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Reports on the determination of rates of electropolishing of copper by measuring the limiting current of anodic dissolution of copper in phosphoric acid and in (water‐acetone) ‐phosphoric acid mixtures. Notes that the rate of electropolishing is decreased in (water‐acetone) ‐phosphoric acid mixtures and that the percentage inhibition of dissolution depends on the mole fraction of acetone, and its dielectric constant. Concludes with calculation of the thermodynamic parameters of activation.

An investigation of the behaviour of a soluble resin coating on a steel substrate was carried out by open circuit potential and electrochemical techniques. Exposure conditions were with artificial sea‐water and natural sea‐water. The anticorrosion properties of the soluble resin material and its protection of the steel panel from marine corrosion were estimated by comparison with the untreated steel. The weight effect of the film coating and the temperature of the media were also studied.

The objective of the present work was to study the kinetics of copper cementation on Fe metal in an acetone‐water medium and in a dioxane‐water medium.

The impact of solvent concentration on cementation rate was determined by measuring the rate of copper cementation from CuSO₄ onto an iron plate in the absence and in the presence of acetone and dioxane solvents.The thermodynamic parameters ΔH^#, ΔS^# and ΔG^# of the cementation of CuSO₄‐organic solvents were calculated. Linear plots of ΔH^# versus ΔS^# were obtained.

It was demonstrated that the rate of cementation decreased with increasing concentration of solvents and increasing temperature. The isokinetic temperature data indicate that the cementation reaction is controlled by the entropy of the system.

The findings have important implications for the reclamation of toxic and valuable metals from industrial waste streams.

The object of the present work is to study the kinetics of removal of Pb⁺⁺ on zinc rods in the presence and absence of three surface active substances (SAS) at different concentrations of SAS and different temperatures.

The paper uses a range of recently published (1973‐2003) works, which aim to provide practical and theoretical information about lead, which is a very toxic metal.

Lead tends to accumulate a sediment, from which it can be released by various processes of remobilization and in many cases it enters the food chain and is concentrated in fish and other edible organisms. The reaction can be considered as taking place via six steps.

The work is a list of recent papers which have been published in different European journals and magazines.

The determination of change of Pb⁺⁺ concentrations was carried out using a Perkin‐Elmer atomic absorption Spectrophotometer.

The rate of PbII/Zn cementation reaction in the presence of surfactants as non‐ionic (Triton‐X‐100), anionic (SDS) and cationic (CTAB) decreased compared with the blank solution (lead nitrate solution). The order of decreasing rate was as follows: Triton‐X‐100 > CTAB > SDS. The rate of cementation was increased by temperature and the value of ΔE* ranged between 27 and 33 kJmol⁻¹, which indicated that the reaction is a diffusion‐controlled process. The presence of two different SAS in the solution is more effective than the presence of one only.

Three thiosemicarbazone derivatives were synthesised: p‐chlorobenzylideneamino thiosemicarbazone, p‐itrobenzylideneamino thiosemicarbazone and p‐N,N ′‐dimethylminobenzylideneamino thiosemicarbazone. The structures of these compounds were characterised by elemental analysis, IR, ¹H NMR and UV spectral measurements. The antifouling properties of the compounds were evaluated through the incorporation of each compound in a marine coating system and testing the system in Alexandria Eastern Harbour water. The results are discussed in the light of the leaching rate of the compounds from their paint films, and their interaction with paint matrix.

Measures the rates of the copper (II)/steel cementation reaction in organic‐water mixture solvent at 25°C using an atomic absorption spectrophotometer. The relation between In C0/C and t in the absence of non‐aqueous solvent and at very diluted CuSO4 solution is given by In C0/C= k.A.t/V, while in the organic‐water mixture the data fit the equation of In C0lC= b+kAt/V. Finds that the rate constant of the cementation reaction increases with increasing the dielectric constant of the mixture. The rate of cementation increased in the order: water > methanol > ethanol > n‐propanol > 2‐propanol.

Although much work has been done on the rate of diffusion‐controlled corrosion under forced convection (moving solution), little has been done on the rate of diffusion‐controlled corrosion under natural convection which takes place in stagnant solutions. In diffusion‐controlled corrosion, the rate of corrosion is determined by the rate of transfer of the depolarizer or by the rate of removal of the corrosion products to or from the corroding surface respectively. In the case of stagnant solutions, transfer of the depolarizer to the corroding surface and removal of the corrosion products take place by diffusion and natural convection which arises from the density difference between the bulk solution and the interfacial solution, the interfacial solution being more dense than the bulk solution owing to the dissolution of the metal at the interface. This density difference result in a downward flow which enhances the rate of diffusion controlled corrosion. According to the hydrodynamic boundary layer theory the magnitude of natural convection depends on the physical properties of the solution us well as the geometry and orientation of the solid surface. Diffusion‐controlled metallic dissolution of vertical and horizontal surfaces has been studied earlier.

The rate of copper dissolution in presence of phosphoric acid‐formaldehyde mixtures were studied by measuring the limiting current which represents the rate of electropolishing. It is found that the rate of dissolution is decreased by increasing H₃PO₄ concentration, electrode height and mole fraction of formaldehyde. It is found that the decrease in the rate of dissolution ranges from 24 per cent to 63.88 per cent depends on the mole fraction of formaldehyde. The thermodynamic parameter ΔH* ΔG* ΔS* was calculated.

The rates of copper/zinc cementation reaction in isobutanol‐water mixture was measured at different temperatures using an atomic absorption spectrophotometer. The rate of cementation decreases with increasing the percentage composition of alcohol, and increases by increasing temperature and the rate of rotation. Thermodynamic parameters ΔH*, ΔG* and ΔS* were calculated.