Effect of pressure on the conductivities of HCl and KCl in water at 0°C

The electrical conductivities of hydrochloric acid and potassium chloride in water have been measured in the concentration range of 3×10 ^–4 –10 ^–3 moles-dm ^–3 at 0°C up to 3500 bar. The limiting molar conductance (₀) for HCl increases with increasing pressure, while ₀(KCl) has a maximum around 1700 bar. The excess conductance of hydrogen ion [ ₀ ^E =₀(HCl)–₀(KCl)] increases with increasing pressure. Its pressure dependence indicates that the reorientation of water molecules, which is the rate-determining step in the proton jump, becomes faster at higher pressure. This anomaly is attributed to the distortion with pressure of the hydrogen bonds in water.     

Thermodynamics of mixed electrolyte solutions. VIII. An isopiestic study of the ternary system KCl−MgCl2−H2O at 25°C

The osmotic coefficients of aqueous solutions of mixtures of potassium and magnesium chlorides were derived from isopiestic measurements at 25°C. The isopiestic data were treated by the methods of both Scatchard and Friedman, and the results obtained agree very well over the ionic strength range of 1–5. Interaction coefficients were obtained from both formalisms. Excess free energies of mixing were calculated and compared with those of similar systems.     

Activity coefficients of KCl in PEG 4000 + water mixtures at 288.15, 298.15 and 308.15 K

The electromotive force of the cell containing two ion-selective electrodes (ISE), K-ISE|KCl(m), PEG 4000(Y), H₂O(100 − Y)|Cl-ISE has been measured at temperatures of 288.15, 298.15, and 308.15 K as a function of the weight percentage Y of PEG 4000 in a mixed solvent. Y was varied between 0 and 25 wt.% in five-unit steps and the molality of the electrolyte (m) was between ca. 0.05 mol kg⁻¹ and almost saturation. The values of the standard electromotive force were calculated using routine methods of extrapolation together with extended Debye-Hückel and Pitzer equations. The results obtained produced good internal consistency for all the temperatures studied. Once the standard electromotive force was determined, mean ionic activity coefficients for KCl, Gibbs energy of transfer from the water to PEG 4000 + water mixtures, interaction parameters (g_EN, h_EN, s_EN, c_p,EN), salting constants, and the KCl primary hydration number were estimated and comparatively discussed in terms of a model of structural and electrostatic interactions with those of the LiCl and NaCl previously obtained in similar mixtures.     

盐对粘土／氢氧化铝镁／甘油胶体性能的影响

通过电泳淌度、流变参数和中压滤失量的测定，研究了ＫＣｌ和ＡｌＣｌ３对带永久负电荷的蒙脱土与带永久正电荷的氢氧化铝镁／甘油形成的混合悬浮体胶体性能的影响，并对影响机理进行了深入探讨     

Analysis of polar compounds on PEG-40M/KF glass capillary columns

The chromatographic properties of potassium fluoride as an additive to the polyethylene glycol stationary phase were investigated. This unique base in organic chemistry was shown to succeed in yielding good results for the analysis of polar compounds, including the primary amines. Glass capillary columns of high selectivity for primary and secondary aliphatic amines were obtained by the “hexane plug” procedure by which a thin layer of KF is deposited on the inner surface of glass capillary columns. Some possible types of donor-acceptor interactions occuring within the system PEG/KF/solute were considered.     

Study on solid–liquid phase equilibria in ionic liquid: 1. The solubility of alkali chloride (MCl) in ionic liquid EMISE

This paper reports the solubility of alkali chloride MCl (M is Li, Na and K) in IL EMISE was measured in the temperature range of 293.15 K to 343.15 K. The relationship between solubility, m and temperature T may be expressed in an empiric formula: ln(m/m⁰) = A₁ + A₂T₀/T + A₃T/T⁰, where m⁰ is 1 mol/kg, T⁰ is 1 K. The observed sequence of solubility is LiCl > NaCl > KCl. The fact implies that the less the radius of alkali ion, the greater is its solubility because little ion is easy to get into the interstices of IL EMISE.     

The limiting partial molar volume and apparent molar volume of glycylglycine in aqueous KCl solution at 298.15 and 308.15 K

Apparent molar volumes V_Φ of glycylglycine in aqueous KCl solutions have been obtained from densities at 298.15 and 308.15 K measured with a vibrating-tube densimeter. These data have been used to deduce partial molar volumes of transfer from water to different KCl–water mixtures. values are positive. This result arises from the interaction of KCl with the charged centers of glycylglycine. The results show that depends less on temperature. Hydration numbers are calculated from data and are interpreted in terms of various interactions.     

Thermodynamics of mixed electrolyte solutions. IX. Calculation of the osmotic and activity coefficients in a pseudoternary system (NaCl−nKCl)−MgCl2-H2O at 298.15°K

The equation of Reilly, Wood, and Robinson was used to predict the osmotic coefficient of a pseudoternary system (NaCl–nKCl)–MgCl₂–H₂O over a molal ionic strength range of 1.0 to 5.0 moles-kg^–1. The results are in close agreement with experimental data at most ionic strengths. The standard deviation in the osmotic coefficients over the entire concentration range lies within 0.0035. The predicted values of the mean activity coefficients are in good agreement with those obtained by the treatments of both Scatchard and Friedman. Mean activity coefficients for the other components were also predicted.     

对SERS衬底表面杂质的处理研究

化学沉积法制备的SERS衬底表面有时会引入杂质分子,所以在进行分子的SERS研究时,时有杂质的拉曼峰干扰。实验尝试利用KCl溶液浸泡除去银镜表面杂质的方法,取得了预期的效果。并把处理后的银镜用于分子的检测研究。这种方法简单易行,为分子的SERS研究提供了一条便利途径。     

Rapid growth of KDP crystal from aqueous solutions with additives and its optical studies

Potassium Chloride (KCl) and Ethylene diamine tetraacetie acid (EDTA) as new additives were added into the KDP solutions in a small amount (5M% and 0.01M% respectively). The solubility curve and metastable zone width of KDP solution with 5M%KCl was determined and we explained the mechanism of rapid growth of KDP crystal with KCl additve. The clear transparent crystal of KDP with a dimension of 54 × 54 × 42 mm have been grown rapidly by cooling solution method in 2 days. The crystal grown from additives added solution was subjected to optical transmission and laser damage threshold studies as compared with the crystal grown by traditional growing method. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)