h, respectively. The surface characteristics of the AC prepared under optimized conditions were examined by pHZPC, SEM-EDAX, XRD, and FTIR. Competitive adsorption of Ni2+ ions on Ricinus communis leaves by microwave assisted zinc chloride chemical activation (ZLRC present in binary and ternary mixture was compared with the single metal solution. The effects of the presence of one metal ion on the adsorption of the other metal ion were investigated. The experimental results indicated that the uptake capacity of one metal ion was reduced by the presence of the other metal ion. The extent of adsorption capacity of the binary and ternary metal ions tested on ZLRC was low (48–69% as compared to single metal ions. Comparisons with the biosorption of Ni2+ ions by the biomass of ZLRC in the binary (48.98–68.41%-~Ni-Cu and 69.76–66.29%-~Ni-Cr and ternary solution (67.32–57.07%-~Ni–Cu and Cr could lead to the conclusion that biosorption of Ni2+ ions was reduced by the influence of Cu2+ and Cr3+ ions. The equilibrium data of the adsorption was well fitted to the Langmuir isotherm. The adsorption process follows the pseudo-second-order kinetic model.

  7. Diffusion of Chloride Ions in Soils: Ⅰ.Influences of Soil Moisture,Bulk Density and Temperature

    Institute of Scientific and Technical Information of China (English)

    XUMINGGANG; ZHANGYIPING; 等

    1997-01-01

    Diffusion coefficients of chlorde ions in four soils of different exture with varying effective moisture content and varying bulk density from 1.1 to 1.6 g cm3 under three different temperatures were determined by the diffusion-cell method using 36Cl-labelled CaCl2 solution.The result showed that activation energy decreased with water content,which indicated that the threshold fro diffusion was lower at a higher soil moisture rate .Therefor,the diffusion coefficient(D) of chloride ions in soil increased consistently with soil moisture,Although a near linear increase in the diffusion coefficient with increasing soil moisture or bulk density in all the soils was observed,the increase rate in different soils was not the same.The D value increased with teperature,and with temperature increased by 10℃ in the range from 5℃to 45℃ the D valve increased by 10%-30%,averaging about 20%.

  8. Simultaneous determination of fluoride, chloride, sulfate, phosphate,monofluorophosphate, glycerophosphate, sorbate, and saccharin in gargles by ion chromatography

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yan-zhen; ZHOU Yan-chun; LIU Li; ZHU Yan

    2007-01-01

    Simple, reliable and sensitive analytical methods to determine anticariogenic agents, preservatives, and artificial sweeteners contained in commercial gargles are necessary for evaluating their effectiveness, safety, and quality. An ion chromatography (IC) method has been described to analyze simultaneously eight anions including fluoride, chloride, sulfate, phosphate,monofluorophosphate, glycerophosphate (anticariogenic agents), sorbate (a preservative), and saccharin (an artificial sweetener)in gargles. In this IC system, we applied a mobile phased gradient elution with KOH, separation by IonPac AS18 columns, and suppressed conductivity detection. Optimized analytical conditions were further evaluated for accuracy. The relative standard deviations (RSDs) of the inter-day's retention time and peak area of all species were less than 0.938% and 8.731%, respectively,while RSDs of 5-day retention time and peak area were less than 1.265% and 8.934%, respectively. The correlation coefficients for targeted analytes ranged from 0.999 7 to 1.000 0. The spiked recoveries for the anions were 90%~102.5%. We concluded that the method can be applied for comprehensive evaluation of commercial gargles.

  9. Separation and preconcentration of cadmium ions using octadecyl silica membrane disks modified by methyltrioctylammonium chloride

    Energy Technology Data Exchange (ETDEWEB)

    Haji Shabani, Ali Mohammad; Dadfarnia, Shayesteh; Motavaselian, Fatemeh [Department of Chemistry, Yazd University, Yazd 89195-741 (Iran, Islamic Republic of); Ahmadi, Seyyed Hamid [Chemistry and Chemical Engineering Research Center of Iran, 14335-186 Tehran (Iran, Islamic Republic of)], E-mail: ahmadi@ccerci.ac.ir

    2009-02-15

    A simple and selective method for the determination of cadmium in water samples by FAAS after solid phase extraction has been developed. The method is based on the sorption of cadmium as CdI{sub 4}{sup 2-} on octadecyl silica membrane disks modified by cationic surfactant of methyltrioctylammonium chloride in the pH range of 1-8. The sorbed cadmium is then eluted with 10 ml of 1 mol l{sup -1} nitric acid in ethanol and is measured by flame atomic absorption spectrometry. The influence of flow rates of eluent and sample solution, iodide concentration and amount of surfactant in retention and elution of cadmium from disks was also investigated. A preconcentration factor of 100 was achieved by passing 1000 ml of sample through the membrane disk. The limit of detection (LOD) of cadmium was found to be 0.014 ng ml{sup -1}. Precision at 2.5 {mu}g l{sup -1} was 1.2% (n = 8). The method was successfully applied to the determination of cadmium in some natural water samples. The accuracy was assessed through recovery experiment, independent analysis by graphite furnace atomic absorption spectrometry, and analysis of certified reference waters.

  10. Separation and preconcentration of cadmium ions using octadecyl silica membrane disks modified by methyltrioctylammonium chloride

    International Nuclear Information System (INIS)

    A simple and selective method for the determination of cadmium in water samples by FAAS after solid phase extraction has been developed. The method is based on the sorption of cadmium as CdI42- on octadecyl silica membrane disks modified by cationic surfactant of methyltrioctylammonium chloride in the pH range of 1-8. The sorbed cadmium is then eluted with 10 ml of 1 mol l-1 nitric acid in ethanol and is measured by flame atomic absorption spectrometry. The influence of flow rates of eluent and sample solution, iodide concentration and amount of surfactant in retention and elution of cadmium from disks was also investigated. A preconcentration factor of 100 was achieved by passing 1000 ml of sample through the membrane disk. The limit of detection (LOD) of cadmium was found to be 0.014 ng ml-1. Precision at 2.5 μg l-1 was 1.2% (n = 8). The method was successfully applied to the determination of cadmium in some natural water samples. The accuracy was assessed through recovery experiment, independent analysis by graphite furnace atomic absorption spectrometry, and analysis of certified reference waters

  11. Geometric isotope effects on small chloride ion water clusters with path integral molecular dynamics simulations

    International Nuclear Information System (INIS)

    Highlights: • PIMD simulations with PM6-DH+ potential are carried out for Cl−(H2O)n clusters. • The geometric isotope effects on the rearrangement of single and multi shell structures are presented. • The competition of intramolecular and intermolecular nuclear quantum effects on the cluster structures is shown. • The correlations between r(Cl…O) and other vibration motions are discussed. - Abstract: The geometric isotope effects on the structures of hydrated chloride ionic hydrogen bonded clusters are explored by carrying out path integral molecular dynamics simulations. First, an outer shell coordinate is selected to display the rearrangement of single and multi hydration shell cluster structures. Next, to show the competition of intramolecular and intermolecular nuclear quantum effects, the intramolecular OH∗ stretching and intermolecular ion–water wagging motions are studied for single and multi shell structures, respectively. The results indicate that the intermolecular nuclear quantum effects stabilize the ionic hydrogen bonds in single shell structures, while they are destabilized through the competition with intramolecular nuclear quantum effects in multi shell structures. In addition, the correlations between ion–water stretching motion and other cluster vibrational coordinates are discussed. The results indicate that the intermolecular nuclear quantum effects on the cluster structures are strongly related to the cooperation of the water–water hydrogen bond interactions

  12. Determination of fluoride and chloride in nickel ore by ion chromatography%离子色谱法测定镍矿中氟和氯

    Institute of Scientific and Technical Information of China (English)

    窦怀智; 陆彩霞; 侯晋

    2012-01-01

    The simultaneous determination of fluoride and chloride contents in nickel ore by ion chromatography was established. The sample was decomposed by H2SO4. After water steam distillation at 160-180℃, the fluoride and chloride in testing solution would be released and absorbed by NaOH so-lution, realizing the separation from matrix and other elements. Then, the contents of fluoride and chloride were determined by ion chromatography. The high-capacity IonPac? AS23 anion separation column (4 mm×250 mm) and IonPac? AG23 protection column (4 mm×50 mm) were used as chro-matographic column and 20 mmol/L NaOH solution was used as eluent. Fluoride and chloride were detected with conductivity detector. The results showed that the peak area of fluoride and chloride had good linear relationship with their contents in the range of 1-25 μg/mL. The correlation coefficients ? were 1. 000 0 and 0. 999 6 for fluoride and chloride respectively. The determination results of fluoride and chloride in sample showed high precision. The recoveries of standard addition were all greater than 95%.%建立了同时测定镍矿中氟、氯含量的离子色谱法.试样经硫酸分解后,在160~180℃的温度下进行水蒸气蒸馏,试液中的氟和氯随着水蒸气逸出并被NaOH吸收液吸收,与基体和其他元素分离,吸收液中的氟和氯用离子色谱法测定.以高容量IonPac(R) AS23型阴离子分离柱(4 mm×250 mm)和IonPac(R) AG23型保护柱(4mm×50 mm)为色谱柱,20 mmol/LNaOH溶液为淋洗液,用电导检测器检测.结果表明,氟和氯含量在1~25μg/mL范围内与相应的峰面积呈良好的线性关系,相关系数(R)分别为1.000 0和0.999 6,样品中氟、氯测定结果具有较高精密度,加标回收率均达到95%以上.

  13. Exchange of uranium (6) ions on nitrogen-phosphorus-containing polyampholytes in chloride-fluoride solutions

    International Nuclear Information System (INIS)

    Uranium sorption from UO2Cl2 solutions containing HCl, NH4Cl and HF by polyampholytes ANKF-1, ANKF-2 and ANKF-3G is investigated. Effect of HCl, NH4Cl and HF in a wide concentration range is shown. On the basis of data on the sorption, results of analysis and IR spectroscopy conclusions are made on the composition of the ions sorbed and forms of their bond with functional groups. Mathematical model of the sorption process is suggested

  14. Solvated Positron Chemistry. The Reaction of Hydrated Positrons with Chloride Ions

    DEFF Research Database (Denmark)

    Mogensen, O. E.; Shantarovich, V. P.

    1974-01-01

    The reaction of hydrated positrons (caq+ with cloride ions in aqueous solutions has been studied by means of positron annihilation angular correlation measurements. A rate constant of k = (2.5 ± 0.5) × 1010 M−1 s−1 was found. Probably the reacting positrons annihilated from an e+ Cl− bound state ...... resulting in an angular correlation curve 8% narrower than for the hydrated positron. Carbontetrachloride in benzene seems to give similar, but smaller effect....

  15. Increasing Ubiquitin Ion Resistance to Unfolding in the Gas Phase Using Chloride Adduction: Preserving More "Native-Like" Conformations Despite Collisional Activation.

    Science.gov (United States)

    Wagner, Nicole D; Kim, Doyong; Russell, David H

    2016-06-01

    Electrospray ionization (ESI) of ubiquitin from acidified (0.1%) aqueous solution produces abundant ubiquitin-chloride adduct ions, [M + nH + xCl]((n - x)+), that upon mild heating react via elimination of neutral HCl. Ion mobility collision cross section (CCS) measurements show that ubiquitin ions retaining chloride adducts exhibit CCS values similar to those of the "native-state" of the protein. Coupled with results from recent molecular dynamics (MD) simulations for the evolution of a salt-containing electrospray droplet, this study provides a more complete picture for how the presence of salts affects the evolution of protein conformers in the final stages of dehydration of the ESI process and within the instrument. PMID:27137645

  16. The corrosive influence of chloride ions preference adsorption on α-Al2O3 (0 0 0 1) surface

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • The preference adsorption and interaction of Cl− at increasing monolayer coverage on Al2O3 in solution environment are modeling by DFT with COSMO. • A redefinition critical one plane monolayer of Cl− is 3/7, and the adsorption energy decrease in three steps, each adsorption energy step only relate to the adsorption site and the morphology. • The weaker interaction between Cl− and Al2O3 surface but stronger interactions between three Cl− make the electrons uniformly occupy on the energy levels of three ions. - Abstract: Conductor-like screening model (COSMO), Periodic DFT calculations have been performed on a Al2O3 surface to model the influence of preference adsorption and interaction of chloride ions at increasing monolayer coverage on undefective passive film on Aluminum in solution environment. The results evidence that the critical monolayer of Cl− is 3/7, which is redefined. With increasing Cl− adsorption, both the first and second Cl− move from Al(1) atop and bridge10 sites to O(5) sites, suggesting that the weaker interaction between Cl− and Al2O3 surface but stronger interactions between three ions make the electrons uniformly occupy on the energy levels of them. More calculations shows that the preference adsorption sites of Cl− are independent of the surface area of oxide, and the adsorption energy decrease in three steps, each adsorption energy step only relate to the adsorption site and the morphology. On undefective oxide film, low coverage Cl− adsorption would restrain surface breakdown to happen which is consistent with the experiment results

  17. Uranium (VI) ion exchange on nitrogen-phosphorus-containing polyampholytes in chloride-fluoride solutions

    Energy Technology Data Exchange (ETDEWEB)

    Pakholkov, V.S.; Denisova, L.A.; Richkov, V.A.; Roshchepkina, L.I.

    1988-09-01

    The adsorption of uranium form UO/sub 2/Cl/sub 2/ solutions containing HCl, NH/sub 4/Cl, and HF has been studied using polyampholyte resins ANKF-1, ANKF-2, and ANKF-3D. The effects of HCl, NH/sub 4/Cl, and HF over broad concentration ranges on uranium adsorption have also been investigated. Based on adsorption data and the results of elemental analysis and IR spectroscopy conclusions have been drawn concerning the composition of adsorbed ions and their binding forms with functional groups. A mathematical model to describe the adsorption process has been proposed.

  18. Chloride ion transport and fate in oilfield wastewater reuse by interval dynamic multimedia aquivalence model.

    Science.gov (United States)

    Hu, Y; Zhang, C; Wang, D Z; Wen, J Y; Chen, M H; Li, Y

    2013-01-01

    A surface flow constructed wetland was built up to dispose of oilfield wastewater with a high level of inorganic salt ions. Chlorine ion (Cl(-)) was selected as an indicator of soil secondary salinization, and an interval dynamic multimedia aquivalence (IDMA) model was developed to investigate the dynamic multimedia environmental (air, water, soil, flora, and groundwater) effects of Cl(-) in the wastewater irrigation process between 2002 and 2020. The modeled Cl(-) concentrations were in good agreement with the measured ones, as indicated by the interval average logarithmic residual errors (IALREs) being generally lower than 0.5 logarithmic units. The model results showed that the temporal trends of Cl(-) concentrations in the multimedia environments represented a relatively steady state. More than 97.00% of the mass exchange was finished between soil and groundwater compartments, and Cl(-) finally outputted the environmental system by the pathways of advection outflows in the water (71.03%) and groundwater (24.02%). Soil (59.17%) was the dominant sink of Cl(-). It was revealed that the high level of Cl(-) in oilfield wastewater was well treated by the constructed wetland, and there was not a significant environmental effect of soil secondary salinization in the oilfield wastewater reused for the constructed wetland irrigation. PMID:23202569

  19. The role of Mg2+ ions in the corrosion behaviour of AA2024-T3 aluminium alloys immersed in chloride-containing environments

    International Nuclear Information System (INIS)

    It is well-known the harmful impact of chloride ions in the corrosion behaviour of aluminium and its alloys. The present work investigates the use of Mg2+ ions as corrosion inhibitors of AA2024-T3 samples immersed in chloride-containing electrolytes. AA2024-T3 samples were immersed into an electrolyte containing chloride ions, in absence or presence of Mg2+. The electrochemical behaviour was studied by potentiondynamic polarization and electrochemical impedance spectroscopy techniques. The results showed the beneficial effects afforded by the Mg2+ ions. First, the open circuit potential was shifted towards more cathodic values and, on the other hand, the impedance values obtained for samples tested in presence of Mg2+ were higher, suggesting a slowdown of the corrosion rate. The morphological characterization was performed using scanning electron microscopy and energy dispersive X-ray spectroscopy. The results demonstrated that the presence Mg2+ hinders Mg dealloying of the S phase particles, which delays their change from anodic to cathodic behaviour, so delaying the subsequent Al matrix galvanic attack. An additional protection mechanism is related to the blockage of cathodic areas by the precipitation of Mg(OH)2 in alkaline environments

  20. Effect of Chloride ion and Zirconium hydride on thr corrosion and SCC behaviors of functionally graded Zirconium alloy p.683

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Y. [Department of Metallurgical and Materials Engineering, Sunmoon University, Asam (Korea, Republic of); Kim, B. G.; Lee, J. W.; Kang, Y. H. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2000-07-01

    Effect of chloride ion and zirconium hydride on the corrosion and stress corrosion cracking behaviors of functionally graded zirconium alloy was studied to develop an advanced nuclear cladding tubing. The functionally graded zirconium alloy had composition gradient of niobium, which was prepared with a hot pressing followed by cold deformation. The corrosion rates and potentials decreased with increasing FeCl{sub 3} and hydride content. The corrosion potentials before and after hydriding are -4.3 V{sub SHE}, 8.8x10{sup -5} A{sub cm}{sup -2} and -12.5 V{sub SHE}, 3.9x10{sup -4} A{sub cm}{sup -2}, respectively. The stress corrosion cracking susceptibility decreased with elongation rate, indicating the saturation value at 5x10{sup -7} sec{sup -1}. SEM observation showed that brittle fracture with corrosion products and pits were observed on the failed surface of hydrided zirconium alloy, suggesting anodic dissolution occurred during exposure after cracking growth along zirconium hydrides. (author)

  1. Kinetic and equilibrium studies of the removal of cadmium ions from acidic chloride solutions by hydrophobic pyridinecarboxamide extractants

    International Nuclear Information System (INIS)

    Liquid-liquid extraction of cadmium(II) from acidic chloride solutions was carried out with alkyl derivatives of pyridinecarboxamide in toluene with addition of 2-ethylhexan-1-ol as modifier. Equilibrium as well as kinetic studies was performed. The kinetic studies of a Cd(II) extraction process were carried out with a Lewis cell having a constant interfacial area. Cadmium(II) concentration in the aqueous phases was determined by atomic absorption spectroscopy (Varian SPECTR AA800). The results of equilibrium experiments showed that cadmium(II) was quantitatively extracted with N,N-dihexylpyridine-3-carboxamide whereas the derivative N,N-dihexylpyridine-2-carboxamide was not able to transfer Cd(II) ions from the aqueous phase to the organic one. Thus, the kinetics of extraction and the initial extraction rate were examined only in the systems with N,N-dihexylpyridine-3-carboxamide. The obtained experimental data as well as the calculated values of mass transfer coefficients suggest that the investigated process of extraction of Cd(II) by means of pyridinecarboxamide as extractant occurs in the mixed diffusion-kinetic region. Moreover, the results of adsorption studies indicated that the extraction of Cd(II) with a hydrophobic extractant should be considered as an interfacial process.

  2. Chloride ions promoted the catalytic wet peroxide oxidation of phenol over clay-based catalysts.

    Science.gov (United States)

    Zhou, Shiwei; Zhang, Changbo; Xu, Rui; Gu, Chuantao; Song, Zhengguo; Xu, Minggang

    2016-01-01

    Catalytic wet peroxide oxidation (CWPO) of phenol over clay-based catalysts in the presence and absence of NaCl was investigated. Changes in the H2O2, Cl(-), and dissolved metal ion concentration, as well as solution pH during phenol oxidation, were also studied. Additionally, the intermediates formed during phenol oxidation were detected by liquid chromatography-mass spectroscopy and the chemical bonding information of the catalyst surfaces was analyzed by X-ray photoelectron spectroscopy (XPS). The results showed that the presence of Cl(-) increased the oxidation rate of phenol to 155%, and this phenomenon was ubiquitous during the oxidation of phenolic compounds by H2O2 over clay-based catalysts. Cl(-)-assisted oxidation of phenol was evidenced by several analytical techniques such as mass spectroscopy (MS) and XPS, and it was hypothesized that the rate-limiting step was accelerated in the presence of Cl(-). Based on the results of this study, the CWPO technology appears to be promising for applications in actual saline phenolic wastewater treatment. PMID:26942523

  3. Why are ionic liquid ions mainly associated in water? A Car-Parrinello study of 1-ethyl-3-methyl-imidazolium chloride water mixture

    Science.gov (United States)

    Spickermann, C.; Thar, J.; Lehmann, S. B. C.; Zahn, S.; Hunger, J.; Buchner, R.; Hunt, P. A.; Welton, T.; Kirchner, B.

    2008-09-01

    In this study we present the results of a first principles molecular dynamics simulation of a single 1-ethyl-3-methyl-imidazolium chloride [C2C1im][Cl] ion pair dissolved in 60 water molecules. We observe a preference of the in plane chloride coordination with respect to the cation ring plane as compared to the energetic slightly more demanding on top coordination. Evaluation of the different radial distribution functions demonstrates that the structure of the hydration shell around the ion pair differs significantly from bulk water and that no true ion pair dissociation in terms of completely autonomous solvation shells takes place on the timescale of the simulation. In addition, dipole moment distributions of the solvent in distinct solvation shells around different functional parts of the [C2C1im][Cl] ion pair are calculated from maximally localized Wannier functions. The analysis of these distributions gives evidence for a depolarization of water molecules close to the hydrophobic parts of the cation as well as close to the anion. Examination of the angular distribution of different OH(H2O )-X angles in turn shows a linear coordination of chloride accompanied by a tangential orientation of water molecules around the hydrophobic groups, being a typical feature of hydrophobic hydration. Based on these orientational aspects, a structural model for the obvious preference of ion pair association is developed, which justifies the associating behavior of solvated [C2C1im][Cl] ions in terms of an energetically favorable interface between the solvation shells of the anion and the hydrophobic parts of the cation.

  4. Photochemical transformation of 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) in surface coastal waters: Effects of chloride and ferric ions

    International Nuclear Information System (INIS)

    Highlights: • Chloride ion promoted the phototransformation of BDE-47 in Fe(III) solution. • In Fe(III) solution, the added Cl− could influence the generation of ·OH. • The chlorinated PBDEs were found in Fe(III) + Cl− solution under irradiation. • These results showed the likely fate of PBDEs in the marine environment. - Abstract: The effects of several aquatic environmental factors on the photochemical transformation of 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) have been investigated. Ferric ion (Fe(III)) has been found to promote the phototransformation of BDE-47, and this process is further enhanced with the added chloride ion (Cl−), while it is suppressed with increasing pH. Electron spin resonance results show that the formation of hydroxyl radical, and the added Cl− could influence the generation of hydroxyl radical in Fe(III) solution. Hence, Cl− enhances the phototransformation of BDE-47 most probably because of the reaction with Fe(III) species under irradiation, yielding hydroxyl and chloride radicals. These radicals can not only decompose PBDEs, but also lead to their photodebromination and photochlorination. These results indicate that the aquatic environmental factors and Cl− in particular played an important role in the photochemical transformation process of PBDEs, providing insight into the likely fate of PBDEs in the marine environment

  5. Mass transport in aqueous zinc chloride-potassium chloride electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Leaist, D.G.

    1986-09-01

    Conductimetric and diaphragm cell techniques have been used to measure ternary diffusion coefficients for aqueous zinc chloride-potassium chloride solutions at 25/sup 0/C. At low concentrations where Zn/sup 2 +/ is the major zinc-transporting species, the diffusion-induced electric field along zinc chloride concentration gradients drives large co-current flows of potassium chloride. In concentrated solutions where a large proportion of zinc diffusses as anionic ZnCl/sub 3//sup -/ and ZnCl/sub 4//sup 2 -/ complexes, flow of zinc chloride generates counterflow of potassium chloride. If a sharp zinc chloride is formed in an otherwise uniform solution of potassium chloride, coupled diffusion can concentrate potassium ions within the diffusion boundary. Equations are developed to predict multicomponent transport coefficients for zinc chloride in supporting electrolytes.

  6. Investigation of the extraction equilibrium of ternary ion-association complexes of thallium(III) with monotetrazolium salts triphenyltetrazolium chloride and thiazolyl blue

    International Nuclear Information System (INIS)

    The extraction equilibrium of ternary ion-association complexes obtained during the reaction of tetrachloride complex of thallium(III) and monotetrazolium salts triphenyltetrazolium chloride (TTC) or thiazolyl blue (MTT) has been studied. The optimum conditions required for the investigations have been found. As a result of using a developed chemical model, the constants of extraction, distribution and association, the distribution coefficients and the recovery factor of the investigated ion-assocates have been determined radiochemically, by means of thallium 204 radiotracer technique. (author)

  7. Removal of copper (II) from aqueous solutions by flotation using polyaluminum chloride silicate (PAX-XL60 S) as coagulant and carbonate ion as activator.

    Science.gov (United States)

    Ghazy, S E; Mahmoud, I A; Ragab, A H

    2006-01-01

    Flotation is a separation technology for removing toxic heavy metal ions from aqueous solutions. Here a simple and rapid flotation procedure is presented for the removal of copper(II) from aqueous solutions. It is based on the use of polyaluminum chloride silicate (PAX-XL60 S) as coagulant and flocculent, carbonate ion as activator and oleic acid (HOL) as surfactant. Both ion and precipitate flotation are included depending on the solution pH. Ion and precipitate flotation in the aqueous HOL-PAX-XL60 S-Cu2+-CO3(2-) system gave powerful preferential removal of Cu2+ (F -100%) over the HOL-PAX-XL60 S-Cu2+ system containing no CO3(2+) ion (F approximately 86%). The role of CO3(2-) ion is also evident from decreasing the dose of PAX-XL60 S from 700 mg l(-1) to 200 mg l(-1). The other parameters, influencing the flotation process, namely: metal ion, surfactant and PAX-XL60 S concentrations, ionic strength, temperature and foreign ions were examined. Moreover, the procedure was successfully applied to recover Cu2+ ions from different volumes up to 11 and from natural water samples. PMID:16457175

  8. Role of Chloride Ion and Dissolved Oxygen in Electrochemical Corrosion of AA5083-H321 Aluminum-Magnesium Alloy in NaCl Solutions under Flow Conditions

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Flow-induced corrosion consists electrochemical and mechanical components. The present paper has to assessed the role of chloride ion and dissolved oxygen in the electrochemical component of flow induced corrosion for AA5083-H321 aluminum-magnesium alloy which is extensively used in the construction of high-speed boats, submarines, hovercrafts, and desalination systems, in NaCl solutions. Electrochemical tests were carried out at flow velocities of 0, 2, 5, 7 and 10 m/s, in aerated and deaerated NaCl solutions with different sodium chloride concentrations. The results showed that the high rate of oxygen reduction under hydrodynamic conditions causes an increase in the density of pits on the surface. The increase of chloride ions concentration under flow conditions accelerates the rate of anodic reactions, but have no influence on the cathodic reactions. Thus, in the current work, it was found that under flow conditions, due to the elimination of corrosion products inside the pits, corrosion resistance of the alloy is increased.

  9. The synergistic inhibition between 8-hydroxyquinoline and chloride ion for the corrosion of cold rolled steel in 0.5 M sulfuric acid

    International Nuclear Information System (INIS)

    The corrosion inhibition of cold rolled steel in 0.5 M sulfuric acid in the presence of 8-hydroxyquinoline and sodium chloride (NaCl) has been investigated by using weight loss and electrochemical techniques. The inhibition efficiency increases with increasing concentration of 8-hydroxyquinoline at the same temperature, but decreases with increasing temperature studied. A synergistic effect exists when 8-hydroxyquinoline and chloride ions are used together to prevent cold rolled steel corrosion in 0.5 M sulfuric acid at every experimental temperature. The polarization curves show that 8-hydroxyquinoline is a cathodic inhibitor, while the complex of 8-hydroxyquinoline and NaCl is a mixed-type inhibitor. The experimental results suggested that the presence of chloride ions in the solution stabilizes the adsorption of 8-hydroxyquinoline molecules on the metal surface and improved the inhibition efficiency of 8-hydroxyquinoline. The adsorption of single 8-hydroxyquinoline follows the Temkin adsorption isotherm, but the complex accords with the Langmuir adsorption isotherm. Some thermodynamic parameters such as adsorption heat, adsorption entropy and adsorption free energy have been calculated by employing thermodynamic equations. Kinetic parameters such as apparent activation energy and pre-exponential factor have been calculated and discussed

  10. A comparison of 95 MeV oxygen ions and 60Co gamma irradiation effect on nonlinear optical L-alanine cadmium chloride single crystals

    International Nuclear Information System (INIS)

    Single crystal of nonlinear optical (NLO) material L-alanine cadmium chloride (LACC) was grown by slow evaporation method at room temperature. The grown crystals were irradiated with 95 MeV oxygen ions and 60Co gamma radiation at doses of 1 Mrad and 6 Mrad. The structural, chemical, dielectric properties, AC and DC conductivity, refractive index of the crystals were studied before and after irradiation. There is a slight change in the lattice parameters due to compressive strain field generated in the irradiated crystals. The observed increase in dielectric constant was found to be more for 60Co gamma irradiated crystals than 95 MeV oxygen ion irradiated crystal. A considerable change in the values of refractive indices was observed for both gamma and ion irradiated crystals. The AC and DC conductivity was found to increase after irradiation. (author)

  11. Electrochemical oxidation of acid black 210 dye on the boron-doped diamond electrode in the presence of phosphate ions: Effect of current density, pH, and chloride ions

    International Nuclear Information System (INIS)

    The electrochemical oxidation of acid black 210 dye (AB-210) on the boron-doped diamond (BDD) was investigated under different pH conditions. The best performance for the AB-210 oxidation occurred in alkaline phosphate solution. This is probably due to oxidizing agents such as phosphate radicals and peroxodiphosphate ions, which can be electrochemically produced with good yields on the BDD anode, mainly in alkaline solution. Under this condition, the COD (chemical oxygen demand) removal was higher than that obtained from the model proposed by Comninellis. Electrolyses performed in phosphate buffer and in the presence of chloride ions resulted in faster COD and color removals in acid and neutral solutions, but in alkaline phosphate solution, a better performance in terms of TOC removal was obtained in the absence of chloride. Moreover, organochloride compounds were detected in all electrolyses performed in the presence of chloride. The AB-210 electrooxidation on BDD using phosphate as supporting electrolyte proved to be interesting since oxidizing species generated from phosphate ions were able to completely degrade the dye without producing organochloride compounds.

  12. Chloride binding of cement-based materials subjected to external chloride environment - A review

    OpenAIRE

    Yuan, Q.; Shi, C; Schutter, G. de; Audenaert, K.; Deng, D.

    2009-01-01

    This paper reviews the chloride binding of cement-based materials subjected to external chloride environments. Chloride ion exist either in the pore solution, chemically bound to the hydration products, or physically held to the surface of the hydration products. Chloride binding of cement-based material is very complicated and influenced by many factors, such as chloride concentration, cement composition, hydroxyl concentration, cation of chloride salt, temperature, supplementary cementing m...

  13. Effect of Glass Powder on Chloride Ion Transport and Alkali-aggregate Reaction Expansion of Lightweight Aggregate Concrete

    Institute of Scientific and Technical Information of China (English)

    WANG Zhi; SHI Caijun; SONG Jianming

    2009-01-01

    The effects of glass powder on the strength development, chloride permeability and potential alkali-aggregate reaction expansion of lightweight aggregate concrete were investigated.Ground blast furnace slag, coal fly ash and silica fume were used as reference materials. The re-placement of cement with 25% glass powder slightly decreases the strengthes at 7 and 28 d, but shows no effect on 90 d's. Silica fume is very effective in improving both the strength and chloride penetra-tion resistance, while ground glass powder is much more effective than blast furnace slag and fly ash in improving chloride penetration resistance of the concrete. When expanded shale or clay is used as coarse aggregate, the concrete containing glass powder does not exhibit deleterious expansion even if alkali-reactive sand is used as fine aggregate of the concrete.

  14. Determination of the extractive capacity of para-tert butyl calix[8]arene octa-phosphinoylated towards uranyl ions from an aqueous-acidic-salty medium; Determinacion de la capacidad extractiva del p-ter-butilocalix[8]areno octa-fosfinoilado hacia iones uranilo de un medio acuo-acido salino

    Energy Technology Data Exchange (ETDEWEB)

    Serrano V, E. C.

    2011-07-01

    The extraction properties of octa-phosphinoylated para-tert butyl calix[8]arene (prepared in the laboratory) in chloroform towards uranyl ions from an aqueous-acidic-salty medium (HNO{sub 3}-3.5 NaNO{sub 3}) containing uranyl nitrate salt, was investigated. Two spectroscopic techniques UV/Vis and Luminescence were used for this study. The latter permitted analyze the fluorescence from the uranyl ions influenced by the surrounding medium. Both permitted to learn about the power of this calixarene as extractant towards the mentioned ions. Its extraction ability or capability using this calixarene at 5.91 x 10{sup -4} M towards the uranyl ions was 400% as determined by UV/Vis while fluorescence revealed 100% of uranyl ion extraction. A closed analysis of the results obtained by using these techniques revealed that the stoichiometry of the main extracted species was 1calixarene:2 uranyl ions. The loading capacity of the calixarene ligand towards the uranyl ions was also investigated using both techniques. UV/Vis resulted to be inadequate for quantifying exactly the loading capacity of the calixarene whereas luminescence was excellent indeed, using a 5.91 x 10{sup -4} M calixarene concentration, its loading capacity was 0.157 M of free uranyl ions from 0.161 M of uranyl ions present in the aqueous-acidic-salty medium. The extracts from the ability and capacity studies were concentrated to dryness, purified and the dried extracts were analyzed by infrared and neutron activation analysis. By these techniques it was demonstrated that during the extraction of the uranyl ions by the calixarene ligand they form thermodynamically and kinetically stable complexes, since in the solid state, the 1:2, calixarene; uranyl ions stoichiometry was kept with the minimum formula: (UO{sub 2}){sub 2}B{sub 8}bL{sup 8}(NO{sub 3}){sub 4}(H{sub 2}O){sub 4}CHCl{sub 3}(CH{sub 3}OH){sub 3} the methanol molecules come from its purification. It is proposed that B{sub 8}bL{sup 8} calixarene in

  15. Adsorption of Rh(III) complexes from chloride solutions obtained by leaching chlorinated spent automotive catalysts on ion-exchange resin Diaion WA21J

    International Nuclear Information System (INIS)

    It was found that Rh, Pd and Pt contained in the spent ceramic automotive catalysts could be effectively extracted by dry chlorination with chlorine. In order to concentrate Rh(III) ions contained in the chloride solutions obtained, thermodynamic and kinetics studies for adsorption of Rh(III) complexes from the chloride solutions on an anionic exchange resin Diaion WA21J were carried out. Rh, Pd, Pt, Al, Fe, Si, Zn and Pb from the chloride solution could be adsorbed on the resin. The distribution coefficients (Kd) of Rh(III) decreased with the increase in initial Rh(III) concentration or in adsorption temperature. The isothermal adsorption of Rh(III) was found to fit Langmuir, Freundlich and Dubinin-Kaganer-Radushkevich models under the adsorption conditions. The maximum monolayer adsorption capacities Qmax based on Langmuir adsorption isotherms were 6.39, 6.61 and 5.81 mg/g for temperatures 18, 28 and 40 deg. C, respectively. The apparent adsorption energy of Rh was about -7.6 kJ/mol and thus Rh(III) adsorption was a physical type. The experimental data obtained could be better simulated by pseudo-first-order kinetic model and the activation energy obtained was 6.54 J/mol. The adsorption rate of Rh(III) was controlled by intraparticle diffusion in most of time of adsorption process.

  16. Progress of Carbonation in Chloride Contaminated Concretes

    OpenAIRE

    Wang, Yaocheng; Basheer, P.A.M.; Nanukuttan, S; Bai, Y.

    2016-01-01

    Concretes used in marine environment are generally under the cyclic effect of CO2 and chloride ions (Cl-). To date, the influence of carbonation on ingress of chloride ions in concretes has been widely studied; in comparison, study on the influence of Cl- on the progress of carbonation is limited. During the study, concretes were exposed to independent and combined mechanisms of carbonation and chloride ingress regimes. Profiles of apparent pH and chloride concentration were used to indicate ...

  17. 有机肥料中氯离子检测方法的研究%Study on detection method of chloride ion in organic fertilizers

    Institute of Scientific and Technical Information of China (English)

    杜颖; 刘善江; 陈益山

    2015-01-01

    通过全自动电位滴定法与佛尔哈德法对有机肥料样品中氯离子含量进行测定比较,结果显示,自动电位滴定法不受溶液颜色干扰,测定更为快速、准确,平均回收率为97.1%。此种方法缩短了前处理时间,使实验操作更为便捷。同时该法适用于植株中的氯离子含量的测定。%The chloride ion content in organic fertilizer samples were determined using both automatic potentiometric titration and Volhard method and they were compared in this study. The results showed that the automatic potentiometric titration was not influenced by solution color it was more rapidly and accurately than Volhard method, and the average recovery rate was 97. 1%. This method could shorten the pretreatment time, make the operation more convenient. By the way, this method could be suitable for the determination of chloride ion content in plants.

  18. Automatic Potentiometric Titrator Determinated Chloride Ions in Water%自动电位滴定仪测定水中氯离子的探讨

    Institute of Scientific and Technical Information of China (English)

    李芳; 李文胜

    2014-01-01

    Using automatic potentiometric titrator, standard solution of silver nitrate was calibrated and chloride ions in industrial circulating wate was determined. The matters need attention of the electrode maintenance and the end point of titration to set were summarized. The result showed that the determination of chloride ions in water by using the instrument, its accuracy and precision can be obtained satisfactory results.%通过使用自动电位滴定仪标定硝酸银标准溶液和测定工业循环水中氯离子的实验研究,总结了在使用中应注意的电极的维护保养和滴定终点设定方面的一些规律,结果表明用该仪器测定水中氯离子,其准确性和精密度均可获得满意的结果。

  19. Investigation of ion-catalyzed telomerization. XXIV. The composition of sesquiterpene chlorides - the diadducts of isoprene with its monohydrochlorides

    International Nuclear Information System (INIS)

    The isomeric composition of primary allylic sesquiterpene chlorides, i.e., the diadducts of the isoprene telomer with its monohydrochlorides, was interpreted by 13C NMR spectroscopy. The diadducts are formed predominantly by telomerization chain growth, and the chemical structure and composition are determined by the chemical structure of the taxogen. The possibility of increasing the yield with increase in the excess of the taxogen is suggested

  20. Ion pairing with bile salts modulates intestinal permeability and contributes to food-drug interaction of BCS class III compound trospium chloride.

    Science.gov (United States)

    Heinen, Christian A; Reuss, Stefan; Amidon, Gordon L; Langguth, Peter

    2013-11-01

    In the current study the involvement of ion pair formation between bile salts and trospium chloride (TC), a positively charged Biopharmaceutical Classification System (BCS) class III substance, showing a decrease in bioavailability upon coadministration with food (negative food effect) was investigated. Isothermal titration calorimetry provided evidence of a reaction between TC and bile acids. An effect of ion pair formation on the apparent partition coefficient (APC) was examined using (3)H-trospium. The addition of bovine bile and bile extract porcine led to a significant increase of the APC. In vitro permeability studies of trospium were performed across Caco-2-monolayers and excised segments of rat jejunum in a modified Ussing chamber. The addition of bile acids led to an increase of trospium permeation across Caco-2-monolayers and rat excised segments by approximately a factor of 1.5. The addition of glycochenodeoxycholate (GCDC) was less effective than taurodeoxycholate (TDOC). In the presence of an olive oil emulsion, a complete extinction of the permeation increasing effects of bile salts was observed. Thus, although there are more bile acids in the intestine in the fed state compared to the fasted state, these are not able to form ion pairs with trospium in fed state, because they are involved in the emulsification of dietary fats. In conclusion, the formation of ion pairs between trospium and bile acids can partially explain its negative food effect. Our results are presumably transferable to other organic cations showing a negative food effect. PMID:23750707

  1. 地下水中SO42-和Cl-对Fe0降解TCE的效应研究%Effect of Sulfate and Chloride Ion in Groundwater on TCE Degradation by ZVI-PRB

    Institute of Scientific and Technical Information of China (English)

    张晓庆; 朱雪强; 卜丹阳; 许映军; 陈强

    2011-01-01

    文章基于渗透反应墙技术,通过实验室柱实验分析不同浓度的SO42-和Cl-单独作用下Fe0降解TCE的效果.结果表明:在相同Fe0条件下,随SO42-浓度增大,出水口TCE去除率提高,且SO42-在TCE降解反应中由抑制作用逐渐转换为促进作用;此外随Cl-浓度增大,出水口TCE去除率呈下降趋势,且Cl-在TCE降解反应中由促进作用逐渐转变为抑制作用;同时研究结果表明,Fe0反应柱对Cl-具有一定吸附作用.%Column experiments were done to determine effects of sulfate and chloride ion on TCE degradation by ZVI-PRB. Results showed that sulfate and chloride ion had a dual effect on TCE degradation in the system of ZVI-PRB. As sulfate concentration increased, the efficiency of TCE degradation got better. Sulfate could inhibit the reaction when its concentration was low, however, when its concentration increased, sulfate had a promoting action to the reaction. As chloride ion concentration increased, the efficiency of TCE degradation became worse. When there was a low concentration, chloride ion had a promoting action to the reaction, and when its concentration increased, chloride ion could inhibit the reaction. The study showed that the experiment column can adsorb chloride ion.

  2. Design of a Remote Monitoring System for Evaluation of Corrosión in Reinforced Concrete Structures under Chloride Ion Attack

    Directory of Open Access Journals (Sweden)

    Roa-Rodríguez Guillermo

    2015-09-01

    Full Text Available In this paper it was designed and built a remote monitoring equipment that allows to obtain the corrosion potential in reinforcing steels embedded in reinforced concrete, which were previously subjected to chloride attack in a hostile environment. The monitoring system, based on ASTM standard C876-91, determines from 0% to 100% the probability of corrosion on the samples tested. The system provides ease of perform field installation, if there is cellular network coverage, and may be operated remotely using text messages to start and stop measurements, whose results are stored in a local data logger on microSD cards and then are sent via the general packet radio service (GPRS to a web server which allows to access to the data via a web page, where the test results can be seen graphically. The concrete samples used as reference for monitoring degradation were immersed in chloride ion (3.5% NaCl for 12 months. Data for corrosion potential were generated through the exposureconcrete interface, corresponding to a system with a 90% probability of corrosion.

  3. Smart carbon nanotube/fiber and PVA fiber-reinforced composites for stress sensing and chloride ion detection

    Science.gov (United States)

    Hoheneder, Joshua

    Fiber reinforced composites (FRC) with polyvinyl alcohol (PVA) fibers and carbon nanofibers (CNF) had an excellent flexural strength in excess of 18.5 MPa compared to reference samples of 15.8 MPa. It was found that the developed, depending on applied stress and exposure to chloride solutions, composites exhibit some electrical conductivity, from 4.20×10 -4 (Ω-1m-1 to 4.13×10 -4 Ω-1m-1. These dependences can be characterized by piezioresistive and chemoresistive coefficients demonstrating that the material possesses self-sensing capabilities. The sensitivity to stain and chloride solutions can be enhanced by incorporating small amounts of carbon nanofibers (CNF) or carbon nanotube (CNT) into composite structure. Conducted research has demonstrated a strong dependency of electrical properties of composite on crack formation in moist environments. The developed procedure is scalable for industrial application in concrete structures that require nondestructive stress monitoring, integrity under high service loads and stability in harsh environments.

  4. Formation of La3+, Pr3+, Eu3+, Er3+, and Lu3+ complexes with chloride ions, in aqueous medium

    International Nuclear Information System (INIS)

    The constants of stability of the complexes of La3+, Pr3+, Eu3+, Er3+, and Lu3+ with Cl- ions, its were determined, in the aqueous medium of HCI - HClO4 and by a solvent extraction method. The dinonyl naphtalene sulfonic acid in n-heptane was used as extractant. The lanthanides concentration, it was measured by a VIS spectrophotometry method and by another radiochemical. The ions specific interaction theory (SIT) it was used for the extrapolation to ionic force 0 M. The results indicate that the stability constants of the LnCI2+ species diminishes when increasing the ion force and the charge density. (Author)

  5. Accelerated solvent extraction followed by on-line solid-phase extraction coupled to ion trap LC/MS/MS for analysis of benzalkonium chlorides in sediment samples

    Science.gov (United States)

    Ferrer, I.; Furlong, E.T.

    2002-01-01

    Benzalkonium chlorides (BACs) were successfully extracted from sediment samples using a new methodology based on accelerated solvent extraction (ASE) followed by an on-line cleanup step. The BACs were detected by liquid chromatography/ion trap mass spectrometry (LC/MS) or tandem mass spectrometry (MS/MS) using an electrospray interface operated in the positive ion mode. This methodology combines the high efficiency of extraction provided by a pressurized fluid and the high sensitivity offered by the ion trap MS/MS. The effects of solvent type and ASE operational variables, such as temperature and pressure, were evaluated. After optimization, a mixture of acetonitrile/water (6:4 or 7:3) was found to be most efficient for extracting BACs from the sediment samples. Extraction recoveries ranged from 95 to 105% for C12 and C14 homologues, respectively. Total method recoveries from fortified sediment samples, using a cleanup step followed by ASE, were 85% for C12BAC and 79% for C14-BAC. The methodology developed in this work provides detection limits in the subnanogram per gram range. Concentrations of BAC homologues ranged from 22 to 206 ??g/kg in sediment samples from different river sites downstream from wastewater treatment plants. The high affinity of BACs for soil suggests that BACs preferentially concentrate in sediment rather than in water.

  6. Adsorption behavior of poly(dimethyl-diallylammonium chloride) on pulp fiber studied by cryo-time-of-flight secondary ion mass spectrometry and cryo-scanning electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Masumi, Takashi [Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho Chikusa-ku, Nagoya, Aichi 464-8601 (Japan); Matsushita, Yasuyuki, E-mail: ysmatsu@agr.nagoya-u.ac.jp [Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho Chikusa-ku, Nagoya, Aichi 464-8601 (Japan); Aoki, Dan [Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho Chikusa-ku, Nagoya, Aichi 464-8601 (Japan); Takama, Ruka [Technical Center, Nagoya University, Furo-cho Chikusa-ku Nagoya, Aichi 464-8601 (Japan); Saito, Kaori [Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho Chikusa-ku, Nagoya, Aichi 464-8601 (Japan); Kuroda, Katsushi [Department of Wood Properties, Forestry and Forest Products Research Institute, 1 Matsunosato, Tsukuba, Ibaraki 305-8687 (Japan); Fukushima, Kazuhiko [Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho Chikusa-ku, Nagoya, Aichi 464-8601 (Japan)

    2014-01-15

    In this study, the adsorption behavior of poly(dimethyl-diallylammonium chloride) (PDADMAC), a retention agent used in papermaking, in a dual polymer system with anionic poly(acrylamide) (A-PAM) was investigated by time-of-flight secondary ion mass spectrometry (TOF-SIMS). Initially, fragment structures and cleavage patterns were identified via TOF-SIMS experiments with deuterium-labeled PDADMAC and the unlabeled analogue. Visualization of PDADMAC on a dry handsheet surface using traditional TOF-SIMS analysis indicated that the electrostatic interaction between coagulated PDADMAC and A-PAM was relatively weak. A novel cryo-TOF-SIMS/SEM system enabled the evaluation of a wet handsheet containing PDADMAC. Analysis of this sample indicated that PDADMAC adsorbs onto the fiber surface and collects preferentially on the tangled fibrils located between fibers.

  7. Adsorption behavior of poly(dimethyl-diallylammonium chloride) on pulp fiber studied by cryo-time-of-flight secondary ion mass spectrometry and cryo-scanning electron microscopy

    International Nuclear Information System (INIS)

    In this study, the adsorption behavior of poly(dimethyl-diallylammonium chloride) (PDADMAC), a retention agent used in papermaking, in a dual polymer system with anionic poly(acrylamide) (A-PAM) was investigated by time-of-flight secondary ion mass spectrometry (TOF-SIMS). Initially, fragment structures and cleavage patterns were identified via TOF-SIMS experiments with deuterium-labeled PDADMAC and the unlabeled analogue. Visualization of PDADMAC on a dry handsheet surface using traditional TOF-SIMS analysis indicated that the electrostatic interaction between coagulated PDADMAC and A-PAM was relatively weak. A novel cryo-TOF-SIMS/SEM system enabled the evaluation of a wet handsheet containing PDADMAC. Analysis of this sample indicated that PDADMAC adsorbs onto the fiber surface and collects preferentially on the tangled fibrils located between fibers.

  8. Adsorption behavior of poly(dimethyl-diallylammonium chloride) on pulp fiber studied by cryo-time-of-flight secondary ion mass spectrometry and cryo-scanning electron microscopy

    Science.gov (United States)

    Masumi, Takashi; Matsushita, Yasuyuki; Aoki, Dan; Takama, Ruka; Saito, Kaori; Kuroda, Katsushi; Fukushima, Kazuhiko

    2014-01-01

    In this study, the adsorption behavior of poly(dimethyl-diallylammonium chloride) (PDADMAC), a retention agent used in papermaking, in a dual polymer system with anionic poly(acrylamide) (A-PAM) was investigated by time-of-flight secondary ion mass spectrometry (TOF-SIMS). Initially, fragment structures and cleavage patterns were identified via TOF-SIMS experiments with deuterium-labeled PDADMAC and the unlabeled analogue. Visualization of PDADMAC on a dry handsheet surface using traditional TOF-SIMS analysis indicated that the electrostatic interaction between coagulated PDADMAC and A-PAM was relatively weak. A novel cryo-TOF-SIMS/SEM system enabled the evaluation of a wet handsheet containing PDADMAC. Analysis of this sample indicated that PDADMAC adsorbs onto the fiber surface and collects preferentially on the tangled fibrils located between fibers.

  9. Perméabilité au gaz et aux ions chlore des mortiers à base de laitier de faible hydraulicité Gas and chloride ions permeability of mortar with low hydraulicity slag

    Directory of Open Access Journals (Sweden)

    Courard L.

    2012-09-01

    Full Text Available La durabilité des bétons au laitier de haut fourneau dépend fortement de l’activité hydraulique du laitier. Dans cette étude, un laitier algérien, caractérisé par une faible hydraulicité, est utilisé dans la fabrication de mortiers comme substituant du ciment à des taux de 0, 30 et 50%. En plus d’une caractérisation mécanique, l’effet du laitier sur la durabilité des mortiers est évalué par des essais de perméabilité à l’oxygène, de diffusion de chlorures en régime permanent ainsi que de conduction des ions chlore (essai accéléré ASTM. Les résultats montrent, malgré une faible réactivité du laitier, une amélioration de la perméabilité à l’oxygène à long terme (360 jours pour les mortiers au laitier, particulièrement pour un taux de 50%. La présence du laitier réduit la perméabilité aux ions chlore, d’une part, en augmentant le temps de passage des chlorures à travers le mortier et, d’autre part, en diminuant le taux de diffusion. Par ailleurs, une faible conduction des chlorures est observée pour les mortiers au laitier, montrant une similitude avec les résultats d’essai de diffusion en régime permanent. Durability of ground granulated blast furnace slag concrete depends largely on the hydraulic activity of the slag. In this study, a low activity Algerian slag is used as a substitution to cement in the manufacture of mortars at rates of 0, 30 and 50%. In addition to the mechanical characterization, the effect of slag on the durability of mortars is evaluated by oxygen permeability test, chlorides diffusion test in steady state and chlorides conduction test (ASTM accelerated test. Despite the low activity of slag, the results show improved oxygen permeability at long term (360 days for slag mortars, particularly for a 50% rate. The presence of slag reduces the chloride permeability by on one hand increasing the time of passage of the chlorides through mortar and, on the other hand, by

  10. Modified potentiometric poly(vinyl chloride)nonactin membrane electrode: an improved transducer for the selective detection of ammonium ions

    International Nuclear Information System (INIS)

    Ion selective electrode technique is an effective analytical approach for detecting or assaying various ions of interest. Broadly it can be classified into glass, liquid and polymer type membrane electrodes. Among these, polymer based membrane sensors are relatively easy to manufacture and can be designed as per requirement, particularly regarding miniaturization. The main source of ammonium ions in environment is the biodegradation of bio waste and chemical industry. Detection of ammonium ions is of primary importance regarding the biological activity of water reservoirs/marine life. The available photometric techniques can monitor ammonium ions effectively, however, disadvantages like sample processing and chances of contamination exist. In the present study a potentiometric ammonium ions transducer based on PVC-non actin membrane has been developed and optimized. Its effective use in the development of bio sensors has been proposed. These types of bio sensors are fabricated by immobilizing appropriate enzyme for a particular bio product. The end product of the catalysis is sensed by the transducer. (author)

  11. 环境条件和应力水平对混凝土中氯离子传输的影响%Effects of environmental conditions and stress level on chloride ion transport in concrete

    Institute of Scientific and Technical Information of China (English)

    张伟平; 张庆章; 顾祥林; 钟丽娟; 黄庆华

    2013-01-01

    To investigate the diffusion process of chloride ion in concrete under atmosphere environment, a series of tests were conducted under the conditions of different salt-fog spray angle, environment temperature, mass concentration of sodium chloride solution and compressive stress level. The results show that surface chloride ion mass fraction for specimens under different spray angles of salt-fog were different, which leads to a great change of diffusion degree of chloride ions in concrete. The surface chloride ion mass fraction is high when the angle of erosion surface is 0° or 45°, which causes severe erosion in concrete. The surface chloride ion mass fraction is increased with the increasing of mass concentration of sodium chloride solution until a stable value. The apparent diffusion coefficient of chloride ion is increased with the increasing of temperature, and decreased significantly with the increasing of compressive stress level due to the dense concrete by stress.%为了研究自然环境中混凝土的氯盐侵蚀过程,进行了不同侵蚀角度、氯化钠溶液质量浓度、环境温度、应力水平下的混凝土盐雾加速侵蚀试验,分别探讨了在不同的条件下氯离子在混凝土中的扩散规律.结果表明:盐雾箱中试件放置角度不同,其表面氯离子聚集量会不同,最终导致氯离子侵蚀程度不同,其中以平面或45°侧面为侵蚀面时,表面氯离子质量分数较高,氯离子侵蚀程度严重;随着氯化钠溶液质量浓度的增大,盐雾沉降量增加,表面氯离子质量分数也增加,不过最终会达到一个衡定值;随着环境温度的升高,氯离子表观扩散系数逐渐增大;由于压应力状态下混凝土内部结构更加密实,氯离子表现扩散系数显著减小.

  12. Influence of heat treatment on microstructure and passivity of Cu–30Zn–1Sn alloy in buffer solution containing chloride ions

    Indian Academy of Sciences (India)

    U Tabrizi; R Parvizi; A Davoodi; M H Moayed

    2012-02-01

    Tin as an alloying element is of great interest in brasses for dezincification impediment. In this paper, Cu–30Zn–1Sn alloy was submitted to three different heat treatments, viz. A (heating up to 800 °C for 20 h, held at 200 °C for 20 h in salt bath and air cooled), B (heating up to 800 °C for 20 h and water quenched) and C (heating up to 600 °C for 20 h and water quenched). The influence of heat treatment on microstructure was evaluated by OM and SEM–EDS analysis. The corrosion resistance in buffer solution (pH 9), H3BO3/Na2B4O7.10H2O, with various concentrations of chloride ions was evaluated by potentiodynamic polarization curves and compared with multicomponent Pourbaix diagrams. A correlation between the heat treatment, microstructure and passivity of the heat treated samples was observed. The results indicated that all heat treatment procedures led to formation of , and -Sn-rich phases as microstructure constituents with a small fraction of ' phase in A. Sn-rich phase appears in grain boundaries and its morphology was slightly changed due to heat treatment. Beneficial influence of low concentration chloride ions on passivity was associated with the formation of copper oxides/hydroxide and chloride complexes. Deterioration was observed at concentrations higher than 0.05 M NaCl due to accelerated dissolution of copper by formation of CuCl$^{−}_{2}$. As a result of dezincification process, preferential corrosion attack and copper redeposition on phase (matrix) were observed. However, Sn-rich (1) phase in grain boundaries was not attacked due to SnO2 formation. In buffer solution, the higher passivity current density in A was related to the presence of small amount of ' phase. On the other hand, in 1 M NaCl, lower critical current density for passivation in B and A (about two times lower than C) was attributed to the grain size effect.

  13. A conductivity study of unsymmetrical 2:1 type "complex ion" electrolyte: cadmium chloride in dilute aqueous solutions.

    Science.gov (United States)

    Apelblat, Alexander; Esteso, Miguel A; Bešter-Rogač, Marija

    2013-05-01

    Systematic and precise measurements of electrical conductivities of aqueous solutions of cadmium chloride were performed in the 2 × 10(-5)-1 × 10(-2) mol·dm(-3) concentration range, from 278.15 to 313.15 K. Determined conductances were interpreted in terms of molecular model which includes a mixture of two 1:1 and 2:1 electrolytes. The molar limiting conductances of λ(0)(CdCl(+), T) and λ(0)(1/2Cd(2+), T), the equilibrium constants of CdCl(+) formation K(T) and the corresponding standard thermodynamic functions were evaluated using the Quint-Viallard conductivity equations, the Debye-Hückel equations for activity coefficients and the mass-action equation. An excellent agreement between calculated and experimental conductivities was reached. PMID:23534843

  14. Zirconium ion selective electrode based on bis(diphenylphosphino) ferrocene incorporated in a poly(vinyl chloride) matrix

    Energy Technology Data Exchange (ETDEWEB)

    Gholivand, M.B. [Department of Chemistry, Razi University, Kermanshah (Iran, Islamic Republic of)]. E-mail: mbgholivand@yahoo.com; Babakhanian, A. [Department of Chemistry, Razi University, Kermanshah (Iran, Islamic Republic of); Joshaghani, M. [Department of Chemistry, Razi University, Kermanshah (Iran, Islamic Republic of)

    2007-02-19

    A novel potentiometric zirconium - PVC matrix membrane sensor incorporating bis(diphenylphosphino) ferrocene as an electroactive material and tris(2-ethylhexyl)phosphate as solvent mediator is described. In mixed acetate buffer solution of pH 4.8, the sensor displays a rapid and linear response for zirconium ion over the concentration range 1.0 x 10{sup -1} to 1.0 x 10{sup -7} mol L{sup -1} with a good slope of 59.7 {+-} 0.3 mV per decade and detection limit 1.8 x 10{sup -8} mol L{sup -1}. The best performance was obtained with membrane composition 33% PVC, 65% TEHP, 1% NaTPB and 1% ionophore. The proposed electrode revealed excellent selectivity for zirconium ion over a wide variety of alkali, alkaline earth, transition and heavy metal ions and could be used in a pH range of 4.15-7.8. The electrode was applied for at least 1 month without any considerable divergence in the potential responses. The practical utility of the electrode has been demonstrated by its use as an indicator electrode in the potentiometric titration of zirconium ions with sodium fluoride and in determination of zirconium ion in some alloy, tape and waste water samples.

  15. Chloride in vesicular trafficking and function.

    Science.gov (United States)

    Stauber, Tobias; Jentsch, Thomas J

    2013-01-01

    Luminal acidification is of pivotal importance for the physiology of the secretory and endocytic pathways and its diverse trafficking events. Acidification by the proton-pumping V-ATPase requires charge compensation by counterion currents that are commonly attributed to chloride. The molecular identification of intracellular chloride transporters and the improvement of methodologies for measuring intraorganellar pH and chloride have facilitated the investigation of the physiology of vesicular chloride transport. New data question the requirement of chloride for pH regulation of various organelles and furthermore ascribe functions to chloride that are beyond merely electrically shunting the proton pump. This review surveys the currently established and proposed intracellular chloride transporters and gives an overview of membrane-trafficking steps that are affected by the perturbation of chloride transport. Finally, potential mechanisms of membrane-trafficking modulation by chloride are discussed and put into the context of organellar ion homeostasis in general. PMID:23092411

  16. The Cystic Fibrosis Transmembrane Conductance Regulator and Chloride-Dependent Ion Fluxes of Ovine Vocal Fold Epithelium

    Science.gov (United States)

    Leydon, Ciara; Fisher, Kimberly V.; Lodewyck-Falciglia, Danielle

    2009-01-01

    Purpose: Ion-driven transepithelial water fluxes participate in maintaining superficial vocal fold hydration, which is necessary for normal voice production. The authors hypothesized that Cl[superscript -] channels are present in vocal fold epithelial cells and that transepithelial Cl[superscript -] fluxes can be manipulated pharmacologically.…

  17. Naked eye sensor on polyvinyl chloride platform of chromo-ionophore molecular assemblies: A smart way for the colorimetric sensing of toxic metal ions

    International Nuclear Information System (INIS)

    We demonstrate the possibility of fabricating a simple, naked eye colorimetric sensor miniature, using chromo-ionophore molecular assemblies anchored on polyvinyl chloride (PVC) surface. The ion-sensing probe (4-n-dodecyl-6-(2-thiazolylazo)-resorcinol) provides a better efficiency with PVC platform in developing a series of colour transitions, while targeting trace levels of Cd2+, Pb2+ and Hg2+. The physical properties of the film sensor are controlled by measuring the probe isotherm plot. The surface morphology and molecular composition of the solid-state optical sensor are characterized using X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The changes in sensor's optical intensity and its response time for the target analytes are followed by absorption spectroscopy. High speed of response (t ≤ 5 min) and confidence in determination of analytes from chemically complex matrices has been achieved, using simulated synthetic mixtures and spiked real environmental samples, with a relative standard deviation of 2+, Pb2+ and Hg2+ ions, respectively. The sensor strips are reversible and reusable without any change in the sensing efficiency, up to four cycles. The signal response observed with the proposed method is consistent between sensors, and also are stable over time

  18. Photoelectrocatalytic decontamination of oilfield produced wastewater containing refractory organic pollutants in the presence of high concentration of chloride ions

    International Nuclear Information System (INIS)

    The feasibility study of the application of the photoelectrocatalytic decontamination of high saline produced water containing refractory organic pollutants was investigated in the slurry photoelectrocatalytic reactor with nanometer TiO2 particle prepared with sol-gel method using the acetic acid as hydrolytic catalyst. The efficiency of the photoelectrocatalytic decontamination of produced water was determined with both COD removal from the tested wastewater and the decrease of mutagenic activity evaluated by Ames tests. The experimental results showed that the photoelectrocatalysis is a quite efficient process for decontaminating the produced water, although there are high concentration of salt existed in oilfield wastewater. We found that the COD removal efficiencies by photoelectrocatalytic process are much higher than that of by photocatalytic or electrochemical oxidation individually in the photoelectrocatalytic reactor. The COD removal can be substantially improved by the added H2O2 and the generation of active chlorine from high concentration chlorides in the wastewater. The effects of various operating conditions, such as initial COD concentration, applied cell voltage, catalyst amount and initial pH value of solution, on the photoelectrocatalytic efficiencies, is also investigated in detail. The results showed that when the raw produced wastewater was diluted in a 1:1 (v/v) ratio, there is a highest COD removal efficiency. And the photoelectrocatalytic degradation of organic pollutants in saline water is much favored in acidic solution than that in neutral and/or alkaline solution

  19. Comment on ''Mean force potential for the calcium--chloride ion pair in water'' [J. Chem. Phys. 99, 4229 (1993)

    International Nuclear Information System (INIS)

    The interionic potential of mean force (pmf) for the Ca++--Cl- ion pair in water is computed using the molecular dynamics computer simulation technique. The calculated pmf indicates a stable contact pair (CIP) and a solvent-separated pair (SSIP) centered at 2.9 and 5.0 A with a 2.8 kcal/mol barrier to dissociation. The SSIP well is about 2.0 kcal/mol deeper than the CIP suggesting that water molecules in the first hydration shell are strongly coordinated to the Ca++ ion. Our results do not agree with the pmf reported recently by Guardia, Robinson, Padro [J. Chem. Phys. 99, 4229 (1993)]. Possible reasons for the discrepancy are discussed

  20. Analysis of sugars and sugar polyols in atmospheric aerosols by chloride attachment in liquid chromatography/negative ion electrospray mass spectrometry.

    Science.gov (United States)

    Wan, Eric C H; Yu, Jian Zhen

    2007-04-01

    Sugars and sugar polyols are relatively abundant groups of water-soluble constituents in atmospheric aerosols. This paper describes a method that uses liquid chromatography-mass spectrometry (LC-MS) to analyze sugars and sugar polyols in atmospheric aerosols, ranging from C3 sugar alcohols to trisaccharides. Postcolumn addition of chloroform in acetonitrile was found to greatly enhance ionization of these compounds by forming chloride adduct ions in the negative-ion mode using electrospray ionization. A gradient elution program starting at 5%:95% H20/acetonitrile and ending at 30%:70% H2O/acetonitrile provides baseline separations of the sugars and sugar polyols on an amino-based carbohydrate column. The detection limits based on quantification of [M + 35Cl]- adduct ions were in the order of 0.1 microM. By eliminating the need for derivatization, this LC-MS based method provides a simpler alternative method to the commonly used and more laborious gas-chromatography based methods. It also has an additional advantage of being able to quantify trisaccharide sugars. The method was applied to analyze 30 ambient samples of fine particulate matter collected at a site away from urban centers in Hong Kong. The sugar compounds positively identified and detected in the ambient samples included four sugar alcohols (glycerol, erythritol, xylitol, and mannitol), three monosacchride sugars (xylose, fructose, and glucose), two disaccharides (sucrose, trehalose), two trisaccharides (melezitose, raffinose), and one anhydrosugar (levoglucosan). The sum of these sugar and sugar polyol compounds ranged from 38 to 1316 ng m(-3), accounting for an average of 1.3% organic carbon mass. Through the use of a principal component analysis of the ambient measurements, the mono- to trisactharide sugars and C3-C5 sugar polyols were identified to be mainly associated with soil/soil microbiota while the anhydrosugar (levoglucosan) was associated with biomass burning. PMID:17438800

  1. Simultaneous determination of trace amounts of borate, chloride and fluoride in nuclear fuels employing ion chromatography (IC) after their extraction by pyrohydrolysis.

    Science.gov (United States)

    Jeyakumar, S; Raut, Vaibhavi V; Ramakumar, K L

    2008-09-15

    An accurate and sensitive method based on the combination of pyrohydrolysis-ion chromatography (PH-IC) is proposed for the simultaneous separation and determination of boron as borate, chloride and fluoride in nuclear fuels such as U(3)O(8), (Pu,U)C and Pu-alloys. The determination is based on the initial pyrohydrolytic extraction of B, Cl and F from the samples as boric acid, HCl and HF, respectively, which are subsequently separated by ion chromatography (IC). The proposed method significantly improves the existing analytical methodology as it combines the determination of boron, a critical trace constituent in nuclear materials, along with F(-) and Cl(-) for chemical quality control measurements. Various experimental parameters were optimized to achieve maximum recoveries of the analytes during the pyrohydrolysis and to get better ion chromatographic (IC) separation of borate, F(-) and Cl(-) along with other anions such as CH(3)COO(-), NO(2)(-), NO(3)(-), Br(-), PO(4)(3-) and SO(4)(2-). Recoveries of more than 93% could be obtained for all the analytes in the sample (0.5-1.5 g) at 1200+/-25K and distilled with pre-heated steam at the flow rate of 0.3 mL/min. An isocratic elution with a mobile phase of 0.56 M d-mannitol in 6.5mM NaHCO(3) was used for the IC separation. The detection limits for B (as borate), F(-) and Cl(-) were 24, 13 and 25 microgL(-1), respectively. Precision of about 5% was achieved for determination of boron, Cl(-) and F(-) in the samples containing 1-5 ppm(w) of boron, and 10-25 ppm(w) of Cl and F. The method was validated with reference materials and successfully applied to the nuclear fuels. The methodology is easy to adapt on routine basis. PMID:18761185

  2. Durability of API class B cement pastes exposed to aqueous solutions containing chloride, sulphate and magnesium ions

    Directory of Open Access Journals (Sweden)

    Hernández, M. E.

    2008-12-01

    Full Text Available This paper discusses a durability study conducted on API class B cement, the type used in shallow oil wells, when exposed to aggressive formation water. Its resistance to the major ions, namely –SO4=, Mg+2 and Cl-–, is related both to its capacity to assimilate the aggressive action of each harmful agent and to the changes in the chemical reactivity of some of its components. The methodology used consisted in preparing and immersing cement specimens in neutral solutions containing variable concentrations of these ions to monitor the chemical reactions taking place. These solutions were analyzed and XRD studies were conducted for over a year to identify mineralogical variations. The purposes of the study were to determine the effects of joint ionic attack on this kind of cement and to monitor the variations in the calcium concentration in the aqueous solutions of Na2SO4, MgCl2 and NaCl in contact with API class B cement pastesEste trabajo se basa en el estudio de la durabilidad de un cemento API clase B, utilizado en pozos petrolíferos someros, frente a la agresividad de las aguas de formación a las que puede estar expuesto. Su eficacia frente a la exposición a los iones más importantes –SO4=, Mg+2 y Cl-– se relaciona con su capacidad de asimilar la acción agresiva de cada agente perjudicial, así como de las reacciones químicas que sufra por la reactividad de alguno de sus compuestos. La metodología aplicada supone la preparación de probetas de este cemento y su inmersión en disoluciones neutras, conteniendo los referidos iones a distintas concentraciones, para evaluar el desarrollo de las reacciones existentes en su seno. A tal fin se realizaron análisis de las disoluciones y estudios de DRX durante más de un año para conocer su evolución mineralógica. El objetivo del trabajo ha sido determinar los efectos resultantes de los ataques conjuntos de los citados iones al referido cemento; así como la observación de las

  3. Formation of an Ion-Pair Molecule with a Single NH+...Cl- Hydrogen Bond: Raman spectra of 1,1,3,3-Tetramethylguanidinium chloride in the solid state, in solution and in the vapor phase

    DEFF Research Database (Denmark)

    Berg, Rolf W.; Riisager, Anders; Fehrmann, Rasmus

    2008-01-01

    Some ionic compounds (salts) form liquids when heated to temperatures in the range of 200-300 °C. They may be referred to as moderate temperature ionic liquids. An example of such a compound is the 1,1,3,3- tetramethylguanidinium chloride, [TMGH]Cl, melting at ∼212 °C. The chemistry of this...... dimeric chloride ion-pair salt converged to give geometries near the established crystal structure of [TMGH]Cl. The structures and their binding energies are given as well as calculated vibrational harmonic normal modes (IR and Raman band wavenumbers and intensities). Experimentally obtained Raman...

  4. A Hydrogen Ion-Selective Poly(Vinyl Chloride) Membrane Electrode Based on Calix[4]arene as a Perchlorate Ion-Selective Electrode

    OpenAIRE

    CANEL, Esin; ERDEN, Sevcan; ÖZEL, Ayça DEMİREL; MEMON, Sahahabuddin

    2008-01-01

    A hydrogen ion-selective electrode was prepared using 5,11,17,23-tetra-tert-butyl-25,26,27,28-tetracyanometoxy-calix[4]arene and the possibility of its use as a perchlorate ion-selective electrode was investigated using its characteristic of becoming perchlorate sensitive in acidic regions. The electrode of the optimum characteristic had a composition of 1% ionophore, 66% o-NPOE, and 33% PVC. This electrode exhibited a linear response over the range 1.0 \\times 10-1-1.0 \\times 10-5 M o...

  5. Examining the Critical Roles of Protons in Facilitating Oxidation of Chloride Ions by Permanganates: A Cluster Model Study

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jian; Sun, Zhenrong; Wang, Xue B.

    2015-06-18

    The oxidation power of permanganates (MnO4–) is known to be strongly dependent on pH values, and is greatly enhanced in acidic solutions, in which, for example, MnO4– can even oxidize Cl– ions to produce Cl2 molecules. Although such dependence has been ascribed due to the different reduced states of Mn affordable in different pH media, a molecular level understanding and characterization of initial redox pair complexes available in different pH solutions is very limited. Herein, we report a comparative study of [MnO4]– and [MnO4•Sol]– (Sol = H2O, KCl, and HCl) anion clusters by negative ion photoelectron spectroscopy (NIPES) and theoretical computations to probe chemical bonding and electronic structures of [MnO4•Sol]– clusters, aimed to obtain a microscopic understanding of how MnO4– interacts with surrounding molecules. Our study shows that H2O behaves as a solvent molecule, KCl is a spectator bound by pure electrostatic interactions, both of which do not influence the MnO4– identity in their respective clusters. In contrast, in [MnO4•HCl]–, the proton is found to interact with both MnO4– and Cl– with appreciable covalent characters, and the frontier MOs of the cluster are comprised of contributions from both MnO4– and Cl– moieties. Therefore the proton serves as a chemical bridge, bringing two negatively charged redox species together to form an intimate redox pair. By adding more H+ to MnO4–, the oxygen atom can be taken away in the form of a water molecule, leaving MnO4– as an electron deficient MnO3+ species, which can subsequently oxidize Cl– ions.

  6. 海洋水下区喷射混凝土中氯离子扩散性能研究%Experimental research on chloride ion erosion of shotcret in the marine underwater area

    Institute of Scientific and Technical Information of China (English)

    周宇; 牛荻涛; 王家滨

    2014-01-01

    Sprayed concrete structure is an important part of tunnel support.Located in the marine environment tunnel project is bound to suffer the erosion of chloride ions.Amethod to simulate the indoor soaking underwater marine environment to spray concrete chloride ion diffusion performance difference with ordinary concrete core,concrete way affect the main chloride diffusion of concrete performance.The test results show that construction methods on the performance of concrete resistance to chloride ion penetration significantly.Compared to ordinary concrete,shotcrete depth slightly largercapillary adsorption zone,the chloride ion concentration peak of about 2.51 times that of ordinary concrete,the larger chloride ion diffusion rate.After the addition of steel fibers ,sprayed concrete resistance to chloride ion pene-tration increased.Fick's second law onthe use of sprayed concrete in chloride ion content in non-linear fitting,with good correlation,and the initial establishment of the sprayed concrete and ordinary concrete chloride ion diffusion coefficient of relationship.%喷射混凝土结构是隧道支护的重要组成部分。位于海洋环境中的隧道工程,势必遭受氯离子的侵蚀。采用室内浸泡的方法模拟海洋水下环境,以喷射混凝土与普通混凝土中氯离子扩散性能差异为核心,主要研究混凝土施工方式对混凝土中氯离子扩散性能的影响。试验结果表明:施工方式对混凝土的抗氯离子渗透性能影响显著。相对于普通混凝土,喷射混凝土毛细吸附区深度略大,氯离子浓度峰值约为普通混凝土的2.51倍,氯离子扩散速率较大。加入钢纤维后,喷射混凝土抗氯离子渗透性能有所提高。运用Fick第二定律对喷射混凝土中氯离子含量进行非线性拟合,具有良好相关性,并初步建立了喷射混凝土与普通混凝土氯离子扩散系数的关系。

  7. Determination of the hydrolysis constants of Europium (III), in ion strength media 4, 5 and 6 M NaClO{sub 4} at 303 K; Determinacion de las constantes de hidrolisis del Europio (III), en medios de fuerza ionica 4, 5 y 6 M de NaClO{sub 4} a 303 K

    Energy Technology Data Exchange (ETDEWEB)

    Alvarado B, A.; Jimenez R, M.; Solache R, M. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1999-07-01

    This work was made with the purpose to complete information about the hydrolysis constants of Europium (III) in high ion strength media. So it was determined at a ion forces media 4, 5 and 6 M of sodium perchlorate at 303 K. The method used was the potentiometric with the aid of the Super quad computer program. In high ion strength media, the measurements of p H do not correspond directly to negative logarithm of the concentration of hydrogen ions, by this it is necessary to calibrate the electrode in these conditions. The Europium was hydrolized at pC{sub H} values greater 6 in all cases. The potentiometric method used under the described experimental conditions is adequate to determine the hydrolysis constants of Europium (III). According to the results and diagrams of chemical species of Europium obtained we can conclude that the hydrolysis constants, differ by its distribution but not in its identity. (Author)

  8. Naked eye sensor on polyvinyl chloride platform of chromo-ionophore molecular assemblies: A smart way for the colorimetric sensing of toxic metal ions

    Energy Technology Data Exchange (ETDEWEB)

    Prabhakaran, Deivasigamani; Nanjo, Hiroshi [Research Centre for Compact Chemical Process, National Institute of Advanced Industrial Science and Technology (AIST), Tohoku, 4-2-1 Nigatake, Miyagino-Ku, Sendai 983 8551 (Japan); Matsunaga, Hideyuki [Research Centre for Compact Chemical Process, National Institute of Advanced Industrial Science and Technology (AIST), Tohoku, 4-2-1 Nigatake, Miyagino-Ku, Sendai 983 8551 (Japan)], E-mail: hide.matsunaga@aist.go.jp

    2007-10-03

    We demonstrate the possibility of fabricating a simple, naked eye colorimetric sensor miniature, using chromo-ionophore molecular assemblies anchored on polyvinyl chloride (PVC) surface. The ion-sensing probe (4-n-dodecyl-6-(2-thiazolylazo)-resorcinol) provides a better efficiency with PVC platform in developing a series of colour transitions, while targeting trace levels of Cd{sup 2+}, Pb{sup 2+} and Hg{sup 2+}. The physical properties of the film sensor are controlled by measuring the probe isotherm plot. The surface morphology and molecular composition of the solid-state optical sensor are characterized using X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The changes in sensor's optical intensity and its response time for the target analytes are followed by absorption spectroscopy. High speed of response (t {<=} 5 min) and confidence in determination of analytes from chemically complex matrices has been achieved, using simulated synthetic mixtures and spiked real environmental samples, with a relative standard deviation of <3.9%. The proposed method offers consistent data reproducibility and reliability, with a detection limit of 0.031, 0.025 and 0.034 {mu}M, for Cd{sup 2+}, Pb{sup 2+} and Hg{sup 2+} ions, respectively. The sensor strips are reversible and reusable without any change in the sensing efficiency, up to four cycles. The signal response observed with the proposed method is consistent between sensors, and also are stable over time.

  9. Compressive strength and resistance to chloride ion penetration and carbonation of recycled aggregate concrete with varying amount of fly ash and fine recycled aggregate.

    Science.gov (United States)

    Sim, Jongsung; Park, Cheolwoo

    2011-11-01

    Construction and demolition waste has been dramatically increased in the last decade, and social and environmental concerns on the recycling have consequently been increased. Recent technology has greatly improved the recycling process for waste concrete. This study investigates the fundamental characteristics of concrete using recycled concrete aggregate (RCA) for its application to structural concrete members. The specimens used 100% coarse RCA, various replacement levels of natural aggregate with fine RCA, and several levels of fly ash addition. Compressive strength of mortar and concrete which used RCA gradually decreased as the amount of the recycled materials increased. Regardless of curing conditions and fly ash addition, the 28 days strength of the recycled aggregate concrete was greater than the design strength, 40 MPa, with a complete replacement of coarse aggregate and a replacement level of natural fine aggregate by fine RCA up to 60%. The recycled aggregate concrete achieved sufficient resistance to the chloride ion penetration. The measured carbonation depth did not indicate a clear relationship to the fine RCA replacement ratio but the recycled aggregate concrete could also attain adequate carbonation resistance. Based on the results from the experimental investigations, it is believed that the recycled aggregate concrete can be successfully applied to structural concrete members. PMID:21784626

  10. Innovative leaching of cobalt and lithium from spent lithium-ion batteries and simultaneous dechlorination of polyvinyl chloride in subcritical water.

    Science.gov (United States)

    Liu, Kang; Zhang, Fu-Shen

    2016-10-01

    In this work, an effective and environmentally friendly process for the recovery of cobalt (Co) and lithium (Li) from spent lithium-ion batteries (LIBs) and simultaneously detoxification of polyvinyl chloride (PVC) in subcritical water was developed. Lithium cobalt oxide (LiCoO2) power from spent LIBs and PVC were co-treated by subcritical water oxidation, in which PVC served as a hydrochloric acid source to promote metal leaching. The dechlorination of PVC and metal leaching was achieved simultaneously under subcritical water oxidation. More than 95% Co and nearly 98% Li were recovered under the optimum conditions: temperature 350°C, PVC/LiCoO2 ratio 3:1, time 30min, and a solid/liquid ratio 16:1 (g/L), respectively. Moreover, PVC was completely dechlorinated at temperatures above 350°C without any release of toxic chlorinated organic compounds. Assessment on economical and environmental impacts revealed that the PVC and LiCoO2 subcritical co-treatment process had significant technical, economic and environmental benefits over the traditional hydrometallurgy and pyrometallurgy processes. This innovative co-treatment process is efficient, environmentally friendly and adequate for Co and Li recovery from spent LIBs and simultaneous dechlorination of PVC in subcritical water. PMID:27209515

  11. Molecular dynamics simulation study of ionic hydration and ion association in dilute and 1 molal aqueous sodium chloride solutions from ambient to supercritical conditions

    Science.gov (United States)

    Driesner, T.; Seward, T. M.; Tironi, I. G.

    1998-09-01

    The increasing demand for accurate equations of state of fluids under extreme conditions and the need for a detailed microscopic picture of aqueous fluids in some areas of geochemistry (e.g., mineral dissolution/precipitation kinetics) potentially make molecular dynamics (MD) simulations a powerful tool for theoretical geochemistry. We present MD simulations of infinitely dilute and 1 molal aqueous NaCl solutions that have been carried out in order to study the systematics of hydration and ion association over a wide range of conditions from ambient to supercritical and compare them to the available experimental data. In the dilute case, the hydration number of the Na + ion remains essentially constant around 5.5 from ambient to supercritical temperatures when the density is kept constant at 1 g cm -3 but decreases to below 5 along the liquid-vapor curve. In both cases, the average ion-first shell water distance decreases by about 0.03 Å from ambient to near critical temperatures. The Cl - ion shows a slight expansion of the first hydration shell by about 0.02 Å from ambient to near critical temperatures. The geometric definition of the first hydration shell becomes ambiguous due to a shift of the position of the first minimum of the Cl-O radial distribution function. In the case of the 1 molal solution, the contraction of the Na + first hydration shell is similar to that in the dilute case whereas the hydration number decreases drastically from 4.9 to 2.8 due to strong ion association. The released waters are replaced on a near 1:1 basis by chloride ions. Polynuclear clusters as predicted by Oelkers and Helgeson (1993b) are observed in the high temperature systems. The hydration shell of the Cl --ion shows significant deviation from the behavior in dilute systems, that is, at near vapor saturated conditions, the expansion of the hydration shell is significantly larger (0.12 Å from ambient to near critical temperatures). Due to a very large shift of the first

  12. Erosion Prediction of Chloride Ions in Existing Concrete under the Natural Tidal Environment by the Natural Diffusion Method%自然扩散法预测感潮环境下混凝土氯离子侵蚀

    Institute of Scientific and Technical Information of China (English)

    张俊芝; 郑辉; 周建民; 王梁英; 刘华挺

    2011-01-01

    通过对自然感潮环境下混凝土的自由氯离子浓度分布的分析,研究了既有混凝土氯离子侵蚀的特征及扩散特性,采用室内自然扩散法进行了模拟扩散试验,并根据Fick第二定律和Monte Carlo法分析了既有混凝土和试验混凝土的扩散参数及钢筋初始锈蚀时间.结果表明:自然环境下混凝土的氯离子侵蚀存在明显的对流区,自然扩散法的氯离子扩散系数大于自然环境下2个数量级,模拟混凝土中钢筋表面的自由氯离子浓度是自然环境下实际浓度的2倍,钢筋初始锈蚀时间是实际的240倍.%Characteristics of erosion and diffusion of free chloride ions in existing concrete are studied through analysis for chloride ion concentration distribution of concrete in the natural tidal environment, a simulation experiment for chloride ion diffusion by the indoor natural diffusion method is tested, diffusion parameters and the initial corrosion time of steel bar in concrete of existing concrete and experimental concrete are analyzed on the basis of Fick's second law and the Monte Carlo method. The experimental and analysis results show that there are obvious convective region of chloride ion ingress in the natural environment, the chloride diffusion coefficient measured by the natural diffusion method is two orders of magnitude larger than that in the natural tidal environment, and free chloride ion concentration of reinforcement surface in simulated concrete is double of actual concentration of concrete in the natural tidal environment,initial time of corrosion of steel bar in experimental concrete is 240 times higher than concrete in the natural environment.

  13. Nuevas determinaciones de isótopos estables para Tierra del Fuego

    OpenAIRE

    Guichón, Ricardo Aníbal; Borrero, Luis Alberto; Prieto, Luis A.; Cárdenas, Pedro; Tykot, Robert

    2001-01-01

    Se presentan los resultados del análisis de isótopos estables (d 13C y d 15N sobre colágeno, d 13C sobre apatita) de 8 muestras óseas procedentes de Tierra del Fuego que, junto con 15 determinaciones previas, informan sobre la variación en la subsistencia de poblaciones de cazadores-recolectores. Se observa que los valores más "marítimos" se encuentran en el conjunto Sudeste de la Isla Grande. Por otra parte, los más "continentales" se encuentran en el conjunto Norte de la Isla Grande. Es int...

  14. Thermodynamic properties of ions in solutions of sodium and potassium chlorides in H2O-DMSO and D2O-DMSO mixtures of 278-323 K

    International Nuclear Information System (INIS)

    Thermodynamic characteristics of sodium and potassium chlorides ion solvation in mixtures of water and heavy water with dimethylsulfoxide have been obtained from data on temperature dependence of the standard e.m.f. of circuits without transfer. Regularities in their change depending on cation nature, temperature and composition of mixed solvent have been considered. Isotope effect in the Gibbs free energy of ΣNa+, Cl- and ΣK+, Cl- solvation has been calculated. 20 refs.; 3 figs.; 2 tabs

  15. Functional modulation of cerebral gamma-aminobutyric acidA receptor/benzodiazepine receptor/chloride ion channel complex with ethyl beta-carboline-3-carboxylate: Presence of independent binding site for ethyl beta-carboline-3-carboxylate

    Energy Technology Data Exchange (ETDEWEB)

    Taguchi, J.; Kuriyama, K. (Kyoto Prefectural Univ. of Medicine (Japan))

    1990-05-01

    Effect of ethyl beta-carboline-3-carboxylate (beta-CCE) on the function of gamma-aminobutyric acid (GABA)A receptor/benzodiazepine receptor/chloride ion channel complex was studied. Beta-CCE noncompetitively and competitively inhibited (3H)flunitrazepam binding to benzodiazepine receptor, but not (3H)muscimol binding to GABAA receptor as well as t-(3H)butylbicycloorthobenzoate (( 3H) TBOB) binding to chloride ion channel, in particulate fraction of the mouse brain. Ro15-1788 also inhibited competitively (3H) flunitrazepam binding. On the other hand, the binding of beta-(3H)CCE was inhibited noncompetitively and competitively by clonazepam and competitively by Ro15-1788. In agreement with these results, benzodiazepines-stimulated (3H)muscimol binding was antagonized by beta-CCE and Ro15-1788. Gel column chromatography for the solubilized fraction from cerebral particulate fraction by 0.2% sodium deoxycholate (DOC-Na) in the presence of 1 M KCl indicated that beta-(3H)CCE binding site was eluted in the same fraction (molecular weight, 250,000) as the binding sites for (3H)flunitrazepam, (3H)muscimol and (3H)TBOB. GABA-stimulated 36Cl- influx into membrane vesicles prepared from the bovine cerebral cortex was stimulated and attenuated by flunitrazepam and beta-CCE, respectively. These effects of flunitrazepam and beta-CCE on the GABA-stimulated 36Cl- influx were antagonized by Ro15-1788. The present results suggest that the binding site for beta-CCE, which resides on GABAA receptor/benzodiazepine receptor/chloride ion channel complex, may be different from that for benzodiazepine. Possible roles of beta-CCE binding site in the allosteric inhibitions on benzodiazepine binding site as well as on the functional coupling between chloride ion channel and GABAA receptor are also suggested.

  16. Functional modulation of cerebral gamma-aminobutyric acidA receptor/benzodiazepine receptor/chloride ion channel complex with ethyl beta-carboline-3-carboxylate: Presence of independent binding site for ethyl beta-carboline-3-carboxylate

    International Nuclear Information System (INIS)

    Effect of ethyl beta-carboline-3-carboxylate (beta-CCE) on the function of gamma-aminobutyric acid (GABA)A receptor/benzodiazepine receptor/chloride ion channel complex was studied. Beta-CCE noncompetitively and competitively inhibited [3H]flunitrazepam binding to benzodiazepine receptor, but not [3H]muscimol binding to GABAA receptor as well as t-[3H]butylbicycloorthobenzoate [( 3H] TBOB) binding to chloride ion channel, in particulate fraction of the mouse brain. Ro15-1788 also inhibited competitively [3H] flunitrazepam binding. On the other hand, the binding of beta-[3H]CCE was inhibited noncompetitively and competitively by clonazepam and competitively by Ro15-1788. In agreement with these results, benzodiazepines-stimulated [3H]muscimol binding was antagonized by beta-CCE and Ro15-1788. Gel column chromatography for the solubilized fraction from cerebral particulate fraction by 0.2% sodium deoxycholate (DOC-Na) in the presence of 1 M KCl indicated that beta-[3H]CCE binding site was eluted in the same fraction (molecular weight, 250,000) as the binding sites for [3H]flunitrazepam, [3H]muscimol and [3H]TBOB. GABA-stimulated 36Cl- influx into membrane vesicles prepared from the bovine cerebral cortex was stimulated and attenuated by flunitrazepam and beta-CCE, respectively. These effects of flunitrazepam and beta-CCE on the GABA-stimulated 36Cl- influx were antagonized by Ro15-1788. The present results suggest that the binding site for beta-CCE, which resides on GABAA receptor/benzodiazepine receptor/chloride ion channel complex, may be different from that for benzodiazepine. Possible roles of beta-CCE binding site in the allosteric inhibitions on benzodiazepine binding site as well as on the functional coupling between chloride ion channel and GABAA receptor are also suggested

  17. 自动电位滴定法快速测定铝箔生产液中的氯离子%Automtic potentiometric titration determinated chloride ions in electrolyte

    Institute of Scientific and Technical Information of China (English)

    林庆宇; 张志; 罗杨合; 练洁婷

    2011-01-01

    利用自动电位滴定仪,在体积分数为80%的丙酮介质中,以Ag电极为指示电极,双盐桥甘汞电极为参比电极,对铝箔生产液中Cl-进行非水滴定,方法的电位突跃明显,电极响应速度较快,SO42-、Cu2+、Fe3+及可能存在其他离子均对测定结果无影响,实现了自动电位滴定法快速测定铝箔生产过程液中Cl-的含量,结果表明本法是一种测定Cl-含量的有效方法.%Using automatic potentiometric titration, chlorine ions in aluminum electrolyte was determined at 80% acetone medium, with the silver electrode as indicator electrode, double salt bridge calomel electrode as reference electrode. The end point jumped of method over 500mV, the electrode responsed faster. Sulfate, copper ions, iron ions and other ions were no effect on the determination. The result showed that content of chloride could be achieved quickly by automatic potentiometric titration. It is an effective way to determine of industry chloride ion.

  18. Sensitivity Analysis of Chloride Ion Diffusion in Concrete Subjected to Marine Environment%海工环境混凝土中氯离子扩散敏感性分析

    Institute of Scientific and Technical Information of China (English)

    郝风田; 路影

    2013-01-01

    The sufficient attention may be paid attention to the durability of reinforced concrete structure all over the world at present .The concrete structures would be subjected to chloride ingress ,resulting in the corrosion of reinforcing bars ,inducing early deterioration and losing their durability ,and this is a main problem in engineering practices .Based on the second Fick’s law ,and taking into account the surface chloride concentration ,temperature ,water cement ratio , and initial chloride content ,the chloride ion diffusion is calculated and analyzed here .The sensitivity analysis shows that the influence factors of surface chloride concentration ,temperature ,water cement ratio of concrete are obvious ,and the influence of initial chloride content is weaker .%混凝土结构耐久性问题是当今世界普遍关注的问题。由于氯离子侵蚀,导致钢筋锈蚀,使结构发生早期破坏,丧失了结构的耐久性能,已成为实际工程中的重要问题。基于 Fick 第二定律,分别考虑表面氯离子浓度、温度、水灰比、初始氯离子含量,计算氯离子扩散。敏感性分析表明表面氯离子浓度、温度、水灰比对混凝土中氯离子扩散影响较大,初始氯离子含量影响较小。

  19. Effect of volume fraction on chloride ion diffusion coefficient of grade structure concrete%体积分数对梯度结构混凝土扩散系数影响研究

    Institute of Scientific and Technical Information of China (English)

    温小栋; 干伟忠; 谷伟; 陈旭波

    2013-01-01

    通过室内氯离子侵蚀加速试验及氯离子分布测试,结合Fick第2定理拟合出梯度结构混凝土(GSC)的氯离子浓度扩散系数,以研究面层体积分数、加速试验龄期对扩散系数的影响;采用压汞技术测试面层材料与结构层材料的孔结构参数,分析氯离子扩散系数与孔结构之间的关系.结果表明:GSC体系的氯离子扩散系数随面层体积分数的增加而下降,并逐渐趋于平缓;GSC体系氯离子扩散系数则随加速试验龄期的延长而减小,最后也趋于稳定;与面层体积分数V=0试件相比,其它GSC试件具有更大的时间衰减系数值,说明其抵抗氯离子侵蚀的能力更好.最后根据相似性理论,建立了考虑面层体积分数变化的GSC氯离子扩散系数时变模型,分析显示,与结构层材料相比,面层材料具有较低的孔隙率及最可几孔径,使得孔的曲折性越大、连通性越低,因而面层材料具有更低的扩散系数.%Combined with the Fick' s Second Law the chloride ion diffusion coefficients of gradient structure concrete (GSC) were calculated for studying the effect of surface-layer volume fractions and accelerating period,by conducting the Chloride ion migration rapid test and determining the distribution of chloride ions.At the same time,the pore structure parameters were obtained by mercury intrusion porosimetry to study the relationship between chloride ion diffusion coefficient and pore structure parameters.The results show that chloride ion diffusion coefficient of the GSC is reduced with the increase of volume fractions of the surface-layer,and reaches a steady state finally; the chloride ion diffusion coefficient in GSC gradually decreases along with the increase of accelerating period,and also reaches a steady state finally.Compared with the specimens with 0 % volume fractions of surface-layer,the others with a higher volume fraction have a greater time decay coefficient of diffusion coefficient

  20. Green process to recover magnesium chloride from residue solution of potassium chloride production plant

    Institute of Scientific and Technical Information of China (English)

    Lin WANG; Yunliang HE; Yanfei WANG; Ying BAO; Jingkang WANG

    2008-01-01

    The green process to recover magnesium chlor-ide from the residue solution of a potassium chloride pro-duction plant, which comes from the leach solution of a potash mine in Laos, is designed and optimized. The res-idue solution contains magnesium chloride above 25 wt-%, potassium chloride and sodium chloride together below 5 wt-% and a few other ions such as Br-, SO2-4and Ca2+. The recovery process contains two steps: the previous impurity removal operation and the two-stage evapora-tion-cooling crystallization procedure to produce magnes-ium chloride. The crystallized impurity carnallite obtained from the first step is recycled to the potassium chloride plant to recover the potassium salt. The developed process is a zero discharge one and thus fulfills the requirements for green chemical industrial production. The produced magnesium chloride is up to industrial criteria.

  1. EQCM study of the ECL quenching of the tris(2,2'-bipyridyl)ruthenium(II)/tris-n-propylamine system at a Au electrode in the presence of chloride ions

    International Nuclear Information System (INIS)

    Significant effect of chloride ions on the electrogenerated chemiluminescence (ECL) behavior of the ruthenium(II)tris(2,2'-bipyridine) (Ru(bpy)32+)/tri-n-propylamine (TPrA) system at a Au electrode was reported. At low concentrations (e.g., [Cl-] -]. At [Cl-] = 90 mM, ∼50% and 100% ECL inhibition was observed for the first and the second ECL wave, respectively. The electrogenerated gold-chloride complexes (AuCl2- and AuCl4-) which were verified using an electrochemical quartz-crystal microbalance (EQCM) method were found to be responsible for the ECL inhibition. This study suggests that care must be taken when a Au working electrode is used for ECL studies in chloride-containing buffer solutions (widely used in DNA probes) and/or with the commonly used chloride-containing reference electrodes since in these cases the ECL behavior may significantly disagree with that obtained using other electrodes and reaction media

  2. On the Nature of the Intermediates and the Role of Chloride Ions in Pd-Catalyzed Allylic Alkylations: Added Insight from Density Functional Theory

    DEFF Research Database (Denmark)

    Fristrup, Peter; Ahlquist, Mårten Sten Gösta; Tanner, David Ackland;

    2008-01-01

    The reactivity of intermediates in palladium-catalyzed allylic alkylation was investigated using DFT (B3LYP) calculations including a PB-SCRF solvation model. In the presence of both phosphine and chloride ligands, the allyl intermediate is in equilibrium between a cationic eta(3)-allylPd complex...... with two phosphine ligands, the corresponding neutral complex with one phosphine and one chloride ligand, and a neutral eta(1)-allylPd complex with one chloride and two phosphine ligands. The eta(1)-complex is unreactive toward nucleophiles. The cationic eta(3)-complex is the intermediate most...

  3. Determination of hydrolysis constants for gadolinium in ion strength media 2M of NaCl, NaClO{sub 4} and KCl at 303 K; Determinacion de las constanted de hidrolisis del gadolinio en los medios de fuerza ionica 2M de NaCl, NaClO{sub 4} y KCl, a 303 K

    Energy Technology Data Exchange (ETDEWEB)

    Serna M, S.; Jimenez R, M.; Solache R, M. [Instituto Nacional de Investigaciones Nucleares, Departamento de Quimica, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1999-07-01

    This work was made with the purpose to extend information about the hydrolysis constants of gadolinium (III) in ion strength media 2M of NaCl, NaClO{sub 4}, KCl at 303 K using the potentiometric method for this determination, and analysing starting from those data, the influence of anions and cations. It is concluded that the media which were determined the hydrolysis constants are very important and it is recommended the sodium perchlorate as the more adequate salt for those determinations. Also it was obtained the distribution diagrams of chemical species in each one of the media studied. (Author)

  4. Uses of complexone III and ion exchange resins in colorimetric determination with o-phenanthroline of Fe traces in uranium compounds; Aplicacion de la complexona III y resinas combadoras a la determinacion colorimetrica con orto-fenantro-lina de trazas de dhierro en compuesto de uranio

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez Cellini, R.; Ruiz Sanchez, F.

    1956-07-01

    The determination of small quantities of iron using o-phenanthroline, assumes the elimination of some cations interference by means of pH control before the formation of a coloured complex. We have eluded that difficulty by the connected action of complexones III and ion exchange. the previous forms quelate with the iron (III) with a stability constant high enough to permit the pass of an iron solution through a cation resin column without being fixed which never occurs with the interferer cations. Mercury is the only element with a similar stability, but it has been eliminated previously. (Author) 16 refs.

  5. Chloride ion transport in fly ash concrete under marine atmospheric environment%海洋大气中氯离子在粉煤灰混凝土中的传输规律

    Institute of Scientific and Technical Information of China (English)

    鲁彩凤; 袁迎曙; 季海霞; 姬永生

    2012-01-01

    为了实现海洋大气环境中粉煤灰混凝土耐久性使用寿命的预测,从氯离子在人工模拟海洋大气环境中粉煤灰混凝土中的传输试验出发,结合氯离子在非饱和多孔介质中的传输机理,研究海洋大气环境下混凝土内部微环境(微环境温度和相对湿度)及粉煤灰掺量对氯离子传输速率的影响程度,并与人工模拟海洋水下环境试验结果进行对比分析.研究结果表明:1)在海洋大气环境与海洋水下环境下,氯离子在粉煤灰混凝土中的扩散模型形式上一致,粉煤灰的掺人对氯离子传输能力有一定的影响,但不会改变氯离子在混凝土中的传输机理.2)当粉煤灰掺量一定时,微环境相对湿度越高(微环境温度一定),海洋大气环境氯离子扩散系数越大;但微环境温度(微环境相对湿度一定)对海洋水下环境和海洋大气环境中氯离子迁移的影响程度不同.3)粉煤灰掺量(微环境温度、相对湿度一定)对海洋水下环境和海洋大气环境氯离子扩散系数的影响规律不同.%The effect of micro-environment (temperature and relative humidity inside the concrete) and fly ash replacement on chloride ion transport in the fly ash concrete was analyzed from test results in artificial marine atmospheric zone and chloride diffusion mechanism in non-saturated porous media in order to predict durability service life. Then a comparative analysis between marine atmospheric environment and marine underwater environment was conducted. Results show that; l)the form of chloride diffusion model in fly ash concrete under atmosphere environment is consistent with that under underwater marine environment! the fly ash has a certain effect on chloride ion transport capacity, but it does not change the transport mechanism of chloride ion transport in fly ash concrete. 2) the higher the micro-environment relative humidity is (the same micro-environment temperature), the greater chloride ion

  6. Surface Chloride Concentration of Concrete under Shallow Immersion Conditions

    OpenAIRE

    Jun Liu; Kaifeng Tang; Dong Pan; Zongru Lei; Weilun Wang; Feng Xing

    2014-01-01

    Deposition of chloride ions in the surface layer of concrete is investigated in this study. In real concrete structure, chloride ions from the service environment can penetrate into concrete and deposit in the surface layer, to form the boundary condition for further diffusion towards the interior. The deposit amount of chloride ions in the surface layer is normally a function of time, rather than a constant. In the experimental investigation, concrete specimens with different mix proportions...

  7. The removal of radioactive radium (Ra226) from chloride liquors by columnar ion exchange in the presence of calcium, magnesium and iron cations

    International Nuclear Information System (INIS)

    The purpose of this work was to study the feasibility of controlling the discharge of soluble Ra226, in the presence of Ca, Mg and Fe cations in synthetic chloride effluents, by adsorption on cation exchange resins to decrease Ra226-concentrations to federal environmental levels of 10 pCi Ra226/litre. Environmentally acceptable effluents were produced from synthetic chloride feed liquors containing 10 ppm Ca, 5 ppm Mg, 120 ppm Fe plus 20,000 pCi Ra226/litre. Environmentally acceptable effluents were not produced, by cation exchange, from a synthetic chloride liquor containing 490 ppm Ca, 97 ppm Mg, 720 ppm Fe in addition to 20,000 pCi Ra226/litre. The mass interference of the Ca + Mg + Fe cation concentrations in the feed liquor was in over-powering competition, for resin sites, with the Ra226-cations. To obtain realistic data, the adsorption process should be reexamined using a chloride liquor produced under optimal chloride leaching conditions of an Elliot Lake uranium ore. This would, in all probability, reveal other cations unavailable in the synthetic chloride liquors

  8. 骨料对氯离子在水泥基复合材料中扩散系数的影响%Influence of Aggregates on Chloride Ion Diffusion Coefficient in Cement-Based Composite Materials

    Institute of Scientific and Technical Information of China (English)

    孙国文; 孙伟; 张云升; 刘志勇; 王彩辉

    2011-01-01

    To determine the influence of aggregates on chloride ion diffusion coefficient in cement-based composite materials, mortar and concrete specimens were cast with different aggregates, aggregate size distributions and aggregate volume fractions. Pore size distributions and chloride ion diffusion coefficients of the specimens were measured by mercury intrusion porosimetry test and steady-state accelerated migration test, respectively. The volume fraction of interracial transition zone (ITZ) could be calculated according to the mix proportions of specimens, size distribution of aggregates and ITZ thickness. The results show that the chloride diffusivity in cement-based composite materials is related to the chloride diffusion coefficient of matrix and ITZ, volume fraction of aggregate and ITZ. The volume fraction of ITZ is affected by the aggregate size distribution, the volume fraction of aggregate and thickness of ITZ. The presence of aggregates in cement-based materials might modify the pore structure of hardened cement paste,and its dilution effect and tortuosity effect could reduce chloride transport properties. The special microstmctures of ITZ could increase chloride transport. The influence of ITZ could be dominant to chloride diffusion in cement-based materials. Based on the experimental and analytical results, the approximate chloride ion diffusion coefficient of ITZ is 13.26 or 18.45 times greater than the matrix migration coefficient for mortar or concrete, respectively.%为了确定骨料对氯离子在水泥基复合材料中扩散系数的影响,利用压汞技术和稳态电迁移法分别对含不同类型、不同粒径分布、不同体积分数骨料的砂浆和混凝土试样,进行了孔结构和氯离子扩散系数的测试,并根据试样配合比、骨料的粒径分布以及界面过渡区(简称界面区)厚度进行了界面区体积分数计算,最后提出了界面区有效扩散系数的预测模型.结果表

  9. Chloride ion-driven transformation from Ag3PO4 to AgCl on the hydroxyapatite support and its dual antibacterial effect against Escherichia coli under visible light irradiation.

    Science.gov (United States)

    Hong, Xiaoting; Li, Min; Shan, Shengdao; Hui, K S; Mo, Mingyue; Yuan, Xiaoli

    2016-07-01

    Visible light-driven photocatalytic inactivation of Escherichia coli was performed using hydroxyapatite-supported Ag3PO4 nanocomposites (Ag3PO4/HA). The antibacterial performance was evaluated by the methods of zone of inhibition plates and minimum inhibitory concentration test. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were employed to investigate the instability and transformation of the nanocomposite by comparing the crystalline, phase, and the morphology before and after exposure to Luria-Bertani culture medium under visible light irradiation. Ag3PO4 nanoparticles on the support were found to be shortly transformed into AgCl due to high chloride concentration of Luria-Bertani culture medium. The AgCl/HA nanocomposite showed both excellent intrinsic antibacterial performance contributed by the released silver ions and visible light-induced photocatalytic disinfection toward E. coli cells. This dual antibacterial function mechanism was validated by trapping the hydroxyl free radical and detecting the silver ions during the photocatalytic antibacterial process. The morphological change of E. coli cells in different reaction intervals was obtained by scanning electron microscopy (SEM) to complementally verify photocatalytic inactivation of E. coli. This work suggests that an essential comparison study is required for the antibacterial materials before and after the photocatalytic inactivation of bacterial cells using Ag3PO4 nanoparticles or Ag3PO4-related nanocomposites in mediums containing high-concentration chloride ions. PMID:27026549

  10. 改性偏高岭土复合粉煤灰对混凝土抗渗性能的影响%Effect of Modified Metakaolin and Fly Ash on Permeability of Concrete Resistance to Chloride Ion

    Institute of Scientific and Technical Information of China (English)

    水中和; 王康; 陈伟; 孔贇

    2012-01-01

    将经改性的偏高岭土(MMK)与超细粉煤灰(FA)复合,以低于10%的总掺量内掺到混凝土中,研究了掺入前后和不同掺量对混凝土的工作性能、力学性能、电通量和氯离子扩散系数的影响.并运用压汞、TG-DSC耦合分析和SEM照片等方法,对其影响机理进行了探讨.结果表明:低掺量改性偏高岭土复合粉煤灰对混凝土抗氯离子渗透性能有显著的改善;对混凝土工作性能影响较小,能提高混凝土各龄期抗压强度;可以优化混凝土的孔结构和水泥石-集科界面过渡区.%The effect of modified metakaolin ( MMK) blended with fine fly ash (FA) on permeability of concrete resistance to chloride ion, where the content of MMK and FA mixture was below 10% by weight, has been investigated. Mercury intrusion, TG-DSC analysis and SEM were used to study the mechanism. The collapsed slump, compressive strength, electric flux and chloride diffusion coefficient of concrete mixes containing four different mixtures were tested. The experimental results show that the permeability resistance to chloride ion of concrete significantly increases with the incorporation of MMK and FA mixtures. MMK and FA mixtures have minor effect on the collapsed slump of concrete, while they improve the compressive strength at 3 d, 7 d and 28 d. Also MMK and FA mixtures modify the pore structure and optimize the interfacial transition zone(ITZ).

  11. A mathematical model for electrochemical chloride removal from marine cast iron artifacts

    Institute of Scientific and Technical Information of China (English)

    Weizhen OUYANG; Xia CAO; Ning WANG

    2009-01-01

    The aim of this article was to theoretically study diffusion and migration of chlo-ride ions during electrochemical chloride removal. The proposed model would enable optimization of its application by predicting the optimal treatment time and current combination. A mathematical model for simulating the transport behavior of chloride ions was developed by consideration of diffusion and migration of chloride ions when a constant DC current density was applied through the marine cast iron artifacts. The corresponding tests were conducted to validate the mathematical model. This model predicted the data of the extraction ratio of the chloride ion that correlated satisfac-torily with the experimental values. An important issue in electrochemical chloride removal was to understand how chloride ions moved, taking account of diffusion and migration of chloride ions and the release of binding chloride ions. The effects of the treatment time, externally applied current density, chloride diffusion coefficient, and rate constant of release of binding chloride ion on chloride removal are studied. The specific quantitative details applied to one-dimensional model were discussed here. This article has proposed a mathematical model for the first time, which was showed to be a useful tool that can reveal the ionic transport mechanism and optimize the application during electrochemical chloride removal.

  12. Design of a Remote Monitoring System for Evaluation of Corrosión in Reinforced Concrete Structures under Chloride Ion Attack

    OpenAIRE

    Roa-Rodríguez Guillermo; Aperador-Chaparro William; Delgado-Tobón Emilio

    2015-01-01

    In this paper it was designed and built a remote monitoring equipment that allows to obtain the corrosion potential in reinforcing steels embedded in reinforced concrete, which were previously subjected to chloride attack in a hostile environment. The monitoring system, based on ASTM standard C876-91, determines from 0% to 100% the probability of corrosion on the samples tested. The system provides ease of perform field installation, if there is cellular network coverage, and m...

  13. Effect of the chloride ions on the hydrolysis of praseodymium in a 2M ion force media; Efecto de los iones cloruro sobre la hidrolisis del praseodimio en medio de fuerza ionica 2M

    Energy Technology Data Exchange (ETDEWEB)

    Lopez G, H.; Jimenez R, M.; Solache R, M.; Rojas H, A. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2004-07-01

    The constants of the product of solubility and the first of hydrolysis were determined of the Praseodymium in media 2M of NaClO{sub 4} and 2M of NaCl, to 303 K and under conditions free of CO{sub 2}. The diagram of solubility was obtained (pPr{sub (ac)} - pC{sub H}), by means of a radiochemical method and with it was established the pC{sub H} that limit the saturation and non saturation areas; that diagram allowed, also, to calculate the constant of the product of solubility. Also, it was adjusted with the polynomial of solubility equation, that it allowed to determine and to check the values of the constants of the product of solubility and the first of hydrolysis. Independently, it was determined the first constant of hydrolysis of the element, by means of potentiometric titrations whose data were treated with the computer program named SUPERQUAD and with the adjustment of the equation of the average number of bonds. It was also calculates the log constant {beta}{sub Pr,Cl} of the specie PrCI{sup 2+} starting from the hydrolysis constants obtained in the perchlorate and chloride media. (Author)

  14. Estimating the chloride transport in cement paste

    OpenAIRE

    Princigallo, A.

    2012-01-01

    A method was developed to measure the diffusion coefficient of chloride ions in cement paste based on an analytical solution to Fick’s 2nd law in a cylindrical coordinate system. This natural method yielded diffusivity results within as little as a month. Testing time was reduced by exploiting the three-dimensional inward flux in the specimen. In an attempt to determine the saturation concentration, dense portland cement pastes were exposed to a concentrated chloride solution. The method prov...

  15. 废弃玻璃骨料混凝土氯离子扩散的QR法%QR method for the chloride ion diffusion of the waste glass aggregate concrete

    Institute of Scientific and Technical Information of China (English)

    刘光焰; 范文; 王晓峰

    2014-01-01

    在Fick第二定律的基础上,根据废弃玻璃骨料混凝土中的氯离子基本方程,提出了用于废弃玻璃骨料混凝土氯离子扩散问题的QR法,建立了基于常扩散系数的氯离子扩散的QR法模型。通过算例,可知QR法具有很好的计算效率和很高的计算精度,同时,与其他方法相比,可以更好地计算非规则边界的氯离子扩散问题,而且该法集有限元法、有限条法、无限元法和样条有限点法的优点于一体,克服了有限元及有限条法的缺点,不仅计算简单,而且精度高,大大降低了离散未知量,降低了计算工作量,保证了计算精度和效率。%On base of the Fick's second law,the QR method for the question of the chloride ion diffusion of the waste glass aggregate concrete was researched according to the basic equation of the chloride ions and QR method.Through example ,research showed that QR method has good computational efficiency and high accuracy,while compared with other methods,it can better calculate non-regular boundary of the chloride ion diffusion problem.Moreover,the QR method gather many advantages of finite element method,finite strip method,infinite element method and the spline finite point and overcome shortcomings of the finite element and finite strip method.It is not only simple but also highly accurate,and it greatly reduces the discrete unknown variables and computational workload,and ensure the accuracy and efficiency.

  16. An insight into the passivation of cupronickel alloys in chloride environment

    Indian Academy of Sciences (India)

    J Mathiyarasu; N Palaniswamy; V S Muralidharan

    2001-02-01

    Cupronickels offer enhanced corrosion protection in marine environments by the formation of passive films on the surface. Cyclic voltammetric studies were carried on cupronickels in chloride solutions at H 6.3 to understand the role of chloride ions in passive film formation. Increase in nickel content of the alloy and of chloride ions in solution decreases film resistance. Chloride ions take part in reduction of the passive film to copper. A solid-state model for passive film formation involving chloride ions has been attempted.

  17. Influence of chloride admixtures on cement matrix durability

    International Nuclear Information System (INIS)

    The influence of various inorganic salts, as chloride admixtures to Portland cement, on the mechanical properties and the durability of the matrix has been studied. The salts used in this study are chromium, nickel and cadmium chlorides. Improved compressive strength values are obtained which have been correlated to the stable metal hydroxide formation in high pH environment. Under static water conditions at 500C, hydrolyzed chloride ions exhibit adverse effects on the matrix durability through rapid release of calcium as calcium chloride in the initial period of leaching. On the contrary, enhanced matrix durability is obtained on long term leaching in the case of cement containing chromium chloride

  18. Determination of bromide, chloride, fluoride, nitrate and sulphate by ion chromatography: comparisons of methodologies for rainfall, cloud water and river waters at the Plynlimon catchments of mid-Wales

    Directory of Open Access Journals (Sweden)

    2007-01-01

    Full Text Available The results of determination of bromide, chloride, fluoride, nitrate and sulphate using ion chromatography (IC are compared with those obtained by colorimetric and inductively coupled plasma optical emission spectroscopy (ICPOES for rainfall, cloud water and stream waters in the Plynlimon experimental catchments of mid-Wales. For bromide, the concentrations determined by IC are lower than those for the colorimetric method used; the colorimetric method probably determined bromide plus organo-bromine compounds. It is suggested that the values determined by the colorimetric method be termed dissolved labile bromine (DLBr. The study shows that sulphate is the overriding form of sulphur in the waters. For chloride and nitrate, measurements by both methods approach a 1:1 relationship that is barely statistically significantly different from unity. For fluoride, the IC method gives lower values than the colorimetric, especially for the stream waters. However, the colorimetric method determines total fluorine so that a difference is to be expected (for example, fluoride strongly complexes with aluminium that is present, especially in the streamwater.

  19. Radiation crosslinking of poly(vinyl chloride) with trimethylolpropanetrimethacrylate. IV. Effect of diundecyl phthalate: dependence of physical properties on composition. [Electron beam ion sources

    Energy Technology Data Exchange (ETDEWEB)

    Bowmer, T.N.; Vroom, W.I.

    1983-11-01

    Blends of poly(vinyl chloride)(PVC) with polyfunctional monomers may be crosslinked by ionizing radiation. The physical properties of PVC blended with trimethylolpropanetrimethacrylate (TMPTMA) and diundecyl phthalate (DUP) were studied. The TMPTMA monomer crosslinked the blend by homopolymerization and/or grafting to PVC. The plasticizer, DUP, was chemically inert under irradiation but, by plasticizing the macromolecules and diluting the monomer, changed the kinetics extensively. Characteristics of the glass transitions and the tensile mechanical properties have been correlated with blend composition and radiation dose. Before irradiation, poly(vinyl chloride) was plasticized by both DUP and TMPTMA monomer. The increase in glass transition temperature and mechanical strength following irradiation to 5 Mrad was correlated with the TMPTMA content of the blend. Both the molecular structure of the network and the DUP content of the blend were factors in determining the physical properties of the final crosslinked blend. The molecular structure was determined by the kinetics of the crosslinking reactions, which in turn were determined by the blend composition. A molecular interpretation consistent with the physical properties, chemical kinetics, and mechanism of the crosslinking system has been presented. 24 figures, 2 tables.

  20. Intracellular chloride concentration of the mouse vomeronasal neuron

    OpenAIRE

    Kim, Sangseong; Ma, Limei; Unruh, Jay; McKinney, Sean; Yu, C. Ron

    2015-01-01

    Background The vomeronasal organ (VNO) is specialized in detecting pheromone and heterospecific cues in the environment. Recent studies demonstrate the involvement of multiple ion channels in VNO signal transduction, including the calcium-activated chloride channels (CACCs). Opening of CACCs appears to result in activation of VNO neuron through outflow of Cl− ions. However, the intracellular Cl− concentration remains undetermined. Results We used the chloride ion quenching dye, MQAE, to measu...

  1. Electrochemical behavior of lanthanum and yttrium ions in two molten chlorides with different oxoacidic properties: The eutectic LiCl-KCl and the equimolar mixture CaCl2-NaCl

    Directory of Open Access Journals (Sweden)

    Castrillejo Y.

    2003-01-01

    Full Text Available The electrochemical behavior of LaCl3 and YCl3 was studied in two molten chloride mixtures with different oxoacidic properties, the eutectic LiCl-KCl and the equimolar CaCl2-NaCl melt at different temperatures. The stable oxidation states of both elements have been found to be (III and (0 in both melts, and it was found that both La(III and Y(III cations were less solvated by the chloride ions in the calcium-based melt, which was explained by the stability of CaCl4 2- ions in that melt. Transient electrochemical techniques, such as cyclic voltammetry, chronopotentiometry and chronoamperometry were used in order to study the reaction mechanism and the transport parameters of electro active species at a tungsten electrode. The results showed that in the eutectic LiCl-KCl, the electro crystallization of lanthanum and yttrium seems to be the controlling electrochemical step while in CaCl2-NaCl this phenomenon has not been observed. That was explained in terms of the differences in the physicochemical properties of the systems, especially interfacial tensions. In the eutectic LiCl-KCl chronoamperometric studies indicated instantaneous and three dimensional nucleation and crystal growth of lanthanum and yttrium whatever the applied over potential of the rare earth metal is, whereas in the equimolar mixture CaCl2-NaCl, the corresponding electrochemical exchanges were found to be quasi-reversible, and the values of the kinetic parameters, K0 and α,were obtained for both reactions. Mass transport towards the electrode is a simple diffusion process, and the diffusion coefficients have been calculated. The validity of the Arrhenius law was also verified by plotting the variation of the logarithm of the diffusion coefficient versus 1/T.

  2. 缓凝剂对C50低氯离子混凝土性能的影响研究%Research on influence of retarders on the Performance of C50 low chloride ion concrete

    Institute of Scientific and Technical Information of China (English)

    徐长伟; 何桂春; 孟琦涵

    2014-01-01

    The influence of different kinds of retarder on the workability,volume change,strength,and hydration heat of C50 low chloride ion concrete were studied by using three kinds of retarders.Based on the design requirements of C50 high performance concrete,the content of chloride ion was controlled below 0.06%by adjusting and optimizing the mix proportion and the hydration heat was reduced by mixing right amount of fly ash.The results show that the fluidity loss can be effectively reduced and at the same time early volume deformation of concrete can be lowered without adverse effects on the late strength.Among the three kinds of retarders,the retarding effect of citric acid is stable.%采用三种缓凝剂来研究不同缓凝剂对C50低氯离子混凝土工作性、体积变化、强度和水化热的影响。基于C50高性能混凝土的设计要求,通过调整优化原料配比来实现混凝土中的氯离子含量在0.06%以下,并通过掺加适量的粉煤灰以达到降低水化热的目的。研究结果表明:掺加缓凝剂可以有效的减少混凝土的经时损失,同时降低混凝土早期体积变形,并对后期强度无不良影响。三种缓凝剂中,柠檬酸的缓凝效果比较稳定。

  3. Mass concentration and ion composition of coarse and fine particles in an urban area in Beirut: effect of calcium carbonate on the absorption of nitric and sulfuric acids and the depletion of chloride

    Science.gov (United States)

    Kouyoumdjian, H.; Saliba, N. A.

    2006-05-01

    Levels of coarse (PM10-2.5) and fine (PM2.5) particles were determined between February 2004 and January 2005 in the city of Beirut, Lebanon. While low PM mass concentrations were measured in the rainy season, elevated levels were detected during sand storms originating from Arabian desert and/or Africa. Using ATR-FTIR and IC, it was shown that nitrate, sulfate, carbonate and chloride were the main anionic constituents of the coarse particles, whereas sulfate was mostly predominant in the fine particles in the form of (NH4)2SO4. Ammonium nitrate was not expected to be important because the medium was defined as ammonium poor. In parallel, the cations Ca2+ and Na+ dominated in the coarse, and NH4+, Ca2+ and Na+ in the fine particles. Coarse nitrate and sulfate ions resulted from the respective reactions of nitric and sulfuric acid with a relatively high amount of calcium carbonate. Both CaCO3 and Ca(NO3)2 crystals identified by ATR-FTIR in the coarse particles were found to be resistant to soaking in water for 24 h but became water soluble when they were formed in the fine particles suggesting, thereby, different growth and adsorption phenomena. The seasonal variational study showed that nitrate and sulfate ion concentrations increased in the summer due to the enhancement of photochemical reactions which facilitated the conversion of NO2 and SO2 gases into NO3- and SO42-, respectively. While nitrate was mainly due to local heavy traffic, sulfates were due to local and long-range transport phenomena. Using the air mass trajectory HYSPLIT model, it was found that the increase in the sulfate concentration correlated with wind vectors coming from Eastern and Central Europe. Chloride levels, on the other hand, were high when wind originated from the sea and low during sand storms. In addition to sea salt, elevated levels of chloride were also attributed to waste mass burning in proximity to the site. In comparison to other neighboring Mediterranean countries, relatively

  4. Mass concentration and ion composition of coarse and fine particles in an urban area in Beirut: effect of calcium carbonate on the absorption of nitric and sulfuric acids and the depletion of chloride

    Directory of Open Access Journals (Sweden)

    H. Kouyoumdjian

    2006-01-01

    Full Text Available Levels of coarse (PM10-2.5 and fine (PM2.5 particles were determined between February 2004 and January 2005 in the city of Beirut, Lebanon. While low PM mass concentrations were measured in the rainy season, elevated levels were detected during sand storms originating from Arabian desert and/or Africa. Using ATR-FTIR and IC, it was shown that nitrate, sulfate, carbonate and chloride were the main anionic constituents of the coarse particles, whereas sulfate was mostly predominant in the fine particles in the form of (NH42SO4. Ammonium nitrate was not expected to be important because the medium was defined as ammonium poor. In parallel, the cations Ca2+ and Na+ dominated in the coarse, and NH4+, Ca2+ and Na+ in the fine particles. Coarse nitrate and sulfate ions resulted from the respective reactions of nitric and sulfuric acid with a relatively high amount of calcium carbonate. Both CaCO3 and Ca(NO32 crystals identified by ATR-FTIR in the coarse particles were found to be resistant to soaking in water for 24 h but became water soluble when they were formed in the fine particles suggesting, thereby, different growth and adsorption phenomena. The seasonal variational study showed that nitrate and sulfate ion concentrations increased in the summer due to the enhancement of photochemical reactions which facilitated the conversion of NO2 and SO2 gases into NO3- and SO42-, respectively. While nitrate was mainly due to local heavy traffic, sulfates were due to local and long-range transport phenomena. Using the air mass trajectory HYSPLIT model, it was found that the increase in the sulfate concentration correlated with wind vectors coming from Eastern and Central Europe. Chloride levels, on the other hand, were high when wind originated from the sea and low during sand storms. In addition to sea salt, elevated levels of chloride were also attributed to waste mass burning in proximity to the site. In comparison to other neighboring Mediterranean

  5. Osmotic properties of binary mixtures 1-butyl-1-methylpyrrolidinium dicyanamide and 1-methyl-3-octylimidazolium chloride with water: Effect of aggregation of ions

    International Nuclear Information System (INIS)

    Graphical abstract: Osmotic properties of binary mixture of two ionic liquids (ILs): 1-butyl-1-methyl pyrrolidinium dicyanamide and 1-methyl-3-octylimidazolium chloride with water was reported by using vapour pressure osmometry (VPO) method. - Highlights: • Osmotic properties of binary mixture of ionic liquids (ILs) with water by using vapour pressure osmometry (VPO) method. • The experimental osmotic coefficients were well correlated by Archer extension of Pitzer model. • From the experimental osmotic coefficient data the critical micellar concentration (cmc) of the ILs in water was estimated. • Mean molar activity coefficient and the excess Gibbs free energy was determine for the (ILs + water) binary mixture. - Abstract: In this work, the osmotic properties of the binary mixture of ionic liquids (ILs) and water were studied by using vapour pressure osmometry (VPO) method. We have used two ILs: 1-butyl-1-methyl pyrrolidinium dicyanamide and 1-methyl-3-octylimidazolium chloride. The aqueous solution of NaCl was used as the reference solution to precisely measure the osmotic coefficients of the above systems. We have calculated the activity of water in the above systems and the change of vapour pressure of water due to the addition of ILs in water. The experimental osmotic coefficients were correlated by the Archer extension of Pitzer model. The parameters of this Archer extension of Pitzer model were found from this data fitting. From the experimental osmotic coefficient value we have estimated the critical micellar concentration (cmc) of ILs in water. The experimental values of osmotic coefficient in the above systems were compared with the literature and the reason of variation was explained, in terms of the aggregation of ILs in water

  6. Evaluation of Ag/AgCI sensors for in-situ monitoring of freee chloride concentration in reinforced concrete structures

    OpenAIRE

    Pargar, F.; Koleva, D.A.; Copuroglu, O.; Koenders, E.A.B.; Breugel, K. van

    2014-01-01

    The level of free chloride concentration in reinforced concrete structures essentially determines the onset of steel corrosion initiation and further propagation. One of the well-known methods for monitoring free chloride concentration is using silver/silver chloride electrodes (Ag/AgCl). These electrodes are sensitive mainly to chloride ions and establish a certain electrochemical potential depending on the chloride ion activity in the environment. Although the functioning principles of thes...

  7. Evaluation of the susceptibility to pitting corrosion of steel api 5L x42 exposed to solutions containing chloride ions and CO{sub 2} by electrochemical noise measurements; Evaluacion de la susceptibilidad a la corrosion por picado del acero api 5l x42 expuesto a un ambiente con cloruros y CO{sub 2} mediante la tecnica de ruido electroquimico

    Energy Technology Data Exchange (ETDEWEB)

    Pena-Ballesteros, D.; Rodriguez-Vanegas, N.; Anteliz, C.; Sarmiento Klapper, H.

    2011-07-01

    The concentration of chloride ions and the partial pressure of CO{sub 2} play an important role in the degradation of low-carbon steels used for the construction of pipelines in oil and gas industry. In order to evaluate the susceptibility of carbon steel API 5L X42 to pitting corrosion electrochemical noise and linear polarization resistance measurements were carried out in aqueous solutions containing chloride ions and CO{sub 2}. The concentration of chloride ions was varied between, 10000 and 18000 ppm, and the CO{sub 2} partial pressure between 10 psi and 18 psi. Experimental results pointed out that the formation of protective layer, consisting mainly of FeCO{sub 3}, depends on the partial pressure of CO{sub 2} in the system. Nevertheless, the stability of this layer was considerably affected by increasing the concentration of chloride ions causing that localized corrosion has taken place in some areas of the surface of API 5L X42, which were detected by electrochemical noise technique. (Author) 10 refs.

  8. Automatic Potential Titration of Thiocyanate and Chloride Ions in Black Nickel Plating Bath%黑镍镀液中硫氰酸根和氯离子的自动电位滴定

    Institute of Scientific and Technical Information of China (English)

    丘山; 丘星初; 曾家民; 刘星; 刘海燕

    2011-01-01

    The conditions and methods for automatic potential titration of thiocyanate and chloride ions were investigated. The results show that by selecting silver electrode as indication electrode, model 217 Double-liquid connecting electrode as reference electrode, the titration can be continuously operated in nitric acid medium, and these two kinds of ions can also be titrated by steps. When used in analyzing black nickel plating bath, it is easy and fast to operate, and the accuracy and precision can completely meet the demands of production.%研究了用自动电位滴定测定硫氰酸根和氯离子的条件及方法.结果表明:选用银电极为指示电极,217型双液接电极为参比电极,在硝酸介质中既能连续滴定也能分步滴定这两种离子.应用于黑镍镀液分析,方法简便快捷,分析的准确度和精密度完全能满足生产需要.

  9. Chloride ingress prediction

    DEFF Research Database (Denmark)

    Frederiksen, Jens Mejer; Geiker, Mette Rica

    Prediction of chloride ingress into concrete is an important part of durability design of reinforced concrete structures exposed to chloride containing environment. This paper presents the state-of-the art: an analytical model which describes chloride profiles in concrete as function of depth and...... makes physical sense for the design engineer, i.e. the achieved chloride diffusion coefficients at 1 year and 100 years, D1 and D100 respectively, and the corresponding achieved chloride concentrations at the exposed concrete surface, C1 and C100. Data from field exposure supports the assumption of time...... dependent surface chloride concentrations and the diffusion coefficients. Model parameters for Portland cement concretes with and without silica fume and fly ash in marine atmospheric and submerged South Scandinavian environment are suggested in a companion paper based on 10 years field exposure data....

  10. Effect of chloride and sulfate ions in simulated AVT waters on electrochemical corrosion behavior and oxide film characteristics of LP steam turbine materials in power plants

    Energy Technology Data Exchange (ETDEWEB)

    Nakane, Takahiro [Shinshu Univ., Nagano City (Japan). Interdisciplinary Graduate School of Sience and Technology; Goto, Teruyuki [NSK Ltd., Tokyo (Japan); Niu, Li-Bin [Shinshu Univ., Nagano City (Japan). Dept. of Environmental Science and Technology; Takaku, Hiroshi [Shinshu Univ., Nagano City (Japan). Faculty of Engineering

    2010-07-15

    Electrochemical corrosion behavior and film characteristics were investigated in simulated all-volatile treatment (AVT) waters containing both sulfate (SO{sub 4}{sup 2-}) and chloride (Cl{sup -}) for 13Cr, 16Cr-4Ni, 3.5NiCrMoV and high-purity 9CrMoV steels of low-pressure (LP) steam turbines in power plants. Concerning the 13Cr, 16Cr-4Ni and high-purity 9CrMoV steels, the corrosion pit growth proceeded with an increasing content of SO{sub 4}{sup 2-} up to 50 mg x kg{sup -1} in the test water with 100 mg x kg{sup -1} Cl{sup -}, although a SO{sub 4}{sup 2-} concentration above 50 mg x kg{sup -1} in the test water suppressed the corrosion pit growth due to the combined effect of Cl{sup -} and SO{sub 4}{sup 2-}. No corrosion pits occurred for 3.5NiCrMoV steel, which showed predominantly general corrosion in the test waters with Cl{sup -} and SO{sub 4}{sup 2-}. It is concluded that both the heat-treatment-improved 16Cr-4Ni steel for blades and the newly developed high-purity 9CrMoV steel for rotors have a high resistance to pitting corrosion. (orig.)

  11. The effect of chloride ions on the corroded surface layer of 00Cr22Ni5Mo3N duplex stainless steel under cavitation.

    Science.gov (United States)

    Wan, Tong; Xiao, Ning; Shen, Hanjie; Yong, Xingyue

    2016-11-01

    The effects of Cl(-) on the corroded surface layer of 00Cr22Ni5Mo3N duplex stainless steel under cavitation in chloride solutions were investigated using nanoindentation in conjunction with XRD and XPS. The results demonstrate that Cl(-) had a strong effect on the nano-mechanical properties of the corroded surface layer under cavitation, and there was a threshold Cl(-) concentration. Furthermore, a close relationship between the nano-mechanical properties and the cavitation corrosion resistance of 00Cr22Ni5Mo3N duplex stainless steel was observed. The degradation of the nano-mechanical properties of the corroded surface layer was accelerated by the synergistic effect between cavitation erosion and corrosion. A key factor was the adsorption of Cl(-), which caused a preferential dissolution of the ferrous oxides in the passive film layer on the corroded surface layer. Cavitation further promoted the preferential dissolution of the ferrous oxides in the passive film layer. Simultaneously, cavitation accelerated the erosion of the ferrite in the corroded surface layer, resulting in the degradation of the nano-mechanical properties of the corroded surface layer on 00Cr22Ni5Mo3N duplex stainless steel under cavitation. PMID:27245950

  12. Crystal Growth and Spectroscopic characterization of chloride and bromide single crystals doped with rare earth ions for the mid infrared amplification

    International Nuclear Information System (INIS)

    This work is devoted to the study of low phonon energy crystals doped with rare earth ions for the realisation of diode-pumped solid state laser sources emitting in the middle infrared. For that purpose, pure and (Er3+ or Pr3+) doped single crystals of KPb2Cl5 and Tl3PbX5 (X=Cl, Br) have been elaborated by using the Bridgman-Stockbarger method. These non-hygroscopic and congruent melting materials have been found to exhibit phase transitions during the cooling process but which do not limit the elaboration of centimeter-size single crystals. The spectroscopic study of the Er3+ doped compounds has been performed both at high and low temperatures. It thus appears that these systems present long fluorescence lifetimes and relatively large gain cross sections favorable for a laser emission around 4.5μm. It has been demonstrated further that the up-conversion processes resulting from excited-state absorptions of the Er3+ ions around the pumping wavelength as well as the energy transfer processes between the Er3+ ions do not lead to significant optical losses for the laser system. The derived parameters then have been used to build a model and simulate the laser operation of the system following diode pumping around 800 nm. In the end, the spectroscopic study of the Pr3+ ion in various materials has allowed us to evidence large emission cross sections associated with long fluorescence lifetimes, now favorable to a laser emission around 5μm. (author)

  13. Chloride ingress prediction

    DEFF Research Database (Denmark)

    Frederiksen, Jens Mejer; Geiker, Mette Rica

    Prediction of chloride ingress into concrete is an important part of durability design of reinforced concrete structures exposed to chloride containing environment. This paper presents experimentally based design parameters for Portland cement concretes with and without silica fume and fly ash in...... marine atmospheric and submersed South Scandinavian environment. The design parameters are based on sequential measurements of 86 chloride profiles taken over ten years from 13 different types of concrete. The design parameters provide the input for an analytical model for chloride profiles as function...

  14. Electrochemical behaviours of scandium in chloride melts

    International Nuclear Information System (INIS)

    Electrochemical behaviour of scandium(3) ions in an eutectic melt of NaCl-KCl-CsCl at 810-850 K is studied by cyclic voltammetry and chronoamperometry. The process of cathodic reduction of scandium complex ions in chloride melts is found to proceed according to the scheme: Sc(3) → Sc(0) and to be controlled by the rate of ScCl63- complex dissociation

  15. Regulated trafficking of the CFTR chloride channel

    NARCIS (Netherlands)

    Braakman, L.J.; Kleizen, B.; Jonge, H.R. de

    2000-01-01

    The cystic fibrosis transmembrane conductance regulator (CFTR), the ABC transporter encoded by the cystic fibrosis gene, is localized in the apical membrane of epithelial cells where it functions as a cyclic AMP-regulated chloride channel and as a regulator of other ion channels and transporters. Wh

  16. 硫酸蒸煮法去除废糖蜜中氯离子的实验研究%Experimental study on removal of chloride ion in cane molasses by sulfuric acid cooking method

    Institute of Scientific and Technical Information of China (English)

    孟丹; 张海涛

    2013-01-01

    It is a kind of economic and environmental-friendly method that leaching manganese from a low-grade pyrolusite by cane molasses as reducing agent.But a certain amount of chloride ions is found in cane molasses,which will bring serious corrosion damage to the electrolytic anode plate in production practice.Chloride ions were removed from cane molasses and regenerating wastewater by sulfuric acid cooking method.The influences of reaction temperature,reaction time,and concentration of sulfuric acid were investigated.Results showed that using cane molasses treated under the conditions,i.e.mass fraction of H2SO4 was at 40%~45%,reaction time was 2 h,and reaction temperature was 80 ℃,to reduce the pyrolusite,the relative Mn leaching rate was 91.51%,meeting the requirements.%利用废糖蜜作还原剂,还原浸出低品位软锰矿,是一种经济环保的还原方法,但废糖蜜中含有一定的氯离子,在实际生产过程中会对电解阳极板产生严重的腐蚀破坏作用.实验通过硫酸蒸煮法去除废糖蜜和再生废水中的氯离子,考察了反应温度、反应时间和硫酸浓度等因素的影响.实验结果表明,在硫酸质量分数为40%~45%、反应时间为2h、反应温度为80℃的条件下处理废糖蜜还原软锰矿,相对浸出率可达91.51%,符合要求.

  17. Chloride ingress prediction

    DEFF Research Database (Denmark)

    Frederiksen, Jens Mejer; Geiker, Mette Rica

    2008-01-01

    Prediction of chloride ingress into concrete is an important part of durability design of reinforced concrete structures exposed to chloride containing environment. This paper presents experimentally based design parameters for Portland cement concretes with and without silica fume and fly ash in...

  18. Thermogravimetry for optimization of chloride pyro hydrolytic separations in zirconia-magnesia matrix

    International Nuclear Information System (INIS)

    A fast and accurate method for chloride ion determination in zirconia-magnesia matrix was studied the method consists in the pyro hydrolysis of the oxides at 900o C, using a quartz apparatus, during thirty minutes and further determination of the chloride ion collected by means of either ion-selective electrode or ion chromatography. The thermogravimetric curves (TG curves) of the metal oxides and oxychlorides provide all the information about the chloride ion evolution temperature and the influence of pyro hydrolytic accelerators (U3 O8) on ion evolution. (author)

  19. Determination of Anions in High Chloride Matrix by Ion Chromatography with Pre Online Sample Preparation Technique%谱睿在线除氯技术检测高氯水样中的阴离子

    Institute of Scientific and Technical Information of China (English)

    张夕虎; 刘肖

    2011-01-01

    We developed a method in which Dionex "Pre" online sample preparation technique was used to remove chloride by Ag cartridge and Na cartridge. This method is applicable to a wide range of samples and is simpler than offline approach. Each Ag cartridge carries on 400 consecutive injections (25 microlitre each) of 1% NaCl solution, and the removal efficiency is still above 99%. The separation of anions was carried out by high capacity hydroxide selectivity IonPac ASll-HC gradient separation column while Eluent Generator was employed to generate gradient KOH eluent online automatically. Two valves were switched to finish the injection. The system removes chloride well online for different matrix as analysis grade salt and sodium chloride. The detection limits of bromate, chlorate, chlorite, nitrite, nitrate and sulfate are less than 10μg/L, and the recoveries are between 80% and 110%. This method holds the advantages of easy-operation, good reproducibility, lower operation cost etc and is more convenient than off-line approach.%采用戴安公司谱睿(Pre)在线样品前处理技术,使用高容量在线Ag柱和Na柱,开发出了一种柱前去除高氯基体中氯离子的在线分析方法.操作简便,且适用样品范围广;不更换Ag柱可耐受10g/L NaCl基体,25μL连续进样400针,氯离子去除效率可保持在99%以上.系统选用高容量IonPac AS11-HC氢氧根体系阴离子交换色谱柱,在线淋洗液自动发生装置进行梯度淋洗,用抑制型电导检测.对食盐、分析纯氯化钠等不同基体进行检测,可实现样品在线除氯,并可检测其中不高于10μg/L的溴酸根、氯酸根、亚硝酸根、硝酸根和硫酸根等离子.不同离子校准曲线相关系数均在99.8%以上,加标回收率为80%~110%.该技术具有操作简单、可重复性强、方法新颖等特点,解决了以往高氯基体检测成本过高、适用范围有限、前处理操作复杂等问题.

  20. Chloride ingress prediction

    DEFF Research Database (Denmark)

    Frederiksen, Jens Mejer; Geiker, Mette Rica

    2008-01-01

    makes physical sense for the design engineer, i.e. the achieved chloride diffusion coefficients at 1 year and 100 years, D1 and D100 respectively, and the corresponding achieved chloride concentrations at the exposed concrete surface, C1 and C100. Data from field exposure supports the assumption of time...... dependent surface chloride concentrations and the diffusion coefficients. Model parameters for Portland cement concretes with and without silica fume and fly ash in marine atmospheric and submerged South Scandinavian environment are suggested in a companion paper based on 10 years field exposure data....

  1. The role of bicarbonate ions and of adenosine 3',5'-monophosphate (cAMP) in chloride transport by epithelial cells of bullfrog small intestine.

    Science.gov (United States)

    Armstrong, W M; Youmans, S J

    1980-01-01

    In an HCO3-free medium, isolated segments of bullfrog small intestine, stripped of their external muscle layers, displayed a small, serosal positive PD that did not, on the average, differ significantly from zero. Similarly, in this medium, the mean values of Isc and of net Na+ and Cl- absorption under short-circuit conditions did not differ significantly from zero. External HCO3- (25 mM) induced a highly significant serosal negative PD and Isc and a large net absorption of Cl-. Net Cl- absorption exceeded Isc, i.e., there was a significant net flux, JR, which was consistent with a net secretion of HCO3-. The ratio of the internal Cl-activity of the absorptive cells (alpha Cli) to its equilibrium value was larger in the presence than in the absence of HCO3-. In the presence of HCO3-, cAMP, added to the serosal medium, reversed the serosal negative PD and Isc, and inhibited, though it did not completely abolish, net Cl- absorption. JR was unchanged; tissue Cl- and alpha Cli were reduced, and tissue Na+ decreased and tissue K+ increased. When HCO3- and Cl- were removed from the bathing medium, the electrical response of the tissue to cAMP, though greatly attenuated, was not completely abolished. Under these conditions, cAMP induced a significant net Na+ absorption. A model for ion transport in the absorptive cells of the small intestine is proposed that is consistent with these findings. PMID:6249145

  2. The electrochemical behaviour study of La{sup 3+} ion in fused chlorides bath. The LaNi{sub 5} formation; Estudo do comportamento eletroquimico do ion La{sup 3+} em meio a cloretos fundidos. A formacao de LaNi{sub 5}

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Cristiane

    2002-07-01

    The electrochemical behaviour of La{sup 3+} ion was studied in fused chlorides bath, with purpose to obtain LaNi{sub 5} formation parameters. The lanthanum reduction/reoxidation mechanism and intermetallic compound formation were investigated by cyclic voltammetry, chronopotentiommetry and galvanostatic electrodeposition. The electrolyte employed was eutectic mixture NaCl-KCl (1:1) with anhydrous LaCl{sub 3} as solute, since 0,25 mol. L{sup -1} up to 2 mol. L{sup -1}, between 700 deg C and 800 deg C. The anhydrous LaCl{sub 3} was prepared by lanthanum chloride slow dehydration with HCl flow and heating until 300 deg C. Over molybdenum, results depicted that lanthanum electrochemical behaviour was quasi-reversible and electrodeposition occurred in a charge transfer step with three electrons. In nickel, intermetallic compound formation was observed by interdiffusion. The scanning electronic microscopy (SEM-EDS) and X ray diffraction analysis indicated that layers composition depend on temperature and solute concentration in fused bath. Mainly LaNi{sub 5} intermetallic compound was formed with LaCl{sub 3} anhydrous concentration of 2 mol. L{sup -1} at 750 deg C, with cathodic current density until 100 mA.cm{sup -2}. (author)

  3. Hydrogenation of Tasmanian alginite in the presence of tin (II) chloride and zinc chloride

    Energy Technology Data Exchange (ETDEWEB)

    Russell, N.J.

    1981-10-01

    A Mersey River (Tasmanian) algnite concentrate was heated (3 Cmin$SUP$-$SUP$1 to temperatures of 200-480 C in a small capacity, high-pressure, single-cell differential thermal analysis, batch autoclave under nitrogen or hydrogen (initial pressure 9.8 MPa) with or without 10 wt% zinc chloride or tin (II) chloride. An organic solvent (vehicle) was not used in these experiments. Although there is an almost complete conversion of alginite to gaseous and liquid products between 425 and 450 C, the compositions of the autoclave gas samples, the yields and compositions of the hexane-soluble material derived from the autoclave products, and the optical properties of the hexane-soluble residues, reflect the experimental conditions, in particular the influence of the metal chlorides. Principal phases of hydrogen uptake by alginite occur at different temperatures in a hydrogen atmosphere depending on the presence and nature of the metal chloride. The autoclave gas compositions reveal a clear distinction between the uncatalysed and catalysed experiments. The hydrocarbon gas ratios permit a distinction to be made between catalytic (carbonium ion mechanism) reactions and thermal (free radical mechanism) reactions; at higher temperatures the latter are dominant, even in the catalysed experiments. The metal chlorides lower the organic sulphur and nitrogen contents of the hexane-soluble material; zinc chloride being more effective than tin (II) chloride. Incident light fluorescence microscopy suggests that zinc chloride and tin (II) chloride give rise to different hydrogenation reactions between 300 and 425 C. Incident light fluorescence microscopy is a most useful method of studying the petrography of alignite in the hexane-insoluble residues. (28 refs.)

  4. Hydrolysis of ferric chloride in solution

    International Nuclear Information System (INIS)

    The Detox trademark process uses concentrated ferric chloride and small amounts of catalysts to oxidize organic compounds. It is under consideration for oxidizing transuranic organic wastes. Although the solution is reused extensively, at some point it will reach the acceptable limit of radioactivity or maximum solubility of the radioisotopes. This solution could be cemented, but the volume would be increased substantially because of the poor compatibility of chlorides and cement. A process has been developed that recovers the chloride ions as HCl and either minimizes the volume of radioactive waste or permits recycling of the radioactive chlorides. The process involves a two-step hydrolysis at atmospheric pressure, or preferably under a slight vacuum, and relatively low temperature, about 200 degrees C. During the first step of the process, hydrolysis occurs according to the reaction below: FeCl3liquid + H2O → FeOClsolid + 2 HClgas During the second step, the hot, solid, iron oxychloride is sprayed with water or placed in contact with steam, and hydrolysis proceeds to the iron oxide according to the following reaction: 2 FeOClsolid + H2O → Fe2O3solid + 2 HClgas. The iron oxide, which contains radioisotopes, can then be disposed of by cementation or encapsulation. Alternately, these chlorides can be washed off of the solids and can then either be recycled or disposed of in some other way

  5. Chloride equilibrium potential in salamander cones

    Directory of Open Access Journals (Sweden)

    Bryson Eric J

    2004-12-01

    Full Text Available Abstract Background GABAergic inhibition and effects of intracellular chloride ions on calcium channel activity have been proposed to regulate neurotransmission from photoreceptors. To assess the impact of these and other chloride-dependent mechanisms on release from cones, the chloride equilibrium potential (ECl was determined in red-sensitive, large single cones from the tiger salamander retinal slice. Results Whole cell recordings were done using gramicidin perforated patch techniques to maintain endogenous Cl- levels. Membrane potentials were corrected for liquid junction potentials. Cone resting potentials were found to average -46 mV. To measure ECl, we applied long depolarizing steps to activate the calcium-activated chloride current (ICl(Ca and then determined the reversal potential for the current component that was inhibited by the Cl- channel blocker, niflumic acid. With this method, ECl was found to average -46 mV. In a complementary approach, we used a Cl-sensitive dye, MEQ, to measure the Cl- flux produced by depolarization with elevated concentrations of K+. The membrane potentials produced by the various high K+ solutions were measured in separate current clamp experiments. Consistent with electrophysiological experiments, MEQ fluorescence measurements indicated that ECl was below -36 mV. Conclusions The results of this study indicate that ECl is close to the dark resting potential. This will minimize the impact of chloride-dependent presynaptic mechanisms in cone terminals involving GABAa receptors, glutamate transporters and ICl(Ca.

  6. Prediction of the Service Life of a Reinforced Concrete Column under Chloride Environment

    OpenAIRE

    Mohammad K. Alkam; Maha Alqam

    2015-01-01

    In the present investigation, service life of a reinforced concrete column exposed to chloride environment has been predicted. This study has been based on numerical simulation of chloride ion diffusion in a concrete column during its anticipated life span. The simulation process has included the concrete cover replacement whenever chloride ion concentration has reached the critical threshold value at the reinforcement surface. Repair scheduling of the concrete column under consideration has ...

  7. Determination of chloride diffusion constants for concretes of differing water to cement ratios and admixtures

    OpenAIRE

    Smith, David Gilman

    1988-01-01

    Reinforced concrete exposed to chlorides is subject to rapid deterioration once the concentration of the chloride ion in the concrete reaches a critical level to cause corrosion of the reinforcing steel. The chloride ion diffuses through concrete according to Fick's Law, which is a function of time, a driving concentration, and a diffusion constant. The diffusion constant varies with temperature and the variety of concrete . The research included determination of diffusion ...

  8. Response to comments on "Local impermeant anions establish the neuronal chloride concentration"

    DEFF Research Database (Denmark)

    Glykys, J; Dzhala, V; Egawa, K; Balena, T; Saponjian, Y; Kuchibhotla, K V; Bacskai, B J; Kahle, K T; Zeuthen, T; Staley, K J

    2014-01-01

    We appreciate the interest in our paper and the opportunity to clarify theoretical and technical aspects describing the influence of Donnan equilibria on neuronal chloride ion (Cl(-)) distributions.......We appreciate the interest in our paper and the opportunity to clarify theoretical and technical aspects describing the influence of Donnan equilibria on neuronal chloride ion (Cl(-)) distributions....

  9. Method for the Determination of Chloride Ion Flux with the Automatic Potentiometric Titration%自动电位滴定法测定焊剂中氯离子的方法

    Institute of Scientific and Technical Information of China (English)

    朵云琨; 邓勇; 朵云峰

    2014-01-01

    采用自动电位滴定法测定焊剂中氯离子的质量分数,对试样的处理、酸度的影响、线性范围、标准回收、精密度和准确度等进行探究.结果表明:对样品11次测定值的相对标准偏差(RSD)为2.27%~2.35%,标准回收率为99.00%~100.80%;所用方法的准确度和精密度较好,适合于焊剂中0.02%~1.00%氯离子的测定.%Using Auto-electric titration method measured Cl-in flux of mass fraction,the sample processing,the effects of acidity,linear range,standard recovery,precision and accuracy were studied.The results show that:the relative standard deviation of the measured val-ue of the samples for eleven times (RSD)ranged from 2.27%-2.35%;the standard recovery rate was 99.0%-100.8%;The accuracy and precision of the method are good,and suitable for the determination of 0.02%-1.00%in the flux of chloride ion.

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

    Science.gov (United States)

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

    2016-06-01

    Vitreous fluid can be used to analyze sodium and chloride levels in deceased persons, but it remains unclear to what extent such results can be used to diagnose antemortem sodium or chloride imbalances. In this study we present vitreous sodium and chloride levels from more than 3000 cases. We show that vitreous sodium and chloride levels both decrease with approximately 2.2mmol/L per day after death. Since potassium is a well-established marker for postmortem interval (PMI) and easily can be analyzed along with sodium and chloride, we have correlated sodium and chloride levels with the potassium levels and present postmortem reference ranges relative the potassium levels. We found that virtually all cases outside the reference range show signs of antemortem hypo- or hypernatremia. Vitreous sodium or chloride levels can be the only means to diagnose cases of water or salt intoxication, beer potomania or dehydration. We further show that postmortem vitreous sodium and chloride strongly correlate and in practice can be used interchangeably if analysis of one of the ions fails. It has been suggested that vitreous sodium and chloride levels can be used to diagnose drowning or to distinguish saltwater from freshwater drowning. Our results show that in cases of freshwater drowning, vitreous sodium levels are decreased, but that this mainly is an effect of postmortem diffusion between the eye and surrounding water rather than due to the drowning process, since the decrease in sodium levels correlates with immersion time. PMID:27105154

  11. Catalytic Conversion of Cellulose to Levulinic Acid by Metal Chlorides

    Directory of Open Access Journals (Sweden)

    Beixiao Zhang

    2010-08-01

    Full Text Available The catalytic performance of various metal chlorides in the conversion of cellulose to levulinic acid in liquid water at high temperatures was investigated. The effects of reaction parameters on the yield of levulinic acid were also explored. The results showed that alkali and alkaline earth metal chlorides were not effective in conversion of cellulose, while transition metal chlorides, especially CrCl3, FeCl3 and CuCl2 and a group IIIA metal chloride (AlCl3, exhibited high catalytic activity. The catalytic performance was correlated with the acidity of the reaction system due to the addition of the metal chlorides, but more dependent on the type of metal chloride. Among those metal chlorides, chromium chloride was found to be exceptionally effective for the conversion of cellulose to levulinic acid, affording an optimum yield of 67 mol % after a reaction time of 180 min, at 200 °C, with a catalyst dosage of 0.02 M and substrate concentration of 50 wt %. Chromium metal, most of which was present in its oxide form in the solid sample and only a small part in solution as Cr3+ ion, can be easily separated from the resulting product mixture and recycled. Finally, a plausible reaction scheme for the chromium chloride catalyzed conversion of cellulose in water was proposed.

  12. 上海市域地下水环境氯离子含量的时空演化特征研究%Study on the Temporal and Spatial Evolution Characteristics of Chloride Ion Content in the Groundwater Environment of Shanghai City

    Institute of Scientific and Technical Information of China (English)

    王玉强

    2015-01-01

    There is a wide distribution of Chloride Ion in groundwater, so it is of great significance to probe into the temporal and spatial dynamic evolution of Chloride content in groundwater environment. The results showed there existed a relevantly great change in the annual content of Chloride Ion in the groundwater of Shanghai City, presenting a regular quadric curve or cubic curve. Furthermore, the change in each aquifer presented a significant difference. From the perspective of its vertical distribution, the average content of Chloride Ion from height to lowness in turn was the second confined aquifer , the fifth confined aquifer, the unconfined aquifer, the fourth and the third confined aquifer.%鉴于氯离子在地下水中的分布很广,因此,探究地下水环境氯离子含量时空动态演化规律具有重要意义。研究发现,上海市地下水环境 Cl-含量年际演化幅度比较大,且呈现规律性的二次曲线或三次曲线,各个含水层之间的变化呈显著性差异。从其垂直方向分布看,氯离子平均含量由高到低依次为第二承压含水层,第五承压含水层,潜水含水层,第四承压含水层和第三承压含水层。

  13. (tert-Butyl(2-hydroxyethylammonium chloride

    Directory of Open Access Journals (Sweden)

    Cintya Valerio-Cárdenas

    2014-07-01

    Full Text Available In the cation of the title molecular salt, C6H16NO+·Cl−, the N—C—C—O torsion angle is 176.5 (2°. In the crystal, the cations and chloride ions are linked by N—H...O and O—H...O hydrogen bonds, generating a two-dimensional network parallel to (100.

  14. Determination of the constants of the solubility product of Ln(OH)3 and the effect of the chloride ions on the lanthanum hydrolysis, praseodymium and lutetium in aqueous solutions of ion force 2 Molar

    International Nuclear Information System (INIS)

    The behavior of lanthanum (III), praseodymium (III), and lutetium (III) was studied in 2 M NaClO4 (aq) and 2 M NaCl (aq) at 303 K and free -CO2 conditions. Solubility diagrams (p Ln(aq)-pCH) were obtained by means of a radiochemical method. The pCH borderlines of saturation and unsaturation zones of the solutions and solubility product constants for Ln(OH)3 were determined from these diagrams. The fitting of the solubility equation to the experimental values of p Ln(aq)-pCH diagrams allowed the calculation of the first hydrolysis and solubility product constants. Independently, the stability constants for the first species of hydrolysis were determined by means of pH titrations, the data were treated with the program SUPERQUAD and fitted to the mean ligand number equation. The stability constants for the species LnCl2+ were as well calculated in 2M ionic strength and 303 K from the hydrolysis constant values obtained in both perchlorate and chloride media. The values obtained for La, Pr and Lu were: logKps: 21.11 ± 0.09, 19.81 ± 0.11 and 18.10 ± 0.13 in 2M NaClO4; logKps: 22.22 ± 0.09, 21.45 ± 0.14 and 18.52 ± 0.29 in 2M NaCl; log β1: - 8.64 ± 0.02, - 8.37 ± 0.01 and - 7.95 ± 0.11 in 2M NaClO4; log β1/ : - 9.02 ± 0.11, - 8.75 ± 0.01 and - 8.12 ± 0.03 in 2M NaCl and the values for log β1,Cl were - 0.0255, - 0.155 and - 0.758, respectively. (Author)

  15. Interactions between chloride and cement-paste materials.

    Science.gov (United States)

    Barberon, Fabien; Baroghel-Bouny, Véronique; Zanni, Hélène; Bresson, Bruno; d'Espinose de la Caillerie, Jean-Baptiste; Malosse, Lucie; Gan, Zehong

    2005-02-01

    The durability of cement-based materials with respect to exterior aggressions is one of the current priorities in civil engineering. Depending on their use, the cement-based materials can be exposed to different types of aggressive environments. For instance, damages to concrete structures in contact with a saline environment (sea water on bridges, deicing salts on roads, etc.) are of utmost importance. Upon exposure to saline water, Cl- ions penetrate into the structures and subsequently lead to reinforcement corrosion. Chloride attack is often combined with other aggressive influences such as temperature (e.g., freezing) or the ingress of other ions (e.g., sulfates in sea water). We therefore aim to explore the effect of sodium chloride (NaCl) on the structural chemistry of cement paste. Existing studies about reinforcement corrosion by chloride have focused on the penetration of Cl- ions and the comparison between "free" ions (water-soluble ions) and bound ones. However, little is known about the fixation mechanisms, the localization of Cl in the cement matrix and the structural interaction between Cl and the silicate and aluminate hydrate phases present in cement paste. We present here results of a multinuclear nuclear magnetic resonance study on the fixation of chloride in the hydration products and the characterization of new phases potentially appearing due to chloride ingress. PMID:15833625

  16. Chloride removal from vitrification offgas

    International Nuclear Information System (INIS)

    This study identified and investigated techniques of selectively purging chlorides from the low-level waste (LLW) vitrification process with the purge stream acceptable for burial on the Hanford Site. Chlorides will be present in high concentration in several individual feeds to the LLW Vitrification Plant. The chlorides are highly volatile in combustion type melters and are readily absorbed by wet scrubbing of the melter offgas. The Tank Waste Remediation System (TWRS) process flow sheets show that the resulting chloride rich scrub solution is recycled back to the melter. The chlorides must be purged from the recycle loop to prevent the buildup of excessively high chloride concentrations

  17. Durability Analysis of Subway Station in Chloride Environment

    OpenAIRE

    Yang LuFeng; Yu Bo; Hong Bin

    2013-01-01

    In this study, a finite element model for chloride ions transport in saturated concrete was proposed based on the Fick’s second law of diffusion. The governing partial differential equation was solved numerically in space as a boundary-value problem and in time as an initial-value problem by means of the finite element formulations. The maximum allowable value of chloride diffusion coefficient within different locations of subway station with service life of 100a was achieved and suggestions ...

  18. cis-Dichloridobis(1,10-phenanthrolinechromium(III chloride

    Directory of Open Access Journals (Sweden)

    Xiaoli Gao

    2011-02-01

    Full Text Available In the title complex, [CrCl2(C12H8N22]Cl, the CrIII ion is situated on a twofold rotation axis and displays a slightly distorted octahedral CrCl2N4 coordination geometry. The Cr environment is composed of a cis arrangement of two 1,10-phenanthroline and two chloride ligands. The chloride counter-anion exhibits half-occupation and is equally disordered over two positions.

  19. The Study on Detection of Chloride Ion in Flue Gas Ammonium Sulfate Slurry by Automatic Potentiometric Titration Method%自动电位滴定法测定烟气氨法脱硫模拟浆液中氯离子的研究

    Institute of Scientific and Technical Information of China (English)

    杭蕾; 吕程; 陈慧慧; 连洲洋; 袁礼锐; 魏无际

    2015-01-01

    Chloride ion content of ammonia desulfurization process is an important monitoring indicators and this paper dis-cusses the detection of chloride ions in ammonium sulfate slurry by automatic potentiometric titration .The results show that :adding ethanol helps to increase the magnitude of the potential jump ;when pH=3-5 ,the result is accurate ;the recovery rate keeps between 90% and 110% ;compared with the Mohr method ,the test result is more accurate and precise and free from ash color;also the tested result is close to ion chromatography detection result ,but the high concentrations of chloride ion potentiometric titration is more advantageous .%氯离子含量是氨法脱硫工艺中的一个重要监控指标,用自动电位滴定法测定氨法脱硫浆液中的氯离子。结果表明,实验加入乙醇有利于增大电位突跃幅度;pH值为3~5时实验结果准确;加标回收率为90%~110%;与莫尔法相比,测定结果准确度、精密度更高,且不受灰分颜色干扰;与离子色谱法测定结果准确度、精密度相近,但测定高浓度氯离子电位滴定法更有优势。

  20. Durability Analysis of Subway Station in Chloride Environment

    Directory of Open Access Journals (Sweden)

    Yang LuFeng

    2013-02-01

    Full Text Available In this study, a finite element model for chloride ions transport in saturated concrete was proposed based on the Fick’s second law of diffusion. The governing partial differential equation was solved numerically in space as a boundary-value problem and in time as an initial-value problem by means of the finite element formulations. The maximum allowable value of chloride diffusion coefficient within different locations of subway station with service life of 100a was achieved and suggestions for durability analysis of subway station in chloride environment were also proposed.

  1. Relationship between chloride diffusivity and pore structure of hardened cement paste

    Institute of Scientific and Technical Information of China (English)

    Guo-wen SUN; Wei SUN; Yun-sheng ZHANG; Zhi-yong LIU

    2011-01-01

    Based on effective media theory, a predictive model, relating chloride diffusivity to the capillary pores, gel pores,tortuosity factor, and pore size distribution of hardened cement, is proposed. To verify the proposed model, the diffusion coefficient of chloride ions, the degree of hydration, and peak radius of capillary pores of cement paste specimens were measured. The predicted results for chloride diffusivity were compared with published data. The results showed that the predicted chloride diffusivity of hardened cement paste was in good agreement with the experimental results. The effect of the evolution of pore structures in cement paste on chloride diffusivity could be deduced simultaneously using the proposed model.

  2. Structural and mechanistic studies of chloride induced activation of human pancreatic α-amylase

    OpenAIRE

    Maurus, Robert; Begum, Anjuman; Kuo, Hsin-Hen; Racaza, Andrew; Numao, Shin; Andersen, Carsten; Tams, Jeppe W.; Vind, Jesper; Overall, Christopher M.; Withers, Stephen G.; Brayer, Gary D

    2005-01-01

    The mechanism of allosteric activation of α-amylase by chloride has been studied through structural and kinetic experiments focusing on the chloride-dependent N298S variant of human pancreatic α-amylase (HPA) and a chloride-independent TAKA-amylase. Kinetic analysis of the HPA variant clearly demonstrates the pronounced activating effect of chloride ion binding on reaction rates and its effect on the pH-dependence of catalysis. Structural alterations observed in the N298S variant upon chlorid...

  3. Cyanuric chloride reagent as a chloride ion donor: synthesis, crystal structure, and magnetic properties of [Cu.sub.2./sub.(2-APM).sub.2./sub.(μ-Cl).sub.2./sub.(μ-OCH.sub.3./sub.).sub.2./sub.].sub.n./sub. coordination polymer

    Czech Academy of Sciences Publication Activity Database

    Hosseini-Monfared, H.; Mojtabazadeh, F.; Bikas, R.; Eigner, Václav; Dušek, Michal; Gutiérrez, A.

    2014-01-01

    Roč. 67, č. 21 (2014), s. 3510-3518. ISSN 0095-8972 R&D Projects: GA ČR(CZ) GA14-03276S Institutional support: RVO:68378271 Keywords : copper(II) coordination polymer * in situ reaction * cyanuric chloride * structure * magnetic study Subject RIV: CA - Inorganic Chemistry Impact factor: 2.012, year: 2014

  4. [Degradation of succinylcholine chloride].

    Science.gov (United States)

    Németh, G; Török, I; Paál, T

    1993-05-01

    Quantitative thin-layer chormatographic method has been developed for the investigation of the degradation of injection formulations containing succinylcholinium chloride. The method is based on the denistometric determination of the main degradation product, choline at 430 nm after visualization with iodine vapour. The stability of the injection was investigated under various storage conditions and it has been stated that considerable decomposition takes place during as short a period as one week. PMID:8362654

  5. An experiment on multibubble sonoluminescence spectra in sodium chloride solution

    Institute of Scientific and Technical Information of China (English)

    CHEN Zhan; XU JunFeng; HUANG Wei; CHEN WeiZhong; MIAO GuoQing

    2008-01-01

    We investigated experimentally the spectra of MBSL in sodium chloride water solution with krypton as dissolved gas. We observed and compared the spectra of hydroxyl ion at 310 nm and that of sodium atom at 589 nm. It has been found that under the same experimental condition, the intensity of sodium atom spectra is obviously higher than that of the hydroxyl ion spectra, and is more sensitive to the experimental condition. The krypton content, the concentration of sodium chloride solution, and the driving sound pressure obviously affect the spectra intensity in certain range.

  6. Dynamic [Cl{sup -}]{sub i} measurement with chloride sensing quantum dots nanosensor in epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang Yuchi; Mao Hua; Wong, Lid B, E-mail: ywang@biotechplex.com [BioTechPlex Corporation, 1205 Linda Vista Drive Suite A, San Marcos, CA 92078 (United States); Cytoptics Corporation, 1205 Linda Vista Drive Suite B, San Marcos, CA 92078 (United States)

    2010-02-05

    We have synthesized a chloride sensing quantum dots (QD) nanosensor, Cl-QD, for the dynamic measurements of chloride ion concentration in the millimolar range, a sensitivity that is applicable to most physiological intracellular chloride ion concentration ([Cl{sup -}]{sub i}) measurements in epithelial cells. The Cl-QD is synthesized by conjugating an anion receptor, 1-(2-mercapto-ethyl)-3-phenyl-thiourea (MEPTU) to a water soluble CdSe/ZnS QD at an emission wavelength of 620 nm. Upon binding of chloride ions to the Cl-QD, a photo-induced electron transfer mechanism caused the fluorescence of the QD to quench. This resulted in an inversely proportional relationship between the chloride ion concentration and the fluorescence intensity of the Cl-QD. We have utilized this Cl-QD to measure [Cl{sup -}]{sub i} in T84 and CF-PAC cultured cells, with either the C1C-2 or CFTR chloride channels being manipulated by pharmacological chloride channel activators and inhibitors. Activations of C1C-2 and CFTR chloride channels in T84 by the respective lubiprostone and genistein caused predictive increases in the fluorescence of the Cl-QD, i.e., a decrease of [Cl{sup -}]{sub i}. Conversely, glibenclamide, a chloride channel inhibitor, applied to the CF-PAC cells caused a predictable decrease in the fluorescence of Cl-QD due to the increase of [Cl{sup -}]{sub i}. These are the first data in using QD-based chloride ion sensors for dynamic measurements of intracellular chloride ion concentrations in epithelial cells.

  7. Hydrolysis of ferric chloride in solution

    Energy Technology Data Exchange (ETDEWEB)

    Lussiez, G.; Beckstead, L.

    1996-11-01

    The Detox{trademark} process uses concentrated ferric chloride and small amounts of catalysts to oxidize organic compounds. It is under consideration for oxidizing transuranic organic wastes. Although the solution is reused extensively, at some point it will reach the acceptable limit of radioactivity or maximum solubility of the radioisotopes. This solution could be cemented, but the volume would be increased substantially because of the poor compatibility of chlorides and cement. A process has been developed that recovers the chloride ions as HCl and either minimizes the volume of radioactive waste or permits recycling of the radioactive chlorides. The process involves a two-step hydrolysis at atmospheric pressure, or preferably under a slight vacuum, and relatively low temperature, about 200{degrees}C. During the first step of the process, hydrolysis occurs according to the reaction below: FeCl{sub 3 liquid} + H{sub 2}O {r_arrow} FeOCl{sub solid} + 2 HCl{sub gas} During the second step, the hot, solid, iron oxychloride is sprayed with water or placed in contact with steam, and hydrolysis proceeds to the iron oxide according to the following reaction: 2 FeOCl{sub solid} + H{sub 2}O {r_arrow} Fe{sub 2}O{sub 3 solid} + 2 HCl{sub gas}. The iron oxide, which contains radioisotopes, can then be disposed of by cementation or encapsulation. Alternately, these chlorides can be washed off of the solids and can then either be recycled or disposed of in some other way.

  8. Mechanisms of chloride decomposition in upgrading oil sands bitumen

    Energy Technology Data Exchange (ETDEWEB)

    Le, T.; Diaz, D.; Gray, M. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering; Eaton, P. [Champion Technologies, Fresno, TX (United States); Wu, A. [Syncrude Canada Ltd., Edmonton, AB (Canada). Edmonton Research Centre

    2004-07-01

    In addition to clay minerals, bitumens from mining operations contain chloride salts because of the salinity of the extraction process water and the connate water in the ore. These chlorides form corrosive hydrochloric acid. High concentrations of organic acid components known as naphthenic acids are also found in bitumen from Alberta's oil sands. These also cause corrosion. Chloride salts, clays and organic acids may interact in the presence of steam to promote hydrochloric acid formation causing major corrosion problems in downstream facilities. This study examined the behaviour of these components under upgrading conditions. In particular, it examined the rate and the extent of the hydrolysis reactions for salts found in bitumen. Mixtures of bitumen, salts and organic acids were exposed to flowing steam at 100 to 400 degrees C under nitrogen purge. Ion chromatography was used to analyze the condensed vapours for chloride.

  9. Ion Channels, Natural Nanovalves

    OpenAIRE

    Eisenberg, Bob

    2012-01-01

    Ion channels are proteins with holes down their middle that control the flow of ions and electric current across otherwise impermeable biological membranes. The flow of sodium, potassium, calcium (divalent), and chloride ions have been central issues in biology for more than a century. The flow of current is responsible for the signals of the nervous system that propagate over long distances (meters). The concentration of divalent calcium ions is a 'universal' signal that controls many differ...

  10. 自动电位滴定法测定工业铬酸酐中氯离子含量方法研究%The Research Method to Determine Chloride Ion Content in Chromium Trioxide for Industrial Use with Automatic Potentiometric Titration

    Institute of Scientific and Technical Information of China (English)

    胡清启; 孙宁

    2015-01-01

    用乙醇作还原剂,将铬酸酐中CrO42-还原为Cr3+,再用硝酸银标准溶液滴定,以电位变化率最大点确定反应终点,求出氯离子含量。就精密度和加标回收进行实验,并对方法展开分析与讨论,该方法的建立对工业生产铬酸酐中氯离子指标的控制具有指导意义。%Reduce the CrO42+to Cr3+in chromium trioxide with ethanol as the reductant ,then determine the content of chloride ion using AgNO3 standard solution to titrate to the end point that has a biggest change of potential. Conduct an experiment for calculating the precision and standard addition recovery of the method,and then analysis and discuss about the method.This method has a guiding significance for controlling the content of chloride ion in the industrial production of chromium trioxide.

  11. Electrochemical activity of heavy metal oxides in the process of chloride induced corrosion of steel reinforcement

    Indian Academy of Sciences (India)

    V Živica

    2002-10-01

    The influence of heavy metal oxides on the chloride induced corrosion of steel reinforcement in concrete was studied. Significant inhibition and stimulation of chloride induced corrosion have been observed. Basicity and acidity of the relevant metal ions, and their ability to form complexes are considered as the main factors of the observed effects.

  12. 不同养护条件下低水胶比混凝土抗氯离子渗透性及孔结构试验研究%Study of the resistance to chloride ions penetration and pore structure of concrete with low water-binder ratio under various curing conditions

    Institute of Scientific and Technical Information of China (English)

    段运; 王起才; 张戎令; 谢超

    2016-01-01

    为研究不同养护条件对低水胶比混凝土抗氯离子渗透性和孔结构的影响规律及程度,采用气孔分析法、压汞法和RCM法、电通量法对不同养护条件下低水胶比混凝土28 d孔结构和抗氯离子渗透性进行测试。试验结果表明:负温(-3℃)和低温(3℃)养护条件下,低水胶比混凝土比其标准养护条件下孔径明显粗化,大孔数量增多,小孔数量减少,气孔间距系数和气孔平均直径增大;低水胶比混凝土中多害孔和有害孔数量、临界孔径和最可几孔径明显比其标准养护条件下大,且负温养护条件下增大程度更大;低水胶比混凝土28 d电通量和氯离子迁移系数明显大于其标准养护条件下的混凝土,抗氯离子渗透性能明显降低;负温养护条件下,混凝土抗氯离子渗透性能下降程度很大,主要是由于负温不仅使孔的连通性增强、孔径粗化和劣化,而且对混凝土内部孔结构造成了一定程度的不可恢复的损伤。%In order to study the influencing mechanism of various curing conditions on the resistance to chloride i-ons penetration and pore structure of concrete with low water-binder ratio,porosity analysis,mercury injection method,Electric flux method and RCMmethod were adopted in the study.These methods were used in the experi-ment to test the pore structure and the resistance to chloride ions penetration of the low water-binder ratio concrete after curing 28d.The result shows that the aperture of concrete with low water-binder ratio after being cured un-der minus temperature (-3℃)and low temperature (3℃)is obviously roughened than is cured under standard conditions.The number of larger aperture increases,while the number of smaller apertures decreases.The bubbles spacing factor and average pore size increase.The number of more harmful holes,the critical aperture and maxi-mum probability aperture in concrete with low water

  13. Reaction of uranium dioxide with copper-containing chloride melts

    International Nuclear Information System (INIS)

    Cermet composition materials consisting of metallic copper and uranium dioxide can be used for manufacturing fuel rods of nuclear power reactors. Reprocessing of such irradiated fuel of dispersive type can be done employing non-aqueous pyrochemical methods and developing such technology requires information on interaction of uranium dioxide with chloride melts containing copper ions

  14. Mass-spectrometric investigation of thermochemical properties of lanthanide chlorides

    Energy Technology Data Exchange (ETDEWEB)

    Sapegin, A.M.; Baluev, A.V.; Evdokimov, V.I. (AN SSSR, Chernogolovka. Inst. Novykh Khimicheskikh Problem)

    1984-12-01

    Ionization potentials are measured for ions formed during lanthanide chloride molecules ionization by an electron shock with the use of the improved technique of mass-spectral data processing. Energies of atomization and atomic bond scission in molecules of tri-, di-, and monochlorides are defined along with enthalpies of formation of these molecules in a gaseous state.

  15. Mass-spectrometric investigation of thermochemical properties of lanthanide chlorides

    International Nuclear Information System (INIS)

    Ionization potentials are measured for ions formed during lanthanide chloride molecules ionization by an electron shock with the use of the improved technique of mass-spectral data processing. Energies of atomization and atomic bond scission in molecules of tri-, di-, and monochlorides are defined along with enthalpies of formation of these molecules in a gaseous state

  16. (tert-Butyl)(2-hydroxyethyl)ammonium chloride

    OpenAIRE

    Cintya Valerio-Cárdenas; Simón Hernández-Ortega; David Morales-Morales

    2014-01-01

    In the cation of the title molecular salt, C6H16NO+·Cl−, the N—C—C—O torsion angle is 176.5 (2)°. In the crystal, the cations and chloride ions are linked by N—H...O and O—H...O hydrogen bonds, generating a two-dimensional network parallel to (100).

  17. Boldine action against the stannous chloride effect.

    Science.gov (United States)

    Reiniger, I W; Ribeiro da Silva, C; Felzenszwalb, I; de Mattos, J C; de Oliveira, J F; da Silva Dantas, F J; Bezerra, R J; Caldeira-de-Araújo, A; Bernardo-Filho, M

    1999-12-15

    Peumus boldus extract has been used in popular medicine in the treatment of biliar litiase, hepatic insufficiency and liver congestion. Its effects are associated to the substance boldine that is present in its extract. In the present work, we evaluated the influence of boldine both in: (i) the structural conformation of a plasmid pUC 9.1 through gel electrophoresis analysis; and in (ii) the survival of the strain of Escherichia coli AB1157 submitted to reactive oxygen species (ROS), generated by a Fenton like reaction, induced by stannous chloride. Our results show a reduction of the lethal effect induced by stannous chloride on the survival of the E. coli culture in the presence of boldine. The supercoiled form of the plasmid is not modified by stannous chloride in the presence of boldine. We suggest that the protection induced by boldine could be explained by its anti-oxidant mechanism. In this way, the boldine could be reacting with stannous ions, protecting them against the oxidation and, consequently, avoiding the generation of ROS. PMID:10624900

  18. Solubility of sodium chloride in superheated steam

    International Nuclear Information System (INIS)

    The solubility of sodium chloride in superheated steam was investigated in laboratory-scale experiments up to 20 MPa and 475 C. These experiments were carried out using a dynamic method where deionized steam was passed through a packed bed of salt crystals in a 500 mL Hastelloy autoclave. The residence time of the steam in the salt bed was sufficient to saturate the steam with the salt. The steam samples were cooled and analyzed by ion chromatography. Correlations based on temperature and density were selected to describe the solubility of sodium chloride in superheated steam. The density dependence is much stronger than the temperature dependence. By using these correlations, it is possible to estimate the solubility of salt in steam at lower densities than those used in the experiments. Enthalpy-entropy diagrams are given that show the steam expansion line in turbines, including curves for constant concentration of sodium chloride solubility in steam. These can be used to analyze where in the steam cycle this salt may deposit. (orig.)

  19. Extraction of copper(II) and zinc(II) from chloride media with mixed extractants

    International Nuclear Information System (INIS)

    Extraction of copper(II) and zinc(II) from acidic chloride solutions with mixtures of two extractants: a basic or solvating one and a chelating extractant was discussed. Processes for recovery and separation of Cu(II) from Zn(II) were proposed, which consist of the following steps: extraction from chloride media with the formation of metal chlorocomplex ion pair or solvate, scrubbing of chloride ions with an aqueous solution of appropriate pH with simultaneous transfer of the metal ion to the chelate, traditional stripping with sulphuric acid and conditioning of the basic extractant. Both effective recovery and separation of metal ions with simultaneous change of the system from the chloride to the sulphate state can be achieved. A bifunctional reagent, such as alkyl derivative of 8-hydroxyquinoline, can be also used instead of the extractant mixture. (author)

  20. Extractant of copper(II) and zinc(II) from chloride media with mixed extractants

    International Nuclear Information System (INIS)

    Extraction of copper(II) and zinc(II) from acidic chloride solutions with mixtures of two extractants: a basic or solvating one and a chelating extractant was discussed. The processes for recovery and separation of Cu(II) from Zn(II) were proposed. The processes consist of the following steps: extraction from chloride media with the formation of metal chloro-complex ion pair or solvate, scrubbing of chloride ions with an aqueous solution of appropriate pH with simultaneous transfer of the metal ion to the chelate, traditional stripping with sulphuric acid and conditioning of the basic extractant. Both effective recovery and separation of metal ions with simultaneous change of the system from the chloride to sulphate one can be achieved. A bifunctional reagent, such as alkyl-derivative of 8-hydroxyquinoline, can be also used instead of the extractant mixture. (authors)

  1. Valyl benzyl ester chloride

    Directory of Open Access Journals (Sweden)

    Grzegorz Dutkiewicz

    2010-02-01

    Full Text Available In the title compound (systematic name: 1-benzyloxy-3-methyl-1-oxobutan-2-aminium chloride, C12H18NO2+·Cl−, the ester group is approximately planar, with a maximum deviation of 0.040 (2 Å from the least-squares plane, and makes a dihedral angle of 28.92 (16° with the phenyl ring. The crystal structure is organized by N—H...Cl hydrogen bonds which join the two components into a chain along the b axis. Pairs of chains arranged antiparallel are interconnected by further N—H...Cl hydrogen bonds, forming eight-membered rings. Similar packing modes have been observed in a number of amino acid ester halides with a short unit-cell parameter of ca 5.5 Å along the direction in which the chains run.

  2. Influence of Fly Ash on Surface Chloride Concentration Under Shallow Immersion Condition

    OpenAIRE

    Liu, Jun; Wang, Xiaodong; Xing, Feng; Han, Ningxu

    2014-01-01

    In this paper, the influence of fly ash content on concrete surface chloride concentration was investigated through periodical tests of surface chloride concentration of concrete by immersing three kinds of concrete specimens in 5.0 wt.% sodium chloride solution. One kind of specimen is common concrete without fly ash, whereas the other two kinds of specimens are mixed with fly ash. The results show that the surface chloride ion concentration ranges from 0.295 to 0.777 wt.% for the immersed c...

  3. Indium sulfide precipitation from hydrochloric acid solutions of calcium and sodium chlorides

    International Nuclear Information System (INIS)

    The effect of precipitation duration, acid concentration, indium complexing with chloride ions on the process of indium sulfide chemical precipitation in hydrochloric acid solutions, precipitate composition and dispersity are studied. It is established that indium sulfide solubility increases in solutions with acid concentration exceeding 0.40-0.45 mol/l. Calcium and indium chloride addition to diluted hydrochloric solutions greatly increases the solubility of indium sulfide. The effect of calcium chloride on In2S3 solubility is higher than that of sodium chloride

  4. A molecular dynamics study of chloride binding by the cryptand SC24

    Science.gov (United States)

    Owenson, B.; MacElroy, R. D.; Pohorille, A.

    1988-01-01

    The capture of chloride from water by the tetraprotonated form of the spherical macrotricyclic molecule SC24 was studied using molecular dynamics simulation methods. This model ionophore represents a broad class of molecules which remove ions from water. Two binding sites for the chloride were found, one inside and one outside the ligand. These sites are separated by a potential energy barrier of approximately 20 kcal mol-1. The major contribution to this barrier comes from dehydration of the chloride. The large, unfavorable dehydration effect is compensated for by an increase in electrostatic attraction between the oppositely charged chloride and cryptand, and by energetically favorable rearrangements of water structure. Additional assistance in crossing the barrier and completing the dehydration of the ion is provided by the shift of three positively charged hydrogen atoms of the cryptand towards the chloride. This structural rigidity is partially responsible for its selectivity.

  5. Prediction of chloride ingress and binding in cement paste

    DEFF Research Database (Denmark)

    Geiker, Mette Rica; Nielsen, Erik Pram; Herforth, Duncan

    2007-01-01

    Portland cement pastes at any content of chloride, alkalis, sulfates and carbonate was verified experimentally and found to be equally valid when applied to other data in the literature. The thermodynamic model for predicting the phase equilibria in hydrated Portland cement was introduced into an existing...... Finite Difference Model for the ingress of chlorides into concrete which takes into account its multi-component nature. The “composite theory” was then used to predict the diffusivity of each ion based on the phase assemblage present in the hydrated Portland cement paste. Agreement was found between...... steady state diffusion however. It simply implies that incremental increases in the concentration of diffusing ions in the pore solution will rapidly re-equilibrate with the hydrates present locally, where, the greater the ratio of bound to free ions, the greater the buffering effect which slows down the...

  6. Photonic crystal fiber based chloride chemical sensors for corrosion monitoring

    Science.gov (United States)

    Wei, Heming; Tao, Chuanyi; Krishnaswamy, Sridhar

    2016-04-01

    Corrosion of steel is one of the most important durability issues in reinforced concrete (RC) structures because aggressive ions such as chloride ions permeate concrete and corrode steel, consequently accelerating the destruction of structures, especially in marine environments. There are many practical methods for corrosion monitoring in RC structures, mostly focusing on electrochemical-based sensors for monitoring the chloride ion which is thought as one of the most important factors resulting in steel corrosion. In this work, we report a fiber-optic chloride chemical sensor based on long period gratings inscribed in a photonic crystal fiber (PCF) with a chloride sensitive thin film. Numerical simulation is performed to determine the characteristics and resonance spectral response versus the refractive indices of the analyte solution flowing through into the holes in the PCF. The effective refractive index of the cladding mode of the LPGs changes with variations of the analyte solution concentration, resulting in a shift of the resonance wavelength, hence providing the sensor signal. This fiber-optic chemical sensor has a fast response, is easy to prepare and is not susceptible to electromagnetic environment, and can therefore be of use for structural health monitoring of RC structures subjected to such aggressive environments.

  7. Chemical characterization of a potassium hydroxyapatite prepared by soaking in potassium chloride and carbonate solutions.

    Science.gov (United States)

    Nordström, E G; Karlsson, K H

    1992-01-01

    A potassium-doped synthetic apatite was prepared by soaking hydroxyapatite in potassium carbonate and potassium chloride solutions. The hydroxyapatite was prepared by firing slip cast ceramic bodies in vacuum at 1100 degrees C. The conical ceramic samples and a crushed material of this were soaked in carbonate and chloride solutions for 2, 4, 6, and 8 weeks. Potassium, calcium, and phosphate were determined by direct current plasma emission spectroscopy. The carbonate content was determined by thermogravimetric analysis and chloride titrimetrically. After 2 weeks, one potassium ion substituted one calcium ion when soaked in a carbonate solution. When soaked in the chloride solution substitution occurred to the same extent. At phosphate sites the substitution of phosphate for carbonate occurred at one sixth of the sites after 2 weeks. Chloride incorporated one half of the OH-sites after 2 weeks. After 4 weeks about one chloride ion was found in the apatite, and after 6 weeks one and a half of the OH-sites were occupied by chloride ions. PMID:1483120

  8. Sodium chloride, potassium chloride, and virulence in Listeria monocytogenes.

    OpenAIRE

    MYERS, E. R.; Dallmier, A W; Martin, S E

    1993-01-01

    Virulence, as determined in a mouse model, and the virulence factor activities of catalase, superoxide dismutase, and listeriolysin O were examined in a parental strain (10403S) and in a nonhemolytic mutant strain (DP-L224) of Listeria monocytogenes. The cells were propagated in media containing various concentrations of sodium chloride or potassium chloride. Strains 10403S and DP-L224 exhibited significant increases in catalase activity and listeriolysin O activity when grown in medium conta...

  9. The need of alkalinity determination in the characterization of rain; Necesidad de la determinacion de la alcalinidad en la caracterizacion de la lluvia

    Energy Technology Data Exchange (ETDEWEB)

    Pal Verma, Mahendra [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1998-01-01

    In this paper is presented the alkalinity determination of the carbonic species in the rain waters by the Gran titration method. The alkalinity values obtained by this method in low electric conductivity waters are fairly reliable. Also, the existing studies on the characterization of acid rains, are discussed. [Espanol] En este trabajo se presenta la medicion de la alcalinidad y la determinacion de las especies carbonicas en las aguas de lluvia por el metodo de la titulacion de Gran. Los valores de alcalinidad obtenidos por este metodo en las aguas de baja conductividad electrica son bastante confiables. Asimismo, se discuten los estudios existentes sobre la caracterizacion de la lluvia acida en la republica mexicana.

  10. Chloride channels in stroke

    Institute of Scientific and Technical Information of China (English)

    Ya-ping ZHANG; Hao ZHANG; Dayue Darrel DUAN

    2013-01-01

    Vascular remodeling of cerebral arterioles,including proliferation,migration,and apoptosis of vascular smooth muscle cells (VSMCs),is the major cause of changes in the cross-sectional area and diameter of the arteries and sudden interruption of blood flow or hemorrhage in the brain,ie,stroke.Accumulating evidence strongly supports an important role for chloride (Clˉ) channels in vascular remodeling and stroke.At least three Clˉ channel genes are expressed in VSMCs:1) the TMEM16A (or Ano1),which may encode the calcium-activated Clˉ channels (CACCs); 2) the CLC-3 Clˉ channel and Clˉ/H+ antiporter,which is closely related to the volume-regulated Clˉ channels (VRCCs); and 3) the cystic fibrosis transmembrane conductance regulator (CFTR),which encodes the PKA-and PKC-activated Clˉ channels.Activation of the CACCs by agonist-induced increase in intracellular Ca2+ causes membrane depolarization,vasoconstriction,and inhibition of VSMC proliferation.Activation of VRCCs by cell volume increase or membrane stretch promotes the production of reactive oxygen species,induces proliferation and inhibits apoptosis of VSMCs.Activation of CFTR inhibits oxidative stress and may prevent the development of hypertension.In addition,Clˉ current mediated by gammaaminobutyric acid (GABA) receptor has also been implicated a role in ischemic neuron death.This review focuses on the functional roles of Clˉ channels in the development of stroke and provides a perspective on the future directions for research and the potential to develop Clˉ channels as new targets for the prevention and treatment of stroke.

  11. Adsorption of Tetradecylpyridinium Chloride on Aqueous Surfaces of Sodium Chloride Solutions

    OpenAIRE

    Fujio, Katsuhiko; Hayashi, Koji; Suzuki, Maki

    2014-01-01

    Surface tension of aqueous NaCl solutions of tetradecylpyridinium chloride (TPC) has been measured by the drop weight method at different NaCl concentrations from 0 to 1.000 mol dm−3 at 25◦C. Surface excess densities of tetradecylpyridinium ion (TP+), Cl− and Na+ have been obtained as functions of TPC concentration at different NaCl concentrations by applying the Gibbs adsorption isotherm to the surface tension data below the critical micelle concentration (CMC) of TPC. Surface excess densiti...

  12. Adsorption of Dodecylpyridinium Chloride on Aqueous Surfaces of Sodium Chloride Solutions

    OpenAIRE

    Fujio, Katsuhiko; TAKEUCHI, Kumiko; Suzuki, Maki

    2012-01-01

    Surface tension of aqueous NaCl solutions of dodecylpyridinium chloride (DPC) has been measured by the drop weight method at different NaCl concentrations from 0 to 1.000 mol dm-3 at 25℃. Applying the Gibbs adsorption isotherm to the surface tension data at DPC concentrations below the critical micelle concentration (CMC), surface excess densities of dodecylpyridinium ion (DP+), Cl- and Na+ have been obtained as functions of DPC concentration at different NaCl concentrations. Surface excess d...

  13. A synthetic chloride channel restores chloride conductance in human cystic fibrosis epithelial cells.

    Directory of Open Access Journals (Sweden)

    Bing Shen

    Full Text Available Mutations in the gene-encoding cystic fibrosis transmembrane conductance regulator (CFTR cause defective transepithelial transport of chloride (Cl(- ions and fluid, thereby becoming responsible for the onset of cystic fibrosis (CF. One strategy to reduce the pathophysiology associated with CF is to increase Cl(- transport through alternative pathways. In this paper, we demonstrate that a small synthetic molecule which forms Cl(- channels to mediate Cl(- transport across lipid bilayer membranes is capable of restoring Cl(- permeability in human CF epithelial cells; as a result, it has the potential to become a lead compound for the treatment of human diseases associated with Cl(- channel dysfunction.

  14. Monoclonal Antibodies to the Apical Chloride Channel in Necturus Gallbladder Inhibit the Chloride Conductance

    Science.gov (United States)

    Finn, Arthur L.; Tsai, Lih-Min; Falk, Ronald J.

    1989-10-01

    Monoclonal antibodies raised by injecting Necturus gallbladder cells into mice were tested for their ability to inhibit the apical chloride conductance induced by elevation of cellular cAMP. Five of these monoclonal antibodies bound to the apical cells, as shown by indirect immunofluorescence microscopy, and inhibited the chloride conductance; one antibody that bound only to subepithelial smooth muscle, by indirect immunofluorescence microscopy, showed no inhibition of chloride transport. The channel or a closely related molecule is present in the membrane whether or not the pathway is open, since, in addition to inhibiting the conductance of the open channel, the antibody also bound to the membrane in the resting state and prevented subsequent opening of the channel. The antibody was shown to recognize, by ELISA, epitopes from the Necturus gallbladder and small intestine. Finally, by Western blot analysis of Necturus gallbladder homogenates, the antibody was shown to recognize two protein bands of Mr 219,000 and Mr 69,000. This antibody should permit isolation and characterization of this important ion channel.

  15. Chloride binding regulates the Schiff base pK in gecko P521 cone-type visual pigment.

    Science.gov (United States)

    Yuan, C; Kuwata, O; Liang, J; Misra, S; Balashov, S P; Ebrey, T G

    1999-04-01

    The binding of chloride is known to shift the absorption spectrum of most long-wavelength-absorbing cone-type visual pigments roughly 30 nm to the red. We determined that the chloride binding constant for this color shift in the gecko P521 visual pigment is 0.4 mM at pH 6.0. We found an additional effect of chloride on the P521 pigment: the apparent pKa of the Schiff base in P521 is greatly increased as the chloride concentration is increased. The apparent Schiff base pKa shifts from 8.4 for the chloride-free form to >10.4 for the chloride-bound form. We show that this shift is due to chloride binding to the pigment, not to the screening of the membrane surface charges by chloride ions. We also found that at high pH, the absorption maximum of the chloride-free pigment shifts from 495 to 475 nm. We suggest that the chloride-dependent shift of the apparent Schiff base pKa is due to the deprotonation of a residue in the chloride binding site with a pKa of ca. 8.5, roughly that of the Schiff base in the absence of chloride. The deprotonation of this site results in the formation of the 475 nm pigment and a 100-fold decrease in the pigment's ability to bind chloride. Increasing the concentration of chloride results in the stabilization of the protonated state of this residue in the chloride binding site and thus increased chloride binding with an accompanying increase in the Schiff base pK. PMID:10194387

  16. Influence of water hardness and sulfate on the acute toxicity of chloride to sensitive freshwater invertebrates.

    Science.gov (United States)

    Soucek, David J; Linton, Tyler K; Tarr, Christopher D; Dickinson, Amy; Wickramanayake, Nilesh; Delos, Charles G; Cruz, Luis A

    2011-04-01

    Total dissolved solids (TDS) represent the sum of all common ions (e.g., Na, K, Ca, Mg, chloride, sulfate, and bicarbonate) in freshwater. Currently, no federal water quality criteria exist for the protection of aquatic life for TDS, but because the constituents that constitute TDS are variable, the development of aquatic life criteria for specific ions is more practical than development of aquatic life criteria for TDS. Chloride is one such ion for which aquatic life criteria exist; however, the current aquatic life criteria dataset for chloride is more than 20 years old. Therefore, additional toxicity tests were conducted in the current study to confirm the acute toxicity of chloride to several potentially sensitive invertebrates: water flea (Ceriodaphnia dubia), fingernail clams (Sphaerium simile and Musculium transversum), snail (Gyraulus parvus), and worm (Tubifex tubifex), and determine the extent to which hardness and sulfate modify chloride toxicity. The results indicated a significant ameliorating effect of water hardness (calcium and magnesium) on chloride toxicity for all species tested except the snail; for example, the 48-h chloride median lethal concentration (LC50) for C. dubia at 50 mg/L hardness (977 mg Cl(-) /L) was half that at 800 mg/L hardness (1,836 mg Cl(-) /L). Conversely, sulfate over the range of 25 to 600 mg/L exerted a negligible effect on chloride toxicity to C. dubia. Rank order of LC50 values for chloride at a given water hardness was in the order (lowest to highest): S. simile tubifex. Results of the current study support the contention that the specific conductivity or TDS concentration of a water body alone is not a sufficient predictor of acute toxicity and that knowledge of the specific ion composition is critical. PMID:21191883

  17. Crystal structure of Halobacterium salinarum halorhodopsin with a partially depopulated primary chloride-binding site.

    Science.gov (United States)

    Schreiner, Madeleine; Schlesinger, Ramona; Heberle, Joachim; Niemann, Hartmut H

    2016-09-01

    The transmembrane pump halorhodopsin in halophilic archaea translocates chloride ions from the extracellular to the cytoplasmic side upon illumination. In the ground state a tightly bound chloride ion occupies the primary chloride-binding site (CBS I) close to the protonated Schiff base that links the retinal chromophore to the protein. The light-triggered trans-cis isomerization of retinal causes structural changes in the protein associated with movement of the chloride ion. In reverse, chemical depletion of CBS I in Natronomonas pharaonis halorhodopsin (NpHR) through deprotonation of the Schiff base results in conformational changes of the protein: a state thought to mimic late stages of the photocycle. Here, crystals of Halobacterium salinarum halorhodopsin (HsHR) were soaked at high pH to provoke deprotonation of the Schiff base and loss of chloride. The crystals changed colour from purple to yellow and the occupancy of CBS I was reduced from 1 to about 0.5. In contrast to NpHR, this chloride depletion did not cause substantial conformational changes in the protein. Nevertheless, two observations indicate that chloride depletion could eventually result in structural changes similar to those found in NpHR. Firstly, the partially chloride-depleted form of HsHR has increased normalized B factors in the region of helix C that is close to CBS I and changes its conformation in NpHR. Secondly, prolonged soaking of HsHR crystals at high pH resulted in loss of diffraction. In conclusion, the conformation of the chloride-free protein may not be compatible with this crystal form of HsHR despite a packing arrangement that hardly restrains helices E and F that presumably move during ion transport. PMID:27599860

  18. Influence of sulphates on chloride diffusion and the effect of this on service life prediction of concrete in a submerged marine environment

    OpenAIRE

    Maes, M; Caspeele, R.; Van den Heede, P.; De Belie, N.

    2012-01-01

    Single-ion attack by chlorides and multi-ion attack by chlorides and sulphates were compared with respect to the full probabilistic service life prediction of concrete structures, according to fib Bulletin 34. Especially the influence of sulphates on the chloride diffusion coefficient was investigated more thoroughly. Four concrete mixtures were tested, two Portland cement concretes and two blast-furnace slag concretes. Migration tests and natural diffusion tests were executed, based on NT bu...

  19. N,N-Dimethyldehydroabietylammonium chloride ethanol monosolvate

    Directory of Open Access Journals (Sweden)

    Xiu-Zhi Huang

    2013-06-01

    Full Text Available The title compound {systematic name: 1-[(1R,4aS,10aR-7-isopropyl-1,4a-dimethyl-1,2,3,4,4a,9,10,10a-octahydrophenanthren-1-yl]-N,N-dimethylmethanaminium chloride ethanol monosolvate}, C22H36N+·Cl−·C2H6O, was synthesized from dehydroabietylamine by N-methylation with formaldehyde/formic acid and transformation into the hydrochloride. The dehydroabietyl moiety exhibits the usual conformation with the two cyclohexane rings in chair and half-chair conformations and a trans-ring junction. The crystal structure is built up from columns of the dehydroabietyl moieties stacked along the a axis. These columns are held together by the chloride ions via N—H...Cl and C—H...Cl interactions, which establish a two-dimensional network parallel to (010. The ethanol solvent molecules are located between the columns and anchored via O—H...Cl hydrogen bonds.

  20. The electrodeposition of lead from chloride electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Wright, A.

    1986-11-28

    At low current densities, lead was deposited onto a lead substrate as a fine powder that did not adhere well to the substrate. At higher current densities dendritic growth occurred. Lead does not adhere to a graphite substrate and, since copper and titanium substrates require higher cell voltages than lead substrates, these three substrates were rejected. The temperature of the electrolyte must be maintained above 69/sup 0/C to avoid the precipitation of lead chloride in the cell. Optimum current efficiencies at the anode and cathode were obtained at 80/sup 0/C, and no improvement in the morphology of the deposit was observed at higher temperatures. A combination of Quebracho extract and cuprous ions achieved the greatest improvement in the morphology of the deposit, while maintaining high current efficiencies at the anode and cathode. However, when the deposition time was increased, dendritic growth was much in evidence. A compact, adherent deposit of lead could not be obtained from chloride electrolytes. 22 refs., 21 figs., 11 tabs.

  1. Raman and DFT Study on N-H+…Cl- Hydrogen Bonding in 1,1,3,3-Tetra-Methylguanidinium Chloride forming an Ion-pair Molecule in the Vapor Phase

    DEFF Research Database (Denmark)

    Berg, Rolf W.; Riisager, Anders; Fehrmann, Rasmus

    gaseous free states without any assumed symmetry. The calculations on the monomeric [TMGH]+ ion and the dimeric ion pair converged to give geometries near the established crystal structure of the [TMGH]Cl salt. This salt is known to contain dimeric ion pairs of the kind [TMGH]ClCl[TMGH](Fig.1......).Experimentally obtained Raman scattering spectra of the compound (as the solid, as solutes in ethanolic and aqueous solutions and as a vapor at 225 ºC) are presented and assigned, by comparing to the ab initio vibrational analyses (calculated IR and Raman band positions and intensities). It is concluded that...... dimeric molecular ion pairs with four N-H+…Cl- hydrogen bonds seem to exist also in the solutions, and probably are responsible for the relatively high solubility of the “salt” in ethanol. The “salt” can be easily sublimed at about 200-230 oC. The Raman spectrum of the vapor at 225 ºC has a characteristic...

  2. Aspects of the magnetism of ferrous chloride

    International Nuclear Information System (INIS)

    This work is a critical review of the existing work on ferrous chloride and presents, as well, a number of new experimental results. First, a careful analysis of the level structure of ferrous ions in the crystalline field shows that the crystalline anisotropy is of the same order of magnitude as the exchange interactions, a feature which gives rise to some particular effects, such as an upward curvature of the magnetization curve at 0 K in a perpendicular magnetic field. Further, the very low temperature (T > 0.4 K) thermal variation of both the specific heat and magnetic susceptibility evidences a magnetic component in elementary excitations. This result suggests the presence of a large magneto-elastic coupling. Finally, an experimental study of the H-T phase diagram near TN and of the critical behaviour of the specific heat and parallel susceptibility was performed. (author)

  3. Synthesis, spectroscopic and thermal studies of the copper(II) aspartame chloride complex

    Science.gov (United States)

    Çakır, S.; Coşkun, E.; Naumov, P.; Biçer, E.; Bulut, İ.; İçbudak, H.; Çakır, O.

    2002-08-01

    Aspartame adduct of copper(II) chloride Cu(Asp) 2Cl 2·2H 2O (Asp=aspartame) is synthesized and characterized by elemental analysis, FT IR, UV/vis, ESR spectroscopies, TG, DTG, DTA measurements and molecular mechanics calculations. Aqueous solution of the green solid absorbs strongly at 774 and 367 nm. According to the FT IR spectra, the aspartame moiety coordinates to the copper(II) ion via its carboxylate ends, whereas the ammonium terminal groups give rise to hydrogen bonding network with the water, the chloride ions or neighboring carboxylate groups. The results suggest tetragonally distorted octahedral environment of the copper ions.

  4. Swell activated chloride channel function in human neutrophils

    Energy Technology Data Exchange (ETDEWEB)

    Salmon, Michael D. [Leukocyte and Ion Channel Research Laboratory, School of Health and Biosciences, University of East London, Stratford Campus, London E15 4LZ (United Kingdom); Ahluwalia, Jatinder, E-mail: j.ahluwalia@uel.ac.uk [Leukocyte and Ion Channel Research Laboratory, School of Health and Biosciences, University of East London, Stratford Campus, London E15 4LZ (United Kingdom)

    2009-04-17

    Non-excitable cells such as neutrophil granulocytes are the archetypal inflammatory immune cell involved in critical functions of the innate immune system. The electron current generated (I{sub e}) by the neutrophil NADPH oxidase is electrogenic and rapidly depolarises the membrane potential. For continuous function of the NADPH oxidase, I{sub e} has to be balanced to preserve electroneutrality, if not; sufficient depolarisation would prevent electrons from leaving the cell and neutrophil function would be abrogated. Subsequently, the depolarisation generated by the neutrophil NADPH oxidase I{sub e} must be counteracted by ion transport. The finding that depolarisation required counter-ions to compensate electron transport was followed by the observation that chloride channels activated by swell can counteract the NADPH oxidase membrane depolarisation. In this mini review, we discuss the research findings that revealed the essential role of swell activated chloride channels in human neutrophil function.

  5. Estimating the chloride transport in cement paste

    Directory of Open Access Journals (Sweden)

    Princigallo, A.

    2012-06-01

    Full Text Available A method was developed to measure the diffusion coefficient of chloride ions in cement paste based on an analytical solution to Fick’s 2nd law in a cylindrical coordinate system. This natural method yielded diffusivity results within as little as a month. Testing time was reduced by exploiting the three-dimensional inward flux in the specimen. In an attempt to determine the saturation concentration, dense portland cement pastes were exposed to a concentrated chloride solution. The method proved to be useful for exploring cement hydration-induced changes in the diffusion coefficient of cement paste.

    Se ha desarrollado un método para medir el coeficiente de difusión de los iones cloruro en la pasta de cemento, partiendo de una aplicación analítica de la segunda ley de Fick en un sistema de coordinadas cilíndrico. Este método, que es natural, demostró ser capaz de producir resultados de difusividad en tan solo un mes. Se consiguió reducir el tiempo de ensayo mediante el aprovechamiento de la tridimensionalidad del flujo desde el exterior al interior de la probeta. A fin de determinar la concentración de saturación, se sometieron las pastas de cemento Portland a una disolución de cloruros concentrada. Este método resultó ser útil en el estudio de los cambios del coeficiente de difusión de la pasta de cemento provocados por las reacciones de hidratación que tienen lugar en esta.

  6. Δ1-Pyrroline-5-carboxylate reductase from Arabidopsis thaliana: stimulation or inhibition by chloride ions and feedback regulation by proline depend on whether NADPH or NADH acts as co-substrate.

    Science.gov (United States)

    Giberti, Samuele; Funck, Dietmar; Forlani, Giuseppe

    2014-05-01

    Δ(1)-pyrroline-5-carboxylate (P5C) reductase (P5CR) catalyses the final step of proline synthesis in plants. In Arabidopsis thaliana, protein levels are correlated neither to the corresponding mRNA copy numbers, nor to intracellular proline concentrations. The occurrence of post-translational regulatory mechanisms has therefore been hypothesized, but never assessed. The purification of A. thaliana P5CR was achieved through either a six-step protocol from cultured cells, or heterologous expression of AtP5CR in Escherichia coli. The protein was characterized with respect to structural, kinetic, and biochemical properties. P5CR was able to use either NADPH or NADH as the electron donor, with contrasting affinities and maximum reaction rates. The presence of equimolar concentrations of NADP(+) completely suppressed the NADH-dependent activity, whereas the NADPH-dependent reaction was mildly affected. Proline inhibited only the NADH-dependent reaction. At physiological values, increasing concentrations of salt progressively inhibited the NADH-dependent activity, but were stimulatory of the NADPH-dependent reaction. The biochemical properties of A. thaliana P5CR suggest a complex regulation of enzyme activity by the redox status of the pyridine nucleotide pools, and the concentrations of proline and chloride in the cytosol. Data support a to date underestimated role of P5CR in controlling stress-induced proline accumulation. PMID:24467670

  7. Stability of succinylcholine chloride injection.

    Science.gov (United States)

    Schmutz, C W; Mühlebach, S F

    1991-03-01

    The stability of succinylcholine chloride injection prepared by a hospital pharmacy was studied under a wide variety of conditions. Batches of succinylcholine chloride injection 10 mg/mL containing sodium chloride, methyl-4-hydroxybenzoate, hydrochloric acid, and water were prepared. Samples were tested for the effect of initial pH (3.0 and 4.2) and sterilization (steam treatment at 100 degrees C for 30 minutes and 121 degrees C for 20 minutes) on stability after three weeks; long-term stability under refrigeration (12, 17, and 23 months of storage at 4 degrees C); and the effect of storage temperature (4-6 degrees C, 20-26 degrees C, 35 degrees C, and 70 degrees C) and light exposure at various intervals up to 12 months. Samples were analyzed by thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). Unlike heating at 121 degrees C, heating at 100 degrees C produced no significant loss of succinylcholine chloride, independent of the initial pH. Succinylcholine chloride was hydrolyzed only minimally over 23 months if the solution was stored at 4-6 degrees C. A 10% loss of drug content occurred if solutions were kept at 20-26 degrees C for five months, at 35 degrees C for one month, or at 70 degrees C for one day. Initial degradation was slowed if the solution was protected from light. The assessments by TLC proved to be more sensitive than the HPLC measurements. Succinylcholine chloride injection sterilized at 100 degrees C for 30 minutes can be stored for up to five months at room temperature if protected from light. The preparation is stable for at least two years under refrigeration. PMID:2028996

  8. Effect of NGBFS and CBA as fine aggregate on the chloride permeability of concrete

    Directory of Open Access Journals (Sweden)

    İsa Yüksel

    2013-09-01

    Full Text Available This paper presents the results of an investigation which was about influence of non-ground Coal Bottom Ash (CBA and Non-Ground Granulated Blast-Furnace Slag (NGBFS as fine aggregate on rapid chloride permeability of concrete. Series of Rapid Chloride Permeability Test (RCPT were conducted with concrete specimens containing NGBFS and CBA in varying percentages from 10 to 50% with the step of 10% of fine aggregate by weight. Two basic series concrete specimens were prepared in laboratory. The first series (G was contained NGBFS, the second series (B was contained CBA as fine aggregate. Test results indicated that NGBFS or CBA improves the resistance to chloride ion penetration tosome extent. 30% and 10% replacement ratios were selected as optimum replacement ratios for G and B series. It was concluded that GBFS was more impressive then CBA for blocking chloride ion movements.

  9. Durability of Steel Fibres Reinforcement Concrete Beams in Chloride Environment Combined with Inhibitor

    Directory of Open Access Journals (Sweden)

    AbdelMonem Masmoudi

    2016-01-01

    Full Text Available This paper presented the effect of the combination of an inhibitor and steel fibre reinforced concrete (SFRC for concrete structures in chloride environments. Twelve beams were cast and tested to study their flexural behavior. The morphology of steel surfaces using the inhibitor after observing the scanning electron microscope showed a low layer of corrosion products. The steel surface immersed in the inhibitor free solution was seen to have been subject to chloride ions attacks as shown in this study. The interest to the field of the present study is the relatively higher durability of the performance when using the inhibitor. Crack width and crack spacing for beams under the same load showed that the use of SFRC with the inhibitor for concrete structures in chloride environments must have transferred tension across cracks that led to reducing crack spacing without any chloride ions attack.

  10. Diffusion of chloride and uranium in compacted sodium bentonite

    International Nuclear Information System (INIS)

    The authors discuss the measurement of sorption and diffusion of chloride (Cl-36) and uranium in compacted sodium bentonite MX-80. No sorption was observed in the sorption tests, however, in the diffusion tests slight sorption of uranium was noticed. The diffusivities of Cl-36 were found to be strongly dependent on the compaction of bentonite and on the salt concentration of the solution. Ion-exclusion can propably explain these phenomena. The diffusivities of uranium were also strongly dependent on the compaction of bentonite. Uranium shows features of both ion-exclusion and sorption

  11. The effect of pulse current on energy saving during Electrochemical Chloride Extraction (ECE) in concrete

    DEFF Research Database (Denmark)

    Sun, Tian R.; Geiker, Mette R.; Ottosen, Lisbeth M.

    Energy consumption is a factor influencing the cost of Electrochemical Chloride Extraction (ECE) in concrete. The aims of this work were to investigate the possibility for energy saving when using a pulsed electric field during ECE and the effect of the pulsed current on removal of chloride. Four......+ ions from the anodic reaction entering the concrete, and the pulse current also demonstrated a positive effect on the energy consumption across the membrane by diminishing the concentration polarization....

  12. cis-Dichloridobis(1,10-phenanthroline)chromium(III) chloride

    OpenAIRE

    Xiaoli Gao

    2011-01-01

    In the title complex, [CrCl2(C12H8N2)2]Cl, the CrIII ion is situated on a twofold rotation axis and displays a slightly distorted octahedral CrCl2N4 coordination geometry. The Cr environment is composed of a cis arrangement of two 1,10-phenanthroline and two chloride ligands. The chloride counter-anion exhibits half-occupation and is equally disordered over two positions.

  13. Corrosion of Steel in Concrete and Its Prevention in Aggressive Chloride-Bearing Environments

    OpenAIRE

    Bertolini, Luca; Carsana, Maddalena; Gastaldi, Matteo; Lollini, Federica; Redaelli, Elena

    2016-01-01

    This keynote paper deals with the durability of reinforced concrete (RC) structures exposed to aggressive environments characterized by high concentration of chloride ions, namely, marine environments or the use of de-icing salts. The mechanism of chloride-induced corrosion of steel in concrete is introduced, and its influence on the service life of RC structures is analyzed. Factors affecting the time to corrosion initiation are described with regard to both concrete properties and environme...

  14. Effect of Chloride Content on Bond Behavior Between FRP and Concrete

    Institute of Scientific and Technical Information of China (English)

    潘金龙; 黄毅方; 邢锋

    2010-01-01

    For reinforced concrete structures located along the seaside, the penetration of chloride ions into concrete may be a threat to the durability of the structures. Experimental investigations were carried out to study the effect of chloride content on the bond behavior between concrete and fiber reinforced polymer (FRP) plates. Direct shear tests were conducted on the FRP strengthened concrete members. Before testing, the specimens were immersed in NaCl solutions with concentrations ranging from 3%—15% for di...

  15. Crevice corrosion of alloy 22 in fluoride and chloride containing solutions

    International Nuclear Information System (INIS)

    Alloy 22 (N06022) is highly resistant to localized corrosion. Alloy 22 may be susceptible to crevice corrosion in pure chloride (Cl-) solutions under aggressive environmental conditions. The effect of the fluoride (F-) on the susceptibility to crevice corrosion induced by chloride ions is still not well established. The objective of the present work was to explore the crevice corrosion resistance of this alloy to different mixtures of fluorides and chlorides. Cyclic potentiodynamic polarization (CPP) tests were conducted in deaerated aqueous solutions of pure halide ions and also in different mixtures of chloride and fluoride at 90 C degrees and pH 6. The range of chloride concentration [Cl-] was 0.001 M ≤ [Cl-] ≤ 1 M and the range of molar fluoride to chloride ratio [F-]/[Cl-] was 0.1≤ [F-]/[Cl-] ≤ 10. Results showed that Alloy 22 was susceptible to crevice corrosion in all the pure chloride solutions but not in the pure fluoride solutions. A molar ratio [F-]/[Cl-] ranging from 5 to 10 was required for the inhibition of crevice corrosion to be complete in the halide mixtures. A moderate or nil inhibitive effect was observed for molar ratios [F-]/[Cl-] < 5. (author)

  16. Development of chloride attack prediction model for concrete structure of NPP

    International Nuclear Information System (INIS)

    Material properties and structural performance of Nuclear Power Plant structures subjected to physical and environmental factors, degrade during life time due to continuous deterioration such as rebar corrosion and concrete cracking. In special NPP structures are exposed to chloride environment since they are located in seashore area. In this study, a chloride attack prediction model is developed to predict corrosion initiation of reinforcing bars in NPP structures, based on governing equations that take into account the diffusion of chloride ions and a mechanical steady state. It can offer information which is used to determine an optimal time for repair and rehabilitation actions of the structure

  17. 1,5-Diaminotetrazolium chloride

    Directory of Open Access Journals (Sweden)

    Ling-Qiao Meng

    2010-04-01

    Full Text Available The title compound, CH5N6+·Cl−, crystallized with two indepedent 1,5-diaminotetrazolium cations and two independent chloride anions in the asymmetric unit. In the crystal, there are a number of N—H...Cl hydrogen-bonding interactions, which generate a three-dimensional network.

  18. 活性粉末混凝土微观结构及其对强度与抗氯离子渗透性能的影响研究%Influence of micro-structure on the strength and resistance to chloride ion permeability of reactive powder concrete

    Institute of Scientific and Technical Information of China (English)

    余自若; 高康; 安明喆; 韩松

    2013-01-01

    The samples of reactive powder concrete mixed with various mineral admixtures were prepared and tested to investigate the strength and electric flux. The hydration products, pore-structure and micro-structure were studied by X-ray diffraction (XRD), mercury intrusion porosimetry (MIP) and scanning electron microscope (SEM). The high strength and resistance to chloride ion permeability mechanism of RPC was discussed. The results indicated that the content of silica fume is the most important factor to enhance the performance of reactive powder concrete. The porosities of samples incorporated with mineral powder and metakaolin are lower than those samples which contain silica fume only. As cured with high temperature, metakaolin is more powerful in improving the resistance to chloride ion permeability than mineral powder. With the increasing of curing temperature, the strength and resistance to permeability are increased obviously, and this character is not influenced by the changing of mineral raw materials blending method.%在多种矿物掺合料混掺的活性粉末混凝土的强度和电通量试验基础上,运用x射线衍射分析(XRD)、汞压力测孔分析(MIP)及扫描电镜观察(SEM)技术,研究了活性粉末混凝土的主要水化产物、孔结构和微观形貌,探讨了各种矿物掺合料对活性粉末混凝土的强度和抗氯离子渗透性的影响机理.研究结果表明,在各种活性粉末对混凝土的性能增强作用中,硅粉的含量是最主要的因素;掺入矿粉和偏高岭土的活性粉末混凝土样品,比单一使用硅粉的样品孔隙率略低;高温养护下偏高岭土在提高材料抗氯离子渗透性方面的作用比矿粉明显;不论对于哪一种矿物原料的掺合方式,活性粉末混凝土的强度和抗氯离子渗透性能都随着养护温度的提高而有所增强.

  19. Suppression of adenosine-activated chloride transport by ethanol in airway epithelia.

    Directory of Open Access Journals (Sweden)

    Sammeta V Raju

    Full Text Available Alcohol abuse is associated with increased lung infections. Molecular understanding of the underlying mechanisms is not complete. Airway epithelial ion transport regulates the homeostasis of airway surface liquid, essential for airway mucosal immunity and lung host defense. Here, air-liquid interface cultures of Calu-3 epithelial cells were basolaterally exposed to physiologically relevant concentrations of ethanol (0, 25, 50 and 100 mM for 24 hours and adenosine-stimulated ion transport was measured by Ussing chamber. The ethanol exposure reduced the epithelial short-circuit currents (I(SC in a dose-dependent manner. The ion currents activated by adenosine were chloride conductance mediated by cystic fibrosis transmembrane conductance regulator (CFTR, a cAMP-activated chloride channel. Alloxazine, a specific inhibitor for A(2B adenosine receptor (A(2BAR, largely abolished the adenosine-stimulated chloride transport, suggesting that A(2BAR is a major receptor responsible for regulating the chloride transport of the cells. Ethanol significantly reduced intracellular cAMP production upon adenosine stimulation. Moreover, ethanol-suppression of the chloride secretion was able to be restored by cAMP analogs or by inhibitors to block cAMP degradation. These results imply that ethanol exposure dysregulates CFTR-mediated chloride transport in airways by suppression of adenosine-A(2BAR-cAMP signaling pathway, which might contribute to alcohol-associated lung infections.

  20. Simultaneous optical recording in multiple cells by digital holographic microscopy of chloride current associated to activation of the ligand-gated chloride channel GABA(A receptor.

    Directory of Open Access Journals (Sweden)

    Pascal Jourdain

    Full Text Available Chloride channels represent a group of targets for major clinical indications. However, molecular screening for chloride channel modulators has proven to be difficult and time-consuming as approaches essentially rely on the use of fluorescent dyes or invasive patch-clamp techniques which do not lend themselves to the screening of large sets of compounds. To address this problem, we have developed a non-invasive optical method, based on digital holographic microcopy (DHM, allowing monitoring of ion channel activity without using any electrode or fluorescent dye. To illustrate this approach, GABA(A mediated chloride currents have been monitored with DHM. Practically, we show that DHM can non-invasively provide the quantitative determination of transmembrane chloride fluxes mediated by the activation of chloride channels associated with GABA(A receptors. Indeed through an original algorithm, chloride currents elicited by application of appropriate agonists of the GABA(A receptor can be derived from the quantitative phase signal recorded with DHM. Finally, chloride currents can be determined and pharmacologically characterized non-invasively simultaneously on a large cellular sampling by DHM.

  1. Chloride content and pH value in the pore solution of concrete under carbonation

    Institute of Scientific and Technical Information of China (English)

    Xiao-mei WAN; Folker H.WITTMANN; Tie-jun ZHAO; Hong FAN

    2013-01-01

    Chloride content and the pH value of the pore solution in the neighborhood of steel reinforcement are decisive parameters for initiation and rate of corrosion.The pore solution of cement mortar and hardened cement paste has been expressed from the pore space by high pressure in the investigation.The influence of the water-cement ratio,age,and addition of chloride to the fresh mix on chloride content in the pore solution has been determined by ion chromatography.At the same time the pH value of the pore solution has been determined.The dissolved chloride content decreases with increase in the water-cement ratio.The amount of bound chloride increases with time,but it decreases with decreasing content of dissolved chloride in the pore solution.A significant influence of carbonation on the dissolved chloride content of the pore solution has been observed.With complete carbonation,the dissolved chloride content in cement mortar and hardened cement paste increases by a factor between 2 and 12.The bound chloride decreases by 27%-54%.As expected,the pH value decreases from around 13.2 to as low as 8.0 due to carbonation.It can be concluded that carbonation not only lowers the pH value but liberates bound chloride.This is one obvious reason why the combined action of chloride penetration and carbonation accelerates steel corrosion and shortens the service life of reinforced concrete structures.

  2. Resistance of Alkali-Activated Slag Concrete to Chloride-Induced Corrosion

    Directory of Open Access Journals (Sweden)

    Joon Woo Park

    2015-01-01

    Full Text Available The corrosion resistance of steel in alkali-activated slag (AAS mortar was evaluated by a monitoring of the galvanic current and half-cell potential with time against a chloride-contaminated environment. For chloride transport, rapid chloride penetration test was performed, and chloride binding capacity of AAS was evaluated at a given chloride. The mortar/paste specimens were manufactured with ground granulated blast-furnace slag, instead of Portland cement, and alkali activators were added in mixing water, including Ca(OH2, KOH and NaOH, to activate hydration process. As a result, it was found that the corrosion behavior was strongly dependent on the type of alkali activator: the AAS containing the Ca(OH2 activator was the most passive in monitoring of the galvanic corrosion and half-cell potential, while KOH, and NaOH activators indicated a similar level of corrosion to Portland cement mortar (control. Despite a lower binding of chloride ions in the paste, the AAS had quite a higher resistance to chloride transport in rapid chloride penetration, presumably due to the lower level of capillary pores, which was ensured by the pore distribution of AAS mortar in mercury intrusion porosimetry.

  3. A study of Trace Gold Chloride and Hydroxide Speciation in Weak Alkaline Solution by Ion Chromatography-Inductively Coupled Plasma Mass Spectrometry%离子色谱电感耦合等离子体质谱研究痕量氯金酸在弱碱性体系中金(Ⅲ)的形态

    Institute of Scientific and Technical Information of China (English)

    刘德晔; 朱醇; 马永建

    2012-01-01

    A method based on ion chromatography-inductively coupled plasma mass spectrometry(IC-ICP-MS) was developed to study trace gold chloride and hydroxide speciation in weak alkaline solu-tion. The results revealed that, the main compounds in weak alkaline solution were [AuCl2(OH)2]~ and [AuCKOH)3]-when the total Au mass was between 4. 0 30 ng. Unlike high HAuCl4 4H2O concentration, trace [AuCl2 (OH)2]~ could exist between pH 7. 0 to 10. 0, at least. Additional chlo-ride brought promotion to [AuCl2(OH)2]~ and reduction to CAuCl(OH)3]~. When pH was 7. 0 or chloride concentration was above 0. 050 mol/L, AuflE) would generate a compound which could not be flushed out of chromatography system. According to hydrolysis process. that compound was deduced as [AuCl3(OH)]-. The equilibrium constant K3 of [AuCl2(OH)2]- + OH ←[AuCl (OH)3]-+Cl always changed with pH values and chloride concentrations. Therefore, there might exist other factor to influence the trace Au(Ⅲ) hydrolysis.%采用离子色谱电感耦合等离子体质谱联用方法研究弱碱性体系下痕量氯金酸中Au(Ⅲ)的形态.结果表明:在弱碱性条件下,总金含量在4.0~30 ng之间,Au(Ⅲ)主要以[AuCl2( OH)2]-和[AuCl(OH)3]-的形式存在.与较高含量的氯金酸溶渡相比,痕量氯金酸溶液中的[AuCl2(OH)2]-至少可以在pH 7.0~10.0范围内存在.溶液外加的Cl-可使[AuCl2 (OH)2]-含量升高同时降低[AuCl (OH)3]-含量;当pH=7.0或Cl-浓度高于0.050 mol/L,会产生不随色谱流出的金络合物,根据水解过程推断该络合物为[AuC13 (OH)]-.在pH 8.0~10.0,Cl-浓度在0.000~0.020 mol/L时,[AuCl2(OH)2]-+OH-=[AuCl (OH)3]-+Cl-的水解平衡常数为不定值,说明痕量氯金酸的水解不仅受pH值和Cl-浓度影响,还受其它因素影响.

  4. Chloride sublimation of gold-arsenic concentrates

    International Nuclear Information System (INIS)

    Present article is devoted to chloride sublimation of gold-arsenic concentrates. The results of studies of chloride sublimation of gold-arsenic comprising concentrates of Chore deposit of Tajikistan are considered. It is found that by application sodium chloride for gold-arsenic comprising concentrates it is possible to extract gold and silver from flotation concentrates.

  5. 21 CFR 582.5446 - Manganese chloride.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Manganese chloride. 582.5446 Section 582.5446 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5446 Manganese chloride. (a) Product. Manganese chloride. (b) Conditions of use....

  6. Two-and Three-Dimensional Chloride Ingress into Fly Ash Concrete

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yunsheng; SUN Wei; CHEN Shudong; GUO Fei

    2011-01-01

    2D,3D chloride ion concentration at the edge and comer zones were systematically investigated for fly ash concretes made with different cement replacement percentage by fly ash (0%,10%,20%,40%,60%),water to binder ratios (0.3,0.35,0.4),and curing ages (28 d,90 d).An interaction effect caused by 2D and 3D diffusion could obviously be observed through the comparison with 1D testing results.In order to quantify the interaction effect,2D and 3D diffusion interaction coefficients was proposed in this paper.Finally,the changes of 2D and 3D interaction coefficients with the change in the free chloride ion concentration were given.The above research provide an insight into chloride ion attack on the edge and comer reinforcing bars of concrete structures in the field of civil engineering.

  7. Biomineralization of a Cadmium Chloride Nanocrystal by a Designed Symmetrical Protein.

    Science.gov (United States)

    Voet, Arnout R D; Noguchi, Hiroki; Addy, Christine; Zhang, Kam Y J; Tame, Jeremy R H

    2015-08-17

    We have engineered a metal-binding site into the novel artificial β-propeller protein Pizza. This new Pizza variant carries two nearly identical domains per polypeptide chain, and forms a trimer with three-fold symmetry. The designed single metal ion binding site lies on the symmetry axis, bonding the trimer together. Two copies of the trimer associate in the presence of cadmium chloride in solution, and very high-resolution X-ray crystallographic analysis reveals a nanocrystal of cadmium chloride, sandwiched between two trimers of the protein. This nanocrystal, containing seven cadmium ions lying in a plane and twelve interspersed chloride ions, is the smallest reported to date. Our results indicate the feasibility of using rationally designed symmetrical proteins to biomineralize nanocrystals with useful properties. PMID:26136355

  8. Pourbaix diagrams of actinides in molten chlorides using an indicating electrode for oxide ion activity; Etablissement de diagrammes de Pourbaix des actinides dans les chlorures fondus au moyen d'une electrode indicatrice de l'activite des ions oxyde

    Energy Technology Data Exchange (ETDEWEB)

    Lambertin, D.; Lacquement, J. [CEA Valrho, (DCC/DRRV/SPHA), 30 - Marcoule (France)

    2000-07-01

    Pyrochemical separation methods using high temperature molten salt media could emerge as promising and valuable routes compared with aqueous methods for separation and transmutation strategies for long-lived radionuclides. A good knowledge of the molten salt chemistry is essential for controlling these separations, and elementary data are required for molten halide salts, which can be readily provided by electrochemical methods. Applying the chemical principles of aqueous solutions to the molten salt media, Pourbaix diagrams - called in this case potential-oxo-acidity (pO{sup 2-}) - can be plotted. They offer a rapid and comprehensive view of the thermodynamic properties of selected elements in a solvent of interest. Two methods are available for preparing these diagrams. The first is based on available thermodynamic data on pure element oxide (and oxychloride) compounds and on element chloride activity coefficients in melt (which can be electrochemically determined). In this method, we consider the oxide anion exchange reactions between the pure compounds, water and hydrogen chloride. The second method is a direct and experimental determination of the oxo-acidic properties of the studied element chlorides in melts. Use of an Yttria-Stabilised Zirconia Membrane (YSZM) electrode (oxide anion selective electrode) helps determine the nature of the stable oxide compounds in melts as well as their stabilities. The YSZM is used with a silver/silver chloride reference system, and was developed 25 years ago. Two examples of Potential-acidity diagrams. Employing the first method and the determination of the standard potential of plutonium in LiCl-KCl and NaCl-KCl eutectic mixtures, potential-oxo-acidity diagrams were plotted for these melts at various temperatures. It was found that the stability domain for plutonium chloride depends on the melt composition (influence of oxide anion solvation). We also used the Omega acidity function - based on reaction (1) - which is a

  9. 氯离子对2种牙科常用合金耐腐蚀性的影响%Effect of chloride ion on corrosion of two commonly used dental alloys

    Institute of Scientific and Technical Information of China (English)

    陈蕾; 张维丹; 张媛媛

    2014-01-01

    Objective: To investigate the effect of chloride concentration on the corrosion of Co-Cr alloy and pure Ti in a simulated oral environment. Methods: The electrochemical corrosion tests of pure Ti and Co-Cr alloy were carried out in neutral artiifcial saliva solutions with different NaCl concentrations (0.9%, 2.0%, and 3.0%). hTe morphologies of corroded surface for pure Ti and Co-Cr alloy were observed by scanning electron microscope (SEM). Results: hTe changes in the self-corrosion potentials (Ecorr) for pure Ti and Co-Cr alloy in three kinds of artificial saliva solutions was not obvious. However, the self-corrosion current densities (Icorr) of pure Ti were much lower than those of Co-Cr. TheIcorr of Co-Cr alloy increased in a concentration-dependent manner of NaCl, whereas the breakdown potential (Eb) of Co-Cr alloy decreased in a concentration-dependent manner. hTe potential ranged for the breakdown of oxide film (Ev) was shortened in a concentration-dependent manner of NaCl. There was no obviousdifference in theIcorr of pure Ti with different concentrations of NaCl. hTe breakdown potential was not seen according to the polarization curves. Conclusion: In a certain range, the increase of the concentration of Cl- leads to accelerate the corrosion behavior of Co-Cr alloy, but it does not affect pure Ti.%目的:在模拟口腔环境下,探讨氯离子对钴铬合金和纯钛耐腐蚀性的影响。方法:通过对两种合金在不同NaCl(0.9%,2.0%,3.0%)浓度的中性人工唾液中进行电化学腐蚀指标测试并结合扫描电镜(SEM)扫描,观察其表面形貌。结果:钴铬合金和纯钛在三种人工唾液中的自腐蚀电位(Ecorr)的变化趋势无明显规律性,但是纯钛的自腐蚀电流密度(Icorr)明显小于钴铬合金。钴铬合金的自腐蚀电流密度随NaCl浓度的升高而增大,破裂电位值随NaCl浓度的升高而降低,氧化膜阳极破裂前的电位区间随NaCl浓度的升高而降低。纯钛的

  10. Evaluación del tripolifosfato de sodio como anticoagulante en determinaciones hematológicas en seres humanos Assessment of anticoagulant sodium tripolyphosphate used in hematologic determinations in human being

    OpenAIRE

    Lisbeth Rangel Matos; Maribel Quintero de Troconis; Anangelina Archile Contreras; Betty Benítez Payares; Maczy González Rincón; Ana Ruiz Medina; Enrique Márquez Salas; Jorge Herrera

    2009-01-01

    El propósito del presente estudio fue evaluar la utilidad del tripolifosfato de sodio (TPF) como anticoagulante en diferentes determinaciones hematológicas en seres humanos. Muestras de sangre venosa procedentes de adultos sanos de ambos sexos fueron anticoaguladas con TPF, sales dipotásicas del ácido etilendiaminotetraacético (EDTA) y citrato de sodio. Las muestras anticoaguladas con EDTA y citrato de sodio fueron utilizadas como controles. Al comparar los valores obtenidos en todas las prue...

  11. Ecuaciones para eliminar la interferencia de sueros hemolisados, ictéricos e hiperglucémicos en las determinaciones rutinarias de química clínica

    OpenAIRE

    Sánchez Rodríguez, Martha A; Rosa Colunga Reyes; Ma. del Pilar Cedillo Martínez

    2002-01-01

    Introducción: Las muestras hemolisadas, ictéricas o hiperglucémicas, pueden modificar cuantitativamente los resultados de una medición analítica por interferencia, ya que los métodos utilizados para las determinaciones en química clínica están basados en técnicas espectrofotométricas. Objetivo: Cuantificar la interferencia in vitro producida por la presencia en el suero de glucosa, bilirrubina y hemoglobina, a diferentes concentraciones, en las técnicas de urea, creatinina, ácido úrico y cole...

  12. Chloride diffusivity in hardened cement paste from microscale analyses and accounting for binding effects

    Science.gov (United States)

    Carrara, P.; De Lorenzis, L.; Bentz, D. P.

    2016-08-01

    The diffusion of chloride ions in hardened cement paste (HCP) under steady-state conditions and accounting for the highly heterogeneous nature of the material is investigated. The three-dimensional HCP microstructures are obtained through segmentation of x-ray images of real samples as well as from simulations using the cement hydration model CEMHYD3D. Moreover, the physical and chemical interactions between chloride ions and HCP phases (binding), along with their effects on the diffusive process, are explicitly taken into account. The homogenized diffusivity of the HCP is then derived through a least square homogenization technique. Comparisons between numerical results and experimental data from the literature are presented.

  13. Modeling of extraction equilibrium of Zn(II) from chloride solutions using TBP

    International Nuclear Information System (INIS)

    Zinc protective layers are commonly used to protect steel goods from corrosion. Solvent extraction and ion exchange can be used to remove zinc(II) from spent pickling solutions. The aim of presented work was to perform the detailed studies with tributyl phosphate taking into account different concentrations of zinc(II) and high concentrations both of proton and chloride ions. The obtained extraction isotherms of Zn(II) from chloride solutions were used to modeling extraction equilibrium, and equilibrium constant were calculated. The obtained results shown that zinc(II) could be effectively stripped from the organic phase with water

  14. CPP-603 Chloride Removal System Decontamination and Decommissioning

    International Nuclear Information System (INIS)

    The CPP-603 (annex) Chloride Removal System (CRS) Decontamination and Decommissioning (D ampersand D) Project is described in this report. The CRS was used for removing Chloride ions and other contaminants that were suspended in the waters of the underwater fuel storage basins in the CPP-603 Fuel Receiving and Storage Facility (FRSF) from 1975 to 1981. The Environmental Checklist and related documents, facility characterization, decision analysis', and D ampersand D plans' were prepared in 1991. Physical D ampersand D activities were begun in mid summer of 1992 and were completed by the end of November 1992. All process equipment and electrical equipment were removed from the annex following accepted asbestos and radiological contamination removal practices. The D ampersand D activities were performed in a manner such that no radiological health or safety hazard to the public or to personnel at the Idaho National Engineering Laboratory (INEL) occurred

  15. Sodium chloride's effect on self-assembly of diphenylalanine bilayer.

    Science.gov (United States)

    Kwon, Junpyo; Lee, Myeongsang; Na, Sungsoo

    2016-07-15

    Understanding self-assembling peptides becomes essential in nanotechnology, thereby providing a bottom-up method for fabrication of nanostructures. Diphenylalanine constitutes an outstanding building block that can be assembled into various nanostructures, including two-dimensional bilayers or nanotubes, exhibiting superb mechanical properties. It is known that the effect of the ions is critical in conformational and chemical interactions of bilayers or membranes. In this study, we analyzed the effect of sodium chloride on diphenylalanine bilayer using coarse-grained molecular dynamics simulations, and calculated the bending Young's modulus and the torsional modulus by applying normal modal analysis using an elastic network model. The results showed that sodium chloride dramatically increases the assembling efficiency and stability, thereby promising to allow the precise design and control of the fabrication process and properties of bio-inspired materials. © 2016 Wiley Periodicals, Inc. PMID:27241039

  16. Electrochemical synthesis and characterization of chloride doped polyaniline

    Indian Academy of Sciences (India)

    A M Pharhad Hussain; A Kumar

    2003-04-01

    Chloride doped polyaniline conducting polymer films have been prepared in a protic acid medium (HCl) by potentiodynamic method in an electrochemical cell and studied by cyclic voltammetry and FTIR techniques. The FTIR spectra confirmed Cl– ion doping in the polymers. The polymerization rate was found to increase with increasing concentration of aniline monomer. But the films obtained at high monomer concentration were rough having a nonuniform flaky polyaniline distribution. Results showed that the polymerization rate did not increase beyond a critical HCl concentration. Cyclic voltammetry suggested that, the oxidation-reduction current increased with an increase in scan rate and that the undoped polyaniline films were not hygroscopic whereas chloride doped polyaniline films were found to be highly hygroscopic.

  17. Fabrication and Performance of All-Solid-State Chloride Sensors in Synthetic Concrete Pore Solutions

    Directory of Open Access Journals (Sweden)

    Hongwei Deng

    2010-11-01

    Full Text Available One type of all-solid-state chloride sensor was fabricated using a MnO2 electrode and a Ag/AgCl electrode. The potentiometric response of the sensor to chloride in synthetic concrete pore solutions was systematically studied, and the polarization performance was also evaluated. The results show a good linear relationship between the potential reading of the sensor and the logarithm of chloride activity (concentration ranges from 0.05 to 5.0 M, and the potential value remains stable with increasing immersion time. The existence of K+, Ca2+, Na+ and SO42− ions have little influence on the potentiometric response of the sensor to chloride, but the pH has a significant influence on the potential value of the sensor at low chloride concentration. The potential reading of the sensor increases linearly with the solution temperature over the range from 5 to 45 °C. Meanwhile, an excellent polarization behavior is proven by galvanostatic and potentiodynamic tests. All of the results reveal that the developed sensor has a great potential for monitoring chloride ions in concrete environments.

  18. Fabrication and performance of all-solid-state chloride sensors in synthetic concrete pore solutions.

    Science.gov (United States)

    Gao, Xiaojian; Zhang, Jian; Yang, Yingzi; Deng, Hongwei

    2010-01-01

    One type of all-solid-state chloride sensor was fabricated using a MnO(2) electrode and a Ag/AgCl electrode. The potentiometric response of the sensor to chloride in synthetic concrete pore solutions was systematically studied, and the polarization performance was also evaluated. The results show a good linear relationship between the potential reading of the sensor and the logarithm of chloride activity (concentration ranges from 0.05 to 5.0 M), and the potential value remains stable with increasing immersion time. The existence of K(+), Ca(2+), Na(+) and SO(4) (2-) ions have little influence on the potentiometric response of the sensor to chloride, but the pH has a significant influence on the potential value of the sensor at low chloride concentration. The potential reading of the sensor increases linearly with the solution temperature over the range from 5 to 45 °C. Meanwhile, an excellent polarization behavior is proven by galvanostatic and potentiodynamic tests. All of the results reveal that the developed sensor has a great potential for monitoring chloride ions in concrete environments. PMID:22163467

  19. A novel device for quantitative measurement of chloride concentration by fluorescence indicator

    Science.gov (United States)

    Wang, Junsheng; Wu, Xudong; Chon, Chanhee; Gonska, Tanja; Li, Dongqing

    2012-02-01

    Cystic fibrosis (CF) is a life-threatening genetic disease. At present, the common method for diagnosis of CF is to detect the chloride concentration in sweat using ion-selective electrodes. However, the current sweat testing methods require a relatively large quantity of sweat sample, at least 25 µL, which is very difficult to obtain, especially for newborns. This paper presents a new method and a new device for rapid detection of the chloride concentration from a small volume of solution. In this method, the chloride concentration is determined quantitatively by the fluorescence intensity of MQAE, a chloride ion fluorescent indicator. In this device, the sample is carried by a small piece of filter paper on a cover glass exposed to an UV LED light source. The resulting fluorescent signals are detected by a Si photodiode. Data acquisition and processing are accomplished by LabVIEW software in a PDA. Based on the Stern-Volmer relationship, the effects of different parameters on the fluorescence intensity were analyzed. The observed significant difference between 40 and 60 mM (the borderline of chloride concentration for CF) is discussed in this paper. The results show that detection can be completed within 10 s. The minimum detectable volume of the chloride solution is 1 μL. The novel method and the device are of great potential for CF diagnosis.

  20. Neutron diffraction study of aluminum chloride imidazolium chloride molten salts

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, S. [Nisshin Steel Co. Ltd., Tokyo (Japan); Saboungi, M.L.; Suzuya, K. [Argonne National Lab., IL (United States); Koura, N. [Tokyo University of Science, Tokyo (Japan). Faculty of Science and Technology

    1994-02-01

    The structure of molten mixtures of (AlCl{sub 3}){sub x}(1-ethyl-3-methylimidazolium chloride){sub 1-x} was investigated by neutron diffraction techniques for x=0.46, 0.50, 0.60 and 0.67. Results derived from earlier ab initio molecular orbital (6-31G* basis set) computations for AlCl{sub 4}{sup {minus}}, Al{sub 2}Cl{sub 7}{sup {minus}}, and EMI{sup +} were used to calculate the diffraction patterns; the calculated contributions of each species are thus obtained and overall results are in good agreement with measurements.

  1. Chloride transport and its sensitivities to different boundary conditions in reclaimed soil solutions filled with fly ash

    Institute of Scientific and Technical Information of China (English)

    Xiao-Yang CHEN; Jia-Ping YAN; Shi-Wen ZHANG

    2013-01-01

    Chloride ion transport in reclaimed soil solutions filled with fly ash (FA) was investigated by measuring the hydraulic parameters (i.e.water retention curves and hydraulic conductivity) of three substrates,namely GSL,GFA,and CFA.Similar simulations were carried out under certain weather conditions.The different boundary conditions of chloride transport were also discussed from FA texture,cover soil thickness,groundwater table level,and initial chloride concentration.Furthcrmore,the sensitivities of chloride ions to these effect factors were analyzed.The results show that the different top soil thickness and initial chloride concentration have no effect on salinity of topsoil solution in the monitoring points,but they can clearly change the chloride concentration of FA layers.The sensibilities from top soil thickness and initial chloride content are exceedingly weak to the salinity balance based on two dimensions of the time and concentration.While the different FA texture and groundwater table not only affect the salinity equilibrium process of the whole reclaimed soil profile,but also change its balance state.Generally,coarse FA particles and high groundwater table can defer the salinity balance process of the reclaimed soil solution,and they also increase the chloride concentration of FA layer solutions,and even topsoil ones.

  2. Experimental investigation on the threshold chloride concentration for corrosion initiation in reinforced concrete structures

    International Nuclear Information System (INIS)

    The corrosion of steel reinforcements in concrete is of great importance in the view of safety and durability of reinforced concrete structures. This study is focused on the corrosion behavior of steel bars induced by internal chlorides in concrete. The main objective of this study is to determine the threshold chloride concentration causing depassivation and active corrosion of steel reinforcement in concrete. To examine the threshold concentration of chloride ion, the half-cell potential, the chemical composition of extracted pore solutions of concrete and the extent of corroded area of the specimens were measured. Major test variables include the added amount of chlorides in concrete, type of binder, and water-to-binder ratios. From the present comprehensive test results, the factors influencing threshold chloride concentration are investigated, and the rational ranges of threshold chloride concentration causing active corrosion of steels are proposed. The present study provides the realistic chloride limit for corrosion initiation of reinforced concrete structures, which can be used efficiently in the future technical specification. (authors)

  3. Chloride diffusivity in red mud-ordinary portland cement concrete determined by migration tests

    Directory of Open Access Journals (Sweden)

    Daniel Véras Ribeiro

    2011-01-01

    Full Text Available Red mud, which is a solid waste produced in the alumina production process, is classified as dangerous due to its high pH. In this work, the concentration of chlorides was monitored by measuring the conductivity of the anolyte, which initially was distilled water. The steady and nonsteady-state chloride diffusion coefficients were estimated from the "time lag"� and "equivalent time" between diffusion and migration experiments. The capillary water absorption, apparent porosity and pore size distribution of concretes were also analyzed. The addition of red mud apparently ensured lower chloride diffusion in the tested mixtures due to its superfine particle-size distribution and its "filler"� effect. Red mud lengthened the service life of the concrete to 35 years (double that of the reference concrete. This finding is very positive since it indicates a delay in the onset of the rebar corrosion process caused by the migration of chloride ions.

  4. Effect of Organic Inhibitors on Chloride Corrosion of Steel Rebars in Alkaline Pore Solution

    Directory of Open Access Journals (Sweden)

    Marina Cabrini

    2015-01-01

    Full Text Available The inhibition properties of aspartic and lactic acid salts are compared with nitrite ions with regard to their effect on critical chloride concentration. The tests were carried out on carbon steel specimens in simulated pore solutions with initial pH in the range of 12.6 to 13.8. The critical chloride concentrations were estimated through multiple specimen potentiostatic tests at potentials in the usual range for passive rebar in noncarbonated concrete structures. During tests, chloride ions were progressively added until all specimens showed localized attack, obtaining cumulative distribution curves reporting the fraction of corroded specimens as a function of chloride concentration. The presence of the organic inhibitors on the passivity film was detected by IR spectra. The results confirm that 0.1 M aspartate exhibits an inhibiting effect comparable with nitrite ions of the same concentration. Calcium lactate does not increase critical chloride concentration; however it appears to promote the formation of a massive scale, reducing the corrosion propagation.

  5. Synthesis of Zirconium Lower Chlorides

    International Nuclear Information System (INIS)

    This research is accurately related to the Halox concept of research reactor spent fuel element treatment.The aim of this project is to work the conditioning through selected chlorination of the element that make the spent fuel element. This research studied the physical chemistry conditions which produce formation of the lower zirconium chlorides through the reaction between metallic Zr and gaseous ZrCl4 in a silica reactor.This work focused special attention in the analysis and confrontation of the published results among the different authors in order to reveal coincidences and contradictions.Experimental section consisted in a set of synthesis with different reaction conditions and reactor design. After reaction were analyzed the products on Zr shavings and the deposit growth on wall reactor.The products were strongly dependent of reactor design. It was observed that as the distance between Zr and wall reactor increased greater was tendency to lower chlorides formation.In reactors with small distance the reaction follows other way without formation of lower chlorides.Analysis on deposit growth on reactor showed that may be formed to a mixture of SixZry intermetallics and zirconium oxides.Presence of oxygen in Zr and Zr-Si compounds on wall reactor reveals that there is an interaction between quartz and reactants.This interaction is in gaseous phase because contamination is observed in experiences where Zr was not in contact with reactor.Finally, it was made a global analysis of all experiences and a possible mechanism that interprets reaction ways is proposed

  6. Ion mixing, hydration, and transport in aqueous ionic systems

    International Nuclear Information System (INIS)

    The enhancement effect on the ion mobility of fluoride (and that of chloride) in a polycationic system, as the chloride content increases, is shown to also exist in other more simple ionic systems with cations such as the cesium ion and an organic ammonium ion. As the chloride content increases, in addition to the finding that there is more unbound water associated with the cation, we also observe that the average lifetime of a hydrogen bond decreases. This change to the hydrogen bonds is correlated to significant changes to both the structural and dynamical properties of water. The more disordered water structure and faster water dynamics are hypothesized to be also responsible for the enhanced ion mobilities. Furthermore, when either the chloride content or hydration level is changed, the self-diffusion constant of each co-ion changes by almost the same factor, implying the existence of a single universal transport mechanism that determines ion mobilities

  7. Effect of Chlorides on Conductivity and Dielectric Constant in Hardened Cement Mortar: NDT for Durability Evaluation

    Directory of Open Access Journals (Sweden)

    Sunkook Kim

    2016-01-01

    Full Text Available Dielectric constant and conductivity, the so-called EM properties (electromagnetic, are widely adopted for NDT (Nondestructive Technique in order to detect damage or evaluate performance of concrete without damage to existing RC (reinforced concrete. Among deteriorating agents, chloride ion is considered as one of the most critical threats due to rapid penetration and direct effect on steel corrosion. In the work, cement mortar samples with 3 w/c (water-to-cement ratios and 4 levels of chloride addition are considered. Conductivity and dielectric constant are measured in the normal frequency range. They increase with strength of mortar and more chloride ions due to denser pore formation. Furthermore, the behaviors of measured EM property are investigated with carbonation velocity and strength, which shows an attempt of application to durability evaluation through EM measurement.

  8. Crystal structure and functional characterization of a light-driven chloride pump having an NTQ motif.

    Science.gov (United States)

    Kim, Kuglae; Kwon, Soon-Kyeong; Jun, Sung-Hoon; Cha, Jeong Seok; Kim, Hoyoung; Lee, Weontae; Kim, Jihyun F; Cho, Hyun-Soo

    2016-01-01

    A novel light-driven chloride-pumping rhodopsin (ClR) containing an 'NTQ motif' in its putative ion conduction pathway has been discovered and functionally characterized in a genomic analysis study of a marine bacterium. Here we report the crystal structure of ClR from the flavobacterium Nonlabens marinus S1-08(T) determined under two conditions at 2.0 and 1.56 Å resolutions. The structures reveal two chloride-binding sites, one around the protonated Schiff base and the other on a cytoplasmic loop. We identify a '3 omega motif' formed by three non-consecutive aromatic amino acids that is correlated with the B-C loop orientation. Detailed ClR structural analyses with functional studies in E. coli reveal the chloride ion transduction pathway. Our results help understand the molecular mechanism and physiological role of ClR and provide a structural basis for optogenetic applications. PMID:27554809

  9. Cooper hydrometallurgy and extraction from chloride media

    International Nuclear Information System (INIS)

    The development of copper hydrometallurgy is presented and various processes proposed for copper recovery from sulphide concentrates are discussed. Leaching, extraction and stripping are considered, including reagents and processes. The extraction of copper from chloride solutions is discussed. Various extractants are presented and their use for copper transfer from chloride solutions to the organic phase and back to chloride and to sulphate solutions is discussed. (author) 4 refs

  10. Electrochemical Migration on Electronic Chip Resistors in Chloride Environments

    DEFF Research Database (Denmark)

    Minzari, Daniel; Jellesen, Morten Stendahl; Møller, Per;

    2009-01-01

    Electrochemical migration behavior of end terminals on ceramic chip resistors (CCRs) was studied using a novel experimental setup in varying sodium chloride concentrations from 0 to 1000 ppm. The chip resistor used for the investigation was 10-kΩ CCR size 0805 with end terminals made of 97Sn3Pb...... alloy. Anodic polarization behavior of the electrode materials was investigated using a microelectrochemical setup. Material makeup of the chip resistor was investigated using scanning electron microscopy (SEM)/energy dispersive spectroscopy and focused-ion-beam SEM. Results showed that the dissolution...

  11. 4-Hydroxy-1,2,6-trimethylpyridinium chloride monohydrate

    Directory of Open Access Journals (Sweden)

    T. Seethalakshmi

    2013-06-01

    Full Text Available In the crystal of the title hydrated molecular salt, C8H12NO+·Cl−·H2O, the water molecule makes two O—H...Cl hydrogen bonds, generating [010] zigzag chains of alternating water molecules and chloride ions. The cation is bonded to the chain by an O—H...O hydrogen bond and two weak C—H...Cl interactions. Weak aromatic π–π stacking [centroid–centroid separation = 3.5175 (15 Å] occurs between the chains.

  12. Corrosion Inhibition of Carbon Steel in Chloride and Sulfate Solutions

    Directory of Open Access Journals (Sweden)

    Amr Ahmed Elsayed

    2016-02-01

    Full Text Available Corrosion is a major problem in industry and in infrastructure; a huge sum of expenditure every year is spent on preventing, retarding, and repairing its damages. This work studies the engineering of an inhibitor for carbon steel metal used in the cooling systems containing high concentration of chloride and sulfate ions. For this purpose, the synergy between the dichromate, molybdate and nitrite inhibitors is examined and optimized to the best results. Moreover, care was taken that the proposed inhibitor is compliant with the environmental laws and regulations.

  13. Dechlorinating reaction of organic chlorides

    International Nuclear Information System (INIS)

    Dechlorination has been examined by the reaction between iron, aluminum powder or CaO and organic chlorides such as C2HCl3 and CH2Cl2. Progress of the reaction was analyzed with mass spectrometer. The reaction between iron and organic chloride was rapidly occurred at the temperature between 350 and 440degC in an atmosphere of argon. Above 380degC, more than 99.5% of C2HCl3 was decomposed within approximately 100 minutes. At 440degC, approximately 60% of C2HCl3 was decomposed by the reaction with aluminium powder within approximately 100 minutes. At 440degC, reaction between C2HCl3 and CaO powder were occurred rapidly in an atmosphere of argon to form CaCl2 and free carbon. Also in an atmosphere of air, nearly the same result was obtained. In this reaction, CaCl2, CO and CO2 were formed. CH2Cl2 was also decomposed by the reaction with iron at the temperature between 380 and 440degC. In the reaction, FeCl2, carbon and hydrogen were formed. CH3+ and CH4 were observed during the dechlorinating reaction of CH2Cl2. Variation in particle size of iron powder such as 100, 150 and 250 mesh did not affect the reaction rate. (author)

  14. Method of processing chloride waste

    International Nuclear Information System (INIS)

    In a method of applying molten salt electrolysis to chloride wastes discharged from a electrolytic refining step of a dry reprocessing step for spent fuels, and removed with transuranium elements of long half-decaying time, metals capable of alloying with alkali and alkaline earth metals under melting by electrolysis are used as a cathode material, and an electrolytic temperature is made higher than the melting point of salts in a molten salt electrolysis bath, to recover Li, Ca and Na as alloys with the cathode material in a first electrolysis step. Then, the electrolytic temperature is made higher than the melting point of the chloride salts remained in the bath after the electrolysis step described above by using the cathode material, to recover Ba, Rb, Sr and Cs of nuclear fission products also as alloys with the cathode material in a second electrolysis step. Accordingly, the amount of wastes formed can be reduced, and the wastes contain no heat generating nuclear fission elements. (T.M.)

  15. Hypertension: Salt restriction, sodium homeostasis, and other ions

    OpenAIRE

    Neeru Gupta; Kishan Kumar Jani; Nivedita Gupta

    2011-01-01

    Salt is composed of Sodium Chloride (NaCl) which in body water becomes essential electrolytes, viz., Sodium (Na >+ ) and Chloride (Cl >- ) ions, including in the blood and other extracellular fluids (ECF). Na >+ ions are necessary cations in muscle contractions and their depletion will effect all the muscles in body including smooth muscle contraction of blood vessels, a fact which is utilized in lowering the blood pressure. Na+ ions also hold water with them in the ECF. Na >+ homeostasis in ...

  16. Selective Measurement of Calcium and Sodium Ion Conductance Using Sub-Micropipette Probes with Ion Filters

    Science.gov (United States)

    Deng, Xiao Long; Takami, Tomohide; Son, Jong Wan; Kawai, Tomoji; Park, Bae Ho

    2012-02-01

    Selective ion currents in aqueous calcium chloride and sodium chloride solutions with concentrations of up to 1.0 M were observed with sub-micropipettes in which poly(vinyl chloride) (PVC) films containing ionophores selectively filtered cations. Calcium bis[4-(1,1,3,3-tetramethylbutyl)phenyl] phosphate (HDOPP-Ca) and bis[(12-crown-4)methyl]-2-dodecyl-2-methylmalonate [bis(12-crown-4)] were used as the ionophores to filter calcium and sodium ions, respectively. The selective ion current was observed using a low-current detection system developed from scanning tunneling microscopy. The approximate linear relationship between the ion concentration and ion current suggests that the sub-micropipette probe can be used to detect the intracellular local concentration of a specific ion up to 1.0 M.

  17. Factors influencing chloride deposition in a coastal hilly area and application to chloride deposition mapping

    OpenAIRE

    H. Guan; Love, A. J.; C. T. Simmons; Makhnin, O.; A. S. Kayaalp

    2010-01-01

    Chloride is commonly used as an environmental tracer for studying water flow and solute transport in the environment. It is especially useful for estimating groundwater recharge based on the commonly used chloride mass balance (CMB) method. Strong spatial variability in chloride deposition in coastal areas is one difficulty encountered in appropriately applying the method. A high-resolution bulk chloride deposition map in the coastal region is thus needed. The aim of this study is to construc...

  18. Factors influencing chloride deposition in a coastal hilly area and application to chloride deposition mapping

    OpenAIRE

    H. Guan; Love, A. J.; C. T. Simmons; Makhnin, O.; A. S. Kayaalp

    2010-01-01

    Chloride is commonly used as an environmental tracer for studying water flow and solute transport in the environment. It is especially useful for estimating groundwater recharge based on the commonly used chloride mass balance (CMB) method. Strong spatial variability in chloride deposition in coastal areas is one difficulty encountered in appropriately applying the method. A high-resolution bulk chloride deposition map in the coastal region is thus needed. The aim of this st...

  19. Crevice Corrosion of 321 Stainless Steel in Sodium Chloride Solutions

    International Nuclear Information System (INIS)

    Electrochemical techniques have been applied to study the crevice corrosion behaviour of stabilized 321 stainless steel in both 0.5, 1 and 2 M sodium chloride solutions at 25 and 80 degree . This type of stainless steel enjoys a good corrosion resistance especially in the heat affected zone (Haz) of welds. In this investigation the crevice corrosion of 321 stainless steel was studied in both bulk solution environments as well as in chloride solutions simulating those formed inside crevices. A metal-to-nonmetal crevice assembly, in which disc type specimens were faced to a PTFE crevice former, is used for bulk solution tests. Crevice-free specimens of solutions formed inside crevices (known as the critical crevice solutions, CCS). Cyclic potentiodynamic technique was used in evaluating the electrochemical corrosion performance of the alloy in bulk (0.5 and 1 M Nacl) environment. This revealed that both chloride ion concentration and temperature have a marked effect on the electrochemical parameters generally used for the evaluation of the crevice corrosion susceptibility. This included the corrosion potential. E corr. The passivity breakdown potential, Eb, and the protection potential, E p

  20. Formation of La{sup 3+}, Pr{sup 3+}, Eu{sup 3+}, Er{sup 3+}, and Lu{sup 3+} complexes with chloride ions, in aqueous medium; Formacion de complejos de La{sup 3+}, Pr{sup 3+}, Eu{sup 3+}, Er{sup 3+} y Lu{sup 3+} con iones cloruro, en medio acuoso

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez R, E.; Jimenez R, M.; Solache R, M. [ININ, 52750 La Marquesa, Estado de Mexico (Mexico)

    2007-07-01

    The constants of stability of the complexes of La{sup 3+}, Pr{sup 3+}, Eu{sup 3+}, Er{sup 3+}, and Lu{sup 3+} with Cl{sup -} ions, its were determined, in the aqueous medium of HCI - HClO{sub 4} and by a solvent extraction method. The dinonyl naphtalene sulfonic acid in n-heptane was used as extractant. The lanthanides concentration, it was measured by a VIS spectrophotometry method and by another radiochemical. The ions specific interaction theory (SIT) it was used for the extrapolation to ionic force 0 M. The results indicate that the stability constants of the LnCI{sup 2+} species diminishes when increasing the ion force and the charge density. (Author)

  1. Effects of concentration of sodium chloride solution on the pitting corrosion behavior of AISI 304L austenitic stainless steel

    Directory of Open Access Journals (Sweden)

    Asaduzzaman M.D.

    2011-01-01

    Full Text Available The pitting corrosion behavior of the austenitic stainless steel in aqueous chloride solution was investigated using electrochemical technique. Corrosion potential (Ecorr measurement, potentiodynamic experiments, potential-hold experiments in the passive range, and microscopic examination were used for the evaluation of corrosion characteristics. The experimental parameters were chloride ion concentration, immersion time and anodic-hold potential. Ecorr measurements along with microscopic examinations suggest that in or above 3.5 % NaCl at pH 2 pitting took place on the surface in absence of applied potential after 6 hour immersion. The potentiodynamic experiment reveals that Ecorr and pitting potential (Epit decreased and current density in the passive region increased with the increase of chloride ion concentrations. A linear relationship between Epit and chloride ion concentrations was found in this investigation. The analysis of the results suggests that six chloride ions are involved for the dissolution of iron ion in the pitting corrosion process of austenitic stainless steel.

  2. Ameliorating Effect of Chloride on Nitrite Toxicity to Freshwater Invertebrates with Different Physiology: a Comparative Study Between Amphipods and Planarians

    OpenAIRE

    Alonso, A.; Camargo, J.A.

    2008-01-01

    High nitrite concentrations in freshwater ecosystems may cause toxicity to aquatic animals. These living organisms can take nitrite up from water through their chloride cells, subsequently suffering oxidation of their respiratory pigments (hemoglobin, hemocyanin). Because NO2¿ and Cl¿ ions compete for the same active transport site, elevated chloride concentrations in the aquatic environment have the potential of reducing nitrite toxicity. Although this ameliorating effect is well documented ...

  3. Electrochemical Chloride extraction using external electrodes?

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Pedersen, Anne Juul

    cathode. However, some unwanted side effects can occur, including alkali-silica reaction and in some cases hydrogen embrittlement. It is also suggested also to use electrochemical chloride extraction in a preventive way in constructions where chloride induced corrosion is likely to be a problem after a...

  4. Chloride binding site of neurotransmitter sodium symporters

    DEFF Research Database (Denmark)

    Kantcheva, Adriana Krassimirova; Quick, Matthias; Shi, Lei;

    2013-01-01

    Neurotransmitter:sodium symporters (NSSs) play a critical role in signaling by reuptake of neurotransmitters. Eukaryotic NSSs are chloride-dependent, whereas prokaryotic NSS homologs like LeuT are chloride-independent but contain an acidic residue (Glu290 in LeuT) at a site where eukaryotic NSSs...

  5. Chloride ingress in cement paste and mortar

    DEFF Research Database (Denmark)

    Jensen, Ole Mejlhede; Hansen, Per Freiesleben; Coats, Alison M.; Glasser, Fred P.

    1999-01-01

    In this paper chloride ingress in cement paste and mortar is followed by electron probe microanalysis. The influence of several paste and exposure parameters on chloride ingress are examined (e.g., water-cement ratio, silica fume addition, exposure time, and temperature), The measurements are...

  6. Chloride ingress in cement paste and mortar

    DEFF Research Database (Denmark)

    Jensen, Ole Mejlhede; Hansen, Per Freiesleben; Coats, Alison M.;

    1999-01-01

    modelled on Fick's law modified by a term for chloride binding. Inclusion of chloride binding significantly improves the profile shape of the modelled ingress profiles. The presence of fine aggregate and formation of interfacial transition zones at paste-aggregate boundaries does not significantly affect...

  7. Reliability-Based Planning of Chloride Measurements

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Engelund, S.

    1996-01-01

    on measurements of the chloride content obtained from the given structure. In the present paper optimal planning of measurements of the chloride content in reinforced concrete structures is considered. It is shown how optimal experimental plans can be obtained using FORM-analysis. Bayesian statistics...

  8. Properties of silver chloride track detectors

    International Nuclear Information System (INIS)

    The experiments on preparation of silver chloride track detectors and their properties are described. The results of X-ray structural analysis and data on sensitivity to charged particles and actinic light of silver chloride crystals, doped with several elements, are presented. (orig.)

  9. Redox reactions in rare earth chloride molten electrolytes

    International Nuclear Information System (INIS)

    Rare earth (REM, Ln) solutions in chloride melts including MCI+LnCl3 mixtures, where M - alkali metals, were investigated by potentiometry, voltammetry, conductometry in wide concentration and temperature intervals. Findings present complete and trusty information on the valent state of rare earths, structure and composition of complex ions affecting essentially on properties of electrolytes. It is demonstrated that the coexistence of rare earth ions with different oxidation level formed as a result of possible redox reactions: 2Ln3+ + Ln ↔3Ln2+, Ln2+ + Ln↔2Ln+ and nM+ + Ln↔nM + Lnn+ appears sharply in thermodynamic and transport properties of molten Ln-LnCl3 and Ln-LnCl3-MCl systems

  10. Sorption of dodecyltrimethylammonium chloride (DTAC) to agricultural soils.

    Science.gov (United States)

    Xiang, Lei; Sun, Teng-Fei; Zheng, Mei-Jie; Li, Yan-Wen; Li, Hui; Wong, Ming-Hung; Cai, Quan-Ying; Mo, Ce-Hui

    2016-08-01

    Quaternary ammonium compounds (QACs) used as cationic surfactants are intensively released into environment to be pollutants receiving more and more concerns. Sorption of dodecyltrimethylammonium chloride (DTAC), one of commonly used alkyl QACs, to five types of agricultural soils at low concentrations (1-50mg/L) was investigated using batch experiments. DTAC sorption followed pseudo-second-order kinetics and reached reaction equilibrium within 120min. Both Freundlich model and Langmuir model fitted well with DTAC isotherm data with the latter better. DTAC sorption was spontaneous and favorable, presenting a physical sorption dominated by ion exchanges. Sorption distribution coefficient and sorption affinity demonstrated that soil clay contents acted as a predominant phase of DTAC sorption. DTAC could display a higher mobility and potential accumulation in crops in the soils with lower clay contents and lower pH values. Sorption of DTAC was heavily affected by ions in solution with anion promotion and cation inhibition. PMID:27101455

  11. Sugar-metal ion interactions: The coordination behavior of cesium ion with lactose, D-arabinose and L-arabinose

    Science.gov (United States)

    Jiang, Ye; Xue, Junhui; Wen, Xiaodong; Zhai, Yanjun; Yang, Limin; Xu, Yizhuang; Zhao, Guozhong; Kou, Kuan; Liu, Kexin; Chen, Jia'er; Wu, Jinguang

    2016-04-01

    The novel cesium chloride-lactose complex (CsCl·C12H22O10 (Cs-Lac), cesium chloride-D-arabinose and L-arabinose complexes (CsCl·C5H10O5, Cs-D-Ara and Cs-L-Ara) have been synthesized and characterized using X-ray diffraction, FTIR, FIR, THz and Raman spectroscopies. Cs+ is 9-coordinated to two chloride ions and seven hydroxyl groups from five lactose molecules in Cs-Lac. In the structures of CsCl-D-arabinose and CsCl-L-arabinose complexes, two kinds of Cs+ ions coexist in the structures. Cs1 is 10-coordinated with two chloride ions and eight hydroxyl groups from five arabinose molecule; Cs2 is 9-coordinated to three chloride ions and six hydroxyl groups from five arabinose molecules. Two coordination modes of arabinose coexist in the structures. α-D-arabinopyranose and α-L-arabinopyranose appear in the structures of Cs-D-Ara and Cs-L-Ara complexes. FTIR and Raman results indicate variations of hydrogen bonds and the conformation of the ligands after complexation. FIR and THz spectra also confirm the formation of Cs-complexes. Crystal structure, FTIR, FIR, THz and Raman spectra provide detailed information on the structure and coordination of hydroxyl groups to metal ions in the cesium chloride-lactose, cesium chloride-D- and L-arabinose complexes.

  12. Simple chloride sensors for continuous groundwater monitoring

    DEFF Research Database (Denmark)

    Thorn, Paul; Mortensen, John

    2012-01-01

    The development of chloride sensors which can be used for continuous, on-line monitoring of groundwater could be very valuable in the management of our coastal water resources. However, sensor stability, drift, and durability all need to be addressed in order for the sensors to be used in continu......The development of chloride sensors which can be used for continuous, on-line monitoring of groundwater could be very valuable in the management of our coastal water resources. However, sensor stability, drift, and durability all need to be addressed in order for the sensors to be used...... sensor remained responsive even at low chloride concentrations, where the conductivity electrode was no longer responding to changing chloride levels. With the results, it is believed that the simple chloride sensor could be used for continuous monitoring of groundwater quality....

  13. A metallacage encapsulating chloride as a probe for a solvation scale in ionic liquids.

    Science.gov (United States)

    Daguenet, Corinne; Dyson, Paul J

    2007-01-22

    With the purpose of assessing the reactivity of chloride ions dissolved in ionic liquids (ILs), a relative scale for the solvation of chloride is given for a series of ILs based on the bis(trifluoromethane)sulfonimide ([Tf(2)N]) anion and different cations, 1-butyl-3-methylimidazolium ([bmim]), 1-butyl-2,3-dimethylimidazolium ([bdmim]), 1-butyl-1-methylpyrrolidinium ([bmpy]), 1-butylpyridinium ([bpy]), 1-pentyl-1,1,1-triethylammonium ([C(5)e(3)am]), and 1-(2-hydroxy)ethyl-3-methylimidazolium ([mimeOH]). Insights into the solvation of chloride are achieved by the thermodynamic study of the reaction of dissociation of a chloride-templated nickel(II) metallacage performed at various temperatures by UV-visible spectroscopy in each IL. The order of chloride solvation [C(5)e(3)am][Tf(2)N] < [bmpy][Tf(2)N] < [bmim][Tf(2)N] ions in these ILs. PMID:17279818

  14. Enhanced surface photochemistry in chloride-nitrate ion mixtures

    Czech Academy of Sciences Publication Activity Database

    Wingen, L. M.; Moskun, A. C.; Johnson, S. N.; Thomas, J. L.; Roeselová, Martina; Tobias, D. J.; Kleinman, M. T.; Finlayson-Pitts, B. J.

    2008-01-01

    Roč. 10, č. 37 (2008), s. 5668-5677. ISSN 1463-9076 R&D Projects: GA MŠk LC512; GA MŠk 1P05ME798 Grant ostatní: NSF(US) CHE0431512 Institutional research plan: CEZ:AV0Z40550506 Keywords : aqueous sodium nitrate * air-water interface * molecular dynamics simulation * atmospheric aerosols Subject RIV: CC - Organic Chemistry Impact factor: 4.064, year: 2008

  15. Rapid chloride permeability test for durability study of carbon nanoreinforced mortar

    Science.gov (United States)

    Alafogianni, P.; Dalla, P. T.; Tragazikis, I. K.; Barkoula, N.-M.; Matikas, T. E.

    2015-03-01

    The addition of a conductive admixture in a cement-based material could lead to innovative products with multifunctional features. These materials are designed to possess enhanced properties, such as improved mechanical properties, electrical and thermal conductivity, and piezo-electric characteristics. Carbon nanotubes (CNTs) can be used as nano-reinforcement in cement-based materials because of their huge aspect ratio as well as their extremely large specific surface area. For cement-based composites, one of the major types of environmental attack is the chloride ingress, which leads to corrosion of the material and, subsequently, to the reduction of strength and serviceability of the structure. A common method of preventing such deterioration is to avert chlorides from penetrating the structure. The penetration of the concrete by chloride ions is a slow process. It cannot be determined directly in a time frame that would be useful as a quality control measure. Therefore, in order to assess chloride penetration, a test method that accelerates the process is needed, to allow the determination of diffusion values in a reasonable time. In the present research, nanomodified mortars with various concentrations of multi-wall carbon nanotubes (0.2% wt. cement CNTs - 0.6% wt. cement CNTs) were used. The chloride penetration in these materials was monitored according to ASTM C1202 standard. This is known as the Coulomb test or Rapid Chloride Permeability Test (RCPT).

  16. Insecticide sensitivity of native chloride and sodium channels in a mosquito cell line.

    Science.gov (United States)

    Jenson, Lacey J; Anderson, Troy D; Bloomquist, Jeffrey R

    2016-06-01

    The aim of this study was to investigate the utility of cultured Anopheles gambiae Sua1B cells for insecticide screening applications without genetic engineering or other treatments. Sua1B cells were exposed to the known insecticidal compounds lindane and DIDS, which inhibited cell growth at micromolar concentrations. In patch clamp studies, DIDS produced partial inhibition (69%) of chloride current amplitudes, and an IC50 of 5.1μM was determined for Sua1B cells. A sub-set of chloride currents showed no response to DIDS; however, inhibition (64%) of these currents was achieved using a low chloride saline solution, confirming their identity as chloride channels. In contrast, lindane increased chloride current amplitude (EC50=116nM), which was reversed when cells were bathed in calcium-free extracellular solution. Voltage-sensitive chloride channels were also inhibited by the presence of fenvalerate, a type 2 pyrethroid, but not significantly blocked by type 1 allethrin, an effect not previously shown in insects. Although no evidence of fast inward currents typical of sodium channels was observed, studies with fenvalerate in combination with veratridine, a sodium channel activator, revealed complete inhibition of cell growth that was best fit by a two-site binding model. The high potency effect was completely inhibited in the presence of tetrodotoxin, a specific sodium channel blocker, suggesting the presence of some type of sodium channel. Thus, Sua1B cells express native insect ion channels with potential utility for insecticide screening. PMID:27155485

  17. Influence of flexural fatigue on chloride threshold value for the corrosion of steels in Ca(OH){sub 2} solutions

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Linhua, E-mail: hhulhjiang@gmail.com [College of Mechanics and Materials, Hohai University, 1 Xikang Rd., Nanjing, 210098 (China); Hydraulic Engineering Research Center for New Materials and Protection, Jiangsu Province, 1 Xikang Rd., Nanjing, 210098 (China); Liu, Hao; Wang, Yongliang; Zhang, Yan; Song, Zijian; Xu, Jinxia; Jin, Ming; Jiang, Peng; Xu, Yi; Gao, Hailang [College of Mechanics and Materials, Hohai University, 1 Xikang Rd., Nanjing, 210098 (China)

    2015-08-15

    The flexural fatigue was enforced on reinforced concrete beam with stress level of 0.6 and different fatigue life cycles. Steels removed from the beams were soaked in the saturated Ca(OH){sub 2} solution, which was used as a simulated concrete pore solution. The NaCl solution was chosen as the source of chloride ions. The Chloride Threshold Values (CTV) were detected by combining the open-circuit potentials (E{sub corr}) with the corrosion current densities (i{sub corr}), which were obtained by electrochemical impedance spectroscopy (EIS). The changes of microstructure caused by the flexural fatigue were observed by scanning electron microscopy (SEM). The results showed that as the fatigue cycle times increased, the CTV decreased under a certain stress level and range of fatigue life cycles. The grains became finer and cracks appeared on the surface of the steels. While the capacitive arcs under no flexural fatigue decreased gradually with the addition of chloride ions, the ones under flexural fatigue presented no regularity. Cracks at the surface were expanded because of sustaining flexural fatigue, which degenerated the later resistance to chloride ions of the steels. - Highlights: • The influence of flexural fatigue on chloride threshold value was examined. • The chloride threshold values vary with different fatigue life cycles. • The corrosion behavior depends on the surface integrity of the steels.

  18. Influence of flexural fatigue on chloride threshold value for the corrosion of steels in Ca(OH)2 solutions

    International Nuclear Information System (INIS)

    The flexural fatigue was enforced on reinforced concrete beam with stress level of 0.6 and different fatigue life cycles. Steels removed from the beams were soaked in the saturated Ca(OH)2 solution, which was used as a simulated concrete pore solution. The NaCl solution was chosen as the source of chloride ions. The Chloride Threshold Values (CTV) were detected by combining the open-circuit potentials (Ecorr) with the corrosion current densities (icorr), which were obtained by electrochemical impedance spectroscopy (EIS). The changes of microstructure caused by the flexural fatigue were observed by scanning electron microscopy (SEM). The results showed that as the fatigue cycle times increased, the CTV decreased under a certain stress level and range of fatigue life cycles. The grains became finer and cracks appeared on the surface of the steels. While the capacitive arcs under no flexural fatigue decreased gradually with the addition of chloride ions, the ones under flexural fatigue presented no regularity. Cracks at the surface were expanded because of sustaining flexural fatigue, which degenerated the later resistance to chloride ions of the steels. - Highlights: • The influence of flexural fatigue on chloride threshold value was examined. • The chloride threshold values vary with different fatigue life cycles. • The corrosion behavior depends on the surface integrity of the steels

  19. Membrane chloride transport measured using a chloride-sensitive fluorescent probe

    International Nuclear Information System (INIS)

    Transport of chloride across cell membranes through exchange, cotransport, or conductive pathways is a subject of great biological importance. Current methods of measurement are restricted in their sensitivity, time resolution, and applicability. A new transport measurement technique has been developed on the basis of the fluorescence quenching by chloride of the dye 6-methoxy-N-(3-sulfopropyl)quinolinium (SPQ). SPQ fluorescence quenching by chloride is rapid and sensitive, with a greater than 50% decrease in fluorescence at 10 mM chloride. SPQ fluorescence is not altered by other physiological anions or by pH and can be used to measure both neutral and conductive transport processes. The high water solubility and membrane permeability properties of SPQ make it ideal for use in both membrane vesicles and cells. Chloride transport determined with SPQ was validated by measurement of erythrocyte chloride/anion exchange and membrane vesicle chloride conductance using 35SO4 uptake

  20. Chloride adsorption by calcined layered double hydroxides in hardened Portland cement paste

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Seyoon [School of Engineering, Kings College, University of Aberdeen, Aberdeen AB24 3UE (United Kingdom); Moon, Juhyuk, E-mail: juhyuk.moon@stonybrook.edu [Civil Engineering Program, Department of Mechanical Engineering, State University of New York at Stony Brook, New York 11794 (United States); Bae, Sungchul [Department of Civil and Environmental Engineering, University of California, Berkeley, CA 94720 (United States); Duan, Xiaonan [Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853 (United States); Giannelis, Emmanuel P. [Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853 (United States); Center for Refining and Petrochemicals, The Research Institute, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Monteiro, Paulo M. [Department of Civil and Environmental Engineering, University of California, Berkeley, CA 94720 (United States)

    2014-06-01

    This study investigated the feasibility of using calcined layered double hydroxides (CLDHs) to prevent chloride-induced deterioration in reinforced concrete. CLDHs not only adsorbed chloride ions in aqueous solution with a memory effect but also had a much higher binding capacity than the original layered double hydroxides (LDHs) in the cement matrix. We investigated this adsorption in hardened cement paste in batch cultures to determine adsorption isotherms. The measured and theoretical binding capacities (153 mg g{sup −1} and 257 mg g{sup −1}, respectively) of the CLDHs were comparable to the theoretical capacity of Friedel's salt (2 mol mol{sup −1} or 121 mg g{sup −1}), which belongs to the LDH family among cementitious phases. We simulated chloride adsorption by CLDHs through the cement matrix using the Fickian model and compared the simulation result to the X-ray fluorescence (XRF) chlorine map. Based on our results, it is proposed that the adsorption process is governed by the chloride transport through the cement matrix; this process differs from that in an aqueous solution. X-ray diffraction (XRD) analysis showed that the CLDH rebuilds the layered structure in a cementitious environment, thereby demonstrating the feasibility of applying CLDHs to the cement and concrete industries. - Highlights: • We examine the adsorption equilibrium and kinetics of CLDH in the hydrated cement. • CLDH capacity to bind chloride ions in the hydrated cement paste is determined. • We model chloride adsorption by CLDH through the cement matrix. • CLDH reforms the layered structure with ion adsorption in the cement matrix.

  1. Chloride adsorption by calcined layered double hydroxides in hardened Portland cement paste

    International Nuclear Information System (INIS)

    This study investigated the feasibility of using calcined layered double hydroxides (CLDHs) to prevent chloride-induced deterioration in reinforced concrete. CLDHs not only adsorbed chloride ions in aqueous solution with a memory effect but also had a much higher binding capacity than the original layered double hydroxides (LDHs) in the cement matrix. We investigated this adsorption in hardened cement paste in batch cultures to determine adsorption isotherms. The measured and theoretical binding capacities (153 mg g−1 and 257 mg g−1, respectively) of the CLDHs were comparable to the theoretical capacity of Friedel's salt (2 mol mol−1 or 121 mg g−1), which belongs to the LDH family among cementitious phases. We simulated chloride adsorption by CLDHs through the cement matrix using the Fickian model and compared the simulation result to the X-ray fluorescence (XRF) chlorine map. Based on our results, it is proposed that the adsorption process is governed by the chloride transport through the cement matrix; this process differs from that in an aqueous solution. X-ray diffraction (XRD) analysis showed that the CLDH rebuilds the layered structure in a cementitious environment, thereby demonstrating the feasibility of applying CLDHs to the cement and concrete industries. - Highlights: • We examine the adsorption equilibrium and kinetics of CLDH in the hydrated cement. • CLDH capacity to bind chloride ions in the hydrated cement paste is determined. • We model chloride adsorption by CLDH through the cement matrix. • CLDH reforms the layered structure with ion adsorption in the cement matrix

  2. The volumetric and thermochemical properties of YCl{sub 3}(aq), YbCl{sub 3}(aq), DyCl{sub 3}(aq), SmCl{sub 3}(aq), and GdCl{sub 3}(aq) at T=(288.15, 298.15, 313.15, and 328.15) K and p=0.1 MPa[Trivalent metal chlorides; Densities; Heat capacities; Single ion properties; Calorimetry; Densimetry

    Energy Technology Data Exchange (ETDEWEB)

    Hakin, Andrew W. E-mail: hakin@uleth.ca; Lukacs, Michael J.; Liu, Jin Lian; Erickson, Kristy

    2003-11-01

    Relative densities and massic heat capacities have been measured for acidified aqueous solutions of YCl{sub 3}(aq), YbCl{sub 3}(aq), DyCl{sub 3}(aq), SmCl{sub 3}(aq), and GdCl{sub 3}(aq) at T=(288.15, 298.15, 313.15, and 328.15) K and p=0.1 MPa. These measurements have been used to calculate experimental apparent molar volumes and heat capacities which, when used in conjunction with Young's rule, were used to calculate the apparent molar properties of the aqueous chloride salt solutions. The latter calculations required the use of volumetric and thermochemical data for aqueous solutions of hydrochloric acid that have been previously reported in the literature. The concentration dependences of the apparent molar properties have been modeled using Pitzer ion interaction equations to yield apparent molar volumes and heat capacities at infinite dilution. The temperature and concentration dependences of the apparent molar volumes and heat capacities of each trivalent salt system were modeled using modified Pitzer ion interaction equations. These equations utilized the revised Helgeson, Kirkham, and Flowers equations of state to model the temperature dependences of apparent molar volumes and heat capacities at infinite dilution. Calculated apparent molar volumes and heat capacities at infinite dilution have been used to calculate single ion properties for the investigated trivalent metal cations. These values have been compared to those previously reported in the literature. The differences between single ion values calculated in this study and those values calculated from thermodynamic data for aqueous perchlorate salts are also discussed.

  3. Chloride effect on the early photolysis intermediates of a gecko cone-type visual pigment.

    Science.gov (United States)

    Lewis, J W; Liang, J; Ebrey, T G; Sheves, M; Kliger, D S

    1995-05-01

    Nanosecond laser photolysis measurements were conducted on the cone-type visual pigment P521 in digitonin extracts of Tokay gecko (Gekko gekko) retina containing physiological chloride ion levels and also on samples which had been chloride depleted or which contained high levels (4 M) of chloride. Absorbance difference spectra were recorded at a sequence of time delays from 30 ns to 60 microseconds following excitation with a pulse of either 532- or 477-nm actinic light. Global analysis showed the kinetic decay data for gecko pigment P521 to be best fit by two exponential processes under all chloride conditions. The initial photoproduct detected had a broad spectrum characteristic of an equilibrated mixture of a Batho P521 intermediate with its blue-shifted intermediate (BSI P521) decay product. The first exponential process was assigned to the decay of this mixture to the Lumi P521 intermediate. The second exponential process was identified as the decay of Lumi P521 to Meta I P521. The initial photoproduct's spectrum exhibited a strong dependence on chloride concentration, indicating that chloride affects the composition of the equilibrated mixture of Batho P521 and BSI P521. These results suggest that the affinity for chloride is reduced approximately 5-fold in the Batho P521 intermediate and approximately 50-fold in the BSI P521 intermediate. Chloride concentration also affects the apparent decay rate of the equilibrated mixture. When the apparent decay rate is corrected for the composition of the equilibrated mixture, a relatively invariant microscopic rate constant is obtained for BSI decay (k = 1/55 ns-1).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7727442

  4. Liquid-liquid extraction of ion-association complexes of cobalt(II)-4-(2-pyridylazo)resorcinol with ditetrazolium salts

    OpenAIRE

    Divarova Vidka V.; Stojnova Kirila T.; Racheva Petya V.; Lekova Vanya D.; Dimitrov Atanas N.

    2015-01-01

    The formation and liquid-liquid extraction of ion-association complexes between Co(II)-4-(2-Pyridylazo)resorcinol (PAR) anionic chelates and cations of three ditetrazolium chlorides were studied: Blue Tetrazolium chloride (BTC), Neotetrazolium chloride (NTC) and Nitro Blue Tetrazolium chloride (NBT). The optimum conditions for the formation and solvent extraction of the ion-association comlpex chelates were determined. It has been found that in the systems ...

  5. Effect of fluorides and chlorides upon corrosion behavior of alloy C-22

    International Nuclear Information System (INIS)

    Alloy C-22 is one of the candidates to fabricate the external wall of the high level nuclear waste containers. These packages are designed to maintain isolation of the waste for a minimum of 10,000 years. During this period they must resist atmospheric corrosion. Electrochemical techniques such as cyclic potentiodynamic polarization, electrochemical impedance spectroscopy and variation of corrosion potential in time and non-electrochemical techniques such as X-ray fluorescence (XRF) and microscopy were applied to determine the effect of fluorides and chlorides upon general and localized corrosion of different microstructures of alloy C-22. The corrosion rates obtained were about 0.1 μm/year. Crevice corrosion was detected only in those solutions where chlorides ions were present. Fluoride ions affected the passivity and trans passivity behavior of the alloy. They produced higher current densities than chlorides in both ranges. There were no differences in corrosion behavior of the different microstructures. Mixtures of chlorides and fluorides seem to be more detrimental than the separated ions regarding to localized corrosion and trans passivity. (author)

  6. Chloride Transport in Undersea Concrete Tunnel

    Directory of Open Access Journals (Sweden)

    Yuanzhu Zhang

    2016-01-01

    Full Text Available Based on water penetration in unsaturated concrete of underwater tunnel, a diffusion-advection theoretical model of chloride in undersea concrete tunnel was proposed. The basic parameters including porosity, saturated hydraulic conductivity, chloride diffusion coefficient, initial water saturation, and moisture retention function of concrete specimens with two water-binder ratios were determined through lab-scale experiments. The variation of chloride concentration with pressuring time, location, solution concentration, initial saturation, hydraulic pressure, and water-binder ratio was investigated through chloride transport tests under external water pressure. In addition, the change and distribution of chloride concentration of isothermal horizontal flow were numerically analyzed using TOUGH2 software. The results show that chloride transport in unsaturated concrete under external water pressure is a combined effect of diffusion and advection instead of diffusion. Chloride concentration increased with increasing solution concentration for diffusion and increased with an increase in water pressure and a decrease in initial saturation for advection. The dominant driving force converted with time and saturation. When predicting the service life of undersea concrete tunnel, it is suggested that advection is taken into consideration; otherwise the durability tends to be unsafe.

  7. Shelf life of unrefrigerated succinylcholine chloride injection.

    Science.gov (United States)

    Boehm, J J; Dutton, D M; Poust, R I

    1984-02-01

    The shelf life of succinylcholine chloride injection at several pH values when stored at room temperature was evaluated. Solutions containing 20 mg/ml of succinylcholine chloride were stored at 25 and 40 degrees C. The reaction was studied at pH values ranging from 3.0 to 4.5. At two-week intervals, the solutions were assayed by high-pressure liquid chromatography. The initial amount of succinylcholine chloride in all samples was 100.1 +/- 2.37% of label claim. Hydrolysis of succinylcholine chloride in unbuffered solutions followed apparent zero-order kinetics. The pH range of maximum stability was found to be from 3.75 to 4.50. Succinylcholine chloride decomposed at a considerably higher rate at 40 degrees C. Allowing for the effects of pH adjustment during manufacture and degradation during shipping, losses of 7.0% and 9.0% potency can be expected after storage at 25 degrees C for four and six weeks, respectively. Succinylcholine Chloride Injection, USP, should be stored in the refrigerator; if unbuffered succinylcholine chloride injection complying with USP pH limits must be stored at room temperature, it should not be kept for longer than four weeks. PMID:6702837

  8. Factors influencing chloride deposition in a coastal hilly area and application to chloride deposition mapping

    Directory of Open Access Journals (Sweden)

    H. Guan

    2010-05-01

    Full Text Available Chloride is commonly used as an environmental tracer for studying water flow and solute transport in the environment. It is especially useful for estimating groundwater recharge based on the commonly used chloride mass balance (CMB method. Strong spatial variability in chloride deposition in coastal areas is one difficulty encountered in appropriately applying the method. A high-resolution bulk chloride deposition map in the coastal region is thus needed. The aim of this study is to construct a chloride deposition map in the Mount Lofty Ranges (MLR, a coastal hilly area of approximately 9000 km2 spatial extent in South Australia. We examined geographic (related to coastal distance, orographic, and atmospheric factors that may influence chloride deposition, using partial correlation and regression analyses. The results indicate that coastal distance, elevation, as well as terrain aspect and slope, appear to be significant factors controlling chloride deposition in the study area. Coastal distance accounts for 70% of spatial variability in bulk chloride deposition, with elevation, terrain aspect and slope an additional 15%. The results are incorporated into a de-trended residual kriging model (ASOADeK to produce a 1 km×1 km resolution bulk chloride deposition and concentration maps. The average uncertainty of the deposition map is about 20–30% in the western MLR, and 40–50% in the eastern MLR. The maps will form a useful basis for examining catchment chloride balance for the CMB application in the study area.

  9. Chloride substitution in sodium borohydride

    Science.gov (United States)

    Ravnsbæk, Dorthe B.; Rude, Line H.; Jensen, Torben R.

    2011-07-01

    The dissolution of sodium chloride and sodium borohydride into each other resulting in formation of solid solutions of composition Na(BH 4) 1- xCl x is studied. The dissolution reaction is facilitated by two methods: ball milling or combination of ball milling and annealing at 300 °C for three days of NaBH 4-NaCl samples in molar ratios of 0.5:0.5 and 0.75:0.25. The degree of dissolution is studied by Rietveld refinement of synchrotron radiation powder X-ray diffraction (SR-PXD) data. The results show that dissolution of 10 mol% NaCl into NaBH 4, forming Na(BH 4) 0.9Cl 0.1, takes place during ball milling. A higher degree of dissolution of NaCl in NaBH 4 is obtained by annealing resulting in solid solutions containing up to 57 mol% NaCl, i.e. Na(BH 4) 0.43Cl 0.57. In addition, annealing results in dissolution of 10-20 mol% NaBH 4 into NaCl. The mechanism of the dissolution during annealing and the decomposition pathway of the solid solutions are studied by in situ SR-PXD. Furthermore, the stability upon hydrogen release and uptake were studied by Sieverts measurements.

  10. Binary Nucleation of Water and Sodium Chloride

    Energy Technology Data Exchange (ETDEWEB)

    Nemec, Thomas [Institute of Thermomechanics ASCR, Prague, Czech Republic; Marsik, Frantisek [Institute of Thermomechanics ASCR, Prague, Czech Republic; Palmer, Donald [ORNL

    2005-01-01

    Nucleation processes in the binary water-sodium chloride system are investigated in the sense of the classical nucleation theory (CNT). The CNT is modified to be able to handle the electrolytic nature of the system and is employed to investigate the acceleration of the nucleation process due to the presence of sodium chloride in the steam. This phenomenon, frequently observed in the Wilson zone of steam turbines, is called early condensation. Therefore, the nucleation rates of the water-sodium chloride mixture are of key importance in the power cycle industry.

  11. Ion-Selective Detection with Glass Nanopipette for Living Cells

    Science.gov (United States)

    Takami, T.; Son, J. W.; Kang, E. J.; Deng, X. L.; Kawai, T.; Lee, S.-W.; Park, B. H.

    2013-05-01

    We developed a method to probe local ion concentration with glass nanopipette in which poly(vinyl chloride) membrane containing ionophore for separate ion detection is prepared. Here we demonstrate how ion-selective detections are available for living cells such as HeLa cell, rat vascular myocyte, and neuron cell.

  12. Specific ion effects on membrane potential and the permselectivity of ion exchange membranes

    KAUST Repository

    Geise, Geoffrey M.

    2014-08-26

    © the Partner Organisations 2014. Membrane potential and permselectivity are critical parameters for a variety of electrochemically-driven separation and energy technologies. An electric potential is developed when a membrane separates electrolyte solutions of different concentrations, and a permselective membrane allows specific species to be transported while restricting the passage of other species. Ion exchange membranes are commonly used in applications that require advanced ionic electrolytes and span technologies such as alkaline batteries to ammonium bicarbonate reverse electrodialysis, but membranes are often only characterized in sodium chloride solutions. Our goal in this work was to better understand membrane behaviour in aqueous ammonium bicarbonate, which is of interest for closed-loop energy generation processes. Here we characterized the permselectivity of four commercial ion exchange membranes in aqueous solutions of sodium chloride, ammonium chloride, sodium bicarbonate, and ammonium bicarbonate. This stepwise approach, using four different ions in aqueous solution, was used to better understand how these specific ions affect ion transport in ion exchange membranes. Characterization of cation and anion exchange membrane permselectivity, using these ions, is discussed from the perspective of the difference in the physical chemistry of the hydrated ions, along with an accompanying re-derivation and examination of the basic equations that describe membrane potential. In general, permselectivity was highest in sodium chloride and lowest in ammonium bicarbonate solutions, and the nature of both the counter- and co-ions appeared to influence measured permselectivity. The counter-ion type influences the binding affinity between counter-ions and polymer fixed charge groups, and higher binding affinity between fixed charge sites and counter-ions within the membrane decreases the effective membrane charge density. As a result permselectivity decreases. The

  13. Catastrophic event modeling. [lithium thionyl chloride batteries

    Science.gov (United States)

    Frank, H. A.

    1981-01-01

    A mathematical model for the catastrophic failures (venting or explosion of the cell) in lithium thionyl chloride batteries is presented. The phenomenology of the various processes leading to cell failure is reviewed.

  14. Monoclonal antibodies to the apical chloride channel in Necturus gallbladder inhibit the chloride conductance.

    OpenAIRE

    Finn, A L; Tsai, L M; Falk, R J

    1989-01-01

    Monoclonal antibodies raised by injecting Necturus gallbladder cells into mice were tested for their ability to inhibit the apical chloride conductance induced by elevation of cellular cAMP. Five of these monoclonal antibodies bound to the apical cells, as shown by indirect immunofluorescence microscopy, and inhibited the chloride conductance; one antibody that bound only to subepithelial smooth muscle, by indirect immunofluorescence microscopy, showed no inhibition of chloride transport. The...

  15. Factors influencing chloride deposition in a coastal hilly area and application to chloride deposition mapping

    OpenAIRE

    H. Guan; Love, A. J.; C. T. Simmons; A. S. Kayaalp

    2009-01-01

    Chloride is commonly used as an environmental tracer for studying water flow and solute transport in the environment. It is especially useful for estimating groundwater recharge based on the commonly used chloride mass balance (CMB) method. Strong spatial variability in chloride deposition in coastal areas is one difficulty encountered in appropriately applying the CMB approach. Furthermore, intensive vegetation clearance for agriculture, for example during the European settlement in many...

  16. Telomerization of Vinyl Chloride with Chloroform Initiated by Ferrous Chloride-Dimethylacetamide under Ultrasonic Conditions

    Directory of Open Access Journals (Sweden)

    Hua Qian

    2015-01-01

    Full Text Available Telomerization of vinyl chloride with chloroform was investigated using ferrous chloride-dimethylacetamide system, and 42.1% yield, more than four times the one reported before, was achieved. The addition of ultrasound further improved the reaction and yield was raised to 51.9% with trace byproducts at highly reduced reaction time and temperature. Ferrous chloride-dimethylacetamide under ultrasonic irradiation acts as a very efficient catalyst system for the 1 : 1 telomerization.

  17. The kinetics of the hydrogen chloride oxidation

    Directory of Open Access Journals (Sweden)

    Gonzalez Martinez Isai

    2013-01-01

    Full Text Available Hydrogen chloride (HCl oxidation has been investigated on technical membrane electrode assemblies in a cyclone flow cell. Influence of Nafion loading, temperature and hydrogen chloride mole fraction in the gas phase has been studied. The apparent kinetic parameters like reaction order with respect to HCl, Tafel slope and activation energy have been determined from polarization data. The apparent kinetic parameters suggest that the recombination of adsorbed Cl intermediate is the rate determining step.

  18. Synthesis of Macrocyclic Ionophore for the Development of Highly Selective Chloride Sensor

    Directory of Open Access Journals (Sweden)

    Sameena Mehtab

    2015-03-01

    Full Text Available The macrocyclic ligands 3,8,12,17-tetramethyl-2,18,9,11-bipyridyl-1,4,7,10,13,16-hexaazacyclooctadecanetetrahydro bromide has been synthesized and explored as suitable ionophores for chloride selective membrane sensors. It displays Nernstian behavior (59.2 mV decade-1 across the range of 4.1 × 10-8 to 1.0 × 10-2 M. The detection limit of the electrode is ~ 15 nM and the response time and life times are 14 s and eight weeks respectively over a wide pH range (3.5 - 9.5. Interference from other anions is very low and it can be used as indicator electrode in the potentiometric titration of chloride ions and to determine chloride in agricultural soil water samples.

  19. Control and monitoring of the localized corrosion of zirconium in acidic chloride solutions

    International Nuclear Information System (INIS)

    Zirconium in acidic chloride solutions which are contaminated with ferric or cupric cations is prone to localized corrosion. This tendency can be reduced by ensuring that the zirconium surface is clean and smooth. In this paper, the effect of surface condition on the localized corrosion of zirconium in acidic chloride solutions is predicted with potentiodynamic scans. These predictions are confirmed by weight loss tests on various combinations of surface finish and acid concentrations. A real time indication of localized corrosion is seen by monitoring the electrochemical noise produced between two similar electrodes immersed in an acidic chloride solutions. Electrochemical noise monitoring correlates well with the predictions from potentiodynamic and weight loss experiments. The electrochemical noise results show that while an elevated (more anodic) potential caused by ferric ion contamination may be a necessary condition for localized corrosion, it is not a sufficient condition: A smooth, clean zirconium surface reduces the localized corrosion of zirconium

  20. The evaluation of organic inhibitors for the protection of grade 5 titanium in chloride media

    International Nuclear Information System (INIS)

    The corrosion failures of titanium and titanium alloys are inevitably associated with the non-observance of environmental limits prescribed in corrosion handbooks, such as its use in solutions chloride. Titanium alloys are often used in the thermal transfer technology especially in the heat exchangers cooled with sea cooled water. However, it is not indicated its use in strong oxidant and any concentrated chloride environments. For the evaluation of grade 5 titanium alloy samples behaviour in solutions containing chloride ions in presence, respectively, absence of some organic inhibitors were performed by potentiodynamic polarization method. On the basis of our experimental results we consider that the most adequate inhibitor for the system Ti-5 alloys/0.083M NaCl solution is the resorcinol. (authors)

  1. Crystal structure of tetraethylammonium chloride 3,4,5,6-tetrafluoro-1,2-diiodobenzene

    Directory of Open Access Journals (Sweden)

    Jasmine Viger-Gravel

    2015-05-01

    Full Text Available Equimolar quantities of tetraethylammonium chloride (Et4NCl and 3,4,5,6-tetrafluoro-1,2-diiodobenzene (o-DITFB or o-C6F4I2 have been co-crystallized in a solution of dichloromethane yielding a pure halogen-bonded compound, 3,4,5,6-tetrafluoro-1,2-diiodobenzene–tetraethyl ammonium chloride (2/1, Et4N+·Cl−·2C6F4I2, in the form of translucent needles. [(Et4NCl(o-C6F4I22] packs in the C2/c space group. The asymmetric unit includes one molecule of DITFB, one Et4N+ cation located on a twofold rotation axis, and one chloride anion also located on a twofold rotation symmetry axis. This compound has an interesting halogen-bonding environment surrounding the halide. Here, the chloride anion acts as a tetradentate halogen bond acceptor and forms a distorted square-pyramidal geometry, with I...Cl−...I angles of 80.891 (6 and 78.811 (11°, where two crystallographically distinct iodine atoms form halogen bonds with the chloride anion. Resulting from that square-pyramidal geometry are short contacts between some of the adjacent F atoms. Along the b axis, the halogen-bonding interaction results in a polymeric network, producing a sheet in which the two closest chloride ions are 7.8931 (6 Å apart. The Et4N+ cation alternates in columns with the halide ion. The expected short contacts (shorter than the sum of their van der Waals radii are observed for the halogen bonds [3.2191 (2 and 3.2968 (2 Å], as well as almost linear angles [170.953 (6 and 173.529 (6°].

  2. 49 CFR 179.102-17 - Hydrogen chloride, refrigerated liquid.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Hydrogen chloride, refrigerated liquid. 179.102-17...) § 179.102-17 Hydrogen chloride, refrigerated liquid. Each tank car used to transport hydrogen chloride... on or after March 16, 2009 used for the transportation of hydrogen chloride, refrigerated...

  3. 21 CFR 178.3290 - Chromic chloride complexes.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Chromic chloride complexes. 178.3290 Section 178... SANITIZERS Certain Adjuvants and Production Aids § 178.3290 Chromic chloride complexes. Myristo chromic chloride complex and stearato chromic chloride complex may be safely used as release agents in the...

  4. Determination of persimmon leaf chloride contents using near-infrared spectroscopy (NIRS).

    Science.gov (United States)

    de Paz, José Miguel; Visconti, Fernando; Chiaravalle, Mara; Quiñones, Ana

    2016-05-01

    Early diagnosis of specific chloride toxicity in persimmon trees requires the reliable and fast determination of the leaf chloride content, which is usually performed by means of a cumbersome, expensive and time-consuming wet analysis. A methodology has been developed in this study as an alternative to determine chloride in persimmon leaves using near-infrared spectroscopy (NIRS) in combination with multivariate calibration techniques. Based on a training dataset of 134 samples, a predictive model was developed from their NIR spectral data. For modelling, the partial least squares regression (PLSR) method was used. The best model was obtained with the first derivative of the apparent absorbance and using just 10 latent components. In the subsequent external validation carried out with 35 external data this model reached r (2) = 0.93, RMSE = 0.16 % and RPD = 3.6, with standard error of 0.026 % and bias of -0.05 %. From these results, the model based on NIR spectral readings can be used for speeding up the laboratory determination of chloride in persimmon leaves with only a modest loss of precision. The intermolecular interaction between chloride ions and the peptide bonds in leaf proteins through hydrogen bonding, i.e. N-H···Cl, explains the ability for chloride determinations on the basis of NIR spectra. Graphical Abstract The NIRS-PLSR alternative to the wet reference analytical method for chloride determination in persimmon leaves saves lab work in exchange of a modest loss of precissionᅟ. PMID:26935930

  5. Meso-scale modeling of chloride diffusion in concrete with consideration of effects of time and temperature

    Institute of Scientific and Technical Information of China (English)

    Li-cheng WANG; Tamon UEDA

    2009-01-01

    A meso-scale truss network model was developed to predict chloride diffusion in concrete.The model regards concrete as a three-phase composite of mortar matrix,coarse aggregates,and the interfacial transition zone (ITZ) between the mortar matrix and the aggregates.The diffusion coefficient of chloride in the mortar and the ITZ can be analytically determined with only the water-to-cement ratio and volume fraction of fine aggregates.Fick's second law of diffusion was used as the governing equation for chloride diffusion in a homogenous medium (e.g.,mortar);it was discretized and applied to the truss network model.The solution procedure of the truss network model based on the diffusion law and the meso-scale composite structure of concrete is outlined.Additionally,the dependence of the diffusion coefficient of chloride in the mortar and the ITZ on exposure duration and temperature is taken into account to illustrate their effect on chloride diffusion coefficient.The numerical results show that the exposure duration and environmental temperature play important roles in the diffusion rate of chloride ions in concrete.It is also concluded that the meso-scale truss network model can be applied to chloride transport analysis of damaged (or cracked) concrete.

  6. Factors influencing chloride deposition in a coastal hilly area and application to chloride deposition mapping

    Directory of Open Access Journals (Sweden)

    H. Guan

    2009-09-01

    Full Text Available Chloride is commonly used as an environmental tracer for studying water flow and solute transport in the environment. It is especially useful for estimating groundwater recharge based on the commonly used chloride mass balance (CMB method. Strong spatial variability in chloride deposition in coastal areas is one difficulty encountered in appropriately applying the CMB approach. Furthermore, intensive vegetation clearance for agriculture, for example during the European settlement in many coastal areas of Australia, may have perturbed catchment chloride balance conditions for appropriate use in CMB applications. In order to deal with these issues, a high resolution chloride deposition map in the coastal region is needed. In this study, we examined geographic, orographic, and atmospheric factors influencing chloride deposition in the Mount Lofty Ranges (MLR, a coastal hilly area of approximately 9000 km2 spatial extent in South Australia, using partial correlation and regression analyses. The results indicate that coastal distance, and terrain aspect and slope are two most significant factors controlling chloride deposition. Coastal distance accounts for 65% spatial variability in chloride deposition, with terrain aspect and slope for 8%. The deposition gradient is about 0.08 gm-2 year-1 km-1 as one progresses inland. The results are incorporated into a published de-trended residual kriging approach (ASOADeK to produce a 1 km×1 km resolution annual chloride deposition map and a bulk precipitation chloride concentration map. The average uncertainty of the deposition map is about 30% in the western MLR, and over 50% in the eastern MLR. The maps will form a very useful basis for examining catchment chloride balances for use in the CMB application in the study area.

  7. Basolateral K+ channel involvement in forskolin-activated chloride secretion in human colon.

    Science.gov (United States)

    McNamara, B; Winter, D C; Cuffe, J E; O'Sullivan, G C; Harvey, B J

    1999-08-15

    1. In this study we investigated the role of basolateral potassium transport in maintaining cAMP-activated chloride secretion in human colonic epithelium. 2. Ion transport was quantified in isolated human colonic epithelium using the short-circuit current technique. Basolateral potassium transport was studied using nystatin permeabilization. Intracellular calcium measurements were obtained from isolated human colonic crypts using fura-2 spectrofluorescence imaging. 3. In intact isolated colonic strips, forskolin and prostaglandin E2 (PGE2) activated an inward transmembrane current (ISC) consistent with anion secretion (for forskolin DeltaISC = 63.8+/-6.2 microA cm(-2), n = 6; for PGE2 DeltaISC = 34.3+/-5.2 microA cm(-2), n = 6). This current was inhibited in chloride-free Krebs solution or by inhibiting basolateral chloride uptake with bumetanide and 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid DIDS). 4. The forskolin- and PGE2-induced chloride secretion was inhibited by basolateral exposure to barium (5 mM), tetrapentylammonium (10 microM) and tetraethylammonium (10 mM). 5. The transepithelial current produced under an apical to serosal K+ gradient in nystatin-perforated colon is generated at the basolateral membrane by K+ transport. Forskolin failed to activate this current under conditions of high or low calcium and failed to increase the levels of intracellular calcium in isolated crypts 6. In conclusion, we propose that potassium recycling through basolateral K+ channels is essential for cAMP-activated chloride secretion. PMID:10432355

  8. Laboratory method to estimate hydrogen chloride emission potential before incineration of a waste. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, M.R.; Albritton, J.R.; Jayanty, R.K.M.

    1990-07-01

    A laboratory method has been developed to provide an estimate of the amount of hydrogen chloride gas that will form during incineration of a waste. The method involves incineration of a sample of the waste at 900 C in a tube furnace, removal of particles from the resulting gases by filtration at 250 F (120 C), collection of hydrogen chloride gas in a water-filled impinger, and measurement of the collected HCl as chloride using a standard ion chromatography/conductimetric detection method. Duplicate experimental runs were conducted with quartz and with INCONEL components in the incineration zone of the apparatus. The two materials gave quite different results, which indicates some surface phenomenon may be involved. Results with quartz components indicated that organochlorine is essentially completely converted to HCl. Very ionic inorganic chlorides (e.g., KCl and NaCl) formed little or no HCl when incinerated in zero grade air (3ppm water and 1 ppm total hydrocarbon) but gave large amounts of HCl (20-80% conversion) if the incineration atmosphere contained 2.4-5.0% water vapor, which contains hydrogen for HCl formation. Results with less ionic inorganic chloride (FeCl3) and with chlorine in a positive oxidation state (NaCl solution) indicated significant conversion to HCl, especially in the presence of hydrogen from water vapor. In all cases, the presence of water vapor increased the amount of HCl formed, but INCONEL was judged less suitable than quartz because INCONEL gave low recovery of organohalogen as HCl.

  9. GmCLC1 Confers Enhanced Salt Tolerance through Regulating Chloride Accumulation in Soybean.

    Science.gov (United States)

    Wei, Peipei; Wang, Longchao; Liu, Ailin; Yu, Bingjun; Lam, Hon-Ming

    2016-01-01

    The family of chloride channel proteins that mediate Cl(-) transportation play vital roles in plant nutrient supply, cellular action potential and turgor pressure adjustment, stomatal movement, hormone signal recognition and transduction, Cl(-) homeostasis, and abiotic and biotic stress tolerance. The anionic toxicity, mainly caused by chloride ions (Cl(-)), on plants under salt stress remains poorly understood. In this work, we investigated the function of soybean Cl(-)/H(+) antiporter GmCLC1 under salt stress in transgenic Arabidopsis thaliana, soybean, and yeast. We found that GmCLC1 enhanced salt tolerance in transgenic A. thaliana by reducing the Cl(-) accumulation in shoots and hence released the negative impact of salt stress on plant growth. Overexpression of GmCLC1 in the hairy roots of soybean sequestered more Cl(-) in their roots and transferred less Cl(-) to their shoots, leading to lower relative electrolyte leakage values in the roots and leaves. When either the soybean GmCLC1 or the yeast chloride transporter gene, GEF1, was transformed into the yeast gef1 mutant, and then treated with different chloride salts (MnCl2, KCl, NaCl), enhanced survival rate was observed. The result indicates that GmCLC1 and GEF1 exerted similar effects on alleviating the stress of diverse chloride salts on the yeast gef1 mutant. Together, this work suggests a protective function of GmCLC1 under Cl(-) stress. PMID:27504114

  10. Effects of pH and chloride concentration on pitting corrosion of AA6061 aluminum alloy

    Energy Technology Data Exchange (ETDEWEB)

    Zaid, B. [Division de Technologie du Combustible, Departement de Metallurgie, Centre de Recherche Nucleaire de Draria, BP. 43 Seballa, Draria (Algeria)], E-mail: zaidbachir@yahoo.com; Saidi, D. [Division de Technologie du Combustible, Departement de Metallurgie, Centre de Recherche Nucleaire de Draria, BP. 43 Seballa, Draria (Algeria); Benzaid, A. [Divisionde Physique et Application Nucleaires, Departement Application Nucleaires, Centre de Recherche Nucleaire de Draria, BP. 43 Seballa, Draria (Algeria); Hadji, S. [Division de Technologie du Combustible, Departement du combustible, Centre de Recherche Nucleaire de Draria, BP. 43 Seballa, Draria (Algeria)

    2008-07-15

    Effects of pH solution and chloride (Cl{sup -}) ion concentration on the corrosion behaviour of alloy AA6061 immersed in aqueous solutions of NaCl have been investigated using measurements of weight loss, potentiodynamic polarisation, linear polarisation, cyclic polarisation experiment combined with open circuit potential transient technique and optical or scanning electron microscopy. The corrosion behaviour of the AA6061 aluminum alloy was found to be dependant on the pH and chloride concentration [NaCl] of solution. In acidic or slightly neutral solutions, general and pitting corrosion occurred simultaneously. In contrast, exposure to alkaline solutions results in general corrosion. Experience revealed that the alloy AA6061 was susceptible to pitting corrosion in all chloride solution of concentration ranging between 0.003 wt% and 5.5 wt% NaCl and an increase in the chloride concentration slightly shifted both the pitting E{sub pit} and corrosion E{sub cor} potentials to more active values. In function of the conditions of treatment, the sheets of the alloy AA6061 undergo two types of localised corrosion process, leading to the formation of hemispherical and crystallographic pits. Polarisation resistance measurements in acidic (pH = 2) and alkaline chloride solutions (pH = 12) which are in good agreement with those of weight loss, show that the corrosion kinetic is minimised in slightly neutral solutions (pH = 6)

  11. Synthesis and characterization of zinc chloride containing poly(acrylic acid) hydrogel by gamma irradiation

    International Nuclear Information System (INIS)

    In this study, the characterization of zinc chloride incorporated into a poly(acrylic acid) (PAAc) hydrogel prepared by gamma-ray irradiation was investigated. Zinc chloride powder with different concentrations was dissolved in the PAAc solution, and it was crosslinked with gamma-ray irradiation. The effects of various parameters such as zinc ion concentration and irradiation doses on characteristics of the hydrogel formed were investigated in detail for obtaining an antibacterial wound dressing. In addition, the gel content, pH-sensitive (pH 4 or 7) swelling ratio, and UV–vis absorption spectra of the zinc particles in the hydrogels were characterized. Moreover, antibacterial properties of these new materials against Staphylococcus aureus and Escherichia coli strains were observed on solid growth media. The antibacterial tests indicated that the zinc chloride containing PAAc hydrogels have good antibacterial activity. - Highlights: • The characterization of zinc chloride containing PAA hydrogel was investigated. • The gel content increased with an increase in absorbed dose up to 75 kGy. • Finally, the zinc chloride based hydrogels have an antibacterial activity

  12. A Thermo-Hygro-Coupled Model for Chloride Penetration in Concrete Structures

    Directory of Open Access Journals (Sweden)

    Nattapong Damrongwiriyanupap

    2015-01-01

    Full Text Available Corrosion damage due to chloride attack is one of the most concerning issues for long term durability of reinforced concrete structures. By developing the reliable mathematical model of chloride penetration into concrete structures, it can help structural engineers and management agencies with predicting the service life of reinforced concrete structures in order to effectively schedule the maintenance, repair, and rehabilitation program. This paper presents a theoretical and computational model for chloride diffusion in concrete structures. The governing equations are taking into account the coupled transport process of chloride ions, moisture, and temperature. This represents the actual condition of concrete structures which are always found in nonsaturated and nonisothermal conditions. The fully coupled effects among chloride, moisture, and heat diffusion are considered and included in the model. The coupling parameters evaluated based on the available material models and test data are proposed and explicitly incorporated in the governing equations. The numerical analysis of coupled transport equations is performed using the finite element method. The model is validated by comparing the numerical results against the available experimental data and a good agreement is observed.

  13. Inhibition of herpes simplex virus type 1 entry by chloride channel inhibitors tamoxifen and NPPB

    International Nuclear Information System (INIS)

    Highlights: • We analyze the anti-HSV potential of chloride channel inhibitors. • Tamoxifen and NPPB show anti-HSV-1 and anti-ACV-resistant HSV-1 activities. • HSV-1 infection induces intracellular chloride concentration increasing. • Tamoxifen and NPPB inhibit HSV-1 early infection. • Tamoxifen and NPPB prevent the fusion process of HSV-1. - Abstract: Herpes simplex virus type 1 (HSV-1) infection is very common worldwide and can cause significant health problems from periodic skin and corneal lesions to encephalitis. Appearance of drug-resistant viruses in clinical therapy has made exploring novel antiviral agents emergent. Here we show that chloride channel inhibitors, including tamoxifen and 5-nitro-2-(3-phenyl-propylamino) benzoic acid (NPPB), exhibited extensive antiviral activities toward HSV-1 and ACV-resistant HSV viruses. HSV-1 infection induced chloride ion influx while treatment with inhibitors reduced the increase of intracellular chloride ion concentration. Pretreatment or treatment of inhibitors at different time points during HSV-1 infection all suppressed viral RNA synthesis, protein expression and virus production. More detailed studies demonstrated that tamoxifen and NPPB acted as potent inhibitors of HSV-1 early entry step by preventing viral binding, penetration and nuclear translocation. Specifically the compounds appeared to affect viral fusion process by inhibiting virus binding to lipid rafts and interrupting calcium homeostasis. Taken together, the observation that tamoxifen and NPPB can block viral entry suggests a stronger potential for these compounds as well as other ion channel inhibitors in antiviral therapy against HSV-1, especially the compound tamoxifen is an immediately actionable drug that can be reused for treatment of HSV-1 infections

  14. Inhibition of herpes simplex virus type 1 entry by chloride channel inhibitors tamoxifen and NPPB

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Kai [Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Jinan University, Guangzhou (China); College of Life Science and Technology, Jinan University, Guangzhou (China); Chen, Maoyun [Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Jinan University, Guangzhou (China); College of pharmacy, Jinan University, Guangzhou (China); Xiang, Yangfei; Ma, Kaiqi [Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Jinan University, Guangzhou (China); Jin, Fujun [Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Jinan University, Guangzhou (China); College of pharmacy, Jinan University, Guangzhou (China); Wang, Xiao [School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006 (China); Wang, Xiaoyan; Wang, Shaoxiang [Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Jinan University, Guangzhou (China); Wang, Yifei, E-mail: twang-yf@163.com [Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Jinan University, Guangzhou (China)

    2014-04-18

    Highlights: • We analyze the anti-HSV potential of chloride channel inhibitors. • Tamoxifen and NPPB show anti-HSV-1 and anti-ACV-resistant HSV-1 activities. • HSV-1 infection induces intracellular chloride concentration increasing. • Tamoxifen and NPPB inhibit HSV-1 early infection. • Tamoxifen and NPPB prevent the fusion process of HSV-1. - Abstract: Herpes simplex virus type 1 (HSV-1) infection is very common worldwide and can cause significant health problems from periodic skin and corneal lesions to encephalitis. Appearance of drug-resistant viruses in clinical therapy has made exploring novel antiviral agents emergent. Here we show that chloride channel inhibitors, including tamoxifen and 5-nitro-2-(3-phenyl-propylamino) benzoic acid (NPPB), exhibited extensive antiviral activities toward HSV-1 and ACV-resistant HSV viruses. HSV-1 infection induced chloride ion influx while treatment with inhibitors reduced the increase of intracellular chloride ion concentration. Pretreatment or treatment of inhibitors at different time points during HSV-1 infection all suppressed viral RNA synthesis, protein expression and virus production. More detailed studies demonstrated that tamoxifen and NPPB acted as potent inhibitors of HSV-1 early entry step by preventing viral binding, penetration and nuclear translocation. Specifically the compounds appeared to affect viral fusion process by inhibiting virus binding to lipid rafts and interrupting calcium homeostasis. Taken together, the observation that tamoxifen and NPPB can block viral entry suggests a stronger potential for these compounds as well as other ion channel inhibitors in antiviral therapy against HSV-1, especially the compound tamoxifen is an immediately actionable drug that can be reused for treatment of HSV-1 infections.

  15. Inhibition of nitrite-induced toxicity in channel catfish by calcium chloride and sodium chloride

    Science.gov (United States)

    Tommasso J.R., Wright, M. I.; Simco, B.A.; Davis, K.B.

    1980-01-01

    Environmental chloride has been shown to inhibit methemoglobin formation in fish, thereby offering a protective effect against nitrite toxicity. Channel catfish (Ictalurus punctatus) were simultaneously exposed to various environmental nitrite and chloride levels (as either CaCl2 or NaCl) in dechlorinated tap water (40 mg/L total hardness, 47 mg/L alkalinity, 4 mg/L chloride, pH = 6.9-7.1, and temperature 21-24°C). Methemoglobin levels in fish simultaneously exposed to 2.5 mg/L nitrite and up to 30 mg/L chloride as either CaCl2 or NaCl were similar but significantly lower than in unprotected fish. Exposure to 10 mg/L nitrite and 60 mg/L chloride resulted in methemoglobin levels similar to those of the controls; most unprotected fish died. Fish exposed to 10 mg/L nitrite had significantly lower methemoglobin levels when protected with 15.0 mg/L chloride as CaCl2 than with NaCl. Fish exposed to nitrite in the presence of 60 mg/L chloride (as either CaCl2 or NaCl) had similar 24-h LC50 values that were significantly elevated above those obtained in the absence of chloride. Calcium had little effect on tolerance to nitrite toxicity in channel catfish in contrast to its large effect reported in steelhead trout (Salmo gairdneri).

  16. Amine and Titanium (IV Chloride, Boron (III Chloride or Zirconium (IV Chloride-Promoted Baylis-Hillman Reactions

    Directory of Open Access Journals (Sweden)

    Shi-Cong Cui

    2001-10-01

    Full Text Available The Baylis-Hillman reactions of various aryl aldehydes with methyl vinyl ketone at temperatures below -20oC using Lewis acids such as titanium (IV chloride, boron (III chloride or zirconium (IV chloride in the presence of a catalytic amount of selected amines used as a Lewis bases afford the chlorinated compounds 1 as the major product in very high yields. Acrylonitrile can also undergo the same reaction to give the corresponding chlorinated product in moderate yield. A plausible reaction mechanism is proposed. However, if the reaction was carried out at room temperature (ca. 20oC, then the Z-configuration of the elimination product 3, derived from 1, was formed as the major product.

  17. Corrosion of LY12 aluminum alloy in sodium chloride solution

    Institute of Scientific and Technical Information of China (English)

    程英亮; 张昭; 曹发和; 李劲风; 张鉴清; 王建明; 曹楚南

    2003-01-01

    The corrosion behavior of LY12 alloy in sodium chloride solution and its electrochemical noise were reported. The development of the micro-pits on the alloy surface was monitored by scanning electron microscopy, scanning tunneling microscopy, and electrochemical noise method. All the measurements show that the corrosion of LY12 alloy can be divided into two stages: a very reactive initial stage and a relative constant stable stage. The initial stage is corresponded to the adsorption of Cl ions and its reaction with the oxide film and the dissolution of Mg containing particles. The stable stage is corresponded to the development of the micro-pits by the galvanic attack formed by Al-Fe-Cu-Mn containing particles and the matrix. The initial stage lasts about 2-3 h while the stable stage dominates the whole corrosion process.

  18. Extraction of zirconium and hafnium thiocyanates by CH3COCH2CH.(CH3)2-HSCN solvent from chloride medium

    International Nuclear Information System (INIS)

    A zirconium-hafnium separation process for application in nuclear industry is presented. The extraction of zirconium and hafnium thiocyanates in chloride medium by hexone-HSCN solvent was studied. The extraction process was developed, varying the parameters, such as, concentrations of the metals, the thiocyanate ion, the sulphate ion and free acidity in aqueous phase. (Author)

  19. Sulphate analysis in uranium leach iron(III) chloride solutions by inductively coupled argon plasma spectrometry

    International Nuclear Information System (INIS)

    Inductively coupled Argon Plasma Spectrometry is used for the indirect determination of sulphate in iron(III) chloride leach solution of Elliot Lake uranium ores via addition of a known amount of barium ions and analyzing for excess of barium. The ore contains ∼ 7 wt% pyrite, FeS2, as the major mineral which oxidizes to generate sulphate during leaching with Fe(III). The effects of pH, the concentrations of Fe(III) and chloride ions and for presence of ethanol in the test samples on the accuracy of analysis are studied. It is found that unlike the Rhodizonate method, removal of iron(III) from or addition of ethanol to the test sample prior to analysis are not required. Linear calibration curves are obtained. (author)

  20. Structure transitions between copper-sulphate and copper-chloride UPD phases on Au(111)

    Indian Academy of Sciences (India)

    Ilya V Pobelov; Gábor Nagy; Thomas Wandlowski

    2009-09-01

    Structure transitions between copper UPD adlayers on Au(111)-(1 × 1) in sulfuric acid and chloride containing electrolyte were investigated by in situ scanning tunnelling microscopy. We demonstrate that co-adsorbed sulphate ions in the (√3 × √3)R30° UPD adlayer are replaced by chloride ions and, depending on the halide coverage, a commensurate (2 × 2) or a slightly distorted (5 × 5)-like Cu-Cl UPD adlayer are formed. The stability ranges of these phases are controlled both by the electrode potential and the Cl- concentration. Phase transitions between the three UPD phases were monitored by time-resolved in situ STM. The observed structure details were attributed to mechanisms based on two-dimensional nucleation and growth processes.

  1. Growth responses of the halophyte selicornia herbacea l. (=S. europaea) under different treatments of sodium chloride and fertilizers

    International Nuclear Information System (INIS)

    The growth respose of the halophyte Salicornia herbacea was examined under different treatments using sodium chloride, nitrogenous and phosphorous sources and irrigation in the field. The data revealed that the growth. in terms of dry weight and shoot length, of the plants was inhanced by sodium chloride and maximum growth was obtained at 1000 mol concentration. Plant growth was retarded under other treatments. However, growth was greatly reduced in nitrogen (urea) application. The major ions constituents of shoots was Na and Cl. The levels of these ions were highly affected by the treatments.Highest levels of Na and CI was found at 1000 mol sodium chloride and lowest at irrigated plants. (authors). 13 refs., 4 figs., 3 tabs

  2. Experimental Investigation on Pore Structure Characterization of Concrete Exposed to Water and Chlorides

    OpenAIRE

    Jun Liu; Kaifeng Tang; Qiwen Qiu; Dong Pan; Zongru Lei; Feng Xing

    2014-01-01

    In this paper, the pore structure characterization of concrete exposed to deionised water and 5% NaCl solution was evaluated using mercury intrusion porosity (MIP), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The effects of calcium leaching, fly ash incorporation, and chloride ions on the evolution of pore structure characteristics were investigated. The results demonstrate that: (i) in ordinary concrete without any fly ash, the leaching effect of the cement products is mo...

  3. ARE MODELS OF ANION HYDRATION OVERBOUND ? THE SOLVATION OF THE ELECTRON AND CHLORIDE ANION COMPARED

    OpenAIRE

    Sprik, M.

    1991-01-01

    By means of a fully polarizable model for the chloride ion-water interaction we show that the modelling of anion solvation suffers from a similar inconsistency as the current electron-solvent potentials. Either the bulk hydration enthalpies are correct with the first hydration shell overbound, or the potential is adapted to describe the local environment of the solute at the expense of a major loss of solvation enthalpy. It is argued that boundary effects in the simulation are at least partly...

  4. Lysozyme net charge and ion binding in concentrated aqueous electrolyte solutions

    Energy Technology Data Exchange (ETDEWEB)

    Kuehner, Daniel E.; Engmann, Jan; Fergg, Florian; Wernick, Meredith; Blanch, Harvey W. [Univ. of California, Berkeley, CA (United States). Dept. of Chemical Engineering; Prausnitz, John M. [Univ. of California, Berkeley, CA (United States). Dept. of Chemical Engineering

    1999-02-01

    Hydrogen-ion titrations were conducted for hen-egg-white lysozyme in solutions of potassium chloride over the range pH 2.5--11.5 and for ionic strengths to 2.0 M. The dependence of lysozyme`s net proton charge, z{sub p}, on pH and ionic strength in potassium chloride solution is measured. From the ionic-strength dependence of z{sub p}, interactions of lysozyme with potassium and chloride ions are calculated using the molecular-thermodynamic theory of Fraaije and Lyklema. Lysozyme interacts preferentially with up to 12 chloride ions at pH 2.5. The observed dependence of ion-protein interactions on pH and ionic strength is explained in terms of electric-double-layer theory. New experimental pK{sub a} data are reported for 11 amino acids in potassium chloride solutions of ionic strength to 3.0 M.

  5. Combining sulfate electrowinning with chloride leaching

    Science.gov (United States)

    Fletcher, A. W.; Sudderth, R. B.; Olafson, S. M.

    1991-08-01

    Although the chloride leaching of copper sulfide concentrates has proved highly efficient, electrowinning from chloride solutions presents many difficulties, notably in cell design and the handling of the powder product. Sulfate electrowinning,on the other hand, continues to improve and has played a significant part in the widespread adoption of the solvent extraction-electrowinning process for copper recovery from low-grade ores. It has been found that the two steps can be combined by introducing a novel solvent extraction process after chloride leaching. This article presents the results of laboratory tests to prove the feasibility of this approach and discusses how it can be integrated into a commercially viable flow sheet.

  6. Phase and extraction equilibria in water-polyethyleneglycol ethers of monoethanolamides of synthetic fatty acid-ammonium chloride systems

    Science.gov (United States)

    Lesnov, A. E.; Golovkina, A. V.; Kudryashova, O. S.; Denisova, S. A.

    2016-08-01

    Phase equilibria in layering systems of water, polyethyleneglycol ethers of monoethanolamides of synthetic fatty acids (SFAs) (synthamide-5), and ammonium chloride are studied. The possibility of using such systems for the liquid extraction of metal ions is evaluated. The effect the nature of salting-out agents has on the processes of segregation of the systems has been considered.

  7. Functionalyzed Polyampholytes on the Basis of Copolymers of N,N-Diallyl-N,N-dimethylammonium Chloride and Maleic Acid

    DEFF Research Database (Denmark)

    Vlasov, Petr; Chernyy, Sergey; Domnina, Nina

    2010-01-01

    Polyampholytes were prepared by radical copolymerization of N,N-diallyl-N,N-dimethylammonium chloride and maleic acid. The esterification and subsequent hydrazinolysis permitted to introduce hydrazide groups capable of formation of the coordination bond with copper ions. The formation of complex ...

  8. Interlayer interaction in Ca-Fe layered double hydroxides intercalated with nitrate and chloride species

    Science.gov (United States)

    Al-Jaberi, Muayad; Naille, Sébastien; Dossot, Manuel; Ruby, Christian

    2015-12-01

    Ca-Fe layered double hydroxide (LDH) intercalated with chloride and nitrate ions has been synthesized with varying CaII:FeIII molar ratios of the initial solution. Phase pure LDH is observed with CaII:FeIII molar ratio of 2:1 and a mixture of LDH and Ca(OH)2 is formed for CaII:FeIII molar ratios higher than 2:1. Vibrational spectroscopies (Raman and IR) were used successfully to understand the interaction between the cationic and anionic sheets. The Raman bands positions at lower frequencies (150-600 cm-1) are intimately correlated to the nature of the divalent and trivalent ions but also to the nature of the anions. Indeed, a shift of ˜9 cm-1 is observed for the Raman double bands situated in the 300-400 cm-1 region when comparing Raman spectra of CaFe-LDH containing either nitrate or chloride ions. Two types of nitrate environments are observed namely free (non-hydrogen bonded) nitrate and nitrate hydrogen bonded to the interlayer water or to the 'brucite-like' hydroxyl surface. Multiple types of water structure are observed and would result from different hydrogen bond structures. Water bending modes are identified at 1645 cm-1 greater than the one observed for LDH intercalated with chloride anions (1618 cm-1), indicating that the water is strongly hydrogen bonded to the nitrate anions.

  9. Comparison of Inactivation and Unfolding of Calf Intestinal Alkaline Phosphatase in Guanidinium Chloride Solution

    Institute of Scientific and Technical Information of China (English)

    张英侠; 闫淑莲; 刘永利; 席宏伟; 周海梦

    2002-01-01

    The changes in activity and unfolding of calf intestinal alkaline phosphatase (CIP) during denaturation in guanidinium chloride solutions of different concentrations were investigated using ultraviolet difference absorption spectra and fluorescence emission spectra. Unfolding and inactivation rate constants were measured and compared. The inactivation course is much faster than that of unfolding, which suggests that the active site of CIP containing two zinc ions and one magnesium ion is situated in a limited and flexible region of the enzyme molecule, which is more fragile to the denaturant than the protein as a whole.

  10. Differentiation of energy expenditure of membrane electrochemical utilization of lithium chloride in polymeric fibers production

    International Nuclear Information System (INIS)

    Electric power consumption for preparation of lithium hydroxide aqueous solution for regeneration stage in production of polymer fibers in a wide range of catholyte volumetric consumption has been calculated by the data of laboratory experiments, the results are presented. Energy consumption for lithium ions transfer through the Nafion membrane has been separated. It is shown that under stationary conditions of lithium chloride aqueous solution electrolysis and at current loading on the membrane approximately up to 1 kA x m-2 the drifting lithium ions can not upset preliminary flooding of the membrane. 10 refs.; 3 figs.; 1 tab

  11. Alkali metal and ammonium chlorides in water and heavy water (binary systems)

    CERN Document Server

    Cohen-Adad, R

    1991-01-01

    This volume surveys the data available in the literature for solid-fluid solubility equilibria plus selected solid-liquid-vapour equilibria, for binary systems containing alkali and ammonium chlorides in water or heavy water. Solubilities covered are lithium chloride, sodium chloride, potassium chloride, rubidium chloride, caesium chloride and ammonium chloride in water and heavy water.

  12. Method for preparation of melts of alkali metal chlorides with highly volatile polyvalent metal chlorides

    International Nuclear Information System (INIS)

    A method for production of alkali metal (Cs, Rb, K) chloride melts with highly volatile polyvalent metal chlorides is suggested. The method consists, in saturation of alkali metal chlorides, preheated to the melting point, by volatile component vapours (titanium tetrachloride, molybdenum or tantalum pentachloride) in proportion, corresponding to the composition reguired. The saturation is realized in an evacuated vessel with two heating areas for 1-1.5 h. After gradual levelling of temperature in both areas the product is rapidly cooled. 1 fig.; 1 tab

  13. Electrochemical extraction of samarium from molten chlorides in pyrochemical processes

    Energy Technology Data Exchange (ETDEWEB)

    Castrillejo, Y., E-mail: ycastril@qa.uva.es [QUIANE/Dept Quimica Analitica, F. de Ciencias, Universidad de Valladolid, Prado de la Magdalena s/n, 47005 Valladolid (Spain); Fernandez, P. [QUIANE/Dept Quimica Analitica, F. de Ciencias, Universidad de Valladolid, Prado de la Magdalena s/n, 47005 Valladolid (Spain); Medina, J. [Dept Fisica Materia Condensada Cristalografia y Mineralogia, F. de Ciencias, Universidad de Valladolid, Prado de la Magdalena s/n, 47005 Valladolid (Spain); Hernandez, P. [Centro de Investigaciones Quimicas, Universidad Autonoma del Estado de Hidalgo, Carr. Pachuca-Tulancingo Km. 4.5, C.P. 42076 Pachuca, Hidalgo (Mexico); Barrado, E. [QUIANE/Dept Quimica Analitica, F. de Ciencias, Universidad de Valladolid, Prado de la Magdalena s/n, 47005 Valladolid (Spain)

    2011-10-01

    This work concerns the electrochemical extraction of samarium from molten chlorides. In this way, the electrochemical behaviour of samarium ions has been investigated in the eutectic LiCl-KCl at the surface of tungsten, aluminium and aluminium coated tungsten electrodes. On a W inert electrode the electro-reduction of Sm(III) takes place in only one soluble-soluble electrochemical step Sm(III)/Sm(II). The electrochemical system Sm(II)/Sm(0) has not been observed within the electrochemical window, because of the prior reduction of Li(I) ions from the solvent, which inhibits the electro-extraction of Sm species from the salt on such a substrate. Sm metal in contact with the melt react to give Li(0) according to the reaction: Sm(0) + 2Li(I) {r_reversible} Sm(II) + 2Li(0). On the contrary, on reactive Al electrodes the electrochemical system Sm(II)/Sm(0) was observed within the electroactive range. The potential shift of the redox couple is caused by the decrease of Sm activity in the metal phase due to the formation of Sm-Al alloys at the interface. The formation mechanism of the intermetallic compounds was studied in a melt containing: (i) both Sm(III) and Al(III) ions, using W and Al coated tungsten electrodes, and (ii) Sm(III) ions using an Al electrode. Analysis of the samples after potentiostatic electrolysis by X-ray diffraction and scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS), allowed the identification of Al{sub 3}Sm and Al{sub 2}Sm.

  14. Fluid shear stress enhances the cell volume decrease of osteoblast cells by increasing the expression of the ClC-3 chloride channel

    OpenAIRE

    Liu, Li; Cai, Siyi; Qiu, Guixing; Lin, Jin

    2016-01-01

    ClC-3 is a volume-sensitive chloride channel that is responsible for cell volume adjustment and regulatory cell volume decrease (RVD). In order to evaluate the effects of fluid shear stress (FSS) stimulation on the osteoblast ClC-3 chloride channel, MC3T3-E1 cells were stimulated by FSS in the experimental group. Fluorescence quantitative polymerase chain reaction was used to detect changes in ClC-3 mRNA expression, the chloride ion fluorescent probe N-(ethoxycarbonylmethyl)-6-methoxyquinolin...

  15. Oral cadmium chloride intoxication in mice

    DEFF Research Database (Denmark)

    Andersen, O; Nielsen, J B; Svendsen, P

    1988-01-01

    Diethyldithiocarbamate (DDC) is known to alleviate acute toxicity due to injection of cadmium salts. However, when cadmium chloride was administered by the oral route, DDC enhanced rather than alleviated the acute toxicity; both oral and intraperitoneal (i.p.) administration of DDC had this effec...

  16. Liquid crystalline critical dynamics in decylammonium chloride

    CERN Document Server

    Lee, K W; Lee, C E; Kang, K H; Rhee, C; Kang, J K

    1999-01-01

    Collective chain dynamics and phase transitions in a model biomembrane, decylammonium chloride (C sub 1 sub 0 H sub 2 sub 1 NH sub 3 Cl), were studied by means of proton nuclear magnetic resonance. Our measurements sensitively reflect the critical dynamics associated with the smectic C to smectic A transition of the lipid bilayer.

  17. Liquid crystalline critical dynamics in decylammonium chloride

    International Nuclear Information System (INIS)

    Collective chain dynamics and phase transitions in a model biomembrane, decylammonium chloride (C10H21NH3Cl), were studied by means of proton nuclear magnetic resonance. Our measurements sensitively reflect the critical dynamics associated with the smectic C to smectic A transition of the lipid bilayer

  18. Chloride diffusion in partially saturated cementitious material

    DEFF Research Database (Denmark)

    Nielsen, Erik Pram; Geiker, Mette Rica

    2003-01-01

    The paper proposes a combined application of composite theory and Powers' model for microstructural development for the estimation of the diffusion coefficient as a function of the moisture content of a defect-free cementitious material. Measurements of chloride diffusion in mortar samples (440 kg...

  19. 75 FR 19657 - Barium Chloride From China

    Science.gov (United States)

    2010-04-15

    ... Commission found that the domestic interested party group response to its notice of institution (74 FR 31757... COMMISSION Barium Chloride From China AGENCY: United States International Trade Commission. ACTION: Notice of Commission determination to conduct a full five-year review concerning the antidumping duty order on...

  20. 75 FR 20625 - Barium Chloride From China

    Science.gov (United States)

    2010-04-20

    ... established a schedule for the conduct of this review (74 FR 62587, November 30, 2010). Subsequently, counsel... From the Federal Register Online via the Government Publishing Office INTERNATIONAL TRADE COMMISSION Barium Chloride From China AGENCY: United States International Trade Commission. ACTION:...

  1. Chloride concentration affects soil microbial community

    Czech Academy of Sciences Publication Activity Database

    Gryndler, Milan; Rohlenová, Jana; Kopecký, Jan; Matucha, Miroslav

    2008-01-01

    Roč. 71, č. 7 (2008), s. 1401-1408. ISSN 0045-6535 R&D Projects: GA ČR GA526/05/0636 Institutional research plan: CEZ:AV0Z50200510; CEZ:AV0Z50380511 Keywords : soil chloride * terminal restriction fragments * soil microorganisms Subject RIV: EE - Microbiology, Virology Impact factor: 3.054, year: 2008

  2. Determination of chloride in uranium solutions

    Energy Technology Data Exchange (ETDEWEB)

    Danse, A.; Stoch, H.; Steele, T.W.

    1967-05-15

    Thiocyanate is first removed by precipitation with a small excess of a copper solution, and the cations are removed by passing the filtrate through a cation-exchange resin. The chloride is determined in the eluate by a potentiometric titration in which silver nitrate solution is used.

  3. Polyvinyl chloride filled with bismuth oxychloride powder

    Czech Academy of Sciences Publication Activity Database

    Polášková, M.; Sedláček, T.; Kharlamov, Alexander; Pivokonský, Radek; Saha, P.

    Larnaca : Polymer Processing Society, 2009, s. 242. [Polymer Processing Society Europe/Africa Regional Meeting. Larnaca (GR), 18.10.2009-21.10.2009] Institutional research plan: CEZ:AV0Z20600510 Keywords : olyvinyl chloride * bismuth oxychloride * radiopaque agents Subject RIV: BK - Fluid Dynamics

  4. Binary nucleation of water and sodium chloride

    Czech Academy of Sciences Publication Activity Database

    Němec, Tomáš; Maršík, František; Palmer, A.

    2006-01-01

    Roč. 124, č. 4 (2006), 0445091-0445096. ISSN 0021-9606 R&D Projects: GA ČR(CZ) GA101/05/2536 Institutional research plan: CEZ:AV0Z20760514 Keywords : binary nucleation * sodium chloride * water Subject RIV: BJ - Thermodynamics Impact factor: 3.166, year: 2006

  5. 21 CFR 184.1446 - Manganese chloride.

    Science.gov (United States)

    2010-04-01

    ..., and crystallized. (b) The ingredient meets the specifications of the Food Chemicals Codex, 3d Ed... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Manganese chloride. 184.1446 Section 184.1446 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD...

  6. Ion Selectivity Mechanism in a Bacterial Pentameric Ligand-Gated Ion Channel

    International Nuclear Information System (INIS)

    The proton-gated ion channel from Gloeobacter violaceus (GLIC) is a prokaryotic homolog of the eukaryotic nicotinic acetylcholine receptor that responds to the binding of neurotransmitter acetylcholine and mediates fast signal transmission. Recent emergence of a high-resolution crystal structure of GLIC captured in a potentially open state allowed detailed, atomic-level insight into ion conduction and selectivity mechanisms in these channels. Herein, we have examined the barriers to ion conduction and origins of ion selectivity in the GLIC channel by the construction of potential-of-mean-force profiles for sodium and chloride ions inside the transmembrane region. Our calculations reveal that the GLIC channel is open for a sodium ion to transport, but presents a 11 kcal/mol free energy barrier for a chloride ion. Our collective findings identify three distinct contributions to the observed preference for the permeant ions. First, there is a substantial contribution due to a ring of negatively charged glutamate residues (E-2 ) at the narrow intracellular end of the channel. The negative electrostatics of this region and the ability of the glutamate side chains to directly bind cations would strongly favor the passage of sodium ions while hindering translocation of chloride ions. Second, our results imply a significant hydrophobic contribution to selectivity linked to differences in the desolvation penalty for the sodium versus chloride ions in the central hydrophobic region of the pore. This hydrophobic contribution is evidenced by the large free energy barriers experienced by Cl in the middle of the pore for both GLIC and the E-2 A mutant. Finally, there is a distinct contribution arising from the overall negative electrostatics of the channel.

  7. Viscosity and density tables of sodium chloride solutions

    Energy Technology Data Exchange (ETDEWEB)

    Fair, J.A.; Ozbek, H. (comps.)

    1977-04-01

    A file is presented containing tabulated data extracted from the scientific literature on the density and viscosity of aqueous sodium chloride solutions. Also included is a bibliography of the properties of aqueous sodium chloride solutions. (MHR)

  8. Electrochemistry of Iodide, Iodine, and Iodine Monochloride in Chloride Containing Nonhaloaluminate Ionic Liquids.

    Science.gov (United States)

    Bentley, Cameron L; Bond, Alan M; Hollenkamp, Anthony F; Mahon, Peter J; Zhang, Jie

    2016-02-01

    The electrochemical behavior of iodine remains a contemporary research interest due to the integral role of the I(-)/I3(-) couple in dye-sensitized solar cell technology. The neutral (I2) and positive (I(+)) oxidation states of iodine are known to be strongly electrophilic, and thus the I(-)/I2/I(+) redox processes are sensitive to the presence of nucleophilic chloride or bromide, which are both commonly present as impurities in nonhaloaluminate room temperature ionic liquids (ILs). In this study, the electrochemistry of I(-), I2, and ICl has been investigated by cyclic voltammetry at a platinum macrodisk electrode in a binary IL mixture composed of 1-butyl-3-methylimidazolium chloride ([C4mim]Cl) and 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([C2mim][NTf2]). In the absence of chloride (e.g., in neat [C2mim][NTf2]), I(-) is oxidized in an overall one electron per iodide ion process to I2 via an I3(-) intermediate, giving rise to two resolved I(-)/I3(-) and I3(-)/I2 processes, as per previous reports. In the presence of low concentrations of chloride ([Cl(-)] and [I(-)] are both complex anion [ICl2](-), in an overall two electron per iodide ion process. In the presence of a large excess of Cl(-) ([I(-)] ≈ 10 mM and [Cl(-)] ≈ 3.7 M), I(-) is oxidized in an overall two electron per iodide ion process to [ICl2](-) via an [I2Cl](-) intermediate (confirmed by investigating the voltammetric response of ICl and I2 under these conditions). In summary, the I(-)/I2/I(+) processes in nonhaloaluminate ILs involve a complicated interplay between multiple electron transfer pathways and homogeneous chemical reactions which may not be at equilibrium on the voltammetric time scale. PMID:26708364

  9. Chloride secretagogues stimulate inositol phosphate formation in shark rectal gland tubules cultured in suspension

    Energy Technology Data Exchange (ETDEWEB)

    Ecay, T.W.; Valentich, J.D. (Univ. of Texas Medical School, Houston (USA))

    1991-03-01

    Neuroendocrine activation of transepithelial chloride secretion by shark rectal gland cells is associated with increases in cellular cAMP, cGMP, and free calcium concentrations. We report here on the effects of several chloride secretagogues on inositol phosphate formation in cultured rectal gland tubules. Vasoactive intestinal peptide (VIP), atriopeptin (AP), and ionomycin increase the total inositol phosphate levels of cultured tubules, as measured by ion exchange chromatography. Forskolin, a potent chloride secretagogue, has no effect on inositol phosphate formation. The uptake of {sup 3}H-myo-inositol into phospholipids is very slow, preventing the detection of increased levels of inositol trisphosphate. However, significant increases in inositol monophosphate (IP1) and inositol biphosphate (IP2) were measured. The time course of VIP- and AP-stimulated IP1 and IP2 formation is similar to the effects of these agents on the short-circuit current responses of rectal gland monolayer cultures. In addition, aluminum fluoride, an artificial activator of guanine nucleotide-binding proteins, stimulates IP1 and IP2 formation. We conclude that rectal gland cells contain VIP and AP receptors coupled to the activation of phospholipase C. Coupling may be mediated by G-proteins. Receptor-stimulated increases in inositol phospholipid metabolism is one mechanism leading to increased intracellular free calcium concentrations, an important regulatory event in the activation of transepithelial chloride secretion by shark rectal gland epithelial cells.

  10. Chloride adsorption by calcined layered double hydroxides in hardened Portland cement paste

    KAUST Repository

    Yoon, Seyoon

    2014-06-01

    This study investigated the feasibility of using calcined layered double hydroxides (CLDHs) to prevent chloride-induced deterioration in reinforced concrete. CLDHs not only adsorbed chloride ions in aqueous solution with a memory effect but also had a much higher binding capacity than the original layered double hydroxides (LDHs) in the cement matrix. We investigated this adsorption in hardened cement paste in batch cultures to determine adsorption isotherms. The measured and theoretical binding capacities (153 mg g -1 and 257 mg g-1, respectively) of the CLDHs were comparable to the theoretical capacity of Friedel\\'s salt (2 mol mol-1 or 121 mg g-1), which belongs to the LDH family among cementitious phases. We simulated chloride adsorption by CLDHs through the cement matrix using the Fickian model and compared the simulation result to the X-ray fluorescence (XRF) chlorine map. Based on our results, it is proposed that the adsorption process is governed by the chloride transport through the cement matrix; this process differs from that in an aqueous solution. X-ray diffraction (XRD) analysis showed that the CLDH rebuilds the layered structure in a cementitious environment, thereby demonstrating the feasibility of applying CLDHs to the cement and concrete industries. © 2014 Published by Elsevier B.V. All rights reserved.

  11. Inclusions of chlorides in natural diamonds from Siberia

    Science.gov (United States)

    Titkov, Sergey; Ryabchikov, Igor; Pomazansky, Bogdan; Magazina, Larisa

    2010-05-01

    .6 wt% Si, 23,2 wt% Cl, 39.5 wt% O. The majority of oxygen may be due to the presence of water. The empty space of the cavity was filled with specific dendrites made up of K, Na, Cl, and O in variable proportions. In polycrystalline aggregate of diamond, empty cavity, about 70 m across, was found. Its walls were covered by elongated crystals of chlorides. They consisted of Na, K, Cl, and minor O, with Na sharply predominating over K. It appears that this inclusion contained a large amount of water and volatile components which were possibly lost. Cl-bearing fluids revealed in natural diamonds in the previous studies contained both K, Cl, water and variable amounts of Na, divalent ions (Ca, Mg, Fe, Ba), carbonate and silica. While it was suggested that pure Cl-brines may occurred in deep-seated diamond-forming system (Tomlinson et al., 2006; Klein-BenDavid et al., 2007). Our results indicate that evolution of diamond-forming systems actually may give birth to practically pure alkaline-chloride brines. These brines were trapped by growing diamonds as inclusions. Upon cooling, K-Na-chlorides crystallized from the brines. Water and volatile components of the system appeared to be removed under decrepitation of the inclusions. References Palyanov Y.N., Shatsky V.S., Sobolev N.V., Sokol A.G. (2007) Proc. Natl. Acad. Sci. U.S.A., 104, 9122-9127. Klein-BenDavid O., Izraeli E.S., Hauri E., Navon O. (2007) Geochim. Cosmochim. Acta, 71, 723-744. Tomlinson E.L., Jones A.P., Harris J.W. (2006) Earth Planet. Sci. Lett., 250, 581-595 Titkov S.V., Zudin N.G., Gorshkov A.I., Sivtsov A.V., Magazina L.O. (2003) Gems & Gemology, 39, 200-209.

  12. Contribution to the study of the mechanism of extraction of uranyl chloride by long chain aliphatic amines

    International Nuclear Information System (INIS)

    After having studied and developed the mechanisms which may 'a priori' explain the extraction process (co-ordination, ion association or intermediate mechanism), experience shows that ion association only should be taken into consideration. The structure of the organic complex of uranyl chloride has been defined on the basis of the study of the variation of the distribution coefficient of uranium between the two phases at the equilibrium as a function of successively the activity of Cl- ions in the aqueous phase, the concentration of amine salt in the organic phase and finally of the concentration of uranium in the aqueous phase. The plotting of the results in bi-logarithmic co-ordinates enables us to propose the following formula for the extracted compound: UO2Cl4--(NR3H+)2. The calculation of the equilibrium constant of formation of the organic compound of uranyl chloride has been possible in the case of diluted solutions of uranium only. (author)

  13. [Sweat chloride measurement using direct potentiometry: Spotchem(®) (Elitech-Arkray) evaluation and comparison with coulometry and conductivity].

    Science.gov (United States)

    Nguyen-Khoa, Thao; Borgard, Jean-Pierre; Miled, Ryad; Rota, Michèle

    2013-01-01

    Sweat chloride (Cl(-)) measurement is a key step for the diagnosis of cystic fibrosis. The coulometric technique is validated in this context by international guidelines. The aim of our study was to evaluate the assay for sweat Cl(-) ions using direct potentiometry on disposable cassette (Spotchem™ SE EL-1520, Elitech-Arkray) by comparing results to those obtained on the same sample, by coulometry (Chloride analyser Sherwood 926S, Dutscher). To complete our table of correspondence between the results of Cl(-) ions and sweat conductivity (Sweat Check™ 3100), conductivity has been also achieved for 99 of the 139 sweat samples studied. Linearity of each technique performed extends from 10 to 120 mmol/L. The coefficients of variation within and between runs are Spotchem] = 1.026 [Chloride analyser] + 1.8, r = 0.996. After correction with regression factors, only 6 pairs of values (4.6%) had a difference greater than ± 5 mmol/L). The results of conductivity measurement is strongly correlated with those of Cl(-) ions (r = 0.959 for Chloride analyser and 0.965 for Spotchem; p = 0.576) with a linear relationship between the decision thresholds from 30 to 60 mmol/L Cl(-). Sweat Cl(-) determinations using Spotchem™ analyser meet the criteria required by analytical recommendations. The technique is standardized, easy to perform and fast. Its good practicability makes the sweat test independent to operator and allows point-of care use. PMID:23906572

  14. Removal of iron contaminant from zirconium chloride solution

    International Nuclear Information System (INIS)

    This patent describes a process for eliminating iron contaminant from an aqueous zirconium chloride solution that has been contaminated with FeCl3 in a plant in which zirconium and hafnium chloride solutions are separated by a main MINK solvent extraction system and the FeCl3 is normally removed from the zirconium chloride solution by a secondary MINK solvent extraction system

  15. Kinetics of Vinyl Chloride Polymerization with Mixture of Initiators

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Kinetic models for the rate constants of vinyl chloride polymerization in the presence of initiator mixtures were proposed. They may be used to design the initiator recipes for the vinyl chloride polymerization with uniform rate at different temperatures at which various grades of poly(vinyl chloride) will be prepared.

  16. A cytochemical study of the "chloride cells" in the skin of a fresh-water teleost (Channa striata (Bl.) Channidae, Pisces).

    Science.gov (United States)

    Banerjee, T K; Mittal, A K

    1975-01-01

    The chloride cells in the skin of Channa striata have been described. The cytoplasm of these cells is filled with acidophilic, osmiophilic and sudanophilic granules. The sudanophila is due to phospholipids. These cells give positive reaction for chloride ions and exhibit the presence of neutral mucopolysaccharides. The cytoplasm of these cells is packed with numerous mitochondria and exhibit high succinic dehydrogenase activity which may provide the energy needed for the active transportation of ions. Alkaline phosphatase activity could not be demonstrated in these cells. The presence of chloride cells in comparatively large numbers in the regions where the epidermis is thin is correlated as an adaptation for the increased efficiency of these cells for the transportation of ions so as to maintain the osmotic concentration of its body fluid which is higher than that of the surrounding medium. PMID:127502

  17. (η6-Benzene)(2,2′-bipyridine-κ2 N,N′)chloridoruthenium(II) chloride methanol sesquisolvate

    OpenAIRE

    Polson, Matthew I. J.

    2007-01-01

    In the title compound, [RuCl(C6H6)(C10H8N2)]Cl·1.5CH4O, the RuII atom is in a distorted octahedral environment coordinated by an η6-benzene ring, a chelating 2,2′-bipyridine ligand and a chloride ion. The asymmetric unit is completed by a chloride anion and two methanol molecules, one of which is disordered about a centre of inversion with an occupancy of 0.5. It is an example of a ruthenium complex with a less sterically congested environment than in similar derivatives. In t...

  18. No salting-in of lysozyme chloride observed at low ionic strength over a large range of pH.

    OpenAIRE

    Retailleau, P; Riès-Kautt, M; Ducruix, A.

    1997-01-01

    Solubility of lysozyme chloride was determined in the absence of added salt and in the presence of 0.05-1.2 M NaCl, starting from isoionic lysozyme, which was then brought to pH values from 9 to 3 by addition of HCl. The main observation is the absence of a salting-in region whatever the pH studied. This is explained by a predominant electrostatic screening of the positively charged protein and/or by adsorption of chloride ions by the protein. The solubility increases with the protein net cha...

  19. Interaction and conformational changes of chromatin with divalent ions.

    OpenAIRE

    Borochov, N; Ausio, J; Eisenberg, H

    1984-01-01

    We have investigated the interaction of divalent ions with chromatin towards a closer understanding of the role of metal ions in the cell nucleus. The first row transition metal ion chlorides MnCl2, CoCl2, NiCl2 and CuCl2 lead to precipitation of chicken erythrocyte chromatin at a significantly lower concentration than the alkali earth metal chlorides MgCl2, CaCl2 and BaCl2. A similar distinction can be made for the compaction of chromatin to the "30 nm" solenoid higher order structure which ...

  20. Revised Model of Chloride Diffusion in Concrete Bridge by Considering Complex Action of Load and Chloride Binding Capacity

    OpenAIRE

    Xiang, Yiqiang; Guo, DongMei

    2014-01-01

    Coastal concrete bridges will suffer from deterioration of RC structural performance and resistance attenuation because of the chloride penetration and other environment factors. This article discusses current different chloride diffusion models and puts forward the revised model of chloride diffusion in concrete bridge by considering the complex action of load influence and chloride-binding capacity. Comparison of numerical predicted values and relative experimental tests show the presented ...

  1. Ion exchange purification of scandium

    Science.gov (United States)

    Herchenroeder, Laurie A.; Burkholder, Harvey R.

    1990-10-23

    An improvement in purification of scandium through ion exchange chromatography is disclosed in which the oxidation potential of the eluting solution is altered by the addition of potassium chlorate or ammonium chloride so that removal of contaminants is encouraged. The temperature, pH and concentration of the eluent HEDTA are controlled in order to maintain the scandium in the column while minimizing dilution of the scandium band. Recovery of scandium is improved by pumping dilute scandium over the column prior to stripping the scandium and precipitation. This eliminates the HEDTA ion and other monovalent cations contaminating the scandium band. This method maximizes recovery of scandium while maintaining purity.

  2. Mathematical model for chloride diffusion in reinforced concrete structures at Yucatan Peninsula, Mexico

    International Nuclear Information System (INIS)

    Corrosion of reinforcing steel can seriously limit the service life of concrete structures in marine applications. Chloride diffusion is one of the two major problems causing this phenomenon, increasing when the concrete is exposed to a marine environment in coastal areas. The service life of a structure may be divided into two general phases: an initiation period, in which the reinforcing steel surface is still passive as a result of the contact with a high pH medium the aggressive ions penetrate the concrete toward the reinforcing bar, and a propagation period that starts when the chloride ion contamination on the steel surface exceeds the critical threshold level for the passivity breakdown. The aim of this work is to examine the chloride diffusion at the initial period on a marine environment by considering the variability of the diffusion coefficients with inherent parameters of the concrete, exposed during a period of two years in Yucatan, Mexico. A model based on the second Fick's law is proposed the non-linearity of the problem is taken into account and a numerical procedure based on the finite difference methods is developed to solve the set of equations. Comparisons with experimental data are also carried out in order to show the reliability and the effectiveness of the proposed numerical model. (Author) 7 refs

  3. Molecular and evolutionary insights into the structural organization of cation chloride cotransporters

    Directory of Open Access Journals (Sweden)

    Anna-Maria Hartmann

    2015-01-01

    Full Text Available Cation chloride cotransporters (CCC play an essential role for neuronal chloride homeostasis. KCC2 is the principal Cl--extruder, whereas NKCC1 is the major Cl--uptake mechanism in many neurons. As a consequence, the action of the inhibitory neurotransmitters GABA and glycine strongly depend on the activity of these two transporters. Knowledge of the mechanisms involved in ion transport and regulation is thus of great importance to better understand normal and disturbed brain function. Although no overall 3-dimensional crystal structures are yet available, recent molecular and phylogenetic studies and modeling have provided new and exciting insights into structure-function relationships of cation chloride cotransporters. Here, we will summarize our current knowledge of the gross structural organization of the proteins, their functional domains, ion binding and translocation sites, and the established role of individual amino acids. A major focus will be laid on the delineation of shared and distinct organizational principles between KCC2 and NKCC1. Exploiting the richness of recently generated genome data across the tree of life, we will also explore the molecular evolution of these features.

  4. Crystal structure and functional characterization of a light-driven chloride pump having an NTQ motif

    Science.gov (United States)

    Kim, Kuglae; Kwon, Soon-Kyeong; Jun, Sung-Hoon; Cha, Jeong Seok; Kim, Hoyoung; Lee, Weontae; Kim, Jihyun F.; Cho, Hyun-Soo

    2016-01-01

    A novel light-driven chloride-pumping rhodopsin (ClR) containing an ‘NTQ motif' in its putative ion conduction pathway has been discovered and functionally characterized in a genomic analysis study of a marine bacterium. Here we report the crystal structure of ClR from the flavobacterium Nonlabens marinus S1-08T determined under two conditions at 2.0 and 1.56 Å resolutions. The structures reveal two chloride-binding sites, one around the protonated Schiff base and the other on a cytoplasmic loop. We identify a ‘3 omega motif' formed by three non-consecutive aromatic amino acids that is correlated with the B–C loop orientation. Detailed ClR structural analyses with functional studies in E. coli reveal the chloride ion transduction pathway. Our results help understand the molecular mechanism and physiological role of ClR and provide a structural basis for optogenetic applications. PMID:27554809

  5. STABILISATION OF SILTY CLAY SOIL USING CHLORIDE

    Directory of Open Access Journals (Sweden)

    TAMADHER T. ABOOD

    2007-04-01

    Full Text Available The object of this paper is to investigate the effect of adding different chloride compounds including (NaCl, MgCl2, CaCl2 on the engineering properties of silty clay soil. Various amounts of salts (2%, 4%, and 8% were added to the soil to study the effect of salts on the compaction characteristics, consistency limits and compressive strength. The main findings of this study were that the increase in the percentage of each of the chloride compounds increased the maximum dry density and decrease the optimum moisture content. The liquid limit, plastic limit and plasticity index decreased with the increase in salt content. The unconfinedcompressive strength increased as the salt content increased.

  6. BARRIER PROPERTIES OF VINYLIDENE CHLORIDE COPOLYMERS

    Institute of Scientific and Technical Information of China (English)

    LI Yuesheng; WENG Zhixue; HUANG Zhiming; PAN Zuren

    1996-01-01

    The permeability coefficients of a series of copolymers of vinylidene chloride (VDC)with methyl acrylate (MA), butyl acrylate (BA) or vinyl chloride (VC) (as comonomer)to oxygen and carbon dioxide have been measured at 1.0 MPa and 30℃, while those to water vapor have been measured at 30℃ and 100% relative humidity. All the copolymers are semicrystalline. VDC/MA copolymers have lower melting temperature compared with VDC/BA copolymers, while that melting temperature of VDC/VC copolymer is higher than that of VDC/acrylate copolymers with the same VDC content. The barrier property of the copolymers is predominantly controlled by crystallite, free volume fraction, and cohesive energy. The permeability coefficients of VDC/MA copolymers to oxygen, carbon dioxide, and water vapor were successfully correlated with the ratio of free volume to cohesive energy.

  7. Chloride migration in concrete with superabsorbent polymers

    DEFF Research Database (Denmark)

    Hasholt, Marianne Tange; Jensen, Ole Mejlhede

    2015-01-01

    Superabsorbent polymers (SAP) can be used as a means for internal curing of concrete. In the present study, the development of transport properties of concrete with SAP is investigated. The chloride migration coefficient according to NT BUILD 492 is used as a measure of this. Twenty concrete...... mixtures are tested 7, 14, and 28 days after casting. The development of degree of hydration is followed for 20 corresponding paste mixtures. Both when SAP is added with extra water to compensate the SAP water absorption in fresh concrete and without extra water, the internal curing water held by SAP may...... contribute to increase the degree of hydration. No matter if SAP is added with or without extra water, it appears that the so-called gel space ratio can be used as a key parameter to link age and mixture proportions (water-to-cement ratio and SAP dosage) to the resulting chloride migration coefficient; the...

  8. Acylation of Toluene with Isobutyryl Chloride

    Czech Academy of Sciences Publication Activity Database

    Čejka, Jiří; Klisáková, Jana; Žilková, Naděžda; Červený, L.

    Cape Town, 2004 - ( Steen van, E.), s. 2717-2723 ISBN 0-958-46636-X. [International Zeolite Conference /14./. Cape Town (ZA), 25.04.2004-30.04.2004] R&D Projects: GA ČR GA203/03/0804 Institutional research plan: CEZ:AV0Z4040901 Keywords : acylation of toluene * isobutyryl chloride * zeolites Subject RIV: CF - Physical ; Theoretical Chemistry

  9. Chloride migration in concrete with superabsorbent polymers

    OpenAIRE

    Hasholt, Marianne Tange; Jensen, Ole Mejlhede

    2015-01-01

    Superabsorbent polymers (SAP) can be used as a means for internal curing of concrete. In the present study, the development of transport properties of concrete with SAP is investigated. The chloride migration coefficient according to NT BUILD 492 is used as a measure of this. Twenty concrete mixtures aretested 7, 14, and 28 days after casting. The development of degree of hydration is followed for 20 corresponding paste mixtures.Both when SAP is added with extra water to compensate the SAP wa...

  10. Gasometric titration for dimethylaluminum chloride analysis.

    Science.gov (United States)

    Wang, Lin; Maligres, Peter; Eckenroad, Kyle; Simmons, Bryon

    2016-06-01

    A gasometric titration method was developed to quantitate active alkylaluminum content in dimethylaluminum chloride solution to perform the stoichiometry calculation for the reaction charge. The procedure was reproducible with good precision, and the results showed good correlation with ICP-MS method. The gasometric titration is a simple, inexpensive alternative to analysis via ICP-MS which provides more selective analysis of methylaluminum species without the need for inertion. PMID:27017569

  11. A Duplex Stainless Steel for Chloride Environments

    Science.gov (United States)

    Sridhar, N.; Kolts, J.; Flasche, L. H.

    1985-03-01

    This paper examines the effects of microstructural changes on the corrosion, stress corrosion cracking and corrosion fatigue resistance of a duplex stainless steel to chloride environments. The microstructural changes can be precipitation of phases such as sigma and carbides, or changes in the distribution of austenite and ferrite. The former can be important in hot forming operations while the latter is important in welding. The methods of minimizing these deleterious effects can sometimes be different from those used for austenitic stainless steel.

  12. Electrodeposition of Zinc from Chloride Solution

    OpenAIRE

    NAIK, Yanjerappa Arthoba; VENKATESHA, Thimmappa Venkatarangaiah

    2002-01-01

    The electroplating of zinc is carried out in the presence of 3,4,5-Trimethoxy benzaldehyde from a chloride bath. The bath constituents are optimized through Hull cell experiments. Operating parameters such as pH, temperature, and current density are also optimized. The current efficiency and throwing power are measured at different current densities. Polarization study is carried out under galvanostatic conditions. Corrosion resistance test indicated good protection of steel by the ...

  13. Manganese laser using manganese chloride as lasant

    Science.gov (United States)

    Chen, C. J.

    1974-01-01

    A manganese vapor laser utilizing manganese chloride as a lasant has been observed and investigated. Lasing is attained by means of two consecutive electrical discharges. The maximum laser output is obtained at a vapor pressure of about 3 torr, a temperature of 680 C, and a time delay between electrical discharges of 150 microsec. The maximum energy density is 1.3 microjoule per cu cm.

  14. Sodium and chloride levels in rainfall, mist, streamwater and groundwater at the Plynlimon catchments, mid-Wales: inferences on hydrological and chemical controls

    Directory of Open Access Journals (Sweden)

    C. Neal

    2000-01-01

    Full Text Available Variations in sodium and chloride in atmospheric inputs (rainfall and mist, stream runoff and groundwater stores are documented for the upper Severn River (Afon Hafren and Afon Hore catchments, Plynlimon, mid-Wales. The results show five salient features. Sodium and chloride concentrations are highly variable and highly correlated in rainfall and mist. The sodium-chloride relationship in rainfall has a slope close to the sodium/chloride ratio in sea-water, and an intercept that is not significantly different from zero. This indicates that sea-salt is the dominant source of both sodium and chloride in rainfall, which would be expected given the maritime nature of the metrology. For mist, there is also a straight line with near-zero intercept, but with a slightly higher gradient than the sea-salt ratio, presumably due to small additional sodium inputs from other sources. There is an approximate input-output balance for both sodium and chloride, with the exception of one groundwater well, in which high chemical weathering results in an anomalous high Na/Cl ratio. Thus, atmospheric deposition is the dominant source of both sodium and chloride in groundwater and streamflow. The fluctuations in sodium and chloride concentrations in the streams and groundwaters are strongly damped compared to those in the rain and the mist, reflecting the storage and mixing of waters in the subsurface. On all timescales, from weeks to years, sodium fluctuations are more strongly damped than chloride fluctuations in streamflow. The additional damping of sodium is consistent with ion exchange buffering of sodium in the catchment soils.  Sodium and chloride concentrations are linearly correlated in the streams and groundwaters, but the slope is almost universally less than the sea-salt ratio and there is a non-zero intercept. The Na/Cl ratio in streamflow and groundwater is higher than the sea-salt ratio when salinity is low and lower than the sea-salt ratio when

  15. Activity coefficients in (hydrogen chloride+holmium chloride) (aq) from T=(278.15 to 328.15) K

    International Nuclear Information System (INIS)

    Activity coefficients of HCl in (hydrogen chloride+holmium chloride) (aq) have been calculated from the observed e.m.f.s using the Nernst equation. The temperatures ranged from (278.15 to 328.15) K at 5 K intervals and at constant total ionic strengths of (0.01, 0.025, 0.05, 0.1, 0.25, 0.5, 1.0, and 1.5) mol.kg-1. Electromotive-force measurements were made on the cell without liquid junction of the type:Pt vertical bar H2(g,p=101.325kPa) vertical bar HCl(mA),HoCl3(mB) vertical bar AgCl(s), vertical bar Ag(s) The results of the activity coefficients of HCl for this mixed electrolyte mixture have been interpreted in terms of the simpler Harned's equations and the ion-interaction model of Pitzer. Results show that the quadratic term is sufficient for the full range of YB (the ionic strength fraction of the salt) to 0.9 at all the ionic strengths studied. The Pitzer's mixing parameters SθH,Ho and ΨH,Ho,Cl (including higher order electrostatic effects) and θH,Ho and ΨH,Ho,Cl (excluding higher order electrostatic effects) have been determined. These values at T=298.15 K are: SθH,Ho=0.115, ΨH,Ho,Cl=-.071; and θH,Ho=-.663, ΨH,Ho,Cl=0.165. The parameters obtained in this study reproduce the activity coefficients of HCl in the mixtures within 0.015 over the entire range of ionic strengths and within 0.009 for I>=0.05 mol.kg-1 over the entire temperature range

  16. Chloride Channel Myotonia: Study of Five Cases

    Directory of Open Access Journals (Sweden)

    M Ghofrani

    2002-09-01

    Full Text Available Chloride channel Myotonia is a form of channelopathy, and Myotonia is its manifestation. Myotonia may be defined as delayed relaxation of skeletal muscle after its contraction. Decreased chloride conductance across the transverse tubular system, renders the muscle membrane hyper-excitable and leads to repetitive firing, creating Myotonia. Myotonia congenital is another name for chloride channel Myotonia. Myotonia congenital appears in autosomal dominant type called Thomson disease, autosomal recessive type called Becker disease, and a type with sporadic occurrence. Symptoms appear in the first or second decade of life. Repeated muscle contraction, the so called warm up, result in resolution of the Myotonia stiffness. Muscle stiffness and hypertrophy is another finding at physical examination. In this study we report on 5 patients, which had clinical and electrical signs of Myotonia. Muscle hypertrophy and warm up phenomena were present in all cases. CPK measurement of all cases were normal. 2 patients underwent muscle biopsy that showed only atrophy and increased central nuclei. In three cases autosomal recessive inheritance (Becker, in one case autosomal dominant inheritance (Thomsen and in one case sporadic occurrence was suggested. With respect to successful results of carbamazepine therapy in 4 patients, and being excellent in one of them, we suggest carbamazepine for the first choice of Myotonia treatment.

  17. An autopsy case of zinc chloride poisoning.

    Science.gov (United States)

    Kondo, Takeshi; Takahashi, Motonori; Watanabe, Seiya; Ebina, Masatomo; Mizu, Daisuke; Ariyoshi, Koichi; Asano, Migiwa; Nagasaki, Yasushi; Ueno, Yasuhiro

    2016-07-01

    Ingestion of large amounts of zinc chloride causes corrosive gastroenteritis with vomiting, abdominal pain, and diarrhea. Some individuals experience shock after ingesting large amounts of zinc chloride, resulting in fatality. Here, we present the results of an administrative autopsy performed on a 70-year-old man who ingested zinc chloride solution and died. After drinking the solution, he developed vomiting, abdominal pain, and diarrhea, and called for an ambulance. Except for tachycardia, his vital signs were stable at presentation. However, he developed hypotension and severe metabolic acidosis and died. The patient's blood zinc concentration on arrival was high at 3030μg/dL. Liver cirrhosis with cloudy yellow ascites was observed, however, there were no clear findings of gastrointestinal perforation. The gastric mucosa was gray-brown, with sclerosis present in all gastric wall layers. Zinc staining was strongly positive in all layers. There was almost no postmortem degeneration of the gastric mucosal epithelium, and hypercontracture of the smooth muscle layer was observed. Measurement of the zinc concentration in the organs revealed the highest concentration in the gastric mucosa, followed by the pancreas and spleen. Clinically, corrosive gastroenteritis was the cause of death. However, although autopsy revealed solidification in the esophagus and gastric mucosa, there were no findings in the small or large intestine. Therefore, metabolic acidosis resulting from organ damage was the direct cause of death. PMID:27497327

  18. Potassium chloride production by microcline chlorination

    International Nuclear Information System (INIS)

    Highlights: • Use of chlorination for the KCl production. • The reagents used were microcline, hydromagnesite and chlorine. • Isothermal and non-isothermal assays were performed in Cl2–N2 mixture. • The chlorination generated KCl at 700 °C. • The chlorination products promote KCl formation. - Abstract: The potassium chloride is one of the most important fertilizers used in agriculture. The current demand of this salt makes interesting the study of potassium chloride production from unconventional potassium resources. In this work the potassium chloride production by chlorination of microcline was investigated. The starting reagents were microcline, hydromagnesite and chlorine. Non-isothermal and isothermal chlorination assays were carried out in a thermogravimetric device adapted to work in corrosive atmospheres. The temperature effect on potassium extraction and the phase transformations produced during chlorination of microcline were studied. The reagents and reaction products were analyzed by X-ray fluorescence (XRF) and X-ray diffraction (XRD). The experimental results indicated that by chlorination of microcline an important extraction of potassium in the temperature range from 800 to 900 °C was produced. Moreover, at 800 °C the forsterite, enstatite and magnesium aluminate spinel phases were generated

  19. Microwave spectrum and structure of nitrosyl chloride

    International Nuclear Information System (INIS)

    The microwave spectra of 15N isotopic species of nitrosyl chloride, 15NO35Cl and 15NO37Cl, have been assigned between 8 and 26 GHz, and the following rotational constants have been obtained: A = 81600 MHz, B = 5693.80 MHz, and C = 5322.44 MHz for 15NO35Cl, A = 81520 MHz, B = 5556.07 MHz, and C = 5201.56 MHz for 15NO37Cl. The microwave spectra of the normal species of nitrosyl chloride as well as the 37Cl species and the 18O species have already been measured by Millen et al. (1961). An analysis of both the rotational constants obtained in this study and the constants by Millen et al. has given the following bond lengths and angle as the complete r sub(s) structural parameters of nitrosyl chloride. r(N-O) = 1.143 +- 0.006 A, r(N-Cl) = 1.973 +- 0.003 A, and 0 +- 0.50. The nuclear quadrupole coupling constants in the N-Cl bond axis system of 15NO35Cl are X sub(zz) = -57.8 MHz and eta = -0.311. (author)

  20. Potassium chloride production by microcline chlorination

    Energy Technology Data Exchange (ETDEWEB)

    Orosco, Pablo, E-mail: porosco@unsl.edu.ar [Instituto de Investigaciones en Tecnología Química (INTEQUI), Chacabuco y Pedernera, San Luis (Argentina); Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Chacabuco y Pedernera, San Luis (Argentina); Ruiz, María del Carmen [Instituto de Investigaciones en Tecnología Química (INTEQUI), Chacabuco y Pedernera, San Luis (Argentina)

    2015-08-10

    Highlights: • Use of chlorination for the KCl production. • The reagents used were microcline, hydromagnesite and chlorine. • Isothermal and non-isothermal assays were performed in Cl{sub 2}–N{sub 2} mixture. • The chlorination generated KCl at 700 °C. • The chlorination products promote KCl formation. - Abstract: The potassium chloride is one of the most important fertilizers used in agriculture. The current demand of this salt makes interesting the study of potassium chloride production from unconventional potassium resources. In this work the potassium chloride production by chlorination of microcline was investigated. The starting reagents were microcline, hydromagnesite and chlorine. Non-isothermal and isothermal chlorination assays were carried out in a thermogravimetric device adapted to work in corrosive atmospheres. The temperature effect on potassium extraction and the phase transformations produced during chlorination of microcline were studied. The reagents and reaction products were analyzed by X-ray fluorescence (XRF) and X-ray diffraction (XRD). The experimental results indicated that by chlorination of microcline an important extraction of potassium in the temperature range from 800 to 900 °C was produced. Moreover, at 800 °C the forsterite, enstatite and magnesium aluminate spinel phases were generated.

  1. Liquid-Liquid Extraction and Separation of Co (II) and Ni(II) from Chloride Medium by bis (2,4,4-trimethylpentyl) dithio phosphinic acid in Kerosene

    International Nuclear Information System (INIS)

    The extraction of Co(II) and Ni(II) from chloride solutions using bis (2,4,4-trimethylpentyl) dithio phosphinic acid (CYANEX 301) in kerosene has been investigated. The various factors affecting the extraction process of Co(II) and Ni(II) by the investigated extractant such as contact time, ph, extractant and metal ion concentration as well as temperature, are separately investigated. The stripping of the extracted metal ions from loaded organic solutions is also carried out using different stripping reagents. The results were used to assess the conditions for maximum Co(II)/Ni(II) separation from chloride medium using CYANEX 301

  2. cis-Aqua­chloridobis(1,10-phenanthroline-κ2 N,N′)cobalt(II) chloride 2.5-hydrate

    OpenAIRE

    K. Arun Kumar; Dayalan, A.; Sethusankar, K.

    2009-01-01

    In the title complex, [CoCl(C12H8N2)2(H2O)]Cl·2.5H2O, the CoII ion is coordinated by four N atoms of two bis-chelating 1,10-phenanthroline (phen) ligands, one water molecule and a chloride ligand in a distorted octahedral environment. The dihedral angle between the two phen ligands is 84.21 (3)°. In the crystal structure, complex molecules and chloride ions are linked into centrosymmetric four-component clusters by intermolecular O—H...Cl hydrogen bonds. ...

  3. The Accelerated Test of Chloride Permeability of Concrete

    Institute of Scientific and Technical Information of China (English)

    TAN Ke-feng; ODD E Gjφrv

    2003-01-01

    The availability of accelerated chloride permeability test and the effect of w/c ratio, incorporation of silica fume, maximum aggregate size and aggregate type on the chloride permeability were studied. The mathematic analysis certifies that there is a linear relationship between accelerated test and natural diffusion. Test results show that the chloride permeability of concrete increases as w/c ratio increases whilst a limited amount of replacement of cement with silica fume, the chloride permeability decreases dramatically. The maximum aggregate size in the range of 8 to 25 mm seems also affect chloride permeability but with a much less significant level. The chloride permeability of silica fume lightweight aggregate concrete is very low, especially the concrete made with dry lightweight concrete. The chloride permeability can be evaluated by this accelerated test method.

  4. Influence of sulphate, chloride, and thiocyanate salts on formation of β-lactoglobulin-pectin microgels.

    Science.gov (United States)

    Hirt, Stacey; Jones, Owen G; Adijanto, Marilyn; Gilbert, Jay

    2014-12-01

    Effects of sulphate, chloride, and thiocyanate salts on the heat-induced formation of protein-based microgels from β-lactoglobulin-pectin complexes were determined as a function of pH and protein-to-polysaccharide ratio. Aggregation temperatures were initially decreased at low ionic strength due to shielding of electrostatic interactions between β-lactoglobulin and pectin but increased with further increases in ionic strength. Turbidity of heated mixtures and associated sizes of formed microgels were increased with up to 75 mmol kg(-1) ionic strength. Aggregation and microgel formation were relatively increased in the presence of thiocyanate salts compared to chloride salts and relatively decreased in the presence of sulphate salts, indicating that the inverse Hofmeister series was relevant in this system. Topographical analysis of dried microgels by atomic force microscopy verified that microgels were smallest in the presence of sulphate salts and showed that added ions, particularly thiocyanate, increased the deformability of microgels during drying. PMID:24996306

  5. Growth of L-Valinium Aluminium Chloride single crystal for OLED and super-capacitor applications

    Science.gov (United States)

    Kalaivani, D.; Vijayalakshmi, S.; Theras, J. Elberin Mary; Jayaraman, D.; Joseph, V.

    2015-12-01

    L-Valinium Aluminium Chloride (LVAC), a novel semi-organic material, was grown using slow evaporation under isothermal condition. The single crystal data reveal that the grown crystal belongs to monoclinic system. The SEM micrographs give clear picture about the surface morphology. Further, they confirm the inclusion of aluminium chloride into atomic sites of L-Valine. The compositional elements present in the crystal were identified through EDAX analysis. The mass spectral analysis was carried out to determine the molecular weight of the grown crystal. The optical transparency of the grown crystal was investigated by UV-vis-NIR spectrum. FTIR spectral study was used to identify the functional groups present in the grown material. The luminescence characteristics of grown material were analysed to confirm the effect of metal ion on the ligand. This property makes the material suitable for OLED application. The supercapacitive performance of the grown crystal was finally studied using cyclic voltammetry.

  6. Controlling the structure and rheology of TEMPO-oxidized cellulose in zinc chloride aqueous suspensions for fabricating advanced nanopaper

    Science.gov (United States)

    Wang, Sha; Zhang, Xin; Hu, Liangbing; Briber, Robert; Wang, Howard; Zhong, Linxin

    Due to its abundance, low-cost, biocompatibility and renewability, cellulose has become an attractive candidate as a functional material for various advanced applications. A key to novel applications is the control of the structure and rheology of suspensions of fibrous cellulose. Among many different approaches of preparing cellulose suspensions, zinc chloride addition to aqueous suspensions is regarded an effective practice. In this study, effects of ZnCl2 concentration on TEMPO-oxidized cellulose (TOC) nanofiber suspensions have been investigated. Highly-transparent cellulose nanofiber suspension can be rapidly obtained by dissolving TOC in 65 wt.% zinc chloride aqueous solutions at room temperature, whereas a transparent zinc ion cross-linked TOC gel could be obtained with zinc chloride concentration as low as 10 wt. %. The structural and rheological characteristics of TOC/ZnCl2 suspensions have been measured to correlate to the performance of thetransparent and flexible nanocellulose paper subsequently produced via vacuum filtration or wet-casting processes.

  7. Relation between chloride exchange diffusion and a conductive chloride pathway across the isolated skin of the toad (Bufo bufo)

    DEFF Research Database (Denmark)

    Kristensen, P; Larsen, Erik Hviid

    1978-01-01

    Substitution of chloride in the outside bathing medium of the toad skin with bromide, iodide, nitrate and sulphate leads to a reduction in the apparent exchange diffusion of chloride across this tissue, and also to a reduction of the chloride current recorded during hyperpolarization. A series of...... systems could be explained as secondary effects due to a primary interaction with the sodium transport mechanisms. A correlation was found between the clamping current recorded during hyperpolarization and the efflux of chloride under short circuit conditions with chloride Ringer's on both sides. On the...

  8. Iron(III) Chloride mediated reduction of Bis(1-isoquinolylcarbonyl)amide to an Amide

    Indian Academy of Sciences (India)

    Rojalin Sahu; Papuli Chaliha; Vadivelu Manivannan

    2016-01-01

    In methanol, FeCl3 reacted readily with L1H (L1H = bis(1-isoquinolylcarbonyl)amide) and afforded a complex having the formula [Fe(L2)Cl2] (1) {L2− = -((1-isoquinolyl)(methoxy)methyl)isoquinoline-1-carboxamide ion}. This reaction involves reduction of one of the two carbonyl groups present in L1H to (methoxy)methyl group. A plausible mechanism for the conversion of L1H to L2− has been proposed. Determination of molecular structure of 1 confirmed this conversion. Fe(III) ion is surrounded by three nitrogen atoms of the ligand and two chloride ions, imparting a rare distorted trigonal bipyramidal N3Cl2 coordination environment.

  9. Effect of calcium chloride addition on ice cream structure and quality.

    Science.gov (United States)

    Costa, F F; Resende, J V; Abreu, L R; Goff, H D

    2008-06-01

    The influence of calcium fortification by the addition of calcium chloride on quality parameters of ice cream based on physical properties was investigated, as was the effect of kappa-carrageenan at modifying the effects of this calcium fortification. Four ice cream mixes of conventional composition, with added kappa-carrageenan (0 or 0.025%) and added calcium chloride (0 or 4.4 g L(-1) = 40 mM of added Ca(2+)), were prepared. Modulated temperature-differential scanning calorimetry was used to investigate the effect of calcium chloride on the nucleation temperature, enthalpy of melting, and freezing point depression. The protein composition of 15.4% (wt/wt) reconstituted skim milk powder solutions with or without 4.4 g L(-1) added CaCl(2) and in the supernatant after ultracentrifugation was determined. Fat particle size distributions in ice cream were characterized by light scattering. Ice crystal sizes before and after temperature cycling were determined by cold-stage light microscopy. The results demonstrated that the addition of calcium chloride led to a substantial increase in ice crystal sizes and in fat partial coalescence, which were exacerbated by the addition of kappa-carrageenan. These results can be explained by the interaction between Ca(2+) ions and casein micelles, rather than any effects on freezing point depression. The calcium ions led to a more compact micelle, less serum beta-casein, and high fat destabilization, all of which would be expected to reduce macromolecular structure and volume occupancy in the unfrozen phase, which led to increased rates of ice recrystallization. PMID:18487638

  10. A chloride tolerant laccase from the plant pathogen ascomycete Botrytis aclada expressed at high levels in Pichia pastoris.

    Science.gov (United States)

    Kittl, Roman; Mueangtoom, Kitti; Gonaus, Christoph; Khazaneh, Shima Tahvilda; Sygmund, Christoph; Haltrich, Dietmar; Ludwig, Roland

    2012-01-20

    Fungal laccases from basidiomycetous fungi are thoroughly investigated in respect of catalytic mechanism and industrial applications, but the number of reported and well characterized ascomycetous laccases is much smaller although they exhibit interesting catalytic properties. We report on a highly chloride tolerant laccase produced by the plant pathogen ascomycete Botrytis aclada, which was recombinantly expressed in Pichia pastoris with an extremely high yield and purified to homogeneity. In a fed-batch fermentation, 495 mg L(-1) of laccase was measured in the medium, which is the highest concentration obtained for a laccase by a yeast expression system. The recombinant B. aclada laccase has a typical molecular mass of 61,565 Da for the amino acid chain. The pI is approximately 2.4, a very low value for a laccase. Glycosyl residues attached to the recombinant protein make up for approximately 27% of the total protein mass. B. aclada laccase exhibits very low K(M) values and high substrate turnover numbers for phenolic and non-phenolic substrates at acidic and near neutral pH. The enzyme's stability increases in the presence of chloride ions and, even more important, its substrate turnover is only weakly inhibited by chloride ions (I(50)=1.4M), which is in sharp contrast to most other described laccases. This high chloride tolerance is mandatory for some applications such as implantable biofuel cells and laccase catalyzed reactions, which suffer from the presence of chloride ions. The high expression yield permits fast and easy production for further basic and applied research. PMID:22178779

  11. Changes in ion transport in inflammatory disease

    Directory of Open Access Journals (Sweden)

    Eisenhut Michael

    2006-03-01

    Full Text Available Abstract Ion transport is essential for maintenance of transmembranous and transcellular electric potential, fluid transport and cellular volume. Disturbance of ion transport has been associated with cellular dysfunction, intra and extracellular edema and abnormalities of epithelial surface liquid volume. There is increasing evidence that conditions characterized by an intense local or systemic inflammatory response are associated with abnormal ion transport. This abnormal ion transport has been involved in the pathogenesis of conditions like hypovolemia due to fluid losses, hyponatremia and hypokalemia in diarrhoeal diseases, electrolyte abnormalites in pyelonephritis of early infancy, septicemia induced pulmonary edema, and in hypersecretion and edema induced by inflammatory reactions of the mucosa of the upper respiratory tract. Components of membranous ion transport systems, which have been shown to undergo a change in function during an inflammatory response include the sodium potassium ATPase, the epithelial sodium channel, the Cystic Fibrosis Transmembrane Conductance Regulator and calcium activated chloride channels and the sodium potassium chloride co-transporter. Inflammatory mediators, which influence ion transport are tumor necrosis factor, gamma interferon, interleukins, transforming growth factor, leukotrienes and bradykinin. They trigger the release of specific messengers like prostaglandins, nitric oxide and histamine which alter ion transport system function through specific receptors, intracellular second messengers and protein kinases. This review summarizes data on in vivo measurements of changes in ion transport in acute inflammatory conditions and in vitro studies, which have explored the underlying mechanisms. Potential interventions directed at a correction of the observed abnormalities are discussed.

  12. A mechanism for solvent extraction of first row transition metals from chloride media with the ionic liquid tetraoctylammonium oleate.

    Science.gov (United States)

    Parmentier, Dries; Vander Hoogerstraete, Tom; Banerjee, Dipanjan; Valia, Yash A; Metz, Sybrand J; Binnemans, Koen; Kroon, Maaike C

    2016-06-21

    Aqueous waste streams of the metallurgical industry often contain considerable concentrations of metal salts. Previous research showed that the metal chloride salts of zinc(ii), manganese(ii) and iron(iii) can be recovered by solvent extraction using a sustainable and renewable fatty acid based ionic liquid as the extractant. In this paper, the extraction mechanism of Zn(ii), Co(ii) and Ni(ii) from chloride media has been studied systematically. The metal extraction performances of the precursors, sodium oleate and tetraoctylammonium chloride, were compared to the extraction performance of the ionic liquid tetraoctylammonium oleate. Slope analysis experiments were performed to determine the number of ionic liquid molecules involved in the extraction. The experimental data showed that Co(ii) and Ni(ii) were extracted in the pH range from 6 to 8 by the formation of negatively charged metal carboxylate complexes with tetraalkylammonium counter ions. In contrast, Zn(ii) gets extracted as a mixed metal chloride carboxylate anionic complex with tetraalkylammonium counter ions. This extraction mechanism was supported by EXAFS measurements. PMID:27220984

  13. Molecular mechanisms of carcinogenesis by vinyl chloride.

    Science.gov (United States)

    Dogliotti, Eugenia

    2006-01-01

    In 1974 vinyl chloride (VC), a gas used in the plastics industry, was shown to be a human carcinogen, inducing a very rare type of tumor, angiosarcoma of the liver. The same type of tumor was induced in rodents exposed to VC thus providing an excellent model for mechanistic studies. Here, we review the numerous studies on the mechanism of action of VC with particular emphasis on the DNA products induced by this strong alkylating agent. In particular, the genotoxicity, repair mechanisms, in vivo formation and tumor mutation spectra by etheno-adducts will be analysed and possible approaches for future research suggested. PMID:17033136

  14. Solidification of supercooled molten zinc chloride

    Czech Academy of Sciences Publication Activity Database

    Rodová, Miroslava; Cihlář, Antonín; Nitsch, Karel

    Bratislava: x, 2005 - (Koman, M.; Mikloš, D.), s. 5-9 ISBN 80-89088-42-2. [Development of Materials Science in Research and Education - DMS -RE 2005 /15./. Kežmarské Žĺaby (SK), 05.09.2005-09.09.2005] R&D Projects: GA ČR(CZ) GA202/03/0428 Institutional research plan: CEZ:AV0Z10100521 Keywords : molten zinc chloride * thermal analysis * crystallization * glass formation Subject RIV: BM - Solid Matter Physics ; Magnetism

  15. Benzalkonium Chloride Intoxication Mimicking Herpes Zoster Encephalitis

    Directory of Open Access Journals (Sweden)

    Ekrem Güler

    2011-06-01

    Full Text Available Benzalkonium chloride (BAC is a frequently used disinfectant and its most well-known side effect is contact dermatitis. In this report, two children who had vesicular dermatitis, headache, lethargy, fever and encephalopathy mimicking Herpes zoster encephalitis were presented. Their consciousness level improved on the second day. From the medical history it was understood that the mother had applied 20% BAC solution to the scalps of two children. The aim of the presentation of this report is to draw attention to the fact that BAC application to the scalp for treating pediculosis capitis may resemble the herpes encephalitis clinical picture.

  16. Raman spectroscopic studies of chemical speciation in calcium chloride melts

    Energy Technology Data Exchange (ETDEWEB)

    Windisch, Charles F.; Lavender, Curt A.

    2005-02-01

    Raman spectroscopy was applied to CaCl2 melts at 900 degrees C under both non-electrolyzed and electrolyzed conditions. The later used titania cathodes supplied by TIMET, Inc. and graphite anodes. Use of pulse-gating to collect the Raman spectra successfully eliminated any interference from black-body radiation and other stray light. The spectrum of molten CaCl2 exhibited no distinct, resolvable bands that could be correlated with a calcium chloride complex similar to MgCl42- in MgCl2 melts. Rather, the low frequency region of the spectrum was dominated by a broad “tail” arising from collective oscillations of both charge and mass in the molten salt “network.” Additions of both CaO and Ca at concentrations of a percent or two resulted in no new features in the spectra. Addition of CO2, both chemically and via electrolysis at concentrations dictated by stability and solubility at 900 degrees C and 1 bar pressure, also produced no new bands that could be correlated with either dissolved CO2 or the carbonate ion. These results indicated that Raman spectroscopy, at least under the conditions evaluated in the research, was not well suited for following the reactions and coordination chemistry of calcium ions, nor species such as dissolved metallic Ca and CO2 that are suspected to impact current efficiency in titanium electrolysis cells using molten CaCl2. Raman spectra of TIMET titania electrodes were successfully obtained as a function of temperature up to 900 degrees C, both in air and in-situ in CaCl2 melts. However, spectra of these electrodes could only be obtained when the material was in the unreduced state. When reduced, either with hydrogen or within an electrolysis cell, the resulting electrodes exhibited no measurable Raman bands under the conditions used in this work.

  17. Extraction of scandium by benzoylantipyrine from chloride-perchlorate solutions

    International Nuclear Information System (INIS)

    Distribution of scandium complexes in case of extraction by benzoyl-4-antipyrine (BANT) in chloroform from aqueous chloride-perchlorate solutions, depending on extraction, perchlorate-ion and salting out agents concentration, was studied. It has been ascertained that scandium distribution factor is nearly 50 at NaClO4 and BANT concentrations equal to 2 and 0.1 mol/l respectively. Introduction of salting out agents (NaCl, CaCl2) and HCl at a constant content of NaClO4 (0.5 mol/l) increases noticeably scandium extraction. For 0.1 mol/l BANT solution in chloroform the extraction capacity in terms of scandium makes up 1.26 g/l. The optimal conditions for the element extraction have been found, the composition of the complex extracted has been ascertained (Sc:BANT:ClO4- = 1:3:3) and extraction mechanism has been suggested. Influence of interfering elements on scandium distribution factor was studied

  18. Passivity of Alloy 22 in Chloride and Fluoride Containing Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Carranza, R M; Rodr?guez, M A; Rebak, R B

    2005-06-07

    The aim of the present work was to study the passive behavior of Alloy 22 in chloride and fluoride containing solutions varying the heat treatment of the alloy, the halide concentration and the pH of the solution at 90 C. General corrosion behavior was studied using electrochemical techniques, which included open circuit potential monitoring over time, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements carried out at open circuit and at passive potentials. Corrosion rates obtained by EIS measurements after 24 h immersion were below 0.5 {micro}m/year. The corrosion rates were practically independent of the solution pH, short term corrosion potential (E{sub corr}), alloy heat treatment and halide ion nature and concentration. Polarization resistance (R{sub P}) values increased with open circuit potential and the polarization time at constant potential in 1M NaCl, pH 6, 90 C. This was attributed to an increase in the oxide film thickness and oxide film aging. Capacitance measurements indicated that passive oxide on Alloy 22 presented a double n-type/p-type semiconductor behavior in the passive potential range.

  19. Corrosion of alloy 22 in phosphate and chloride containing solutions

    International Nuclear Information System (INIS)

    Alloy C-22 is a Ni-based alloy (22% Cr, 13% Mo, 3% W y 3% Fe in weight per cent) that exhibits an excellent uniform and localized corrosion resistance due to its protective passive film. It was designed to resist the most aggressive environments for industrial applications. Alloy 22 is one of the candidates to be considered for the outer shell of the canister that would contain high level radioactive nuclear wastes. The effect of phosphate ion in chloride containing solutions at 90 C degrees was studied under aggressive conditions were this material might be susceptible to crevice corrosion. The electrolyte solution, which consisted of 1M NaCl and different phosphate concentrations (between 10-3M and 1M), was deoxygenated by bubbling with nitrogen. Electrochemical tests, electron microscope observations (SEM) and energy dispersive spectrometer analysis (EDS) were conducted. Crevice corrosion was not detected and the comparison of the potentiodynamic polarization tests showed an increase of the passivity range in phosphate containing solutions. The passive current value was 1 μA/cm2 approximately in all the tests that were performed in this work. The differences in composition of the anodic film formed on the samples suggest that phosphate is responsible for the increase of the passivity range by incorporation to the passive film. (author)

  20. Chloride regulates afferent arteriolar contraction in response to depolarization

    DEFF Research Database (Denmark)

    Hansen, P B; Jensen, B L; Skott, O

    1998-01-01

    afferent arterioles. In 70% of vessels examined, K+-induced contraction was abolished by acute substitution of bath chloride. Consecutive addition of Cl- (30, 60, 80, 100, 110, and 117 mmol/L) restored the sensitivity to K+, and half-maximal response was observed at 82 mmol/L chloride. The calcium channel...... results show that K+-induced contraction of smooth muscle cells in the afferent arteriole is highly sensitive to chloride, whereas neurotransmitter release and ensuing contraction is not dependent on chloride. Thus, there are different activation pathways for depolarizing vasoconstrictors and for the......-Renal vascular reactivity is influenced by the level of dietary salt intake. Recent in vitro data suggest that afferent arteriolar contractility is modulated by extracellular chloride. In the present study, we assessed the influence of chloride on K+-induced contraction in isolated perfused rabbit...