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The University of Technology in Baghdad addresses problems related to the corrosion of metals. In the present investigation, a thiophene derivative, namely, 2-acetylthiophene thiosemicarbazone (2-AT), was synthesized and examined as a corrosion inhibitor for mild steel in a 1-M hydrochloric acid environment by using weight loss and scanning electron microscopic techniques. The inhibition efficiency of this inhibitor increases with increase in concentration, which offered an inhibition efficiency up to 96%. It was found that the inhibition efficiency decreases with long immersion time. The temperature effect on the inhibition performance was studied at various immersion times and revealed that the inhibition efficiency decreases with increasing temperature. The adsorption of the inhibitor on the surface of mild steel in the corrosive environment followed the Langmuir isotherm. The results of scanning electron microscopy (SEM) reveal that the 2-AT molecules confirmed the presence of a protective layer on the surface of a mild steel sample. The density-functional theory as a quantum modeling technique which is used to study the electronic structure reveals that the obtained findings were found to be consistent with the experimental results.

Several methods are currently used to calculate the values of voltage, current, and power of a solar cell. A new method is suggested to numerically find these values using the popular methods Newton Raphson method (NRM) and the three-step method (TSM) at different values of load resistance R. Equation based on the equivalent circuit of a solar cell, so all calculations is performed in a MATLAB at room temperature. The obtained results of this new method were presented and compared with NRM. Additionally, a single diode model of a solar cell was demonstrated.

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The transport of heavy crude oil from the head-well to the refinery plants is an attractive factor as its production is currently increasing around the world. Though the higher viscosity increases trouble in the piping transportation and production from the reservoir, for these reasons, this study focuses on the dilution method to reduce its viscosity using toluene, dimethyl ketone (DMK) and a mixture of (50/50 vol. %) toluene/dimethyl ketone as a dilutes solvents with different weight fraction (0, 5, 10 and 15 wt. %) at 298.15 K. The heavy oil used collected from Amara oil field, south of Iraq. The viscosity was measured by Brookfield viscometer over a range of shear rates (0-42s-1). On another way to understand the effect of temperature, the better result for weight fraction of solvents in viscosity reduction of heavy oil was investigated under different temperatures (298.15, 308.15 and 318.15 K). The obtained results showed dilution of heavy oil samples with toluene, DMK and a mixture of (50/50 vol. %) toluene and DMK is an effective method for reducing the viscosity. Moreover, the temperature has a significant effect on the degree of viscosity reduction in the presence of the diluents. However, the higher DVR was noticed about 87.17 % at 15 wt.% of the mixture (50/50 vol. %) toluene + DMK at 318.15 K and shear rate 42 s-1. Tthe relevant results attribute to an aromatic characteristic of toluene which allows interferes in the asphaltene aggregation.