Advanced Materials Research Vol. 787

Abstract: The corrosion inhibition characteristics of the synthesized (I, II and III) nonionic surfactants on carbon steel corrosion in 1 M acid chloride have been investigated at 30 oC by potensiodynamic polarization. The obtained results show that compound I has the best efficiency at concentration 0.08 mmol/L while compound III is the best inhibitor at higher concentrations. The surface parameters of each synthesized surfactant were calculated from its surface tension including the critical micelle concentration (CMC), effectiveness of surfactant (π), maximum surface excess (Γ_max) and the minimum surface area (A_min).

Abstract: The corrosion inhibition efficiency of carbon steel pipelines in 1M HCl by the synthesized hexatriethyleneamine derivatives potensiodynamic polarization 30 oC. The results showed that all synthesized inhibitors were good inhibitors and their inhibition efficiencies were significantly increased with increasing concentration. The surface activity were calculated from its surface tension measurements including the critical micelle concentration (CMC), effectiveness of surfactant (π), maximum surface excess (Γ_max) and the minimum surface area (A_min).

Abstract: At present, high temperature oil wells are known as the most problematic for cementing operation due to limitations of polymer. The polymers are significantly used as mutlifunctional additives for improving the properties of cement slurry. At high temperature, viscosity of polymer decreases and unable to obtained desired properties of cement slurry. It becomes then major cause of fluid loss and gas migration during cementing operations. Thus, it necessitates for polymers that can able to enhance viscosity of slurry at elevated temperatures. This paper is aiming to study Hydroxypropylmethylcellulose (HPMC) polymer at high temperature that is able to increase the viscosity at elevated temperature. In response, experiments were conducted to characterize rheological properties of HPMC at different temperatures (30 to 100 °C). Then it was incorporated as multifunctional additive in cement slurry for determining API properties (fluid loss, free water, thickening time and compressive strength). It was observed that HPMC polymer has remarkable rheological properties that can have higher viscosity with respect to high temperatures. The best concentration of HPMC was found from 0.30 to 0.50 gallon per sack. This concentration showed minimal fluid loss, zero free water, high compressive strength and wide range of thickening time in cement slurry. The results signified that HPMC polymer is becoming multifunctional additive in cement slurry to improve the API properties of cement slurry and unlock high temperature oil wells for cementing operations.

Abstract: Polyetherimide (PEI) with excellent solvent resistance and thermal resistance is a good membrane material which is studied in detail. PEI ultrafiltration membrane with low molecular weight cut-off is prepared by phase inversion method in this work. The membrane showed high resistance to PEG1000 which can be used in wastewater treatment with organic solvent.

Abstract: The microstructural evolution behavior of Mg-3Si-1.70Sn alloys during semisolid isothermal heat treatment was investigated by optical microscopy observations in the present study. With the holding time increasing, the grains evolve to be more spheroidal and 15min is adequate for the alloy to be spheroidized, after this coarsening begins to happen. The amount of the liquid islands inside α-Mg grains decreases and that of the liquid phase at the grain boundaries increases with the prolonged holding time. Moreover, the morphology of eutectic Mg₂Si phases changes from the Chinese script and/or long-fiber shape to short fiber or spherical shapes during semisolid isothermal heat treatment, which can be attributed to the Rayleigh shape instability.

Abstract: Colorectal cancer is a malignant tumor, one of the main types of cancer which produces a large number of deaths each year in many countries around the world. The main objective of this work is to employ various bioinformatics tools to perform docking of the transitional metal complexes (Zn (II), Co (II), Cu (II), Fe (II), Ni (II)) with cholic acid (AC) as ligand against Aurora A Kinase (RCSB Protein Data Bank code: 2X6E). Molegro Virtual Docker (MVD) was used for the docking process. The molecular docking score and the values of the statistic parameter Root Mean Square Deviation (RMSD) are presented in Table 1. The results obtained in this study serve to design new complex combinations with potential action against Aurora A Kinase inhibitor.

Abstract: Well defined polychloroprene has been synthesized by reversible addition fragmentation chain transfer (RAFT) polymerization with 2-(ethoxycarbonyl) prop-2-yl dithiobenzoate (EPDTB) as RAFT agent, AIBN as initiator, Chloroprene as monomer. Polymerization with two different feed ratios of monomer to RAFT agent were carried out. The sampling products at different reaction times were characterized using GPC and ¹H-NMR. The GPC results demonstrated the molecular weight distributions (M_w/M_n) were narrow, and the number average molecular weight (M_n) was developed linearly with monomer conversion. All the characteristic signals of polychloroprene with the EPDTB as terminal groups were clearly observed in the ¹H-NMR spectrum. In addition, the chain-extended polymers were also obtained successfully using the macro-RAFT agent, which indicated the active nature of the chain end.

Abstract: Self-assembly behavior of an cationic amphiphilic triblock copolymer Q-PVBC -b-PS-b-Q-PVBC in DMF/water and DMF/methanol were studied. Well defined triblock copolymer PVBC-b-PS-b-PVBC was synthesized by RAFT polymerization and the cationic amphiphilic block copolymers Q-PVBC-b-PS-b-Q-PVBC was obtained by the quaternization of hydrophobic precursors with triethylamine. It is concluded that that selective solvents had a great effect on the self-assemble morphologies of the polymer. Comparing to the micelles treating water as the selective solvent, the aggregates using methanol were irregular spheres and had larger diameter.

Abstract: The paper focuses on design and verification of mix-design of lightweight concrete with alkali-activated matrix with lightweight aggregate Liapor. Alkali-activated matrix was designed on the basis of ground metakaoline and micronized limestone. Mixes of concrete with alkali-activated matrix and lightweight porous aggregate Liapor of size fraction 8 mm were designed and their rheological and physico-mechanical properties were tested. To reduce shrinkage and to increase resistance to high temperatures, dispersed polypropylene fiber reinforcement was used and testing specimens made from this concrete with alkali-activated matrix were exposed to thermal load and tested.

Abstract: Recently friction stir processing (FSP) was developed as a generic implement for microstructural modification based on the principles of FSW using a rotating tool inserted in a monolithic work piece which provides frictional heating and mechanical mixing. In this paper, the microstructural evolution characteristics of nugget zone were investigated during friction stir processing (FSP) of pure copper. Pure copper plates were friction stir processed to the depth of 3.4 mm at different process conditions by varying the traverse speed from 30 to 120 mm/min at rotation speeds of 400 and 600 rpm..Defects were observed in rotational speed of 400 rpm. Grain size of NZ depended significantly on plastic deformation and heat input value. By increasing traverse speed at constant rotational speed of 600 rpm grain size of the nugget zone decreased and the hardness increased. Ultimate tensile strength increased with decrease in grain size. FSP was found as an effective method to develop fine-grained microstructure in copper plates.