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National science Review 2024年第3期11卷 150-158页

作者： Kun Li Jun Zhang David m.Bell Tiantian Wang Houssni Lamkaddam Tianqu Cui Lu Qi mihnea surdu Dongyu Wang Lin Du Imad el Haddad Jay G.slowik Andre s.H.Prevot Environment Research Institute Shandong University Laboratory of Atmospheric Chemistry Paul Scherrer Institute

Organic vapors from biomass burning are a major source of secondary organic aerosols(sOAs). Previous smog chamber studies found that the sOA contributors in biomass-burning emissions are mainly volatile organic compounds(VOCs). While intermediate volatility organic compounds(IVOCs) are efficient sOA precursors and contribute a considerable fraction of biomass-burning emissions, their contribution to sOA formation has not been directly observed. Here, by deploying a newly-developed oxidation flow reactor to study sOA formation from wood burning, we find that IVOCs can contribute ～70% of the formed sOA, i.e.>2 times more than VOCs. This previously missing sOA fraction is interpreted to be due to the high wall losses of semi-volatile oxidation products of IVOCs in smog chambers. The finding in this study reveals that sOA production from biomass burning is much higher than previously thought, and highlights the urgent need for more research on the IVOCs from biomass burning and potentially other emission sources.

关键词： atmospheric chemistry biomass burning secondary organic aerosol intermediate volatility organic compounds

Enhancement of coercivity,permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites for memory and high frequency devices

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Journal of Rare Earths 2024年第6期42卷 1128-1135,I0005页

作者： I.sardar m.D.Hossain m.s.sikder m.N.I.Khan m.R.Rahman Physics Discipline Khulna UniversityKhulna9208Bangladesh Department of Physics Khulna University of Engineering&TechnologyKhulna9203Bangladesh Department ofComputer science and Engineering Northern University of Business&Technology KhulnaKhulna9100Bangladesh material science Division Atomic Energy CentreDhaka1000Bangladesh

spinel cubic ferrites have huge applications in me mory and high frequency *** the improvement of these modern devices,the magnetic coercivity,permeability,and dielectric properties of a ferrite are the important *** article focuses on improving the magnetic coercivity,magnetic permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites,where x=0.00,0.06,and *** X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),field emission scanning electron microscopy(FEsEm),energy dispersive X-ray(EDX),vibrating sample magnetometer(Vsm),and an impedance analyzer were used to characterize the structural,magnetic,and dielectric properties of the *** XRD patterns indicate the formation of spinel cubic structure of the samples with a secondary peak(EuFeO_(3))for Eu doped *** densities and porosities of the samples follow an inverse trend,where the doped samples’lattice parameters are increased with the increment of rare earth Eu *** FTIR analysis also proves the spinel cubic phase of the *** average grain size of the ferrites is obtained via FEsEm images,and it is increased from 121 to 198 *** analysis confirms that doping of the Eu content also changes other hysteresis loop properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ***,the coercivity of the Eu doped samples is greater than that of the mother alloy(x=0.00).The EDX study shows that there is no impurity contamination in the *** permeability and dielectric measurements show an improved quality factor of the Eu-doped samples with low magnetic and dielectric *** dependent resistivity and impedance analysis also show the improved *** the observed properties of the samples,all the investigated ferrites might be strong candidates for potential applications in memory devices,magnetic sensors,and high frequency applications.

关键词： Ferrites Raree arths Coercivity Permeability EDX Resistivity

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standardization of meibomian gland dysfunction in an Egyptian population sample using a non-contact meibography technique

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 61-65页

作者： Ahmed mohamed Karara Zeinab el-sanabary mostafa Ali el-Helw Tamer Ahmed macky mohamad Amr salah Eddin Abdelhakim Department of Ophthalmology Kasr Al-Ainy HospitalCairo UniversityCairo 11431Egypt

AIm:To develop normative data for meibomian gland dysfunction(mGD)parameters,using non-contact meibography technique of sirius Costruzione strumenti Oftalmici(CsO)machine,in an Egyptian population ***:Observational,cross-sectional,analytic study,in which 104 Egyptian volunteers were *** upper lids were examined,using“sirius CsO”*** eyelid was given a degree of meibomian gland loss(mGL),which was calculated by the software of the ***:mean percentage mGL in right upper lid was of 30.9%±12.6%,and that of left upper lid was 32.6%±11.8%.Thirty-four volunteers(32.7%)had first-degree mGL in their right upper lid,and 67.3%had second-degree *** volunteer(1%)had zero-degree mGL in left upper lid,28(26.9%)had first-degree loss,and 75(72.1%)had second-degree *** of mGL in right upper eyelid was not related to age,but degree of mGL in left upper eyelid increased with *** was statistically significant difference between both genders for degree of mGL in right eye(P=0.036)and in left eye(P=0.027).CONCLUsION:Noncontact meibography is a useful non-invasive tool for diagnosing *** is diagnosed in 100%of apparently normal individuals;26.9%-32.7%of which have first-degree mGL,and 67.3%-72.1%have second-degree mGL.

关键词： Egyptian population meibomian gland dysfunction non-contact meibography standardization upper lid

Portal vein tumor thrombosis in hepatocellular carcinoma patients: Is it the end?

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Liver Research 2024年第3期8卷 141-151页

作者： Walaa Abdelhamed Hend shousha mohamed el-Kassas Endemic medicine Department Sohag UniversitySohagEgypt Endemic medicine Department Faculty of MedicineCairo UniversityCairoEgypt Endemic medicine Department Faculty of MedicineHelwan UniversityCairoEgypt Liver Disease Research Center College of MedicineKing Saud UniversityRiyadhSaudi Arabia

Hepatocellular carcinoma(HCC)is the sixth most prevalent form of cancer globally and the third leading cause of cancer-related *** incidence of portal vein tumor thrombosis(PVTT)in HCC patients is 21%at one year and 46%at three *** presence of PVTT has consistently been associated with a poor prognosis for HCC patients over the past ***,HCC prognosis is influenced not only by the presence of PVTT but also by the degree or extent of ***,there is a lack of global consensus or established protocols regarding the optimal management of HCC with associated *** Barcelona Clinic for Liver Cancer classifies HCC patients with PVTT as stage C,indicating an advanced stage,and limiting treatment recommendations for these patients to systemic *** recent years,there has been an increase in the availability of therapeutic options for HCC patients with *** modalities include systemic therapy,transarterial chemoembolization,surgical resection,stereotactic body radiotherapy,transarterial radioembolization,and liver *** ideal therapy for each patient necessitates a multidisciplinary *** review article presents the latest updates in managing HCC patients with PVTT.

关键词： Hepatocellular carcinoma(HCC) Portal vein tumor thrombosis(PVTT) staging systemic therapies Locoregional treatment Immunotherapy

Wave Reflection by Rectangular Breakwaters for Coastal Protection

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Fluid Dynamics & materials Processing 2024年第3期20卷 579-593页

作者： Hasna Akarni Hamza mabchour Laila el Aarabi soumia mordane Laboratory of Polymer Physics Mechanical Sciences and MaterialsFaculty of Sciences Ben M’SikHassan II University of CasablancaCasablanca20670Morocco

In this study,we focus on the numerical modelling of the interaction between waves and submerged structures in the presence of a uniform flow *** the same and opposite senses of wave propagation are *** main objective is an understanding of the effect of the current and various geometrical parameters on the reflection *** wave used in the study is based on potential theory,and the submerged structures consist of two rectangular breakwaters positioned at a fixed distance from each other and attached to the bottom of a wave *** numerical modeling approach employed in this work relies on the Boundary element method(BEm).The results are compared with experimental data to validate the *** findings of the study demonstrate that the double rectangular breakwater configuration exhibits superior wave attenuation abilities if compared to a single rectangular breakwater,particularly at low ***,the study reveals that wave mitigation is more pronounced when the current and wave propagation are coplanar,whereas it is less effective in the case of opposing current.

关键词： Wave current breakwaters Boundary element method(BEm) reflection coefficient

A Hybrid Cybersecurity Algorithm for Digital Image Transmission over Advanced Communication Channel models

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Computers, materials & Continua 2024年第4期79卷 201-241页

作者： Naglaa F.soliman Fatma E.Fadl-Allah Walid el-shafai mahmoud I.Aly maali Alabdulhafith Fathi E.Abd el-samie Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of electronics and Communications Faculty of EngineeringZagazig UniversityZagazig44519Egypt security Engineering Lab Computer Science DepartmentPrince Sultan UniversityRiyadh11586Saudi Arabia Department of electronics and electrical Communications Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt

The efficient transmission of images,which plays a large role inwireless communication systems,poses a significant challenge in the growth of multimedia ***-quality images require well-tuned communication *** single Carrier Frequency Division multiple Access(sC-FDmA)is adopted for broadband wireless communications,because of its low sensitivity to carrier frequency offsets and low Peak-to-Average Power Ratio(PAPR).Data transmission through open-channel networks requires much concentration on security,reliability,and *** data need a space away fromunauthorized access,modification,or *** requirements are to be fulfilled by digital image watermarking and *** paper ismainly concerned with secure image communication over the wireless sC-FDmA systemas an adopted communication *** introduces a robust image communication framework over sC-FDmA that comprises digital image watermarking and encryption to improve image security,while maintaining a high-quality reconstruction of images at the receiver *** proposed framework allows image watermarking based on the Discrete Cosine Transform(DCT)merged with the singular Value Decomposition(sVD)in the so-called DCT-sVD *** addition,image encryption is implemented based on chaos and DNA *** encrypted watermarked images are then transmitted through the wireless sC-FDmA *** linearminimummean square Error(mmsE)equalizer is investigated in this paper to mitigate the effect of channel fading and noise on the transmitted *** subcarrier mapping schemes,namely localized and interleaved schemes,are compared in this *** study depends on different channelmodels,namely PedestrianAandVehicularA,with a modulation technique namedQuadratureAmplitude modulation(QAm).Extensive simulation experiments are conducted and introduced in this paper for efficient transmission of encrypted watermarked *** addition,different variants of sC-FDmA bas

关键词： Cybersecurity applications image transmission channel models modulation techniques watermarking and encryption

Experimental design of paraffin/methylated melamine-formaldehyde microencapsulated composite phase change material and the application in battery thermal management system

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Journal of materials science & Technology 2024年第2期169卷 124-136页

作者： Que Huang silong Wang Jichun He Dengji Xu safaa NAbdou mohamed mIbrahim shiqi sun Yanjun Chen Handong Li Ben Bin Xu Changcheng Liu Zeinhom m.el-Bahy Zhanhu Guo school of Environment and safety Engineering North University of ChinaTaiyuan 030051China Institute of Advanced Energy materials and systems North University of ChinaTaiyuan 030051China school of Resources and safety Engineering Central South UniversityChangsha 410010China school of medical and BioInformation Engineering Northeastern UniversityShenyang 110819China Department of Chemistry Khurmah University CollegeTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia mechanical and Construction Engineering Faculty of Engineering and EnvironmentNorthumbria UniversityNewcastle Upon Tyne NE18STUK College of materials science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Department of Chemistry Faculty of ScienceAl-Azhar UniversityNasr City 11884CairoEgypt

In order to maintain the optimal operating temperature of the battery surface and meet the demand for thermal storage technology,battery thermal management system based on phase change materials has attracted increasing *** this work,a kind of core-shell structured microcapsule was synthesized by an in-situ polymerization,where paraffin was used as the core,while methanol was applied to mod-ify the melamine-formaldehyde shell to reduce toxicity and improve thermal ***,three different types of heat conductive fillers with the same content of 10 wt.%,i.e.,nano-Al_(2)O_(3),nano-ZnO and carbon nanotubes were added,generating *** microcapsules were uniform,and were not affected by the thermal fillers,which were evenly dispersed *** composite sample with carbon nanotubes(10 wt.%)showed the highest thermal conductivity of 0.50 W/(m K)and latent heat of 139.64 J/***,according to the leakage testing and battery charge/discharge experiments,compared with Al_(2)O_(3)and ZnO,the addition of carbon nanotubes remarkably enhances the heat storage ability as latent heat from 126.98 J/g for the prepared sample with Al_(2)O_(3)and 125.86 J/g for the one with ZnO,then to 139.64 J/g,as well as dissipation performance as a cooling effect by decreasing the sur-face temperature of battery from 2%to 12%of microcapsule,composite sample with carbon nanotubes presents a broad application prospect in battery thermal management system and energy storage field.

关键词： microcapsule Phase change material Battery Carbon nanotube safety

Investigation of microstructure, microhardness and Thermal Properties of Ag-In Intermetallic Alloys Prepared by Vacuum Arc meltings

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Journal of Wuhan University of Technology(materials science) 2024年第1期39卷 182-187页

作者： ÇelİK Erçevik ATA EsENER Pınar ÖZTÜRK Esra AKsÖZ sezen Nevşehir HacıBektaşVeli University Department of Physics50300NevşehirTurkey Erciyes University Graduate School of Natural and Applied Sciences38039KayseriTurkey Kocaeli University Department of Physics41380KocaeliTurkey

Ag-In intermetallic alloys were produced by using vacuum arc furnace. Differential scanning Calorimetry(DsC) and Energy Dispersive X-Ray spectrometry(EDX) were used to determine the thermal properties and chemical composition of the phases respectively. microhardness values of Ag-In intermetallics were calculated with Vickers hardness measurement method. According to the experimental results, Ag-34 wt%In intermetallic system generated the best results of energy saving and storage compared to other intermetallic systems. Also from the microhardness results, it was observed that intermetallic alloys were harder than pure silver and Ag-26 wt%In system had the highest microhardness value with 143.45 kg/mm^(2).

关键词： thermal properties microstructure characterization microhardness alloys material characterization

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Analysis of the Impact of the Blazhko Effect Both on the Van Hoof Effect and Radial Velocity Amplitude in the star RR Lyr

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Research in Astronomy and Astrophysics 2024年第6期24卷 253-272页

作者： Y.el jariri F.L.sefyani A.Benhida Z.Benkhaldoun K.Kolenberg K.Chafouai A.Habib m.sabil Observatoire de l'Oukaimeden LPHEAFSSMUniversitéCadi AyyadMarrakech2390Morocco Observatoire de l'Oukaimeden LPHEAFSTGUniversitéCadi AyyadMarrakech549Morocco Département de physique Universitéd'Anvers Avenue Groenenborger 171Anvers2020Belgium LICPm ENSA-BMUniversitéSultan Moulay SlimaneBeni-Mellal23020Morocco

The Van Hoof effect is a phase shift existing between the radial velocity curves of hydrogen and metallic lines within the atmosphere of pulsating *** this article,we present a study of this phenomenon through the spectra of the brightest pulsating star RR Lyr of RR Lyrae stars recorded for 22 *** based ourselves,on the one hand,on 1268 spectra(41 nights of observation)recorded between the years 1994 and 1997 at the Observatory of Haute Provence(OHP,France)previously observed by Chadid and Gillet,and on the other hand on 1569 spectra(46nights of observation)recorded at our Oukaimeden Observatory(morocco)between 2015 and *** this study,we have detected information on atmospheric dynamics that had not previously been ***,the Van Hoof effect which results in a clear correlation between the radial velocities of hydrogen and those of the metallic lines has been observed and analyzed at different Blazhko phases.A correlation between the radial velocities of different metallic lines located in the lower atmosphere has been observed as *** the first time,we were able to show that the amplitude of the radial velocity curves deduced from the lines of hydrogen and that of FeⅡ(λ4923.921?)increases toward the minimum of the Blazhko cycle and decreases toward the maximum of the same Blazhko ***,we found that the Van Hoof effect is also modulated by the Blazhko ***,toward the minimum of the Blazhko cycle the Van Hoof effect is more visible and at the maximum of the Blazhko cycle,this effect is *** also observed the temporal evolution of the amplitudes of the radial velocities of the lower and upper *** observed over a long time,we can interpret it as a function of the Blazhko phases.

关键词： stars:atmospheres stars:variables:RR Lyrae shock waves techniques:spectroscopic techniques:radial velocities stars:individual(RR Lyr)

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suitability of sDN and mEC to facilitate digital twin communication over LTE-A

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Digital Communications and Networks 2024年第2期10卷 347-354页

作者： Hikmat Adhami mohammad Alja’afreh mohamed Hoda Jiaqi Zhao Yong Zhou Abdulmotaleb el saddik mohamed bin Zayed University of Artificial Intelligence Masdar CityAbu DhabiUnited Arab Emirates school of Computer science and Technology China University of Mining and TechnologyXuzhou221116China school of electrical Engineering and Computer science University of OttawaOttawaONK1N 6N5Canada

Haptic is the modality that complements traditional multimedia,i.e.,audiovisual,to evolve the next wave of innovation at which the Internet data stream can be exchanged to enable remote skills and control *** will require ultra-low latency and ultra-high reliability to evolve the mobile experience into the era of Digital Twin and Tactile *** the 5th generation of mobile networks is not yet widely deployed,Long-Term Evolution(LTE-A)latency remains much higher than the 1 ms requirement for the Tactile Internet and therefore the Digital *** work investigates an interesting solution based on the incorporation of software-defined networking(sDN)and multi-access mobile Edge Computing(mEC)technologies in an LTE-A network,to deliver future multimedia applications over the Tactile Internet while overcoming the Qos *** network scenarios were designed and simulated using Riverbed modeler and the performance was evaluated using several time-related Key Performance Indicators(KPIs)such as throughput,End-2-End(E2E)delay,and *** best scenario possible is clearly the one integrating mEC and sDN approaches,where the overall delay,jitter,and throughput for haptics-attained 2 ms,0.01 ms,and 1000 packets per *** results obtained give clear evidence that the integration of,both sDN and mEC,in LTE-A indicates performance improvement,and fulfills the standard requirements in terms of the above KPIs,for realizing a Digital Twin/Tactile Internet-based system.

关键词： LTE-A 5G Digital twin Tactile Internet KPIs sDN mEC NFV Haptic