Electrochemical studies of mild steel corrosion inhibition in sulfuric acid chloride by aniline

The corrosion behavior of mild steel in dilute hydrochloric acid under the inhibiting action of various concentrations of aniline was studied using the weight loss and linear polarization resistance technique. The efficiency of the inhibitor increased with the increase in the inhibitor concentration. The results obtained reveal that aniline performed effectively as a corrosion inhibitor. The adsorption mechanism indicates mixed molecular interaction from values of Gibbs free energy. The values of the inhibition efficiency calculated from the two tech- niques are in reasonably good agreement. The adsorption of the inhibiting com- pound was found to obey Langmuir, Frumkin and Freudlich adsorption isotherms. The mechanism of inhibition was discussed in the light of the chemical structure of the inhibiting compound and their adsorption on steel surfaces in relation to the potentiodynamic parameters

Inhibition Effect of N, N'-Dimethylaminoethanol on the Corrosion of Austenitic Stainless Steel Type 304

The effect of N,N'-dimethylaminoethanol on the corrosion of austenitic stainless steel type 304 in 3M H2SO4 has been studied by weight-loss method and linear polarization measurement in different concentrations of the compound. The inhibition efficiencies of the inhibitor compound on the corrosion of the stainless steel were evaluated through assessment of the anodic and cathodic polarization curves of the alloy, the spontaneity of the electrochemical process, inhibition mechanism and adsorption isotherm. The inhibitor efficiency increased with increase in the inhibitor concentration. Results obtained reveal that the inhibitor performed effectively on the stainless steel providing good protection against pitting and uniform corrosion in the chloride containing acidic solutions. The compound act through physiochemical mechanism on the stainless steel surface and obeyed Langmuir adsorption isotherm. The values of the inhibition efficiency calculated from the two techniques are in reasonably good agreement. Polarization studies showed that the compounds behave as mixed type inhibitor in the aggressive media

Structure and magnetic properties of nanogranular composites CoFeZr-alumina

The 5 to 15 μm thick nanocomposite films (Coo.45Fe0.45Zr0.10)x(Al2O3)1-x with 30 < x < 65 at.% sputtered in a chamber evacuated with pure Ar gas were studied using Mössbauer spectroscopy, magnetization, complex magnetic permeability, and magneto-force microscopy (MFM) measurements. In particular, the films with x < 40 at.% displayed superparamagnetic state at room temperature (the lack of sextets in Mössbauer specta, non-hysteresis character of the magnetization curves, invariability of real μ’ and imaginary μ’’ parts of magnetic permeabilities with x and high resistivity. Near the percolation threshold ( x ≈ 40 - 45 at.%) Mössbauer specta displayed features of the ferromagnetic sextet and the values of μ’ and μ’’ increased, approaching the maximum, as x increasing due to the decrease of inter-particle distances. Moreover, effects of dipole-dipole and exchange interactions of the nanoparticles resulted in the nucleation of the magneto-ordered granules (magnetoclusters) including a few metallic nanoparticles. The MFM allowed to visualizing the presence of magnetic labyrinth-like magnetic contrast that was formed by the metallic nanoparticles near the percolation threshold. At x > 45 at.% the films behave like the “bulk” ferromagnetic sample with occasional inclusions of dielectric phase. 1. INTRODUCTION At present time high interest is given to granular composite materials, which consist of metallic nanosized particles randomly distributed within a dielectric matrix, because they represent nearly ideal systems for the study of nanostructured materials with a big change of their composition. For the first time, such materials (named as cermets) were manufactured at the beginning of seventies of the last century and during that decade the main concepts concerning the electrical and magnetic properties of composites were stated [1-5]. The interest of these materials was renewed in the nineties, of the previous century, because of their possible applications in the magnetic field sensors and as magnetic recording media. The study of magnetic properties of iron, cobalt or nickel nanoparticles embedded into a dielectric matrix has shown [6] that reduction of volume fraction of the metallic phase below the percolation threshold xC resulted in metallic granules becoming a singledomain and the nanocomposite as a whole displays superparamagnetic properties at room te

Modelling of Training Program Development for Supply Chain Management Business Project Development: Practical Research Results

Abstract- the article discusses the issues related to information-analytical support of the management/strategy development for international supply chain management business projects within training program development (level 2 of IEBP management model system): the selection of the key meta-competences , forms and formats of project-based learning, the most preferred for the main task types characteristic of the attractive activities, selected during HR-organization strategy development for IEBP management (they provide a brief description of the problem statement for this level). The article describes in detail the development of MAI-hierarchies (general preliminary and refined in VS-modification) developed for this level. They provide calculations of multi-expert assessments during the implementation of the supply chain management business project "New supply chain management", and analyze the main problems associated with the made choice made. A brief overview of additional (corrective) models of the supply chain management process optimization/rationalization is provided for this level. It was founded that governments around the world need to play a prominent role in developing strategies to protect supply chains for the future and put in place more robust disaster recovery plans, including relevant stockpiles, to enable more resilient outcomes