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Phase Characterizations and Photocatalytic Applications of CuO-K_2mo_4O_(13) Composites

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Acta metallurgica Sinica(English Letters) 2014年第1期27卷 180-184页

作者： m.kassem Chemistry Department Atomic Energy Commission of Syria

A series of CuO-K2mo4013 composite materials have been prepared by mixing appropriates quantities, in solid state, of CuO and pure K2mo4013 according to the molar ratios CuO/K2mo4013 = 0.05, 0.1, 0.2, 0.5, and 1. The prepared samples were characterized using techniques such as X-ray diffraction （XRD）, Fourier transform infrared spectroscopy （FT-IR）, differential thermal analysis （DTA）, nitrogen adsorption measurements, and UV spectroscopy. According to XRD results, the phase composition of the CuO-Kemo4013 systems has significantly changed by increasing the molar ratio CuO/ K2mo4013 where new phases, identified as K2mo3Olo and CumoO4, have been detected. The formation of these new phases has been tracked through FT-IR and DTA measurements. The nitrogen adsorption-desorption measurements also reveal a change in the pore type of the studied materials due to the presence of these new phases. The photocatalytic activities of K2m04OI3 and CuO-K2mo4013 composites were studied by means of monitoring the ability of these materials to the degradation, under UV irradiation, of methyl red in liquid media. It was found that the phase composition of the used samples significantly controls their photocatalytic activities.

关键词： Potassium tetramolybdate Copper oxide Composite Photocatalyst

Structural Analysis for Qazzaz metamorphic Core Complex,Northwestern Arabian Shield,Saudi Arabia

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Acta Geologica Sinica(English Edition) 2024年第5期98卷 1187-1201页

作者： mansour H.AL-HASHIm osama m.K.kassem Department of Geology and Geophysics College of ScienceKing Saud University11451 RiyadhSaudi Arabia Department of Geology National Research CenterCairoEgypt

Identifying deformational mechanisms and associated structures at various scales,ranging from regional-scale structures to microscopic fabric,is crucial for the assessment of tectonic ***-three samples were taken from the Qazzaz metamorphic core complex to estimate the finite strain for felsic and mafic *** samples included gneisses rocks,monzogranite,and metavolcano-sedimentary rocks for both the Thalbah and Bayda *** the Rf/j and Fry methods,the axial ratios(XZ)range about 2.20 to 7.10 and 1.90 to 9.10,*** various rock units,the strain measurements show moderate to highly *** of the observed samples show shallow WNW dipping along a N to WNW trend of finite strain(X).The short axes(Z)based to be subvertical foliation related with a subhorizontal *** results demonstrate that contacts generated at semi-brittle to ductile deformation and that the strain of magnitude has the same value for different lithologic *** concluded that nappe generation in orogens results from pure shear deformation.

关键词： Finite strain metamorphic core complex Qazzaz area Saudi Arabia

Intelligent Fractional-Order Controller for SmES Systems in Renewable Energy-Based microgrid

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Computer modeling in Engineering & Sciences 2024年第8期140卷 1807-1830页

作者： Aadel m.Alatwi Abualkasim Bakeer Sherif A.Zaid Ibrahem E.Atawi Hani Albalawi Ahmed m.kassem Electrical Engineering Department Faculty of EngineeringUniversity of TabukTabuk47913Saudi Arabia Industrial Innovation and Robotic Center(IIRC) University of TabukTabuk47731Saudi Arabia Department of Electrical Engineering Faculty of EngineeringAswan UniversityAswan81542Egypt Renewable Energy and Environmental Technology Centre University of TabukTabuk47913Saudi Arabia Electrical Engineering Department Faculty of EngineeringSohag UniversitySohag82524Egypt

An autonomous microgrid that runs on renewable energy sources is presented in this *** has a supercon-ducting magnetic energy storage(SmES)device,wind energy-producing devices,and an energy storage ***,because such microgrids are nonlinear and the energy they create varies with time,controlling and managing the energy inside them is a difficult ***-order proportional integral(FOPI)controller is recommended for the current research to enhance a standalone microgrid’s energy management and *** suggested dedicated control for the SmES comprises two loops:the outer loop,which uses the FOPI to regulate the DC-link voltage,and the inner loop,responsible for regulating the SmES current,is constructed using the intelligent FOPI(iFOPI).The FOPI+iFOPI parameters are best developed using the dandelion optimizer(DO)approach to achieve the optimum *** suggested FOPI+iFOPI controller’s performance is contrasted with a conventional PI controller for variations in wind speed and microgrid *** optimal FOPI+iFOPI controller manages the voltage and frequency of the *** behavior of the microgrid as a reaction to step changes in load and wind speed was measured using the proposed *** simulations were used to evaluate the recommended system’s *** results of the simulations showed that throughout all interruptions,the recommended microgrid provided the load with AC power with a constant amplitude and *** addition,the required load demand was accurately ***,the microgrid functioned incredibly well despite SmES and varying wind *** obtained under identical conditions were compared with and without the best FOPI+iFOPI *** utilizing the optimal FOPI+iFOPI controller with SmES,it was found that the microgrid performed better than the microgrid without SmES.

关键词： Fractional-order proportional integral(FOPI) intelligent controller renewable energy resources superconducting magnetic energy storage optimization

New Antenna Array Beamforming Techniques Based on Hybrid Convolution/Genetic Algorithm for 5G and Beyond Communications

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Computer modeling in Engineering & Sciences 2024年第3期138卷 2749-2767页

作者： Shimaa m.Amer Ashraf A.m.Khalaf Amr H.Hussein Salman A.Alqahtani mostafa H.Dahshan Hossam m.kassem Electronics and Communications Engineering Department Higher Institute of Engineering and TechnologyKafr ElsheikhEgypt Electronics and Electrical Communications Engineering Department Faculty of EngineeringMinia UniversityMiniaEgypt Electronics and Electrical Communications Engineering Department Faculty of EngineeringTanta UniversityTantaEgypt Electronics and Electrical Communications Engineering Department Faculty of EngineeringHorus University EgyptNew DamiettaEgypt Department of Computer Engineering College of computer and Information SciencesKing Saud UniversityRiyadh11543Saudi Arabia School of Computing Mathematics and EngineeringCharles Sturt UniversityBathurstNSW2795Australia

Side lobe level reduction(SLL)of antenna arrays significantly enhances the signal-to-interference ratio and improves the quality of service(QOS)in recent and future wireless communication systems starting from 5G up to ***,it improves the array gain and directivity,increasing the detection range and angular resolution of radar *** study proposes two highly efficient SLL reduction *** techniques are based on the hybridization between either the single convolution or the double convolution algorithms and the genetic algorithm(GA)to develop the Conv/GA andDConv/GA,*** convolution process determines the element’s excitations while the GA optimizes the element *** m elements linear antenna array(LAA),the convolution of the excitation coefficients vector by itself provides a new vector of excitations of length N=(2m−1).This new vector is divided into three different sets of excitations including the odd excitations,even excitations,and middle excitations of lengths m,m−1,andm,*** the same element spacing as the original LAA is used,it is noticed that the odd and even excitations provide a much lower SLL than that of the LAA but with amuch wider half-power beamwidth(HPBW).While the middle excitations give the same HPBWas the original LAA with a relatively higher *** the increased HPBWof the odd and even excitations,the element spacing is optimized using the ***,the synthesized arrays have the same HPBW as the original LAA with a two-fold reduction in the ***,for extreme SLL reduction,the DConv/GA is *** this technique,the same procedure of the aforementioned Conv/GA technique is performed on the resultant even and odd excitation *** provides a relatively wider HPBWthan the original LAA with about quad-fold reduction in the SLL.

关键词： Array synthesis convolution process genetic algorithm(GA) half power beamwidth(HPBW) linear antenna array(LAA) side lobe level(SLL) quality of service(QOS)

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

Effects of Bentonite,Hydrogel and Biochar Amendments on Soil Hydraulic Properties from Saturation to Oven Dryness

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Pedosphere 2019年第5期29卷 598-607页

作者： osama m0HAWESH Wolfgang DURNER Department of Plant Production Faculty of AgricultureMutah UniversityKarak 61710 (Jordan) Division of Environmental Science and Technology Graduate School of AgricultureKyoto UniversityKyoto 6110011 (Japan) Institute of Geoecology Technical University of BraunschweigLanger Kamp 19cBraunschweig 38106 (Germany)

Effects of hydrogel, bentonite, and biochar as soil amendments on soil hydraulic properties and improving water availability from saturation to oven dryness were investigated. Soils were mixed with hydrogel (0.10%, 0.25%, and 0.50%), bentonite (0.5%, 1.0%, and 2.5%), and biochar (1.0%, 2.5%, and 5.0%) as soil amendments (weight:weight). Three methods (extended multistep outflow (XmSO), evaporation (EVA), and WP4 dewpoint potentiometer) were used to measure soil hydraulic properties from saturation to oven dryness. The cumulative XmSO results were more uniform across all the applied pressure steps for the amended soils. The EVA exhibited a shorter linear decrease during the first evaporation stage and a lower evaporation rate during the second evaporation stage. The WP4 results also exhibited that soil amendments increased the soil water content of the amended soils at low matric potentials. The results of soil water retention curves revealed that the unamended soil retained less water at any matric potential compared to the amended soils. Soil hydraulic conductivity decreased with increasing amount of soil amendments. The saturated hydraulic conductivity was higher for the unamended soil than the soils amended w计h 2.5% bentonite, 0.50% hydrogel, and 5.0% biochar by 11, 3, and 18 times, respectively. These results suggested that soil amendments improved soil water retentivity, which confirmed the appropriateness of these soil amendments for potential use in sandy soil improvements. However, field experiments and economical perception studies should be considered for further investigation.

关键词： evaporation extended multistep outflow soil amendment soil matric potential soil moisture soil water retentivity water availability WP4 dewpoint potentiometer

Effects of vegetable oil residue after soil extraction on physical-chemical properties of sandy soil and plant growth

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Journal of Environmental Sciences 2008年第12期20卷 1458-1462页

作者： GONG Zongqiang LI Peijun B. m. Wilke kassem Alef Instirute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Institute of Ecology Berlin University of Technology Berlin 10587 Germany

Vegetable oil has the ability to extract polycyclic aromatic hydrocarbons(PAHs)from contaminated sandy soil for a remediation purpose,with some of the oil remaining in the *** most of the PAHs were removed,the risk of residue oil in the soil was not *** objective of this study was to evaluate the effects of the vegetable oil residue on higher plant growth and sandy soil properties after soil extraction for a better understanding of the soil *** of sunflower oil and column ex...

关键词： soil vegetable oil plant growth organic carbon pH

Numerical damage evaluation of perforated steel columns subjected to blast loading

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Defence Technology（防务技术） 2022年第5期18卷 735-746页

作者： mahmoud T.Nawar Ibrahim T.Arafa osama m.Elhosseiny Structural Engineering Department Zagazig UniversityZagazig44519Egypt

The structural performance of perforated steel columns(PSCs)is significantly more complex than the one of solid web I-shaped elements under the diversity of blast loading *** damage criterion of PSCs is not only related to initial deformation response during the blast but also the residual axial load capacity and it can be considered as a reliable index after the blast ***,the PSCs damages will be studied in two stages;direct and post blast *** the present study,the dynamic response of PSCs was numerically evaluated under different levels of blast threats using LS-DYNA *** explicit finite element(FE)analyses are carried out to investigate the effect of various parameters,such as web opening shapes,boundary conditions and strengthening details on the damage index and toughness of the PSCs compared to the parent steel *** results of the comparative study show that the damage and toughness decrease when the support condition changes from pinned to fixed ends through the two stages of *** give high toughness compared to its parent sections during blast shock stage while,a remarkable decrease in toughness is observed during the application of axial gravity after blast ***,the web opening shapes have slight effects on the global dynamic behavior of PSCs,particularly in terms of residual *** the contrary,the retrofitting strategy using both closed holes at end and vertical stiffeners have an effective enhancement to get higher toughness in case of the extreme blasts.

关键词： Perforated steel columns Blast load Damage criterion Numerical modeling Explicit finite element analysis Web-opening shapes

Pharmacist-managed Anticoagulation Services for Warfarin management in Tertiary Hospitals:The Egyptian Experience

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Journal of Clinical and Nursing Research 2022年第3期6卷 24-30页

作者： Amira B kassem Asmaa m Farrag Dina Shafea osama mohamed Ibrahim Department of Clinical Pharmacy and Pharmacy Practice Faculty of Pharmacy Damanhour University Egypt Abo-Kir General Hospital Ministry of HealthAlexandriaEgypt Department of Pharmacy Practice and Pharmacotherapeutics Faculty of PharmacyUniversity of SharjahUAE Department of Clinical Pharmacy Faculty of PharmacyCairo University Egypt

Background:Warfarin is widely regarded as the main anticoagulant in lowering the risk of *** study used indicators to compare pharmacist-managed anticoagulation services,using a well-prepared protocol,with physician-managed anticoagulation services・methods:A retrospective prospective pilot study was conducted to compare patient outcomes before and after transitioning patients to phannacist-managed anticoagulation services,comparing the proportion of those with therapeutic international normalized ratio(INK),subtherapeutic INK,and supratherapeutic INR,as well as their bleeding occurrences as indicators of assuring quality ***:A significant improvement in anticoagulation management was noted in the transition to pharmacist-managed anticoagulation *** proportion of those with subtherapeutic INR decreased from 61.8%to 11.8%(pm 20.6%to 2.9%(pm 17.6%to 85.3%(pm 11.8%to 0.0%,without significant difference in warfarin doses(median from 4 before the transition to 5 after);in addition,the time to reach therapeutic INR decreased from 12-24 weeks to 2-8 weeks after transitioning to pharmacist-managed anticoagulation ***:Pharmacist-managed anticoagulation services are considered safer and more effective than physician-managed anticoagulation services alone in terms of patientsJ adherence and satisfaction,which provide an excellent opportunity for quality assurance care.

关键词： Pharmacist-managed anticoagulation services Warfarin Anticoagulation clinic Therapeutic drug monitoring