Ahmed Husseini Ibrahim - Academia.edu (original) (raw)

Papers by Ahmed Husseini Ibrahim

Journal of Magnetism and Magnetic Materials, Jul 1, 2019

Abstract In this work, the structural and magnetic properties of multiferroic La 1 - x Y x FeO 3 ... more Abstract In this work, the structural and magnetic properties of multiferroic La 1 - x Y x FeO 3 perovskites, (x = 0.00, 0.05, 0.10, 0.15, 0.20, 0.25 and 0.30) synthesized through Sol-gel auto-combustion technique were investigated.The room temperature synchrotron X-ray diffraction (XRD) analysis revealed that the all the synthesized samples consisted of the polycrystalline orthorhombic structure perovskites (space group pnma), and tolerance factor confirmed the phase stability of the prepared perovskite system.The Williamson-Hall plots based on synchrotron XRD data were employed to estimate the average particle diameter and vary from 18.8 nm to 37.5 nm.For a deeper insight into the crystal structure, high-resolution transmission microscopy imaging (HRTEM) was performed.The estimated values of crystallite size from HRTEM and synchrotron XRD data were coincident.Many of crystallographic parameters and electron density measurements were calculated by Rietveld refinement of synchrotron XRD data. La 1 - x Y x FeO 3 perovskite crystals are canted antiferromagnets with a weak ferromagnetism at room temperature.Selected Area Electron Diffraction (SAED) patterns of the investigated samples exhibited spotty ring patterns, confirming the polycrystalline character.The magnetic properties were gotten through analyzing the magnetization versus temperature M(T) and M(H) hysteresis loop which characterized by a vibrating sample magnetometer (VSM). The orthoferrite La 1 - x Y x FeO 3 crystals are a promising candidate for optical device applications in broad temperature range and high power system.

Journal of Materials Science: Materials in Electronics

Herein, we report, for the first time, the influence of the state of spin of the Cr3+ ions on the... more Herein, we report, for the first time, the influence of the state of spin of the Cr3+ ions on the structure and magnetic behavior of LaFe1−xCrxO3 (0.0 < x < 0.5) perovskite crystal structures to improve their magnetic properties for memory storage and magneto-optical application potential. A series of LaFe1−xCrxO3 (0.0 < x < 0.5) nanocrystals was prepared using the citrate-nitrate auto-combustion route. The influence of the Cr3+ ions on the structure and morphology of the LaFe1−xCrxO3 nanostructures was emphasized using X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), the selected area of electron diffraction (SAED), and scanning electron microscopy (SEM). The results revealed that the inclusion of the Cr3+ ions into the Fe3+ sites leads to an increase in the crystallite size of the LaFe1−xCrxO3 (0.0 < x < 0.5) nanocrystals, from 16.12 to 57.29 nm, to preserve their orthorhombic crystal symmetry. The phase stability and the electro...

Nanomaterials

The increase of global environmental restrictions concerning solid and liquid industrial waste, i... more The increase of global environmental restrictions concerning solid and liquid industrial waste, in addition to the problem of climate change, which leads to a shortage of clean water resources, has raised interest in developing alternative and eco-friendly technologies for recycling and reducing the amount of these wastes. This study aims to utilize Sulfuric acid solid residue (SASR), which is produced as a useless waste in the multi-processing of Egyptian boiler ash. A modified mixture of SASR and kaolin was used as the basic component for synthesizing cost-effective zeolite using the alkaline fusion-hydrothermal method for the removal of heavy metal ions from industrial wastewater. The factors affecting the synthesis of zeolite, including the fusion temperature and SASR: kaolin mixing ratios, were investigated. The synthesized zeolite was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), particle size anal...

MEJ. Mansoura Engineering Journal

The Egyptian Journal of Plastic and Reconstructive Surgery

Background: Pressure ulcer reconstruction remains a great challenge for plastic surgeons because ... more Background: Pressure ulcer reconstruction remains a great challenge for plastic surgeons because of their high postoperative complication and recurrence rates. Commonly these ulcers are reconstructed with random pattern flaps or myocutaneous flaps. Gluteal artery perforator flaps have evolved in the last few decades and became popular in reconstructing pressure ulcers in the gluteal region because they preserve the gluteal muscle, allowing for revision in cases of recurrence. Objective: To evaluate the use of gluteal artery perforator flaps in reconstructing pressure ulcers of the gluteal region as regards aesthetic outcome, postoperative complications and patients' psychological satisfaction. Patients and Methods: Our study was conducted on 15 patients presented with grade IV pressure ulcers in the gluteal region, in which their ulcers were reconstructed with gluteal artery perforator flaps. Results: Twelve (80%) patients healed eventually without major complications. Two (13.3%) patients had wound edge dehiscence, and only one (6.7%) patient had a donor site wide scar. Patients were evaluated as regards aesthetic outcomes and patients' psychological satisfaction, and the overall results were satisfactory. Conclusion: The superior and inferior gluteal artery perforator flaps, with their safe anatomical basis, less morbidity and versatility in designs, are reliable and effective alternatives in reconstructing pressure ulcers of the gluteal region.

Frontiers in Plant Science

Microorganism-related technologies are alternative and traditional methods of metal recovery or r... more Microorganism-related technologies are alternative and traditional methods of metal recovery or removal. We identified and described heavy metal–resistant bacteria isolated from polluted industrial soils collected from various sites at a depth of 0–200 mm. A total of 135 isolates were screened from polluted industrial soil. The three most abundant isolate strains resistant to heavy metals were selected: Paenibacillus jamilae DSM 13815T DSM (LA22), Bacillus subtilis ssp. spizizenii DSM 15029T DSM (MA3), and Pseudomonas aeruginosa A07_08_Pudu FLR (SN36). A test was conducted to evaluate the effect of (1) isolated heavy metal–resistant bacteria (soil application), (2) a foliar spray with silicon dioxide nanoparticles (Si-NPs), and (3) moringa leaf extract (MLE) on the production, antioxidant defense, and physio-biochemical characteristics of spinach grown on heavy metal–contaminated soil. Bacteria and MLE or Si-NPs have been applied in single or combined treatments. It was revealed tha...

Journal of Material Cycles and Waste Management

Radiation Physics and Chemistry, 2022

American Journal of Materials Science, 2014

The two polymorph modifications of LiFe5O8, fine particles were successfully prepared by ceramic ... more The two polymorph modifications of LiFe5O8, fine particles were successfully prepared by ceramic technique at pre-sintering temperature of 500℃ and the pre-sintered material was crushed and sintered finally in the open air at 1000℃. The structural and microstructural evolutions of the nanophase were studied using powder X-ray diffraction (XRD) and the Rietveld method. The two polymorphous LiFe5O8 includes the ordered phase, termed α-LiFe5O8, with a primitive cubic unit cell (space group P4332, a=8.337 A) in which the Fe 3+ ions are at octahedral 12d and tetrahedral 8c sites, and Li + ions occupy only the octahedral 4b positions in the cubic primitive unit cell and disordered face centered cubic structure, termed β-LiFe5O8 (space group Fd-3m, a = 8.3333 A), The refinement of XRD results revealed the presence of mixed and nearly inverse spinel nanocrystalline Li-ferrite phases. Transmission electron microscopy (TEM) revealed that the particles of the prepared samples were spherical in...

INTERNATIONAL JOURNAL OF CIVIL ENGINEERING AND TECHNOLOGY (IJCIET), 2021

Management of educational building assets is one of the most complicated factors because it has a... more Management of educational building assets is one of the most complicated factors because it has a bigger number of related and unrelated criterions. Analytic hierarchy process (AHP) as a decision-making technique widely deal with many decision is problems that have bigger number of criterions. This paper proposes AHP method to define the judgment matrix of related and unrelated criterions that is used to calculate the relative weights (RWs) of each criterion. Analytic network process (ANP) was also used to calculate the RWs of the interrelated building categories (architectural, mechanical, and electrical). Such RWs can be used by managers for physical condition assessment of an educational building. The educational building hierarchy are divided into five levels. Each level is then defined in a judgment matrix to calculate its RWs. Then. The consistency of such judgment matrix has been evaluated to ensure that the RWs' results are acceptable. As concluded in the space level of the building hierarchy, the classroom space type that includes most of the education processes had the highest relative weight (RW=26.76%) followed by the bathrooms (RW=26.14%) and corridors and stairs (RW=25.77%). On the other hand, the cafeteria space type was the least relative weight (RW=1.58%) among all other space types. AHP technique provided an improved approach to calculate the RWs of each criterion affecting physical condition of educational building in Egypt.

International Journal of Pediatrics & Neonatal Care, 2019

JOURNAL OF ADVANCES IN PHYSICS, 2017

Air pollution produced by the direct burning of fossil fuels is a serious problem. Therefore, the... more Air pollution produced by the direct burning of fossil fuels is a serious problem. Therefore, there is a vital demand for renewable and clean fuel replacements for future energy source. Hydrogen, which exhibits high calorific value and is a clean burning product, could be the first choice in the future, as it is a good-looking fuel for fuel cells where the electric energy is directly gotten by the electrochemical reactions of hydrogen and oxygen. Rapidly solidified Al100-x-Snx alloy X= (0, 25, 55, 75 all in wt.%) was prepared using melt spinning technique at 800 ÂºC. The structural and microstructural evolutions of the phases have been studied using X-ray powder diffraction (XRD) and the Rietveld method. Al45Sn55 alloy shows the best volume of hydrogen generation which is (531 ml), this alloy has the highest number of grains (1096) than other prepared alloys in its surface which examined through a Scanning electron microscope (SEM) and analyzed using an SPM data visualization and an...

Abu Dhabi International Petroleum Exhibition & Conference, 2018

It is a challenge to drill a highly deviated or horizontal hole in high permeable formations. Hig... more It is a challenge to drill a highly deviated or horizontal hole in high permeable formations. High differential pressures may lead to several problems like tight holes, wellbore instability, differential sticking and mud loss while drilling across these permeable or fractured formations. It was always preferred to drill these wells with Oil base muds which showed some success. While operators always prefer the standard solution, which is casing isolation for problematic sections, challenges have increased due to continuously drilling in depleted reservoirs which leads to considerable nonproductive time. The other solution to overcome such problematic sections was to re-design a fluid system that would target drilling through serious of highly permeable sand and shale formations. The fluid system would primarily address shale inhibition along with effective bridging, minimizing pore pressure transmission and wellbore strengthen with increased hoop stress in the wellbore. Software modelling and permeability plugging tests were performed to evaluate the fluid behavior under downhole conditions and to predict the characteristics of induced micro fractures based on rock mechanics. Porosity, permeability and induced micro fractures were considered to optimize the bridging mechanism. It was identified that normal bridging solutions involving calcium carbonates and graphite material were not enough to address the pore pressure transmission problem. It was essential to include a micronized sealing deformable polymer along with normal bridging material was effective in plugging pore throats and minimizing fluid invasion. The deformable polymer component is able to re-shape itself to fit a broad range of pore throat sizes which was previously unattainable with conventional bridging technology which was confirmed by particle plugging tests. A one well was identified to be drilled in highly depleted reservoir at an inclination of almost 45 degrees. The section involving the highly depleted and permeable sand involved drilling highly stressed shale formations which requires high mud weight for their stability. This was the first attempt on a high-angle well with development drilling operations in Kuwait and was performed to facilitate the successful drilling of the reservoir. Drilling and logging were successfully performed along with logging and LWD runs with no recordable differential sticking or losses incidents. This paper also presents 2 successful applications in the same field with the application of proper bridging and utilization of deformable sealing polymer to address drilling problems through highly depleted and permeable formations while managing over balance of 3500 psi across them.

JOURNAL OF ADVANCES IN PHYSICS, 2016

The physical properties of ferrites are verysensitive to microstructure, which in turn critically... more The physical properties of ferrites are verysensitive to microstructure, which in turn critically dependson the manufacturing process.Nanocrystalline Lithium Stannoferrite system Li0.5+0.5XFe2.5-1.5XSnXO4,X= (0, 0.2, 0.4, 0.6, 0.8 and 1.0) fine particles were successfully prepared by double sintering ceramic technique at pre-sintering temperature of 500oC for 3 h andthepre-sintered material was crushed and sintered finally in air at 1000oC.The structural and microstructural evolutions of the nanophase have been studied using X-ray powder diffraction (XRD) and the Rietveld method.The refinement results showed that the nanocrystalline ferrite has a two phases of ordered and disordered phases for polymorphous lithium Stannoferrite.The particle size of as obtained samples were found to be ~20 nm through TEM that increases up to ~ 85 nmand isdependent on the annealing temperature. TEM micrograph reveals that the grains of sample are spherical in shape. (TEM) analysis confirmed the X-ray ...

ACS applied materials & interfaces, Jan 20, 2018

A facile and versatile method is reported for the inclusion of gold nanoparticles (AuNPs) within ... more A facile and versatile method is reported for the inclusion of gold nanoparticles (AuNPs) within a monolithic metal-organic framework (HKUST-1 MOF). Simple addition of stabilized colloidal AuNPs solution to the reaction mixture at the early stages of the formation of the MOF monolith resulted in quantitative uptake of the AuNPs within the MOF matrix. Several characterization techniques including solution and solid UV-vis spectroscopy, TEM, and XRD indicated the successful immobilization of the AuNPs. Controllable loading of AuNPs was also demonstrated, where gas sorption measurements indicated the maintained microporosity of the AuNPs-containing monoliths. This methodology has wide potential applications in demanding technologies, including sensing and catalysis, where monolithic materials of controllable physicochemical properties can be readily accessible through pore size and guest selectivity of the host MOF matrix controlling access of guest molecules to immobilized AuNPs.

Pharmaceutical Development and Technology, 2017

The objective of this study was to enhance physiochemical properties as well as oral bioavailabil... more The objective of this study was to enhance physiochemical properties as well as oral bioavailability of the poorly water soluble drug fenofibrate (FB), through preparation of amorphous solid dispersions (ASDs). ASDs were prepared via freeze drying using polyvinylpyrrolidone (PVP) K30 and poloxamer 188 as hydrophilic carriers. Formulations were optimized by 3 2 full factorial design (FFD) with PVP−K30 level (X 1) and poloxomer 188 level (X 2) as independent variables and particle size (Y 1), zeta potential (Y 2), drug content (Y 3) and dissolution rate (T90, (Y 4)) as dependent variables. Optimized FB nanoparticles were physicochemically evaluated and formulated into lyophilized sublingual tablets. Pharmacokinetic, pharmacodynamic and histological finding of optimized formulation were performed on rabbits. Y 1 and Y 4 were significantly affected by independent variables while Y 2 and Y 3 were not affected. Physicochemical characterization showed the drug was in amorphous state, nanometer range and pharmacophore of FB was preserved. Administration of optimized FB tablets to rabbits with fatty liver led to significant reduction (P < 0.001) in serum lipids. Moreover, histological analysis of liver specimens confirmed the improved efficacy in animals with fatty liver. In this study, we confirmed that ASDs of FB had beneficial effects on managing fatty liver and serum lipids level in hyperlipidemic rabbits.

International Journal of Cloud Computing, 2016

Cloud computing is currently playing an important role in different applications. Deploying graph... more Cloud computing is currently playing an important role in different applications. Deploying graphical processing units (GPUs) as a resource in clouds constitutes a major challenge. As the number and the scale of internet services increase, the services running on a cloud computing environment also increase. These services could have been efficiently improved in terms of a service level agreement (SLA) if we could make use of the GPUs architectures in the cloud infrastructure. Cloud providers currently offer GPUs as an infrastructure as a service (IaaS). Providing GPUs in another context such as software as a service (SaaS) requires a resource allocation algorithm. This paper proposes a resource allocation algorithm (RAA) for GPUs in the cloud environment. The proposed RAA will provide a way for cloud providers to offer GPUs in a SaaS context. The RAA is based on the load balancing mechanism trying to fully utilise all the GPUs resources. This paper also investigates the suitability of the RAA by conducting a video enhancement service on a private cloud. It shows that the proposed algorithm provides scalability and enhancements in terms of a SLA.

Menoufia Medical Journal, 2014

Background Mortality rates are important outcome parameters after burn injury and can serve as ob... more Background Mortality rates are important outcome parameters after burn injury and can serve as objective endpoints for quality control. Causes of death after severe burn have changed over time, but the exact distribution of causes of death remains unknown. Objective The aim of the study was to estimate the mortality rates and determine the causes of death in patients admitted to the Burn Center of the Faculty of Medicine, Menofia University, between 1 January 2006 and 31 June 2010. Patients and methods Between January 2006 and June 2010, 516 patients were enrolled. A predesigned questionnaire was used to collect data about percentage of burn, site of burn, and inhalation injury as well as data about age, sex, burnt area, occurrence, and causes of death. Results Of the 516 patients included, 96 died, giving an overall mortality rate of 18.6%. The main cause of death was multiorgan failure, which accounted for 48.1% of the mortality cases. Septicemia caused about 27% of deaths, burn shock led to 19.7% of deaths, and other causes were the reason for 5.2% of mortality cases. Comparison of the overall mortality during 2006-2010 with that observed in a previous study conducted in the same unit during 2002-2004 revealed a decrease in rate (24.1-18.6%). Conclusion and recommendations Mortality rate among burn patients is influenced by several risk factors such as age, total body surface area involved, and the presence of inhalation injury. The mortality rate from severe burns has decreased but remains high despite improvements in burn care. Early fluid resuscitation, early detection and correction of any laboratory defects, nutritional support, diagnosis and treatment of inhalation injury, and prevention of burn-related infections are recommended in the treatment of acute burn.

Volume 4: Dynamics, Control and Uncertainty, Parts A and B, 2012

There has been growing interest to use composites in load carrying structures where high strength... more There has been growing interest to use composites in load carrying structures where high strength and light weight are of major concern, e.g., sports, automobiles and aircraft industries. Despite extensive research in the last two decades, mechanical behavior of composite structures subject to contact and impact loading is still not well understood. It is well known that composites are highly vulnerable to various modes of failure and damage due to impact/contact by foreign objects. Such impact/contact events are not only dependent on the material behavior but also on the dynamics of the structure. Although some of the currently available Finite Element (FE) packages are capable of simulating mechanical behavior of composite structures subject to impact, it requires extensive training and in-depth knowledge to obtain an adequate model with acceptable efficiency. Several nonlinear FE models have the ability to capture composite damage due to impact/contact including internal delamina...

Physica Status Solidi (a), 1989