Search results

Summary Chlorinated rubber primers formulated with active pigments, which are claimed to be non‐toxic and non‐polluting, are investigated; they are designed for the protection of ships (above the waterline), port installation, industrial plants, bridges, etc.

The problems involved in the choice of priming paint for galvanized steel are discussed in this article and explained on a chemical basis. Case histories are given of the successful use of metallic lead primer together with photographs which show the result of cross hatch tests on a variety of primers.

1. Zinc Zinc was closely linked with copper as a sacrificial partner and because of this relationship an increased use was found for the metal in the 19th century. Around 1838 particular interest was being shown by scientists in the protective power of zinc when in contact with other metals and articles indicate that a scientific appreciation of the principles involved was evident.

During the second day of the symposium on ‘The Protection of Structural Steel’ interest again centred on the comparative advantages of paint and metal coatings. Speakers discussed the composition of good paint protective systems and the application of sprayed metal coatings, and some consideration was given to the relative cost of the two methods. A report of the papers read during the first day was given in the May issue of CORROSION TECHNOLOGY.

Korea and China have promoted a bilateral FTA since 2005 to upgrade their economic relationships. If the Korea-China FTA is concluded, then trade between the two countries is likely to involve substantial changes both quantitatively and qualitatively. Offer lists submitted by Korea include steel, petrochemicals and machinery and those by China include some agricultural and marine products as well as nonferrous metals. Korea's interest in the Korea-China FTA has focused mainly on damage to the agricultural sector and there have been a lot of studies on the effects of the FTA on Korean agricultural sector. However, little is known about why China includes the nonferrous metals industry for early voluntary liberalization and its implications for the domestic economy. Nonferrous metals industry is one of China’s national strategic sectors and has a large supply excess in the country. This study targets the survey of Chinese nonferrous metals industry and trade structure and considers the problem of nonferrous metals in the context of negotiations for the Korea-China FTA and its implications for a higher-quality Korea-China FTA.

THE EXTENSIVE use of steel can be attributed to its many physical and mechanical properties and low cost when compared to other materials. It has, however, one major disadvantage in that it will corrode in many environments.

This paper aims to develop an inexpensive, portable, sensitive and environmentally friendly electrochemical sensor to quantify trace metals.

A sensor was constructed by modifying carbon paste electrode for the determination of lead, cadmium and zinc ions using square wave anodic stripping voltammetry (SWASV). The modified electrode was prepared by inserting homogeneous mixture of 2-hydroxy-acetophenonethiosemicarbazone, graphite powder and mineral oil. Various important parameters controlling the performance of the sensor were investigated and optimized. Electrochemical behavior of modified electrode was characterized by cyclic voltammetry.

Modified carbon pastes electrodes showed three distinct peaks at −0.50, −0.76 and −1.02 V vs silver/silver chloride corresponding to the oxidation of lead, cadmium and zinc ions at the electrode surface, respectively. The highest peak currents for all the metal ions under study were observed in the phosphate buffer solution at pH 1 with a deposition time of 70 s. The sensor exhibited linear behavior in the range of 0.25-12.5 μg mL-1 for lead and cadmium and 0.25-10.0 μg mL⁻¹ for zinc. The limit of detection was calculated as 78.81, 96.17 and 91.88 ng mL⁻¹ for Pb2⁺, Cd2⁺and Zn2⁺, respectively. The modified electrode exhibited good stability and repeatability.

A chemically modified electrode with Schiff base was applied to determine the content of cadmium, lead and zinc ions in aqueous solutions using SWASV.

A report that zinc chromate, like lead chromate, may be a health hazard brings to mind the considerable researches on zinc and lead chromes which have gone on since the Scottish chemist James Murdock discovered zinc chrome in 1807. Such bright pigments, together with anti‐corrosion processes such as the Cronak chromate passivation, brought considerable demands for chromium, with chemical derivatives of the element as varied as applications in metallurgy.