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Fracture Toughness of Glass-Carbon (0/90)_s Fiber Reinforced Polymer Composite – An Experimental and Numerical Study [PDF]
P.S. Shivakumar Gouda, S.K. Kudari, S. Prabhuswamy, Dayananda Jawali
Journal of Minerals and Materials Characterization and Engineering (JMMCE) , 2011, DOI: 10.4236/jmmce.2011.108052

Abstract: Mode-I fracture behavior of glass-carbon fiber reinforced hybrid polymer composite was investigated based on experimental and finite element analysis. The compact tension (CT) specimen was employed to conduct mode-I fracture test using special loading fixtures as per ASTM standards. Fracture toughness was determined experimentally for along and across the fiber orientation of the specimen. Results indicated that the cracked specimens are tougher along the fiber orientations as compared with across the fiber orientations. A similar fracture test was simulated using finite element analysis software ANSYS. Critical stress intensity factor (K) was calculated at fracture/failure using displacement extrapolation method, for both along and across the fiber orientations. The fractured surfaces of the glasscarbon epoxy composite under mode-I loading condition was examined by electron microscope.

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Improving the Dielectric Properties of High Density Polyethylene by Incorporating Clay-Nanofiller [PDF]
Ossama E. Gouda, Sohair F. Mahmoud, Ahmed A. El-Gendy, Ahmed S. Haiba
World Journal of Engineering and Technology (WJET) , 2014, DOI: 10.4236/wjet.2014.24030

Abstract: Polymer nanocomposites have been used for various important industrial applications. The preparation of high density polyethylene composed with Na-montmorillonite nanofiller using melt compounding method for different concentrations of clay-nanofiller of 0%, 2%, 6%, 10%, and 15% has been successfully done. The morphology of the obtained samples was optimized and characterized by scanning electron microscope showing the formation of the polymer nanocomposites. The thermal stability and dielectric properties were measured for the prepared samples. Thermal gravimetric analysis results show that thermal stability in polymer nanocomposites is more than that in the base polymer. It has been shown that the polymer nanocomposites exhibit some very different dielectric characteristics when compared to the base polymer. The dielectric breakdown strength is enhanced by the addition of clay-nanofiller. The dielectric constant (εr) and dissipation factor (Tan δ) have been studied in the frequency range 200 Hz to 2 MHz at room temperature indicating that enhancements have been occurred in εr and Tan δ by the addition of clay-nanofiller in the polymer material when compared with the pure material.

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Spectrophotometric determination of etodolac in pure form and pharmaceutical formulations
Ayman A Gouda, Wafaa S Hassan
Chemistry Central Journal , 2008, DOI: 10.1186/1752-153x-2-7

Abstract: We describe three simple, sensitive and reproducible spectrophotometric assays (A-C) for the determination of etodolac in pure form and in pharmaceutical formulations. Methods A and B are based on the oxidation of etodolac by Fe3+ in the presence of o-phenanthroline (o-phen) or bipyridyl (bipy). The formation of the tris-complex on reaction with Fe3+-o-phen and/or Fe3+-bipy mixtures in acetate buffer solution at optimum pH was demonstrated at 510 and 520 nm with o-phen and bipy. Method C is based on the oxidation of etodolac by Fe3+ in acidic medium, and the subsequent interaction of iron(II) with ferricyanide to form Prussian blue, with the product exhibiting an absorption maximum at 726 nm. The concentration ranges are 0.5–8, 1.0–10 and 2–18 μg mL-1 respectively for methods A, B and C. For more accurate analysis, Ringbom optimum concentration ranges were calculated, in addition to molar absorptivity, Sandell sensitivity, detection and quantification limits.Our methods were successfully applied to the determination of etodolac in bulk and pharmaceutical formulations without any interference from common excipients. The relative standard deviations were ≤ 0.76 %, with recoveries of 99.87 % – 100.21 %.Etodolac (ETD), 1,8-diethyl-1,3,4,9-tetrahydropyrano- [3,4-b]indole-1-acetic acid [1], is a non-steroidal anti-inflamatory antirheumatic drug (Scheme 1). A survey of the literature reveals that there are very few reported methods for the determination of ETD in biological fluids, pharmaceutical formulations and in presence of its enantiomer. Of those studies reported, the techniques used include chromatography, HPLC [2-5], GC [6-8], in addition to spectrofluorimetric [9] and spectrophotometric methods [9-11]. However, an extensive survey of the literature revealed that there is no method available for the simultaneous determination of ETD in pure form and pharmaceutical formulations by oxidation-reduction reactions.The aim of this study was to apply redox reactions in de

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MNCs and Community Relations: The Challenge of CSR in Developing Countries
Prof. S. L. Hiremath,Mr. Sateesh Gouda M
Indian Streams Research Journal , 2012,

Abstract: Corporate social responsibility (CSR) is a response of a re-thought role of businesses. This trend emerges in a field where globalization empowers stakeholders that increase surveillance over corporation's activities especially in developing countries. In this context, multinational companies (MNCs) have definitively recognized that a free rider? strategy for their activities on Developing countries is not a sustainable option for them and, that the actual field of global business exhorts companies to go further community relations through strategies that add significant value by real engage with communities.

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A morpho-etiological description of congenital limb anomalies.
Tayel S,Fawzia M,Al-Naqeeb Niran,Gouda Said
Annals of Saudi Medicine , 2005,

Abstract: Background: Limb anomalies rank behind congenital heart disease as the most common birth defects observed in infants. More than 50 classifications for limb anomalies based on morphology and osseous anatomy have been drafted over the past 150 years. The present work aims to provide a concise summary of the most common congenital limb anomalies on a morpho-etiological basis. Patients and Methods: In a retrospective study, 70 newborns with anomalies of the upper and/or lower limbs were ascertained through clinical examination, chromosomal analysis, skeletal surveys and other relevant investigations. Results: Fetal causes of limb anomalies represented 55.8% of the cases in the form of 9 cases (12.9%) with chromosomal aberrations (trisomy 13, 18 and 21, duplication 13q and deletion 22q) and 30 cases (42.9%) with single gene disorders. An environmental etiology for limb anomalies was diagnosed in 11 cases (15.7%) as amniotic band disruption, monozygotic twin with abnormal circulation, vascular disruption (Poland sequence, sirenomelia and general vascular disruption) and an infant with a diabetic mother. Twenty cases (28.5%) had limb anomalies as part of sporadic syndromes of unknown etiology. Conclusions: The morpho-etiological work-up of limb anomalies adopted in the present study is valuable for detecting the cause of the anomaly and is crucial for its prevention. Prevention can be achieved by proper genetic counseling, which includes recurrence risk estimation and prenatal diagnosis.

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Augmentation of Multifunctional Properties of Cellulosic Cotton Fabric Using Titanium Dioxide Nanoparticles [PDF]
Mohamed Gouda, Abdullah Ibrahim Aljaafari
Advances in Nanoparticles (ANP) , 2012, DOI: 10.4236/anp.2012.13005

Abstract: Titanium dioxide nanoparticle was synthesized by the reduction of titanium tetrachloride using borohydride, water as solvent, and polyvinyl-pyrrolidone as stabilizer. The average size of nano-TiO₂ is estimated to be 5 - 10 nm using a transmission electron microscope (TEM); this was confirmed by X-ray diffraction and UV-Vis spectroscopy. Nano-TiO₂ was impregnated into cotton fabric to impart multifunctional properties and this was confirmed by scanning electron microscope and scanning electron microscope coupled with high energy distribution X-Ray (SEM-EDX). The TiO₂ nanoparticles loaded cotton fabrics showed excellent antibacterial activity against two representative bacteria, Staphylococcus aureus (Gram positive) 96.6% and Klebsiella pneumonia (Gram negative) 95.2%. Also, TiO₂ nanoparticles enhanced the self-cleaning and the protection of cotton fabrics against UV radiation in comparison with the untreated cotton fabrics. The TiO₂ nanoparticles were durable in-situ cotton fabrics even after 20 laundering wash cycles.

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Visions of empire. Changing American perspectives on Dutch colonial rule in Indonesia between 1920 and 1942
F. Gouda
BMGN : Low Countries Historical Review , 1994,

Abstract:

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Analysis of Non-Linear Mode Coupling of Cosmological Density Fluctuations by the Pseudo-Spectral Method
Naoteru Gouda
Physics , 1995, DOI: 10.1143/PTP.94.33

Abstract: The pseudo-spectral method is proposed for following the evolution of density and velocity fluctuations at the weakly non-linear stage in the expanding universe with a good accuracy. In this method, the evolution of density and velocity fluctuations is integrated in the Fourier Space with using FFT. This method is very useful to investigate accurately the non-linear dynamics in the weakly non-linear regime. Because the pseudo-spectral method works directly in the Fourier space, it should be especially useful for examining behavior in the Fourier domain, for an example, the effects of the non-linear coupling of different wave modes on the evolution of the power spectrum. I show the results of this analysis both in one and three dimensional systems.

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The need for logbooks to evolve in the undergraduate medical setting
Pishoy Gouda
- , 2016, DOI: 10.1007/s40037-015-0249-x

Abstract: is a medical graduate from the National University of Ireland, Galway. He is the past chairperson of Association of Medical Students in Ireland. He is currently enrolled in MSc of Clinical Trials at the London School of Tropical Hygiene and Medicine and working as a research assistant at the University of Alberta, Division of Cardiology

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