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Acta Geochimica 2020年第2期39卷 226-235页

作者： maha Ahmed mohamed Abdallah Ahmed mohamed Badr-ElDin marine Pollution Lab National Institute of Oceanography and FisheriesAlexandriaEgypt Oceanography Department Faculty of ScienceAlexandria UniversityAlexandriaEgypt

A protected semi-enclosed embayment,the Eastern Harbor(EH),is situated in the central sector of the Mediterranean coast of Alexandria,*** is a famous fishing dock and water-sport center and its importance arose after the discovery of the Ptolemaic royal quarter of ancient *** protect this national treasure and improve its environmental health,the untreated anthropogenic effluents,which continued for decades into the EH since 1992,must be totally ***,it is an important issue to continually monitor and asses the environmental status of the *** sediment texture,total organic carbon,and the accumulation,distribution,and ecological risks of Cd,Cr,Pb,As,Hg and A1 were determined with a total of 14 surficial sediments samples collected in the EH during *** contents were compared to the literature data to assess the pollution status of *** factors,Degree of contamination(mCd)and potential ecological risk were calculated as a criterion of possible *** mCd calculation produces an overall average value for a range of pollutants,in the present study the contamination factor that provides a measure of the degree of overall contamination in the surface layers in a particular sampling site may provide a better indication of the state of pollution in the EH sediments than other indicators.

关键词： Heavy metals Eastern harbor Enrichment factors Degree of contamination Potential ecological risk

Exploration of structural,optical,and photoluminescent properties of (1-x)NiCo_(2)O_(4)/xPbS nanocomposites for optoelectronic applications

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Chinese Physics B 2022年第6期31卷 663-670页

作者： Zein K Heiba mohamed Bakr mohamed Noura M Farag Ali Badawi Physics Department Faculty of ScienceAin Shams UniversityCairoEgypt Physics Department Faculty of ScienceTaibah UniversityAl-Madina al MunawarahSaudi Arabia Department of Physics College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Department of Physics University College of TurabahTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia

The(1-x)NiCo_(2)O_(4)/x PbS(0≤x≤0.2)nanocomposite samples are synthesized using the hydrothermal and thermolysis *** different phases developed in the obtained nanocomposite samples are accurately determined using the x-ray diffraction technique equipped with a *** percentage of the formed phases(NiCo_(2)O_(4)(NCO),PbS,PbSO_(4)),structural and microstructure parameters are determined using Rietveld quantitative phase *** transmission electron microscope(TEM)images and Rietveld analysis reveal almost isotropic particle size in the nano range with a very narrow size *** obtained phase percentage of PbS and PbSO4are smaller than nominated values(x)suggesting dissolving of some Pb and S ions into NCO which is then confirmed by the analysis of Fourier-transform infrared(FTIR)spectra of nanocomposite *** absorption spectra are modified upon doping NCO with *** optical band gaps of the nanocomposites increase as the amount of PbS *** effect of alloying on extinction coefficient,refractive index,dielectric constant,optical conductivity,the intensity,and emitted color from the photoluminescence of the nanocomposite samples are also *** refractive index value of NCO and NCO-PbS nanocomposite samples exhibit normal *** photoluminescent measurements reveal that the NCO-PbS nanocomposites can emit a violet *** improvement in the values of the nonlinear optical(NLO)parameters of pristine NCO at high frequencies or the nanocomposite samples at low frequencies,are made them used in NLO photonic devices.

关键词： Co_(2)O_(4)and PbS nanocomposite FTIR optical photoluminescence

A stochastic based approach for a new site classification method:application to the Algerian seismic code

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Earthquake Engineering and Engineering Vibration 2015年第4期14卷 663-681页

作者： mohamed Beneldjouzi Nasser Laouami Civil Engineering Faculty University of Sciences and Technology Houari Boumediene Earthquake Engineering Applied Research Center (CGS)

Building codes have widely considered the shear wave velocity to make a reliable subsoil seismic classification, based on the knowledge of the mechanical properties of material deposits down to bedrock. This approach has limitations because geophysical data are often very expensive to obtain. Recently, other alternatives have been proposed based on measurements of background noise and estimation of the H/V amplification curve. However, the use of this technique needs a regulatory framework before it can become a realistic site classification procedure. This paper proposes a new formulation for characterizing design sites in accordance with the Algerian seismic building code (RPA99/ver.2003), through transfer functions, by following a stochastic approach combined to a statistical study. For each soil type, the deterministic calculation of the average transfer function is performed over a wide sample of 1-D soil profiles, where the average shear wave (S-W) velocity, Vs, in soil layers is simulated using random field theory. Average transfer functions are also used to calculate average site factors and normalized acceleration response spectra to highlight the amplification potential of each site type, since frequency content of the transfer function is significantly similar to that of the H/V amplification curve. Comparison is done with the RPA99/ver.2003 and Eurocode8 (EC8) design response spectra, respectively. In the absence of geophysical data, the proposed classification approach together with micro-tremor measures can be used toward a better soil classification.

关键词： random field transfer function soil classification RPA99/ ver. 2003 EC8 site factor response spectrum

Electrical model parameters identification of radiofrequency discharge in argon through 1D3V/PIC-MC model

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Plasma Science and Technology 2018年第9期20卷 106-113页

作者： mohamed MOStaFAOUI Djilali BENYOUCEF Laboratoire Génie Electrique et Energies Renouvelables Université Hassiba Benbouali de Chlef

This work represents a contribution to the modeling of a radiofrequency（RF） discharge in argon at low pressure（from 25 to 200 mTorr）.It is started by the validation of the collision cross sections used in the particle model through a comparison between the transport coefficients calculated by these data and the measurements of the transport coefficients already exist in the literature,the particle model is also validated by a comparison between the calculated plasma density and that measured in the *** electrical model proposed in this work consists of replacing the RF discharge by a passive circuit（resistance in series with a capacitor）,where the resistance represents the plasma medium and the obstruction of the passage of the electronic current,and the capacitor represents the sheaths and the appearance of the displacement current in these *** parameters of the electrical model are obtained through particle *** electrical model presented accurately reproduces the current of the discharge,but without considering the phenomenon of *** total harmonic distortion rate follows the variation of the plasma density;its maximum value is 5.75% at 100 mTorr.

关键词： electrical model least square method particle model radiofrequency discharge static parameters identification

3D static modeling and sequence stratigraphy using well logs and seismic data:An example of Abu Roash G member in Bahga oilfield

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Energy Geoscience 2024年第3期5卷 362-377页

作者： mohamed Reda mohamed Fathy mohamed Mosaad Fahad Alshehri mohamed S.Ahmed Geology Department Faculty of ScienceAl-Azhar UniversityP.O.Box 11884Nasr CityCairoEgypt Abdullah Alrushaid Chair for Earth Science Remote Sensing Research Geology and Geophysics DepartmentCollege of ScienceKing Saud UniversityRiyadh11451Saudi Arabia

This research uses both three-dimensional(3D)modeling and geologic well control to piece back together the architectural parts of the Late Cretaceous *** goal is to figure out the sizes,directions,locations,and controls of the layers of the fluvial sandstone *** stratigraphy is essential for 3D reservoir modeling and petroleum geology understanding in the Bahga *** purpose of this work is to create a static model that shows the layers and facies distribution in the reservoir *** will use data from nine well logs and 22 seismic lines calibrated by the Abu Roash G Member reservoir core intervals to accomplish *** petrophysical study discovered three parts in the Abu Roash G Member reservoir rock:channel fill that is affected by tides,channel fill that is dominated by tides(intertidal sands),and channel top with lenticular bedded *** model's findings point to the existence of an NNW-oriented sand body,which could be a prime location to produce *** original oil in place(OOIP)is about 3,438,279 Stock tank Barrels(STB),and the oil reserve reaches up to 1,031,484(STB).Sequence stratigraphic analysis using seismic and well log information(SB)reveals that the Upper Cretaceous AR/G reservoir of the Bahga field is characterized by third-and fourth-order stratigraphic sequences,which are constrained by three maximum Flooding Surfaces(MFS)and two Sequence *** integration of the derived geological model and sequence stratigraphic results can lower future extraction risk by identifying the locations and trends of the geologic facies with the necessary petrophysical properties for the hydrocarbon accumulations.

关键词： Three-dimensional reservoir modeling Sequence stratigraphy Reservoir characterization Abu Roash reservoir Abu Gharadig Basin

Remote Monitoring of Electric Vehicle Charging Stations in Smart Campus Parking Lot

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Journal of Modern Power Systems and Clean Energy 2020年第1期8卷 124-132页

作者： mohamed A.Ahmed mohamed R.El-Sharkawy Young-Chon Kim Department of Electronic Engineering Universidad Técnica Federico Santa MaríaValparaíso 2390123Chile Department of Communications and Electronics Higher Institute of Engineering&TechnologyKing MarriottAlexandria 23713Egypt Department of Automotive and Tractor Engineering Minia UniversityEl-Minia 61111Egypt Department of Computer Engineering Chonbuk National UniversityJeonju 561-756Korea

Smart parking lots are smart places capable of supporting both parking and charging services for electric vehicles(EVs).In order to manage EV charging,the parking lot local controller(PLLC)requires data exchange with EV charging stations(EVCSs)through communication ***,data losses and communication delays are unavoidable and may significantly degrade the system *** work aims to investigate the underlying communication networks for remote monitoring of EVCSs in a smart campus parking *** communication network consists of two subnetworks:parking area network(PAN)and campus area network(CAN).PAN covers communication among EVs,charging stations and PLLC,while CAN enables dedicated communication between PLLCs and a global controller of the *** one of the major obstacles in EV system is the lack of unified communication architecture to integrate EVCS in the power grid,we develop communication models for the in-vehicle system and EVCSs based on logical node concept of IEC 61850 ***,we implement network models for EVCSs using OPNET *** communication technologies and configurations are considered in modeling and simulations,and end-toend delay is evaluated and discussed.

关键词： Communication network electric vehicle(EV) electric vehicle charging station(EVCS) IEC 61850 OPNET smart parking lot

Insights into the adsorption performance and mechanism of Cr(Ⅵ)onto porous nanocomposite prepared from gossans and modified coal interface:Steric,energetic,and thermodynamic parameters interpretations

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Chinese Journal of Chemical Engineering 2023年第9期61卷 118-128页

作者： mohamed Mobarak Saleh Qaysi mohamed Saad Ahmed Yasser F.Salama Ahmed mohamed Abbass mohamed Abd Elrahman Hamdy AAbdel-Gawwad Moaaz K.Seliem Physics Department Faculty of ScienceBeni-Suef UniversityEgypt Geology and Geophysics Department College of ScienceKing Saud University11451 RiyadhSaudi Arabia Geology Department Faculty of ScienceBeni-Suef UniversityEgypt Department of Building materials and Construction ChemistryInstitute of Civil EngineeringTechnische Universitat BerlinBerlinGermany Structural Engineering Department Faculty of EngineeringMansoura UniversityMansouraEgypt Raw Building materials and Processing Technology Research Institute Housing and Building National Research Center(HBRC)CairoEgypt Faculty of Earth Science Beni–Suef UniversityEgypt

Herein,iron oxide/hydroxides deposits(gossans)were utilized,for the first time,in the fabrication of magnetite nanoparticles(MNPs)to load modified coal(MC).The as-synthesized MNPs@MC composite was characterized via different techniques and utilized for the Cr(Ⅵ)*** studies supported by theoretical treatment were applied to offer a new overview of the Cr(Ⅵ)adsorption geometry and mechanism at 25-45℃.Experimental results suggested that the Cr(Ⅵ)uptake was mainly governed by adsorption-reduction coupled *** Langmuir model fitted well the Cr(Ⅵ)adsorption data with maximum adsorption capacities extended from 115.24 to 129.63 mg·g^(-1).Theoretical calculations indicated that Cr(Ⅵ)ions were adsorbed on the MNPs@MC following the theory of the advanced monolayer statistical *** number of ions removed per site ranged from 1.88 to1.23 suggesting the involvement of vertical geometry and multi-ionic mechanism at all *** increment of the active sites density and the adsorption capacity at saturation with improving temperature reflected an endothermic ***,the Cr(Ⅵ)adsorption was controlled by physical forces as the adsorption energies were less than 40 kJ·mol^(-1).The calculated free enthalpy,*** internal energy explained the spontaneous nature and the viability of Cr(Ⅵ)adsorption on the MNPs@MC *** results offer a new approach in utilizing the iron-rich deposits as gossans in the preparation of magnetic and low-cost adsorbents for wastewater remediation.

关键词： Coal magnetic nanoparticles Cr(Ⅵ)adsorption Statistical models Thermodynamic parameters

In vitro and in vivo evaluation of cubosomes containing 5-fluorouracil for liver targeting

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Acta Pharmaceutica Sinica B 2015年第1期5卷 79-88页

作者： mohamed Nasr mohamed K.Ghorab Ahmed Abdelazem Department of Pharmaceutics and Industrial Pharmacy Faculty of Pharmacy Helwan University Department of Pharmaceutical Chemistry Faculty of Pharmacy Helwan University

The objective of this study was to prepare cubosomal nanoparticles containing a hydrophilic anticancer drug 5-fluorouracil(5-FU) for liver targeting. Cubosomal dispersions were prepared by disrupting a cubic gel phase of monoolein and water in the presence of Poloxamer 407 as a *** loaded with 5-FU were characterized in vitro and in vivo. In vitro, 5-FU-loaded cubosomes entrapped 31.21% drug and revealed nanometer-sized particles with a narrow particle size distribution. In vitro 5-FU release from cubosomes exhibited a phase of rapid release of about half of the entrapped drug during the first hour, followed by a relatively slower drug release as compared to 5-FU solution. In vivo biodistribution experiments indicated that the cubosomal formulation significantly(Po 0.05) increased5-FU liver concentration, a value approximately 5-fold greater than that observed with a 5-FU ***, serum serological results and histopathological findings revealed greater hepatocellular damage in rats treated with cubosomal formulation. These results demonstrate the successful development of cubosomal nanoparticles containing 5-FU for liver targeting. However, further studies are required to evaluate hepatotoxicity and in vivo antitumor activity of lower doses of 5-FU cubosomal formulation in treatment of liver cancer.

关键词： 5-Fluorouracil Hydrophilic drug Cubosomes Liver targeting Hepatotoxicity

Spectrally adapted red flare tracers with superior spectral performance

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Defence Technology（防务技术） 2017年第6期13卷 406-412页

作者： Ramy Sadek mohamed Kassem mohamed Abdo Sherif Elbasuney School of Chemical Engineering Military Technical CollegeKobry ElkobaCairoEgypt

The production of bright light, with vivid color, is the primary purpose of signaling, illuminating devices,and fire control purposes. This study, reports on the development of red flame compositions with enhanced performance in terms of luminous intensity, and color quality. The light intensity and the imprint spectra of developed red flame compositions to standard NATO red tracer(R-284 NATO) were measured using digital luxmeter, and UV-Vis. spectrometer. The main giving of this study is that the light intensity of standard NATO red tracer was increased by 72%, the color quality was also improved by60%(over the red band from 650 to 780 nm). This enhanced spectral performance was achieved by means of deriving the combustion process to maximize the formation of red color emitting species in the combustion flame. Thanks to the optimum ratio of color source to color intensifier using aluminum metal fuel; this approach offered the highest intensity and color quality. Upon combustion, aluminum was found to maximize the formation SrCL(the main reactive red color emitting species) and to minimize the interfering incandescent emission resulted from MgO and SrO. Quantification of active red color emitting species in the combustion flame was conducted using chemical equilibrium thermodynamic code named ICT. The improvement in red flare performance, established the rule that the color intensifier should be in the range from 10 to 15 Wt % of the total composition.

关键词： Pyrotechnics Colored flames Tracers Luminous intensity Molecular spectroscopy

Integration of Metabolomics and Subcellular Organelle Expression Microarray to Increase Understanding the Organic Acid Changes in Post-harvest Citrus Fruit

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Journal of Integrative Plant Biology 2013年第11期55卷 1038-1053页

作者： Xiaohua Sun Andan Zhu Shuzhen Liu Ling Sheng Qiaoli ma Li Zhang Elsayed mohamed Elsayed Nishawy Yunliu Zeng Juan Xu Zhaocheng ma Yunjiang Cheng Xiuxin Deng Key Laboratory of Horticultural Plant Biology Ministry of Education Huazhong Agricultural University

Citric acid plays an important role in fresh fruit flavor and its adaptability to post-harvest storage conditions. In order to explore organic acid regulatory mechanisms in post-harvest citrus fruit, systematic biological analyses were conducted on stored Hirado Buntan Pummelo （HBP; Citrus grandis） fruits. High- performance capillary electrophoresis, subcellular organelle expression microarray, real-time quantitative reverse transcription polymerase chain reaction, gas chromatography mass spectrometry （GC-MS）, and conventional physiological and biochemical analyses were undertaken. The results showed that the concentration of organic acids in HBP underwent a regular fluctuation. GC-MS-based metabolic profiling indicated that succinic acid, ~,-aminobutyric acid （GABA）, and glutamine contents increased, but 2- oxoglutaric acid content declined, which further confirmed that the GABA shunt may have some regulatory roles in organic acid catabolism processes. In addition, the concentration of organic acids was significantly correlated with senescence-related physiological processes, such as hydrogen peroxide content as well as superoxide dismutase and peroxidase activities, which showed that organic acids could be regarded as important parameters for measuring citrus fruit post-harvest senescence processes.

关键词： Citrus gene expression metabolite organic acids post-harvest storage.