Conductivity as a New Monitoring Technique for Zinc Metal Corrosion and Corrosion Processes

The electrical conductivity method was successfully applied to monitor the corrosion and corrosion inhibition processes of zinc metal. Measurements of electrical conductivity at 20.0 oC of three different corrosive solutions (NaCl, HCl and NaOH) were performed with two different concentrations (0.10 and 1.00 M) containing zinc sheets in the absence and presence of four different concentrations of sodium lignosulfonate (1.0, 5.0, 10.0, and 20.0 mM). The analysis of curves that illustrates the changes in electrical conductivity of these solutions provides qualitative information about the strength of corrosion as well as the extent of corrosion inhibition behavior. The results obtained from electrical conductivity measurements revealed that sodium lignosulfonate was an effective corrosion inhibitor in acidic medium (for both 0.10 and 1.00 M HCl) in which it converted into lignosulfonic acid, but was less effective in salt and alkaline media.

The Kinetics of Magnesium Carbonate Crystallization for Traditional Salt Production Wastewater Recovery

The kinetics of crystallization of magnesium carbonate (nesquehonite) at room temperature (27°C) has been examined using an electrical conductivity method during process of nucleation. Magnesium carbonate hydrate from a reaction of magnesium chloride (MgCl2) and sodium carbonate (Na2CO3) in supersaturated condition was analyzed. Variations of batch reactor experimental are magnesium chloride initial concentration (500-3.000 mg/L) and operating pH (8-14). In this paper, we studied the crystallization kinetics of magnesium carbonate via an electrical conductivity method, a concentration monitoring method. By monitoring electrical conductivity during the solution reaction process, changes in [Mg2+] can be measured and an induction period of nucleation could be determined. Crystal has been formed was confirmed with powder X-ray Diffractometer (XRD) analyses. The results show that magnesium carbonate is formed during operating condition pH 10 with magnesium chloride initial concentration 3.000 mg/L. The nucleation process of magnesium carbonate crystallization can be represented by second-order reaction equation with R2 is 0.8. The induction period of magnesium carbonate crystallization is 50 second.

Development of a New Method for the Highly Effective Identification of Cold Resistance in Living Avocado Varieties

This paper first identified the cold resistance of 38 varieties of avocado by determining the semi-lethal low temperature (LT50) of the leaves using an electrical conductivity method in combination with a logistic function, and then analyzed the correlation between the LT50 of 27 varieties and the capacitance measured 9 different parts of the leaves in vivo, to explore the relationship between the cold resistance of various avocado varieties and the capacitance of different parts of avocado leaves, so as to develop a new method for highly effective identification of cold resistance of living avocado varieties. The results showed that various avocado varieties’ LT50 was significantly positively correlated with the capacitance of some parts of leaves, showing that the cold resistance of various avocado varieties was negatively correlated with the capacitance of various leaf parts. The results of mango variety trials conducted for comparison is coincident with the theoretical conclusion reached in the identification of the cold resistance of the avocado. So as to the study of the cold resistance of avocado and mango varieties, the capacitance of live mature leaves measured in the field can be used as a new method for the judgment of cold resistance.HighlightA new method for identification of avocado cold resistance through measuring the capacitance of different parts of leaves was developed. This method are simple, quick and efficient.