Search results

The purpose of this paper is to study to minimize the self‐corrosion rate of Type 57S aluminium containing (97.7 per cent Al, 2 per cent Mn and 0.03 per cent Mg) in 2 M NaOH solution containing 0.2 M zinc oxide and 700 ppm of polyaniline.

The approach is used to measure weight loss and polarization measurements.

Results obtained show that as the amount of polyaniline is increased, the self‐corrosion rate of Alloy 57S aluminium decreases appreciably. Additionally, the open circuit potential is more in the case of 700 ppm level of polyaniline (−1.630 V) compare to 600 ppm level of polyaniline (−1.587 V). From this paper, it is also observed that the anodic polarization is greater than the cathodic polarization, thereby indicating that the overall corrosion of Alloy 57S 2 M NaOH containing 0.2 M ZnO and 700 ppm of polyaniline is under anodic control.

The results of the study clearly reveal that the overall corrosion of Alloy 57S aluminium in 2 M NaOH containing 0.2 M ZnO and 700 ppm of polyaniline is under anodic control. Hence, the 57S grade aluminium can be used as a potential candidate (anode) in alkaline batteries.

The purpose of this paper is to show how to develop inhibition 57S aluminium in 2M NaOH solution.

The approach is used to measure gravimetric and polarization measurements.

The results of the paper clearly reveal that the 0.2 M ZnO with 700 ppm polyaniline in N‐methyl‐2‐pyrrolidone solution is found to offer inhibition up to 71.2 per cent.

The paper deals with the development of newer inhibitor based on polyaniline. Gravimetric and galvanostatic methods were employed to evaluate inhibition efficiency.

The performance of commercial aluminium as a sacrificial anode for cathodic protection of mild steel in 0.3% sodium chloride has been studied in alkaline compositions for anolyte based on slaked lime. The influence of several addition agents has been investigated with a view to suppressing local cell action in the above‐mentioned environment.

The purpose of this paper is to investigate the inhibiting properties of six quaternary ammonium salts, three cationic surfactants and two non‐ionic surfactants in 2 M KOH. An attempt also was made to correlate some molecular parameters of these compounds with their corrosion inhibitor efficiency.

The inhibition efficiencies of quaternary ammonium salts, cationic surfactants and non‐ionic surfactants on the corrosion of zinc in 2 M KOH solution were investigated by potentiodynamic polarisation, electrochemical impedance spectroscopy and linear polarisation methods.

Inhibition efficiencies of quaternary ammonium salts were found to be due to physical absorption on the cathodic sides of zinc electrode and dependence of inhibition efficiencies on substituents were found. Physical adsorption of cationic surfactants on zinc electrode slowed down both anodic and cathodic reactions; thus they were found to be mixed type inhibitors. On the other hand, inhibition behaviour of non‐ionic surfactants was found to be due to adsorption on zinc via polar groups. It was found that non‐ionic surfactants behaved as mixed type inhibitors.

Clarifies the role of molecular structure and substituents on the inhibition efficiency of surfactants and quaternary ammonium compounds on the corrosion of zinc in alkaline media.

The corrosion of steel in sulphuric acid containing hexadecyl trimethyl ammonium bromide (HTABr) was studied over the temperature range 30‐60°C at different inhibitor concentrations of 0.5 × 10^‐3 to 2.5 × 10^‐3 M/L by the mass‐loss method. Langmuir’s adsorption isotherm fits the experimental data for the studied compound. Thermodynamic parameters for dissolution and adsorption were calculated. It is observed that HTABr can be used as an effective inhibitor.

Inhibition of carboxylic acids of aluminium corrosion in hydrochloric acid and sodium hydroxide solutions has been studied using weight‐loss and hydrogen evolution methods. The order of inhibition action of aromatic acids depends on the number and position of the carboxylic groups and the other substituents in the benzene ring. Increase of the chain length increases the inhibiting power of aliphatic acids. The inhibition efficiency in NaOH is higher than that in HCI solutions. The action of inhibition was discussed in terms of the chemical structure of the inhibitors.

GERMANY Preparing metal surfaces with liquid jets A comparative newcomer among the many conventional methods of surface treatment and finishing is the technique of using liquid jets. A method designed to permit multi‐purpose surface treatment in a single series of operations has been developed in Switzerland and is described in Technisclie Zeitschrift für praktische Metalbearbeitung (No. 5, 1964) by O. Burnand, Lausanne.

The influence of thiophenol on the corrosion and hydrogen permeation 1M HCl and 0.SM H₂SO₄ has weightloss measurements, gasometric studies and other electrochemical techniques. Thiophenol inhibits the corrosion of mild steel in both the acids, but it is found to be more effective in H₂SO₄. It behaves predominantly as a cathodic inhibitor. It brings down the permeation current in both the acids, but is more effective in H₂SO₄. The adsorption of thiophenol on the mild steel surface from both the acids obeys Temkin’s adsorption isotherm.

This study assesses changing aesthetic values and their characteristics in urban environments based on human perception. With this in mind, a model for assessing the aesthetic values of the urban environment based on the three steps of human cognition has been developed to elaborate the user's perception in different urban environments.

The results of the survey confirm that by changing urban morphology the aesthetic perception of the environment also changes. The finding of this research opens up a new window for urban planners to assess the aesthetic effects of the elements of urban spatial configuration for future urban development.

Conflicts are a form of man-made disaster changing the economy of nations, influencing energy concerns, food, shelter and demographic distributions. The breakdown of global systems has become a huge concern that needs working mechanisms to develop resilient cities. The working mechanisms vary from one country to another, thus making the process a complex reality. Resilience is a word that was derived from the Latin word “resalire” which means “to spring back”. In this work, the housing environment was considered as a system constituting of several subsystems (Social, Environmental, Political, Economic subsystems). It argues that for resilience to occur within the post-conflict housing environment there is a need for an inclusive evaluation of users' preferences and expectations. With a focus on the social subsystem, it tried to determine the level of significance of gender, age, income and level of exposure on the perceived social character of a post-conflict housing environment and the satisfaction derived thereof. The study showed the importance of inclusivity as it influences perception and satisfaction. Using regression analysis, the study revealed that Perception and satisfaction within a post-conflict housing environment were influenced by age (73%), gender (74%), income and level of exposure (54%).