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Journal of Rare Earths 2014年第1期32卷 37-42页

作者： m.m.S.Sanad m.m.Rashad E.A.abdel-Aal m.F.El-Shahat K.Powers Central metallurgical R & D Institute Particle Engineering Research Center University of Florida Faculty of Science Ain Shams University

Dielectric ceramics of m（x）Al6（1-x）Si2O13 doped mullite were synthesized via co-precipitation technique. The X-ray diffrac-tion profiles revealed that these nanoparticles were crystallized well and the volume of mullite unit cell was increased as a function of the ionic radius of dopant ion. TEm images showed regular orthorhombic crystal morphology for the pure mullite sample. meanwhile, the doped samples exhibited slightly distorted crystal morphology of larger particle sizes. DSC thermograms evinced that the exo-thermic peak temperature of mullite was shifted to the lower value with m3＋ion insertion. The photoluminescence spectra were stud-ied for mullite samples, and it was found that the intensity of the emission spectra was affected by the m3＋ion type. It was found that, Y3＋doped mullite achieved the minimum dielectric loss value of 0.01 in the radio wave frequency region （1 mHz）. meanwhile, Gd3＋doped mullite achieved the minimum dielectric loss value of 0.09 in the microwave frequency region （1 GHz）.

关键词： rare earths doped mullite photoluminescence crystallization temperature dielectric ceramics

Construction of Optimal Quadrature Formulas Exact for Exponentional-trigonometric Functions by Sobolev's method

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Acta mathematica Sinica,English Series 2021年第7期37卷 1066-1088页

作者： aziz BOLTAEV Abdullo HAYOTOV Kholmat SHADImETOV V.I.Romanovskiy Institute of mathematics Uzbekistan Academy of Sciences46University Str.Tashkent 100174Uzbekistan V.I.Romanovskiy Institute of mathematics Uzbekistan Academy of Sciences4bUniversity Str.Tashkent 100174Uzbekistan Tashkent Railway Engineering Institute 1Odilxojaev Str.Tashkent 100167Uzbekistan

The paper studies Sard's problem on construction of optimal quadrature formulas in the space W_(2)^((m,0))by Sobolev's *** problem consists of two parts:first calculating the norm of the error functional and then finding the minimum of this norm by coefficients of quadrature *** the norm of the error functional is calculated with the help of the extremal *** using the method of Lagrange multipliers the system of linear equations for coefficients of the optimal quadrature formulas in the space W_(2)^((m,0)) is obtained,moreover the existence and uniqueness of the solution of this system are ***,the discrete analogue D_(m)(hβ)of the differential operatord^(2m)/dx^(2m)-1 is ***,Sobolev's method of construction of optimal quadrature formulas in the space W_(2)^((m,0)),which based on the discrete analogue D_(m)(hβ),is ***,for m=1 and m=3 the optimal quadrature formulas which are exact to exponential-trigonometric functions are ***,at the end of the paper the rate of convergence of the optimal quadrature formulas in the space W_(2)^((3,0))for the cases m=1 and m=3 are presented.

关键词： The extremal function the error functional discrete analogue Sobolev's method optimal coefficients

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Journal of Ocean Engineering and Science 2022年第4期7卷 321-326页

作者： H.I.abdel-Gawad m.Tantawy m.S.mani Rajan Department of mathematics Faculty of ScienceCairo UniversityGizaEgypt Department of Basic Sciences Faculty of EngineeringOctober 6 UniversityGizaEgypt Department of Physics University College of EngineeringAnna UniversityRamanathapuramIndia

The oscillatory motion on the ocean surface is a combination of a variety of different types of *** regularized waves are among ***,it is shown that they arise as solutions of the(1+2)-dimensional Benjamin-Bona-mahony equation(BBmE).Numerous works on(1+1)-dimensional BBmE were carried in the *** this paper,we consider the(1+2)-dimensional non-autonomous BBmE,with time-dependent *** model equation is completely *** objective is to find the exact solutions and investigate the relevant *** solve this issue,the extended unified method is used to find the exact solutions in the form of semi-self similar and self similar *** solve this issue,simi-larity transformations are ***,the generalized unified methods(GUm)are also used in the symbolic *** numerical results of these solutions are evaluated and are shown *** wave patterns of regularized waves in shallow water,near ocean shores,are ***-tory waves and vector of lumps with troughs are *** time-dependent coefficients are used,here,to control the different wave patterns that take the forms of the multi-U shaped wave with basins with a *** pattern formation occurs,which is in the form of two layers of lumps with *** tunneling is also *** waves patterns are *** stability of the steady state solutions is *** is found that the stability depends significantly on the dispersion coefficient.

关键词： (1+2)-dimensional Benjamin-Bona-mahony equation Extended unified method Wave patterns Similariton solutions

modern comprehensive study of the W Uma system TY Boo

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Research in Astronomy and Astrophysics 2015年第4期15卷 501-516页

作者： magdy m.Elkhateeb mohamed Ibrahim Nouh abdel-Naby S.Saad Astronomy Department National Research Institute of Astronomy and Geophysics Physics Department College of ScienceNorthern Border University mathematics Department Preparatory YearQassim University

New three color light curves of TY Boo were acquired during five nights from February to may 2006 in the BVR bandpass using a 50-cm F/8.4 Ritchey- Chr6tien telescope （Ba50） at the Baja Astronomical Observatory （Hungary）, with a 512×512 Apogee AP-7 CCD camera. A photometric solution of these light curves was obtained by means of the Wilson-Devinney code. The results showed that the less massive component is hotter than the more massive one, and the temperature difference between the components is △T -249 K. Long term investigation of the system based on all available data shows two stages of increase and a similar trend for decrease, which appears to be periodic behavior. A set of new light elements yields a new period （P = 0.3171506d） and shows a periodic decrease with the rate dP/dE -- 5.858×10^-12 d cycle-1, 6.742×10^-9 d yr-1 or 0.058 s century-1. The evolutionary status of the system is discussed.

关键词： binaries: eclipsing -- stars: evolution

Utilization of Small Size Bolti (<i>Talibia nilotica</i>) and Sardine (<i>Sardina pilchardus</i>) Fish in Preparing Canned Weaning Food Purees

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Food and Nutrition Sciences 2021年第7期12卷 719-731页

作者： Faten Farouk abdel-Salam Nadia A. Abd-El-aziz Saadia m. Hashem Food Science and Technology Department Faculty of Agriculture Alexandria University Alexandria Egypt meat and Fish Technology Research Department Food Technology Research Institute Agriculture Research Center Alexandria Egypt

Utilize small size of bolti and sardine fish in preparing fish based weaning foods rich in protein, essential amino acids, fat high in omega 3 fatty acids, minerals and vitamins was investigated. The proximate composition, nutritional value, physical and sensorial properties were evaluated, The results of the chemical composition showed that the moisture content of fish based weaning food purees ranged from 67.73% to 72.05%. On dry weight basis, the five prepared formulations considered rich in protein (37.39% - 44.86%), fat (26.55% - 30.43%), ash (6.53% - 12.23%) and low in carbohydrates (20.70% - 22.18%). Using fish bones with muscles in preparing weaning food puree caused a marked rise in its content of Ca, P, Fe, and Zn levels especially in purees formulated from bolti. Weaning food purees containing sardine fish rich, in fat, were higher in vitamin A and D than those formulated from bolti one. Palmitic acid (C16:0), stearic acid (C18:0), and myristic acid (C14:0) represented the major saturated fatty acids in the prepared formulations. Weaning food purees containing sardine fish had relatively higher levels of sulfur-mily:Verdana;">containing amino acids and slight lower values of lysine, alanine and glycine than these including bolti fish. The In vitro protein digestibility index (IVPDI) of the

关键词： Weaning Foods Protein Digestibility IVPDI Fish Based Food Products Children Nutrition

Seed Priming and Foliar Supplementation withβ-aminobutyric Acid Alleviates Drought Stress through mitigation of Oxidative Stress and Enhancement of Antioxidant Defense in Linseed(Linum usitatissimum L.)

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Phyton-International Journal of Experimental Botany 2023年第11期92卷 3113-3131页

作者： Tauqeer Ahmad Yasir muhammad Ateeq Allah Wasaya mubshar Hussain Naeem Sarwar Khuram mubeen mudassir aziz muhammad Aamir Iqbal Chukwuma COgbaga Ibrahim Al-Ashkar md Atikur Rahman ayman El Sabagh Department of Agronomy University of LayyahLayyah31200Pakistan Department of Agronomy Bahauddin Zakariya UniversityMultan60000Pakistan State Key Lab of Crop Stress Biology for Arid Areas College of AgronomyNorthwest A&F UniversityYangling712100China Department of Agronomy MNS University of AgricultureMultan60000Pakistan Department of Agronomy Faculty of AgricultureUniversity of Poonch RawalakotRawalakot10250Pakistan Independent Researcher MiddlesbroughNorth YorkshireUK Plant Production Department College of Food and Agriculture SciencesKing Saud UniversityP.O.Box 2460Riyadh11451Saudi Arabia Grassland and Forage Division National Institute of Animal ScienceRural Development AdministrationCheonan31000Korea Department of Field Crops Faculty of AgricultureSiirt UniversitySiirt56100Turkey Department of Agronomy Faculty of AgricultureKafrelsheikh UniversityKafr El-Shaikh33516Egypt

Drought is one of the critical limitations to agricultural soils and crop *** of water is increasing due to climate change that lead to increasing threats to global food ***,ecofriendly and cost effective strategies are highly desirable for mitigating drought stress along with sustainable and smart agricultural *** aim of the study was to mitigate DS using seed priming and exogenous supplementation ofβ-aminobutyric acid(BABA)in linseed(Linum usitatissimum L.).Different doses(0,50,100 and 150μm)of BABA were used for seed priming agent and foliar spraying under three soil moisture levels viz.,25%(Sm25),45%(Sm45)and 65%(Sm65).The response variables of both experiments included different agro-botanical traits and oxidative stress indicators such as melondialdehyde content,free proline accumulation,and antioxidant defense in *** linseed plants showed water stress at Sm25 that reduced plant height,number of branches per plant,time taken to flower initiation and heading,and root and shoot dry ***,the number of capsules and seeds per capsule showed a significant decline at Sm25,which led to a drastic reduction in 100-seed weight yield in linseed plants in both ***,seed priming and foliar supplementation with of BABA(50–100μm)significantly improved these morpho-agronomical attributes in linseed plants under *** results revealed that the BABA was fully active in linseed plants at ***,the combination of Sm25 with BABA significantly improved the antioxidant enzymes superoxide dismutase(SOD),catalase(CAT),ascorbate peroxidase(APX),and peroxidase(POD)activity,which significantly enhanced DS tolerance in linseed *** findings might be useful to oil seed breeders and farmers linseed for breeding program in linseed plants as well as sustainable agricultural production of oil seed crop plants.

关键词： Linseed water stress signaling molecule climate change biostimulant ecofriendly approach sustainable agricultural

microstructural evolution,dislocation density and tensile properties of Al–6.5Si–2.1Cu–0.35mg alloy produced by different casting processes

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Journal of materials Science & Technology 2021年第36期95卷 145-157页

作者： S.Samat m.Z.Omar A.H.Baghdadi I.F.mohamed A.Rajabi A.m.aziz Department of mechanical and manufacturing Engineering Faculty of Engineering and Built EnvironmentUniversiti Kebangsaan MalaysiaBangiUKM 43600Malaysia

Al–Si–Cu–mg foundry alloys are used in casting process ***,their strength properties remain low due to their microstructural characteristics and *** this work,the microstructural characteristics,dislocation densities,and mechanical properties of Al–Si–Cu–mg cast alloys prepared through different casting methods were studied *** casting processes,namely,gravity casting(GC),rheocasting(RC),thixoforming(Thixo),and Thixo with heat treatment,were *** GC and RC samples had mainly dendriticα-Al phase microstructures and exhibited coarse Si particles and intermetallic compounds in their interdendritic *** contrast,the Thixo and heat-treated Thixo(HT-Thixo)samples exhibited microstructural refinement with uniformly distributedα-Al globules,fine fibrous Si particles,and fragmented intermetallic compounds amongα-Al *** accumulation of dislocation densities increased in the Thixo sample as the strain was increased due to plastic ***,the ultimate tensile strength and yield strength of the HT-Thixo sample increased by 87%and 63%,respectively,relative to those of the GC *** cleavage fracture displayed by the GC and RC samples led to brittle ***,the Thixo and HT-Thixo samples presented dimple-based ductile fracture.

关键词： Al–Si–Cu–mg alloy Thixoforming microstructure mechanical property Dislocation density

Neutron activation analysis of ceramic tiles and its component and radon exhalation rate

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Journal of Environmental Sciences 2004年第1期16卷 94-99页

作者： A.El-Shershaby A.Sroor F.Ahmed A.S.abdel-Haleem Z.abdel Nuclear Physics Laboratory Faculty of WomenAin-Shams UniversityNuclear Physics LaboratoryFaculty of WomenAin-Shams UniversityIonizing Radiation DepartmentNational Institute for StandardsHot Laboratories CenterAtomic Energy AuthorityNuclear Physics LaboratoryFaculty of WomenAin-Shams University Cairo EgyptCairo EgyptGiza EgyptCairo EgyptCairo Egypt

The concentrations of 20 trace elements in several ceramics tiles and ceramic composites used in Egypt were elementally analyzed by neutron activation analysis(NAA) technique. The samples and standard were irradiated with reactor for 4 h(in the Second Research Egyptian Reactor(Et-RR-2)) with thermal neutron flux 5.9×10 13 n/(cm 2·s).The gamma-ray spectra obtained were measured for several times by means of the hyper pure germanium detection system(HPGe). Also a solid state nuclear track detector(SSNTD) CR-39, was used to measure the emanation rate of radon for these samples. The radium concentrations were found to vary from 0.39—3.59 ppm and the emanation rates were found to vary from (0.728—5.688) × 10 -4 kg/(m 2· s).The elemental analysis of the ceramic tiles and ceramic composites have a great importance in assigning the physical properties and in turn the quality of the material.

关键词： ceramic neutron activation analysis(NAA) radon emanation solid state nuclear track detector(SSNTD)

Change Detection of Lake Chad Water Surface Area Using Remote Sensing and Satellite Imagery

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Journal of Geographic Information System 2021年第5期13卷 561-577页

作者： abdel-aziz Adam mahamat Adeeba Al-Hurban Nehaya Saied Integrated International for Environmental Services (IIES) Kuwait City Kuwait Earth and Environmental Sciences Department Faculty of Science Kuwait University Kuwait City Kuwait

The Lake Chad located in the west-central Africa in the Sahel region at the edge of the Sahara experienced severe drought during 1970s and 1980s and overexploitation (unintegrated and unsustainable use), which is a result of variant land uses and water management practices during the last 50 years. This resulted in a decline of the water level in the Lake and surrounding rivers. The present study analyzed satellite images of Lake Chad from Landsat-mSS, Landsat-OLI to investigate the change of the open water surface area during the years of 1973, 1987, 2001, 2013, and 2017. Supervised classifications were performed for the land cover analysis. The open water area in 1973 was covering 16,157.34 km2 approximately, and that was 64.6% of the total lake area in the 1960s. As an ultimate result of the extreme drought that the study area witnessed through 1970s-1980s, the open water area has decreased to 1831.44 km2, i.e. around 11.33%, compared to that in 1973. The dilemma that the study area is suffering from is believed to be a catastrophic complication of the aforementioned drought crisis, which arose as an ultimate result the climate change, global warming, and the unintegrated and unsustainable use of water challenges the study area is still encountering.

关键词： Satellite Imagery Landsat Remote Sensing GIS Drought Overexploitation

Free vibration of layered cylindrical shells filled with fluid

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Applied mathematics and mechanics(English Edition) 2016年第6期37卷 803-820页

作者： m.D.NURUL IZYAN K.K.VISWANATHAN Z.A.aziz K.PRABAKAR UTm Centre for Industrial and Applied mathematics Ibnu Sina Institute for Scientific & Industrial ResearchUniversiti Teknologi Malaysia Department of mathematical Sciences Faculty of ScienceUniversiti Teknologi Malaysia Department of Electrical and Computer Engineering Pusan National University

The vibration of the layered cylindrical shells filled with a quiescent, incompressible, and inviscid fluid is analyzed. The governing equations of the cylindrical shells are derived by Love＇s approximation. The solutions of the displacement functions are assumed in a separable form to obtain a system of coupled differential equations in terms of the displacement functions. The displacement functions are approximated by Bickley-type splines. A generalized eigenvalue problem is obtained and solved numerically for the frequency parameter and an associated eigenvector of the spline coefficients. Two layered shells with three different types of materials under clamped-clamped （C-C） and simply supported （S-S） boundary conditions are considered. The variations of the frequency parameter with respect to the relative layer thickness, the length-to-radius ratio, the length-to-thickness ratio, and the circumferential node number are analyzed.

关键词： Love's shell theory cylindrical shell spline method