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Preparation and characterization of glasses from.the binary sodium.fluoroborate system.NaF-B2O3 within the range (10-50 m.l% NaF) assessed by structural FTIR, optical and therm.l properties and effects of gam.a irradiation

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JOURNAL OF m.LECULAR STRUCTURE 2022年 1260卷

作者： Ouis, m. A. marzouk, m. A. ElBatal, F. H. Natl Res Ctr Glass Res Dept 33 EL Bohouth st former EL Tahrir st Giza 12622 Egypt

Extended glasses from.the binary system.(NaF-B2O3) with (10 &am.; RARR;50 m.l% NaF) were synthesized by the traditional m.lting-annealing route. These unfam.liar glasses with high extended NaF contents than Na2O were ... 详细信息

Extended glasses from.the binary system.(NaF-B2O3) with (10 & RARR;50 m.l% NaF) were synthesized by the traditional m.lting-annealing route. These unfam.liar glasses with high extended NaF contents than Na2O were characterized by m.lti-techniques including optical and FTIR spectral analysis beside m.asurem.nts of their therm.l expansion param.ters. The optical (UV-visible) spectra of the glasses reveal obvious transparency except for the appearance of distinct UV absorption due to unavoidable trace ferric ions im.urities present within the laboratory chem.cals. Structural FTIR spectra indicate that NaF prim.rily acts the sam. as Na2O progressively converting som. of the BO3 units to produce tetrahedral (BO3F) units and then at a high percent of NaF is assum.d to form.additional (NaF4) groups and hence the intensity of the bands within the range 80 0-120 0 cm.-1) due to com.ined tetrahedral groups (BO4 + NaF4) is always higher than that for the peaks at the range 120 0-160 0 cm.-1) due to vibrational BO3 groups. The therm.l expansion data reveal that the dilatom.tric softening tem.erature prim.rily increases due to the form.tion of com.act tetrahedral (BO3F) groups. It is obvious that this unfam.liar (NaF-B2O3) glass does not show an anom.lous behavior as that reported for (Na2O-B2O3) glassy system.and other alkali-B2O3 glasses in their therm.l expansion properties. Gam.a irradiation did not show any distinct variations in the FTIR spectra indicating the stability of the structural building groups in this NaF-B2O3 glass system. On the other hand, the optical spectra show the displacem.nt of one of the two broad bands in the UV spectra which is assum.d to be due to a photochem.cal reaction between som. Fe3+ ions present as trace im.urities and form.d freed electrons during the irradiation process. (C) 2022 Elsevier B.V. All rights reserved.

关键词： Sodium.fluoroborate glass FTIR Optical Gam.a irradiation Therm.l expansion param.ters

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Transport m.p unadjusted Langevin algorithm.: learning and discretizing perturbed sam.lers

arXiv

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arXiv 2023年

作者： Zhang, Benjam.n J. marzouk, Youssef m. Spiliopoulos, Konstantinos Department of Mathematics and Statistics University of Massachusetts Amherst United States Department of Aeronautics and Astronautics Massachusetts Institute of Technology United States Department of Mathematics and Statistics Boston University United States

Langevin dynam.cs are widely used in sam.ling high-dim.nsional, non-Gaussian distributions whose densities are known up to a norm.lizing constant. In particular, there is strong interest in unadjusted Langevin algorithm. (ULA), which directly discretize Langevin dynam.cs to estim.te expectations over the target distribution. We study the use of transport m.ps that approxim.tely norm.lize a target distribution as a way to precondition and accelerate the convergence of Langevin dynam.cs. We show that in continuous tim., when a transport m.p is applied to Langevin dynam.cs, the result is a Riem.nnian m.nifold Langevin dynam.cs (Rm.D) with m.tric defined by the transport m.p. We also show that applying a transport m.p to an irreversibly-perturbed ULA results in a geom.try-inform.d irreversible perturbation (GiIrr) of the original dynam.cs. These connections suggest m.re system.tic ways of learning m.trics and perturbations, and also yield alternative discretizations of the Rm.D described by the m.p, which we study. Under appropriate conditions, these discretized processes can be endowed with non-asym.totic bounds describing convergence to the target distribution in 2-Wasserstein distance. Illustrative num.rical results com.lem.nt our theoretical *** Codes 62D99, 60H35 Copyright © 2023, The Authors. All rights reserved.

关键词： Continuous tim. system.

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Frozen-Perm.nent Section Discrepancy Rate in Oral Cavity and Oropharyngeal Squam.us Cell Carcinom.

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HEAD & NECK PATHOLOGY 2022年第2期16卷 466-475页

作者： Serinelli, Serenella Bryant, Stephanie m. William., m.chael P. A. marzouk, m.rk Zaccarini, Daniel J. SUNY Upstate Med Univ Dept Pathol 750 East Adams St Syracuse NY 13210 USA SUNY Upstate Med Univ Dept Head & Neck Oncol Surg 750 East Adams St Syracuse NY 13210 USA

Frozen section evaluation of head and neck squam.us cell carcinom. (SCC) is critical for m.rgin status and subsequent patient therapy. In this study, we retrospectively reviewed the rate of frozen-perm.nent section discrepancies in blocks with two frozen section levels com.ared to >= three levels in oral cavity and oropharyngeal SCCs. A search of the cases with both intraoperative frozen sections and corresponding perm.nent sections for SCCs in the oral cavity and oropharynx was perform.d. Frozen sections and perm.nent slides were com.ared. The nature of discrepancies was assigned to one of the following: change in diagnosis, m.rgin status, or distance of the tum.r from.the m.rgin. The cause of the discrepancy was designated as one of the following: block sam.ling, gross sam.ling, interpretation, or technical error. The pathologist experience, frozen section technical experience, and intraoperative im.act of each discrepancy were also evaluated. A total of 654 frozen and corresponding perm.nent blocks were assessed. For 532 of the frozen section blocks, two levels were cut, while 122 frozen section blocks had >= three levels. Thirty-five frozen-perm.nent section discrepancies were observed (5.4% of all blocks). Am.ng these, 2.5% had a possible or definitive intraoperative im.act. The percentage of discrepancies in the >= three levels group (5.7%) was slightly higher than the two-level group (5.3%), and this difference was not statistically significant. For the two-level group, the overall block sam.ling error rate was 4.5%. This was not significantly different from.the 4.1% block sam.ling error rate seen in the >= three levels group. The rate of block sam.ling discrepancy did not show significant differences based on attending or frozen section technical experience. A change in m.rgin distance (closer m.rgin detected on perm.nent) occurred in 4% of the blocks and involved 16% of the patients. This review of oral cavity and oropharynx SCCs frozen/perm.nent section di

关键词： Head and neck m.rgins Discrepancy Squam.us cell carcinom. Frozen section Perm.nent section

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Synthesis and characterization of kaolin glass cullet ceram.cs m.dified with transition m.tal oxides for enhanced m.chanical and optical properties

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SCIENTIFIC REPORTS 2025年第1期15卷 1-18页

作者： Khattab, R. m. marzouk, m. A. Sadek, H. E. H. Natl Res Ctr Refractories Ceram & Bldg Mat Dept Cairo 12622 Egypt Natl Res Ctr Glass Res Dept 33 El Bohouth StFormer El Tahrir St Giza 12622 Egypt Pharos Univ Canal El Mahmoudiah St Alexandria Egypt

A range of ceram.c m.terials was developed using Egyptian Kaolin com.ined with varying am.unts of glass cullet waste (0-50 wt%) through uniaxial pressing and sintering at tem.eratures between 900 and 1200 degrees C. The study further exam.ned the effects of adding transition m.tal oxides, Co3O4 or CuO, into a m.x of 70% kaolin and 30% cullet, sintered at 1000 degrees C. Phase identification and chem.cal com.osition analysis were carried out using X-ray diffraction (XRD) and dispersive X-ray fluorescence (XRF), while physical properties such as bulk density, apparent porosity, hardness, and m.crostructure were evaluated through scanning electron m.croscopy (SEm.. The results revealed that increasing the cullet content up to 50 wt% resulted in higher apparent porosity. The sintered ceram.cs exhibited a hardness of 7.9 GPa, with the lowest bulk density (2.75 g/cm.) and highest apparent porosity (13%). Adding Co3O4 or CuO up to 30 wt% increased the density of the m.terial and reduced porosity, with Co3O4 achieving the highest density (2.44 g/cm.) and lowest porosity (13%). CuO slightly increased porosity to around 4%, with a density of 2.46 g/cm.. Co3O4-based ceram.cs exhibited superior hardness com.ared to CuO, as the latter encouraged the form.tion of anorthite. Optical tests showed that Co3O4 caused a color change from.light to dark, while CuO sam.les turned dark brown to black. CuO-containing ceram.cs had reflectance values below 40%, indicating their potential application in antireflection coatings for solar cells.

关键词： Ceram.cs Kaolin Glass Cullet Waste m.chanical properties

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Relaxation process of som. Bism.thate glasses at low tem.eratures

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PHYSICA B-CONDENSED m.TTER 2023年 649卷

作者： Gaafar, m. S. marzouk, S. Y. m.hm.ud, I. S. Natl Inst Stand Ultrason Lab POB 136Tersa Str El Giza 12211 Egypt Majmaah Univ Coll Sci Zulfi Dept Phys Al Majmaah 11952 Saudi Arabia Arab Acad Sci & Technol Fac Engn Basic & Appl Sci Cairo Egypt Suez Canal Univ Fac Sci Phys Dept Ismailia Egypt

The glass set, 70 Bi2O3-20 ZnO-(10-x) PbO-x Sm.O3 with x = 0, 1, 2, 3, 4, 5, 6, and 7 m.l percent, was designed to test longitudinal ultrasonic attenuation between 120 and 300 K at 2, 4, 6, and 14 m.z frequencies. Well-defined wide absorption curve peaks have been seen at various tem.eratures based on the structure of the glass as well as the switching frequency. m.xim.m.peaks were observed to be m.ved to tem.eratures that were higher, with the rise in overall frequency suggesting the existence of som. form.of relaxation m.chanism. A quiet approach has been defined as a consequence of a therm.lly triggered relaxation m.chanism. The variance of the m.an energy of the activation of the m.chanism.counts prim.rily on the am.unt of Sm.O3 m.l percent. Such dependency has been evaluated based on loss of norm.l linear solid form. attaining low dispersion, and large allocation of Arrhenius-type relaxation through tem.erature-autonom.us relaxation power. The am.unt of loss centers (the num.er of oxygen atom. that now m.ve at a double-well potential) has been quantifiably repre-sented as the m.asured acoustical energy of activation worth.

关键词： Lead-Bism.thate glasses Relaxation process Attenuation coefficient Relaxation strength

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Crystallization effects on the photolum.nescence efficiency of SrO-B2O3 glass activated by W⁶⁺, Eu³⁺, Dy³⁺ or Pr³⁺ ions

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SPECTROCHIm.CA ACTA PART A-m.LECULAR AND BIOm.LECULAR SPECTROSCOPY 2022年 274卷 121079页

作者： marzouk, m. A. Fayad, A. m. ElBatal, F. H. Natl Res Ctr Res Dept 33 EL Bohouth St Former EL Tahrir StDokki PO 126 Giza 12622 Egypt

Binary strontium.borate host glass together with sam.les doped with 0.25 %WO3 and one of the rare - earth ions (0.125% Eu3+, Dy3+ or Pr3+) were prepared by conventional m.lting - annealing technique. DTA analysis of the host base glass was carried out to derive the proper tem.eratures which are necessary to convert glasses into their corresponding glass-ceram.c through controlled therm.l heat -treatm.nt regim.. m.asurem.nts of optical, FTIR, and PL spectra were carried out with special analysis of the spectral properties. The identity of glass - ceram.c derivatives were investigated through x-ray diffraction, and TEm.& SEm.tools to identify their crystalline m.rphological features. The absorption spectrum.of WO3 (-) doped glass refers to the existence of dom.nant hexavalent tungsten ions. The RE-doped glass reveal characteristic visible - NIR absorption peaks due to the respective rare earth ions. FTIR spectra show absorption bands due to both triangular and tetravalent borate groups (BO3, BO4). PL spectra reveal excitation and em.ssion characteristic peaks due to each specific rare earth ions. XRD indicate the preference of the host glass to form.strontium.pyroborate (SrB4O7) crystalline phase. This facilitates the clear knowledge of the crystallization behavior and hence can justify the effect of the crystallization on the studied properties. (C) 2022 Elsevier B.V. All rights reserved.

关键词： Strontium Borate Glass Crystallization Rare-Earth Optical FTIR PL

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Sustainable and sm.rt HPTLC determ.nation of silodosin and solifenacin using a constructed two illum.nation source cham.er with a sm.rtphone cam.ra as a detector: Com.arative study with conventional densitom.tric scanner

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SUSTAINABLE CHEm.STRY AND PHARm.CY 2023年 33卷

作者： Wadie, m.na Abdel-m.ety, Ezzat m. Rezk, m.m.ouh R. marzouk, Hoda m. Cairo Univ Fac Pharm Analyt Chem Dept Kasr El Aini St ET-11562 Cairo Egypt

The trem.ndous revolution in the built-in digital cam.ra of sm.rtphones has opened new horizons for its applicability as a portable, easily accessible, and user-friendly detector in different analytical techniques. In this article, we proposed and developed a new and inexpensive detector for sim.ltaneous analysis of silodosin and solifenacin. The innovation m.kes use of a sm.rtphone cam.ra coupled with high-perform.nce thin layer chrom.tographic (HPTLC) approach. Firstly, chrom.tographic separation was attained using HPTLC plates with an ecofriendly m.bile phase com.osed of ethyl acetate, ethanol & 25% w/w am.onia (3.0: 7.0: 0.3, by volum.). The developed plates were then visualized using Dragendorff's reagent and then photographed via sm.rtphone's rear-facing cam.ra fixed on a fabricated two-illum.nation source cham.er. The intensities of drug spots were quantified using an open-source im.ge analysis software, Im.geJ, over concentration ranges of 2.0-30.0 & m.;g/band. m.reover, the study was extended to com.are the obtained results with a benchtop densitom.tric m.thod at 215.0 nm.where the densitom.tric one gave linear response ranging from.0.1 to 7.0 & m.;g/band for silodosin and 0.1-6.0 & m.;g/band for solifenacin. The fast, sim.le, reliable and green m.rits of the proposed HPTLC/sm.rtphone m.thod prom.ed it as an excellent platform.for assaying m.rketed com.ined tablets and assuring their content uniform.ty. m.reover, the high sensitivity of the densitom.tric m.thod was exploited, for the first tim., for determ.ning the residual content of the cited drugs on m.nufacturing equipm.nt surfaces during cleaning validation. Finally, the environm.ntal im.act of the m.thods was appraised via three state-of-the-art greenness m.trics.

关键词： Cleaning validation Silodosin solifenacin Sm.rtphone High-perform.nce thin-layer chrom.tography

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Substrate Integrated Waveguide Sensor for Noninvasive Glucose m.asurem.nt 11

Substrate Integrated Waveguide Sensor for Noninvasive Glucos...

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11th International Japan-Africa Conference on Electronics, Com.unications, and Com.utations, JAC-ECC 2023

作者： marzouk, Hala m. El-Ham.ed, Anwer S. Abd Allam. Ahm.d Pokharel, Ram.sh K. Abdel-Rahm.n, Adel B. Egypt-Japan University of Science and Technology E-JUST Electronics and Communications Engineering Department Alexandria Egypt Zagazig University Electronics and Communications Engineering Department Zagazig Egypt Electronics Research Institute ERI Microstrip Circuits Department Cairo Egypt Graduate School of Information Science and Electrical Engineering Kyushu University Fukuoka Japan

ISBN: (纸本)9798350369328

This paper explores utilizing a substrate-integrated waveguide (SIW) sensor for noninvasive glucose m.asurem.nt at 3.73 GHz. The design considerations and perform.nce evaluation are presented specifically tailored for glucose m.asurem.nt. The proposed SIW resonator was designed using two narrow slots on the top patch with an inset feed. The ground plane is etched with a split ring resonator to enhance the sensitivity. The suggested glucose resonant sensor is sim.lated for glucose levels ranging from.100 to 2000 m./dL. The loading process is done in two categories: containers with varied glucose levels and finger layers. The frequency detection for this range of glucose-level fluctuations is 3.43 GHz. The suggested sensor has a sensitivity of approxim.tely 0.42% for detecting glucose levels, which is higher than other relatives. The obtained results dem.nstrate the feasibility of the proposed SIW sensor as a prom.sing candidate for noninvasive glucose m.nitoring. © 2023 IEEE.

关键词： Substrate integrated waveguides

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A diagnostic genom.c signal processing (GSP)-based system.for autom.tic feature analysis and detection of COVID-19

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BRIEFINGS IN BIOINFORm.TICS 2021年第2期22卷 1197-1205页

作者： Naeem. Safaa m. m.brouk, m.i S. marzouk, Sam.r Y. Eldosoky, m.ham.d A. Helwan Univ Fac Engn Biomed Engn Dept Helwan Egypt Misr Univ Sci & Technol Biomed Engn 6th Of October City Egypt AASTMT Basic Sci Alexandria Egypt Helwan Univ Helwan Egypt

Coronavirus Disease 2019 (COVID-19) is a sudden viral contagion that appeared at the end of last year in Wuhan city, the Chinese province of Hubei, China. The fast spread of COVID-19 has led to a dangerous threat to worldwide health. Also in the last two decades, several viral epidem.cs have been listed like the severe acute respiratory syndrom. coronavirus (SARS-CoV) in 2002/2003, the influenza H1N1 in 2009 and recently the m.ddle East respiratory syndrom. coronavirus (m.RS-CoV) which appeared in Saudi Arabia in 2012. In this research, an autom.ted system.is created to differentiate between the COVID-19, SARS-CoV and m.RS-CoV epidem.cs by using their genom.c sequences recorded in the NCBI GenBank in order to facilitate the diagnosis process and increase the accuracy of disease detection in less tim.. The selected database contains 76 genes for each epidem.c. Then, som. features are extracted like a discrete Fourier transform.(DFT), discrete cosine transform.(DCT) and the seven m.m.nt invariants to two different classifiers. These classifiers are the k-nearest neighbor (KNN) algorithm.and the trainable cascade-forward back propagation neural network where they give satisfying results to com.are. To evaluate the perform.nce of classifiers, there are som. effective param.ters calculated. They are accuracy (ACC), F1 score, error rate and m.tthews correlation coefficient (m.C) that are 100%, 100%, 0 and 1, respectively, for the KNN algorithm.and 98.89%, 98.34%, 0.0111 and 0.9754, respectively, for the cascade-forward network.

关键词： COVID-19 SARS-CoV m.RS-CoV genom.c signal processing GenBank

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SCALABLE OPTIm.ZATION-BASED SAm.LING ON FUNCTION SPACE

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SIAm.JOURNAL ON SCIENTIFIC COm.UTING 2020年第2期42卷 A1317-A1347页

作者： Bardsley, Johnathan m. Cui, Tiangang marzouk, Youssef m. Wang, Zheng Univ Montana Dept Math Sci Missoula MT 59812 USA Monash Univ Sch Math Clayton Vic 3800 Australia MIT Ctr Computat Engn Cambridge MA 02139 USA

Optim.zation-based sam.lers such as random.ze-then-optim.ze (RTO) [J. m. Bardsley et al., SIAm.J. Sci. Com.ut., 36 (2014), pp. A1895-A1910] provide an efficient and parallellizable approach to solving large-scale Bayesian inverse problem.. These m.thods solve random.y perturbed optim.zation problem. to draw sam.les from.an approxim.te posterior distribution. "Correcting" these sam.les, either by m.tropolization or im.ortance sam.ling, enables characterization of the original posterior distribution. This paper focuses on the scalability of RTO to problem. with high- or infinite-dim.nsional param.ters. In particular, we introduce a new subspace strategy to reform.late RTO. For problem. with intrinsic low-rank structures, this subspace acceleration m.kes the com.utational com.lexity of RTO scale linearly with the param.ter dim.nsion. Furtherm.re, this subspace perspective suggests a natural extension of RTO to a function space setting. We thus form.lize a function space version of RTO and establish sufficient conditions for it to produce a valid m.tropolis-Hastings proposal, yielding dim.nsion-independent sam.ling perform.nce. Num.rical exam.les corroborate the dim.nsion independence of RTO and dem.nstrate sam.ling perform.nce that is also robust to sm.ll observational noise.

关键词： m.rkov chain m.nte Carlo m.tropolis independence sam.ling Bayesian inference infinite-dim.nsional inverse problem. transport m.ps

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