Search results for: G. Patricia Abdel Rahim
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 520

Search results for: G. Patricia Abdel Rahim

520 Calculated Structural and Electronic Properties of Mg and Bi

Authors: G. Patricia Abdel Rahim, Jairo Arbey Rodriguez M, María Guadalupe Moreno Armenta

Abstract:

The present study shows the structural, electronic and magnetic properties of magnesium (Mg) and bismuth (Bi) in a supercell (1X1X5). For both materials were studied in five crystalline structures: rock salt (NaCl), cesium chloride (CsCl), zinc-blende (ZB), wurtzite (WZ), and nickel arsenide (NiAs), using the Density Functional Theory (DFT), the Generalized Gradient Approximation (GGA), and the Full Potential Linear Augmented Plane Wave (FP-LAPW) method. By means of fitting the Murnaghan's state equation we determine the lattice constant, the bulk modulus and it's derived with the pressure. Also we calculated the density of states (DOS) and the band structure.

Keywords: bismuth, magnesium, pseudo-potential, supercell

Procedia PDF Downloads 822
519 First-Principles Investigation of the Structural and Electronic Properties of Mg1-xBixO

Authors: G. P. Abdel Rahim, M. María Guadalupe Moreno Armenta, Jairo Arbey Rodriguez

Abstract:

We investigated the structure and electronic properties of the compound Mg1-xBixO with varying concentrations of 0, ¼, ½, and ¾ x bismuth in the the NaCl (rock-salt) and WZ (wurtzite) phases. The calculations were performed using the first-principles pseudo-potential method within the framework of spin density functional theory (DFT). Our calculations predict that for Bi concentrations greater than ~70%, the WZ structure is more favorable than the NaCl one and that for x = 0 (pure MgO), x = 0.25 and x = 0.50 of Bi concentration the NaCl structure is more favorable than the WZ one. For x = 0.75 of Bi, a transition from wurtzite towards NaCl is possible, when the pressure is about 22 GPa. Also It has been observed the crystal lattice constant closely follows Vegard’s law, that the bulk modulus and the cohesion energy decrease with the concentration x of Bi.

Keywords: DFT, Mg1-xBixO, pseudo-potential, rock-salt, wurtzite

Procedia PDF Downloads 525
518 Blood Glucose Measurement and Analysis: Methodology

Authors: I. M. Abd Rahim, H. Abdul Rahim, R. Ghazali

Abstract:

There is numerous non-invasive blood glucose measurement technique developed by researchers, and near infrared (NIR) is the potential technique nowadays. However, there are some disagreements on the optimal wavelength range that is suitable to be used as the reference of the glucose substance in the blood. This paper focuses on the experimental data collection technique and also the analysis method used to analyze the data gained from the experiment. The selection of suitable linear and non-linear model structure is essential in prediction system, as the system developed need to be conceivably accurate.

Keywords: linear, near-infrared (NIR), non-invasive, non-linear, prediction system

Procedia PDF Downloads 459
517 Thermal Transformation and Structural on Se90Te7Cu3 Chalcogenide Glass

Authors: Farid M. Abdel-Rahim

Abstract:

In this study, Se90Te7Cu3 chalcogenide glass was prepared using the melt quenching technique. The amorphous nature of the as prepared samples was confirmed by scanning electron microscope (SEM). Result of differential scanning calorimetric (DSC) under nonisothermal condition on composition bulk materials are reported and discussed. It shows that these glasses exhibit a single-stage glass transition and a single-stage crystallization on heating rates. The glass transition temperature (Tg), the onset crystallization (Tc), the crystallization temperature (Tp), were found by dependent on the composition and heating rates. Activation energy for glass transition (Et), activation energy of the amorphous –crystalline transformation (Ec), crystallization reaction rate constant (Kp), (n) and (m) are constants related to crystallization mechanism of the bulk samples have been determined by different formulations.

Keywords: chalcogenides, heat treatment, DSC, SEM, glass transition, thermal analysis

Procedia PDF Downloads 397
516 Line Manager’s Role Involvement towards Creating a Coaching Culture in Nursing Area

Authors: N. S. A. Rahim, N. N. Abu Mansor, M. I. Saidi, N. R. A. Rahim, K. F. Adrutdin

Abstract:

The use of coaching as one of organizational culture with the contribution of the involvement of line manager roles is an important to update employees’ knowledge and skills continuously. In healthcare sector, it is dynamic that nurse must update their knowledge and skills to keep pace with change. This paper attempts to discuss the involvement of line manager roles towards creating a coaching culture who give their support and innovation towards motivate nurses to give their best performance either in public or private hospitals.

Keywords: nursing, line managers’ roles, coaching, coaching culture

Procedia PDF Downloads 448
515 Finite Element Method for Solving the Generalized RLW Equation

Authors: Abdel-Maksoud Abdel-Kader Soliman

Abstract:

The General Regularized Long Wave (GRLW) equation is solved numerically by giving a new algorithm based on collocation method using quartic B-splines at the mid-knot points as element shape. Also, we use the Fourth Runge-Kutta method for solving the system of first order ordinary differential equations instead of finite difference method. Our test problems, including the migration and interaction of solitary waves, are used to validate the algorithm which is found to be accurate and efficient. The three invariants of the motion are evaluated to determine the conservation properties of the algorithm.

Keywords: generalized RLW equation, solitons, quartic b-spline, nonlinear partial differential equations, difference equations

Procedia PDF Downloads 489
514 Non-Destructive Testing of Metal Pipes with Ultrasonic Sensors Based on Determination of Maximum Ultrasonic Frequency

Authors: Herlina Abdul Rahim, Javad Abbaszadeh, Ruzairi Abdul Rahim

Abstract:

In this research, the non-invasive ultrasonic transmission tomography is investigated. In order to model the ultrasonic wave scattering for different thickness of metal pipes, two-dimensional (2D) finite element modeling (FEM) has been utilized. The wall thickness variation of the metal pipe and its influence on propagation of the ultrasonic pressure wave are explored in this paper, includes frequency analysing in order to find the maximum applicable frequency. The simulation results have been compared to experimental data and are shown to provide key insight for this well-defined experimental case by explaining the achieved reconstructed images from experimental setup. Finally, the experimental results which are useful for further investigation for the application of ultrasonic transmission tomography in industry are illustrated.

Keywords: ultrasonic transmission tomography, ultrasonic sensors, ultrasonic wave, non-invasive tomography, metal pipe

Procedia PDF Downloads 358
513 Chemical Analysis, Antioxidant Activity and Antimicrobial Activity of Isolated Compounds and Essential Oil from Callistemon citrinus Leaf

Authors: Manal M. Hamed, Mosad A. Ghareeb, Abdel-Aleem H. Abdel-Aleem, Amal M. Saad, Mohamed S. Abdel-Aziz, Asmaa H. Hadad

Abstract:

Natural products derived from medicinal plants provide unlimited opportunities for a new medication leads because of the unmatched accessibility of chemical variation. Six compounds were isolated from the n-butanol extract of Callistemon citrinus (Family Myrtaceae), they were identified as; nepetolide (1), callislignan A (2), 6,8-dimethoxy-4,5-dimethyl-3-methyleneisochroman-1-one (3), 3-methyl-7-O-benzoyl-β-D-glucopyranoside (4), 5, 7, 3', 5'-tetrahydroxy-6, 8-di-C-methyl flavanone (5), and (2R,3R,4S,5S)-2,4-bis(4-hydroxyphenyl)-3,5-dihydroxy-tetrahydropyran (6). The isolated compounds were evaluated as antioxidant and antimicrobial agents. The antioxidant activities of the compounds were determined using DPPH-radical scavenging and total antioxidant capacity (TAC) assays. The results indicated that compound (5) was most active in its capacity to scavenge free radicals in the DPPH assay [SC50 value, 4.65 ± 0.74μg/mL] compared to the standard ascorbic acid and exhibited the highest activity in the TAC assay (610.45 ± 1.67mg AAE/g compound). The pure isolates were tested for their antimicrobial activity against four pathogenic microbial strains including Staphylococcus aureus, Methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa and Candida albicans. Also, the GC/MS analysis of its leaves essential oil presented nine identified compounds representing 91% of the total oil constituents. The outcomes got from this study give a reasonable justification for the medicinal uses of Callistemon citrinus plant.

Keywords: Callistemon citrinus, flavanone, antioxidant activity, antimicrobial activity, essential oil, Myrtaceae

Procedia PDF Downloads 295
512 History on the Screen: Nasser and the Biographical Film in Egyptian Cinema

Authors: Omar Khalifah

Abstract:

The emergence of Muhammad Fadel’s 1996 film ‘Nasser 56’ ushered in a new era in Egyptian cinema. Not only was it the first biographical film of late Egyptian president Gamal ‘Abdel Nasser (1918-1970); it also broke a long-accepted taboo against cinematic depiction of modern political leaders. Passionately received by Egyptians and Arabs throughout the world, the success of ‘Nasser 56’ empowered other filmmakers to follow Fadel’s suit. Interestingly, the three biographical films that followed had, completely or partially, a Nasser dimension. In addition to another biographical film of Nasser, Anwar al-Qawadri’s ‘Gamal ‘Abdel Nasser’ (1999); Muhammad Khan’s ‘Ayyam al-Sadat (Days of Sadat)’ (2001), and Sherif Arafa’s ‘Halim (Halim)’ (2006) portray, as the titles clearly suggest, two significant figures whose lives thoroughly intersected with Nasser’s - Nasser’s successor Anwar al-Sadat and the legendary singer Abdel Halim Hafiz. Expectedly, therefore, Nasser himself is abundantly referenced in those films, albeit differently. This paper seeks to examine the ways in which Egyptian filmmakers impersonate Nasser on the screen. Starting with scholarly definitions of the biopic, the paper will first ponder the reasons that have made the biopic an unattractive genre to Egyptian filmmakers. It will then argue that the popularity of Nasser and his wide appeal to the public has transformed the status of the biopic genre in Egyptian cinema. However, the impersonation of Nasser in the four films above proved a daunting mission to filmmakers. As this paper will show, unless he is the main character, the reenactment of Nasser in films will constantly pose dilemmas to filmmakers, a few of which will be discussed in this paper.

Keywords: Ahmad Zaki, bio-pictures, Egyptian cinema, Nasser, Nasser 56

Procedia PDF Downloads 419
511 Study the Effect of Dermal Application of Stone Hair Dye on Experimental Animals

Authors: Hatem Abdel Moniem Ahmed, Ragaa Mohamed Abdel Maaboud, Heba A. Mubarak

Abstract:

A commercially available Stone Hair Dye (SHD) was spread in Upper Egypt and used for dying woman's hair. Paraphenyl-diamine (PPD) is the main component of SHD and reported as a toxic substance. This work aims to study the systemic effects induced in experimental animals as a result of dermal application of SHD. 21 rats were divided into three groups, and doses of SHD and PPD were applied according to body weight (25 mg/100 g body weight) for 90 days. The results revealed that insignificant decrease in RBC count and Hb level, but there were significant increases in the WBC count, AST, ALT, GPT, and total protein while creatinine level was insignificantly increased. Hepatocytes showed a lot of degenerative changes in the form of vacuolated cytoplasm and irregular deeply stained nuclei with vascular congestion and lymphocytic infiltration, while renal affection indicated the occurrence of atrophy of glomerular capillaries, hyperplasia, and widening of bowman space.

Keywords: PPD, SHD, rats and histology, biochemistry and hematology

Procedia PDF Downloads 451
510 Harnessing the Generation of Ferromagnetic and Silver Nanostructures from Tropical Aquatic Microbial Nanofactories

Authors: Patricia Jayshree Jacob, Mas Jaffri Masarudinb, Mohd Zobir Hussein, Raha Abdul Rahim

Abstract:

Iron based ferromagnetic nanoparticles (IONP) and silver nanostructures (AgNP) have found a wide range of application in antimicrobial therapy, cell targeting, and environmental applications. As such, the design of well-defined monodisperse IONPs and AgNPs have become an essential tool in nanotechnology. Fabrication of these nanostructures using conventional methods is not environmentally conducive and weigh heavily on energy and outlays. Selected microorganisms possess the innate ability to reduce metallic ions in colloidal aqueous solution to generate nanoparticles. Hence, harnessing this potential is a way forward in constructing microbial nano-factories, capable of churning out high yields of well-defined IONP’s and AgNP's with physicochemical characteristics on par with the best synthetically produced nanostructures. In this paper, we report the isolation and characterization of bacterial strains isolated from the tropical marine and freshwater ecosystems of Malaysia that demonstrated facile and rapid generation of ferromagnetic nanoparticles and silver nanostructures when precursors such as FeCl₃.6H₂O and AgNO₃ were added to the cell-free bacterial lysate in colloidal solution. Characterization of these nanoparticles was carried out using FESEM, UV Spectrophotometer, XRD, DLS and FTIR. This aerobic bioprocess was carried out at ambient temperature and humidity and has the potential to be developed for environmental friendly, cost effective large scale production of IONP’s. A preliminary bioprocess study on the harvesting time, incubation temperature and pH was also carried out to determine pertinent abiotic parameters contributing to the optimal production of these nanostructures.

Keywords: iron oxide nanoparticles, silver nanoparticles, biosynthesis, aquatic bacteria

Procedia PDF Downloads 285
509 Reliability of Slender Reinforced Concrete Columns: Part 1

Authors: Metwally Abdel Aziz Ahmed, Ahmed Shaban Abdel Hay Gabr, Inas Mohamed Saleh

Abstract:

The main objective of structural design is to ensure safety and functional performance requirements of a structural system for its target reliability levels. In this study, the reliability index for the reinforcement concrete slender columns with rectangular cross section is studied. The variable parameters studied include the loads, the concrete compressive strength, the steel yield strength, the dimensions of concrete cross-section, the reinforcement ratio, and the location of steel placement. Risk analysis program was used to perform the analytical study. The effect of load eccentricity on the reliability index of reinforced concrete slender column was studied and presented. The results of this study indicate that the good quality control improve the performance of slender reinforced columns through increasing the reliability index β.

Keywords: reliability, reinforced concrete, safety, slender column

Procedia PDF Downloads 453
508 Kinematic Behavior of Geogrid Reinforcements during Earthquakes

Authors: Ahmed Hosny Abdel-Rahman, Mohamed Abdel-Moneim

Abstract:

Reinforced earth structures are generally subjected to cyclic loading generated from earthquakes. This paper presents a summary of the results and analyses of a testing program carried out in a large-scale multi-function geosynthetic testing apparatus that accommodates soil samples up to 1.0 m3. This apparatus performs different shear and pullout tests under both static and cyclic loading. The testing program was carried out to investigate the controlling factors affecting soil/geogrid interaction under cyclic loading. The extensibility of the geogrids, the applied normal stresses, the characteristics of the cyclic loading (frequency, and amplitude), and initial static load within the geogrid sheet were considered in the testing program. Based on the findings of the testing program, the effect of these parameters on the pullout resistance of geogrids, as well as the displacement mobility under cyclic loading were evaluated. Conclusions and recommendations for the design of reinforced earth walls under cyclic loading are presented.

Keywords: geogrid, soil, interface, cyclic loading, pullout, large scale testing

Procedia PDF Downloads 622
507 Dye Removal from Aqueous Solution by Regenerated Spent Bleaching Earth

Authors: Ahmed I. Shehab, Sabah M. Abdel Basir, M. A. Abdel Khalek, M. H. Soliman, G. Elgemeie

Abstract:

Spent bleaching earth (SBE) recycling and utilization as an adsorbent to eliminate dyes from aqueous solution was studied. Organic solvents and subsequent thermal treatment were carried out to recover and reactivate the SBE. The effect of pH, temperature, dye’s initial concentration, and contact time on the dye removal using recycled spent bleaching earth (RSBE) was investigated. Recycled SBE showed better removal affinity of cationic than anionic dyes. The maximum removal was achieved at pH 2 and 8 for anionic and cationic dyes, respectively. Kinetic data matched with the pseudo second-order model. The adsorption phenomenon governing this process was identified by the Langmuir and Freundlich isotherms for anionic dye while Freundlich model represented the sorption process for cationic dye. The changes of Gibbs free energy (ΔG°), enthalpy (ΔH°), and entropy (ΔS°) were computed and compared through thermodynamic study for both dyes.

Keywords: Spent bleaching earth, reactivation, regeneration, thermal treatment, dye removal, thermodynamic

Procedia PDF Downloads 183
506 Enhancing Educational Environments: Maximizing School Playground Potential Through Biophilic Design

Authors: Esraa Abdel-Salam, Tarek Farghaly, Hassan Abdel-Salam, Asmaa Hasan

Abstract:

Increasing evidence indicates that the growing disconnect between humans and the natural environment, propelled by technological advancements, has had adverse impacts on human health and overall well-being. Therefore, bridging the gap between humans and nature, the biophilia hypothesis emerges as a relatively theoretical and less comprehensively studied concept, though it has great potential for alternative design ideas. The research aims to enhance school playgrounds with biophilic design, positively impacting children's mental and physical well-being. This paper investigates the integration of biophilic design in school playgrounds and its influence on the well-being of children. It involves an analysis of three playgrounds in Alexandria, Egypt, each exhibiting varying degrees of biophilic design principles. The study investigates how these design elements enhance students' experiences by improving their surrounding environments. The research aims to develop a design framework and recommendations for creating or modifying playgrounds to enhance the physical and mental well-being of children.

Keywords: biophilic design, physical health, mental well-being, children’s development, school playground

Procedia PDF Downloads 23
505 Linear Prediction System in Measuring Glucose Level in Blood

Authors: Intan Maisarah Abd Rahim, Herlina Abdul Rahim, Rashidah Ghazali

Abstract:

Diabetes is a medical condition that can lead to various diseases such as stroke, heart disease, blindness and obesity. In clinical practice, the concern of the diabetic patients towards the blood glucose examination is rather alarming as some of the individual describing it as something painful with pinprick and pinch. As for some patient with high level of glucose level, pricking the fingers multiple times a day with the conventional glucose meter for close monitoring can be tiresome, time consuming and painful. With these concerns, several non-invasive techniques were used by researchers in measuring the glucose level in blood, including ultrasonic sensor implementation, multisensory systems, absorbance of transmittance, bio-impedance, voltage intensity, and thermography. This paper is discussing the application of the near-infrared (NIR) spectroscopy as a non-invasive method in measuring the glucose level and the implementation of the linear system identification model in predicting the output data for the NIR measurement. In this study, the wavelengths considered are at the 1450 nm and 1950 nm. Both of these wavelengths showed the most reliable information on the glucose presence in blood. Then, the linear Autoregressive Moving Average Exogenous model (ARMAX) model with both un-regularized and regularized methods was implemented in predicting the output result for the NIR measurement in order to investigate the practicality of the linear system in this study. However, the result showed only 50.11% accuracy obtained from the system which is far from the satisfying results that should be obtained.

Keywords: diabetes, glucose level, linear, near-infrared, non-invasive, prediction system

Procedia PDF Downloads 159
504 ICT Training Programs in Tourism and Hospitality Institutes: An Analytical Study of Types, Effectiveness, and Graduate Perceived Importance

Authors: Magdy Abdel-Aleem Abdel-Ati Mayouf, Islam Al Sayed Hussein Al Sayed

Abstract:

Development of tourism and hospitality faculties' graduates is a key to the future health of hospitality and tourism sectors. Meanwhile information and communication technologies (ICTs) increasingly become the driving engine for productivity improvement and business opportunities in tourism and hospitality industry. Tourism and hospitality education and training must address these developments to enhance the ability of future managers to adopt a variety of ICT tools and strategies to increase their organization's efficiency and competitiveness. Therefore, this study aims to explore the types and effectiveness of ICT training offered by faculties of tourism and hotels in Egypt, and evaluating the importance of that training from the graduate's point of view. The study targets the graduates who graduated in the present ten years from three different faculties of tourism and hotels. Results argued the types, levels and effectiveness of ICT training offered in these faculties and the extent to which training programs were appreciated by graduates working in different fields, and finally, it recommended particular practices to enhance the training efficiency and raising the perceived benefits of it for workers in tourism and hospitality fields.

Keywords: training, IT, graduated, tourism and hospitality, education

Procedia PDF Downloads 362
503 In vitro Susceptibility of Madurella mycetomatis to the Extracts of Anogeissus leiocarpus Leaves

Authors: Ikram Mohamed Eltayeb Elsiddig, Abdel Khalig Muddather, Hiba Abdel Rahman Ali, Saad Mohamed Hussein Ayoub

Abstract:

Anogeissusleiocarpus (Combretaceae) is well known for its medicinal uses in African traditional medicine, for treating many human diseases mainly skin diseases and infections.Mycetoma disease is a fungal and/ or bacterial skin infection, mainly cause by Madurella mycetomatis fungus.This study was carried out in vitro to investigate the antifungal activity of Anogeissusleiocarpus leaf extracts against the isolated pathogenicMadurellamycetomatis, by using the NCCLS modified method compared to Ketoconazole standard drug and MTT assay. The bioactive fraction was subjected to chemical analysis implementing different chromatographic analytical methods (TLC, HPLC, and LC-MS/MS). The results showed significance antifungal activity of A. leiocarpus leaf extractsagainst the isolated pathogenicM. mycetomatis, compared to negative and positive controls. The chloroform fraction showed the highest antifungal activity.The chromatographic analysis of the chloroform fraction with the highest activity showed the presence of important bioactive compounds such as ellagic and flavellagic acids derivatives, flavonoids and stilbenoid, which are well known for their antifungal activity.

Keywords: Anogeissus leiocarpus, crude extracts and fractions of Anogeissus leiocarpus, in vitrosusceptibility of Madurella mycetomatis, Madurella mycetomatis

Procedia PDF Downloads 622
502 Cultural Factors Associated with Male Criminal Behavior and Inmate Population

Authors: Patricia Martinez Lanz, Patricia Hernandez Valdez

Abstract:

Over the last decade, crime has reached unprecedented levels and has caused much violent death in Mexico. To establish factors that potentially can facilitate crime, as well as the status of the emotional wellbeing presented in prison population, the present study was realized with a sample composed of 299 inmates of the Federal Center for Social Reinsertion in Oaxaca, Mexico. A questionnaire was specifically developed designed and applied to this population, evaluating sociodemographic factors and four Likert scales: substance consumption (drugs and alcohol), domestic violence and depressive symptoms. Reliability was adequate (Cronbach's Alpha= .703) and validity of the instrument showed appropriate relations between the reagents of each scale. Results showed through Chi Square analysis, statistically significant differences in the correlations between sociodemographic factors, domestic violence, addictions and depressive symptoms. Results reported that most of the inmates were between 28 and 47 years old (51.8%), had a low educational level (elementary school 42.5%), were in consensual union (42.5%), had high and severe levels of alcohol consumption (43.5% of the cases) and reported the presence of high and severe level of depression (28.9% of the cases). The results of this research are part of a national study of all Federal Centers for Social Reinsertion System in Mexico, in order to developed intervention strategies used in prison to prevent crime.

Keywords: delinquency, addictions, violence, depression, crime, criminal behavior

Procedia PDF Downloads 174
501 Strengthening Reinforced Concrete Beams Using Carbon Fibre Reinforced Polymer Strips

Authors: Mina Iskander, Mina Melad, Mourad Yasser, Waleed Abdel Rahim, Amr Mosa, Mohamed El Lahamy, Ezzeldin Sayed-Ahmed, Mohamed Abou-Zeid

Abstract:

Strengthening of reinforced concrete beams in flexure using externally bonded composite laminate of high tensile strength is easy and of the minimum cost compared to traditional methods such as increasing the concrete section depth or reinforcement that requires formwork and curing which affect the structure usability. One of the main limitations of this technique is debonding of the externally bonded laminate, either by end delamination or by mid-span flexural crack-induced debonding. ACI 440.2-08 suggests that using side-bonded FRP laminate in the flexural strengthening of RC beams may serve to limit the extent and width of flexural cracks. Consequently, this technique may decrease the effect of flexural cracks on initiating the mid-span debonding; i.e. delays the flexural crack-induced debonding. Furthermore, bonding the FRP strips to the side of the beam may offer an attractive, practical solution when the soffit of this beam is not accessible. This paper presents an experimental programme designed to investigate the effect of using externally bonded CFRP laminate on the sides of reinforced concrete beams and compares the results to those of bonding the CFRP laminate to the soffit of the beams. In addition, the paper discusses the effect of using end anchorage by U-wrapping the CFRP strips at their end zones with CFRP sheets for beams strengthened with soffit-bonded and side-bonded CFRP strips. Thus, ten rectangular reinforced concrete beams were tested to failure in order to study the effect of changing the location of the externally bonded laminate on the flexural capacity and ductility of the strengthened beams. Pultruded CFRP strips were bonded to the soffit of the beams or their sides to check the possibility of limiting the flexural cracking in mid-span region, which is the main reason for mid-span debonding. Pre-peg CFRP sheets were used near the support as U-wrap for the beam to act as an end-anchorage for the externally bonded strips in order to delay/prevent the end delamination. Strength gains of 38% and 43% were recorded for the soffit-bonded and the side-bonded composite strips with end U-wrapped sheets, respectively. Furthermore, beams with end sheets applied as an end anchorage showed higher ductility than those without these sheets.

Keywords: flexural strengthening, externally bonded CFRP, side-bonded CFRP, CFRP laminates

Procedia PDF Downloads 355
500 CFD Modeling of Boiling in a Microchannel Based On Phase-Field Method

Authors: Rahim Jafari, Tuba Okutucu-Özyurt

Abstract:

The hydrodynamics and heat transfer characteristics of a vaporized elongated bubble in a rectangular microchannel have been simulated based on Cahn-Hilliard phase-field method. In the simulations, the initially nucleated bubble starts growing as it comes in contact with superheated water. The growing shape of the bubble compared with the available experimental data in the literature.

Keywords: microchannel, boiling, Cahn-Hilliard method, simulation

Procedia PDF Downloads 423
499 Developing Mathematical Relationships to Evaluate the Amount of Added Ease to the Basic Pattern of Weft Knitting Fabrics and Its Fitting to the Upper Part of Egyptian Women's Bodies

Authors: Hebatullah Ali Abdel-Aleem Abdel-Hamid, Camellia Mousa Mohamed Elzean

Abstract:

Knitted garments recently became a key component in wardrobes of the Egyptian woman. Many Egyptian women depend on garments made of knitted fabrics in their outer appearance because of its specific properties including flexibility. Through observation and application, it was noticed that knitwear blocks that used for knitted fabrics somehow does not fit the figures of the Egyptian women. Moreover, the pattern makers are usually confused and unable to choose the suitable blocks for different knitting fabrics taking into consideration its physical and mechanical properties. This study seeks to develop mathematical relationships for evaluation of the amount of added- or subtracted ease to Aldrich’s basic fitting blocks for some weft knitting fabrics and its fitting to the upper part of Egyptian women's bodies. To achieve this goal, 12 samples were used to evaluate fitting of Aldrich’s Basic Fitting Block to the upper part of Egyptian women's bodies. The samples were evaluated before and after alterations, through wear trials on the standard mannequins of size 48 and 56, and judged by experienced assessors using fit evaluation scale. The data obtained were statistically analyzed to identify the efficiency of the adjustments. The Aldrich’s Basic Fitting Block was selected because his method is known internationally and easy to use.

Keywords: Aldrich basic fitting block, clothing industry, knitted fabrics, pattern construction

Procedia PDF Downloads 266
498 Factors Controlling Durability of Some Egyptian Non-Stylolitic Marbleized Limestone to Salt Weathering

Authors: H. El Shayab, G. M. Kamh, N. G. Abdel Ghafour, M. L. Abdel Latif

Abstract:

Nowadays, marbleized limestone becomes one of the most important sources of the mineral wealth in Egypt as they have beautiful colors (white, grey, rose, yellow and creamy, etc.) make it very suitable for decoration purposes. Non-styolitic marbleized limestone which not contains styolitic surfaces. The current study aims to study different factors controlling durability of non-styolitic marbleized limestone against salt crystallization weathering. The achievement aim of the research was required nine representative samples were collected from the studied areas. Three samples from each of the studied areas. The studied samples was characterized by various instrumental methods before salt weathering, to determine its mineralogical composition, chemical composition and pore physical properties respectively. The obtained results revealed that both of Duwi and Delga studied samples nearly have the same average ∆M% 1.63 and 1.51 respectively and consequently A.I. stage of deformation. On the other hand, average ∆M% of Wata studied samples is 0.29 i.e. lower than two other studied areas. Wata studied samples are more durable against salt crystallization test than Duwi and Delga. The difference in salt crystallization durability may be resulted from one of the following factors: Microscopic textural effect as both of micrite and skeletal percent are in directly proportional to durability of stones to salt weathering. Dolomite mineral present as a secondary are in indirectly proportional to durability of stones to salt weathering. Increase in MgO% also associated with decrease the durability of studied samples against salt crystallization test. Finally, all factors affecting positively against salt crystallization test presents in Wadi Wata studied samples rather than others two areas.

Keywords: marbleized limestone, salt weathering, Wata, salt weathering

Procedia PDF Downloads 327
497 Indoleamine 2,3 Dioxygenase and Regulatory T Cells in Acute Myeloid Leukemia

Authors: Iman M. Mansour, Rania A. Zayed, Fadwa S. Abdel-Azim, Lamyaa H. Abdel-Latif

Abstract:

Background and Objectives: The microenvironment of acute myeloid leukemia (AML) is suppressive for immune cells. Regulatory T cells (Tregs) have been recognized to play a role in helping leukemic cells to evade immunesurveillance. The mesenchymal stem cells (MSCs) are essential contributors in immunomodulation of the microenvironment as they can promote differentiation of Tregs via the indoleamine 2,3-dioxygenase (IDO) pathway. The aim of the present work was to evaluate the expression of IDO in bone marrow derived MSCs and to study its correlation to percentage of Tregs. Methods: 37 adult bone marrow samples were cultured in appropriate culture medium to isolate MSCs. Successful harvest of MSCs was determined by plastic adherence, morphology and positive expression of CD271 and CD105; negative expression of CD34 and CD45 using flowcytometry. MSCs were examined for IDO expression by immunocytochemistry using anti-IDO monoclonal antibody. CD4+ CD25+ cells (Tregs) were measured in bone marrow samples by flowcytometry. Results: MSCs were successfully isolated from 20 of the 37 bone marrow samples cultured. MSCs showed higher expression of IDO and Tregs percentage was higher in AML patients compared to control subjects (p=0.002 and p<0.001 respectively). A positive correlation was found between IDO expression and Tregs percentage (p value=0.012, r=0.5). Conclusion: In this study, we revealed an association between high IDO expression in MSCs and elevated levels of Tregs which has an important role in the pathogenesis of AML, providing immunosuppressive microenvironment.

Keywords: acute myeloid leukemia, indoleamine 2, 3-dioxygenase, mesenchymal stem cells, T regulatory cells

Procedia PDF Downloads 359
496 Fabrication of Cheap Novel 3d Porous Scaffolds Activated by Nano-Particles and Active Molecules for Bone Regeneration and Drug Delivery Applications

Authors: Mostafa Mabrouk, Basma E. Abdel-Ghany, Mona Moaness, Bothaina M. Abdel-Hady, Hanan H. Beherei

Abstract:

Tissue engineering became a promising field for bone repair and regenerative medicine in which cultured cells, scaffolds and osteogenic inductive signals are used to regenerate tissues. The annual cost of treating bone defects in Egypt has been estimated to be many billions, while enormous costs are spent on imported bone grafts for bone injuries, tumors, and other pathologies associated with defective fracture healing. The current study is aimed at developing a more strategic approach in order to speed-up recovery after bone damage. This will reduce the risk of fatal surgical complications and improve the quality of life of people affected with such fractures. 3D scaffolds loaded with cheap nano-particles that possess an osteogenic effect were prepared by nano-electrospinning. The Microstructure and morphology characterizations of the 3D scaffolds were monitored using scanning electron microscopy (SEM). The physicochemical characterization was investigated using X-ray diffractometry (XRD) and infrared spectroscopy (IR). The Physicomechanical properties of the 3D scaffold were determined by a universal testing machine. The in vitro bioactivity of the 3D scaffold was assessed in simulated body fluid (SBF). The bone-bonding ability of novel 3D scaffolds was also evaluated. The obtained nanofibrous scaffolds demonstrated promising microstructure, physicochemical and physicomechanical features appropriate for enhanced bone regeneration. Therefore, the utilized nanomaterials loaded with the drug are greatly recommended as cheap alternatives to growth factors.

Keywords: bone regeneration, cheap scaffolds, nanomaterials, active molecules

Procedia PDF Downloads 188
495 Attitudes towards Bilingualism: The Case of Cameroon

Authors: Patricia W. Ngassa

Abstract:

Language attitude is an area arousing the interest of linguists who are continuously discovering new methods of detecting attitudes. This paper problematizes Cameroonians’ alleged tendency of neglecting home languages and considering Bilingualism in borrowed languages as more important. 30 questionnaires were used to know attitudes of parents towards bilingualism and our home languages. Results revealed that our borrowed official languages are considered more important than home languages.

Keywords: bilingualism, mother tongue, Cameroon, official language

Procedia PDF Downloads 623
494 Design of a Small Mobile PV Driven RO Water Desalination Plant to be Deployed at the North West Coast of Egypt

Authors: Hosam A. Shawky, Amr A. Abdel Fatah, Moustafa M. S. Abo ElFad, Abdel Hameed M. El-Aassar

Abstract:

Water desalination projects based on reverse osmosis technology are being introduced in Egypt to combat drinking water shortage in remote areas. Reverse osmosis (RO) desalination is a pressure driven process. This paper focuses on the design of an integrated brackish water and seawater RO desalination and solar Photovoltaic (PV) technology. A small Mobile PV driven RO desalination plant prototype without batteries is designed and tested. Solar-driven reverse osmosis desalination can potentially break the dependence of conventional desalination on fossil fuels, reduce operational costs, and improve environmental sustainability. Moreover, the innovative features incorporated in the newly designed PV-RO plant prototype are focusing on improving the cost effectiveness of producing drinkable water in remote areas. This is achieved by maximizing energy yield through an integrated automatic single axis PV tracking system with programmed tilting angle adjustment. An autonomous cleaning system for PV modules is adopted for maximizing energy generation efficiency. RO plant components are selected so as to produce 4-5 m3/day of potable water. A basic criterion in the design of this PV-RO prototype is to produce a minimum amount of fresh water by running the plant during peak sun hours. Mobility of the system will provide potable water to isolated villages and population as well as ability to provide good drinking water to different number of people from any source that is not drinkable.

Keywords: design, reverse osmosis, photovoltaic, energy, desalination, Egypt

Procedia PDF Downloads 573
493 Sun-Driven Evaporation Enhanced Forward Osmosis Process for Application in Wastewater Treatment and Pure Water Regeneration

Authors: Dina Magdy Abdo, Ayat N. El-Shazly, Hamdy Maamoun Abdel-Ghafar, E. A. Abdel-Aal

Abstract:

Forward osmosis (FO) is one of the important processes during the wastewater treatment system for environmental remediation and fresh water regeneration. Both Egypt and China are troubled by over millions of tons of wastewater every year, including domestic and industrial wastewater. However, traditional FO process in wastewater treatment usually suffers low efficiency and high energy consumption because of the continuously diluted draw solution. An additional concentration process is necessary to keep running of FO separation, causing energy waste. Based on the previous study on photothermal membrane, a sun-driven evaporation process is integrated into the draw solution side of FO system. During the sun-driven evaporation, not only the draw solution can be concentrated to maintain a stable and sustainable FO system, but fresh water can be directly separated for regeneration. Solar energy is the ultimate energy source of everything we have on Earth and is, without any doubt, the most renewable and sustainable energy source available to us. Additionally, the FO membrane process is rationally designed to limit the concentration polarization and fouling. The FO membrane’s structure and surface property will be further optimized by the adjustment of the doping ratio of controllable nano-materials, membrane formation conditions, and selection of functional groups. A novel kind of nano-composite functional separation membrane with bi-interception layers and high hydrophilicity will be developed for the application in wastewater treatment. So, herein we aim to design a new wastewater treatment system include forward osmosis with high-efficiency energy recovery via the integration of photothermal membrane.

Keywords: forword, membrane, solar, water treatment

Procedia PDF Downloads 81
492 Effects of Al on Microstructure and Magnetic Properties of (Nd,Pr)-(Fe,Co)-B Alloys Prepared by Mechanical Alloying

Authors: Rahim Sabbaghizadeh, Mansor Hashim, Nooshin Shourcheh

Abstract:

Nanocrystalline Nd8Pr2Fe79-xCo5B6Alx (x=0, 1, 2, 3) magnets were prepared by mechanical alloying and respective heat treatment, and the effects of the addition of Al on the microstructure and magnetic properties of Nd-Fe-Co-B alloy were studied. The changes in the nanostructure and magnetic properties were examined by X-Ray diffraction, combined with Field Emission Scanning electron microscopy (FeSEM) and vibrating sample magnetometer (VSM). Addition of Al was found to be effective for improving the coercivity and the hysteresis squareness in Nd–Fe–Co–B magnets without decreasing much the remanent magnetization.

Keywords: mechanical alloying, nanocrystalline, Nd-Fe-B, vibrating sample magnetomete

Procedia PDF Downloads 515
491 Preparation, Characterization, and Antimicrobial Activity of Carboxymethyl Chitosan Schiff Bases with Different Benzaldehyde Derivatives

Authors: Nadia A. Mohamed, Magdy W. Sabaa, Ahmed H. H. El-Ghandour, Marwa M. Abdel-Aziz, Omayma F. Abdel-Gawad

Abstract:

Eighteen carboxymethyl chitosan (CMCh) schiff bases and their reduced derivatives have been synthesized. They were characterized by spectral analyses (FT-IR and H1-NMR) and scanning electron microscopy observation. Their antibacterial activities against Streptococcus pneumoniae (RCMB 010010), Bacillis subtilis (RCMB 010067), as Gram positive bacteria and Escherichia coli (RCMB 010052) as Gram negative bacteria and the antifungal activity against Aspergillus fumigatus (RCMB 02568), Geotricum candidum (RCMB 05097), and Candida albicans (RCMB 05031) were examined using agar disk diffusion method. The results demonstrate how the antibacterial and the antifungal activity are clearly affected by both the nature and position of the substituent groups in the aryl ring of the prepared derivatives. CMCh-4-nitroBenz Schiff base and its reduced form show higher antimicrobial activity comparing with other para substituted derivatives. CMCh-4-nitroBenz Schiff base: 18.3, 17, and 15.6 mm against Bacillis subtilis, Streptococcus pneumonia, and Escherichia coli respectively and 16.2, 17.3, and 16.4 mm against Aspergillus fumigates, Geotricum candidum, and Candida albicans respectively. CMCh-4-nitroBenz reduced form: 19.5, 18.7, and 16.2 mm against Bacillis subtilis, Streptococcus pneumonia, and Escherichia coli respectively and 17.5, 19.5, and 17.4 mm against Aspergillus fumigates, Geotricum candidum, and Candida albicans respectively. Also CMCh-3-bromoBenz show good results; CMCh-3-bromoBenz schiff base: 19.2, 16.9, and 14.6 mm Bacillis subtilis, Streptococcus pneumonia, and Escherichia coli respectively and 18.4, 17.6, and 15.9 mm against Aspergillus fumigates, Geotricum candidum, and Candida albicans respectively.

Keywords: chitosan, schiff base, minimum inhibition concentration, antimicrobial activity

Procedia PDF Downloads 460