Concentrations Of Ionic Components Research Articles

Electrodialysis Desalination with Simultaneous pH Adjustment Using Bilayer and Bipolar Membranes, Modeling and Experiment.

A kinetic model of the bipolar electrodialysis process with a two-chamber unit cell formed by a bilayer (bipolar or asymmetric bipolar) and cation-exchange membrane is proposed. The model allows describing various processes: pH adjustment of strong electrolyte solutions, the conversion of a salt of a weak acid, pH adjustment of a mixture of strong and weak electrolytes. The model considers the non-ideal selectivity of the bilayer membrane, as well as the competitive transfer of cations (hydrogen and sodium ions) through the cation-exchange membrane. Analytical expressions are obtained that describe the kinetic dependences of pH and concentration of ionic components in the desalination (acidification) compartment for various cases. Comparison of experimental data with calculations results show a good qualitative and, in some cases, quantitative agreement between experimental and calculated data. The model can be used to predict the performance of small bipolar membrane electrodialysis modules designed for pH adjustment processes.

The Ionic Component of PM2.5 May Be Associated with Respiratory Symptoms and Peak Expiratory Flow Rate

(1) Background: Few studies have evaluated the association between the ionic components of PM2.5 and respiratory symptoms or peak expiratory flow rate (PEFR). The aim of this study was to clarify these associations. (2) Methods: Patients with allergic diseases treated at Fukuoka Hospital recorded their morning and evening PEFR and respiratory symptoms in a diary. We measured PM2.5 and its ionic components in Fukuoka City and examined the relationship with PEFR and respiratory symptoms by univariate and multivariate analysis. (3) Results: Among the ionic components of PM2.5, Cl−, NO3−, Na+, K+, and Mg2+ were significantly correlated with the frequency of coughing and nasal symptoms. In univariate analysis, the concentrations of each of the above ions was significantly associated with a decrease in PEFR and the concentrations of each was associated with at least one respiratory symptom or PEFR. Multivariate analysis of items significantly correlated with PEFR indicated that the concentration of ionic components may predict changes in PEFR. (4) Conclusions: In patients with allergic diseases, some ionic components of PM2.5 may increase the frequency of respiratory symptoms and decrease PEFR, so further study and caution are required in daily clinical practice.

Correlation between electronic micro-roughness and surface topography in two-dimensional surface conducting hydrogen-terminated diamond

The influence of surface topography on phase coherent transport in the two-dimensional (2D) hole band of surface transfer doped hydrogen-terminated (100) diamond is investigated. Low-temperature magneto-conductance measurements were carried out with an applied in-plane magnetic field to quantify the effect of electronic micro-roughness on spin dephasing in the 2D hole band for Hall bar devices with similar transport characteristics, but significantly different topographic roughness. The electronic micro-roughness of the 2D hole band, described by the parameter d2L, where d is the root-mean-square (rms) fluctuation in the width of the quantum well and L is the correlation length of the fluctuations, is found to increase for surfaces with increased roughness. Fluctuations in the well width likely arise from a locally varying hole carrier density, arising for example from a local variation in the concentration of ionic components in the surface water layer.

Concentration of Ionic Components in Rain Water at Mt. Ohdaigahara, a Mountainous Area

Concentration of Ionic Components in Rain Water at Mt. Ohdaigahara, a Mountainous Area

The Chemical Characteristics of Springtime Precipitation in Lushan Mountains, East China

Abstract A comprehensive field measurement was set up in the springtime of 1993 to study the chemical characteristics of precipitation in the Lushan Mountains. The results showed that the concentrations of gaseous SO2, NOx, NH3, and HNO3 were low and precipitation was seriously acidified. The pH of all samples was less than 5.6 with an average of 4.6 and a minimum of 3.71. Sulfuric acid was the primary acidic substance to cause the acidification and nitric acid was the secondary. Both acidity and concentrations of compositions in cloud water were much higher than those in rainwater. Comparisons of different phases of precipitation showed that concentrations of ionic components in the solid phase were two to five times higher than those in rainwater, and its pH was 0.6 higher than that of rainwater. According to the measurement results, it was postulated that the acidification of precipitation was caused by joint effects of washout of local atmospheric pollutants and long-distance transportation of acidic ...

Accessibility and multivalency of immobilized Cibacron blue F3GA.

The effect of immobilized dye concentration on protein complexation was observed using zonal chromatography. A monomeric protein, octopine dehydrogenase, was retained by a single interaction to a Sepharose CL-6B column containing 11.6 mM immobilized Cibacron blue F3GA. By contrast, a tetrameric protein, lactate dehydrogenase, was retained by the same column by multiple interactions. The degree of multiple interactions was found to systematically increase with increasing immobilized dye concentration. The concentration of immobilized dye accessible to protein was found to be inversely related to the concentration of ionic components in the solvent. Zonal chromatographic measurements of free dye and unconjugated matrix suggest that increasing the concentration of ionic components promotes the adsorption of immobilized dye to the adjacent matrix surface. Such adsorption markedly affects both the capacity of an immobilized dye column and the multiplicity of its interaction with oligomeric proteins.