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.

Alleviation of salt stress in  Triticum aestivum by biopriming with  Phanerochaete chrysosporium

Hanan El-Sayed Dief,El-Sayed A. Hashem,Salwa Fawzan,Ashraf S. A. El-Sayed 한국작물학회 2021 Journal of crop science and biotechnology Vol.24 No.1

Wheat is one of the most important cereals, vital basic crop in Egypt, covering approximately 32.6% of the total winter land. However, sensitivity to abiotic stress especially salinity is one the major current hurdles that reduce the global yield of this crop. Plant biopriming with fungi is the recent technology that might alleviate the salt stress eff ect. Thus, the objective of this work was to examine the eff ect of Triticum aestivum grains biopriming with Phanerochaete chrysosporium on the response of wheat to salt stress. From the physiological and biochemical parameters, biopriming of wheat grains with P. chrysosporium significantly alleviates the salt stress and markedly increases the growth parameters, photosynthetic pigments and osmolytes (soluble sugars, soluble protein and proline) contents. In addition, it alleviates the oxidative damage, as indicated by the lower accumulation of malondealdehyde and increasing the activity of antioxidant enzymes; superoxide dismutase, catalase, and ascorbate peroxidase in wheat seedlings. Results indicate the potential of using P. chrysosporium biopriming for reducing the deteriorating eff ects of salinity.

Bisphosphonate’s effect on the tongue in adult male albino rats and the possible protective role of rutin: light and scanning electron microscopic study

Dalia El-sayed El-ghazouly(Dalia El-sayed El-ghazouly ),Rania Ibrahim Yassien(Rania Ibrahim Yassien ) 대한해부학회 2024 Anatomy & Cell Biology Vol.57 No.1

Alendronate sodium (ALS) is a nitrogen-containing bisphosphonate used for the treatment of different bone disorders. However, its adverse effect on oral soft tissue has been detected. Rutin (RUT) is natural flavonoid with antioxidant and anti-inflammatory properties. This work aimed to investigate the possible effect of ALS on the tongue of adult male albino rats and to evaluate the possible protective role of RUT. Forty adult male albino rats were equally divided into four groups: group I (control), group II (RUT): Received RUT 50 mg/kg, group III (ALS): Received ALS 1 mg/kg, group IV (ALS+RUT): Received ALS and RUT with the same doses as pervious groups. The drugs were given once daily for 5 weeks. Tongue specimens were taken and processed for light and scanning electron microscopic inspection. ALS treated group revealed structural changes in the tongue in the form of decrease in the height of the filiform papillae with blunt ends, marked atrophy in some papillae with areas of focal loss, loss of some epithelial cells, pyknotic nuclei and cytoplasmic vacuoles in some epithelial cells. The lamina propria showed inflammatory cellular infiltration with congested blood vessels. Statistically, there were highly significant decrease in the number of proliferating cell nuclear antigen immunopositive cells, area percentage of Bcl-2 immunoexpression and highly significant increase in the collagen content compared to control group. Administration of RUT with ALS minimizes these changes. RUT protected the rat tongue against the histological and immunohistochemical changes induced by ALS through its antioxidant and anti-inflammatory properties.

New Delay Dependent Robust Stability Criteria for T–S Fuzzy Systems with Constant Delay

Said Idrissi,El Houssaine Tissir,Ismail Boumhidi,Noreddine Chaibi 제어·로봇·시스템학회 2013 International Journal of Control, Automation, and Vol.11 No.5

This paper deals with the problem of delay dependent robust stability for T–S fuzzy time delay systems. The approach based on constructing a new Lyapunov-Krasovskii functional by dividing uniformly the delay interval into N segment with N is positive integer, and using Finsler’s lemma. This new Lyapunov-Krasovskii functional is chosen with different weighted matrices corresponding to dif-ferent segments. The perturbations considered are norm bounded, and the results are expressed in terms of linear matrix inequality (LMIs). Numerical examples are provided to show the effectiveness of the present method, compared with some recent previous ones.

Foundations forlowcostbuildings

Sayed Abde lSalam,Mahmoud Samir El-kady 한국CDE학회 2017 Journal of computational design and engineering Vol.4 No.2

Attaining aneconomicalandsafedesignofstructuresisregardedasaprerequisiteforthestructuralengineer.Themarketpricesofreinforcingsteels havedramaticallysoaredinrecentyearsinternationally.Therefore,thepurposeofthecurrentpaperisnotjustreducingtheratioofreinforcing steelinthefoundationsforskeletonstructures,butratherminimizingthisratiothroughchoosingthemosteffectivefootingshape(folded stripfootings).Foldedfootingshavebeenusedasanalternativetotheconventionalrectangularstripfootings.Theheightofthestudiedmodel isten floors. Twodifferentfoundationsystemsareusedintheanalysisnamely;rectangularstripfootings,andfoldedstripfootingsrespectively. Bothfootingshapeswillbedesignedascontinuousfootingswithgridshapeunderthebuilding.Comparisonbetweenthetwosystems isalsopresentedregardingtheconcretesectionsandreinforcementratiounderthesameappliedloads.The finite elementanalysissoftware ADINAisusedinmodelingandanalysisofthestructuralandgeotechnicalbehaviorofbothtypesoffootings,withemphasisontheeffect ofchangingthefootingshapeonthestressesinthefootingconcretebodyandtheunderlyingsoils.Researchresultspresentstheinternalstresses withinthefootingandsoildomains,aswellasthecontactpressuredistributionforareinforcedfoldedstripfootingrestingondifferentsoil types.Theinfluence offoldinginclinationangle,andsoiltypeontheresultsarealsostudied.Resultsshowedthatfoldedstripfootingsareefficient inreducingtheamountofneededreinforcements,andsuchefficiency inreducingtherequiredsteelreinforcementinthefootingsisdepending ontheappliedfootingloads,andtosomedegreeonthesoiltypeandproperties.Reductioninthereinforcementratiobetweentherectangular andfoldedfootingtypesisabout26%infavorofthefoldedstripfootings.Acomparativeeconomicalstudyshowsthatthetotalcostof thereinforcedconcretesectionforthefoldedstripfootingsislessthanthetraditionalonebyabout18%.Thisdifferenceincostofbothtypesof footingsismainlyduetotherelativelysmallerinsteelreinforcementrationeededforthefoldedtypeascomparedwiththerectangularones. So, thefoldedstripfootingismoreeconomicalthantherectangularstripfooting.

FRACTIONAL DIFFERENTIAL EQUATIONS

El-Sayed, A.M.A.. Department of Mathematics 1988 Kyungpook mathematical journal Vol.28 No.2

In recent years, several authors have dealt with the fraction derivative [1], in special functions [2], convolution integral equation [5], differintegral equation [4], the derivative of H-function [6], and some other applications. The present paper considers the fraction derivatve in the form of differential eqiation.

Experimental Verification of Resistance-Demand Approach for Shear of HSC Beams

El-Sayed, Ahmed K.,Shuraim, Ahmed B. Korea Concrete Institute 2016 International Journal of Concrete Structures and M Vol.10 No.4

The resistance-demand approach has emerged as an effective approach for determining the shear capacity of reinforced concrete beams. This approach is based on the fact that both the shear resistance and shear demand are correlated with flexural tensile strain from compatibility and equilibrium requirements. The basic shear strength, under a given loading is determined from the intersection of the demand and resistance curves. This paper verifies the applicability of resistance-demand procedure for predicting the shear capacity of high strength concrete beams without web reinforcement. A total of 18 beams were constructed and tested in four-point bending up to failure. The test variables included the longitudinal reinforcement ratio, the shear span to depth ratio, and the beam depth. The shear capacity of the beams was predicted using the proposed procedure and compared with the experimental values. The results of the comparison showed good prediction capability and can be useful to design practice.

In-vitro release and in-vivo performance of tolmetin from different topical gel formulations

Sayed Hassan Auda,Saleh Abd El-Rasoul,Mahmoud Mohamed Ahmed,Shaaban Khalaf Osman,Mahmoud El-Badry 한국약제학회 2015 Journal of Pharmaceutical Investigation Vol.45 No.3

This study was designed to evaluate the suitability of Pluronic F-127, different grades of Carbopol and cellulosic polymers as gel bases containing tolmetin, a nonsteroidal anti-inflammatory drug. In vitro release characteristics, effect of enhancers, viscosity and the mechanism of drug release for different gel bases was studied as well as the anti-inflammatory activity were evaluated. The results showed that the HPMC gel has the superior percent of drug release than the others. The percent released of drug from Carbopol and the Pluronic F-127 gels is concentration defendants. It was found that the drug release from the tested gel bases obeyed the diffusion mechanism. The use of propylene glycol and urea in different concentrations (3.0, 5.0 and 10 % w/v) had enhanced the percent of drug release significantly (p<0.05). The anti-inflammatory activity of the drug in Carbopol gel formulation showed excellent anti-inflammatory activity. These finding highlight the potential local application of tolmetin gel as topical anti-inflammatory medication.

Status of Sperm Motiltity Treated with Endocrine Disruptors In Vitro

El-Sayed A. Mohamed,Sung-Jae Yoon,Woo-Sung Kwon,Yoo-Jin Park,Kyu-Hyun Jeong,Myung-Geol Pang 한국동물생명공학회(구 한국동물번식학회) 2011 발생공학 국제심포지엄 및 학술대회 Vol.2011 No.1

In the last few decades with the industrial revolution many environmental contaminants have estrogenic activity (endocrine disruptors, EDs) are released into the environment affecting the male reproductive system and male fertility. Sperm motility is one of the initial tests performed to assess sperm function; only motile sperm can achieve fertilization in vivo. The present study aimed to investigate the possible effects of a group of EDs that represent a widespread chemicals in the environment genistein (Gen), is a naturally occurring isoflavone (100 μM), bisphenol A (BPA), that is used in the manufacture of plastics and other products and released largely into the environment (100 μM), nonylphenol (NP) is an important environmental toxicant and potential endocrine disrupting chemical (10 μg/ml), TCDD, that is formed as an unwanted by-product in the manufacture of chlorinated hydrocarbons (2.5 μg/ml), atrazine (Atraz) is a herbicides (500 μM), dibromochloropropane (DBCP) is a pesticide (10 μg/ml), and diazinone (Diaz) is a insecticide (500 μM) on human sperm motility and kinematic characteristics. Human spermatozoa were incubated in Ham's F10 media with/without the tested chemicals or DMSO as positive control for 6 hr at 37℃ in 5% CO2. Then, sperm motility was assessed using computer assisted semen analyzer. Interestingly, all the chemicals tested significantly decreased sperm motility as compared to the control groups. However, only Diaz significantly decreased sperm kinematic characteristics namely, VCL, VSL, STR, VAP, and ALH. We suggest that the environmental chemicals may have an effect on male fertility via decreasing sperm motility.

A Trust Region Method for Solving the Decentralized Static Output Feedback Design Problem

El--Sayed M. E. Mostafa 한국전산응용수학회 2005 Journal of applied mathematics & informatics Vol.18 No.1-2

The decentralized static output feedback design problem is considered. A constrained trust region method is developed that solves this optimal control problem when a complete set of state variables is not available. The considered problem is interpreted as a non-linear (nonconvex) constrained matrix optimization problem. Then, a decentralized constrained trust region method is developed for this problem class exploiting the diagonal structure of the problem and using inexact computations.Finally, numerical results are given for the proposed method.