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Dielectric Behavior of modified Cellulose

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Journal of materials Science & Technology 1999年第2期15卷 164-168页

作者： el-Henawii, S.A. Saad, S.m. el-anwar, i.m. Faculty of Science Helwan University Egypt Chemistry Department Faculty of Science Al-Azhar University Egypt Physical Chemistry Unit of the N.R.C Egypt

The dielectric constants and the dielectric loss, as well as the activation energy of dielectric relaxation of silylated cellulose were measured within the frequency range 10**5 to 10**7 Hz and the temperature range from 10 to 50 degree C. The test samples were activated cellulose with ethylene di.m.ne, with sodi.m.hydroxide and inactivated cellulose before and after silylation. The measurements were carried out using a multi-deka-meter. Cellulose molecules are more activated by treatment with ethylene di.m.ne than with sodi.m.hydroxide. Generally, silylation causes a marked decrease of the dielectric constant and dielectric loss, meanwhile the silylated samples are affected with the pretreatment of linters with sodi.m.hydroxide and ethylene di.m.ne. (Edited author abstract) 28 Refs.

关键词： Cellulose

Arctic sea-ice extent: No record minimum in 2023 or recent years

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 52-55页

作者： Ola m.Johannessen Tor i.Olaussen Nansen Scientific Society BergenNorway Nansen Environmental and Remote Sensing Center BergenNorway

Arctic sea-ice extent reaches its minimum each year in September. On 11 September 2023 the minimum was 4.969 million square kilometers(***^(2)). This was not a record low, which occurred in 2012, when the minimum was 4.175 ***^(2), 0.794 ***^(2) less than the minimum in 2023. However, the ice extent had decreased by 0.432 ***^(2) compared with 2022. Nevertheless, the summer melting in 2023 was remarkably less than expected when considering the strong heat waves in the atmosphere and ocean, with record temperatures set around the world. in general, there is a high correlation between the long-term decrease in sea-ice extent and the increasing CO_(2) in the atmosphere, where the increase of CO_(2) in recent decades explains about 80% of the decrease in sea ice in September, while the remainder is caused by natural variability.

关键词： Sea ice Arctic minimum ice Climate

Assessment of lnc RNA GAS5, lnc RNA HEiH, lnc RNA BiSPR and its m RNA BST2 as serum innovative non-invasive bi.m.rkers: Recent insights into Egyptian patients with hepatitis C virus type 4

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World Journal of Gastroenterology 2020年第2期26卷 168-183页

作者： Nourhan m el Samaloty marwa i Shabayek Ramy S Ghait Shohda A el-maraghy Sherine m Rizk maha m el-Sawalhi Biochemistry Section PharmacologyToxicology and Biochemistry DepartmentFaculty of Pharmaceutical Sciences and Pharmaceutical IndustriesFuture UniversityCairo 11795Egypt internal medicine Gastroenterology and Hepatology DepartmentFaculty of MedicineAin Shams UniversityCairo 11566Egypt Biochemistry Department Faculty of PharmacyCairo UniversityCairo 11562Egypt

BACKGROUND Hepatitis C virus(HCV)infection and its consequent complications are undeniably a public health burden worldwide,particularly in *** evidence suggests that many lncRNAs have relevant roles in viral infections and antiviral *** To investigate the expression profiles of circulating lncRNAGAS5,lncRNAHEiH,lncRNABiSPR and mRNABST2 in naïve,treated and relapsed HCV Egyptian patients,to elucidate relation to HCV infection and their efficacy as innovative bi.m.rkers for the diagnosis and prognosis of HCV *** One hundred and thirty HCV-infected Egyptian patients and 20 healthy controls were included in this *** lncRNAs and mRNABST2 were measured using quantitative real-time polymerase chain reaction(qRT-PCR).RESULTS Our results indicated that serum lncRNAGAS5 and LncRNABiSPR were upregulated,whereas mRNA BST2 and LncRNA HEiH were downregulated in naïve *** contrast,HCV patients treated with sofosbuvir and simeprevir;with sofosbuvir and daclatasvir;or with sofosbuvir,daclatasvir and ribavirin exhibited lower levels of lncRNAGAS5 and lncRNABiSPR with higher mRNABST2 compared to naïve ***,patients relapsed from sofosbuvir and simeprevir showed higher levels of these lncRNAs with lower mRNABST2 compared to treated ***5 and lncRNABiSPR were positively correlated with viral load and ALT at PmRNABST2 was negatively correlated with viral load at Pignificant positive correlation between lncRNA HEiH and AFP was observed at Pifferential expression of these RNAs suggests their involvement in HCV pathogenesis or antiviral response and highlights their promising roles in diagnosis and prognosis of HCV.

关键词： lncRNA GAS5 lncRNA BiSPR mRNA BST2 lncRNA HEiH Hepatitis C Bi.m.rkers

Petrology, geochemistry, radioactivity, and m–W type rare earth element tetrads of el Sela altered granites, south eastern desert,Egypt

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Acta Geochimica 2019年第1期38卷 95-119页

作者： A.m.el mezayen m.A.Heikal m.G.el-Feky H.A.Shahin i.K.Abu Zeid S.R.Lasheen Geology Department Faculty of Science Al Azhar University Nuclear material Authority

The southern part of the Eastern Desert of Egypt—about 30 km southwest of Abu-Ramad city—is mainly covered by ophiolitic rocks(Sul Hamed), island arc assemblage, younger granites(muscovite granites of Qash Amer and two mica granites of el Sela), and various acidic and basic dikes. Field, petrological, and geochemical studies indicate that the el Sela shear zone has been subject to hydrothermal and supergene alteration such as kaolinization, albitization, sericitization, and hematitization. it is invaded by quartz ENE–WSW veins associated with hydrothermal alteration accompanied by radioactive mineralization. The investigated younger granitic rocks had very low contents of compatible elements, such as Cr, Ni,and Co; and high contents of incompatible elements, such as Zr, and large ion lithophiles, such as Sr, especially in the el Sela shear zone. major oxide and trace element analyses revealed calc-alkaline affinity and peraluminous *** highly differentiated granitic rocks' lower Zr/Hf and higher Y/Ho than the normal ratio are consistent with hydrothermal alteration. most samples had rare earth element(REE)-patterns with an m-type tetrad effect in the first and fourth segments and a W-type tetrad in the third segment. The average ∑REE in the studied granites was lower than the world granite average; the ratio of light to heavy REEs greater. The main radioactive, urani.m.bearing, and uraniferous Fe and mn minerals are uranothorite,autunite, uranophane and autunite as compounds, kasolite,columbite, xenotime, uranophane-bearing zircon and jarosite, silver-bearing pyrite, hematite, and autunite-bearing pyrolusite.

关键词： Geochemistry REE-tetrad effect Radioactive minerals Radi.m.tric measurements Qash Amer el Sela

Peculiarity of magnetoresistance of discontinuous ferromagnetic thin fi.m.

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international Journal of minerals,metallurgy and materials 2017年第12期24卷 1459-1463页

作者： Yu.O. Shkurdoda i.m. Pazukha A.m. Chornous Department of Applied Physics Sumy State UniversitySumy 40007Ukraine

The magnetoresistive properties of discontinuous ferromagnetic Fe and Co thin fi.m. deposited by electron-beam sputtering onto glass substrates at room temperature were investigated. Tunnel magnetoresistance(mR) was observed for all of the as-deposited samples. The maximum mR was observed for Fe thin fi.m. with an effective thickness of 17 nm. in the case of the Co thin fi.m., the annealing process led to a change of the type of mR to anisotropic at Co fi.m.thicknesses(dCo) of 15 ≤ d_(Co) ≤ 25 nm and to positive isotropic at thicknesses of d_(Co) m. By contrast, the mR type of Fe thin fi.m. did not change.

关键词： discontinuous thin fi.m. ferromagnetic structure magnetoresistance peculiarity

2D CFD Analysis and Experimental Analysis on the Effect of Hub to Tip Ratios on the Performance of 0.6 m impulse Turbine

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Journal of Thermal Science 2004年第4期13卷 315-320页

作者： A. THAKKER m.el. HEmRY Wave Energy Research Team Department of mechanical and Aeronautical Engineering University of Limerick IrelandWave Energy Research Team Department of Mechanical and Aeronautical Engineering University of Limerick Ireland

The objective of this paper is to present the performance comparison of 2D Computational Fluid Dynamics (CFD) analysis with experimental analysis of 0.6 m impulse turbine with fixed guide vanes for both 0.6 and 0.7 hub to tip ratio (H/T). Also the comparison of 2D CFD analysis of the said turbine with different values of H/T ranging from 0.5 to 0.7. A 2D-cascade model was used for CFD analysis while uni-directional steady flow was used for experimental analysis. The blade and guide vane geometries are based on 0.6 m rotor di.m.ter, with optimum profile, and different H/T of 0.5, 0.6 and 0.7. it was concluded from 2D CFD analysis that 0.5 H/T ratio performances was higher than that of 0.6 and 0.7 H/T at peak efficiency and the operational flow range for 0.5 H/T was found to be wider than that of 0.6 and 0.7 H/T ratio.

关键词： wave energy impulse turbine computational fluid dynamics (CFD).

Use of breakthrough experiment to evaluate the performance of hydrogen isotope separation for metal-organic frameworks m-mOF-74(m=Co, Ni, mg, Zn)

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Science China Chemistry 2020年第7期63卷 881-889页

作者： Yanan Si Wenjing Wang el-Sayed m.el-Sayed Daqiang Yuan State Key Laboratoty of Structural Chemistry Fujian Institute o f Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of the Chinese Academy of Sciences Beijing 100049China Chemical Refining Laboratory Refining DepartmentEgyptian Petroleum Research InstituteNasr CityCairoEgypt

The unique adsorption performance of metal-organic frameworks(mOFs) indicates a new direction for gas separation and purification. The low-temperature distillation, as a traditional technique for hydrogen isotope separation, is limited as it is a high energy-and cost-intensive process. instead of utilizing such a conventional separation route, we use ordered microporous frameworks based on a physical adsorption mechani.m.to solve the challenge of hydrogen isotope separation. Herein we analyze m-mOF-74(m=Co, Ni, mg, Zn), featuring a hexagonal channel about 11 ? and high density of open metal sites, for their ability to separate and purify deuteri.m.from the hydrogen isotope mixture by dynamic column breakthrough experiments. Our results show that the combination of the strength of binding sites, density of coordinatively unsaturated metal sites and hydrogen isotope adsorption capacity of materials renders Co-mOF-74 as an optimal adsorbent for the capture of deuteri.m.from hydrogen isotope mixtures in a simulated industrial process.

关键词： hydrogen isotope separation breakthrough experiment mOF-74

Analysis of strong refractive effect within 11Li projectile structure

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Chinese Physics C 2021年第2期45卷 414-425页

作者： Kassem O.Behairy m.el-Azab Farid Awad A.ibraheem Ola Ramadan m.anwar Physics Department Aswan UniversityAswan 81528Egypt Physics Department Assiut UniversityAssiut 71516Egypt Physics Department King Khalid UniversityAbhaSaudi Arabia Physics Department Al-Azhar UniversityAssiut 71524Egypt

in the context of the double folding optical model,the strong refractive effect for elastic scattering of 11Li+12C and 11Li+28Si systems at incident energies of 29,50,and 60 meV/n is *** folded potentials are generated based on a variety of nucleon-nucleon interactions with the suggested density distributions for the halo structure of 11Li *** rearrangement term(RT)of the extended realistic density dependent CDm3Y6 effective interaction is *** imaginary potential was taken in the traditional standard Woods-Saxon *** results for the calculated potentials are obtained,with a slight effect of the RT in CDm3Y6 *** reproduction with a normalization factor close to one for the observed angular distributions of the elastic scattering differential cross section has been achieved using the derived *** obtained reaction cross-section is studied as a guide by extrapolating our calculations and previous results.

关键词： optical model elastic and inelastic scattering halo nuclei folding model refraction effect

Advanced Functional electromagnetic Shielding materials:A Review Based on micro‑Nano Structure interface Control of Bi.m.ss Cell Walls

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Nano-micro Letters 2025年第1期17卷 98-134页

作者： Yang Shi.m.ngjun Wu Shengbo Ge Jianzhang Li Anoud Saud Alshammari Jing Luo mohammed A.Amin Hua Qiu Jinxuan Jiang Yazeed m.Asiri Runzhou Huang Hua Hou Zeinhom m.el‑Bahy Zhanhu Guo Chong Jia Kaimeng Xu Xiangmeng Chen Co‑innovation Center of Efficient Processing and Utilization of Forest Resources College of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037People’s Republic of China State Key Laboratory of Efficient Production of Forest Resourced Beijing Forestry UniversityQinghua East Road 35Haidian DistrictBeijing 100083People’s Republic of China Department of Physics Faculty of Sciences‑ArarNorthern Border UniversityArar 91431Saudi Arabia Department of Chemistry College of ScienceTaif UniversityP.O.Box 1109921944 TaifSaudi Arabia Shaanxi Key Laboratory of macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China integrated Composites Lab Department of Mechanical and Construction EngineeringNorthumbria UniversityNewcastle Upon Tyne NE18STUK College of materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024People’s Republic of China Department of Chemistry Faculty of ScienceAl-Azhar UniversityNasr CityCairo 11884Egypt Yunnan Provincial Key Laboratory of Wood Adhesives and Glued Products International Joint Research Center for Biomass MaterialsSouthwest Forestry UniversityKunming 650224People’s Republic of China School of Science Henan Agricultural UniversityZhengzhou 450002People’s Republic of China

Research efforts on electromagnetic interference(Emi)shielding materials have begun to converge on green and sustainable bi.m.ss *** materials offer numerous advantages such as being lightweight,porous,and *** to their porous nature,interfacial compatibility,and electrical conductivity,bi.m.ss materials hold significant potential as Emi shielding *** concerted efforts on the Emi shielding of bi.m.ss materials have been reported,this research area is still relatively new compared to traditional Emi shielding *** particular,a more comprehensive study and summary of the factors influencing bi.m.ss Emi shielding materials including the pore structure adjustment,preparation process,and micro-control would be *** preparation methods and characteristics of wood,bamboo,cellulose and lignin in Emi shielding field are critically discussed in this paper,and similar bi.m.ss Emi.m.terials are summarized and *** composite methods and fillers of various bi.m.ss materials were *** paper also highlights the mechani.m.of Emi shielding as well as existing prospects and challenges for development trends in this field.

关键词： Bi.m.ss materials electromagnetic interference shielding micro-nano structure interface control Conductivity