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Chinese Chemical Letters 2015年第6期26卷 690-694页

作者： mohamed S.A.El-Gaby Jehan A.micky nadia m.saleh Yousry A.Ammar Heba S.A.mohamed Chemistry Department Faculty of ScienceAl-Azhar University at Assiut Chemistry Department Faculty of Science (Girl’s)Al-Azhar University Chemistry Department Faculty of ScienceAl-Azhar University Photochemistry Department National Research CenterEl-DokkiGizaEgypt

2-Aminocyclopenta[d]pyrimidines 3a-c were achieved via a one-pot, three-component reactions of cyclopentanone 1, aromatic aldehyde and guanidine hydrochloride （1：2：1 molar ratio）. Also, cyclization of 2,5-bis-（arylmethylidene）cyclopentanones 2 with guanidine hydrochloride （1：1 molar ratio） in methanol in the presence of sodium methoxide afforded cyclopenta-[d]pyrimidines 3. Compound 3c has been shown to be a useful building block for the synthesis of some novel pyrimido[ 1,2-a]pyrimidines 5, 7 and 12. The structures of the newly synthesized compounds were confirmed on the basis of analytical and spectral data,

关键词： multicomponent reaction Cyclopenta[d]pyrimidine Pyrimido[1 2-a]pyrimidine Cyclopentanone

Influence of erbium on structural,and charged particles,photons,and neutrons shielding properties of Ba_(1-x)Er_(x)SnO_(3) perovskite ceramics

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Journal of Rare Earths 2024年第4期42卷 724-732页

作者： m.K.h.Hamad Nidal Dwaikat m.H.A.mhareb m.I.Sayyed R.m.Hamad Y.S.m.Alajerami m.A.Almessiere Gameel saleh Ahmad Hussein Alomari K.A.Ziq Department of Basic Sciences School of Social and Basics SciencesAl Hussein Technical UniversityKing Abdullah II St 242Amman11831Jordan Department of Physics College of Engineering and PhysicsInterdisciplinary Research Center for Advanced MaterialsKing Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Department of Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam31441Saudi Arabia Basic and Applied Scientific Research Center Imam Abdulrahman Bin Faisal UniversityP0.Box 1982Dammam31441Saudi Arabia Department of Physics Faculty of ScienceIsra UniversityAmman11622Jordan Department of Nuclear medicine Research Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Arabia medical Imaging Department Applied Medical Sciences FacultyAl Azhar University-Gaza CityPo.Box 1277Palestine Department of Biophysics Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box1982Dammam 31441Saudi Arabia Department of Biomedical Engineering College of EngineeringImam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Energy&minerals Regulatory Commission Amman11821Jordan

Five perovskite ceramics samples of Ba_(1-x)Er_(x)SnO_(3) with x=0.00,0.05,0.10,0.15,and 0.20 were synthesized using the conventional solid-state reaction *** prepared samples were characterized by X-ray diffraction(XRD),Fourier transforms infrared(FTIR),and UV-Vis *** shielding properties against ionizing radiation were also *** XRD analysis shows the perovskite cubic structure as the major phase in all *** FTIR reveals a distinctive band around 614-620 cm^(-1) ascribed to the antisymmetric O-Sn-O ***-Vis spectroscopy was used to determine the bandgap according to diffuse reflectance,and the results display a fixed enhancement in the bandgap from 3.2 to 3.3 eV for all ***-ray shielding properties of the synthesized samples were experimentally measured and compared with XCOm computational *** relative differences(Δ,%)between experimental and theo retical values are low and fall within the 0.446%-7.10%*** addition of Er leads to the enhanced density,neutron,and gamma shielding *** contrast,charged particles’shielding parameters gradually reduce with rising Er *** results suggest that Ba_(1-x)Er_(x)SnO_(3) samples can be used in different radiation shielding applications.

关键词： Perovskite Ceramics Gamma ray shielding mass stopping power Rare earths

Nonlinear Study on the mechanical Performance of Built-Up Cold-Formed Steel Concrete-Filled Columns under Compression

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Computer modeling in Engineering & Sciences 2024年第6期139卷 3435-3465页

作者： Oulfa Harrat Yazid Hadidane S.m.Anas Nadhim Hamah Sor Ahmed Farouk Deifalla Paul O.Awoyera nadia Gouider Civil Engineering Laboratory Faculty of TechnologyDepartment of Civil EngineeringBadji Mokhtar-Annaba UniversityP.O.Box 12Annaba23000Algeria Department of Civil Engineering Faculty of Engineering and TechnologyJamia Millia Islamia(A Central University)New Delhi110025India Civil Engineering Department University of GarmianKalar46021Iraq Department of Civil Engineering Harran UniversitySanliurfa63510Turkey Structural Engineering and Construction management Department Future University in EgyptNew Cairo11835Egypt Department of Civil Engineering Covenant UniversityOta112233Nigeria

Given their numerous functional and architectural benefits,such as improved bearing capacity and increased resistance to elastic instability modes,cold-formed steel(CFS)built-up sections have become increasingly developed and used in recent years,particularly in the construction *** paper presents an analytical and numerical study of assembled CFS two single channel-shaped columns with different slenderness and configurations(backto-back,face-to-face,and box).These columns were joined by double-row rivets for the back-to-back and box configurations,whereas they were welded together for the face-to-face *** built-up columns were filled with ordinary concrete of good *** element models were applied,using ABAQUS software,to assess mechanical performance and study the influence of assembly techniques on the behavior of cold-formed columns under axial *** approaches based on Eurocode 3 and Eurocode 4 recommendations for un-filled and concrete-filled columns respectively were followed for the numerical analysis,and concrete confinement effects were also considered per American Concrete Institute(ACI)standards for face-to-face and box *** obtained results indicated a good correlation between the numerical results and the proposed analytical methodology which did not exceed 8%.The failure modes showed that the columns failed due to instabilities such as local and global buckling.

关键词： Cold-formed steel built-up sections slenderness rivets welded axial compression analytical approaches confinement buckling

Kaoline-based catalyst for a high stability desulfurization of sour heavy naphtha in a three-phase oscillatory baffled reactor

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Particuology 2024年第1期84卷 249-260页

作者： Hassan m.Hmood Saba A.Gheni Safaa m.R.Ahmed mudheher m.Ali Hamid Yonis saleh mohammed H.mohammed Awad E.mohammed marwan A.mahomood Hiba R.mohammed Ahmed A.Hassan Adam Harvey North Refineries Company Ministry of OilIraq Chemical Engineering Department Tikrit UniversityIraq ministry of Oil Iraq AL-Hawija Technical Institute Northern Technical UniversityMoselIraq School of Engineering Newcastle UniversityUK

To meet the rapidly increasing demand for energy and the dramatic depletion of conventional crude oil,it is imperative to utilize sour *** no coke being produced,oxidative desulfurization(ODS)of naphtha lowers its sulfur content and average molecular *** this article,we outline a method for heavy naphtha non-extractive ODS using a very stable *** technique involves the use of a solid catalyst with oxygen gas as the *** necessitated relatively high mixing intensities;hence a three-phase Oscillatory Baffled Reactor(OBR)was *** catalyst was based on the zeolite ZSm-5,prepared from natural kaolin by a series of delamination and activation steps and impregnated with Fe.A TiO2 nanolayer was applied,using the sol-gel method,to prevent rapid *** reactor performance was evaluated to minimize the sulfur content in the naphtha *** to the protective coating,the sulfur conversion stabilized at 90%.The results of this work establish the use of natural clay-based catalysts in a continuous,three-phase ODS,particularly with regard to proving long-term *** also showed that modest ODS can be achieved using an environmentally friendly oxidant,at mild operating conditions,whilst maintaining stability.

关键词： Natural kaoline Desulfurization Three-phase Oscillatory baffled reactor

Rare metal-bearing pegmatites from the Southeastern Desert of Egypt:Geology,geochemical characteristics,and petrogenesis

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Chinese Journal Of Geochemistry 2007年第1期26卷 8-22页

作者： Gehad m.saleh Nuclear materials Authority P.O.Box:530 El-MaadiCairoEgypt

The pegmatite province of the Southeastern Desert (SED) is part of a pegmatite district that extends from Egypt (extends to 1200 km2). Rare metal pegmatites are divided into (1) unzoned, Sn-mineralized; (2) zoned Li, Nb, Ta and Be-bearing; and (3) pegmatites and pegmatites containing colored, gem-quality tourmaline. The Rb/Sr data reflect a crustal origin for the rare metal pegmatites and indicate that the original SED magma was generated during the peak of regional metamorphism and predates the intrusion of post-tectonic leucogranites. These bodies developed an early border zone consisting of coarse to very coarse muscovite+quartz+alkali feldspar, followed by an intermediate zone of dominant quartz+feldspar+muscovite rock. Garnet, tourmaline, beryl, galena, pyrite, amblygonite, apatite and monazite are rare accessories in both zones. Cassiterite tends to concentrate in replacement zones and along fractures in albite+quartz+muscovite-rich portions. The highest concentrations of cassiterite occur in irregular greisenized zones which consist dominantly of micaceous aggregates of green Li-rich muscovite, quartz, albite and coarse-grained cassiterite. The different metasomatic post-solidification alterations include sodic and potassic metasomatism, greisenization and tourmalinization. Geochemically, the pegmatite-generating granites have a metaluminous composition, showing a differentiation trend from coarse-grained, unfractionated plagioclase-rich granite towards highly fractionated fine- to medium-grained, local albite-rich rock. Economically important ore minerals introduced by volatile-rich, rare metal-bearing fluids, either primarily or during the breakdown of the primary mineral assemblages, are niobium-tantalum oxides, Sn-oxides (cassiterite), Li-silicates (petalite, spodumene, euctyptite, and pollucite), Li-phosphates (amblygonite, montebrasite and lithopilite) and minor REE-minerals (Hf-zircon, monazite, xenotime, thorian, loparite and yttrio-fluorite). The pol

关键词：埃及东南部沙漠稀有金属伟晶岩地质地球化学特征岩石成因

Parallelization of frequency domain quantum gates:manipulation and distribution of frequency-entangled photon pairs generated by a 21 GHz silicon microresonator

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Advanced Photonics 2024年第3期6卷 60-69页

作者： Antoine Henry Dario A.Fioretto Lorenzo m.Procopio Stéphane monfray Frédéric Boeuf Laurent Vivien Eric Cassan Carlos Alonzo-Ramos Kamel Bencheikh Isabelle Zaquine nadia Belabas Institut Polytechnique de Paris LTCI Université Paris-Saclay CNRS Centre for Nanosciences and Nanotechnology Weizmann Institute of Science STmicroelectronics SAS

Harnessing the frequency dimension in integrated photonics offers key advantages in terms of scalability, noise resilience, parallelization, and compatibility with telecom multiplexing *** ring resonators have been used to generate frequency-entangled states through spontaneous four-wave mixing. However, state-of-the-art integrated resonators are limited by trade-offs among size,spectral separation, and efficient photon pair generation. We have developed silicon ring resonators with a footprint below 0.05 mm2providing more than 70 frequency channels separated by 21 GHz. We exploit the narrow frequency separation to parallelize and independently control 34 single qubit-gates with a single set of three off-the-shelf electro-optic devices. We fully characterize 17 frequency-bin maximally entangled qubit pairs by performing quantum state tomography. We demonstrate for the first time, we believe, a fully connected five-user quantum network in the frequency domain. These results are a step towards a generation of quantum circuits implemented with scalable silicon photonics technology, for applications in quantum computing and secure communications.

关键词： frequency domain integrated photonics quantum gates quantum networks

The Protective Effect of moringa oleifera Leaves Extract on Paracetamol Hepatotoxicity in male Rats

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Journal of Biomedical Science and Engineering 2024年第3期17卷 72-82页

作者： Reham m. Al-Sultan Noorah saleh Al-Sowayan Department of Biology College of Science Qassim University Buraydah Saudi Arabia

In recent years, there has been an increase in concern regarding the effects of paracetamol poisoning on liver tissues, particularly when consumed in large amounts. Some studies have estimated that paracetamol is involved in 56% of acute liver diseases, whereas 0.4% of paracetamol overdose cases result in fatal-ity. In this study, the effects of moringa oleifera on paracetamol toxicity in the liver were explored. It has been demonstrated that moringa oleifera is highly nu-tritious, contains bioactive molecules, and is therapeutically beneficial. many studies have shown that moringa oleifera leaves possess a wide range of biologi-cal properties, including antioxidant, tissue protection, analgesic, antihyperten-sive, and immunomodulatory activities. This study highlights the protective role of moringa oleifera on handling possible paracetamol hepatotoxicity in male rats. .

关键词： moringa oleifera Paracetamol Hepatotoxicity Oxidative Stress

Geochemistry and spectrometric prospection of younger granites and granitic pegmatites bearing uranium mineralization at *** El Rakeb area, Central Eastern Desert, Egypt

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Acta Geochimica 2021年第4期40卷 575-601页

作者： Gehad m.saleh Bahaa m.Emad Ibrahim B.Abdel Kader Nuclear materials Authority El MaadiP.O.Box 530CairoEgypt

The present study deals with the detailed field geology,mineralogy,geochemistry,and spectrometric prospection of rare metals and radioactive minerals associated with granitic pegmatites in the Gabal Um LassafAbu Dob-Um Atelia-Kadabora-Kab El Rakeb area(LDAKK),which are situated in the central Eastern Desert of *** study area is composed of granodiorites and *** latter is dissected by granitic pegmatites with a discriminatory distribution of economically important mineralization(rare-metals and U-Th minerals).The granitic pegmatites display a zoning structure composed of feldspar-rich zones enveloping pockets of mica(mostly muscovite) and all zoning internal quartz ***,the monzogranite and granitic pegmatites are composed of potash-feldspar,albite,and quartz with a small amount of biotite and *** mineralogical investigation of the highly radioactive zones in the granitic pegmatite shows enrichment in kasolite,uranothorite,thorite,xenotime,columbite,zircon,bismuth,and ***,the granitic pegmatites are enriched with high field strength elements(HFSE;Zr,Nb,Th,and U) and ion lithophilic elements(LILE;Rb,and Pb) and depleted in Ba,Sr,and *** are strongly peralkaline to metalumainous except for two samples,which are *** are formed by partial melting of metagreywackes at *** studied granitic pegmatites could belong to the NYF family(Niobium-Yttrium-Fluorine family) according to the geochemistry of the trace *** studied granitic pegmatites show deep negative Eu anomaly and display a strong m-type tetrad effect of rare earth *** field spectroscopy measurements showed the localization of the radiometric anomalous associated with the granitic pegmatites,which are intruded in the granitic host *** eU and eTh contents reached up to 316 and 1367 ppm,*** and thorium occurrences in the investigated granitic pegmatites are related to magmatic(syngenetic)ori

关键词： Geochemistry Gabal Um Lassaf-Abu Dob-Um Atelia-Kadabora-Kab El Rakeb area(LDAKK) Uranium REE Egypt

Virtual Keyboard:A Real-Time Hand Gesture Recognition-Based Character Input System Using LSTm and mediapipe Holistic

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Computer Systems Science & Engineering 2024年第2期48卷 555-570页

作者： Bijon mallik md Abdur Rahim Abu saleh musa miah Keun Soo Yun Jungpil Shin Department of Computer Science and Engineering Pabna University of Science and TechnologyPabna6600Bangladesh School of Computer Science and Engineering The University of AizuAizuwakamatsuFukushima965-8580Japan School of Computer and Information Technology Ulsan CollegeDong-guUlsan44610South Korea

In the digital age,non-touch communication technologies are reshaping human-device interactions and raising security concerns.A major challenge in current technology is the misinterpretation of gestures by sensors and cameras,often caused by environmental *** issue has spurred the need for advanced data processing methods to achieve more accurate gesture recognition and *** study presents a novel virtual keyboard allowing character input via distinct hand gestures,focusing on two key aspects:hand gesture recognition and character input *** developed a novel model with LSTm and fully connected layers for enhanced sequential data processing and hand gesture *** also integrated CNN,max-pooling,and dropout layers for improved spatial feature *** model architecture processes both temporal and spatial aspects of hand gestures,using LSTm to extract complex patterns from frame sequences for a comprehensive understanding of input *** unique dataset,essential for training the model,includes 1,662 landmarks from dynamic hand gestures,33 postures,and 468 face landmarks,all captured in real-time using advanced pose *** model demonstrated high accuracy,achieving 98.52%in hand gesture recognition and over 97%in character input across different *** excellent performance in real-time testing underlines its practicality and effectiveness,marking a significant advancement in enhancing human-device interactions in the digital age.

关键词： Hand gesture recognition m.P.holistic open CV virtual keyboard LSTm human-computer interaction

Various Organic Nutrient Sources in Combinations with Inorganic Fertilizers Influence the Yield and Quality of Sweet Corn(Zea mays ***)in New Alluvial Soils of West Bengal,India

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Phyton-International Journal of Experimental Botany 2024年第4期93卷 763-776页

作者： Anindita Das Kanu murmu Biplab mitra Pintoo Bandopadhyay Ritesh Kundu moupiya Roy saleh Alfarraj mohammad Javed Ansari marian Brestic Akbar Hossain Department of Agronomy School of Agricultural SciencesJIS UniversityKalyaniNadiaWest Bengal741235India Department of Agronomy Bidhan Chandra Krishi ViswavidyalayaMohanpurWest Bengal741252India Department of Agronomy Uttar Banga Krishi ViswavidyalayaCoochbeharWest Bengal736101India Office of The Assistant Director of Agriculture Gosaba BlockArampurSouth 24 ParganasWest Bengal743370India Department of Agricultural Statistics Bidhan Chandra Krishi ViswavidyalayaMohanpurWest Bengal741252India Zoology Department College of ScienceKing Saud UniversityRiyadh11451Saudi Arabia Department of Botany Hindu College Moradabad(Mahatma Jyotiba Phule Rohilkhand UniversityBareilly)MoradabadUttar Pradesh244001India Institute of Plant and Environmental Sciences Slovak University of AgricultureTr.A.Hlinku 2Nitra94901Slovak Division of Soil Science Bangladesh Wheat and Maize Research InstituteDinajpur5200Bangladesh

Nutrient management plays a crucial role in the yield and quality of sweet corn.A field experiment was conducted in consecutive two kharif seasons in 2018 and 2019 to investigate the effect of various organic sources of nutrients in combination with inorganic sources on the yield and quality of sweet corn under new alluvial soils of West Bengal,*** were:T_(1):Control(without fertilizers);T_(2):100%recommended dose(RDF)of chemical fertilizers(CF)(RDF CF_(100%));T_(3):100%recommended dose of N(RDN)through vermicompost(VC)(RDN VC_(100%));T_(4):50 RDN through CF+50%RDN through VC(RDN CF_(50%)+RDN VC50%);T_(5):50%RDF through CF+50%RDN through organic source(OS)1,Soligro(Ascophyllum nodosum)granular(RDN CF_(50%)+RDN OS_(150%));T6:50%RDN through CF+50%RDN through OS 2,Bioenzyme(liquid)(RDN CF_(50%)+RDN OS250%);T7:50%RDN through CF+50%RDN through OS 3,Opteine(Ascophyllum nodosum)filtrate[RDN CF_(50%)+RDN OS350%];T8:50%RDN through VC+50%RDF through OS 1,Soligro(Ascophyllum nodosum)granular(RDN VC50%+RDN OS_(150%)).The OS of fertilizers were VC,SoliGro Gr(OS1)(Ascophyllum nodosum),Bioenzyme liquid(OS2),and Opteine(Ascophyllum nodosum)filtrate(OS3).The inorganic source was traditional CF applied at the RDF(150:75:75 kg ha^(−1) of N:P2O5:K2O).The VC was used to supply 100%RDN as one source or 50%RDN when combined with CF or *** fruit yield(10.75 and 10.79 t ha^(−1) in 2018 and 2019,respectively)was recorded when RDF was substituted through CF only,being statistically at par with 50%CF+50%VC on a nitrogen equivalent basis(9.92 and 10.00 t ha^(−1) in 2018 and 2019,respectively)and 100%VC(8.22 and 8.32 t ha^(−1) in 2018 and 2019,respectively).Compared to chemical sources of nutrients,VC-based treatments produced a larger percentage of large-size cob(>25 cm).The 100%VC increased antioxidant(8.35 and 8.45 mg g^(−1)),carotenoid(0.59 and 0.61 mg/100 g),and phenol(55.06 and 55.02 mg 100 g^(−1))content compared with its 50%dose in combination with other *** s

关键词： Biostimulants Ascophyllum nodosum crop quality crop yield sweet corn