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Thermal lens study of the Tris(2,2’-bipyridyl)iron(Ⅱ) tetrafluoroborate

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Optoelectronics Letters 2021年第3期17卷 183-186页

作者： m.D.Zidan m.m.Al-Ktaifani m.s.el-daher A.Allahham A.Ghanem Department of Physics Atomic Energy CommissionDamascus P.O.Box 6091Syria Department of Radioisotopes Atomic Energy CommissionDamascus P.O.Box 6091Syria Higher Institute for Laser Research and Applications Damascus UniversitySyria

Experimental results of thermal lens measurements for Tris(2,2’-bipyridyl)iron(II) tetrafluoroborate solution are reported using the dual beam technique. The temporal evaluation of thermal lens was observed at input pump power of I=47 mW. The thermal lens effect was observed with increasing the pump power intensity as well. The evolution time of thermal lens and the fitting of the experimental transient curve were useful to evaluate the parameters of the Tris(2,2’-bipyridyl)iron(Ⅱ) tetrafluoroborate solution.

关键词： technique. solution. (Ⅱ)

Large magnetocaloric effect and magnetic properties of EuRhO3

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Journal of Rare Earths 2024年第9期42卷 1724-1729页

作者： m.Lassri m.sajieddine A.elouafi A.el Hachmi s.el Ouahbi R.moubah Laboratory of Energy and materials Engineering (LGEm) University of Sultan Moulay SlimaneFaculty of Science and Technology (FST) Institute of Applied Physics (IAP)-school of Industrial management (EmINEs) Mohammed Ⅵ Polytechnic University National school of Applied sciences (ENsA) University of Sultan Moulay Slimane Laboratory of mechanics Production and Industrial Engineering (LMPGI)Higher School of Technology of Casablanca (ESTC)University of Hassan Ⅱ Casablanca Laboratory of Radiation on matter and Instrumentation (LRmI) Faculty of Science and Technology (FST) SettatHassan Ⅰ University Laboatory of Physics of Advanced materials and Thermic (LPmAT) Faculty of Science Ain Chock (FSAC)University of Hassan Ⅱ Casablanca

We report on the structural,magnetic,and magnetocaloric properties of *** oxidation states of Eu and Rh ions were studied using X-ray photoelectron spectroscopy（XPs）.It is found that the Eu ions are mainly in the divalent oxidation state while the Rh ions have+4 ***3powders are found to be antiferromagnetic with a second order magnetic transition at Neel temperature（TN=2.9 K）.Analysis of the magnetic susceptibility versus temperature data in terms of the Curie=Weiss law:(χ=C/（T-θW）) for T>TN,yields θW=-3.1 K and effective magne tic moment ■,which is close to the theoretical value ■.The magnetic entropy change(-Δsm),was determined by em ploying the thermodynam ic maxwell's *** μ0H=5 T and near TN,■ and relative cooling power（RCP） exhibit large values of 33.7 J/（kg·K） and 238 J/kg,*** large magnitude of-Δsmand RCP show that the EuRhO3compound could be a potential candidate to be used in cryogenic magnetic refrigeration.

关键词： Cryogenic magnetic refrigeration magnetic properties magnetocaloric effect Rare earths X-ray photoelectron spectroscopy

multiple scales method for analyzing a forced damped rotational pendulum oscillatorwithgallows

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Communications in Theoretical Physics 2024年第5期76卷 58-67页

作者： Haifa A Alyousef Alvaro H salas B m Alotaibi s A el-Tantawy Department of Physics College of SciencePrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh 11671Saudi Arabia Department of mathematics and statistics Universidad Nacional de ColombiaFIZMAKO Research GroupColombia Department of Physics Faculty of SciencePort Said UniversityPort Said 42521Egypt Research Center for Physics(RCP) Department of PhysicsFaculty of Science and ArtsAl-MikhwahAl-Baha UniversityAl-Baha 1988Saudi Arabia

This study reports the analytical solution for a generalized rotational pendulum system with gallows and periodic excited *** multiple scales method(msm)is applied to solve the proposed *** types of rotational pendulum oscillators are studied and talked about in *** include the forced damped rotating pendulum oscillator with gallows,the damped standard simple pendulum oscillator,and the damped rotating pendulum oscillator without *** msm first-order approximations for all the cases mentioned are derived in *** obtained results are illustrated with concrete numerical *** first-order msm approximations are compared to the fourth-order Runge-Kutta(RK4)numerical ***,the maximum error is estimated for the first-order approximations obtained through the msm,compared to the numerical approximations obtained by the RK4 ***,we conducted a comparative analysis of the outcomes obtained by the used method(msm)and He-msm to ascertain their respective levels of *** proposed method can be applied to analyze many strong nonlinear oscillatory equations.

关键词： rotational pendulum system multiple scales method approximate solution damped oscillations forced pendulum with gallows he-multiple scales method

Nonlinear wave dispersion in monoatomic chains with lumped and distributed masses:discrete and continuum models

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Applied mathematics and mechanics(English Edition) 2024年第4期45卷 633-648页

作者： E.GHAVANLOO s.el-BORGI school of mechanical Engineering Shiraz UniversityShiraz 71963-16548Iran mechanical Engineering Program Texas A&M University at QatarDoha 23874Qatar

The main objective of this paper is to investigate the influence of inertia of nonlinear springs on the dispersion behavior of discrete monoatomic chains with lumped and distributed *** developed model can represent the wave propagation problem in a non-homogeneous material consisting of heavy inclusions embedded in a *** inclusions are idealized by lumped masses,and the matrix between adjacent inclusions is modeled by a nonlinear spring with distributed ***,the model is capable of depicting the wave propagation in bi-material bars,wherein the first material is represented by a rigid particle and the second one is represented by a nonlinear spring with distributed *** discrete model of the nonlinear monoatomic chain with lumped and distributed masses is first considered,and a closed-form expression of the dispersion relation is obtained by the second-order Lindstedt-Poincare method(LPm).Next,a continuum model for the nonlinear monoatomic chain is derived directly from its discrete lattice model by a suitable continualization *** subsequent use of the second-order method of multiple scales(mms)facilitates the derivation of the corresponding nonlinear dispersion relation in a closed *** novelties of the present study consist of(i)considering the inertia of nonlinear springs on the dispersion behavior of the discrete mass-spring chains;(ii)developing the second-order LPm for the wave propagation in the discrete chains;and(iii)deriving a continuum model for the nonlinear monoatomic chains with lumped and distributed ***,a parametric study is conducted to examine the effects of the design parameters and the distributed spring mass on the nonlinear dispersion relations and phase velocities obtained from both the discrete and continuum *** parameters include the ratio of the spring mass to the lumped mass,the nonlinear stiffness coefficient of the spring,and the wave amplitude.

关键词： nonlinear mass-spring chain discrete model continuum model LindstedtPoincare method(LPm) method of multiple scales(mms) dispersion phase velocity

Genetic Variability and Phenotypic Correlations study among Grain Quality Traits and mineral elements Concentrations in Colored and Non-Colored Rice (Oryza sativa L.)

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1733-1748页

作者： Adel A.Rezk mohamed m.el-malky Heba I.mohamed Hossam.s.el-Beltagi Agricultural Biotechnology Department College of Agricultural and Food ScienceKing Faisal UniversityAl-Ahsa31982Saudi Arabia Plant Pathology Research Institute Agriculture Research CenterGiza12619Egypt Rice Research and Training Center Field Crop Research InstituteAgriculture Research Center33717Egypt Biological and Geological sciences Department Faculty of EducationAin Shams UniversityCairo11511Egypt Biochemistry Department Faculty of AgricultureCairo UniversityGiza12613Egypt

Twenty-four rice genotypes were examined to assess genetic variability,heritability,and correlations for seven-grain quality traits,eight nutritional elements,and *** revealed signiﬁcant differences for the quality traits *** every trait under study,the phenotypic coefﬁcient of variation was higher than the correspon-dence genotypic coefﬁcient of *** in a broad sense varied from 29.75%for grain length to 98.31%for the elongation *** percentage recovery had a highly signiﬁcant positive correlation with milling and head rice ***,milling percentage had a highly positive correlation with head rice *** amylose percentage,all the genotypes belonged to low amylose except the Hassawi-1 variety,which had intermediate amylose *** nutrition contents of magnesium(mg),sodium(Na),potas-sium(K),calcium(Ca),copper(Cu),manganese(mn),zinc(Zn),iron(Fe),or protein percentage gave different variations for 24 rice genotypes under all the nutritional *** the 24 genotypes,ten rice genotypes–HighNutrient-1,HighNutrient-2,HighNutrient-9,HighNutrient-8,HighNutrient-3,Hassawi-2,HighNutrient-7,HighNutrient-6,Hassawi-1,and HighNutrient-4–had the highest heist value for all nutritional and protein con-tents,and could be used as a donor to improving new *** was a positive and signiﬁcant correlation between magnesium mg,K,Zn and ***,K had a positive correlation with zinc Zn,Fe,and protein *** analysis was divided into two groups:theﬁrst group included all genotypes rich in nutri-ents,while the remaining genotypes with low nutritional content were included in the second group.

关键词： Amylose cluster analysis genotypes grain quality mineral nutrition rice

magneto-Photo-Thermoelastic Excitation Rotating semiconductor medium Based on moisture Diffusivity

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Computer modeling in Engineering & sciences 2024年第10期141卷 107-126页

作者： Khaled Lotfy A.m.s.mahdy Alaa A.el-Bary E.s.elidy Department of mathematics Faculty of ScienceZagazig UniversityZagazig44519Egypt Department of mathematics Faculty of ScienceTaibah UniversityMadinah42353Saudi Arabia Department of mathematics and statistics College of ScienceTaif UniversityTaif11099Saudi Arabia Arab Academy for science Technology and Maritime TransportAlexandria1029Egypt

In this research,we focus on the free-surface deformation of a one-dimensional elastic semiconductor medium as a function of magnetic field and moisture *** problem aims to analyze the interconnection between plasma and moisture diffusivity processes,as well as thermo-elastic *** study examines the photothermoelasticity transport process while considering the impact of moisture *** employing Laplace’s transformation technique,we derive the governing equations of the photo-thermo-elastic *** equations include the equations for carrier density,elastic waves,moisture transport,heat conduction,and constitutive *** stresses,thermal conditions,and plasma boundary conditions are used to calculate the fundamental physical parameters in the Laplace *** employing numerical techniques,the Laplace transform is inverted to get complete time-domain solutions for the primary physical domains under ***,thermoelastic,and thermoelectric characteristics are employed in conjunction with a graphical analysis that takes into consideration the effects of applied forces on displacement,moisture concentration,carrier density,stress due to forces,and temperature distribution.

关键词： moisture diffusivity semiconductor photothermoelastic rotation thermomechanical waves laplace transform

A hybrid machine-learning model for solar irradiance forecasting

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CLEAN ENERGY 2024年第1期8卷 100-110页

作者： Almarzooqi, Ameera m. maalouf, maher el-Fouly, Tarek H. m. Katzourakis, Vasileios E. el moursi, mohamed s. Chrysikopoulos, Constantinos, V Khalifa Univ Dept Ind & Syst Engn POB 127788 Abu Dhabi U Arab Emirates Khalifa Univ Abu Dhabi Elect Engn & Comp Sci Dept Abu Dhabi U Arab Emirates Khalifa Univ Dept Civil Infrastruct & Environm Engn POB 127788 Abu Dhabi U Arab Emirates Tech Univ Crete Sch Chem & Environm Engn Khania 73100 Greece

Nowcasting and forecasting solar irradiance are vital for the optimal prediction of grid-connected solar photovoltaic (PV) power plants. These plants face operational challenges and scheduling dispatch difficulties due to the fluctuating nature of their power output. As the generation capacity within the electric grid increases, accurately predicting this output becomes increasingly essential, especially given the random and non-linear characteristics of solar irradiance under variable weather conditions. This study presents a novel prediction method for solar irradiance, which is directly in correlation with PV power output, targeting both short-term and medium-term forecast horizons. Our proposed hybrid framework employs a fast trainable statistical learning technique based on the truncated-regularized kernel ridge regression model. The proposed method excels in forecasting solar irradiance, especially during highly intermittent weather periods. A key strength of our model is the incorporation of multiple historical weather parameters as inputs to generate accurate predictions of future solar irradiance values in its scalable framework. We evaluated the performance of our model using data sets from both cloudy and sunny days in seattle and medford, UsA and compared it against three forecasting models: persistence, modified 24-hour persistence and least squares. Based on three widely accepted statistical performance metrics (root mean squared error, mean absolute error and coefficient of determination), our hybrid model demonstrated superior predictive accuracy in varying weather conditions and forecast horizons. A novel prediction method for solar irradiance, targeting both short-term and medium-term forecast horizons, is proposed to improve PV power production. The hybrid framework employs a fast trainable statistical learning technique based on the truncated-regularized kernel ridge regression model. Graphical Abstract

关键词： solar power generation kernel ridge regression hybrid model forecasting BATTERY ENERGY-sTORAGE POWER PV RADIATION PREDICTION CelLs

Existence results and behavior analysis for nonlinear age-dependent population dynamics problems with conformable fractional operator

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International Journal of Biomathematics 2024年第5期17卷 229-256页

作者： Hiba el Asraoui m'hamed el Omari Ali el mfadel Khalid Hilal Laboratory of Applied mathematics scientific Computing sultan moulay slimane University BP 523 Beni MellalMorocco

In this paper,we investigate the existence of solutions and analyze the large-time behavior for Gurtin-maccamy population model involving conformable fractional *** a preliminary step,we construct a generic structure of the solution associated with our proposed model by utilizing some basic properties and tools of conformable fractional *** establish the existence of a unique solution of the given model with the given initial *** last,by using the upper and lower solutions for the characteristic equation,we define the upper and lower boundaries for the obtained solution and describe the large-time behavior of the total population.

关键词： Age-dependent population conformable fractional operator upper and lower boundary of the solution dynamics of populations

sodium nitroprusside as a signal molecule for up-regulating membrane characteristics,antioxidant defense system to improve flax productivity under water stress

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Oil Crop science 2024年第3期9卷 160-169页

作者： N.m.Al-Ashkar B.A.Bakry H.m.s.el-Bassiouny m.m.s.Abdallah m.s.sadak Botany Department Agricultural and Biological Research InstituteNational Research Centre33 El Bohouth Street P.O.12622DokkiGizaEgypt Field Crops Research Department Agricultural and Biological Research InstituteNational Research Centre33 El Bohouth Street P.O.12622DokkiGizaEgypt

Water stress is a critical environmental adversity that significantly impacts the growth,development,and yield of flax *** this study,flax seeds were cultivated under different water irrigation requirements(WIR)(100%,75%,and 50%)to investigate the effects of exogenously supplied nitric oxide(NO)donor sodium nitroprusside(sNP)as foliar treatments at concentrations of 0.0 mmol/L,0.5 mmol/L,1.0 mmol/L,and 2.0 mmol/*** stress led to a significant decrease in plant growth,photosynthetic pigments,yield components such as oil and total carbohydrate *** also resulted in an increase in leaf H2O2 production,lipid peroxidation levels and activities of enzymatic antioxidants including polyphenol oxidase,superoxide dismutase,and nitrate reductase ***,foliar application of sNP improved photosynthetic pigments and antioxidant defense system which mitigated the negative impact of water stress on growth and yield productivity by reducing oxidative damage caused by reactive oxygen species *** use of sNP also decreased H_(2)O_(2) accumulation levels,lipid peroxidation levels,and improved membrane *** treatment at concentration of 2 mmol/L showed superior results compared to other concentrations with extremely significant increases observed in yield characteristics such as oil content,total carbohydrate percentages,and unsaturated fatty acids to saturated fatty acids ratio.

关键词： Flax Fatty acid sodium nitroprusside Antioxidant enzymes Yield