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Two spectrophotometric methods for simultaneous determination of some antihyperlipidemic drugs

Journal of Pharmaceutical Analysis 2012年第4期2卷 279-284页

作者： Nada S.Abdelwahab Badr A.El-Zeiny Salwa I.Tohamy beni-suif university Faculty of PharmacyDepartment of Analytical Chemistry Cairo university Faculty of PharmacyDepartment of Analytical Chemistry

Two simple, accurate, precise and economic spectrophotometric methods have been developed for simultaneous determination of Atorvastatin calcium (ATR) and Ezetimibe (EZ) in their bulk powder and pharmaceutical dosage form. Method (I) is based on dual wavelength analysis while method (II) is the mean centering of ratio spectra spectrophotometric (MCR) method. In method (I), two wavelengths were selected for each drug in such a way that the difference in absorbance was zero for the second drug. At wavelengths 226.6 and 244 nm EZ had equal absorbance values; therefore, these two wavelengths have been used to determine ATR; on a similar basis 228.6 and 262.8 nm were selected to determine EZ in their binary mixtures. In method II, the absorption spectra of both ATR and EZ with different concentrations were recorded over the range 200-350, divided by the spectrum of suitable divisor of both ATR and EZ and then the obtained ratio spectra were mean centered. The concentrations of active components were then determined from the calibration graphs obtained by measuring the amplitudes at 215-260 nm (peak to peak) for both ATR and EZ. Accuracy and precision of the developed methods have been tested; in addition recovery studies have been carried out in order to confirm their accuracy. On the other hand, selectivities of the methods were tested by application for determination of different synthetic mixtures containing different ratios of the studied drugs. The developed methods have been successfully used for determination of ATR and EZ in their combined dosage form and statistical comparison of the developed methods with the reported spectrophotometric one using F and Student’s t-tests showed no significant difference regarding both accuracy and precision.

关键词： Atorvastatin Ezetimibe Dual wavelength method Mean centering of ratio spectra Spectrophotometry

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Physicochemical Properties of Nanocrystallite Copper Ferrite Prepared by a Novel Self Flash Combustion of Acetate Precursors

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Journal of Materials Science & Technology 2005年第5期21卷 675-680页

作者： M.H.Khedr A.A.Farghali Chemistry Department Faculty of Science(Beni-Suef Branch)Cairo UniversityBeni-Suef EgyptChemistry DepartmentFaculty of Science(Beni-Suef Branch)Cairo UniversityBeni-Suef Egypt

Copper ferrite, CuFe2O4, one of the important ferrites due to its interesting electrical, magnetic and structural properties, is obtained by a novel self flash combustion of a homogeneous mixture of one mole copper acetate monohydrate, Cu（CH3COO）2·H2O, and two moles of iron （Ⅲ） acetate basic, Fe（CHCOO）2·OH. Nanocrystalite （89 nm） Copper ferrite （less than 100%） is obtained at lower temperatures, whereas 100% copper ferrite is obtained after calcination at 1000℃. Thermal analysis （TG and DTA）, X-ray diffraction （XRD）, Fourier transform infrared spectroscopy （FTIR）, photo microscopy, magnetic and porosity obtained after calcinations at 700, 800, 900 and 1000℃ to measurements have been carried out for the specimens characterize the conversion efficiency of the powder precursors to copper ferrite. It was found that increasing temperature leads to great improvement in the magnetic properties. By increasing calcination temperature from 700～1000℃saturation magnetic flux density （Bs） increased from 17.8 to 40.8 emu/g, while remnant magnetic flux density （Br） increased from 10.1 to 17.11 emu/g.

关键词： Copper ferrite Flash combustion Synthesis Characterization Magnetic properties Microstructure

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Development of Sulfuric Acid Speleogenetic Deposits within Cavernous Middle Eocene Beds:Inference on Hydrocarbon Gas Seepages,Giza Pyramids Plateau,Egypt

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Acta Geologica Sinica(English Edition) 2021年第3期95卷 946-961页

作者： Hanan S.BADAWY Geology Department Faculty of ScienceBeni-Suef UniversityBeni-SuefEgypt

Development of sulfuric acid speleogenetic mineral deposits within cavernous middle Eocene beds of the Pyramids plateau is linked to hydrocarbon gas *** work carried out field observations,binocular,polarizing,scanning and transmitted electron microscopy investigation,X-ray diffraction and X-ray fluorescence *** morphological and petrographic features and chemical composition of the studied mineral deposits reveal a hypogene sulfuric acid speleogenesis.A model comprised of the following stages can be used to explain the presence of these features.(1)Ascent of hydrogen sulfide(H_(2)S)gas associated with hydrocarbon seepages from the Cretaceous reservoirs under reducing conditions followed by oxidation to sulfuric acid(H_(2)SO_(4)),(2)descent of carbonic acid(H_(2)CO_(3))-rich solution generated from surface sources,(3)reaction of H_(2)SO_(4)and H_(2)CO_(3)with the calcareous and argillaceous host rocks,(4)formation of H_(2)SO_(4)speleogenetic by-products represented by natroalunite,aluminium-phosphate-sulfate,hydrated halloysite and Fe/Mn oxides within the replacive gypsum,and(5)subsequent stresses due to the formation of nearby stratiform cavities gave rise to the development of fractures/veinlets filled with displacive fibrous satinspar *** study sets the paleokarst features of the Giza Pyramids plateau within a hypogene sulfuric acid karst system developed by the action of groundwater containing H_(2)S,H_(2)SO_(4)and H_(2)CO_(3).

关键词： karstification natroalunite aluminium-phosphate-sulfate hydrated halloysite enterolithic growth satinspar gypsum

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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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Finite Groups with Certain S-Permutable and GS-Maximal Subgroups

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Algebra Colloquium 2020年第4期27卷 661-668页

作者： A.M.Elkholy M.H.Abd-Ellatif Department of Mathematics and Computer Science Faculty of Science Beni-Suef University62511 Beni-SuefEgypt

Let G be a finite group and H a subgroup of *** say that H is S-permutable in G if H permutes with every Sylow subgroup of G.A group G is called a generalized smooth group(GS-group)if[G/L]is totally smooth for every subgroup L of G of prime *** this paper,we investigate the structure of G under the assumption that each subgroup of prime order is S-permutable if the maximal subgroups of G are GS-groups.

关键词： smooth groups subgroup lattices S-permutability

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Rudists(Bivalvia) from a Cretaceous Platform in Northern Egypt: Taxonomy and Paleobiogeography

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Acta Geologica Sinica(English Edition) 2021年第6期95卷 1967-1983页

作者： Yasser SALAMA Jamaan S.AJAREM Ahmed A.ALLAM Ahmed M.ALMALKI Geology Department Faculty of ScienceBeni-suef UniversityBeni-suef 65211Egypt Department of Zoology College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia Department of Zoology Faculty of ScienceBeni-suef UniversityBeni-suef 65211Egypt

New well-preserved rudist materials come from the Barremian–Turonian marine formations in the Yelleg, Minsherah, Maaza, and Raghawi sections in North Sinai, northern Egypt. There, 17 discovered rudist species belonging to 13 genera and seven taxonomic families are described in detail as follows: Eoradiolites plicatus(Conrad), Eoradiolites liratus(Conrad), Praeradiolites ponsianus(d'Archiac), Archaeoradiolites sp., Bournonia africana Douvillé, Bournonia fourtaui Douville, Biradiolites lombricalis(d'Orbigny), Biradiolites zumoffeni Douville, Radiolites lewyi lewyi Parnes, Radiolites sauvagesi(d'Hombres-Firmas), Durania arnaudi(Choffat), Toucasia carinata(Matheron), Toucasia sp., Neocaprina raghawiensis Steuber and Bachmann, Sellaea sp., Ichthyosarcolites sp. and Horoiopleura sp.. The Cenomanian deposits in the northern Eastern desert of Egypt only contain E. liratus. The domination of the Cenomanian rudist species in North Sinai, however, is attributed to changes in the platform, which passes mainly from carbonate in the north to siliciclastics in the south. The presence of Horiopleura sp. in the late Barremian-early Aptian deposits is documented for the first time, which suggests the expansion of taxa of the genus Horiopleura Douville to North Sinai during this interval. The age of the rudist species is documented from the late Barremian-Turonian formations, with their geographic distribution in the Mediterranean region considered..

关键词： invertebrate paleontology mollusks rudists Taxonomy Paleobiogeography Barremian–Turonian Egypt

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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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Preparation and characterization of (CeO2)x-(Fe2O3)1-x nanocomposites:reduction kinetics and hydrogen storage

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Rare Metals 2020年第3期39卷 218-229页

作者： Shimaa G.Sayed Waleed M.A.El Rouby Ahmed A.Farghali Materials Science and Nanotechnology Department Faculty of Postgraduate Studies for Advanced Science(PSAS)Beni-Suef UniversityBeni Suef62511Egypt

A series of nanosized CeO2-Fe2O3 mixed-oxide nanocomposites with different Ce4+/Fe3+molar ratios were successfully prepared by a co-precipitation *** surface area increased with Fe2O3 content increasing up to 60 wt%in the ***,with further increase in Fe2O3 content,the surface area began to *** reduction processes of the CeO2-Fe2O3 nanocomposites were studied in a hydrogen atmosphere at 300-600℃.The reduction rates increased by increasing both the temperature and Fe2O3 content in the *** microstructure of the reduced composites at 500℃illustrated the presence of a considerable number of macro-and *** activation energy values were calculated which were in the range of 3.56-5.37 kJ mol-1 at the initial stages(up to 35%reduction)and 5.21-10.2 kJ·mol-1 at the final stages(up to 80%reduction)of *** rate-controlling mechanisms in both the initial and final reduction stages were determined,and the initial reaction stage was controlled by combined gaseous diffusion and interfacial chemical reaction mechanisms for all the composites except for pure CeO2,which was controlled by a chemical reaction *** final reaction stage was controlled by a gaseous diffusion mechanism for some composites,while for the others it was controlled by combined gaseous diffusion and interfacial chemical reaction *** hydrogen sorption properties of the nanocomposites were studied by pressure composition isotherms using a volumetric *** storage in the nanocomposites increased by increasing the temperature because of the formation of oxygen vacancies which enhance atomic H adsorption and function as strong adsorption sites forming more metal hydride covalent bonds.

关键词： CeO2-Fe2O3 nanocomposite Reduction kinetics Reduction mechanism Hydrogen storage Oxygen vacancies

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Some Factorization Properties in A+B[Г^(*)]Domains

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Algebra Colloquium 2020年第3期27卷 643-650页

作者： E.Boulayat S.El Baghdadi Department of Mathematics Beni Mellal University FSTP.O.Box 523Beni MellalMorocco

Let A■B be an extension of integral domains andГa commutative,additive,cancellative,torsion-free monoid with T∩-Г={0}.Let B[Г]be the semigroup ring ofГover B and setГ^(*)=Г\{0}.Then R=A+B[Г^(*)]is a subring of B[Г].We investigate various factorization properties which are weaker than unique factorization in the domainsof the form A+B[Г^(*)].

关键词： monoid factorization atomic ACCP BFD

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Effectiveness and safety of subthreshold vibration over suprathreshold vibration in treatment of muscle fatigue in elderly people

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World Journal of Clinical Cases 2023年第15期11卷 3434-3443页

作者： Ayman A Mohamed Esra Khaled Asma Hesham Ahmed Khalf Physical Therapy Nahda UniversityBeni Suef 23435Egypt Physical Therapy Beni-Suef UniversityBeni Suef 32456Egypt

Muscle fatigue is common in many populations,particularly *** increases the incidence of muscle fatigue and delays its *** is a huge debate about the current treatments for muscle fatigue,particularly in ***,it has been discovered that mechanoreceptors have an important role as a sensory system in sensing muscle fatigue which could enhance the body's response to muscle *** function of mechanoreceptors could be enhanced by applying either suprathreshold or subthreshold *** suprathreshold vibration improves muscle fatigue,it can cause desensitization of cutaneous receptors,discomfort,and paresthesia,which are barriers to clinical *** vibration has been approved as a safe and effective method of training for mechanoreceptors;however,its use and effectiveness in muscle fatigue have never been tested or *** physiological effects of subthreshold vibration in the treatment of muscle fatigue include:(1)Enhancing the function of mechanoreceptors themselves;(2)Increasing the firing rate and function of alpha motor neurons;(3)Increasing blood flow to fatigued muscles;(4)Decreasing the rate of muscle cell death in elderlies(sarcopenia);and(5)Driving motor commands and allow better performance of muscles to decrease fatigue *** conclusion,the use of subthreshold vibration could be a safe and effective treatment for muscle fatigue in *** could enhance recovery from muscle ***,Subthreshold Vibration is safe and effective in treating muscle fatigue in comparison to suprathreshold vibration.

关键词： Subthreshold Vibration Muscle Fatigue Elderly people

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