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Reduced Differential Transform Method for Solving Nonlinear Biomathematics Models

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Computers, Materials & Continua 2019年第9期61卷 979-994页

作者： K.A.Gepreel A.M.S.Mahdy M.S.mohamed A.Al-Amiri Department of Mathematics Faculty of ScienceTaif UniversityTaif26571Saudi Arabia Department of Mathematics Faculty of ScienceZagazig UniversityZagazig44519Egypt Department of Mathematics Faculty of ScienceAl-Azher UniversityNasr CityCairo11884Egypt Department of Mathematics Faculty of ScienceBisha UniversityBisha61922Saudi Arabia

In this paper,we study the approximate solutions for some of nonlinear Biomathematics models via the e-epidemic si1I2R model characterizing the spread of viruses in a computer network and siR childhood disease *** reduced differential transforms method(RDTM)is one of the interesting methods for finding the approximate solutions for nonlinear *** apply the RDTM to discuss the analytic approximate solutions to the si1I2R model for the spread of virus HCV-subtype and siR childhood disease *** discuss the numerical results at some special values of parameters in the approximate *** use the computer software package such as Mathematical to find more iteration when calculating the approximate *** results and discussed quantitatively are presented to illustrate behavior of the obtained approximate solutions.

关键词： Reduced differential transforms method nonlinear biomathematics models si1I2R model siR model analytic approximate solutions qualitative analysis stability and equilibrium.

Biological Control of Root-Knot Nematode Meloidogyne incognita in Psoralea corylifolia Plant by Enhancing the Biocontrol Efficacy of Trichoderma harzianum Using Press Mud

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Phyton-International Journal of Experimental Botany 2022年第8期91卷 1757-1777页

作者： Yasar Nishat Mohammad Danish Heba I.mohamed Hisamuddin Shaikh Abeer Elhakem Section of Plant Pathology and Nematology Department of BotanyAligarh Muslim UniversityAligarh202002India Department of Biological and Geological Sciences Faculty of EducationAin Shams UniversityCairo11341Egypt Department of Biology College of Science and Humanities in Al-KharjPrince Sattam Bin Abdulaziz UniversityAl-Kharj11942Saudi Arabia

Meloidogyne incognita is a plant pathogen causing root-knot disease and loss of crop *** present study aimed to use Trichoderma harzianum as a biocontrol agent against plant-parasitic nematodes and used press mud,which is a solid waste by-product of sugarcane,as a biocontrol agent and ***,the combined application of *** and press mud may enhance nematode control and plant *** analysis of press mud using scanning electron microscopy(SEM)integrated with an Energy Dispersive X-ray(EDX)analyzer revealed the presence of different elements such as C,O,Mg,si,P,K,Ca,Cu and *** addition,a greenhouse study was conducted to investigate the combined effects of press mud and *** on *** reproduction and growth and the biochemical features of Psoralea *** results showed that plant length,dry biomass,leaf area,the number of seeds per plant,chlorophyll a,chl b,carotenoid content,nitrate reductase,carbonic anhydrase,and nitrogen content were significantly increased(P≤0.05)in the T2 plants(plants were treated with 100 g of press mud+50 mL *** before one week of *** inoculation),over inoculated plants(IC).Antioxidant enzyme activity of ascorbate peroxidase(APX),catalase(CAT),peroxidase(POD),and superoxide dismutase(SOD)in the foliage of *** was significantly increased when plants were treated with press mud+***.A significant reduction in the number of egg masses,nematode population,and root-knot index(RKI)was found in plants with T2 *** results suggest that the combined application of *** and press mud has the potential to control the *** infection and can be used as an environmentally safe alternative to chemical nematicides and also help in the removal of sugarcane waste that causes environmental pollution.

关键词： Growth improvement antioxidant enzymes nitrate reductase carbonic anhydrase root-knot index

E-shaped wideband plasmonic nantennas with linear and dual-linear polarizations

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Photonics Research 2015年第4期3卷 140-145页

作者： mohamed HEl Sherif mohamed HBakr Ezzeldin ASoliman McMaster University Department of Electrical and Computer EngineeringHamiltonOntario L8S4K1Canada The American University in Cairo Department of PhysicsAUC AvenueP.O.Box 74New Cairo 11835Egypt

In this paper we present a novel nanoantenna(nantenna) design for energy harvesting. The nantenna has an 'E'shape and is placed on a si O2 substrate. Its operation is based on the excitation of surface plasmon polaritons through the gold arms of the E shape. By varying the lengths and widths of the arms, two overlapping working bandwidths can be achieved. This results in a wideband behavior characterized by a full width at half-maximum of about 2.2 μm centered around 3.6 μm. Two orthogonal E nantennas are placed perpendicular to each other to realize a dual-polarized nantenna. This nantenna can receive the two incident polarizations at two separate gap locations with very high isolation. The proposed structure can be used in several energy harvesting applications, such as scavenging the infrared heat from the Earth and other hot objects, in addition to optical communications.

关键词： E-shaped wideband plasmonic nantennas with linear and dual-linear polarizations length

Microstructural evolution,dislocation density and tensile properties of Al–6.5si–2.1Cu–0.35Mg alloy produced by different casting processes

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Journal of Materials Science & Technology 2021年第36期95卷 145-157页

作者： S.Samat M.Z.Omar A.H.Baghdadi I.F.mohamed A.Rajabi A.M.Aziz Department of Mechanical and Manufacturing Engineering Faculty of Engineering and Built EnvironmentUniversiti Kebangsaan MalaysiaBangiUKM 43600Malaysia

Al–si–Cu–Mg foundry alloys are used in casting process ***,their strength properties remain low due to their microstructural characteristics and *** this work,the microstructural characteristics,dislocation densities,and mechanical properties of Al–si–Cu–Mg cast alloys prepared through different casting methods were studied *** casting processes,namely,gravity casting(GC),rheocasting(RC),thixoforming(Thixo),and Thixo with heat treatment,were *** GC and RC samples had mainly dendriticα-Al phase microstructures and exhibited coarse si particles and intermetallic compounds in their interdendritic *** contrast,the Thixo and heat-treated Thixo(HT-Thixo)samples exhibited microstructural refinement with uniformly distributedα-Al globules,fine fibrous si particles,and fragmented intermetallic compounds amongα-Al *** accumulation of dislocation densities increased in the Thixo sample as the strain was increased due to plastic ***,the ultimate tensile strength and yield strength of the HT-Thixo sample increased by 87%and 63%,respectively,relative to those of the GC *** cleavage fracture displayed by the GC and RC samples led to brittle ***,the Thixo and HT-Thixo samples presented dimple-based ductile fracture.

关键词： Al–si–Cu–Mg alloy Thixoforming Microstructure Mechanical property Dislocation density

SAFT-VNDN: A Socially-Aware Forwarding Technique in Vehicular Named Data Detworking

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Computers, Materials & Continua 2022年第11期73卷 2495-2512页

作者： Amel Boudelaa Zohra Abdelhafidi Nasreddine Lagraa Chaker Abdelaziz Kerrache Muhammad Bilal Daehan Kwak mohamed Bachir Yagoubi Laboratoire d’Informatique et de Mathématiques UniversitéAmar Telidji de LaghouatLaghouatAlgeria Department of Computer and Electronics Systems Engineering Hankuk University of Foreign StudiesYongin-si17035Gyeonggi-doKorea School of Computer Science and Technology Kean UniversityNJUSA

Vehicular Social Networks(VSNs)is the bridge of social networks and Vehicular Ad-Hoc Networks(VANETs).VSNs are promising as they allow the exchange of various types of contents in large-scale through Vehicle-to-Vehicle(V2V)and Vehicle-to-Infrastructure(V2I)communication *** Named Data Networking(VNDN)is an auspicious communication paradigm for the challenging VSN environment since it can optimize content dissemination by decoupling contents from their physical ***,content dissemination and caching represent crucial challenges in VSNs due to short link lifetime and intermittent connectivity caused by vehicles’high *** aim with this paper is to improve content delivery and cache hit ratio,as well as decrease the transmission delay between *** this regard,we propose a novel hybrid VNDN-VSN forwarding technique based on social communities,which allows requester vehicles to easily find the most suitable forwarder or producer among the community members in their neighborhood ***,we introduce an effective caching mechanism by dividing the content store into two parts,one for community private contents and the second one for public *** results show that our proposed forwarding technique can achieve a favorable performance compared with traditional VNDN,in terms of data delivery ratio,average data delivery delay,and cache hit ratio.

关键词： Vehicular Social Networks(VSNs) Vehicular Named Data Networking forwarding technique social communities

Microstructural Evolution of Cast Hyper-Eutectic Al-18% si Alloy during Cyclic Semi-Solid Heat Treatment

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Journal of Minerals and Materials Characterization and Engineering 2015年第5期3卷 390-398页

作者： mohamed Ramadan College of Engineering University of Hail Hail Saudi Arabia Casting Technology Lab. Central Metallurgical Research and Development Institute (CMRDI) Cairo Egypt

The cyclic semi-solid heat treatment represents a promising technique for improving microstructure and mechanical properties of a wide range of metallic alloys. In the current research the influence of cyclic semi-solid heat treatment on microstructure of Al-18% si alloy containing 0.8% Fe has been studied. All specimens were heated in an electrically heated resistance furnace with heating rate of 10°C·min-1 to 585°C. For a complete one cycle heat treatment (5 min heating time), samples after 5 min holding at 585°C were cooled to a temperature of 550°C in still air cooling and the samples were taken out immediately for water quenching. It was found that heat treatment cycles should be limited to 3 cycles or less in order to maintain fine grain size and globular structure without agglomeration and coalescence. Cyclic semi-solid heat treatment changes morphology of iron-rich intermetallics phases to be plate-like and fine plate iron-rich intermetallics phases, in stead of needle-like iron-rich intermetallics phases that are observed in as-cast samples. Cyclic heating shows a relatively higher hardness for all heating cycles compared with as-cast one due to its finer and globular structure. Cyclic semi-solid heat treatment technique results in lower coarsening rate constant compared with isothermal heat treatment one due to coarsening discontinuous effect.

关键词： Microstructural Cyclic Semi-Solid Heat Treatment Al-18% si Microstructure Hyper-Eutectic Cast

Quantification of silicon (si) and silicon Dioxide (siO₂) from the Nafud Desert-Al-Qassim Region, Kingdom of Saudi Arabia Using XRD Analysis

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Advances in Materials Physics and Chemistry 2024年第5期14卷 67-75页

作者： Nagwa Ibrahim mohamed Department of Physics College of Science Qassim University Buraydah Saudi Arabia

This research was conducted in the Qassim region, Kingdom of Saudi Arabia. The goal of this research is to determine the percentage of silicon in the Rub al-Khali desert. Samples were collected from four cities located in the Al-Qassim Region of Saudi Arabia (Uyun Al-Jawa, Al-Fuwailiq, Al-Sulaibiya, and Al-Qawara), from three distinct depths (the earth’s surface, 50 cm, and 100 cm). The percentages of silicon in these places vary between the highest value for silicon dioxide, which is 74.47 m/m%, and 34.8 m/m% for silicon in Al-Qawara city at a depth of 100 cm. We used an x-ray fluorescence (XRF) instrument to evaluate the samples. There are high percentage of both silica and silicon in the Nafud desert. Studies have shown that these ratios can help investors benefit from an element of silicon and silicon dioxide, so the sands of the Nafud desert is sufficient for extracting silicon and silica in huge quantities. This may transform the Kingdom into a leading country in the global computer technology industry that depends on silicon extracted from the desert sands, the most important of which are microcomputer data processing devices.

关键词： silica Sand Dispersive X-Ray Fluorescence (EDXRF) Analyzer Solar Cells Nafud Desert Al-Qawwarh

Experimental investigation of enhancement of carbon dioxide foam stability, pore plugging, and oil recovery in the presence of silica nanoparticles

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Petroleum Science 2019年第2期16卷 344-356页

作者： Abdul Rahim Risal Muhammad A.Manan Nurudeen Yekeen Nur Bashirah Azli Ali mohamed Samin Xin Kun Tan Department of Petroleum Engineering Faculty of Petroleum and Renewable Energy Engineering Universiti Teknologi Malaysia Institute of Hydrocarbon Recovery Universiti Teknologi PETRONAS

The influence of surface-modified silica(siO_2) nanoparticles on the stability and pore plugging properties of foams in porous media was investigated in this study. The pore plugging ability of foams was estimated from the pressure drop induced during foam propagation in porous media. The results clearly showed that the modified si02 nanoparticlestabilized foam exhibited high stability, and the differential pressure increased in porous media by as much as three *** addition of siO_2 nanoparticles to the foaming dispersions further mitigated the adverse effect of oil toward the foam pore plugging ability. Consequently, the oil recovery increased in the presence of nanoparticles by approximately 15%during the enhanced oil recovery experiment. The study suggested that the addition of surface-modified silica nanoparticles to the surfactant solution could considerably improve the conventional foam stability and pore plugging performance in porous media.

关键词： Foam Pore plugging Surface-modified nanoparticle Enhanced oil recovery

Reasons to pursue a career in medicine:a qualitative study in sierra Leone

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Global Health Research and Policy 2017年第1期2卷 13-23页

作者： Aniek Woodward Suzanne Thomas mohamed Bella Jalloh John Rees Andrew Leather King’s Centre for Global Health and Health Partnerships Division of Health&Social Care ResearchFaculty of Life Sciences&MedicineKing’s College LondonLondonUK King’s sierra Leone Partnership King’s Centre for Global Health and Health PartnershipsDivision of Health&Social Care ResearchFaculty of Life Sciences&MedicineKing’s College LondonLondonUK College of Medicine and Allied Health Sciences University of Sierra LeoneFreetownSierra Leone

Background:Many low-income and crises-affected countries like sierra Leone struggle with the recruitment and retention of their health professionals,particularly nurses and *** are multiple factors that influence the‘recruitment to retention’*** first stage of an exploration into the issues influencing the availability of qualified health care workers may focus on the aspects which influence their entry into relevant educational *** paper explores the reasons given by junior doctors in sierra Leone for wanting to become a *** also describes entry procedures into undergraduate medical ***:In-depth interviews were conducted with purposively sampled junior doctors(n=15)from the only medical school in sierra Leone in October *** diaries and two follow-up interviews were used to explore their evolving career experiences and aspirations until November *** addition,semi-structured interviews with key informants(n=20),including senior teaching staff at the medical school(n=7),were *** analysis was used to explore linkages and themes across ***:six themes were *** most commonly mentioned reasons for wanting to become a doctor were a desire to help(theme 4)and the influence of family and friends,via role modelling(theme 2)and verbal encouragement(theme 3).Other motives were an interest from a young age(theme 1),being attracted by the job prospects(theme 5),and having an intellectual and science capacity(theme 6).Junior doctors gave at least two and up to six reasons for applying to enter the medical *** were allowed entry to the medical school largely based on their previous academic ***:This study showed that multiple reasons underlie the decision to apply for entrance to medical school and the decision to enter medicine is *** findings may inform the review of future admission procedures by the medical school in sierra Leone and si

关键词： Undergraduate medical education Medical students Junior doctors Reasons Motivations Selection criteria sierra Leone