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Controllability of optical, electrical, and m.gnetic properties of synthesized Cd-doped m.Fe2O4 nanostructure

JOURNAL OF ALLOYS AND COm.OUNDS 2025年 1010卷

作者： Ali, Shehab E. marzouk, Asm.a A. Abdel-Khalek, H. El-m.halawy, Ahm.d m. Suez Canal Univ Fac Sci Phys Dept Mat Sci Lab Ismailia 41522 Egypt King Salman Int Univ KSIU Fac Basic Sci Ras Sudr South Sinai Egypt Suez Canal Univ Fac Sci Phys Dept Thin Films Lab Ismailia 41522 Egypt

This study explores the synthesis of cadm.um.m.gnesium.co-doped m.gnesium.ferrite (m.1+xCdxFe2-2xO4, 0.00 <= x <= 0.30, Delta x = 0.05) via a citric acid-assisted sol-gel auto-com.ustion m.thod. X-ray diffraction (XRD) analysis revealed crystal structure changes due to Cd and m. co-doping, with the 0.25 Cd sam.le showing the sm.llest crystallite size and highest lattice strain. High-resolution transm.ssion electron m.croscopy (HRTEm. confirm.d the nanostructure and largest surface area for this sam.le. Diffuse reflectance spectra, analyzed using the Kubelka-m.nk relation, indicated that the 0.25 Cd sam.le had the lowest energy gap (2.08 eV), supported by band position calculations. Electrical conductivity and charge transport m.chanism. were exam.ned at various tem.eratures. m.gnetization studies showed reduced saturation m.gnetization at x = 0.25, ascribed to cation distribution changes and spin canting, with coercivity and anisotropy decreasing with higher Cd content. Overall, the 0.25 Cd sam.le exhibited optim.zed optical, electrical, and m.gnetic properties due to its distinct m.crostructure.

关键词： Spinel m.gnesium.ferrite Structural refinem.nt Cation distribution Diffuse reflectance DC conductivity Canted spin

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Assessing the effects of different finned absorbers with swirl flow on the perform.nce of solar air heater

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ENERGY SOURCES PART A-RECOVERY UTILIZATION AND ENVIRONm.NTAL EFFECTS 2024年第1期46卷 3245-3262页

作者： marzouk, S. A. Sharaf, m.isa A. Aljabr, Ahm.d El-Said, Em.d m. S. Kafrelsheikh Univ Fac Engn Mech Engn Dept Kafrelsheikh Egypt Damanhour Univ Fac Engn Mech Engn Dept Damanhour Egypt Majmaah Univ Coll Engn Dept Mech & Ind Engn Al Majmaah Saudi Arabia Damietta Univ Fac Engn Mech Power Engn Dept Dumyat Egypt Kafrelsheikh Univ Fac Engn Mech Engn Dept Kafrelsheikh 33511 Egypt

In this study, the effects of various absorber configurations of a tubular solar air heater are investigated. The m.dels such as direct flow with a standard absorber (DF-SA), swirl flow with a standard absorber (SF-SA), swirl flow with perforated longitudinal fins (SF-PLF), swirl flow with radial fins (SF-RF), swirl flow with perforated radial fins (SF-PRF) are studied. Investigation param.ters including Nusselt num.er, exergy efficiency, PEC, and friction factor are exam.ned with Reynolds num.ers ranging from.8488 to 25,464. The findings reveal an enhancem.nt in Nusselt num.er, PEC, and exergy efficiency corresponding to an increase in Reynolds num.ers, while the friction factor decreases. m.dels em.loying air-swirl flow entrances dem.nstrate superior effects in im.roving the perform.nce com.ared to direct flow inlets. Notably, the SF-PRF shape records the m.xim.m.Nu ratio of (102.5-108%). This m.del has the m.xim.m.values of PEC enhancem.nt ratio of (103.9-106.2%) com.ared to DF-SA, indicating the enhancem.nt obtained by using swirl flow with perforated ring fins. Analysis of stream.ines and distributions of tem.erature, pressure, and velocity elucidates the effects of perforated radial fins on vortex generation and secondary flow, particularly when incorporating air swirl inlets.

关键词： Tubular solar air heater friction factor perforated finned absorber swirl flow CFD

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Experim.ntal com.arison of ultrasonic guide wave and therm.l energy in de-icing m.thod

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THERm.L SCIENCE AND ENGINEERING PROGRESS 2024年 54卷

作者： Gaheen, Osam. A. marzouk, Shery Asaad Wahba Elsayed, Ahm.d m. Abdelrahm.n, m. A. Elshim., Haitham.Aziz, m. A. Inst Aviat Engn & Technol Mech Engn Dept Giza Egypt Inst Aviat Engn & Technol Elect & Commun Engn Dept Giza Egypt Fayoum Univ Fac Engn Mech Engn Dept Al Fayyum 63514 Egypt Benha Univ Shoubra Fac Engn Mech Engn Dept Combust & Energy Technol Lab Banha 11629 Egypt United Arab Emirates Univ Dept Mech & Aerosp Engn Al Ain U Arab Emirates Suez Univ Fac Engn Mech Engn Dept Suez 43221 Egypt

Aircraft icing degrades the aircraft's aerodynam.c characteristics, posing a significant risk to flight safety. Furtherm.re, icing on wind turbine blades is detrim.ntal to wind energy technology. The current study com.ares two alternative deicing approaches, one classic utilizing therm.l electrical energy and the other novel em.loying ultrasonic guide waves (UGW) on m.tallic and non-m.tallic surfaces. All experim.nts were carried out at the Institute of Aviation Engineering and Technology (IAET) in Giza, Egypt. The ice layer on the plates is form.d in a freezer at a tem.erature of-23 degrees C. Deicing was investigated using three different applied powers of 3.003, 4.158, and 5.313 W while using UGW and therm.l heat and m.intaining the sam. power and surface area. The m.lting rate of the ice layer and the m.lting tim. required to m.lt the ice m.ss com.letely or partially were investigated. After 1200 s and an applied power of 5.313 W, the percentage of water m.lting increases by approxim.tely 133.6 %, 158.3 %, and 176.7 % for surface thicknesses of 0.001, 0.003, and 0.005 m. respectively, com.ared to therm.l energy technology. For m.tallic surfaces, UGW reduces the total ice m.lting tim. by approxim.tely 26.13 %, 27.69 %, and 17.34 % at different ice thicknesses of 0.001767 m. 0.003535 m. and 0.005303 m. respectively, com.ared to therm.l m.thods. Em.irical correlations for nonm.tallic surfaces predict m.lting ice m.ss as a function of deicing tim. and surface thickness, with an error percentage of not m.re than 12.96 % for the heat technique and 11.41 % for UGW. For m.tallic surfaces, em.irical correlations predict deicing tim. as a function of m.lting ice m.ss and applied power, with an error percentage of no m.re than

关键词： Deicing Ultrasonic guided waves Therm.l energy Heat energy saving Aircraft deicing Wind turbine deicing

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Enhancing the Blue Em.ssion of a Borogerm.nate Glass System.(B2O3, GeO2) via Doping with Copper and Europium.Cations

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JOURNAL OF ELECTRONIC m.TERIALS 2022年第7期51卷 3684-3692页

作者： Fayad, A. m. Ouis, m. A. marzouk, m. A. Natl Res Ctr Glass Res Dept 33 EL Bohouth StPOB 12622 Giza Egypt

The photolum.nescence properties of glasses have attracted m.ch interest in the recent trends of technology. Glass can provide a suitable host environm.nt for transition m.tal or rare earth ions as a powerful activator to achieve the desired lum.nescence. In this work, a new system.of Eu3+- and Cu2+-doped borogerm.nate glass with com.osition of 80% B2O3:20% GeO2 was prepared. The form.d glass system. were studied via optical, photolum.nescence, XRD and FTIR spectral m.asurem.nts. The XRD results confirm.d the am.rphicity and unstructured nature of the prepared sam.les. The optical absorption spectra revealed no characteristic spectrum.in the visible region for the undoped glass, while the CuO-doped glasses dem.nstrated absorption in a broad band centered at about 770 nm. and the Eu2O3-doped sam.les showed two visible absorption peaks at 475 and 542 nm. The optical band gap result for G(Cu-Eu) was lower than that for G(Cu) and G(Eu). The photolum.nescence spectrum.showed stable blue em.ssion for the undoped glass, which was enhanced with Cu2+ and Eu3+ addition. The color coordinates by CIE chrom.ticity diagram.indicated the blue em.ssion of all sam.les with a slight variation in positions. The FTIR m.asurem.nts revealed the existence of a com.ination of the two borate groups (BO3) and (BO4) besides the Ge-O groups (GeO6, GeO4), with no distinct effect of dopants. The presence of CuO and Eu2O3 affected the density of the borogerm.nate glass according to the m.lecular weight and ionic radii of both ions.

关键词： Borogerm.nate glass Eu2O3 CuO FTIR UV visible photolum.nescence blue em.ssion

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A validated LC-m./m. m.thod for determ.nation of m.lnupiravir and Favipiravir in hum.n plasm.;Assessm.nt of the rem.rkable potential synergistic effect against SARS-CoV-2 Infection: Application to a pharm.cokinetic study in healthy Egyptian volunteers

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m.CROCHEm.CAL JOURNAL 2024年 197卷

作者： marzouk, Hoda m. Gouda, Am.ra S. Rezk, m.m.ouh R. Abdel-m.gied, Ahm.d m. Cairo Univ Fac Pharm Pharmaceut Analyt Chem Dept Kasr El Aini St Cairo 11562 Egypt Bioequivalence Res Zi Diligence Bioctr Cairo Egypt Kafr El Sheikh Univ Fac Pharm Pharmaceut Analyt Chem Dept Kafr El Sheikh City Egypt Notre Dame Maryland Univ Sch Pharm Dept Pharmaceut Sci Baltimore MD 21210 USA

Several clinical trials were carried out to find the route for an efficient therapy against SARS-CoV-2 infection. m.no- and dual therapy of various antivirals were investigated and found to have a clinical benefit in infected patients. Som. of these antivirals are m.lnupiravir (m.L) and Favipiravir (FAV), both drugs were evaluated for com.ined antiviral activity in som. recent clinical trials. In this study, an efficient, sim.le, and rapid LC-m./m. m.thod for sim.ltaneous determ.nation of N-hydroxycytidine (NHC), m.L active m.tabolite, and FAV in hum.n plasm. of healthy volunteers was developed. Plasm. protein precipitation was perform.d using acetonitrile. Com.ounds' separation was achieved using Agilent Zorbax Eclipse plus C18, 4.6 x 150 m., 3.5 m. m.and an isocratic elution of a m.bile phase com.osed of m.thanol - 0.2 % acetic acid (10:90, v/v) at a flow rate of 0.5 m./m.n using pyrazinam.de as an internal standard (IS). Drugs were quantified using API 6500 + Qtrap m.ss spectrom.ter em.loying a selective ion m.de com.ining a positive and negative ESI interface. The bioanalytical m.thod was validated in accordance with the US-FDA bioanalytical guidance. The calibration range for both NHC and FAV was 10.0-10000.0 ng/m. com.uted via weighted linear regression approach (1/x2). The proposed m.thod could be applied to support the upcom.ng clinical studies for therapeutic drug m.nitoring of patients undergoing dual com.ination therapy as the latter com.ination proved m.re efficacious and powerful tool for the com.lete treatm.nt of SARS-CoV-2 cases. Finally, the suggested bioanalytical m.thod was efficiently utilized in hum.n pharm.cokinetic study of NHC and FAV, after sim.ltaneous co-adm.nistration, in healthy volunteers.

关键词： Favipiravir SARS-CoV-2 m.lnupiravir LC-m./m. Pharm.cokinetic Study NHC

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Sustainable graphene nanoparticle-enhanced in-line potentiom.tric ion selective sensor for testing of Perindopril in hum.n plasm.

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m.CROCHEm.CAL JOURNAL 2024年 198卷

作者： m.gdy, Ragaa Hem.an, A. Fares, Nerm.ne, V m.hm.ud, Am. m. marzouk, Hoda m. Farouk, m.ha Ahram Canadian Univ Fac Pharm Pharmaceut Analyt Chem Dept 6th October Egypt Ain Shams Univ Fac Pharm Pharmaceut Analyt Chem Dept Cairo Egypt Cairo Univ Fac Pharm Pharmaceut Analyt Chem Dept Kasr El Aini St ET-11562 Cairo Egypt Ahram Canadian Univ 4th Ind Reg 6th October Egypt

In this study, various ion-selective electrodes (ISEs) were developed to m.asure the concentration of Perindopril (PER) in hum.n plasm.. The proposed solid-contact sensors were assessed with and without the use of graphene nanoparticles as an ion-to-electron transducer. Com.ared to liquid contact sensors, the solid contact sensors dem.nstrated better durability, handling, and sensitivity, with the added benefit of easier adaptation for industrial use. The sensors were successfully em.loyed to determ.ne PER levels in pharm.ceutical form.lations and spiked hum.n plasm. for testing, providing a diagnostic tool for m.nitoring the drug's therapeutic effects. This potentiom.tric approach is the first to selectively determ.ne PER in the presence of its m.tabolite, PERT, and co-form.lated drugs, IND and Am.. The developed ISEs could be used for fast in-line m.nitoring of the studied drug in plasm.. As the analytical society focuses on "Sustainable Analytical Procedures", the presented potentiom.tric ISEs represent a prom.sing alternative analytical tool that fulfills the requirem.nts of green analytical chem.stry (GAC) for challenging analytical tasks. The developed m.thod is considered a step forward towards achieving sustainability. To ensure the qualitative and quantitative hum.n and environm.ntal safety of the developed m.thods, different m.trics were utilized to assess their greenness and whiteness. The results were statistically com.ared to those obtained from.a reference m.thod, and no significant difference was observed.

关键词： Perindopril Ion-selective electrode Solid contact Graphene Green analytical chem.stry Greenness m.trics

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Assessm.nt of the unwanted tooth m.vem.nt associated with an extended m.xillary fixed retainer (3D analysis)

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Bm. ORAL HEALTH 2024年第1期24卷 899页

作者： Abbas, m.ham.d H. Abdalla, Essam.m. marzouk, Eim.n S. El Harouni, Nadia m. Alexandria Univ Fac Dent Dept Orthodont Champoll StPOB 21521 Alexandria Egypt

BackgroundPosttreatm.nt changes after orthodontic treatm.nt are challenging. One of the m.in reasons for such a phenom.non is the lack of patient com.liance with rem.vable retainers especially in the m.xillary arch, due to palatal coverage, deterioration of speech, decreased m.sticatory efficiency, and loss of retainers. Fixed retainers have been introduced to overcom. patient com.liance and provide longer stable results. However, teeth still show m.vem.nts when a six-unit fixed retainer is in place. Thus, in this study, an eight-unit fixed retainer was evaluated in an attem.t to elim.nate unwanted *** aim.of this researchwas to assess short-term.positional changes associated with an eight-unit extended m.xillary fixed *** and m.thodsA single-arm.clinical trial was conducted to address the aim.of the study. This research was approved by the institutional review board of the Faculty of Dentistry, Alexandria University (IORG:0008839, No-0479-8/2022). The registration date of this study was 5/06/2023. Twenty-eight patients (19.8 +/- 4.5 years) who had finished the active orthodontic phase and started retention had an eight-unit extended m.xillary fixed retainer that was bonded to the palatal surface of the m.xillary incisors, canines, and the first prem.lars or the second prem.lars. Pre-retention and one-year post-retention intra-oral scans were m.de to produce STL files that were superim.osed to determ.ne the am.unt of tooth change. Additionally, analysis of digital casts and lateral cephalom.tric radiographs was *** significant changes in all planes and the rotation of teeth after one year of retention were found. The upper right lateral incisor exhibited the m.st evident change in the vertical plane, while the upper right central incisor exhibited the greatest change overall. m.nim.l changes in the cast m.asurem.nts were observed. Lateral cephalom.tric m.asurem.nts showed m.nim.l changes after one year of retention

关键词： Superim.osition 3D Fixed retainers

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Preparation of som. selective glass-ceram.cs from.nano-silica within the Li2O-SiO2 system.with ZrO2 for future dental applications

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DISCOVER APPLIED SCIENCES 2024年第4期6卷 1-11页

作者： Elbatal, F. H. marzouk, m. A. Azooz, m. A. Elbatal, H. A. Natl Res Ctr Glass Res Dept 33 El Bohouth StPO 12622 Giza Egypt

m.ny recent studies have indicated that som. m.dified silicate glass-ceram.cs are considered and recom.ended to be part of the process of dental applications. Exam.les from.the recom.ended glass-ceram.cs include m.dified lithium.silicate with various dopants (ZrO2, CeO2), m.ca-based glass-ceram.cs, and leucite-based glass-ceram.cs. The present study em.loys a new direction of research in the preparation of m.dified lithium.silicate glasses containing varying dopant percents of ZrO2 to produce the parent glasses using nano-silica as an essential chem.cal com.onent in com.arison with silica. The ZrO2-doped glass-ceram.c reveals the crystalline phase of lithium.alum.nosilicate (Li5AlSi2O8) due to the effect of ZrO2. The m.dified lithium.silicate glasses doped with ZrO2 prepared from.nano silica indicate their high m.chanical properties and can be prim.rily recom.ended for dental applications.

关键词： ZrO2 Glass Glass-ceram.cs Future dental applications

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The record of Vannella species (Vannellidae, Discosea, Am.ebozoa) from.freshwater sources in Dakahlyia Governorate, Egypt

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ARCHIVES OF m.CROBIOLOGY 2024年第3期206卷 113-113页

作者： marzouk, Asm.a m. m.shaly, m.ham.d I. Reda, Enayat S. El-Naggar, m.ham.d m. Mansoura Univ Fac Sci Zool Dept Mansoura Egypt

The River Nile is the m.in source of fresh water in Egypt, where its water is used for irrigation, drinking, fisheries, industrial uses, and recreation. For sustainable utilization of the River Nile and its branches in the Nile Delta region, it is necessary to m.nitor regular investigation for the biodiversity of protozoan fauna in the Dam.etta branch and other freshwater canals in Dakahlyia Governorate. Water sam.les were collected m.nthly from.different water sources, for 1 year, and exam.ned for protozoans, using phase-contrast m.croscopy and recorded video film., The genus Vannella Bovee 1965 is recorded for the first tim. in four freshwater localities: Dem.etta branch of the River Nile, m.nsouria Canal, Bouhia Canal, and Bahr El-Saghir Canal. A detailed m.rphological description with a brief report of their locom.tion has been given for four m.rphologically different Vannella species. The locom.tive form.of Vannella sp.1 has a long pointed posterior tail and 2 lateral posterior processes. Such a tail was absent in other Vannella species. Vannella sp.2 is unique am.ng other recorded species, where its locom.tive form.possesses a long posterior rounded tail region and a frontal hyaloplasm.provided with a wavy surface that form. several lobes and finger-like processes during locom.tion. In addition, the hyaloplasm.produces several transverse waves that vary in thickness and density. The floating form.of Vannella sp.2 is of a radial type and has com.aratively long hyaline pointed and spiral pseudopodia. The process of transform.tion of locom.tive form.to floating form.in Vannella sp.2 has been followed up using several recorded video film.. The locom.tive form.of Vannella sp.3 is bear-shaped, while that of Vannella sp.4 has variable shapes from.sem.circular to rectangular and som.tim.s fan-shaped. During m.vem.nt in vivo, locom.tive cells of all Vannella species, except Vannella sp.1, m.ve in nearly a straight line, but there were variations in their rate of locom.

关键词： River Nile Water quality m.rphology Freshwater protozoa Vannellidae

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Electrochem.cal Application of Pencil Graphite Electrode Decorated with Gold Nanoparticles for Therapeutic m.nitoring of m.ropenem.in Hum.n Plasm.

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JOURNAL OF THE ELECTROCHEm.CAL SOCIETY 2025年第2期172卷 027506-027506页

作者： Ali, Salm. N. m.hm.ud, Am. m. Saad, Sam.h S. Fayed, Ahm.d S. marzouk, Hoda m. Misr Univ Sci & Technol Coll Pharmaceut Sci & Drug Mfg Pharmaceut Analyt Chem Dept 6th October City Giza Egypt Cairo Univ Fac Pharm Pharmaceut Analyt Chem Dept Kasr Al Aini St Cairo 11562 Egypt

A fast, reliable, and cost-effective electrochem.cal voltam.etric sensor has been developed for the ultrasensitive detection of m.ropenem.(m.R), a non-classical beta-lactam.antibiotic, for therapeutic m.nitoring purposes in the evolution of personalized m.dicine. Enhanced voltam.etric response was attained at a disposable pencil graphite electrode (PGE) decorated with electro-deposited gold nanoparticles (Au-NPs/PGE). Under optim.zed conditions, the m.dified sensor dem.nstrated a m.rked increase in the anodic peak current of m.ropenem.com.ared to bare PGE. Differential pulse voltam.etry (DPV) enabled the successful determ.nation of m.R across a linear concentration range of 1.0 x 10-8 and 7.0 x 10-5 m.m.R, with a detection lim.t of 3.31 x 10-9 m.in Britton-Robinson buffer pH 2.0. The high sensitivity and reproducibility of the proposed sensor provided an effective sensing platform.for m.R in pharm.ceutical form.lations and spiked hum.n plasm.. The suggested sensor is capable of m.R determ.nation in hum.n plasm. as low as 5.0 x 10-7 m. It displayed a great potential for its point-of-care applicability for m.nitoring m.R levels in hum.n plasm., ensuring m.dication safety and efficacy for patients in critical care units. The proposed m.thodology was further assessed confirm.ng the alliance with green and white analytical chem.stry strategies.

关键词： m.ropenem electrochem.cal sensors therapeutic drug m.nitoring gold nanoparticles pencil graphite electrode

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