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Synthesis of Certain 3-Aminopyrazolo[5,4-b]pyridine and 3,4-Substituted Pyrido[2′,3′：3,4]pyrazolo[5,1-c][1,2,4]triazine Derivatives

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Chinese Journal of Chemistry 2007年第12期25卷 1887-1891页

作者： EL-LOUH, ali Khader Khalil ABUNADA, Nada mohamed EL-SHOUBAKI, mohamed Chemistry Department Faculty of Science Al-Azhar University-Gaza Gaza 76888 Palestine Chemistry Department Faculty of Applied Sciences Al-Aqsa University Gaza Palestine 4051 Israel

2-Thioxo-1,2-dihydropyridine derivatives 2a, 2b were reacted with methyl iodide to give 2-methylthiopyridines 3a, 3b, which were reacted with hydrazine hydrate to produce 3-aminopyrazolo[5,4-b]pyridines 4a, 4b. Compounds 4a, 4b were diazotized to afford the corresponding diazonium salts 5a, 5b, which were reacted with some active methylene compounds 6a-6h to give the corresponding pyrido[2′,3′ ： 3,4]pyrazole[5,1-c][1,2,4]triazines 7-14.

关键词： pyrazolo[3,4-b]pyridine pyrido[2′,3′ : 3,4]pyrazole[5 1-c] [ 1,2,4]triazine 2-arylmethylidene-2-cyanothioacetamine 2-thioxopyridine

Electrospinning of Nylon-6,6 Solutions into Nanofibers: Rheology and Morphology Relationships

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Chinese Journal of Polymer Science 2014年第6期32卷 793-804页

作者： ali Abbasi mohamed Mahmoud Nasef Matsuura Takeshi Reza Faridi-Majidi Faculty of Chemical Engineering Universiti Teknologi Malaysia Institute of Hydrogen Economy International Campus Universiti Teknologi Malaysia Malaysia-Japan International Institute of Technology International Campus Universiti Teknologi Malaysia Department of Chemical & Biological Engineering University Ottawa Department of Medical Nanotechnology School of Advanced Medical Technologies Tehran University of Medical Sciences

The relationship between the rheological properties of nylon-6,6 solutions and the morphology of their electrospun nanofibers was established. The viscosity of nylon-6,6 in formic acid （90%） was measured in the concentration range of 5 wt%-25 wt% using a programmable viscometer. Electrospinning of nylon-6,6 solutions was carried out under controlled parameters. The chemical structure, morphology and thermal properties of the obtained nanofibers were investigated using Fourier transform infrared spectroscopy （FTIR）, scanning electron microscopy （SEM） and differential scanning calorimetry （DSC）, respectively, Entanglement concentration （ce） was found to be 15 wt% and a power law relationship between specific viscosity and solution concentration was observed with exponents of 2.0 and 3.3 for semi-dilute unentangled （c 〈 ce） and semi-dilute entangled （c 〉 ce） regimes, respectively. The diameter and uniformity of the nanofibers were found to be dependent on the viscosity. Moreover, the average diameter of electrospun nanofibers was found to be dependent on zero shear rate viscosity and normalized concentration （c/ce） in a power law relationship with exponents of 0.298 and 0.816, respectively. For nylon-6,6 solutions, the entanglement concentration （ce = 15 wt%） provides the threshold viscosity required for the formation of a stable polymeric jet during electrospinning and producing uniform beadless fibers. For concentrations less than ce, beaded fibers with some irregularities are formed. DSC analysis showed an increase in crystallinity of all electrospun samples compared to original polymer. Furthermore; Based on FTIR spectroscopy, α phase is dominant in electrospun nanofibers and minor amount offland ）,phases is also available.

关键词： Nylon-6,6 electrospinning Viscosity Nanofibers Entanglement concentration Crystallinity.

Cooperative Answering of Fuzzy Queries

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Journal of Computer Science & Technology 2009年第4期24卷 675-686页

作者： Narjes Hachani mohamed ali Ben Hassine Hanene Chettaoui Habib Ounelli Department of Computer Sciences Faculty of Sciences of Tunis University Campus Tunis 1060 Tunisia

The majority of existing information systems deals with crisp data through crisp database systems. Traditional Database Management Systems （DBMS） have not taken into account imprecision so one can say there is some sort of lack of flexibility. The reason is that queries retrieve only elements which precisely match to the given Boolean query. That is, an element belongs to the result if the query is true for this element; otherwise, no answers are returned to the user. The aim of this paper is to present a cooperative approach to handling empty answers of fuzzy conjunctive queries by referring to the Formal Concept Analysis （FCA） theory and fuzzy logic. We present an architecture which combines FCA and databases. The processing of fuzzy queries allows detecting the minimal reasons of empty answers. We also use concept lattice in order to provide the user with the nearest answers in the case of a query failure.

关键词： cooperative system database empty answer formal concept analysis fuzzy query

Nonlinear Coordinated Passivation Control of Single Machine Infinite Bus Power System with Static Var Compensator

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Journal of Modern Power Systems and Clean Energy 2021年第6期9卷 1557-1565页

作者： Salma Keskes Souhir Salleem Larbi Chrifi-Alaoui mohamed Ben ali Kammoun Electric Machines and Power Networks Control Laboratory from the Electrical Engineering Department National Engineering School of Sfax Innovative Technologies Laboratory University of Picardy Jules Verne

We propose a nonlinear coordinated control of the generator excitation and the static var compensator(SVC) in order to enhance the transient stability and voltage regulation of power system by the passivation approach. SVC is installed in the middle of the transmission line of power system and consists of a single machine infinite bus(SMIB) system. The design of the proposed controller consists of two parts. On one hand,the generator excitation controller is designed based on a backstepping controller. On the other hand, the conception of SVC control input is based on the coordinated passivation approach,which can guarantee the asymptotic stability of the closed-loop system. The simulation results show the effectiveness of the proposed controller compared with other methods, which ensures better performance than the uncoordinated control when the system is subjected to a disturbance.

关键词： Coordinated control passivation approach transient stability control design

TG-SMR:AText Summarization Algorithm Based on Topic and Graph Models

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Computer Systems Science & Engineering 2023年第4期45卷 395-408页

作者： mohamed ali Rakrouki Nawaf Alharbe Mashael Khayyat Abeer Aljohani Applied College Taibah UniversityMedina42353Saudi Arabia College of Computer Science and Engineering University of JeddahJeddah21959Saudi Arabia

Recently,automation is considered vital in most fields since computing methods have a significant role in facilitating work such as automatic text ***,most of the computing methods that are used in real systems are based on graph models,which are characterized by their simplicity and ***,this paper proposes an improved extractive text summarization algorithm based on both topic and graph *** methodology of this work consists of two ***,the well-known TextRank algorithm is analyzed and its shortcomings are ***,an improved method is proposed with a new computational model of sentence *** experimental results were carried out on standard DUC2004 and DUC2006 datasets and compared to four text summarization ***,through experiments on the DUC2004 and DUC2006 datasets,our proposed improved graph model algorithm TG-SMR(Topic Graph-Summarizer)is compared to other text summarization *** experimental results prove that the proposed TG-SMR algorithm achieves higher ROUGE *** is foreseen that the TG-SMR algorithm will open a new horizon that concerns the performance of ROUGE evaluation indicators.

关键词： Natural language processing text summarization graph model topic model

Geochemistry of an Alaskan-type mafic-ultramafic complex in Eastern Desert, Egypt:New insights and constraints on the Neoproterozoic island arc magmatism

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Geoscience Frontiers 2019年第3期10卷 941-955页

作者： Shehta E.Abdallah Shehata ali mohamed A.Obeid Geology Department Faculty of Science Zagazig University Geology Department Faculty of Science Minia University Geology Department Faculty of Science Fayoum University Faculty of Petroleum and Mining Sciences Alexandria University (Matrouh Branch)

Mikbi intrusion(MI) is a part of the Neoproterozoic Nubian Shield located along the NE-SW trending major fracture zones prevailing southern Eastern Desert of Egypt. In this study, we present for the first time detailed mineralogical and bulk-rock geochemical data to infer some constraints on the parental magma genesis and to understand the tectonic processes contributed to MI formation. Lithologically, it is composed of fresh peridotite, clinopyroxenite, hornblendite, anorthosite, gabbronorite, pyroxene amphibole gabbro, amphibole gabbro and diorite. All rocks have low Th/La ratios(mostly alies excluding significant crustal contamination. They show very low concentrations of Nb, Ta, Zr and Hf together with sub-chondritic ratios of Nb/Ta(2-15) and Zr/Hf(19-35),suggesting that their mantle source was depleted by earlier melting extraction event. The oxygen fugacity(logfO_2) estimated from diorite biotite is around the nickel-nickel oxide buffer(NNO) indicating crystallization from a relatively oxidized magma. Amphiboles in the studied mafic-ultramafic rocks indicate relative oxygen fugacity(i.e. ΔNNO; nickel-nickel oxide) of 0.28-3 and were in equilibrium mostly with 3.77-8.24 wt.% H_2 O_(melt)(i.e. water content in the melt), consistent with the typical values of subduction-related magmas. Moreover, pressure estimates(0.53-6.79 kbar) indicate polybaric crystallization and suggest that the magma chamber(s) was located at relatively shallow crustal levels. The enrichment in LILE(e.g., Cs, Ba, K and Sr) and the depletion in HFSE(e.g., Th and Nb) relative to primitive mantle are consistent with island arc signature. The olivine, pyroxene and amphibole compositions also reflect arc affinity. These inferences suggest that their primary magma was derived from partial melting of a mantle source that formerly metasomatized in a subduction zone setting. Clinopyroxene and bulkrock data are consistent with orogenic tholeiitic affinity. Conse

关键词： Alaskan-type complex Neoproterozoic Arc magmatism Eastern desert Egypt

A Multi-Level Threshold Method for Edge Detection and Segmentation Based on Entropy

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Computers, Materials & Continua 2020年第4期63卷 1-16页

作者： mohamed A.El-Sayed Abdelmgeid A.ali mohamed E.Hussien Hameda A.Sennary Department of Mathematics Faculty of ScienceFayoum UniversityFayoumEgypt.CurrentlyComputer Science DepartmentTaif UniversityTaifSaudi Arabia Computer Science Department Faculty of Computers and Information Minia UniversityMiniaEgypt Department of Mathematics Faculty of ScienceAswan UniversityAswanEgypt

The essential tool in image processing,computer vision and machine vision is edge detection,especially in the fields of feature extraction and feature *** is a basic area in information *** entropy,in image processing field has a role associated with image *** an initial step in image processing,the entropy is always used the image’s segmentation to determine the regions of image which is used to separate the background and objects in *** segmentation known as the process which divides the image into multiple regions or sets of *** applications have been development to enhance the image *** paper utilizes the Shannon entropy to achieve edge detection process and segmentation of the *** introduces a new method of edge detection for 2-D histogram and Shannon entropy based on multilevel *** method utilizes the gray value and the average gray value of the pixels to achieve the two dimensional *** current method has apriority in comparison to some upper classical *** experimental results exhibited that the proposed method could capture a moderate quality and execution time better than other comparative methods,particularly in the largest images *** proposed method offers good results when applied with images of different sizes from the civilization of ancient Egyptians.

关键词： Multi-level threshold edge detection 2D histogram entropy

TiO_2–PANI/Cork composite: A new floating photocatalyst for the treatment of organic pollutants under sunlight irradiation

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Journal of Environmental Sciences 2017年第10期29卷 3-13页

作者： Mouheb Sboui mohamed Faouzi Nsib ali Rayes Meenakshisundaram Swaminathan Ammar Houas Laboratory CI-Sfax Faculty of Science University of Sfax URCMEP (UR11ES85) Faculty of Sciences University of Gabès National School of Engineers (ENIG) University of Gabès High School of Sciences and Technology of Hammam Sousse University of Sousse Nanomaterials Laboratory International Research Centre Kalasalingam University Al Imam Mohammad Ibn Saud Islamic University (IMSIU) College of Sciences Department of Chemistry

A novel photocatalyst based on TiO2-PANI composite supported on small pieces of cork has been reported. It was prepared by simple impregnation method of the polyaniline（PANI）-modified TiO2 on cork. The TiO2-PANI/Cork catalyst shows the unique feature of floating on the water surface. The as-synthesized catalyst was characterized by X-ray diffraction（XRD）,scanning electron micrograph（SEM）, transmission electron microscopy（TEM）, thermogravimetric analysis（TGA）, Fourier transform infrared spectroscopy（FT-IR）, UV-vis diffuse reflectance spectra（UV-vis DRS） and the Brunauer-Emmett-Teller（BET） surface area analysis. Characterization suggested the formation of anatase highly dispersed on the cork surface. The prepared floating photocatalyst showed high efficiency for the degradation of methyl orange dye and other organic pollutants under solar irradiation and constrained conditions, i.e., no-stirring and no-oxygenation. The TiO2-PANI/Cork floating photocatalyst can be reused for at least four consecutive times without significant decrease of the degradation efficiency.

关键词： TiO2 Polyaniline Cork Floating catalyst Photodegradation Solar light

Investigation of new solutions for an extended(2+1)-dimensional Calogero-Bogoyavlenskii-Schif equation

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Frontiers of Mathematics in China 2021年第4期16卷 925-936页

作者： mohamed R.ali R.SADAT Wen-Xiu MA Department of Mathematics Faculty of EngineeringBenha UniversityEgypt Department of Mathematics Zagazig Faculty of EngineeringZagazig UniversityZagazigEgypt Department of Mathematics Zhejiang Normal UniversityJinhua 321004China Department of Mathematics King Abdulaziz UniversityJeddah 21589Saudi Arabia Department of Mathematics and Statistics University of South FloridaTampaFL33620-5700USA School of Mathematics South China University of TechnologyGuangzhou 510640China School of Mathematical and Statistical Sciences North-West UniversityMafikeng CamusPrivate Bag X2046Mmabatho 2735South Africa

We investigate and concentrate on new infinitesimal generators of Lie symmetries for an extended(2+1)-dimensional Calogero-Bogoyavlenskii-Schif(eCBS)equation using the commutator table which results in a system of nonlinear ordinary differential equations(ODEs)which can be manually *** two stages of Lie symmetry reductions,the eCBS equation is reduced to non-solvable nonlinear ODEs using different combinations of optimal Lie *** the integration method and the Riccati and Bernoulli equation methods,we investigate new analytical solutions to those *** substituting to the original variables generates new solutions to the eCBS *** results are simulated through three-and two-dimensional plots.

关键词： Extended Calogero-Bogoyavlenskii-Schif(eCBS)equation Riccati-Bernoulli equation symmetry analysis integrating factor nonlinear integrable equations