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The purpose of this study, 3-aminopyridine, 8-aminoquinoline and some new synthesized 2-aminobenzothiazoles were diazotized with nitrosyl sulfuric acid and subsequently coupled with 5-chloro-8-hydroxy quinoline to synthesize the corresponding heteroarylazo dyes 6–13.

The structures of dyes were characterized by mass, Fourier transform infra red, ¹H proton nuclear magnetic resonance and ultra violet-visible spectroscopic techniques. Absorption spectra of the dyes were measured in acetic acid, ethanol, chloroform, acetonitrile, dimethyl formamide and dimethyl sulfoxide and correlated with the nature of the solvents and substituents. The effects of varying pH on the absorption wavelengths of the azo dyes were also studied. In addition, the acidity constants (pKa) of the dyes were determined using the spectrophotometric method in an ethanol-water mixture (80:20, v/v) at 20–23°C. Besides, density functional theory (DFT) calculations were carried out to compare the energies of proposed azo and hydrazone tautomers of the dyes.

The results showed that the withdrawing chloro groups on the diazo moiety have significant influence (red shift) on the electron absorption spectra of these dyes. In addition, introducing electron withdrawing chloro groups into the benzothiazoles moiety increased the acidic character of dyes.

The synthesized 7-hetroarylazo-5-chloro-8-hydroxy quinoline dyes are new members in the 8-hydroxyquinoline azo dyes family, where very few details regarding the synthesis of such dyes are reported before in the literature. They are unique in terms of synthesis, spectral properties and DFT calculations.

The purpose of this paper is to study the release of corrosion inhibitor from nanocontainers and to show that it can be released due to reaction with the substrate induced by corrosion. This is called self‐healing of corrosion. Raman spectroscopy was used to show that reaction after scratching of the surface and corrosion of the substrate.

TiO₂ nanocontainers loaded with 8‐hydroxyquinoline (8‐HQ) were placed onto a copper substrate and wetted with in 0.05 M NaCl solution. The Raman spectrum of the modified copper surface was attributed to the Cu(8‐Q)2 compound. The incorporation of loaded nanocontainers into epoxy coatings showed enhanced protection against corrosion. Artificial defects were formed on the coatings in order to evaluate the corrosion process and the possible self‐healing effect. The Raman spectra in the scratch tentatively assigned to Cu(8‐Q)2 compound. This result shows that the enhanced anti‐corrosive properties of the films with loaded nanocontainers can be attributed to the released inhibitor from the nanocontainer.

The authors found that the corrosion of copper substrate induces the release of hydroxyquinoline and formation of a chelate. This is the self‐healing phenomenon.

This can be employed for self‐healing in all structures, such as mechanical properties of bridges, etc.

Damage occurs in all structures: the cost is immense – millions of dollars. Damage also occurs after an earthquake, accidents, etc. Self‐repairing is the key issue in modern science, therefore this article is of great importance.

The originality is that the authors showed, with Raman spectroscopy, that the chemicals in the nanocontainers in the coatings are released by the corrosion induced in the metal. This is the first spectroscopic proof of self‐healing.

The discovery of the Hall‐Herqult process for the manufacture of aluminium made it possible to obtain the metal in large quantities. Soon it attained the position of a major industrial metal due to its lightness combined with strength, capacity to take up a high polish, excellent conductivity of heat and electricity. Moreover it gives a wide range of extremely valuable alloys with diverse elements such as copper, magnesium, nickel, silicon, zinc, etc.

This paper aims to focus on the synthesis of the macrocyclic complexes (Cu and Zn) and their applications as anticorrosive materials in epoxy paint formulation for surface coating application.

A selected macrocyclic Cu(II) and Zn(II) complexes were prepared via template synthesis and characterized using Fourier transform infrared, thermal gravimetric analysis, scanning electron microscope, flexibility, hardness and adhesion of coating films prepared using epoxy paint.

The corrosion resistance of the epoxy-painted films was improved due to the incorporation of the Zn and Cu complexes into the formulation.

It was found that the metal complex-based formulation with Cu(II) and Zn(II) had outperformed the sample blank.

This paper aims to provide details of miniaturised analytical instrument technologies and developments.

Following an introduction and historical background, this first considers miniaturised chromatographs and spectrometers based on micro-electromechanical system (MEMS)/micro total analytical system technologies. It then discusses lab-on-a-chip developments with an emphasis on capillary electrophoresis. Developments in the emerging lab-on-paper technology are then considered and are followed by brief concluding comments.

This shows that many classes of analytical instruments which offer a number of operational and economic benefits have been miniaturised through the use of microfabrication and other technologies. They are an active field of research and are based on silicon, glass, polymers and even paper and are underpinned by developments in microfluidics and optofluidics and fabrication techniques which include lithography, MEMS and micro-opto-electromechanical system.

This provides an insight into the rapidly developing field of miniaturised analytical instrument technologies.

The coatings industry eagerly observes scientific developments which can be basic to the improvement of coating products. An interesting item in Chemical Industry Update (September 8, (1983) p.7) indicates that at the University of Connecticut Health Centre a peptide adhesive has been synthesised which duplicates the natural glue found in shellfish. It comprises ten repeating amino acids and is related to the material which barnacles exude and which causes them to cling so tenaciously to boat hulls. It is proposed that this adhesive be used for mending fractured bones and attaching torn tendons. Also it could have application in the dental field. Although practical application of such a material in coatings is far removed from the present, it is not unreasonable to believe that such a peptide properly formulated could provide either an adhesive coating or a coating additive.

This paper aims to enhance the barrier properties and active protection of a water-based silane coating on mild steel through nanoclay and zinc acetylacetonate simultaneously included into the formulation.

The corrosion protection performance of the silane sol-gel coatings with no additive, zinc acetylacetonate, nanoclay and nanoclay + zinc acetylacetonate was monitored using electrochemical impedance spectroscopy during 5 h of immersion in a sodium chloride solution. Moreover, the surface of coatings was analyzed using a field emission scanning electron microscopy equipped with an energy dispersive X-ray spectrometer (FESEM-EDX) and water contact angle measurements.

In electrochemical impedance spectroscopy analysis, the impedance at low frequencies, coating resistance and charge transfer resistance were the parameters considered which indicated the superiority of silane coating formulated with both nanoclay and zinc acetylacetonate. According to the results of FESEM/EDX and water contact angle measurements, the superiority was linked with the enhancement in the barrier properties in the presence of nanoclay, as well as function of the corrosion inhibitor at coating–substrate interface.

According to the literature, there is no research conducted to study the impact of the simultaneous use of nanoclay and zinc acetylacetonate on the barrier properties and active protection of an eco-friendly silane sol-gel coating including glycidyloxypropyltrimethoxysilane, tetraethoxysilane and methyltriethoxysilane on mild steel in a sodium chloride solution.

A new area for the maintenance coatings specialist is found in nuclear installations where coatings are necessary which are not contaminated by radioactive materials or which are readily cleaned if there is suspicion of contamination. The testing of coatings for nuclear containment has been discussed in an article by Burger (Metal Finishing, May, 1982, p. 127). Such coatings, the author points out, must be able to withstand exposure to high humidities and, at the same time, exposure to radiation dosage. In addition, the coatings must be sufficiently durable to withstand the conditions which would be anticipated during an accident. To meet these challenges provides a new opportunity for coatings chemists. A bibliography related to testing of nuclear coatings is listed by the author, and from these he concludes that the most significant are the Design Basis Accident or DBA test. This is a test to tell whether the coating will stand up if, in fact, there is an accident. The second test relates to irradiation, and the third to decontamination factors. These are described in detail by the author. He points out that a coating that passes these tests will meet the 40‐year expected life within a nuclear power containment facility.

In the recently published Annual Report for 1983 of the International Tin Research Institute, there is an extensive report on the Institute's studies on organotin chemistry. The sections of particular interest to paint manufacturers are published below.

This paper aims to investigate the inhibition effect of sodium silicate (SS), sodium alginate (SA) and sodium tungstate (ST) on the corrosion behavior of AZ91D magnesium alloy in 3.5 per cent NaCl solution through polarization curve test at room temperature, electrochemical impedance spectroscopy and weight loss measurement.

The influence of SA concentration on the inhibition efficiency of the corrosion inhibitor was mainly analyzed. The corrosion morphology and inhibition mechanism of the samples were also analyzed with scanning electron microscopy and energy-dispersive spectroscopy.

The results show that with the increase of SA concentration, the corrosion inhibition first increases and then decreases. When SA concentration is 0.03 mol/L, the inhibition efficiency is the highest, reaching 98 per cent. The adsorption film formed by SA and other deposition films produce a synergistic effect on the improvement of corrosion resistance of AZ91D magnesium alloy.

The adsorption film formed by SA with other deposition films produces a synergistic effect on the improvement of corrosion resistance of AZ91D magnesium alloy. With the increase of SA concentration, the corrosion inhibition first increases and then decreases. When the concentrations of SA, SS and ST are 0.03 mol/L, 0.015 mol/L and 0.02 mol/L, respectively, the inhibition efficiency of the inhibitor is the highest, reaching 98 per cent.