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Alkaline igneous rocks,a potential source of rare metals and radioactive minerals:Case study at Amreit area,south Eastern Desert,Egypt

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Acta Geochimica 2025年第1期44卷 189-214页

作者： Baaha M.Emad Nuclear Materials Authority El MaadiP.O.Box:530CairoEgypt

Alkaline igneous rocks represent one of the most economically important resources of radioactive minerals and rare *** field observations and petrographic studies are integrated with whole-rock geochemical analyses and Gamma ray spectroscopy data of alkaline rocks associated with the Amreit *** fieldwork was achieved by the collection of more than forty samples from alkaline granites and alkaline *** youngest rocks cropping out in the study area are the cogenetic alkaline rocks,ranging from alkaline granite to alkaline *** alkaline rocks are composed essentially of K-feldspar,alkali amphiboles(arfvedsonite),and sodic pyroxene,with accessories such as zircon,apatite,and *** characterization of the highly radioactive zones in both alkaline granite and alkaline syenite displays enrichment in monazite,thorite,zircon,ferro-columbite,xenotime,and allanite *** analyses indicate that the Amreit rocks are alkaline with peralkaline affinity and have high concentrations of total alkalis(K_(2)o+Na_(2)o),large ion lithophile elements(LILEs;Ba and Rb),high field strength elements(HFSEs;Y,Zr and Nb),rare earth elements(REEs)and significantly depleted in K,Sr,p,Ti,and Eu,typically of post-collision A-type ***,the Amreit alkaline igneous rocks are classified as within plate granites and display A2 subtype *** fractionation of K-feldspars played a distinctive role during the magmatic evolution of these alkaline *** geochemical characteristics indicate that the studied alkaline igneous rocks which were originated by fractional crystallization of alkaline magmas were responsible for the enrichment of the REE and rare metals in the residual *** high radioactivity is essentially related to accessory minerals,such as zircon,allanite,and *** alkaline granite is the most U-and Thrich rock,where radioactivity level reaches up to 14.7 ppm(181.55 Bq/kg)e U,40.6 ppm(164.84 Bq/kg)e

关键词： Amreit area Alkaline rocks Radioactivity Geochemistry post-collision A-type granite Egypt

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Geochemistry of Neop.o.erozoic metavolcanic rocks from the Tahtai Logomiti area,Tigrai,Northern Ethiopia:Implication for petrogenesis and tectonic settings

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Acta Geochimica 2025年第1期44卷 128-144页

作者： Azeb Gebremicale Mulugeta Alene Teklay Gidey School of Earth Sciences Mekelle UniversityP.O.Box:231MekelleEthiopia School of Earth Sciences Addis Ababa UniversityP.O.Box:1176Addis AbabaEthiopia Department of Earth Environmental and Planetary SciencesCase Western Reserve UniversityClevelandOHUSA Faculty of Mines Aksum UniversityP.O.Box:1010AksumEthiopia

The Tahtai Logomiti area is characterized by metavolcanic and metavolcaniclastic interbedded with clastic and carbonate metasedimentary rocks of Neop.o.erozoic *** geological,petrographic,major,and trace elements data were used to evaluate the metamorphism,petrogenesis,and paleo-tectonic setting of the *** field and petrographic observation indicate that the area has undergone greenschist facies *** on mineralogy and geochemical attributes,these metavolcanic rocks are classified as basalt,basaltic-andesite,andesite,and *** moderate degrees of light rare earth element(LREE)enrichment,flat heavy rare earth element(HREE)pattern,and low Nb/Y ratio,represent shallow mantle *** addition to that,the Tio_(2)/Yb ***/Yb diagram,high(La/Yb)N ratio(>3.44),indicates shallow melting and depleted magma ***,the high ratios of(Th/Ta)>3.8,(La/Ta)>38,and low ratios of(Th/La)pb content would indicate crustal contamination of the *** discrimination diagram and trace element ratios(Nb/Y,La/Sc,La/Y,and La/Th)indicate that the metavolcanic rocks have a calc-alkaline *** addition,the ZrNb-Y and Th-Hf-Ta p.o.s show that the rocks formed under a volcanic-arc *** general petrological and geochemical characteristics of the Tahtai Logomiti metavolcanic rocks suggest that the area is associated with subduction-related arc accretion of the Arabian Nubian Shield.

关键词： Deformation Metamorphism Foliation Calc-alkaline Neop.o.erozoic Arabian Nubian Shield

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Analysis of Linear and Nonlinear Vibrations of Composite Rectangular Sandwich plates with Lattice Cores

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Computers, Materials & Continua 2025年第1期82卷 223-257页

作者： Alireza Moradi Alireza Shaterzadeh Faculty of Mechanical Engineering Shahrood University of TechnologyShahroodP.O.Box ***Iran

For the first time,the linear and nonlinear vibrations of composite rectangular sandwich plates with various geometric patterns of lattice core have been analytically examined in this *** plate comprises a lattice core located in the middle and several homogeneous orthotropic layers that are symmetrical relative to *** this purpose,the partial differential equations of motion have been derived based on the first-order shear deformation theory,emp.o.ing Hamilton’s principle and Von Kármán’s nonlinear displacement-strain ***,the nonlinear partial differential equations of the plate are converted into a time-dependent nonlinear ordinary differential equation(Duffing equation)by applying the Galerkin *** the solution of this equation,the natural frequencies are ***,to calculate the non-linear frequencies of the plate,the non-linear equation of the plate has been solved analytically using the method of multiple ***,the effect of some critical parameters of the system,such as the thickness,height,and different angles of the stiffeners on the linear and nonlinear frequencies,has been analyzed in *** confirmthe solution method,the results of this research have been compared with the reported results in the literature and finite elements in ABAQUS,and a perfect match is *** results reveal that the geometry and configuration of core ribs strongly affect the natural frequencies of the plate.

关键词： Free vibration composite sandwich plate lattice core galerkin method Duffing equation multiple scales method

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on the Sense of Convergence in the Dyadic Representation Theorem

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Acta Mathematica Sinica,English Series 2025年第1期41卷 472-496页

作者： Tuomas Hytonen Department of Mathematics and Systems Analysis Aalto UniversityP.O.Box 11100FI-00076 AaltoFinland Department of Mathematics and Statistics University of HelsinkiP.O.Box 68FI-00014 University of HelsinkiFinland

The dyadic representation of any singular integral operator,as an average of dyadic model operators,has found many *** for many purposes it is enough to have such a representation for a“suitable class”of test functions,we show that,under quite general assumptions(essentially minimal ones to make sense of the formula),the representation is actually valid for all pairs(f,g)∈L^(p)(R^(d))×L^(p')(R^(d)),not just test functions.

关键词： Singular integral dyadic shift

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Continuous-flow columns packed with zero-valent iron and iron sulfide as a feasible strategy to remediate the persistent contaminant nitroguanidine

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Defence Technology(防务技术) 2025年第1期43卷 26-34页

作者： Youngjae Yu Erika E.Rios-Valenciana Robert A.Root Reyes Sierra-Alvarez Jon Chorover Jim A.Field Department of Chemical and Environmental Engineering The University of ArizonaP.O.Box 210011TucsonAZ 85721USA Department of Environmental Science The University of ArizonaTucsonAZ 85721USA

The insensitive munitions compound nitroguanidine(NQ)is used by the *** to avoid unintended ***,NQ also represents an emerging contaminant whose environmental emissions can cause toxicity toward aquatic organisms,indicating the need for effective remediation ***,we investigated the feasibility of treating water contaminated with NQ in continuous-flow columns packed with zero-valent iron(ZVI)or iron sulfide(FeS).Initially,the impact of pH on NQ transformation by ZVI or FeS was evaluated in batch *** pseudo first-order rate constant for NQ transformation(k_(1,NQ))by ZVI was 8-10 times higher at pH 3.0 compared to pH 5.5 and 7.0,whereas similar k_(1,NQ)values were obtained for FeS at pH *** on these findings,the influent p H fed to the ZVIand Fe S-packed columns was adjusted to 3.0 and 5.5,*** reactors transformed NQ into nitrosoguanidine(Nso Q).Further transformation of Nso Q by ZVI p.o.uced aminoguanidine,guanidine,and cyanamide,whereas Nso Q transformation by Fe S p.o.uced guanidine,ammonium,and traces of *** outperformed Fe S as a reactive material to remove *** ZVI-packed column effectively removed NQ below detection even after 45 d of operation(490 pore volumes,pV).In contrast,NQ breakthrough(removal efficiencyobserved after 18 d(180 pV)in the Fe S-packed *** high NQ removal efficiency and long service life of the ZVI-packed column(>490 pV)suggest that the technology is a p.o.ising app.o.ch for NQ treatment in packed-bed reactors and in situ remediation.

关键词： Continuous water treatment Iron-based minerals Chemical reduction pH Aminoguanidine Guanidine

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Iron-p.o.oted zirconia-alumina sup.o.ted Ni catalyst for highly efficient and cost-effective hydrogen p.o.uction via dry reforming of methane

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Journal of Environmental Sciences 2025年第2期148卷 274-282页

作者： Ahmed S.Al-Fatesh Naitik patel Vijay Kumar Srivastava Ahmed I.osman David W.Rooney Anis H.Fakeeha Ahmed E.Abasaeed Mohammed F.Alotibi Rawesh Kumar Chemical Engineering Department College of EngineeringKing Saud UniversityP.O.Box 800Riyadh 11421Saudi Arabia Department of Chemistry Indus UniversityAhmedabadGujarat 382115India School of Chemistry and Chemical Engineering Queen’s University BelfastBelfast BT95AGNorthern IrelandUK Institute of Refining and petrochemicals Technologies King Abdulaziz City for Science and Technology(KACST)P.O.Box 6086Riyadh 11442Kingdom of Saudi Arabia

Developing cost-effective and high-performance catalyst systems for dry reforming of methane(DRM)is crucial for p.o.ucing hydrogen(H_(2))***,we investigate using iron(Fe)as a p.o.oter and major alumina sup.o.t in Ni-based catalysts to imp.o.e their DRM *** addition of iron as a p.o.otor was found to add reducible iron species along with reducible Nio species,enhance the basicity and induce the deposition of oxidizable *** incorporating 1 wt.%Fe into a 5Ni/10ZrAl catalyst,a higher Co_(2) interaction and formation of reducible"Nio-species having strong interaction with sup.o.t"was observed,which led to an∼80%H_(2) yield in 420 min of Time on Stream(ToS).Further increasing the Fe content to 2 wt.%led to the formation of additional reducible iron oxide species and a noticeable rise in H_(2) yield up to 84%.Despite the severe weight loss on Fe-p.o.oted catalysts,high H_(2) yield was maintained due to the p.o.er balance between the rate of CH_(4) decomposition and the rate of carbon deposit ***,incorporating 3 wt.%Fe into the 5Ni/10ZrAl catalyst resulted in the highest Co_(2) interaction,wide presence of reducible Nio-species,minimumgraphitic deposit and an 87%H_(2) *** findings suggest that ironp.o.oted zirconia-alumina-sup.o.ted Ni catalysts can be a cheap and excellent catalytic system for H_(2) p.o.uction via DRM.

关键词： Dry reforming of methane Coke resistant Hydrogen p.o.uction Cheap catalyst Fe-p.o.oted catalyst

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An Enhanced Lung Cancer Detection App.o.ch Using Dual-Model Deep Learning Technique

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 835-867页

作者： Sumaia Mohamed Elhassan Saad Mohamed Darwish Saleh Mesbah Elkaffas Department of Information Technology Institute of Graduate Studies and ResearchAlexandria UniversityAlexandria21526Egypt College of Computing and Information Technology Arab Academy for ScienceTechnology and Maritime TransportAlexandriaP.O.Box 1029Egypt

Lung cancer continues to be a leading cause of cancer-related deaths worldwide,emphasizing the critical need for imp.o.ed diagnostic *** detection of lung tumors significantly increases the chances of successful treatment and ***,current diagnostic methods often fail to detect tumors at an early stage or to accurately pinpoint their location within the lung ***-model deep learning technologies for lung cancer detection,while beneficial,cannot capture the full range of features present in medical imaging data,leading to incomplete or inaccurate ***,it may not be robust enough to handle the wide variability in medical images due to different imaging conditions,patient anatomy,and tumor *** overcome these disadvantages,dual-model or multi-model app.o.ches can be *** research focuses on enhancing the detection of lung cancer by utilizing a combination of two learning models:a Convolutional Neural Network(CNN)for categorization and the You only Look once(YoLov8)architecture for real-time identification and pinpointing of *** automatically learn to extract hierarchical features from raw image data,capturing patterns such as edges,textures,and complex structures that are crucial for identifying lung ***8 incorporates multiscale feature extraction,enabling the detection of tumors of varying sizes and scales within a single *** is particularly beneficial for identifying small or irregularly shaped tumors that may be challenging to ***,through the utilization of cutting-edge data augmentation methods,such as Deep Convolutional Generative Adversarial Networks(DCGAN),the suggested app.o.ch can handle the issue of limited data and boost the models’ability to learn from diverse and comprehensive *** combined method not only imp.o.ed accuracy and localization but also ensured efficient real-time p.o.essing,which is crucial for practical clinical applicati

关键词： Lung cancer detection dual-model deep learning technique data augmentation CNN YoLov8

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Resonant Activation Induced by Four-Value Noise

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Communications in Theoretical physics 2008年第2期49卷 385-390页

作者： HAN Yin-Xia LI Jing-Hui p.o. box 58 Faculty of Science Ningbo University Ningbo 315211 China

The phenomenon of the resonant activation （RA） of a particle over a fluctuating potential barrier with a four-value noise is investigated. It is shown that the mean first passage time （MFpT） displays six minima as the function of the transition rates γ1, γ2, γ3, γ4, γ5, and 76 of the four-value noise, respectively. In addition, the effect of other parameters of the system, such as the noise strength D of the additive Gaussian white noise and the parameter value a, b, c, and d of the four-value noise, on the RAs is also investigated.

关键词： resonant activation four-value noise mean first passage time

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Stochastic Resonance of Single (Independent of Each other) p.o.ein Motor System with Fluctuating potential Barrier

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Communications in Theoretical physics 2008年第4期49卷 945-950页

作者： LI Jing-Hui p.o. box 58 Faculty of Science Ningbo University Ningbo 315211 China

A single （independent of each other） p.o.ein motor system with fluctuating potential barrier and subject to sine electric field is investigated. We first derive the app.o.imate Langevin equation of this system with fluctuating potential barrier. Then from this app.o.imate Langevin equation, we calculate the signal-to-noise ratio （SNR） in the adiabatic limit. The phenomenon of stochastic resonance is found for this p.o.ein motor system with fluctuating potential barrier.

关键词： stochastic resonance p.o.ein motor fluctuating potential barrier

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Two Stochastic Resonances Induced by Two Different Multiplicative Telegraphic Noises for an Electric System

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Communications in Theoretical physics 2008年第11期50卷 1159-1164页

作者： LI Jing-Hui Faculty of Science P.O. Box 58 Ningbo University Ningbo 315211 China

In this paper,an electric system with two dichotomous resistors is *** is shown that thissystem can display two stochastic resonances,which are the amplitude of the periodic response as the functions of thetwo dichotomous resistors strengthes *** the limits of Gaussian white noise and shot white noise(i.e.,thetwo noises are both Gaussian white noise or shot white noise),no phenomena of resonance *** further study,we find that when the system is with three or more multiplicative telegraphic noises,there are three or more stochasticresonances.

关键词： stochastic resonance noise

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