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Analysis of cerium substitution in Co-Sr based spinel ferrites for high frequency application

Journal of Rare Earths 2024年第9期42卷 1755-1763,I0005页

作者： Laura Khudaysh Inas A.ahmed Syeda Rabia Ejaz Sajjad Ahmad Khan Yasir A.Haleem Mohamed M.Ibrahim Mahmood Ali Hafiz Muhammad Tahir Farid Zeinhom M.el-Bahy Department of Physics Faculty of ScienceJazan UniversityJazan45142Saudi Arabia Department of Chemistry Faculty of ScienceKing Khalid UniversityAbha62224Saudi Arabia Department of Physics The Government Sadiq College Women UniversityBahawalpur63100Pakistan Institute of Physics Khwaja Fareed University of Engineering and Information TechnologyRahim Yar Khan64200Pakistan Department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Centre of Excellence in Solid State Physics University of the PunjabLahorePakistan Department of Physics Government CollegeTaunsa Sharif32200Pakistan Department of Chemistry Faculty of ScienceAl-Azhar UniversityNasr City11884CairoEgypt

Spinel ferrites exhibit exceptional magnetic properties,making them a distinctive class of magnetic *** sol-gel technique was utilized for the synthesis of spinel ferrites with the chemical formula Co_(0.6)Sr_(0.4)Ce_(x)Fe_(2-x)O_(4). Following that,a comprehensive X-ray diffraction analysis unveiled the crystalline cubic structure of the synthesized *** the utilization of the M-H loop approach,the ferromagnetic attributes of ferrites were assessed,and the assimilation of rare earth elements led to substantial enhancements in saturation magnetization,remanence,and *** ferrites with a high concentration of rare earth elements have improved direct current resistivity and activation *** logarithm of a material's resistance increased from 5.29 to 8.12 Ω·cm as cerium is *** a change in the amount of cerium,the activation energy goes up from 0.19 to *** changing the frequency from 5.5 to 9.5 GHz,the dielectric characteristics were *** the frequency goes up,the dielectric constant goes *** ferrites that have been made better in every way can be used in high-frequency applications.

关键词： Activation energy DC electrical resistance Remanence magnetization Cobalt strontium spinel ferrites High frequency application Rare earths

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Numerical Investigation of Thermal Behavior of CNC Machine Tool and Its Effects on Dimensional Accuracy of Machined Parts

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Journal of Software Engineering and Applications 2024年第8期17卷 617-637页

作者： Erick Matezo-Ngoma Abderrazak el Ouafi ahmed Chebak Computer Science and Engineering Department University of Quebec Rimouski Canada GTI Mohammed VI Polytechnic University Ben Guerir Morocco

The dimensional accuracy of machined parts is strongly influenced by the thermal behavior of machine tools (MT). Minimizing this influence represents a key objective for any modern manufacturing industry. Thermally induced positioning error compensation remains the most effective and practical method in this context. However, the efficiency of the compensation process depends on the quality of the model used to predict the thermal errors. The model should consistently reflect the relationships between temperature distribution in the MT structure and thermally induced positioning errors. A judicious choice of the number and location of temperature sensitive points to represent heat distribution is a key factor for robust thermal error modeling. Therefore, in this paper, the temperature sensitive points are selected following a structured thermomechanical analysis carried out to evaluate the effects of various temperature gradients on MT structure deformation intensity. The MT thermal behavior is first modeled using finite element method and validated by various experimentally measured temperature fields using temperature sensors and thermal imaging. MT Thermal behavior validation shows a maximum error of less than 10% when comparing the numerical estimations with the experimental results even under changing operation conditions. The numerical model is used through several series of simulations carried out using varied working condition to explore possible relationships between temperature distribution and thermal deformation characteristics to select the most appropriate temperature sensitive points that will be considered for building an empirical prediction model for thermal errors as function of MT thermal state. Validation tests achieved using an artificial neural network based simplified model confirmed the efficiency of the proposed temperature sensitive points allowing the prediction of the thermally induced errors with an accuracy greater than 90%.

关键词： CNC Machine Tool Dimensional Accuracy Thermal Errors Error Modelling Numerical Simulation Finite element Method Artificial Neural Network Error Compensation

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Thermo-Physical Potential of Recycled Banana Fibers for Improving the Thermal and Mechanical Properties of Biosourced Gypsum-Based Materials

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Journal of Renewable Materials 2024年第4期12卷 843-867页

作者： Youssef Maaloufa Soumia Mounir Sara Ibnelhaj Fatima Zohra el Wardi Asma Souidi Yakubu Aminu Dodo Malika Atigui Mina Amazal Abelhamid Khabbazi Hassan Demrati ahmed Aharoune National School of Architecture Agadir New ComplexIbn Zohr UniversityAgadirMorocco Energy Materials and Sustainable Development(EMDD)Center for WaterNatural ResourcesEnvironment and Sustainable Development(CERNE2D)Mohammed V UniversityRabatMorocco Thermodynamics and Energetics Laboratory Faculty of ScienceIbn Zohr UniversityAgadirMorocco Architectural Engineering Department Najran UniversityNajranSaudi Arabia The Centre of Scientific and Engineering Research Najran UniversityNajranSaudi Arabia Physics Department LPMAT LaboratoryFaculty of Sciences Ain ChockHassan II UniversityCasablancaMorocco

The development of bio-sourced materials is essential to ensuring sustainable construction;it is considered a locomotive of the green ***,it is an abundant material in our country,to which very little attention is being *** work aims to valorize the waste of the trunks of banana trees to be used in ***,the physicochemical properties of the fiber,such as the percentage of crystallization and its morphology,have been determined by X-ray diffraction tests and scanning electron microscopy to confirm the potential and the impact of the mode of drying on the quality of the banana fibers,with the purpose to promote the use of this material in ***,the results obtained with the gypsum matrix allowed us to note a preponderant improvement in the composite’s thermal properties thanks to the variation of the banana fiber ***,the impact of the nature of the banana fiber distribution(either fiber mixed in matrix or fiber series model)on the flexural and compressive strengths of the composites was *** results obtained indicate that the insulation gain reaches up to 40%.It depends on the volume fraction and type of distribution of the banana ***,the thermal inertia of the composites developed,represented by thermal diffusivity and thermal effusivity,was *** indicate a gain of 40%and 25%,respectively,in terms of thermal diffusivity and thermal effusivity of the developed composites compared to plaster *** the mechanical properties,the flexural strength depends on the percentage of the volume fraction of banana fibers used,and it can reach 20%more than the flexural strength of plaster;nevertheless,there is a significant loss in terms of the compressive strength of the studied *** results obtained are confirmed by the microstructure of the fiber *** fact,the morphology of the banana fibers was improved by the drying *** reduces the amorphous area an

关键词： Biosourced materials fiber banana flexural strength mechanical properties open-air drying plaster thermal properties waste management

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Optimizing Grey Wolf Optimization: A Novel Agents’ Positions Updating Technique for Enhanced Efficiency and Performance

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Open Journal of Optimization 2024年第1期13卷 21-30页

作者： Mahmoud Khatab Mohamed el-Gamel ahmed I. Saleh Asmaa H. Rabie Atallah el-Shenawy Department of Mathematics and Engineering Physics Faculty of Engineering Mansoura University Mansoura Egypt Department of Computers and Control Faculty of Engineering Mansoura University Mansoura Egypt Department of Mathematics Faculty of Science New Mansoura University Mansoura Egypt

Grey Wolf Optimization (GWO) is a nature-inspired metaheuristic algorithm that has gained popularity for solving optimization problems. In GWO, the success of the algorithm heavily relies on the efficient updating of the agents’ positions relative to the leader wolves. In this paper, we provide a brief overview of the Grey Wolf Optimization technique and its significance in solving complex optimization problems. Building upon the foundation of GWO, we introduce a novel technique for updating agents’ positions, which aims to enhance the algorithm’s effectiveness and efficiency. To evaluate the performance of our proposed approach, we conduct comprehensive experiments and compare the results with the original Grey Wolf Optimization technique. Our comparative analysis demonstrates that the proposed technique achieves superior optimization outcomes. These findings underscore the potential of our approach in addressing optimization challenges effectively and efficiently, making it a valuable contribution to the field of optimization algorithms.

关键词： Grey Wolf Optimization (GWO) Metaheuristic Algorithm Optimization Problems Agents’ Positions Leader Wolves Optimal Fitness Values Optimization Challenges

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Improved Manta Ray Foraging Optimizer-based SVM for Feature Selection Problems:A Medical Case Study

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Journal of Bionic Engineering 2024年第1期21卷 409-425页

作者： Adel Got Djaafar Zouache Abdelouahab Moussaoui Laith Abualigah ahmed Alsayat Faculty of informatics University of Science and Technology Houari BoumedieneAlgiersAlgeria LRIA Laboratory University of Science and Technology Houari BoumedieneAlgiersAlgeria Computer Science Department University of Mohamed El Bachir El IbrahimiBordj Bou ArreridjAlgeria Computer Science Department University of Ferhat AbbasSetifAlgeria Computer Science Department Prince Hussein Bin Abdullah Faculty for Information TechnologyAl al-Bayt UniversityMafraq 25113Jordan Department of Computer Science College of Computer and Information SciencesJouf UniversityJoufSaudi Arabia Department of electrical and Computer Engineering Lebanese American University13-5053ByblosLebanon Hourani Center for Applied Scientific Research Al-Ahliyya Amman UniversityAmman 19328Jordan MEU Research Unit Middle East UniversityAmman 11831Jordan Applied science research center Applied science private universityAmman 11931Jordan School of Computer Sciences Universiti Sains Malaysia11800 PenangMalaysia School of Engineering and Technology Sunway University Malaysia27500 Petaling JayaMalaysia

Support Vector Machine(SVM)has become one of the traditional machine learning algorithms the most used in prediction and classification ***,its behavior strongly depends on some parameters,making tuning these parameters a sensitive step to maintain a good *** the other hand,and as any other classifier,the performance of SVM is also affected by the input set of features used to build the learning model,which makes the selection of relevant features an important task not only to preserve a good classification accuracy but also to reduce the dimensionality of *** this paper,the MRFO+SVM algorithm is introduced by investigating the recent manta ray foraging optimizer to fine-tune the SVM parameters and identify the optimal feature subset *** proposed approach is validated and compared with four SVM-based algorithms over eight benchmarking ***,it is applied to a disease Covid-19 *** experimental results show the high ability of the proposed algorithm to find the appropriate SVM’s parameters,and its acceptable performance to deal with feature selection problem.

关键词： Support vector machine Parameters tuning Feature selection Bioinspired algorithms Manta ray foraging optimizer

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Numerical Modeling and Technico-Economic Analysis of a Hybrid Energy Production System for Self-Consumption: Case of Rural Area in the Comoros

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Journal of Power and Energy Engineering 2024年第5期12卷 24-59页

作者： Fahad Maoulida Mohamed Aboudou Kassim Rabah Djedjig ahmed Ihlal Mohammed el Ganaoui LERMAB Laboratory of Studies and Research on Wood Material IUT of Longwy University of Lorraine Cosnes-et-Romain Longwy France LEMA Energy and Applied Mechanics Laboratory Faculty of Sciences and Techniques University of Comoros Moroni Comoros IREMIS Institute University of Mayotte Mayotte France LMER Laboratory of Materials and Renewable Faculty of Sciences University Ibn Zohr BP Agadir Morocco

This study aims to provide electricity to a remote village in the Union of Comoros that has been affected by energy problems for over 40 years. The study uses a 50 kW diesel generator, a 10 kW wind turbine, 1500 kW photovoltaic solar panels, a converter, and storage batteries as the proposed sources. The main objective of this study is to conduct a detailed analysis and optimization of a hybrid diesel and renewable energy system to meet the electricity demand of a remote area village of 800 to 1500 inhabitants located in the north of Ngazidja Island in Comoros. The study uses the Hybrid Optimization Model for electric Renewable (HOMER) Pro to conduct simulations and optimize the analysis using meteorological data from Comoros. The results show that hybrid combination is more profitable in terms of margin on economic cost with a less expensive investment. With a diesel cost of $1/L, an average wind speed of 5.09 m/s and a solar irradiation value of 6.14 kWh/m2/day, the system works well with a proportion of renewable energy production of 99.44% with an emission quantity of 1311.407 kg/year. 99.2% of the production comes from renewable sources with an estimated energy surplus of 2,125,344 kWh/year with the cost of electricity (COE) estimated at $0.18/kWh, presenting a cost-effective alternative compared to current market rates. These results present better optimization of the used hybrid energy system, satisfying energy demand and reducing the environmental impact.

关键词： Hybrid System Rural Area electrification Comoros Techno-Economic Analysis PV-Wind-Diesel-Battery Meteorological Data HOMER Energy Pro

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Optoelectronic and thermoelectric properties of spinel chalcogenides HgLa2X4（X=S and Se）:A first-principles study

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Journal of Rare Earths 2024年第10期 1927-1936页

作者： Aparna Dixit Inas A.ahmed Jisha Annie Abraham Zeinhom M.el-Bahy Mumtaz Manzoor Sajad Ahmad Dar Ramesh Sharma Department of Basic Science and Humanities Pranveer Singh Institute of Technology Department of Chemistry Faculty of ScienceKing Khalid University Department of Physics National Defence Academy Department of Chemistry Faculty of ScienceAl-Azhar University Institute of Physics Slovak Academy of Sciences Department of Physics Motilal Vigyan Mahavidyalya College Department of Applied Science Feroze Gandhi Institute of Engineering and Technology

We investigated spinel chalcogenides HgLa2（S/Se）4by using density function theory,and scrutinized the structural,optical,electrical,mechanical and thermoelectric transport characteristics of HgLa2（S/Se）4spinel *** enthalpy of formation,energy of cohesion,and energy volume optimum plots were used to obtain the stability as well as the perfect ground state of these *** ductility of these materials was the best illustrated with the help of Poisson's and Pugh's *** band gap results were obtained using Trans and Blaha modified Becke-Johanson potential（TB-mBJ）.Both the materials present semi-conducting nature with direct band gap equal to 1.449 and 0.892 eV respectively for HgLa2S4and *** were also made for optical characteristics with the values of dielectric function,absorption coefficient,optical conductivity,reflectivity,and refractive *** to the findings,both of these materials are suitable for infrared optoelectronic *** materials were found to have promising optoelectronic and thermoelectric applications after their optical properties and transport aspects were *** tiny levels of temperature conductivities,substantial am ounts of power conductivities,the figure of merit（more than unity）,as well as Seebecs coefficients all point to the potential use of both the materials in thermoelectric power generators.

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Rice melatonin deficiency causes premature leaf senescence via DNA methylation regulation

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The Crop Journal 2024年第3期12卷 721-731页

作者： Yue Lu ahmed Gharib Rujia Chen Hanyao Wang Tianyun Tao Zhihao Zuo Qing Bu Yanze Su Yaoqing Li Yanmo Luo Hamdi F.el-Mowafi Zhichao Wang Qianfeng Huang Shuting Wang Yang Xu Pengcheng Li Chenwu Xu Zefeng Yang Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding/Zhongshan Biological Breeding Laboratory/Key Laboratory of Plant Functional Genomics of the Ministry of Education Agriculture College of Yangzhou UniversityYangzhou 225009JiangsuChina Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops Jiangsu Key Laboratory of Crop Genetics and PhysiologyYangzhou UniversityYangzhou 225009JiangsuChina National Institute of Laser Enhanced Sciences(NILES) Cairo UniversityGiza 12613Egypt Rice Research Department Field Crops Research InstituteAgricultural Research CenterSakhaKafr El-Sheikh 33717Egypt

In a study of DNA methylation changes in melatonin-deficient rice mutants,mutant plants showed premature leaf senescence during grain-filling and reduced grain *** deficiency led to transcriptional reprogramming,especially of genes involved in chlorophyll and carbon metabolism,redox regulation,and transcriptional regulation,during dark-induced leaf *** of mCG and mCHG in the melatonin-deficient rice mutants was associated with the expression change of both protein-coding genes and transposable element-related *** in gene expression and DNA methylation in the melatonin-deficient mutants were compensated by exogenous application of melatonin.A decreased S-adenosyl-L-methionine level may have contributed to the DNA methylation variations in rice mutants of melatonin deficiency under dark conditions.

关键词： Melatonin Premature leaf senescence Rice DNA methylation Epigenetic regulation

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Catalytic Effect of Transition Metal Complexes of Triaminoguanidine on the Thermolysis of Energetic NC/DEGDN Composite

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火炸药学报 2024年第3期47卷 209-219,I0003页

作者： Mohammed Dourari ahmed Fouzi Tarchoun Djalal Trache Amir Abdelaziz Roufaida Tiliouine Tessnim Barkat Weiqiang Pang Energetic Materials Laboratory(EMLab) Teaching and Research Unit of Energetic ProcessesEcole Militaire PolytechniqueBP 17Bordj El-Bahri16046AlgiersAlgeria Xi′an Modern Chemistry Research Institute Xi′an 710065China

The transition metal complexes of triaminoguanidine(TAG-M,where M=Cobalt(Co)or Iron(Fe))have been *** catalytic effect of these complexes on the thermolysis of energetic composite based on nitrocellulose and diethylene glycol dinitrate,has been *** characterization of the resulting energetic composites was carried out using scanning electron microscopy(SEM),X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),and differential scanning calorimetry(DSC).Isoconversional kinetic analysis was performed to determine the Arrhenius parameters associated with the thermolysis of the elaborated energetic *** is found that TAG-M complexes have strong catalytic effect on the thermo-kinetic decomposition of NC/DEGDN by decreasing the apparent activation energy and significantly increased the total heat *** models that govern the decomposition processes are also studied,and it is revealed that different reaction processes are accomplished by introduction metal complexes of ***,this study serves as a valuable reference for future research focused on the investigation of catalytic combustion features of solid propellants.

关键词： triaminoguanidine transition metal complexes nitrocellulose diethylene glycol dinitrate catalytic effect

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Simultaneous Compression of the Celiac Trunk, Superior Mesenteric Artery, and Renal Arteries by the Median Arcuate Ligament: About One Case

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Open Journal of Medical Imaging 2024年第3期14卷 106-113页

作者： Siddick Oumar Kenza Fathallah Hassan ahmed Aicha Merzem Hasnaa Belgadir Omar Amriss Nadia Moussali Naima el Benna Department of Radiology University Hospital Center Ibn Rochd Casablanca Morocco

Median arcuate ligament syndrome (MALS), is a rare abdominal vascular compression syndrome caused by the compression of the proximal celiac trunk by the median arcuate ligament. According to many authors, a low insertion of the diaphragmatic crura or an abnormally high origin of the celiac trunk from the aorta can cause compression of the celiac artery. Usually, patients with MALS are asymptomatic. Computed tomography (CT) angiography of the abdomen is the main imaging modality to confirm the diagnosis. The coexistence of celiac trunk and superior mesenteric artery compression by the median arcuate ligament is rarely described in the literature. To our knowledge, until now, a simultaneous combination of three abdominal vascular compressions by the median arcuate ligament has never been described. From this case, we report a simultaneous compression of the celiac trunk, superior mesenteric artery, and renal arteries by the median arcuate ligament.

关键词： Median Arcuate Ligament Syndrome (MALS) Celiac Trunk Compression Superior Mesenteric Artery and Renal Arteries Compression Computed Tomography Angiography

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