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The efficacy of octylamine as a vapour phase corrosion inhibitor in different corrosive environments for carbon steel, copper and brass, and its biocidal action, have been examined. The protection of these metals from atmospheric corrosion using VPI (octylamine)‐impregnated paper was monitored by visual observation, weight loss measurements, polarisation scans and impedance measurements. The long‐term protection given by octylamine‐impregnated paper to these metals was examined by Stevenson’s chamber test. It was found that octylamine offered more than 80 per cent protection against atmospheric corrosion for carbon steel, copper and brass.

Introduction Amines have been known for a number of years as effective corrosion inhibitors. Their efficiency is attributed to the presence of the nitrogen atom acting as the active centre for the adsorption of organic molecules on the metal surface. Several aliphatic and aromatic amines have been reported to serve as effective corrosion inhibitors for iron and steel in acidic solutions. The nitrogen‐containing corrosion inhibitor exhibited a very good performance in hydrochloric acid, but very little effect in sulphuric acid. Hence a study of the mechanism by which the corrosion rate is reduced when these organic compounds are added to solutions is of interest. In this study the inhibition of corrosion of mild steel in HCl and H2SO4 has been studied using different electrochemical techniques. Results are reported and discussed.

This paper aims to study the effect of ultraviolet (UV) light on the corrosion behavior of BC550 weathering steel in simulated marine atmospheric environment.

The effect of UV light on the corrosion behavior of BC550 weathering steel in simulated marine atmospheric environments were investigated by the corrosion weight gain experiment, in situ electrochemical noise, scanning electron microscope and X-ray diffraction.

UV light accelerated the corrosion process of BC550 weathering steel in the simulated marine atmospheric environment during the first 168 h. The maximum influence factor of UV light was 0.32, and it was only 0.08 after 168 h of corrosion process.

As the extension of corrosion time, the thickness and density of the corrosion product layer increased, which weakened the acceleration effect of UV light.

The purpose of this paper is to draw up an atmospheric corrosion map for an industrial zone to determine the best coating system for each location.

The outdoor atmospheric corrosion rate was measured at eight locations distributed in an oil refinery during a year. Corrosion rates were measured by weight loss of carbon steel coupons, according to ISO Standard 9223. Weathering conditions, including temperature, time of wetness, and atmospheric pollution such as chloride precipitation and sulfur content also were measured. The results were analyzed using “Surfer 8” software and the corrosion map of the refinery was derived.

An atmospheric corrosion map was derived for the oil refinery. By this approach, coating system for equipment can be selected based exactly on where the plant item is located.

Exterior coating systems for equipment now can be selected based on their application, regardless of their position in any refinery. In this article, an atmospheric corrosion map was developed for a refinery for the first time. The position of equipment on the corrosion map is a new parameter that should be considered for coating system selection.

This paper aims to investigate the corrosion behaviour of carbon steel in the Mauritian atmosphere over a three-year period. Atmospheric corrosion is a serious problem in Mauritius.

Carbon steel samples were exposed outdoors at various sites. Mass loss analysis was performed to determine the corrosion behaviour of the metal over the exposure period. Scanning electron microscopy and Raman tests were performed to investigate the formation of the corrosion products on the carbon steel surface.

It was found that the corrosion loss at two of the sites considered did not vary clearly according to the bilogarithmic law. Time of wetness was found to be a main factor affecting atmospheric corrosion in Mauritius. The corrosivity of the atmosphere was found to lie between categories C3 and C4, according to ISO 9223.

The results can be of essential help to the construction industry, especially as steel buildings are becoming very common in Mauritius. Moreover, as Mauritius is a tropical island, the results obtained can be useful in other tropical islands.

The purpose of this paper is to obtain a better insight into the impact of atmospheric corrosion in Mauritius by investigating the corrosion prevention strategies used in the country and determining the related costs.

Companies and organizations, in various industrial sectors, affected by atmospheric corrosion were selected. They were inspected and surveys were performed in order to fulfill the aim of the study.

It has been observed that extensive atmospheric corrosion problems have been encountered in the capital city, leading to the use of a range of corrosion prevention methods. However, carbon steel, which corrodes easily, is very commonly used in the country. This leads to the wide use of alkyd‐based barrier coatings. The cost of atmospheric corrosion has been found to be equal to 0.38 per cent of the GDP.

This study is expected to raise concern on the problem of atmospheric corrosion in Mauritius and the related waste in materials.

This study is expected to help in adopting corrosion prevention policies and strategies in Mauritius.

The purpose of this paper is exploratory. The author seeks to put forward propositions on how firms may best conceive business risks in an environment characterised by constant change and uncertainty. To construct such a reality, the author examines how the military manages its engagement with strategic risk and uncertainty.

The paper presents a summated examination of literature published over the last four decades covering three major areas of management literature; risk management, competitive strategy and military tactics are conducted.

The propositions which are put forward provide the foundation for the empirical development of an appropriate framework for strategic risk management.

The major contribution of the study is that it has focused readers on not only strategic risk and competition, but on how lessons can be drawn from the military's experience of dealing with irregular forms of competition.

The purpose of this paper is to examine the key contemporary paradigms of management and leadership based upon an evolving linguistic analysis that is rich in the development of these concepts. Following this examination, the justification of the perspective of managerial leadership is put forth as a legitimate combination of these two concepts for usage in the modern global context.

From a European perspective, the paradigms of management and leadership are based upon a rich linguistic heritage that bridges the boundaries of several basic languages. These linguistic bases are examined; and following that, an extensive analysis of the relationship between the functions of management and leadership is presented, and a unique justification of the contemporary perspective of managerial leadership is developed.

In essence, the changes that have typically occurred regarding the paradigms of management and leadership have evolved from linguistic bases that have treated the two conceptual frameworks to be quite similar, and in some contexts virtually interchangeable, to paradigms of understanding that now treat them as being quite distinctive in scope and meaning. This treatise presents an exploration into the conceptual changes that have occurred in the linguistic cross‐cultural meanings of management and leadership, and shows that the distinction between the responsibilities of these two organizational roles, although not universally recognized, does exist in reality.

The basic value of this analysis rests with the examination of the distinct contemporary paradigms of management and leadership, and the case made for managerial leadership as a necessary ingredient for organizational success.

This paper aims to investigate the corrosion behavior of zinc in a typical hot and dry atmosphere. It proposes the dynamic corrosion for different exposure periods. Results can provide the basic data and corrosion mechanism of zinc in such environment.

In this paper, the authors investigated the corrosion behavior of pure zinc exposed in the typical hot and dry environment in Turpan for one-four years, which has never been studied. Scanning electron microscopy, laser scanning confocal microscopy, electron probe micro-analyzer (EPMA), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) were conducted to measure the corrosion morphology and products of zinc. Finally, combining electrochemical impedance spectroscopy and scanning Kelvin probe techniques, the corrosion mechanism of zinc in Turpan was examined.

The thickness loss of the zinc followed an exponential law with respect to exposure time: D = 3.17 t^0.61, and both of the rust layer resistance and the charge transfer resistance increased with exposure time. The corrosion products mainly comprised ZnO, Zn(OH)₂, Zn₅(CO₃)₂(OH)₆, Zn₄SO₄(OH)₆·5H₂O and Zn₁₂(SO₄)₃Cl₃(OH)₁₅·5H₂O. The Kelvin potentials shifted toward the positive direction from −0.380 to −0.262 V (vs saturated calomel electrode [SCE]) when the exposure time extended from one to four years and the distribution of the corrosion products became more and more uniform.

The corrosion behavior of pure zinc in the typical hot and dry environment in Turpan has not been studied. The dynamic corrosion for different exposure periods was obtained. The corrosion products were systemically investigated via energy-dispersive X-ray spectroscopy, EPMA, XPS and XRD.

Low nickel austenitic stainless steel (ASS) has attracted much attention worldwide because of its economical price. This study aims to investigate the effect of different corrosive environments on the corrosion behavior of chrome-manganese (Cr-Mn) ASS. The tests were carried out as a function of H₂SO₄ concentrations, temperature and addition of ammonium thiocyanate (NH₄SCN) (0.01 M). Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques were used to study the corrosion behavior of Cr-Mn ASS. It was observed that with increasing H₂SO₄ concentration, temperature and with the addition of NH₄SCN solution, icorr, icrit and ipassive values increased. EIS data show decreasing charge transfer resistance value with increasing concentration and temperature. Higher corrosion rate with increasing temperature and concentration of H₂SO₄ is related to the anions (SO₄²⁻), which is responsible for reducing the stability of passive films. With the presence of 0.01 M NH₄SCN thiocyanate (SCN⁻ anion), there is a higher dilution of the passive film resulting in a higher corrosion rate. Energy-dispersive spectroscopy (EDS) analysis reveals the adsorption of sulfur on the surface in NH₄SCN containing a solution. The significant presence of counter ions and the adsorbed sulfur species on the steel surface play a vital role in corrosion behavior.

All the experiments were performed on a 3 mm thick sheet of Cr-Mn ASS (202 ASS) in hot rolled condition. The samples were then annealed at 1,050°C for 1 h, followed by water quenching. For microstructural examination, they were electrochemically etched in 10 Wt.% oxalic acid solution at 1 amp for 90 s. A computer-controlled Potentiostat (Biologic VMP-300) was used. After the cell was set up, the working electrode (WE) was electrostatically cleaned at −1 V vs saturated calomel electrode (SCE) for 30 s to remove the air-formed film. Then, WE were allowed to attain stable open circuit potential (OCP) for 1 h, following by the EIS test and potentiodynamic polarization test. The polarization test was started from a cathodic potential (−1.2 V vs SCE) and continued up to an anodic potential (1.6 V vs SCE) a scan rate of 0.1667 mV/s. EIS experiment was conducted on the same instrument by using a sinusoidal AC signal of 10 mV in a frequency range of 1,000,000 to 0.01 Hz at OCP.

Potentiodynamic polarization graph shows that with the increase in sulphuric acid concentration. Increasing temperature from 20°C to 80°C in 0.5 M H₂SO₄ solution increases the corrosion rate (icorr) of Cr-Mn ASS. On the addition of 0.01 M NH₄SCN to the sulfuric acid solution (0.1, 0.5 and 1 M) the corrosion rate increases drastically almost four to five times. EDS and XRD analysis shows the presence of sulfur over the oxide film and preferential site for dissolution of Cr and Mn at the steel surface when NH₄SCN is added to the sulfuric acid solution.

A study on the corrosion behavior of Cr-Mn ASS is scanty according to the author’s knowledge. Therefore, the present study will investigate the corrosion behavior of Cr-Mn ASS on SO₄⁻² anions, temperature and the addition of SCN⁻ ion in sulfuric acid.