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Effect of ion and electron beam irradiation on surface morphology and optical properties of PVA

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Nuclear Science and Techniques 2015年第6期26卷 74-79页

作者： H.m.Eyssa m.Osman S.A.Kandil m.m.abdelrahman Radiation Chemistry Department National Center for Radiation Research and Technology Atomic Energy Authority (second research reactor) Cyclotron Project Nuclear Research Center Egypitation Atomic Energy Authority Accelerators & Ion Sources Dept. Nuclear Research CenterAtomic Energy Authority

Polyvinyl alcohol(PVA) is a well-known friendly polymer for paper-making, textiles, and a variety of coatings, biomedical applications such as artificial pancreas, synthetic vitreous body, wound dressing, artificial skin,and cardiovascular device. In this paper, ion/electron beam is employed to get insight into the irradiation effect on surface morphology and optical properties of PVA polymer. UV-Vis spectra are recorded to investigate the effect of induced defects on the optical band gap and the formed carbon clusters size. Scanning electron microscopy(SEm) is used to relate and investigate surface morphology and optical properties of the target polymer with different doses(15, 30 and 60 min). Also, PVA polymer is subjected to theoretical studies by using semi-empirical Pm7 quantum chemical method.

关键词：电子束辐照光学性质表面形貌聚乙烯醇离子扫描电子显微镜乙烯醇聚合物紫外-可见光谱

Simulation of ion beam extraction and focusing system

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Chinese Physics C 2011年第1期35卷 83-87页

作者： B.A.Soliman m.m.abdelrahman A.G.Helal F.W.Abdelsalam Accelerators & Ion Sources Department Nuclear Research CenterEgyptian Atomic Energy Authority P.O.Box:13759 InchasAtomic EnergyCairoEgypt

The characteristics of ion beam extraction and focused to a volume as small as possible were investigated with the aid of computer code SImION 3D version 7. This has been used to evaluate the extraction characteristics （accel-decel system） to generate an ion beam with low beam emittance and high brightness. The simulation process can provide a good study for optimizing the extraction and focusing system of the ion beam without any losses and transported to the required target. Also, a study of a simulation model for the extraction system of the ion source was used to describe the possible plasma boundary curvatures during the ion extraction that may be affected by the change in an extraction potential with a constant plasma density meniscus.

关键词： ion beam emittance plasma meniscus space charge argon ion trajectories

maternal body condition during latepregnancy is associated with in utero development and neonatal growth of Holstein calves

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Journal of Animal Science and Biotechnology 2021年第3期12卷 984-994页

作者： A.S.Alharthi D.N.Coleman I.A.Alhidary m.m.abdelrahman E.Trevisi J.J.Loor Department of Animal Production College of Food and Agriculture SciencesKing Saud UniversityRiyadh 11451Saudi Arabia Department of Animal Sciences and Division of Nutritional Sciences University of IllinoisUrbanaIL 61801USA Department of Animal Sciences Food and Nutrition(DIANA)Faculty of AgricultureFood and Environmental ScienceUniversitàCattolica del Sacro Cuore29122 PiacenzaItaly

Background:Nutritional management in the dry period can alter body condition score(BCS)in dairy cows,a subjective measure of body *** such,differences in BCS during late-pregnancy not only mirror nutrient utilization by fat depots,but also can play important roles on the metabolic and hormonal *** investigated the association between cow BCS during late-pregnancy on developmental parameters and blood variables of neonatal ***-nine multiparous Holstein cows were retrospectively divided by prepartal BCS into normal BCS≤3.25(NormBCS;3.02±0.17,n=30)or high BCS≥3.75(HighBCS;3.83±0.15,n=19)*** samples were collected from cows at−10 d relative to *** weight,hip and wither height,hip width and body length were measured at birth and weekly through weaning(42 d of age)and until 9 weeks of *** blood samples were collected from the jugular vein at birth(before receiving colostrum,0 d),24 h after first colostrum and at 7,21,42 and 50 d of *** data were subjected to ANOVA using the mixed procedure of *** statistical model included day,BCS,and their ***:Dry matter intake(kg/d or%of body weight)during the last 4 weeks of pregnancy was lower(P≤0.06)in HighBCS *** concentrations of fatty acids,ceruloplasmin,and nitric oxide were greater overall(Pms with *** addition,plasma concentrations of fatty acids,albumin and urea(Pmaintained a lower postnatal body weight(P=0.04),hip and wither height,hip width,and body length,there was no difference(P>0.05)in daily starter intake and average daily gain due to maternal ***:Overall,results highlight an association between BCS during late-gestation on in utero calf development and postna

关键词： metabolism Neonate Nutritional programming Transition cow

Study of Plasma and Ion Beam Sputtering Processes

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Journal of Physical Science and Application 2015年第2期5卷 128-142页

作者： m.m.abdelrahman Accelerators and 1on Sources Department Nuclear Research Center Atomic Energy Authority 13759 lnchas Atomic Energy CairoEgypt

The effects of plasma （ions, electrons） and other energetic particles are now widely used for substrate cleaning as well as to assist and control thin film growth and various applications. In this work, historical review of the plasma and its various types are given and described. Different types of gas discharge and plasma production are also discussed in detail. Furthermore, technique of ion beam extraction from a plasma source for sputtering process by using a suitable electrode is carefully studied and given. In further consequence, a general review about the physics and mechanism of sputtering processes is studied. Different types of sputtering techniques are investigated and clarified. Theoretical treatment for determination of sputtering yield for low and high atomic species elements as a function of energy from 100 to 5,000 eV are studied and discussed. Finally, various applications of plasma-and-ion beam sputtering will also be mentioned and discussed.

关键词： Plasma ion sputtering gas mixing electron injection.

Explainable AI-Based DDoS Attacks Classification Using Deep Transfer Learning

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Computers, materials & Continua 2024年第9期80卷 3785-3802页

作者： Ahmad Alzu’bi Amjad Albashayreh abdelrahman Abuarqoub mai A.m.Alfawair Department of Computer Science Jordan University of Science and TechnologyIrbid22110Jordan Department of Computer Science The University of JordanAmman11942Jordan Cardiff School of Technologies Cardiff Metropolitan UniversityCardiffCF52YBUK Prince Abdullah bin Ghazi Faculty of Information and Communication Technology Al-Balqa Applied UniversitySalt19117Jordan

In the era of the Internet of Things(IoT),the proliferation of connected devices has raised security concerns,increasing the risk of intrusions into diverse *** the convenience and efficiency offered by IoT technology,the growing number of IoT devices escalates the likelihood of attacks,emphasizing the need for robust security tools to automatically detect and explain *** paper introduces a deep learning methodology for detecting and classifying distributed denial of service(DDoS)attacks,addressing a significant security concern within IoT *** effective procedure of deep transfer learning is applied to utilize deep learning backbones,which is then evaluated on two benchmarking datasets of DDoS attacks in terms of accuracy and time *** leveraging several deep architectures,the study conducts thorough binary and multiclass experiments,each varying in the complexity of classifying attack types and demonstrating real-world ***,this study employs an explainable artificial intelligence(XAI)AI technique to elucidate the contribution of extracted features in the process of attack *** experimental results demonstrate the effectiveness of the proposed method,achieving a recall of 99.39%by the XAI bidirectional long short-term memory(XAI-BiLSTm)model.

关键词： DDoS attack classification deep learning explainable AI cybersecurity

Unraveling the nature of sensing in electrostatic mEmS gas sensors

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microsystems & Nanoengineering 2024年第3期10卷 109-117页

作者： Yasser S.Shama Sasan Rahmanian Hamza mouharrar Rana abdelrahman Alaaeldin Elhady Eihab m.Abdel-Rahman Systems Design Engineering University of Waterloo200 University Ave WWaterloo N2L 3G1 ONCanada mechanical Engineering Benha Faculty of EngineeringBenha UniversityBenha 13511Egypt

This paper investigates the fundamental sensing mechanism of electrostatic mEmS gas *** compares among the responsivities of a set of mEmS isopropanol sensors before and after functionalization,and in the presence and absence of electrostatic fields when operated in static and dynamic detection *** the static mode,we found that the sensors do not exhibit a measurable change in displacement due to added *** the other hand,bare sensors showed a clear change in displacement in response to isopropanol *** the dynamic mode,functionalized sensors showed a measurable frequency shift due to the added mass of isopropanol *** the presence of strong electrostatic fields,the measured frequency shift was found to be threefold larger than that in their absence in response to the same concentration of isopropanol *** enhanced responsivity of dynamic detection allows the sensors to measure the vapor mass captured by the functional material,which is not the case for static *** detection of isopropanol by bare sensors in static mode shows that change in the medium permittivity is the primary sensing *** enhanced responsivity of dynamic mode sensors when operated in strong electrostatic fields shows that their sensing mechanism is a combination of a weaker added mass effect and a stronger permittivity *** findings show that electrostatic mEmS gas sensors are independent of the direction of the gravitational field and are,thus,robust to changes in *** is erroneous to refer to them as‘gravimetric’sensors.

关键词： mechanism electrostatic measurable

Dysprosium oxide,alumina,and graphene oxide reinforced polycaprolactone thin films:Thermal stability,morphology,and cell viability

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Journal of Rare Earths 2024年第7期42卷 1337-1343,I0005页

作者： mohamed Tharwat Elabbasy mohamed R.Atteya mai A.Samak mousa abdelrahman Tahani Almahmoud m.A.El-morsy A.A.menazea m.F.H.Abd El-Kader Department of Public Health College of Public Health and Health InformaticsUniversity of Ha'ilHa'il2440Saudi Arabia Food Control Department Faculty of Veterinary MedicineZagazig UniversityZagazig44519Egypt Department of Physical Therapy College of Applied Medical SciencesUniversity of Ha'ilHa'ilSaudi Arabia Department of Histology and Cell Biology Faculty of MedicineZagazig UniversityZagazig44519Egypt College of Nursing University of Ha'ilHa'ilSaudi Arabia College of Science and Humanities in Al-Kharj Physics DepartmentPlasma Technology and Material Science UnitPrince Sattam Bin Abdulaziz UniversityAl-kharj11942Saudi Arabia Physics Department Faculty of ScienceUniversity of DamiettaNew Damietta34517Egypt Spectroscopy Department Physics Research InstituteNational Research CentreDokki12622GizaEgypt Biophysics Department Faculty of ScienceCairo UniversityGizaEgypt

Developing a biomaterial for wound healing applications is still a ***,dysprosium oxide(Dy_(2)O_(3)),aluminum oxide(Al_(2)O_(3)),and graphene oxide(GO)were embedded in cast films based on polycaprolactone(PCL)to be examined for wound dressing *** techniques were used to characterize the fabricated films including X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),Raman,and scanning electron microscopy(SEm),besides their biological *** thermogravimetric analysis(TGA)exhibits high thermal stability as the scaffold weight decreases slightly to 98.6%after raising the temperature from room temperature to 280℃.The cell viability was investigated and it is shown that the viable cells grow up to approximately 93%at 75μg/***,the cell attachment shows excellent behavior as the cells attach on most of the surface of the modified PCL which shows high biocompatibility.

关键词： Wound healing Polycaprolactone Dy_(2)O_(3) Al_(2)O_(3) Biocompatible Rare earths

Influence of cerium ions on structure-dependent magnetic properties of Ba-Sr m-type hexaferrite nanocrystals

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Journal of Rare Earths 2024年第2期42卷 364-372,I0005页

作者： Ram A.Pawar Sunil m.Patange P.m.Dighe Sher Singh meena Abdullah GAl-Sehemi mehboobali Pannipara Santosh S.Jadhav Department of Physics ArtsCommerce and Science CollegeAhmednagar413711MaharashtraIndia Department of Physics Shri Krishna MahavidyalayaGunjotiDistOsmanabad413606MaharashtraIndia Padmashri Vikhe Patil College of Arts Science and CommercePravaranagarA/P.Loni(Kd)Tal.RahataDistAhmednagar413713MaharashtraIndia Solid State Physics Division Bhabha Atomic Research CentreMumbai400085MaharashtraIndia Department of Chemistry King Khalid UniversityAbha61413Saudi Arabia Department of Physics D.S.M's ArtsCommerce and Science CollegeJintur431509MaharashtraIndia

The present study is a systematic effort to investigate the structure-sensitive magnetic parameters of Ce^(3+) substituted Ba-Sr hexaferrite nanocrystals chemically formulated as Ba_(0.5)Sr_(0.5)Ce_(x)Fe_(12-x)O_(19) where x=0.0-0.2 with Δx=*** hexaferrite powders were prepared using the sol-gel self-ignition route and structurally characterized by means of powder X-ray diffraction and Fourier transform infrared *** creation of the m-type hexaferrite phase within the synthesized samples was revealed from the Rietveld refinement of the X-ray *** occurrence of a secondary phase of CeO_(2) was revealed within the hexaferrites for the substitution,x> *** refined X-ray diffraction data were utilized to compute the lattice parameters,X-ray density,and lattice parameter *** crystal structure plotted from the refined XRD data reveals the occupancy of the ions at different lattice *** XPS data of the hexaferrite were analyzed to confirm the oxidation states of the constituent *** nanocrystalline nature of the hexaferrites was revealed from the crystallite sizes calculated using Scherer's *** analysis of FTIR spectra confirms that only a fraction of Ce^(3+)accommodated in the lattice and the remaining Ce content reside in the form of the CeO_(2) *** morphology of the hexaferrites was analyzed from the FESEm profiles of the ferrite *** magnetic behavior study was performed by analyzing the Curie temperature,hysteresis loops,and hyperfine interactions by means of susceptibility,V.S.m,and mossbauer spectroscopy,*** hexaferrites with increasing coercivity,decreasing saturation magnetization,and decreasing Curie temperature are reported in the *** substituted Ce^(3+)ions inhibit the grain growth and create lattice imperfections giving rise to hexaferrites with tuned magnetic parameters suitable for different applications.

关键词： Ba-Sr hexaferrite Ce^(3+)substitution XPS Saturation magnetization Coercivity m?ssbauer spectroscopy

Frequency-dependent viscoelasticity effects on the wave attenuation performance of multi-layered periodic foundations

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 407-424页

作者： m.SAFI m.VAKILIFARD m.J.mAHmOODI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of mechanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are numerically examined for their responses to longitudinal and transverse modes in the time and frequency *** different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,comprising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber materials,respectively,are taken into ***,the viscoelasticity behavior of the rubber is modeled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss *** the extraction of the complex dispersion curves and the identification of the band gaps(BGs),the simulations of wave transmission in the time and frequency domains are performed using the COmSOL *** parametric studies evaluate the effects of the rubber viscoelasticity models on the dispersion curves and the wave transmission for the longitudinal and transverse *** results show that considering the rubber viscoelasticity enhances the wave attenuation ***,the transverse-mode damping is more sensitive to the viscoelasticity model than its longitudinal *** 6-layer unit-cell LPF exhibits the lowest BG,ranging from 4.8 Hz to 6.5 Hz.

关键词： layered metamaterial periodic foundation complex dispersion curve wave transmission diagram