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Permutation-substitution image encryption scheme based on a modified chaotic map in transform domain

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Journal of Central South University 2017年第9期24卷 2049-2057页

作者： ramadan Noha Ahmed hossameldin h el-khamy Said E abd el-Samie fathi E faculty of electronic Engineering Menofia University faculty of Engineering Alexandria University

A new chaotic image encryption scheme based on permutation and substitution in the Fourier domain is *** Fourier Transform(FRFT)is used before the encryption scheme to get a large degree of *** permutation is achieved by Baker map and the substitution by a key-related-to-plain-image algorithm based on the modified Logistic *** of the Logistic map is developed to increase the space of the encryption key,and hence increase the *** key of the encryption algorithm dependents on the plain image,and thus,the cipher image is sensitive to both the initial key and the plain image to resist known-plaintext and chosen plaintext *** key space is large and hence the algorithm can effectively resist brute-force *** proposed scheme is examined using different performance evaluation metrics and the results prove that the proposed scheme is highly secure,and it can effectively resist different attacks.

关键词： Backer map chaotic encryption fractional Fourier transform (FRFT) modified Logistic map

Cylindrical Three-Dimensional Dust-Ion Acoustic Propagation in Plasmas

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Communications in Theoretical Physics 2018年第9期69卷 325-330页

作者： S.K.el-Labany E.K.el-Shewy h.N.abd el-razek A.A.el-rahman Theoretical Physics Group Faculty of Science Domietta University Department of Physics Taibah University Theoretical Physics Group Faculty of Science Mansoura University Department of Physics Faculty of Science Assiut University

wave properties of solitons in an unmagnetized four-component dusty plasma system contains isothermal distributed electrons, mobile ions, and negative-positive dusty grains have been examined. To study DIA wave properties,a reductive perturbation (RP) analysis is used. By a reductive perturbation (RP) analysis under convenient coordinate transformation, the three dimension Kadomtsev-Petviashvili equation in cylindrical coordinates is obtained. The effects of dust grain charge on soliton pulse structures are studied. More specifically, solitary profile depending on the axial,radial, and polar angle coordinates with time is discussed. This investigation may be viable in plasmas of the Earth’s mesosphere.

关键词： dust plasmas 3D-CKP equation dusty-ion acoustic solitary waves isothermal electrons

Plant phosphatidylinositol-specific phospholipase C at the center of plant innate immunity

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Journal of Integrative Plant Biology 2017年第3期59卷 164-179页

作者： Ahmed M.abd-el-haliem Matthieu h.A.J.Joosten Laboratory of Phytopathology Wageningen University Droevendaalsesteeg 1 6708 PB Wageningen The Netherlands Plant Physiology Swammerdam Institute for Life Sciences University of Amsterdam Science Park 904 1098 XH Amsterdam The Netherlands

Understanding plant resistance to pathogenic microbes requires detailed information on the molecular mechanisms controlling the execution of plant innate immune responses. A growing body of evidence places phosphoinositide-specific phospholipase C （PI-PLC） en- zymes immediately downstream of activated immune receptors, well upstream of the initiation of early defense responses. An increase of the cytoplasmic levels of free Ca2＋, lowering of the intercellular ph and the oxidative burst are a few examples of such responses and these areregulated by PI-PLCs. Consequently, PI-PLC activation represents an early primary signaling switch between elicitation and response involving the controlled hydrolysis of essential signaling phospholipids, thereby simulta- neously generating lipid and non-lipid second messenger molecules required for a swift cellular defense response. here, we elaborate on the signals generated by PI-PLCs and their respective downstream effects, while providing an inventory of different types of evidence describing the involvement of PI-PLCs in various aspects of plant immunity. We project the discussed information into a model describing the cellular events occurring after the activation of plant immune receptors. With this review we aim to provide new insights supporting future research on plant PI-PLCs and the development of plants with improved resistance.

关键词： Pradeep Kachroo University of Kentucky USA

Physico-analytical Studies on Salicylaldehyde Thiosemicarbazone Complexes

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Journal of Materials Science & Technology 1998年第5期14卷 434-440页

作者： Abo el Fetoh, S.h. abd el-Kareem, A.T. wassel, M.A. Eid, A.E. faculty of Girls-Ain Shams University Egypt National Research Centre Egypt faculty of Science El-Menoufia University Egypt faculty of Science Al-Azhar University Egypt

The complexes of salicylaldehyde thiosemicarbazone with Pd, Cu and Ru were prepared. The prepared complexes were characterized by spectroscopic, element and thermal analyses and D.C. conductivity measurements. The antimicrobial activity of all the prepared compounds against gram-positive, gram-negative and fungi was studied. From these studies, it has been obtained that the ligand is bonded to the metals through O, N and S, but to palladium in [Pd (h//2L//2)] Cl//2 only through N and O. Biological studies confirm that the organic effect on both gram-positive and gram-negative bacteria is very weak and their complexes have no effect on fungi, but Cu-complex has strong influence on both types of bacteria. (Edited author abstract) 22 Refs.

关键词： Metallorganic polymers

electrical,thermal and electrochemical properties of γ-ray-reduced graphene oxide

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International Journal of Minerals,Metallurgy and Materials 2021年第10期28卷 1726-1734页

作者： M.M.Atta h.A.Ashry G.M.Nasr h.A.abd el-Rehim radiation Physics Department National Center for Radiation Research and Technology(NCRRT)Atomic Energy AuthorityCairo 11787Egypt Physics Department Faculty of ScienceCairo UniversityCairo 12613Egypt radiation Chemistry Department National Center for Radiation Research and Technology(NCRRT)Atomic Energy AuthorityCairo 11787Egypt

The properties of γ-ray-reduced graphene oxide samples(GRGOs)were compared with those of hydrazine hydrate-reduced graphene oxide(hRGO).Fourier transform infrared spectroscopy,X-ray diffractometry,raman spectroscopy,Brunauer-Emmett-Teller surface area analysis,thermogravimetric analysis,electrometry,and cyclic voltammetry were carried out to verify the reduction process,structural changes,and defects of the samples,as well as to measure their thermal,electrical,and electrochemical *** with γ-rays distorted the structure of GRGOs and generated massive defects through the extensive formation of new smaller sp^(2)-hybridized domains compared with those of *** thermal stability of GRGOs was higher than that of hRGO,indicating the highly efficient removal of thermally-labile oxygen species by γ-*** prepared at 80 kGy showed a pseudocapacitive behavior comparable with the electrical double-layer capacitance behavior of ***,the specific capacitance of GRGO was enhanced by nearly three times compared with that of *** results reflect the advantages of radiation reduction in energy storage applications.

关键词： graphene γ-ray electrical thermal electrochemical

Extraction of cerium(Ⅳ) using tributyl phosphate impregnated resin from nitric acid medium

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Transactions of Nonferrous Metals Society of China 2012年第1期22卷 206-214页

作者： O.S.helALY M.S.abd el-GhANY M.I.MOUSTAfa A.h.ABUZAID N.M.abd el-MONEM I.M.ISMAIL Nuclear Materials Authority P.O.Box 530 El-MaadiCairoEgypt faculty of Engineering Chem.Eng.Dept.Cairo UniversityGizaEgypt

Tributyl phosphate （TBP） solvent was used for impregnation into Amberlite XAD-16 nonionic polymeric resin beads using the wet method to prepare solvent impregnated resin （SIR）. Undiluted TBP in a ratio to the resin support （volume to mass） of 6.0 at room temperature （RT） in 24 h was impregnated the resin with a mass ratio of 1.944, while the prepared gross sample of SIR at the ratio of solvent to resin of 3.0 was impregnated with a mass ratio of 1.88. Cerium（Ⅳ） oxide concentrate, prepared from crude Egyptian monazite sand, containing 37% cerium, 1.6% thorium and about 40% the other trivalent rare earth oxides, was used to prepare cerium（Ⅳ） nitrate solution for extraction using the prepared SIR. The impregnated resin was satisfactory for Ce（Ⅳ） extraction from nitric acid medium at room temperature. Cerium loading capacity of the impregnated resin reached 95.6% of the calculated theoretical capacity （173 g/kg （Ce/SIR）） under the conditions of 51.57 g/L cerium and 2.48 g/L thorium, 5.0 mol/L free nitric acid, solution to resin ratio of 10.0 and contacting the phases for 5.0 min. The loading capacity reached 98.75% when cerium concentration was increased to 91.43 g/L under the same conditions.

关键词： cerium (Ⅳ) crude monazite sand tributyl phosphate impregnated resin extraction nitric acid medium

Detection of virulent strains of helicobacter pylori and its relation to symptoms and signs in children

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Asian Pacific Journal of Tropical Medicine 2010年第1期3卷 59-62页

作者： fayed S abd el Dayem S hussein h Sherief M el-Naghi S Pediatric Department Al Azhar University Pediatric Department National Research Centre Microbiology Department Al Azhar University Pediatric Department National Hepatology and Tropical Medicine Research

Objective:To detect the prevalence of helicobacter polori(***) in a group of pediatric patients complaining of gastrointestinal disorders,and to identify the virulent strains of h. pylori and its relation to peptic ***:The study included 60 patients(41 males and 19 females),aged from 6 months to 14 years,with complaining of different gastrointestinal *** IgG antibodies were *** examination of the oesophagus, stomach and duodenum was done in all patients using a fibreoptic *** addition, gastric antral biopsies were taken for diagnosis of *** infection in the following test: rapid urease test,histopathologic examination and *** cytotoxin assay of virulent strains was *** infection was diagnosed if 3 or more tests for diagnosis were found to be ***:33 out of 60 patients(55%) was positive.12(20%) patients had positive toxin producing strains(virulent strains).Virulent strain had a significantly closer relationship with recurrent abdominal pain,while no difference was found in other symptoms. Age of patients showed a highly significant positive correlation with virulent *** strain. histopathological finding revealed that oesophagitis was significandy common in patients with negative *** and histopathological findings revealed that virulent strain had a significandy higher gastritis and oesophagitis ***:Infection by virulent strains of *** in children is not uncommon:It is associated with endoscopic and histopathologic *** cases infected with virulent strain showed positive results by using rapid urease test,culture and IgG antibodies.

关键词： helicobacter pylori IgG antibody Pediatric Gastrointestinal disorder

Oxidation Resistance of the Aluminide Coating Formed on Carbon Steels

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Journal of Materials Science & Technology 1997年第5期13卷 383-388页

作者： Soliman h.M. Mohamed K.E. abd el-Azim M.E. hammad F.h. Metallurgy Dept. Atomic Energy Authority Cairo Egypt

Low and medium carbon steels were aluminized by the pack aluminizing technique using halideactivated pure-Al and Fe-Al packs. The effect of mixture composition, aluminizing temperatureand time and C content of the steel substrate on the structure and thickness of the aluminidelayer, and on the oxidation resistance was investigated. The optimum oxidation resistance canbe achieved with a low carbon steel substrate when the intermetallic phases Fe3Al and FeAlform the surface of the aluminide layer. In this case, the Al concentration at the surface of thealuminide coating is at least ≥15 wt pct. Formation of high Al concentration phases (FeAl3 andFe2Al5) during aluminizing should be avoided as they tend to embrittle the aluminide layer andreduce its oxidation resistance.

关键词： OO Figure Oxidation Resistance of the Aluminide Coating Formed on Carbon Steels

Improvement of geotechnical properties of sabkha soil utilizing cement kiln dust

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第4期9卷 749-760页

作者： abdullah A.Al-homidy Mohammed h.Dahim Ahmed K.abd el Aal Department of Civil Engineering Najran University Geology Department Faculty of ScienceAl Azhar University

Improvement of properties of weak soils in terms of strength,durability and cost is the key from engineering point of *** weak soils could be stabilized using mechanical and/or chemical *** added during chemical stabilization could improve the engineering properties of treated *** utilized have to satisfy noticeable performance,durability,low price,and can be easily *** cement kiln dust(CKD) is industrial by-product,it would be a noble task if this waste material could be utilized for stabilization of sabkha *** study investigates the feasibility of utilizing CKD for improving the properties of sabkha *** samples are prepared with 2% cement and 10%,20% or 30% CKD and are tested to determine their unconfined compressive strength(UCS),soaked California bearing ratio(CBR) and *** of stabilization is studied utilizing advanced techniques,such as the scanning electron microscope(SEM),energy dispersive X-ray analysis(EDX),backscattered electron image(BEI) and X-ray diffraction analysis(XRD).It is noted that the sabkha soil mixed with 2% cement and 30% CKD could be used as a sub-base material in rigid *** incorporation of CKD leads to technical and economic benefits.

关键词： Sabkha soil Geotechnical properties Soil improvement Cement kiln dust(CKD) Unconfined compressive strength(UCS) Soaked California bearing ratio(CBR) Durability