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Model Predictive Current Control for Low-Cost Shunt Active Power Filter

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1589-1598页

作者： Ali a.abdel-Aziz Mohamed A.Elgenedy Barry W.Williams the Electronic and Electrical Engineering Department Strathclyde UniversityGlasgowG11XQUK School of Computing Engineering and the Built Environment(SCEBE)Glasgow Caledonian UniversityGlasgowG40BAUK

Performance of a three-phase shunt active power filter(SAPF)relies on the capability of the controller to track the reference ***,designing an accurate current controller is crucial to guarantee satisfactory SAPF *** paper presents a model predictive current controller(MPCC)for a low-cost,four-switch,shunt active power filter for power quality improvement.A four-switch,B4,converter topology is adopted as an SAPF,hence offering a simple,robust,and low-cost *** addition,to further reduce overall cost,only two interfacing filter inductors,instead of three,are used to eliminate switching current *** proposed SAPF model MPCC is detailed for implementation,where simulation and experimental results validate effectiveness of the proposed control algorithm showing a 20%improvement in total harmonic distortion compared with a conventional hysteresis band current controller.

关键词： Four-switch converter harmonic distortion model predictive current control power quality shunt active power filter

Electrochemical anodization of cast titanium alloys in oxalic acid for biomedical applications

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Frontiers of Chemical Science and Engineering 2024年第1期18卷 13-24页

作者： Engie M.Safwat Soha a.abdel-Gawad Madiha A.Shoeib Shimaa El-Hadad Restorative and Dental Materials Department National Research CentreGiza 12622Egypt Chemistry Department Faculty of ScienceCairo UniversityGiza 12613Egypt Central Metallurgical Research and Development Institute Helwan 11421Egypt

Titanium and its alloys have numerous biomedical applications thanks to the composition and morphology of their oxide *** this study,the colorful oxide films were formed by anodizing cast Ti-6Al-4V and Ti-6Al-7Nb alloys in a 10%oxalic acid solution for 30 s at different voltages(20–80 V)of a direct current power *** force microscopy was used as an accurate tool to measure the surface roughness of thin films on the nanometer *** electron microscopy and X-ray diffraction were performed to analyze surface morphology and phase *** to the results,the produced titanium oxide layer showed high surface roughness,which increased with increasing anodizing *** impact of anodizing voltages on the color and roughness of anodized layers was *** corrosion resistance of the anodized samples was studied in simulated body fluid at pH 7.4 and a temperature of 37℃ utilizing electrochemical impedance spectroscopy and the potentiodynamic polarization *** anodized samples for both alloys at 40 V were at the optimal voltage,leading to a TiO_(2) layer formation with the best compromise between oxide thickness and corrosion ***,findings showed that TiO_(2) films produced on Ti-6Al-7Nb alloys had superior surface roughness properties compared to those of Ti-6Al-4V alloys,making them more appropriate for orthopedic *** the obtained data and the fruitful discussion,it was found that the utilized procedure is simple,low-cost,and ***,anodization in 10%oxalic acid proved a viable alternative for the surface finishing of titanium alloys for biomedical applications.

关键词： DC anodization Ti-6Al-4V alloy Ti-6Al-7Nballoy oxidefilm corrosion

Influence of anodization conditions on deposition of Hydroxyapatite on α/β Ti alloys for Osseointegration: Atomic Force Microscopy Analysis

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Transactions of Nonferrous Metals Society of China 2024年

作者： Rania E.Hammam Engie M.Safwat Soha a.abdel-Gawad Madiha Shoeib Shimaa El-Hadad Faculty of Engineering， Modern University for Technology and Information (MTI) Restorative and Dental Materials Department， National Research Centre Giza Chemistry Department， Faculty of Science， Cairo University Central Metallurgical Research and Development Institute P.O.87

Integrating titanium-based implants with the surrounding bone tissue remains challenging. This study aims to explore the impact of different anodization voltages （20-80V） on the surface topography of two-phase （α/β） Ti alloys and to produce TiO2films with enhanced bone formation abilities. Scanning electron microscopy coupled with energy dispersive spectroscopy （SEM-EDS） and atomic force microscopy （AFM） were applied to investigate the morphological， chemical， and surface topography of the prepared alloys and to confirm the growth of hydroxyapatite （HA） on their surfaces. Results disclosed that the surface roughness of TiO2films formed on Ti-6Al-7Nb alloys was superior to that of Ti–6Al–4V alloys. Ti-6Al-7Nb alloy anodized at 80 V had the highest yields of HA after immersion in SBF with enhanced HA surface coverage. The developed HA layer had a mean thickness of 128.38 ± 18.13 μm， suggesting its potential use as an orthopedic implantable material due to its promising bone integration and， hence， remarkable stability inside the human body.

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Calculation of ship motions in steep waves with restoring and Froude-Krylov forces on an adaptive panel mesh with Gauss and analytic integration methods

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Journal of Hydrodynamics 2024年第2期36卷 275-289页

作者： Malwin Wermbter Moustafa.abdel-Maksoud Institute for Fluid Dynamics and Ship Theory Hamburg University of TechnologyHamburgGermany

The impulse response method is a frequently used method to calculate ship seakeeping *** this paper,the restoring and Froude-Krylov calculation is conducted with constant evaluation of panel pressures as well as Gauss quadrature and an analytical *** applied panel grid is coarsened by an adaptive algorithm which is based on a normal vector *** comparison of methods is based on grid convergence studies which are followed by a verification of forces with computational fluid dynamics(CFD)results on the fixed duisburg test case in *** with experimental results in head,oblique and following waves show that all integration methods are *** exact integration is numerically sensitive in some *** quadrature is highly accurate;however,the additional effort is not beneficial since the geometrical accuracy has-stronger influence on the force amplitudes than the integration *** grid coarsening reduces the simulation time and is accurate up to a level,where the panel length comes close the *** added resistance at the investigated Froude number of 0.05 shows higher uncertainty levels,this applies to the results of both the numerical methods and model tests.

关键词： Ship hydrodynamics seakeeping impulse response method added resistance wave loads

Modulation of oxidative damage and genotoxicity of biosynthesized zinc oxide nanoparticles via supplementation with modified cinnamaldehyde-loaded chitosan nanoparticles in mice

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Food Science and Human Wellness 2024年

作者： Mosaad a.abdel-Wahhab Aziza A.El-Nekeety Asmaa S.Salman Zeinab K.Hamza Engy M.Akl Soher E.Aly Wenyi Kang Department of Food Toxicology & Contaminants， National Research Centre Dokki， Cairo， Egypt Genetic and Cytology Department， National Research Centre Dokki， Cairo， Egypt Department of Fats and Oils， National Research Centre Dokki， Cairo， Egypt National R & D Center for Edible Fungus Processing Technology， Henan University Joint International Research Laboratory of Food & Medicine Resource Function Functional Food Engineering Technology Research Center Henan

Synthesis of zinc oxide nanoparticles (Zn-NPs) via green method is an outstanding alternative to conventional/regular methods; however， the safety or toxicity of the biosynthesized ZnO-NPs in vivo is not fully explored. This study was conducted to evaluate the protective efficiency of cinnamaldehyde-loaded chitosan nanoparticles (Cin@CSNPs) against oxidative damage and genotoxicity of zinc oxide nanoparticles (ZnO-NPs) in mice. ZnO-NPs were biosynthesized using the extract of fresh leaves of Mentha pulegium L. Cin was extracted from cinnamon essential oil， and was loaded into chitosan nanoparticle (Cin@CSNPs). Both ZnO-NPs， Cin@CSNPs and CSNPs were characterized. The in vitro release of Cin@CSNPs was determined. In the biological study， 6 groups of male Balb/c mice were treated by gavage for 3 weeks as follows， control group， the group received ZnO-NPs (25 mg/kg b.w)， the groups received Cin@CSNPs at low dose (50 mg/kg b.w) or high dose (100 mg/kg b.w)， and the groups received ZnO-NPs plus Cin@CSNPs at the two tested doses. Blood and tissue samples were collected for different biochemical， genetical and histological studies. The particle size of ZnO-NPs， CSNPs， and Cin@CSNPs were (20.78 ± 2.6)， (170.0 ± 3.7)， and (218.23 ± 2.9) nm， and ξ-potential were (32.7 ± 4.6)， (8.32 ± 0.27) and (4.8 ± 0.21)， respectively. ZnO-NPs disturbed the biochemical and oxidative stress indices， AFP， CEA， TNF-α， chromosomal aberrations in somatic and germ cells， and sperm abnormality along with severe pathological changes in the hepatic， renal， and testicular tissues. Cin@CSNPs improved significantly all the parameters tested and the histological picture in a dose-dependent. Therefore， the biosynthesized ZnO-NPs exhibit oxidative damage and genotoxicity， and Cin@CSNPs have potential protective effects against the risks of ZnO-NPs and may be a promising tool to overcome the challenges of using Cin in food and pharmaceuticals applications.

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An extensive analytical and numerical study of the generalized q-deformed Sinh-Gordon equation

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Journal of Ocean Engineering and Science 2024年第3期9卷 232-239页

作者： Khalid K.Ali abdel-Haleem abdel-Aty Mathematics Department Faculty of ScienceAl-Azhar UniversityNasr-CityCairoEgypt Department of Physics College of SciencesUniversity of BishaPO Box 344Bisha 61922Saudi Arabia Physics Department Faculty of ScienceAl-Azhar UniversityAssiut 71524Egypt

In this paper,the q-deformed Sinh-Gordon equation is solved analytically using a new general form based on the extended tanh *** numerical solutions of the equation is obtained using a b-spline finite element ***,we present numerous figures to demonstrate the various solitons propagation *** type of equation has not been previously dealt with in such ways,whether analytical or *** study is very useful in studying several physical systems that have lost their symmetry.

关键词： q-Deformed equation Solitos solutions The extended tanh method Finite element method q-Calculus

Ultralong hydroxyapatite-based forward osmosis membrane for freshwater generation

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Frontiers of Chemical Science and Engineering 2024年第9期18卷 37-49页

作者： Mohamed Gamal Gomaa Hamdy Maamoun abdel-Ghafar Francesco Galiano Francesca Russo Alberto Figoli El-Sayed Ali abdel-Aal abdel-Hakim Taha Kandil Bahaa Ahmed Salah Central Metallurgical Research and Development Institute(CMRDI) 11421 CairoEgypt Chemistry Department Faculty of ScienceHelwan University11795 CairoEgypt Institute on Membrane Technology(CNR-ITM) 87036 RendeItaly

Increasing global water shortages are accelerating the pace of membrane manufacturing,which generates many environmentally harmful *** challenges need a radical rethink of developing innovative membranes that can address freshwater production without generating environmentally harmful *** work utilized the synthesized ultra-long hydroxyapatite(UHA)by the solvothermal method using the green solvent oleic acid in preparing UHA-based forward osmosis *** membranes were developed using different loading ratios of graphene oxide(GO)by vacuum-assisted filtration *** prepared GO/UHA membranes were identified using X-ray diffraction,scanning electron microscope,Fourier-transform infrared spectroscopy,and X-ray photoelectron *** contact angle and pore size distribution were determined for the obtained GO/UHA *** obtained hierarchical porous structure in the prepared membranes with interconnected channels results in a stable water flux with reverse salt *** best water flux rate of 42±2 L·m^(–2)·h^(–1)was achieved using the 50 mg GO/UHA membrane,which is 3.3 times higher than the pristine membrane,and a reverse salt flux of 67 g·m^(-2)·h^(–1).The obtained results showed a promising capability of a new generation of sustainable inorganic-based membranes that can be utilized in freshwater generation by energy-efficient techniques such as forward osmosis.

关键词： forward osmosis ultra-long hydroxyapatite graphene oxide inorganic-based membrane

Geochemistry of island arc assemblage in the Eastern Desert of Egypt and the role of Pan-African magmatism in crustal growth of the Arabian–Nubian Shield:A review

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Acta Geochimica 2024年第3期43卷 588-622页

作者： abdel-Aal Mabdel-Karim Mohamed MHamdy Adel A.Surour Geology Department Faculty of ScienceZagazig UniversityZagazig 44519Egypt Geology Department Faculty of ScienceTanta UniversityTanta 31527Egypt Department of Geological Sciences Faculty of ScienceNew Galala City 43511Egypt Geology Department Faculty of ScienceCairo UniversityGiza 12613Egypt

Neoproterozoic island arc assemblage of the Arabian–Nubian Shield(ANS)in the Eastern Desert(ED)of Egypt comprises juvenile suites of metavolcanics(MV),large amounts of meta-sedimentary rocks(MS),and voluminous metagabbros-diorites(MGD)and syn-tectonic intrusions of older granitoids(OG).We report here the updates of these four rock units in terms of classification,distribution,chemical characteristics,geodynamic evolution,metamorphism,and *** addition,we discuss these integrated data to elucidate a reasonable and reliable model for crustal evolution in the *** main features of these rock units indicate their relation to each other and the geodynamic environment dominated by early immature oceanic island arcs to primitive continental *** information of the island arc metavolcanic and plutonic rocks(gabbros,diorites,tonalites,and granodiorites)furnish evidence of the genetic *** include proximity and a coeval nature in the field;all protolith magmas are subalkaline in nature following calc-alkaline series with minor tholeiitic affinities;common geochemical signature of the arc rocks and subduction-related magmatism;their similar enrichment in LREEs;and similar major element compositions with mafic melts derived from metasomatized mantle *** volcano-sedimentary and the OG rocks underwent multiphase deformation events whereas the MGD complexes deformed *** on the magmatic,sedimentological,and metamorphic evolutions constrained by geochronological data as well as the progressive evolutionary trend from extensional to compressional regimes,a possible gradual decrease in the subducted slab dip angle is the most infl uential in any geodynamic model for arc assemblage in the ED of Egypt.

关键词： Island arc assemblage Magmatism Crustal growth Neoproterozoic Arabian–Nubian Shield Eastern Desert Egypt

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Entrepreneurship training:its influences on innovation potentials among nursing students

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Frontiers of Nursing 2024年第1期11卷 85-98页

作者： Asmaa.abdel Rahman abdel Rahman Dalia Abdallah abdelatief Medical Surgical Nursing Department Faculty of NursingAin Shams UniversityCairoEgypt

Objective:To evaluate the influences of entrepreneurship training on the innovation potential among nursing ***:A quasi-experimental design was utilized to conduct this *** study was conducted in the classroom at the faculty of nursing,and the“i Hub”center at Ain Shams University(ASU)in Cairo,Egypt.A purposive sample of 42 nursing students who participated in the“Ain Shams University-innovate”competition from the Faculty of Nursing of ASU were included in this *** collection tools included(1)Nursing students'innovation skills assessment questionnaire and(2)Innovative projects evaluation ***:There was a statistically significant difference between the mean scores of nursing students'total innovation skills pre-and post-implementation of entrepreneurship training,where P-value<***:The results of the current study support the research hypothesis because the implementation of entrepreneurship training positively affects nursing students'innovation *** entrepreneurship education in nursing and integrating it into nursing programs will stimulate creativity,innovation,and entrepreneurship among nursing students and health care services.

关键词： entrepreneurship training innovation potentials nursing students creative skills energy/motivation

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