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Facies Analysis and Biostratigraphy of the Miocene Sequence,Cairo-Suez District,Egypt

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Journal of Earth Science 2017年第1期28卷 1-8页

作者： Abdelbaset el-Sorogy Mohamed Abd-elmoneim ahmed Mowafi Khaled Al-Kahtany Hisham Gahlan Department of Geology and Geophysics College of Science King Saud University Riyadh 11451 Saudi Arabia Geology Department Faculty of Science Zagazig University Zagazig 44519 Egypt

Miocene siliciclastic-carbonate deposits are widely exposed in Cairo-Suez District, Egypt. These deposits are underlain and overlain by continental sediments of Oligocene and post Miocene, respectively. Three stratigraphic sections were investigated at Gabals Geneife, Homeira and Gharra. Lithostrtigraphically, the Miocene sequence could be differentiated into two main rock units representing shallow deposits with relatively intermittent deep marine incursions. These are from base to top, Gharra Formation and Genefe Formation. Detailed macrofossils investigations led to the recognition of four macrofossil zones, namely Alectryonella plicatula-Crassostrea frondosa Range Zone, Echinolampas amplus-Scutella ammonis Range Zone, Chlamys（Macrochlamys） sardoa-Chlamys（Argopecten） submalvinae Range Zone, and Chlamys gentoni-Pecten（Oppenheimopecten） benedictus-Pecten（P.） ziziniae Assemblage Zone. Microfacies analysis and identified taxa indicated that the Miocene sequence was deposited in transgressive-regressive cycles ranged from near shore, warm shallow inner to middle shelf marine environments with storm influence during the accumulation of the oyster banks.

关键词： facies analysis biostratigraphy Miocene Cairo-Suez District Egypt.

Acaricidal activities of some essential oils and their monoterpenoidal constituents against house dust mite,Dermatophagoides pteronyssinus (Acari:Pyroglyphidae)

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第12期7卷 957-962页

作者： SAAD el-Zemity HUSSIEN Rezk SAHER Farok ahmed Zaitoon Department of Pesticide Chemistry Faculty of Agriculture Alexandria University Alexandria 21-545 Egypt Department of Economic Entomology Faculty of Agriculture Alexandria University Alexandria 21-545 Egypt

The acaricidal activities of fourteen essential oils and fourteen of their major monoterpenoids were tested against house dust mites Dermatophagoides pteronyssinus. Five concentrations were used over two different time intervals 24 and 48 h under laboratory conditions. In general, it was noticed that the acaricidal effect based on LC50 of either essential oils or monoterpenoids against the mite was time dependant. The LCso values were decreased by increasing of exposure time. Clove, matrecary, chenopodium, rosemary, eucalyptus and caraway oils were shown to have high activity. As for the monoterpenoids, cinnamaldehyde and chlorothymol were found to be the most effective followed by citronellol. This study suggests the use of the essential oils and their major constituents as ecofriendly biodegradable agents for the control of house dust mite, D. pteronyssinus.

关键词： Natural acaricides Essential oils Monoterpenoids House dust mite Dermatophagoides pteronyssinus

Classification of sites according to gamma radiation levels in ambient air using GIS and datamining techniques

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Radiation Detection Technology and Methods 2018年第2期2卷 75-83页

作者： Mazhar Mahmoud Hefnawi ahmed Yousef el-Haseib Radiation Safety Department Egyptian Nuclear and Radiological Regulatory Authority(ENRRA)3 Ahmed El-Zomor St.Nasr CityP.O.Box 7551Cairo 11762Egypt Sitting and Environment Department Egyptian Nuclear and Radiological Regulatory Authority(ENRRA)3 Ahmed El-Zomor St.Nasr CityP.O.Box 7551Cairo 11762Egypt

Purpose This work uses the data which represent the measurements of the gamma radiation levels in ambient air from many gamma monitoring stations that are distributed in many sites to classify the regions which cover these sites according to these *** The processes of the classification are:dividing the range of measurements to several intervals,making interpolation for all regions that cover all gammamonitoring stations,representing the interpolation information in the map using geographic information systems technology and finally classifying all the sites on this map according to the determined intervals by using data mining techniques via interpolation *** and Importance This method is implemented for determining the background of gamma radiation levels for many sites in *** background is necessary for many environmental researches because it is useful for making risk assessment evaluation for any site in *** The output result from this implementation shows that most sites in Egypt have been classified within three intervals:first interval is from 2.02E−2 to4.75E−2μSv/h with 47.11%of Egypt area,second interval is from 4.75E−2 to8.85E−2μSv/h with 40%of Egypt area and third interval is from 8.85E−2 to 1.42E−1μSv/h with 6.82%of Egypt *** This method is more useful than other traditional methods because the results from this method show that this method saves more effort,time and cost than other methods.

关键词： GIS Data mining Environmental classification Data modeling

La^3+ doped LiCo0.25Zn0.25Fe2O4 spinel ferrite nanocrystals:Insights on structural,optical and magnetic properties

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Journal of Rare Earths 2021年第1期39卷 75-82,I0003页

作者： M.I.A.Abdel Maksoud ahmed el-Ghandour A.H.Ashour M.M.Atta Soraya Abdelhaleem ahmed H.el-Hanbaly Ramy Amer Fahim Said M.Kassem M.S.Shalaby A.S.Awed Materials Science Lab. Radiation Physics DepartmentNational Center for Radiation Research and Technology(NCRRT)Atomic Energy AuthorityCairoEgypt Center Photonics and Smart Materials(CPSM) Zewail City of Science and TechnologyOctober Gardens6th of October CityGizaEgypt Polymers Physics Lab. Radiation Physics DepartmentNational Center for Radiation Research and Technology(NCRRT)Atomic Energy AuthorityCairoEgypt Egyptian Nuclear and Radiological Regulatory Authority CairoEgypt Radiation Protection and Dosimetry Department National Center for Radiation Research and Technology(NCRRT)Atomic Energy AuthorityCairoEgypt Magnetic and Thermal Lab Solid State&Accelerators DepartmentNational Center for Radiation Research and TechnologyAtomic Energy AuthorityNasr CityCairoEgypt Higher Institute for Engineering and Technology ManzalaDakahliaEgypt

This paper addresses the manipulation of structural,morphology,optical and magnetic properties of LiCo0.25Zn0.25Fe2 O4 ferrite via incorporation of different proportions of La^3+at the expense of iron ions using a sol-gel *** samples were characterized using the X-ray diffraction technique(XRD),Fourier transform infrared(FT-IR)spectroscopy,the energy dispersive X-ray spectra(EDX),inductively coupled plasma optical emission spectroscopy(ICP-OES),high resolution scanning electron microscopy(SEM),Brunauer-Emmett-Teller(BET)surface area analysis,ultraviolet-diffuse reflectance spectroscopy(UV-DRS),and vibrating sample magnetometer(VSM)*** Rietveld refinements of the samples indicate that at higher concentrations of La^3+,nanostructures with dual phase,*** spinel and orthorhombic LaFeO3 perovskite with space group(Pbnm)*** studies show that the energy band gap(Eg)of the bare LiCo0.25Zn0.25Fe2 O4 ferrite sample(2.18 eV)reaches up to 2.47 eV at x=0.06 and above this concentration,it drops sharply to 2.00 *** the saturation magnetization and the coercivity of LiCo0.25Zn0.25LaxFe2-xO4 are lower than that of LiCo0.25Zn0.25Fe2 O4 ***,the superparamagnetic nature and low values of saturation magnetization and coercivity of LiCo0.25Zn0.25LaxFe2-xO4 NPs are suitable to be applied in transformers core.

关键词： Li-Co-Zn ferrite Superparamagnetic nature Optical properties Magnetic behavior Transformers core Rare earths

Magnetic field induction and magnetic force distribution profiles in plasma focus discharge device

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Plasma Science and Technology 2021年第7期23卷 110-120页

作者： A A LASHIN T M ALLAM H A el-SAYED Kamal M ahmed S A WARD H M SOLIMANand M A ABOUelATTA Plasma and Nuclear Fusion Department Nuclear Research CentreEgyptian Atomic Energy AuthorityInshas 13759Egypt Faculty of Engineering Delta University for Science and TechnologyGamasa 11152Egypt electrical Engineering Department Faculty of Engineering at ShoubraBenha UniversityCairo 11629Egypt

We report a simple-to-perform technique to investigate the distribution of the azimuthal magnetic field induction,Bθ,and the induced magnetic force acting on the plasma current sheath(PCS)in a plasma focus(PF)*** in situ measurement technique can undoubtedly be beneficial when other fast-imaging techniques are not *** are not *** work was conducted in the low-energy Mather-type EAEA-PF1 device operated in *** axial distribution(Bθ)z along the coaxial electrodes system was measured with a four magnetic-probe set technique at different radial distances(r=2.625×10^(−2) to 4.125×10^(−2) m)within the annular space between the coaxial electrodes during the 1st and 2nd half cycles of the discharge current waveform,where inner electrode of coaxial electrode system has a+ve polarity and−ve polarity,***,radial and total magnetic force distribution profiles were estimated from Bθ*** of PCS shape in terms of its inclination(curvature)angle,θ,along the axial rundown phase and the correlation between the magnetic forces per unit volume acting on the PCS,the inclination angleθof the PCS,and the formation of a powerful PF action during the 1st and 2nd half cycles is carried *** of inclination angle,θ,on total magnetic force per unit volume acting on PCS axial motion was studied,separately,during the 1st and 2nd half cycles.

关键词： plasma focus azimuthal magnetic field magnetic force inclination angle plasma current sheath

Molecular and serological prevalence of Toxoplasma gondii in pregnant women and sheep in Egypt

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Asian Pacific Journal of Tropical Medicine 2017年第10期10卷 996-1001页

作者： Hany M.Ibrahim Azza H.Mohamed ahmed A.el-Sharaawy Hend E.el-Shqanqery Department of Zoology Faculty of ScienceMenoufia UniversityShebin El-KomEgypt Clinical Pathology Unit National Liver InstituteMenoufia UniversityEgypt

Objective: To investigate molecular and serological prevalence of Toxoplasma gondii(***) in pregnant women and sheep in ***: Blood samples collected from healthy 364 pregnant women and 170 sheep were investigated for *** antibodies and parasitemia using highly specific and sensitive surface antigen(TgSAG2) based enzyme linked immunosorbent assay(elISA)and real time-polymerase chain reaction(RT-PCR).Results: Overall prevalence of *** was 51.76%, 17.65% in sheep, 33.79%, 11.81%in pregnant women, using elISA and RT-PCR *** differences in *** prevalence were observed on the basis of contact with cats or soil in pregnant women using either RT-PCR or *** pregnant women, a significant increase was detected in aged and those eating under-cooked mutton using simultaneous elISA/***: Consumption of under-cooked infected mutton is an important source of human infection and the combination of the two assays provide accurate and precise data during infection.

关键词： Toxoplasmosis RT-PCR elISA Pregnant-women Sheep

Wind Power Prediction Based on Machine Learning and Deep Learning Models

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Computers, Materials & Continua 2023年第1期74卷 715-732页

作者： Zahraa Tarek Mahmoud Y.Shams ahmed M.elshewey el-Sayed M.el-kenawy Abdelhameed Ibrahim Abdelaziz A.Abdelhamid Mohamed A.el-dosuky Faculty of Computers and Information Computer Science DepartmentMansoura UniversityMansoura35561Egypt Faculty of Artificial Intelligence Kafrelsheikh UniversityKafrelsheikh33511Egypt Faculty of Computers and Information Computer Science DepartmentSuez UniversitySuezEgypt Department of Communications and electronics Delta Higher Institute of Engineering and TechnologyMansoura35111Egypt Faculty of Artificial Intelligence Delta University for Science and TechnologyMansoura35712Egypt Computer Engineering and Control Systems Department Faculty of EngineeringMansoura UniversityMansoura35516Egypt Department of Computer Science Faculty of Computer and Information SciencesAin Shams UniversityCairo11566Egypt Department of Computer Science College of Computing and Information TechnologyShaqra University11961Saudi Arabia Department of Computer Science Arab East CollegesRiyadh13544Saudi Arabia

Wind power is one of the sustainable ways to generate renewable *** recent years,some countries have set renewables to meet future energy needs,with the primary goal of reducing emissions and promoting sustainable growth,primarily the use of wind and solar *** achieve the prediction of wind power generation,several deep and machine learning models are constructed in this article as base *** regression models are Deep neural network(DNN),k-nearest neighbor(KNN)regressor,long short-term memory(LSTM),averaging model,random forest(RF)regressor,bagging regressor,and gradient boosting(GB)*** addition,data cleaning and data preprocessing were performed to the *** dataset used in this study includes 4 features and 50530 *** accurately predict the wind power values,we propose in this paper a new optimization technique based on stochastic fractal search and particle swarm optimization(SFSPSO)to optimize the parameters of LSTM *** evaluation criteria were utilized to estimate the efficiency of the regression models,namely,mean absolute error(MAE),Nash Sutcliffe Efficiency(NSE),mean square error(MSE),coefficient of determination(R2),root mean squared error(RMSE).The experimental results illustrated that the proposed optimization of LSTM using SFS-PSO model achieved the best results with R2 equals 99.99%in predicting the wind power values.

关键词： Prediction of wind power data preprocessing performance evaluation

Review on friction stir welding of dissimilar magnesium and aluminum alloys: Scientometric analysis and strategies for achieving high-quality joints

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Journal of Magnesium and Alloys 2023年第11期11卷 4082-4127页

作者： Mohamed M.Z.ahmed Mohamed M.el-Sayed Seleman Dariusz Fydrych Gürel ÇAM Department of Mechanical Engineering College of Engineering at Al KharjPrince Sattam Bin Abdulaziz UniversityAl Kharj 11942Saudi Arabia Department of Metallurgical and Materials Engineering Faculty of Petroleum and Mining EngineeringSuez UniversitySuez 43512Egypt Faculty of Mechanical Engineering and Ship Technology Institute of Machines and Materials TechnologyGdańsk University of TechnologyGabriela Narutowicza Street 11/12Gdańsk 80-233Poland Department of Mechanical Engineering Iskenderun Technical UniversityIskenderunHatay 31200Turkiye

Magnesium and aluminum alloys continually attract interest as lightweight structural materials for transport applications. However, joining these dissimilar alloys is very challenging. The main obstacle that hinders progress in dissimilar Mg-Al joining is the formation of brittle intermetallic compounds(IMCs). As a solid-state joining technique, FSW is an excellent candidate to attenuate the deleterious IMC effects in dissimilar Al-Mg joining due to the inherent low heat inputs involved in the process. However, the IMCs, namely Al_(3)Mg_(2) and Al_(12)Mg_(17) phases, have also been reported to form during Al-Mg dissimilar FSW;their amount and thickness depend on the heat input involved;thus,the weld parameters used. Since the heat dissipated in the material during the welding process significantly affects the amount of IMCs,the heat input during FSW should be kept as low as possible to control and reduce the amount of IMCs. This review aims to critically discuss and evaluate the studies conducted in the dissimilar Al/Mg FSW through a scientometric analysis and also with a focus on the strategies recently applied to enhance joint quality. The scientometric analysis showed that the main research directions in Mg/Al FSW are the technological weldability of aluminum and magnesium during FSW, structural morphology, and mechanical properties of dissimilar welded joints. Considering the scope of application of the aforementioned joints, the low share of articles dealing with environmental degradation and operational cracking is surprising. This might be attributed to the need for well-developed strategies for obtaining high-quality and sustainable joints for applications. Thus, the second part of this review is conventional, focusing mainly on the new strategies for obtaining high-quality Mg/Al joints. It can be concluded that in addition to the necessity to optimum welding parameters to suppress the excessive heat to limit the amount and thickness of IMC formed and improv

关键词： Friction stir welding(FSW) Al-alloys Mg-alloys Dissimilar material welding Intermetallics Weld performance

Hybridization between microstructure and magnetization improvement in lead and RE co-doped BiFeO_3

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Journal of Rare Earths 2016年第5期34卷 495-506页

作者： M.A.ahmed S.F.Mansour S.I.el-Dek M.M.Karamany Materials Science Lab.(1) Physics Dept.Faculty of ScienceCairo University Physics Department Faculty of ScienceZagazig University Materials Science and Nanotechnology Dept. Faculty of Post Graduate Studies for Advanced SciencesBeni-Suef University Basic Science Dept. Faculty of EngineeringBritish University in Egypt

The crystal structure,magnetic and electrical properties of Bi（0.96）Pb（0.04） FeO3 and Bi（0.92）Pb（0.04）RE（0.04）FeO3（RE=La,Sm,Dy and Yb）polycrystalline samples were prepared by the flash autocombustion technique.X-ray diffraction（XRD）measurements show that the rare-earth doped compositions crystallized in rhombohedral symmetry of space group R3 *** undoped sample consisted needle shape particles while rare earth substitution preferred platelet like particles as clarified from high resolution transmission electron microscopy（HRTEM）.Morphological features were examined using field emission scanning electron microscopy（FESEM）.Magnetization measurements showed that Yb^3＋ samples possessed the highest room temperature saturation magnetization while when Bi^3＋ ions were substituted by La^3＋ ions,a smaller MS（0.28 emu/g）was *** coexistence of ferroelectric and magnetic transitions was detected using DSC and χM,indicating the multiferroic characteristics of Bi（0.92）Pb（0.04）RE（0.04）FeO3 *** Néel temperature shifted upwards with decreasing the ionic radius of rare earth *** correlation was established between microstructure,morphology and magnetic properties in view of the contribution of magnetocrystalline and shape anisotropy in the magnetic parameters values.

关键词： BiFeO3 multiferroic rare earths anisotropy dielectric conductivity Neel temperature