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Mineralogy and geochemistry of fine-grained Dahab stream sediments, Southeastern Sinai, Egypt: emphasis on the intergrowths of Fe–Ti oxides

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Acta Geochimica 2021年第6期40卷 871-894页

作者： Adel A.Surour Ahmed.M.A.El-Kammar ebtisam h.arafa hala M.Korany Petroleum and Mining Geology Faculty of SciencesGalala University43511 New Galala CityEgypt Department of Geology Faculty of ScienceCairo UniversityGiza 12613Egypt

Mineralogical and geochemical characteristics of stream sediments collected from 30 stations in the Dahab-Wadi Kid area(southeastern Sinai,Egypt)are *** studied sediments contain considerable amounts of heavy minerals,including abundant Fe–Ti oxides,with up to 25.94%index figure that measures the relative abundance of heavy minerals to light *** of the sediments and nature of Fe–Ti oxide intergrowths,in addition to some non-opaque heavy minerals,indicate multiple provenances with contributions from a variety of Neoproterozoic mafic to felsic *** amounts of heavy minerals are derived from schists that belong to the so-called Wadi Kid volcanosedimentary *** to the considerable contribution of the felsic intrusions represented by within-plate granites,the sediments are enriched in REE-bearing minerals(e.g.,monazite,cerianite,La-cerianite and allanite),V-bearing thorite,zircon,and a ZrO_(2) *** majority of Fe–Ti oxides are derived from the mafic intrusions,and they show evidence of pre-,syn-and post-depositional phases of alteration and formation of *** to the geochemical signature of the bulk silt fraction,there is remarkable enrichment of LREEs with distinct negative Eu anomaly,and this supports dominance of a provenance dominated by felsic intrusions(i.e.,the A-type within-plate granite and associated pegmatites).Also,the felsic provenance is responsible for slight abnormality of ∑PU+Th content(up to~37 ppm)and few anomalous samples bear uraniferous zircon and Ce-type *** present paper sheds light on the fertility of the Dahab stream sediments in some economic minerals for possible future exploitation,not for gold only,but for potential REEbearing minerals that are needed for a wide spectrum of modern technological industries.

关键词： Dahab stream sediments Silt fraction Fe-Ti oxides Textural variations Rees enrichment

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Effect of nutrition-related infodemics and social media on maternal experience: A nationwide survey in a low/middle income country

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World Journal of Clinical Pediatrics 2024年第1期13卷 93-106页

作者： Marwa M Zein Noha arafa Mortada h F El-Shabrawi Nehal Mohammed El-Koofy Department of Public health and Community Medicine Cairo UniversityCairo 515211Egypt Department of Pediatric Endocrinology and Diabetes Children's HospitalKasralainy Medical SchoolCairo UniversityCairo 515211Egypt Department of Pediatrics Cairo UniversityCairo 12411Egypt Department of Pediatrics The Children's HospitalCairo UniversityCairo 12411Egypt

BACKGROUND Undernutrition is a crucial cause of morbidity and mortality among children in low-or middle-income countries(LMICs).A better understanding of maternal general healthy nutrition knowledge,as well as misbeliefs,is highly essential,especially in such *** the current era of infodemics,it is very strenuous for mothers to select not only the right source for maternal nutrition information but the correct information as *** To assess maternal healthy nutritional knowledge and nutrition-related misbeliefs and misinformation in an LMIC,and to determine the sources of such information and their assessment *** This cross-sectional analytical observational study enrolled 5148 randomly selected Egyptian mothers who had one or more children less than 15 years *** data were collected through online questionnaire forms:One was for the general nutrition knowledge assessment,and the other was for the nutritional myth *** of information and ways of evaluating internet sources using the Currency,Relevance,Authority,Accuracy,and Purpose test were additionally *** The mean general nutrition knowledge score was 29±9,with a percent score of 70.8%±12.1%(total score:41).The median myth score was 9(interquartile range:6,12;total score:18).The primary sources of nutrition knowledge for the enrolled mothers were social media platforms(55%).half of the mothers managed information for currency and authority,except for considering the author's contact *** than 60%regularly checked information for accuracy and *** mothers with significant nutrition knowledge checked periodically for the author's contact information(P=0.012).The nutrition myth score was significantly lower among mothers who periodically checked the evidence of the information(P=0.016).Mothers dependent on their healthcare providers as the primary source of their general nutritional knowledge were less likely to hold myths by 13%(P=0.044).however,usi

关键词： Nutrition Infodemics Maternal knowledge Myth Low/middle income country

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Assessment of Radiological hazards of Sedimentary, Igneous and Sediments Natural Rocks

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World Journal of Nuclear Science and Technology 2024年第2期14卷 131-145页

作者： Wafaa arafa hala Mahmoud Eman Yousf Ashry Ashry Ibrahim Elaassy Ahmed Elsersy Faculty of Women Ain Shams University Cairo Egypt Nuclear Material Authority Cairo Egypt Faculty of Education Ain Shams University Cairo Egypt National Institute of Standard Giza Egypt

Gamma-ray spectroscopy based on a 100% efficiency hyper-pure germanium detector was used to evaluate the activity concentrations of 226Ra, 232Th, and 40K natural radionuclides in sedimentary, conglomerate, igneous and sedi-ments rock samples collected from four different locations in Eastern desert in Egypt. The obtained activity concentrations are used to evaluate the radi-ological hazards indices, absorbed dose rate, annual effective dose equivalent in air, radium equivalent, external and internal hazard index, radiation level index, annual gonadal dose equivalent, excess lifetime cancer risk and expo-sure rate. The results show that 1) the absorbed dose rate depends on the rock type, 2) the annual effective dose equivalent in air in 71% of sample below 20 mSvy-1 (permissible limit for workers), 3) the conglomerate rocks show low radioactivity level, 4) sedimentary rocks are rich in radium while igneous rocks are rich in thorium and the sediments rocks are rich in both radium and thorium.

关键词： Gamma Spectrometry Radiological hazard Indices NORM Sedimentary Conglomerate Igneous Sediments

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Low band gap frequencies and multiplexing properties in 1D and 2D mass spring structures

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Chinese Physics B 2016年第11期25卷 333-339页

作者： arafa h Aly Ahmed Mehaney Physics Department Faculty of Sciences Beni-Suef University

This study reports on the propagation of elastic waves in 1D and 2D mass spring *** analytical and computation model is presented for the 1D and 2D mass spring systems with different *** enhancement in the band gap values was obtained by modeling the structures to obtain low frequency band gaps at small ***,the evolution of the band gap as a function of mass value is *** attention is devoted to the local resonance property in frequency ranges within the gaps in the band structure for the corresponding infinite periodic lattice in the 1D and 2D mass spring system.A linear defect formed of a row of specific masses produces an elastic waveguide that transmits at the narrow pass band *** frequency of the waveguides can be selected by adjusting the mass and stiffness coefficients of the materials constituting the ***,we pay more attention to analyze the wave multiplexer and DE-multiplexer in the 2D mass spring *** show that two of these tunable waveguides with alternating materials can be employed to filter and separate specific frequencies from a broad band input *** presented simulation data is validated through comparison with the published research,and can be extended in the development of resonators and MEMS verification.

关键词： multiplexing waveguide tunable separate dimensions devoted verification stiffness validated infinite

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Peltier Coefficient and Photon-Assisted Tunnelling in Quantum Point Contact

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Chinese Physics Letters 2008年第12期25卷 4399-4401页

作者： arafa h. Aly Department of Physics Zaragoza University Zaragoza 50009 Spain Department of Physics Inha University 402-751 South Korea Department of Physics Faculty of Sciences Beni-Suef University Egypt

We present the Peltier coefficient and thermal transport in quantum point contact （QPC）, under the influence of external fields and different temperatures. Also we obtain the oscillations of the Peltier coefficient in external fields. Numerical calculations of the Peltier coefficient are performed at different applied voltages, amplitudes and temperatures. The obtained results are consistent with the experimental data in the literature.

关键词： field emission molybdenum dioxide enhancement factor

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A different approach for conformable fractional biochemical reaction–diffusion models

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Applied Mathematics(A Journal of Chinese Universities) 2020年第4期35卷 452-467页

作者： Anas arafa Department of Mathematics and Computer Science Faculty of SciencePort Said UniversityPort SaidEgypt

This paper attempts to shed light on three biochemical reaction-diffusion models:conformable fractional Brusselator,conformable fractional Schnakenberg,and conformable fractional *** is done using conformable residual power series(hence-form,CRPS)technique which has indeed,proved to be a useful tool for generating the ***,CRPS is an effective method of solving nonlinear fractional differential equations with greater accuracy and ease.

关键词： Brusselator model Schnakenberg model Gray-Scott model conformable fractional derivatives residual power series method

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Influence of temperature on the properties of one-dimensional piezoelectric phononic crystals

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Chinese Physics B 2018年第9期27卷 342-345页

作者： Ahmed Nagaty Ahmed Mehaney arafa h Aly Physics Department Faculty of Sciences Beni-Suef University

The current study investigates the influence of temperature on a one-dimensional piezoelectric phononic crystal using tunable resonant frequencies. Analytical and numerical examples are introduced to emphasize the influence of temperature on the piezoelectric phononic crystals. It was observed that the transmission spectrum of a one-dimensional phononic crystal containing a piezoelectric material（0.7 PMN-0.3 PT） can be changed drastically by an increase in *** resonant peak can be shifted toward high or low frequencies by an increase or decrease in temperature, ***, we deduced that temperature can exhibit a large tuning in the phononic band gaps and in the local resonant frequencies depending on the presence of a piezoelectric material. Such result can enhance the harvesting energy from piezoelectric materials, especially those that are confined in a phononic crystal.

关键词： phononic crystals resonant modes piezoelectric material thermal properties and temperature

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homotopy Analysis Method for Solving Biological Population Model

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Communications in Theoretical Physics 2011年第11期56卷 797-800页

作者： A.A.M.arafa S.Z.Rida h.Mohamed Department of Mathematics Faculty of ScienceSouth Valley University

In this paper,the homotopy analysis method (hAM) is applied to solve generalized biological *** fractional derivatives are described by Caputo's *** method introduces a significant improvementin this field over existing *** obtained using the scheme presented here agree well with the analyticalsolutions and the numerical results presented in Ref.[6].however,the fundamental solutions of these equations stillexhibit useful scaling properties that make them attractive for applications.

关键词： biological populations model fractional calculus homotopy analysis method Mittag-Leffier function

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Community Detection Applications in Mobile Networks:Towards Data-Driven Design for Next Generation Cellular Networks

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Journal of Communications and Information Networks 2023年第2期8卷 155-163页

作者： Ayman Gaber Nashwa Abdelbaki Tamer arafa School of Information Technology and Computer Science Nile UniversityGiza 12677Egypt

The existing radio access network(RAN)is facing many challenges to meet the very strict speed and latency requirements by different mobile applications in addition to the increasing pressure to reduce operating *** and development in RAN have been accelerated to tackle these challenges and to define how next generation mobile networks should look *** role of machine learning(ML)and artificial intelligence(AI)driven innovations within the RAN domain is strengthening and attracting lots of attention to tackle many of the challenging *** this paper we surveyed RAN network base stations(BSs)clustering and its applications in the *** paper also demonstrates how to leverage community detection algorithms to understand underlying community structures within *** areas(TAs)novel framework was developed by adapting existing community detection algorithm to solve the problem of statically partitioning a set of BSs into TA according to mobility ***,live network dataset in dense urban part of Cairo is used to assess how the developed framework is used to partition this part of the network more efficiently compared to other clustering *** obtained showed that the new methodology saved up to 34.6%of inter TA signaling overhead and surpassing other conventional clustering algorithms.

关键词： RAN mobility optimization RAN intelligence community detection ML

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Convenient One Pot Synthesis and Antibacterial Evaluation of Some New Mannich Bases Carrying 1,2,4-Triazolyl Moiety

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Chinese Journal of Chemistry 2011年第8期29卷 1661-1668页

作者： arafa, Wael A. A Mohamed, Asmaa S Department of Chemistry Faculty of Science Fayoum University Fayoum Egypt Department of Medical Chemistry Theodor Bilharz Research Institute Egypt

A series of Mannich bases were synthesized by a three-component Mannich reaction. The newly synthesized compounds were well characterized by elemental analyses, IR, NMR and mass spectroscopic studies. The potential antibacterial effects of the synthesized compounds were investigated using standard bacterial strains： Gram-positive and Gram-negative bacteria. Interestingly, all the synthesized compounds were observed to be promising leads, possessing moderate to significant inhibitory activity as compared to standard.

关键词： bi- 1,2,4-triazoles Schiff bases Mannich bases regioselectivity antibacterial activity

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