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添加TiO_2和ZrO_2对火焰热喷涂Al_2O_3涂层性能的影响（英文）

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Transactions of Nonferrous Metals Society of China 2016年第5期26卷 1345-1352页

作者： Rassim YOUNES Mohand Amokrane BRADAI Abdelhamid SADEDDINE Youcef MOUADJI Ali BILEK abderrahim benabbas Laboratory of Mechanics Materials and Energetic Faculty of Technology University of Bejaia Laboratory of Mechanics Faculty of Engineering Sciences Campus Chaabet-ErsasUniversity of Constantine Mechanical Laboratory of Structure and Energetic Mechanical Engineering DepartmentUniversity of Tizi-Ouzou Laboratory Processes for Materials Energy Water and Environment Faculty of Science and TechnologyUniversity of Bouira

采用火焰热喷涂技术在低碳钢表面上沉积制备添加25%ZrO_2(简称AZ-25)和3%TiO_2(简称AT-3)增强体的Al_2O_3涂层,对涂层的显微组织、相组成、显微硬度和摩擦学性能进行了研究。X射线衍射(XRD)结果表明,AT-3涂层的主要相组成为α-Al_2O_3,... 详细信息

采用火焰热喷涂技术在低碳钢表面上沉积制备添加25%ZrO_2(简称AZ-25)和3%TiO_2(简称AT-3)增强体的Al_2O_3涂层,对涂层的显微组织、相组成、显微硬度和摩擦学性能进行了研究。X射线衍射(XRD)结果表明,AT-3涂层的主要相组成为α-Al_2O_3,此外还含有一些亚稳的β-Al_2O_3和κ-Al_2O_3相。而AZ-25涂层的主要相组成为α-Al_2O_3,还有一些q-ZrO_2和m-ZrO_2相。在大多数实验条件下,AT-3涂层的摩擦学性能(摩擦因数、磨损率)均比AZ-25涂层要好。添加ZrO_2增强体会导致涂层的显微硬度降低,而添加TiO_2会使涂层硬度增加。

关键词：热喷涂涂层增强体摩擦因数磨损率

热处理对火焰喷涂Fe–Ni–Al合金涂层组织和摩擦性能的影响（英文）

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Journal of Central South University 2018年第3期25卷 473-481页

作者： Youcef Mouadji Mohand Amokrane Bradai Rassim Younes Abdelhamid Sad-eddine abderrahim benabbas National Polytechnic School of Constantine Department of Mechanical Engineering University of Constantine Laboratory of Mechanics Materials and Energetic Faculty of Technology University of Bejaia Laboratory Processes for Materials Energy Water and Environment Faculty of Science and TechnologyUniversity of Bouira

采用火焰喷涂技术在E335钢上制备粉末状Fe基涂层。研究了后续热处理对涂层组织和力学性能的影响。在623 K、823 K和1023 K的空气中对涂层进行后续热处理1 h,然后随炉在空气中冷却。结果表明,随着退火温度的升高,823 K和1023 K处理后涂... 详细信息

采用火焰喷涂技术在E335钢上制备粉末状Fe基涂层。研究了后续热处理对涂层组织和力学性能的影响。在623 K、823 K和1023 K的空气中对涂层进行后续热处理1 h,然后随炉在空气中冷却。结果表明,随着退火温度的升高,823 K和1023 K处理后涂层的微观结构发生了如下变化:孔隙率降低,碳化物和氧化物形成。在623 K时,涂层的主要相为固溶体FCC(Fe,Ni)、金属间化合物AlFe_3和碳化物[Fe,C];碳化铁、碳化钼和氧化铁Fe_3O_4作为主要相增强了823 K退火涂层中的固溶体FCC(Fe,Ni)相;但在1023 K处理涂层中观察到碳化钼和氧化物Fe_3O_4消失了。823 K退火涂层的耐磨性优于623 K和1023 K退火涂层,其磨损率最低。

关键词：热喷涂涂层后续热处理显微组织磨损

Gender-Based Analysis of User Reactions to Facebook Posts

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Big Data Mining and Analytics 2024年第1期7卷 75-86页

作者： Yassine El Moudene Jaafar Idrais Rida El Abassi abderrahim Sabour Mathematical Engineering and Computer Science Laboratory Faculty of SciencesIbn Zohr UniversityAgadir 8706Morocco Department of Computer Science Mathematical−High School of Technology Ibn Zohr UniversityAgadir 8706Morocco

Online Social Networks(OSNs)are based on the sharing of different types of information and on various interactions(comments,reactions,and sharing).One of these important actions is the emotional reaction to the *** diversity of reaction types available on Facebook(namely FB)enables users to express their feelings,and its traceability creates and enriches the users’emotional identity in the virtual *** paper is based on the analysis of 119875012 FB reactions(Like,Love,Haha,Wow,Sad,Angry,Thankful,and Pride)made at multiple levels(publications,comments,and sub-comments)to study and classify the users’emotional behavior,visualize the distribution of different types of reactions,and analyze the gender impact on emotion *** of these can be achieved by addressing these research questions:who reacts the most?Which emotion is the most expressed?

关键词： profiling knowledge extraction data mining emotion mining social media data crawling Facebook reactions gender

Graphite Carbone Structure

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Crystal Structure Theory and Applications 2024年第1期12卷 1-10页

作者： Lahbib Abbas Lahcen Bih Khalid Yamni abderrahim Elyahyaouy Abdelmalik El Attaoui Zahra Ramzi Materials Membranes and Nanotechnology Laboratory Faculty of Science and Technology Moulay Ismail University Errachidia Morocco Engineering Sciences and Professions Laboratory National School of Arts and Crafts Moulay Ismail University Meknes Morocco Materials Membranes and Nanotechnology Laboratory Chemistry Department Faculty of Sciences Moulay Ismail Univer-sity Meknes Morocco Physics Department Faculty of Sciences Ibn Tofail University Kenitra Morocco Laboratory of Molecular Chemistry Materials and Environment (LCM2E) Multidisciplinary Faculty of Nador Mohamed 1st University Nador Morocco Laboratory of SCiMATOP Chemistry Department Faculty of Sciences Semlalia Cadi Ayyad University Marrakech Morocco

Carbon graphite is a crystalline form of carbon consisting of layers of hexagonal carbon atoms arranged in a two-dimensional “graphene” structure. Graphene layers are stacked on top of each other, forming a three-dimensional structure with a high degree of anisotropy. The carbon atoms within each layer are linked together by strong covalent bonds, creating a strong, stable lattice structure. However, the layers themselves are held together by weak van der Waals forces, enabling them to slide easily over each other. The properties of carbon graphite are highly dependent on the orientation and alignment of the graphene layers. When the layers are aligned parallel to each other, the material exhibits high strength and stiffness along the alignment direction, but is weaker and more flexible in other directions. Carbon graphite is used in a variety of applications where high strength, rigidity and electrical conductivity are required. Some common applications include electrical contacts, electric motor brushes, and as a structural material in aerospace and defense applications. The aim of our work is to describe the structure of graphite, its physical and chemical properties and its applications.

关键词： Graphite Graphene Hexagonal Structure Hardness Rigidity Electrical Con-ductivity

Determination of Latent Heats of Vaporization and Fusion

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Advances in Chemical Engineering and Science 2024年第3期14卷 113-124页

作者： Lahbib Abbas Lahcen Bih Khalid Yamni abderrahim Elyahyaouy Abdelmalik El Attaoui Zahra Ramzi Chemistry Department Faculty of Science and Technology Moulay Ismail University Meknes Er-Rachidia Morocco Engineering Sciences and Professions Laboratory National School of Arts and Crafts Moulay Ismail University Meknes Meknes Morocco Materials Membranes and Nanotechnology Chemistry Department Faculty of Sciences Moulay Ismail University Meknes Zitoune Mekns Morocco Physics Department Faculty of Sciences Ibn Tofail University Kenitra Morocco Laboratory of Molecular Chemistry Materials and Environment (LCM2E) Multidisciplinary Faculty of Nador Mohamed 1st University Oujda Nador Morocco Laboratory of SCiMATOP Chemistry Department Faculty of Sciences Semlalia Cadi Ayyad University Marrakech Morocco

Water is the most abundant liquid on the surface of the earth. It is a liquid whose properties are quite surprising, both as a pure liquid and as a solvent. Water is a very cohesive liquid: its melting and vaporization temperatures are very high for a liquid that is neither ionic nor metallic, and whose molar mass is low. Thus, water remains liquid at atmospheric pressure up to 100C while similar molecules such as H2S, H2Se, H2Te for example would give a vaporization temperature close to 80C. This cohesion is in fact ensured by hydrogen bonds between water molecules. This type of bonds between neighboring molecules, hydrogen bonds, is quite often found in chemistry [1] [2]. Any change in the state of aggregation of a substance occurs with the absorption or release of a certain amount of latent heat of transformation. Latent heat of fusion, vaporization or sublimation is the ratio of the energy supplied as heat to the mass of the substance that is melted, vaporized or sublimated. As a result of the reversibility of the processes, the fusion heat is equal to the heat released in the reverse process: crystallization and solidification heat. And likewise the heat of vaporization is equal to the heat of condensation. This equality of heat is often used to determine experimentally either of these quantities. There are two main measurement methods: 1) Direct measurement using the calorimeter, 2) Indirect measure based on the use of the VantHoff relationship. The objective of this work is to measure the latent heat of water vaporization and verify the compatibility of the experimental values with the values given by the tables using the indirect method.

关键词： Latent Heat of Vaporization Latent Heat of Fusion Calorimetry Relationship of Vant’Hoff

Systematic Method for Constructing Lewis Representations

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Open Journal of Inorganic Chemistry 2024年第1期14卷 1-18页

作者： Lahbib Abbas Lahcen Bih Khalid Yamni abderrahim Elyahyaouy Abdelmalik El Attaoui Zahra Ramzi Materials Membranes and Nanotechnology Faculty of Science and Technology Moulay Ismail University Meknes Er-Rachidia Morocco Engineering Sciences and Professions Laboratory National School of Arts and Crafts Moulay Ismail University Meknes Meknes Morocco Materials Membranes and Nanotechnology Chemistry Department Faculty of Sciences Moulay Ismail University Meknes Meknes Morocco Physics Department Faculty of Sciences Ibn Tofail University Kenitra Morocco Laboratory of Molecular Chemistry Materials and Environment (LCM2E) Multidisciplinary Faculty of Nador Mohamed 1st University Oujda Nador Morocco Laboratory of SCiMATOP Chemistry Department Faculty of Sciences Semlalia Cadi Ayyad University Marrakech Morocco

The systematic method for constructing Lewis representations is a method for representing chemical bonds between atoms in a molecule. It uses symbols to represent the valence electrons of the atoms involved in the bond. Using a number of rules in a defined order, it is often better suited to complicated cases than the Lewis representation of atoms. This method allows us to determine the formal charge and oxidation number of each atom in the edifice more efficiently than other methods.

关键词： Systematic Method Lewis Representation Chemical Bond Formal Charge Oxidation Number

Ectopic Cornual Pregnancy: Case Report

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Open Journal of Obstetrics and Gynecology 2024年第5期14卷 847-854页

作者： Karim Lakraimi Myriem Sali Bouchra Fakhir abderrahim Aboulfallah Hamid Asmouki Karam Harou Ahlam Bassir Abderraouf Soummani Department of Obstetrics and Gynecology Med VI Mother and Child University of Cadi Ayyad Marrakech Morocco

This article showcases a clinical case of ectopic pregnancy lodged in the cornual. A pregnancy implanted in this location is a rarity, making it difficult to diagnose. By describing this case and screening of the literature, we explain the various diagnostic and therapeutic methods, both medical and surgical. Highlighting the importance of conservative treatment flush with the uterine horn, and conclude with some practical recommendations.

关键词： Horn Pregnancy Ultrasound Examination Laparotomy

Effect of an Inclined Slots on the Power Consumption and Vortices Size in a Rushton Turbine Agitated Tank

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Chinese Journal of Mechanical Engineering 2023年第6期36卷 261-276页

作者： Sarra Youcefi Mohamed Bouzit Abdelkader Youcefi abderrahim Mokhefi Laboratory of Applied Mechanics Department of Mechanical EngineeringUniversity of Sciences and Technology of OranOran 31000Algeria Laboratory of Maritime Sciences and Engineering Department of Marine EngineeringUniversity of Science and Technology of OranOran 31000Algeria Laboratory of Aeronautics and Propulsion Systems Department of Mechanical EngineeringUniversity of Science and Technology of OranOran 31000Algeria Laboratory of Mechanics Modeling and ExperimentationDepartment of Mechanical EngineeringTahri Mohamed University of BecharBechar 08000Algeria

Mechanical agitation in baffled vessels with turbines plays a vital role in achieving homogeneous fluid mixing and promoting various transfer ***,designing vessels with optimal energy efficiency and flow dynamics is essential to enhance operational performance and eliminate flow ***,the present research focuses on a numerical investigation of the impact of inclined slots with different angles installed at the side-wall of a cylindrical vessel equipped with a Rushton *** study explores power consumption and vortex size while considering various rotation directions of the impeller with different rotation *** numerical simulations are conducted for Reynolds numbers ranging from 104 to 105,using the RANS k-εturbulence model to govern the flow inside the stirred vessel,accounting for mass and momentum *** results have shown that the installation of slots reduces power consumption and vortex size compared to conventional vessel ***,increasing the slot angle from 0 to 32.5°further reduces energy consumption and vortex size,especially with negative rotation *** the other hand,increasing the Reynolds numbers leads to a decrease in power consumption and an increase in vortex *** present research therefore proposes a design for con-structing Rushton-turbine stirred vessels offering optimal operation,characterized by reduced energy consumption and minimized vortex size.

关键词： Mixing Stirred tank Rushton turbine Inclined slots Hydrodynamic Power consumption Vortices size

Numerical modeling of ZnSnO/CZTS based solar cells

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Optoelectronics Letters 2022年第5期18卷 276-282页

作者： Assiya Haddout Mounir Fahoume abderrahim Raidou Mohamed Lharch Materials and Subatomic Physics Laboratory Faculty of SciencesIbn Tofail UniversityB.P 133Kenitra14000Morocco

Numerical simulation has been performed to improve the performance of Cu_(2)ZnSnS_(4)(CZTS)solar cells by replacing CdS with Zn_(1−x)Sn_(x)O buffer *** influences of thickness,donor concentration and defect density of buffer layers on the performance of CZTS solar cells were *** has been found that Zn_(1−x)Sn_(x)O buffer layer for Sn content of 0.20 is better for CZTS solar cell.A higher efficiency can be achieved with thinner buffer *** optimized solar cell demonstrated a maximum power conversion efficiency of 13%.

关键词： CZTS donor solar