Electrochemical and Spectroscopic Study on the Corrosion of Ti–5Al and Ti–5Al–5Cu in Chloride Solutions

El‑Sayed M. Sherif,Fahamsyah H. Latief,Hany S. Abdo,Nabeel H. Alharthi 대한금속·재료학회 2019 METALS AND MATERIALS International Vol.25 No.6

In this study, manufacturing of Ti–5Al and Ti–5Al–5Cu alloys were accomplished employing mechanical alloying technique. The corrosion resistance in 3.5 wt% NaCl solution of Ti–5Al and Ti–5Al–5Cu alloys was investigated using cyclicpolarization (CPP), electrochemical impedance spectroscopy (EIS) and chronoamperometric current–time measurements. The corroded surfaces of Ti–5Al and Ti–5Al–5Cu were examined by the use of a scanning electron microscopy and energydispersive X-ray spectroscopy. It is found that Ti–5Al suffers both uniform and pitting corrosion, particularly with prolongingthe time of exposure period in the chloride solution. While, the addition of Cu, Ti–5Al–5Cu alloy, increases the intensity ofuniform corrosion and decreases the probability of pitting attack. Prolonging the immersion time to 48 h before measurementdecreases the corrosion of Ti–5Al alloy, while increases the corrosion of Ti–5Al–5Cu.

Adsorption of lisinopril and chlorpheniramine from aqueous solution on dehydrated and activated carbons

El-Said I. El-Shafey,Haider A. J. Al-Lawati,Wafa S. H. Al-Saidi 한국탄소학회 2016 Carbon Letters Vol.19 No.-

Date palm leaflets were used as a precursor to prepare dehydrated carbon (DC) via phosphoric acid treatment at 150°C. DC, acidified with H3PO4, was converted to activated carbon (AC) at 500°C under a nitrogen atmosphere. DC shows very low surface area (6.1 m2/g) while AC possesses very high surface area (829 m2/g). The removal of lisinopril (LIS) and chlorpheniramine (CP) from an aqueous solution was tested at different pH, contact time, concentration, and temperature on both carbons. The optimal initial pH for LIS removal was 4.0 and 5.0 for DC and AC, respectively. However, for CP, initial pH 9.0 showed maximum adsorption on both carbons. Adsorption kinetics showed faster removal on AC than DC with adsorption data closely following the pseudo second order kinetic model. Adsorption increases with temperature (25°C–45°C) and activation energy (Ea) is in a range of 19–25 kJ mol/L. Equilibrium studies show higher adsorption on AC than DC. Thermodynamic parameters show that drug removal is endothermic and spontaneous with physical adsorption dominating the adsorption process. Column adsorption data show good fitting to the Thomas model. Despite its very low surface area, DC shows ~70% of AC drug adsorption capacity in addition of being inexpensive and easily prepared.

Antioxidative and anti-α-amylase activities of four wild plants consumed by pastoral nomads in Egypt

SJ Hossain,M El-Sayed,H Aoshima 경희대학교 융합한의과학연구소 2009 Oriental Pharmacy and Experimental Medicine Vol.9 No.3

In this study, four plants grown naturally in Egypt that are usually consumed by pastoral nomads were screened for their total phenolic contents, antioxidative, and anti-α-amylase activities. Dried powder of plant’s part was extracted in absolute or 70% ethanol. A polar extract of Panicum turgidum (PTPE) had the highest total polyphenol content {92.5 mg gallic acid equivalents (GAE)/g}, followed by an alkaloid extract of Withania somnifera (WSAlk; 77.5 mg GAE/g), and an ethanol extract of Leptadenia pyrotechnica (LPEE; 59.1 mg GAE/g). By employing different assays such as DPPH radical scavenging, reducing power, Fe+ chelating, H2O2 scavenging and total antioxidant capacity, it was shown that PTPE, WSEE (ethanol extract of W. somnifera), WSAlk and LPEE had promising antioxidant activity, though, their potency varied according to the different tests. WSAlk had the highest level of α-amylase inhibition (40.2%) in vitro, followed by WSEE (30.5%). Therefore, it can be concluded that these plants, especially extracts of PTPE, and WSAlk are beneficial to physiological health, and could be used in food and pharmaceutical industries to prepare dietary supplements, functional foods or food preservatives. In this study, four plants grown naturally in Egypt that are usually consumed by pastoral nomads were screened for their total phenolic contents, antioxidative, and anti-α-amylase activities. Dried powder of plant’s part was extracted in absolute or 70% ethanol. A polar extract of Panicum turgidum (PTPE) had the highest total polyphenol content {92.5 mg gallic acid equivalents (GAE)/g}, followed by an alkaloid extract of Withania somnifera (WSAlk; 77.5 mg GAE/g), and an ethanol extract of Leptadenia pyrotechnica (LPEE; 59.1 mg GAE/g). By employing different assays such as DPPH radical scavenging, reducing power, Fe+ chelating, H2O2 scavenging and total antioxidant capacity, it was shown that PTPE, WSEE (ethanol extract of W. somnifera), WSAlk and LPEE had promising antioxidant activity, though, their potency varied according to the different tests. WSAlk had the highest level of α-amylase inhibition (40.2%) in vitro, followed by WSEE (30.5%). Therefore, it can be concluded that these plants, especially extracts of PTPE, and WSAlk are beneficial to physiological health, and could be used in food and pharmaceutical industries to prepare dietary supplements, functional foods or food preservatives.

Efficacy of Nile tilapia (Oreochromis niloticus) juveniles and spinosyns bioinsecticides against aquatic stages of Culex pipiens: An experimental study

Mohamed Ibrahim A.,Fathy Mohamed,Farghal Ahmed I.A.,Temerak Sobhy A.H.,Sayed Alaa El-Din H. 한국응용곤충학회 2021 Journal of Asia-Pacific Entomology Vol.24 No.1

The mosquito Culex pipiens is the most widely distributed dipteran species in all regions of Egypt and the principal vector of Wuchereria bancrofti and certain arboviruses in human beings. For controlling C. pipiens vector, biological tools (e.g., larvivorous fish and bioinsecticides) are more potent and safer options to the environment, human beings, and beneficial organisms than chemical pesticides. The efficiency of O. niloticus juveniles as predatory fish species and two bioinsecticides, spinosad 24% and spinetoram 12%, was investigated against the C. pipiens developmental stages in the laboratory. The first trial evaluated the predatory efficacy of small-sized O. niloticus (2.1–2.6 cm; 250–315 mg) and large-sized O. niloticus (2.5–3.2 cm; 250–315 mg) against the 3rd larvae and pupae of C. pipiens. This is the first report in Egypt confirming the predation potential of O. niloticus as efficient predatory fish against the immature C. pipiens. Large-sized O. niloticus predated a greater number of 3rd of C. pipiens larvae and pupae than the small-sized ones. Furthermore, the daily consumption of C. pipiens larvae by small- and large-sized O. niloticus was significantly higher than the pupae. The second trial assessed the toxicity efficacy of spinosad 24% and spinetoram 12% against C. pipiens larvae and pupae. The results confirmed that the tested bioinsecticides showed higher potency toward C. pipiens larvae than pupae after exposure for 24 h and 48 h. Spinosad was more toxic toward 3rd C. pipiens larvae (LC 50 = 0.013 and 0.003 mg/L) and pupae (LC 50 = 320.69 and 44.28 mg/L) than spinetoram after 24 and 48 h. Herein, O. niloticus juveniles (as promising native predatory fish) and spinosyns bioinsecticides were more effective against C. pipiens in the larval stage than in the pupal stage. In conclusion, Nile tilapia juveniles and biorational compounds, spinosad 24% and spinetoram 12%, might be considered as promising and favorable environmental biological agents for controlling C. pipiens in Egypt. However, further trials are needed to investigate the potential of these agents in the control of this mosquito vector under field conditions.

Magnetic Properties of La3+-ion-doped Polycrystalline Z-type Hexaferrite Powders Synthesized via the Co-precipitation Method

M. M. Rashad,M. Rasly,I. A. Ibrahim,H. M. El-Sayed,A. A. Sattar 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.63 No.3

Co2Z-type hexagonal ferrite powders doped with La3+ ions (Ba3−XLaxCo2Fe24O41 where x =0.0, 0.05, 0.10 and 0.15) were prepared using a co-precipitation method. The results revealed thatsingle-phase Co2Z-type ferrite was formed from the precipitated precursor in the presence of sodiumdodecyl sulfate (SDS) as an anionic surfactant. The obtained precursor was preheated at 600 ℃ for4 h then post annealed at 1300 ℃ for 6 h. The crystallite size increased with increasing of La3+-ion molar ratio. The microstructure of the formed powders appeared to be a hexagonal-plateletlikestructure. The DC resistivity of the obtained Co2Z decreased with increasing La3+ content. The saturation magnetization (Ms = 53.7 - 55.5 emu/g) was slightly increased with increasingsubstitution of La3+ ion. Moreover, two resonance frequency peaks were observed through theimaginary part of complex magnetic permeability; meanwhile, a decrease in the real part of thecomplex magnetic permeability was observed through the X-band frequencies.

Memory response in elasto-thermoelectric spherical cavity

El-Attar, Sayed I.,Hendy, Mohamed H.,Ezzat, Magdy A. Techno-Press 2020 Coupled systems mechanics Vol.9 No.4

A mathematical model of electro-thermoelasticity subjected to memory-dependent derivative (MDD) heat conduction law is applied to a one-dimensional problem of a thermoelectric spherical cavity exposed to a warm stun that is an element of time in the presence of a uniform magnetic field. Utilizing Laplace transform as an instrument, the issue has been fathomed logically within the changed space. Numerical inversion of the Laplace transform is carried for the considered distributions and represented graphically. Some comparisons are shown in the figures to estimate the effects of MDD parameters and thermoelectric properties on the behavior of all considered fields.

Imparting Durable Ultraviolet Protection to Polyamide 6 Fabric

H. El-Sayed,A. Abou El-Kheir,L. K. El-Gabry,K. Haggag 한국섬유공학회 2019 Fibers and polymers Vol.20 No.10

Deterioration of polyamide 6 fabrics upon exposure to ultraviolet radiation for a long time is an acute dilemma. Imparting ultraviolet protection to polyamide fabrics is of prime importance from the performance and economic point ofviews. In this investigation, polyamide 6 fabrics were modified with an environmentally friendly product (sericin) in presenceor absence of crosslinking agents; namely citric acid or epichlorohydrin using pad-dry-cure technique. Topographicalinvestigation of the used sericin powder was conducted using transmission electron microscopy (TEM). The morphologicalstructure of treated as well as untreated fabrics was investigated using high resolution field emission scanning electronmicroscope (FE-SEM). The alteration in some physico-mechanical characteristics of the treated polyamide 6 fabrics; Viz. bending stiffness, burst test, degree of yellowness, and moisture regain were assessed. The treated polyamide fabrics weredyed with acid and reactive dyestuffs. The colour strength and washing fastness for dyed fabrics with both acid and reactivedyes were assessed. The photo-protection against UV light of the said fabrics were evaluated. The treated fabric exhibitedexcellent UV protection without significant discrepancy in their inherent physico-mechanical properties.

AUTOMOTIVE FORMABILITY SIMULATION PROCESS FOR EARLY DESIGN PHASES

EL-SAYED J.,KIM H.,FRUTIGER R.,LIU W. The Korean Society of Automotive Engineers 2005 International journal of automotive technology Vol.6 No.3

Formability simulation of automotive panels at early design phases can reduce product and tooling development time and cost. However, for the simulation to be effective in leading the design process, fast and reliable results should be achieved with limited design definition and minimum modeling effort. In this paper, nonlinear finite element analysis is used to develop an automated process for the formability simulation of automotive body panels at early design phases. Due to the limited design definition at early design phases, the automated simulation process is based on the plane strain analysis for selected number of typical sections along the panel. Therefore, an entire panel can be analyzed with few sections. The state of plane strain can be easily induced, during simulation through symmetry and applied boundary conditions that simplify the modeling process. To study the reliability and effectiveness of the developed simulation process, the analytical results are compared with measured results of production automotive body side panels. The comparison demonstrates that the developed simulation process is reliable and can be effective for analyzing sheet metal formability, in early vehicle development phases.

Molluscicidal Activity and Clinico-pathological Effect of Agave lophantha

El-Sayed, M.M.,Abdel-Hadi, M.,El-Nahas, H.A. The Pharmaceutical Society of Korea 1991 Archives of Pharmacal Research Vol.14 No.1

Dry powder and different extracts of Agave lophantha were tested against Biomphalaria alexandrina. The results showed that the butanol extract has high molluscicidal activity. The activity of the dry powder has been found to be stable under the effect of some simulated field conditions. Also the toxicological effect of the plant on mice was tested through determination of certain parameters such as total protein, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and acid phosphatase enzymes as well as histopathological study on liver and kidney.

Fabrication of self-assembled RGD layer for cell chip to detect anticancer drug effect on HepG2 cells

El-Said, W.A.,Yea, C.H.,Kim, H.,Choi, J.W. Elsevier 2009 Current Applied Physics Vol.9 No.2

HepG2 cells have been immobilized on nanoscale self-assembled synthetic oligopeptide modified chip surface and subsequently used for anticancer drug screening. Nanoscale controlled self-assembled peptide layer was investigated by AFM (Atomic Force Microscopy). The immobilization of HepG2 cells on nanoscale controlled surface was investigated by using Raman spectroscopy. HepG2 cells were grown on peptide modified gold surface acting as working electrode. The AFM investigation of the oligopeptide modified surface showed excellent agreement with the nanoscale nature of the peptide modification, and the voltammetric response of HepG2 cells on this surface towards an anticancer drug showed a linear relationship with the cell number. As an application, electrochemical detection of anticancer drug effect of HepG2 cells was shown. These results indicate that RGD (Arg-Gly-Asp) peptide self-assembled layer mediated the cell immobilization technique and the voltammetric signal analysis system can be applied to construct a cell chip for diagnosis, drug detection, and on-site monitoring.