Molecular dynamics simulations and quantum chemical calculations for the adsorption of some imidazoline derivatives on iron surface

The molecular dynamic (MD) simulation and quantum chemical calculations for the adsorption of [2-(2-Henicos-10- enyl-4,5-dihydro-imidazol-1-yl)-ethyl] methylamine (HDM) and 2-(2-Henicos-10-enyl-4,5-dihydro-imidazol-1-yl)-ethanol (HDE) on iron surface was studied using Materials Studio software. Molecular dynamic simulation results indicate that the imidazoline derivative molecules uses the imidazoline ring to effectively adsorb on the surface of iron, with the alkyl hydrophobic tail forming an n shape (canopy like covering) at geometry optimization and at 353 K. The n shape canopy like covering to a large extent may prevent water from coming in close contact with the Fe surface. The quantum chemical calculation based on the natural atomic charge, the frontier molecular orbital and the Fukui indices values and plots shows the active sites of the molecules to be mainly the N=C-N region in the imidazoline ring, others include the nitrogen and oxygen heteroatoms in the pendant part and the double bonded carbon atoms in the hydrophobic tail of the imidazoline derivative molecules. The quantum chemical calculations also reveal that the amine group in HDM and the hydroxyl group in HDE which is attached to the imidazoline ring do not result in a significant increase in the HOMO nor the LUMO density which can aid adsorption. HDM has a lower energy gap of 4.434 eV and 3.824 eV, a higher EHOMO of -4.273 eV and -4.152 eV and a higher global softness of 0.45 and 0.52 compared to HDE which have an energy gap of 4.476 eV and 4.084 eV, a EHOMO of -4.349 eV and -4.607 eV and a global softness of 0.45 and 0.49 at geometry optimization and at 353 K. The adsorption ability of the molecule is given as at geometry optimization HDM > HDE and at 353 K HDM > HDE. Theoretically HDM is a better inhibitor than HDE. The adsorption ability of the molecule is in line with the binding energy at the temperature studied.Keywords: Molecular dynamic simulation; iron surface; adsorption; imidazoline derivatives; quantum chemical calculation

Atmospheric corrosion of mild steel in the Niger Delta region of Nigeria. Part 1: Characterization of the Calabar, Cross River State environment

The atmospheric corrosion of Calabar, Cross River State environment has been investigated for 12 months using weight loss technique. The extent of pollution of the environment was also determined via measurements of the precipitation and air quality parameters. Apart from the suspended particulate matter (SPM) (113-630 &mu;g/m3) and NO2 (> 0.06 ppm) values, other measured atmospheric parameters (CO 5.0, conductivity < 60 &mu;Scm-1, TDS < 41.48 mg/l, TSS < 0.05 mg/l, NO3 - < 3.00 mg/l, SO4 2

Intensification and diversification of banana production systems: key drivers for increased income and food and nutritional security in the Great Lakes region

Peer Revie

DNA from Plant leaf Extracts: A Review for Emerging and Promising Novel Green Corrosion Inhibitors.

With growing global awareness and concern for environmental protection through the use of less hazardous and environmentally-friendly extracts of plant origin, there has been a plethora of green corrosion inhibitors research with far reaching contributions to the science of corrosion prevention and control. Attention has increasingly turned towards green corrosion inhibitors, compounds of natural origin with anti-oxidant activity towards metals and their alloys. Green inhibitors have been investigated for their corrosion and adsorption properties with good results. The findings from these research works provide evidence of the adsorption behavior of green inhibitors which was confirmed by the adsorption isotherms that were proposed. Adsorption is the first step of any surface reaction and since corrosion is a surface phenomenon the effectiveness of green corrosion inhibitors is related to their ability to adsorb on metal surfaces. This review proposes the potential of plant dna as an emerging and promising novel inhibitor for mild steel. It begins with a list of plants that have been used in studies to determine corrosion inhibition properties and moves on to establish the adsorption behavior of bio macromolecules; protein, polysaccharides (chitosan) and dna. It reviews studies and investigation of dna interaction and adsorption on inorganic surfaces before focusing on the use of salmon (fish) sperm dna and calf thymus gland dna as green corrosion inhibitors for mild steel. It concludes that plant dna is a promising candidate for green corrosion inhibitor given the similarity between the plant and animal dna structure and function, and the fact that the use of plant is more environmentally sustainable than animal-based produc

<b>Inhibition of the acid corrosion of aluminium by some derivatives of thiosemicarbazone</b>

The inhibition of corrosion of aluminium in HCl solution by some derivatives of thiosemicarbazones has been studied using weight loss and hydrogen evolution techniques. The thiosemicarbazone derivatives used are 2-acetyl pyridine-(4-phenylthiosemicarbazone) (PTSC), 2-acetyl pyridine-(4-phenyl-iso-methylthiosemicarbazone) (PIMTSC) and 2-acetyl pyridine-(4-phenyl-iso-ethylthiosemicarbazone) (PIETSC). The inhibition efficiency depended on the compounds concentration until at very low concentration studied where they reversed their functions and became accelerators. Kinetic treatment of the results gave a first order type of mechanism. The results reported in this paper elucidate the effects of inhibitor concentration, temperature and the molecular structure on the inhibition efficiency