This research has presented a solution to the problem faced by alloys: the corrosion problem, by reducing corrosion and enhancing protection by using an inhibitor (Schiff base). The inhibitor (Schiff base) was synthesized by reacting of the substrates materials (4-dimethylaminobenzaldehyde and 4-aminoantipyrine). It was diagnosed by infrared technology IR, where the IR spectrum and through the visible beams proved that the Schiff base was well formed and with high purity. The corrosion behavior of carbon steel and stainless steel in a saline medium (artificial seawater 3.5%NaCl) before and after using the inhibitor at four temperatures: 20, 30, 40, and 50 C° was studied by using three electrodes potentiostat. The corrosion behavior was studied by cathode and anode polarization through which all corrosion parameters were investigated which include: corrosion current icorr (1341× 10-7-5393 × 10-9A/cm2), corrosion potential Ecorr (-1.031--0.227 mV vs SCE) , corrosion rates CR (0.658-0.007 mm.y-1), inhibition efficiency %IE (92-98%), and energy activation barriers Ea (4.709-26.733 kJ/mole). The thermodynamic and kinetic properties of the corrosion behavior of these two metals under study, which include: enthalpy ∆H*(2.153-24.176 kJ/mole), entropy ∆S*(-197 -156 J/mole), and freeGibbs energy ∆G*(59.87-74.56 kJ/mole) before and after using the inhibitor, were also studied
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This study aimed to investigate the influence of longitudinal steel embedded tubes located at the center of the column cross-section on the behavior of reinforced concrete (RC) columns. The experimental program consisted of 8 testing pin-ended square sectional columns of 150×150 mm, having a total height of 1400 mm, subjected to eccentric load. The considered variables were the steel square tube sizes of 25, 51 and 68 mm side dimensions and the load eccentricity (50 and 150) mm. RC columns were concealed steel tubes with hollow ratios of 3%, 12% and 20% depending on tube sizes used. The experimental results indicated an improvement in the overall behavior of eccentric columns when steel embedded tubes are used. The maximum gain in
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The presence of antibiotic residues such as ciprofloxacin (CIPR) in an aqueous environment is dangerous when their concentrations exceed the allowable. Therefore, eliminating these residues from the wastewater becomes an essential issue to prevent their harm. In this work, the potential of efficient adsorption of ciprofloxacin antibiotics was studied using eco-friendly ZSM-5 nanocrystals‑carbon composite (NZC). An inexpensive effective natural binder made of the sucrose-citric acid mixture was used for preparing NZC. The characterization methods revealed the successful preparation of NZC with a favorable surface area of 103.739 m2/g, and unique morphology and functional groups. Investigating the ability of NZC for adsorbing CIPR antibioti
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The conception and experimental assessment of a removable friction-based shear connector (FBSC) for precast steel-concrete composite bridges is presented. The FBSC uses pre-tensioned high-strength steel bolts that pass through countersunk holes drilled on the top flange of the steel beam. Pre-tensioning of the bolts provides the FBSC with significant frictional resistance that essentially prevents relative slip displacement of the concrete slab with respect to the steel beam under service loading. The countersunk holes are grouted to prevent sudden slip of the FBSC when friction resistance is exceeded. Moreover, the FBSC promotes accelerated bridge construction by fully exploiting prefabrication, does not raise issues relevant to precast co
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Schiff bases (SBs) based on amino acid derivative stand for multipurpose ligands that formed by condensing amino acids with carbonyl groups. They are significant in pharmaceutical and medical areas due to their widespread biological actions such as antiseptic, antifungal, along with antitumor actions. Transition metallic complexes resulting from SB ligands with biological activity were extensively experimented in the literature. In this article, we review, in details, about synthesizing and biological performances of SBs along with its complexes.
SYNTHESIS, AND ANTIOXIDANT ACTIVITY STUDIES OF BINUCLEAR COMPLEXES CONTAINING SCHIFF BASE LIGAND
Chitosan-schiff base with three different ratios of para-Dimethyl aminobenzaldehyde& chitosan Schiff base hydrogels have been prepared for controlled drug release study. The synthesized chitosan Schiff base and chitosan Schiff base hydrogel were characterized by FT-IR, UV-Visible, SEM, analysis. Swelling properties of the hydrogel were investigated at three different media pH (2, 7, 10). The swelling degree varied with the pH, amount of crosslinking agent glutaraldehyde and with the amount of paraDimethylaminobenzaldehyde for the hydrogels. All hydrogels were used for controlled drug release system. Aspirin was used as model drug, in three different buffer solution (2, 7, 10) as release media. The rate of release of drugs in the pH2 is m
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Schiff base of chitosan with Para-Dimethyl aminobenzaldehyde /PVA-Ag Nanocomposite have been prepared as antimicrobial polymer. The prepared chitosan Schiff base and chitosan Schiff base / PVA-Ag nanocomposite were characterized by FT-IR, SEM analysis and biological activity. The nanocomposite showed good activity against different types of bacteria.
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Rates of zinc consumption during cathodic protection of a copper pipeline carrying saline water were measured by the loss in weight technique. The study of sacrificial anode cathodic protection of short copper tube using zinc strip extended axially in the pipe revealed that : (i) The increase of zinc consumption with time of exposure (1-3 h's) at different flow rates (turbulent flow) (300-600 l/hr) while the temperature , solution concentration and the pH were fixed at 20ºC, 3.5%wt NaCl, and pH=8 respectively in absence and presence of bacteria.(ii)Increase of zinc consumption with flow rates (300-600 l/hr) at different temperatures (10-40ºC) while solution concentration and time of exposure were fixed at 3.5 %wt NaCl and 3hr's respective
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