Kind Of Electrolyte Research Articles

INFLUENCE OF VARIOUS ELECTROLYTES ON DIFFUSION OF ORANGE II THROUGH LIQUIDS IN THE PORE OF CELLOPHANES AND IN THE BULK

The generally accepted model for diffusion of ionic dyes into cellulosic substrate is based on a heterogeneous system in which dye anions diffuse through the liquid in the pore of the substrate and are simultaneously adsorbed on the pore walls. By use of this model investigations were carried out to study the diffusion of Orange II through cellophanes containing carboxyl groups in the presence of various electrolytes (NaCl, Na2SO4, CH3COONa, C2H5COONa, C6H5COONa, CH3C (CH3) CH2SO3Na and C6H5SO3Na) at 50°C.A linear relationship was found between the square root of the obtained diffusion coefficient through the liquid in the pore and the reciprocal of the square root of the ionic strength of each electrolyte. These results could be explained by means of the equation by Warwicker and other investigators.However, the diffusion coefficients didn't depend only on the ionic strength, but also on the kind of electrolyte; i.e. the electrolytes having SO-3 group increased the diffusion coefficient more markedly than those having COO- group. The same effect was observed also in the diffusion coefficient in the bulk liquid, which was measured by the capillary method.Such variation of diffusion coefficient with the kind of electrolyte was explained by the generally accepted suggestion that water structure around SO3- group is broken and that around COO- group is enhanced.

Electrodeposited mixed hexaborides of sodium and lanthanum

The electrolytic preparation of the mixed hexaborides of sodium and lanthanum, Na x La 1− x B 6, has been carried out and some physical constants of the borides have been measured. In order to obtain three kinds of borides: x = 0, x with a value close to the upper limit, and x with a value between zero and the upper limit, three kinds of electrolyte were formulated. The constituents were: (1) lanthanum oxide, calcium tetraborate and calcium chloride; (2) lanthanum oxide, sodium tetraborate and sodium chloride; (3) the same ingredients as for electrolyte (2) but with a lower lanthanum oxide content. The chemical formulae of the electrodeposited borides determined from chemical analyses were: melt (1) La 0.96B 6; melt (2) Na 0.23La 0.60B 6; and melt (3) Na 0.43La 0.56B 6. From the experimental results it was observed that, as the sodium content in the boride increases, the specific gravity of the boride decreases and the lattice constant increases slightly. A smaller amount of CaB 6 codeposited with LaB 6 was obtained from melt (1) in which calcium metaborate and anhydrous boric acid were substituted for calcium tetraborate.

Anodic Extraction of Vanadium from VC-type Carbide Produced by Carbothermic Reduction

The anodic dissolution of vanadium from VC-type carbide was investigated in two kinds of electrolytes, KCl–NaCl–NaF–K2NaVF6(44–44–7–5 mol%) and KF–NaF–K2NaVF6(62–33–5 mol%), in the temperature range of 700–850°C and in the cell voltage range of 0.8–1.4 V. A high degree of vanadium extraction was made from the spongy vanadium monocarbide anode which was prepared carbothermically from a mixture of V2O5 and medium coal tar pitch. This anode did not disintegrate even at an extraction percentage of 98%. Anode current efficiency of 40–50% and a high degree of vanadium extraction were obtained under the electrolytic conditions of 1.0–1.2 V and 825°C in the KF–NaF–K2NaVF6 electrolyte and also 1.4 V and 725°C in the KCl–NaCl–NaF–K2NaVF6 electrolyte.

Surface conductance of silica in electrolyte solutions

Three kinds of silica samples were prepared by treating Aerosil at different temperatures, being used for the measurements of electrokinetic potential by means of streaming potential method and for those of surface conductance in solutions of various kinds of electrolytes. The results obtained indicate that both the surface conductance and surface charge density are strongly affected in a similar way by the type of electrolyte used, being larger in a solution containing higher valent ions than in a solution containing lower valent ions. Furthermore, the experimental values of surface conductance were exceedingly higher than the calculated ones by applying Bikerman's theory. These facts give evidence that the surface conductance is caused by ion transfer not only in the diffuse double layer but also in the fixed double layer. It was also found that the surface roughness is responsible for the values of electrokinetic potential, but has no effect on the surface conductance.

Cyclic Voltammetry of Platinum in Weakly-acidic Aqueous Solutions

電解質としてNa露SO4,NaNO3,KNO3あるいはKClを含む弱酸性水溶液中における白金の電解挙動をサイクリックボルタンメトリーによって調べた。これらの溶液で得られたボルタングラムは強酸性,中性およびアルカリ性溶液の場合に通常観測されるものとは非常に異なっていた。とくに弱酸性溶液中で白金電極を電位走査すると,-α5Vvs.SCE付近に-対の可逆な酸化還元電流が観測された。拡散律速の水素イオン放電反応に帰属されるこの可逆波の出現は走査電位領域,走査速度,電解質の種類,pH値などに依存することがわかった。また,これらの系での電極反応を評価するための,適当な電極の前処理法についても弱干の考察を行なった。

電解加工における各種加工液の加工特性について

In this report the machining characteristics of some electrolytes for carbon steel (S 15 C) and austenitic stainless steel (SUS 27) were experimentally investigated. The electrolytes were sodium chloride solution including sodium sulfite, sodium chloride solution including sodium hexametaphosphite and calcium chloride, sodium nitrite solution, potassium bromide solution, and sodium chlorate solution, which are less corrosive for mild steel than sodium chloride solution. The main results are as follows.(1) In the case of sodium chlorate solution the two materials can not be machined by single-phase half-wave current, but by square wave current. The surface finishes by the latter are slightly worse than those in sodium chloride solution, but the machined forms are rather sharper. The surface roughness is not affected by the pH value of the solution in the range from 6 to 11.(2) In the case of other electrolytes better surface roughnesses are obtained by square wave current than by single-phase half-wave rectified current. The surface roughness of carbon steel is not affected by the kind of electrolyte, and the surface roughnesses are within a range from 4 to 6 μ Hmax. The surface roughnesses of austenitic stainless steel are within a range from 1 to 2 μ Hmax in other electrolytes besides potassium bromide solution.

Concentration Dependence of Permeability Coefficients to an Electrolyte Component across Bovine Lens Capsule In Vitro

Theoretical and experimental studies have been made on permeability coefficients to various kinds of electrolyte across lens capsules that are dissected from bovine eyes and that are found to be positively fixed charged membranes from our experiments of membrane potentials. The differential permeability coefficient, P(m), is defined as J(s) = P(m)(C(2) - C(1)), where J(s) is the flux of an electrolyte component in moles per sec across unit area of the lens capsule that separates two aqueous solutions of the same electrolyte at different concentrations, C(2) and C(1). Various types of strong electrolytes were studied; KCl, NaCl, Cacl(2), MgSO(4), MgCl(2) and LaCl(3). It was found that at C(2)/C(1) = constant, P(m) decreases to zero as C(2) decreases and P(m) increases to a limiting value, (P(m))(infinity), that is characteristic for the system of the salt used and the membrane as C(2) increases, despite of electrolytes. We assumed in theory that single ion activity coefficients of co-ion and gegen-ion are ideal, that the systems studied are in electric neutrality, that the fixed charge density of the membrane is independent of concentrations C(2), and that Donnan equilibrium holds between the bulk solution and membrane surface. Although the concentration-dependent changes of P(m) were quantitatively different depending on the type of electrolyte used, general agreement between theory and experiment was obtained over a wide range of concentrations except for the case of very dilute solutions.

Rapid measurements of diffusion coefficients of electrolytes in aqueous solutions by the diaphragm-cell method

A cell for the rapid measurement of diffusion coefficients of electrolytes in aqueous solutions has been made by using a sheet of Millipore filter as a diaphragm, and the diffusion coefficients of several kinds of electrolytes have been measured in aqueous solutions. The diffusion coefficients obtained were in good agreement with the values determined by a conventional sintered-glass diaphragm cell and with values reported in literature.

VARIATIONS OF THE ELECTRIC CONDUCTIVITY OF THE SKIN IN RELATION TO SWEATING

Detailed relations between the electric conductivity of the skin and sweating were investigated by simultaneous, continuous recordings of skin conductivity and sweat rate on a pen-writing oscillograph in healthy sub jects and patients with anhidrosis. Evidence is presented that skin conductivity is mainly a function of sweating. The specific electric conductivity of the paste or solution used for the skin electrodes affected largely the patterns of fluctuations of skin conductivity, whereas the kind of electrolyte in the solution had little influence on it. Characteristic changes of conductivity of the palmar skin were noted. The movement of the electrolyte ions into sweat-ducts appears to be the most important factor affecting variations of skin conductivity with sweating. Possible changes in size of sweat-ducts in association with the activity of sweat glands are assumed also to participate in these mechanisms. Various patterns of variations of skin conductivity are discussed on the basis of these assumptions.

HYDROPHILIC AND HYDROPHOBIC COLLOIDS AND THE INFLUENCE OF ELECTROLYTES ON MEMBRANE POTENTIALS AND CATAPHORETIC POTENTIALS

1. In order to be able to compare the effects of electrolytes on membrane potentials and cataphoretic potentials it seems necessary to distinguish between the charging and depressing effect of electrolytes on these potentials. Only low concentrations of acids and alkalies have a charging effect on the membrane potentials of proteins, while low concentrations of neutral salts have only a depressing effect; in the case of the cataphoretic potentials, low concentrations of salts have a charging effect as have also low concentrations of alkalies and in some cases low concentrations of acids. This difference finds its explanation in the difference of the origin of the two potentials and there can therefore be no common theory for the charging effect of electrolytes in the two cases. 2. There exists, however, an analogy in the depressing action of electrolytes on the two types of potentials inasmuch when the maximal P.D. is reached, all three kinds of electrolytes, acids, alkalies, and neutral salts, have a depressing effect on both types of potentials (taking into due consideration the effect of changes in the hydrogen ion concentration). 3. This depressing effect is adequately explained for the membrane potentials of protein solutions and protein gels on the basis of the Donnan equilibrium, and the question arises whether the same explanation may also hold for the cataphoretic potentials. 4. The active ion in the depressing action of electrolytes on membrane potentials as well as on cataphoretic potentials has the opposite sign of charge from that of the colloidal particle. It had been shown before that only the valency but not the chemical nature of the active ion determines the depressing effect in the case of membrane potentials and it is shown in this paper that the same is true for the cataphoretic potentials of particles of collodion, mastic, Acheson's graphite, and denatured egg albumin. 5. It is shown that the same valency rule holds also for the effect of acids on the cataphoretic potentials of collodion particles coated with gelatin, and that the ratio of the effect of dibasic to that of mono-basic acids is approximately 0.66, as Donnan's theory of membrane potentials would demand. 6. If we have a right to conclude from the validity of the valency rule for cataphoretic potentials that the depressing effect of electrolytes on the cataphoretic P.D. is determined by the Donnan equilibrium, we can understand the analogy between the depressing action of electrolytes on membrane potentials of hydrophilic colloids and on the cataphoretic potentials of hydrophobic colloids. We can also understand the analogy between the influence of electrolytes on the precipitation of hydrophobic colloids and on the depression of the values of all those properties of hydrophilic colloids which depend on the Donnan equilibrium, since the precipitation of hydrophobic colloids occurs when the cataphoretic P.D. is depressed below a critical value.