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Facile synthesis of samarium and cerium doped double perovskite cobaltite with enhanced dielectric response

Journal of Rare Earths 2024年第7期42卷 1317-1327,I0005页

作者： Yasir abbas m.Kamran m.Anis-ur-Rehman Applied Thermal Physics Laboratory Department of PhysicsCOMSATS University IslamabadIslamabad 45550Pakistan

The investigation of Sm-Ce doping on structure,conduction,and dielectric response of Bi_(2)Ca_(2-2x)Sm_(x)CexCoO_(6)(x=0.000,0.025,0.050,0.075)(BCSCCO)are *** the specimens were synthesized by a facile synthesis technique named the co-precipitation route.X-ray diffraction(XRD)reveals that BCSCCO crystallizes into one phase with space group P21/*** crystallite size,dislocation density,lattice parameters,lattice strain,unit cell volume,and bulk density were determined using XRD *** structural properties of Bi_(2)Ca_(2)CoO_(6)were examined using calculations based on the density functional *** and experimental values discrepancy is less than 1%.A scanning electron microscope was used for performing a microstructural *** SEm images demonstrate the homogeneous distribution of grains with a range of sizes(0.054-0.090μm).The alternating current(ac)conductivity,dielectric permittivity,and tangent loss were also studied as a function of frequency(20 Hz-3 mHz)at different temperatures(100-500℃).All synthesized samples were examined using non-linear Debye's function to determine their spreading factor and relaxation *** specimen with the lowest crystallite size(∼23 nm)exhibits a high dielectric permittivity(∼3.80×10^(6)).The conduction mechanism was examined in the studied samples with the use of Jonscher's power *** power law indicates that the BCSCCO(x=0.000,0.025)follows correlated barrier hopping,whereas the x=0.050 and 0.075 compositions follow non-overlapping polaron *** studied specimen Bi_(2)Ca_(1.9)0Sm_(0.05)0Ce_(0.05)_(0)CoO_(6)with the highest density(∼5.65 g/cm^(3))displays a high electrical conductivity(∼46.1 S/cm).These findings correspond to those published for ceramics made from calcium cobaltite using solid-state reactions(5.0-26.0 S/cm).

关键词： Bismuth calcium samarium cerium cobaltite (BCSCCO) Spreading factor Conduction mechanism Rare earths

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Heat transfer analysis in particle-laden flows using the immersed boundary method

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Particuology 2024年第7期90卷 394-403页

作者： Ali abbas Zaidi Department of mechanical Engineering University of Manitoba75A Chancellors CircleWinnipegR3T 5V6Canada

This paper investigates an efficient immersed boundary method(IBm)for multiple-core CPU machines with local grid refinement for the calculation of heat transfer between fluids and finite-sized *** fluid momentum equations are solved by using the fractional step method,while the energy equation is solved by employing the second-order Adams-Bashforth *** efficient load balancing between the CPU cores,the coupling between particles and fluid is obtained by applying the body force in the fluid equations,which depends on the solid volume fraction of particles contained in each grid cell,and then by linearly interpolating the particle temperature and velocity on the fluid grid cell(in place of the delta function commonly used in literature).Several test cases from the literature are studied,and good agreement is observed between the simulation results and the ***,a scaling study on multiple core machines is performed,demonstrating the proposed IBm's capabilities for a significant reduction in processing time.

关键词： Heat transfer Immersed boundary method Particle resolved direct numerical simulations Fluid solid interactions

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聚氨酯泡沫塑料薄层直接分光光度法测定痕量汞(Ⅱ)和苯基汞

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环境科学与管理 1991年第1期23卷 71-73页

作者： m.n.abbas n.B.EL-Assy SH.Abdel-moniem 邹运香

本文介绍了用聚氨酯泡沫塑料(PUF)薄层分光光度法测定 ppb 浓度范围内的汞和苯基汞。汞和苯基汞被吸收在担载二苯基硫卡巴腙(双硫腙)的泡沫塑料平行六面体上,这使有色物质富集了约140倍,因而使其吸光度值大大提高。本法可以得到满意的结... 详细信息

本文介绍了用聚氨酯泡沫塑料(PUF)薄层分光光度法测定 ppb 浓度范围内的汞和苯基汞。汞和苯基汞被吸收在担载二苯基硫卡巴腙(双硫腙)的泡沫塑料平行六面体上,这使有色物质富集了约140倍,因而使其吸光度值大大提高。本法可以得到满意的结果;当试样体积为100ml时,汞和苯基汞的检测极限分别为每升5μg 和10μg。从自来水中,汞和苯基汞的回收率分别为100%和96.6%。

关键词：分光光度法测定痕量汞聚氨酯泡沫塑料吸光度有色物质预富集双硫腙检测极限天然水工作曲线

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Seismic performance evaluation of hybrid coupled shear wall system with shear and flexural fuse-type steel coupling beams

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 691-712页

作者： Zahra Ramezandoust abbas Tajaddini Panam Zarfam Department of Civil Engineering Science and Research branchIslamic Azad UniversityTehran 14778-93855Iran Department of Civil Engineering Karaj BranchIslamic Azad UniversityKaraj 31485-313Iran

Replaceable flexural and shear fuse-type coupling beams are used in hybrid coupled shear wall(HCSW)systems,enabling concrete buildings to be promptly recovered after severe *** study aimed to analytically evaluate the seismic behavior of flexural and shear fuse beams situated in short-,medium-and high-rise RC buildings that have *** building groups hypothetically located in a high seismic hazard zone were studied.A series of 2D nonlinear time history analyses was accomplished in OpenSees,using the ground motion records scaled at the design basis earthquake *** was found that the effectiveness of fuses in HCSWs depends on various factors such as size and scale of the building,allowable rotation value,inter-story drift ratio,residual drift quantity,energy dissipation value of the fuses,*** results show that shear fuses better meet the requirements of rotations and *** contrast,flexural fuses dissipate more energy,but their sectional stiffness should increase to meet other *** was concluded that adoption of proper fuses depends on the overall scale of the building and on how associated factors are considered.

关键词： hybrid coupled shear wall steel fuse coupling beam shear and flexural fuse nonlinear dynamic analysis seismic performance

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Global export flow of Chilean copper:The role of environmental innovation and renewable energy transition

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Geoscience Frontiers 2024年第3期15卷 336-345页

作者： Shujaat abbas najia Saqib Umer Shahzad Graduate School of Economics and management Ural Federal UniversityRussian Federation Brandenburg University of Technology Chair of Energy EconomicsGermany Adnan Kassar School of Business Lebanese American UniversityBeirutLebanon mEU Research Unit Middle East UniversityAmmanJordan Department of Finance College of Business AdministrationPrince Sultan UniversityRiyadhSaudi Arabia Department of Trade and Finance Faculty of Economics and ManagementCzech University of Life Sciences Prague

Copper is one of the most important minerals that has extensive use in environment-friendly technologies and renewable energy *** global urgency for environmental and ecological conservation through renewable energy transition has considerably enhanced the importance of copper and articles *** is a major producer of *** contributes more than one-third to global ***,this study explores the export flow of Chilean copper in response to increasing demand side conditions in major 24 trading partners from 2002 to *** objective is realized by constructing an augmented model for import demand that incorporates bilateral real exchange rate along with real GDP,environmental innovation,and renewable energy transition in major import *** estimated results of panel quantiles via moments techniques reveal a significant positive impact with increasing coefficients at higher quantiles,while environmental innovation and renewable energy transition in trading partners show significant positive impact with decreasing values of coefficients at higher *** findings urge Chile to enhance production capacity of copper and other critical mineral and improve participation in global value chain to meet sharply increasing copper demand from environmental innovation and renewable energy transition.

关键词： Copper Export flow Renewable energy Environmental innovation Panel data Quantiles via moments

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Feedback mechanism-driven mutation Reptile Search Algorithm for Optimizing Interpolation Developable Surfaces

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Journal of Bionic Engineering 2024年第1期21卷 527-571页

作者： Gang Hu Jiao Wang Xiaoni Zhu muhammad abbas Department of Applied mathematics Xi'an University of TechnologyXi'an 710054China School of mechanical and Precision Instrument Engineering Xi'an University of TechnologyXi'an 710048China Department of mathematics University of SargodhaSargodha 40100Pakistan

Curvature lines are special and important curves on *** is of great significance to construct developable surface interpolated on curvature lines in engineering *** this paper,the shape optimization of generalized cubic ball developable surface interpolated on the curvature line is studied by using the improved reptile search ***,based on the curvature line of generalized cubic ball curve with shape adjustable,this paper gives the construction method of SGC-Ball developable surface interpolated on the ***,the feedback mechanism,adaptive parameters and mutation strategy are introduced into the reptile search algorithm,and the Feedback mechanism-driven improved reptile search algorithm effectively improves the solving *** IEEE congress on evolutionary computation 2014,2017,2019 and four engineering design problems,the feedback mechanism-driven improved reptile search algorithm is compared with other representative methods,and the result indicates that the solution performance of the feedback mechanism-driven improved reptile search algorithm is *** last,taking the minimum energy as the evaluation index,the shape optimization model of SGC-Ball interpolation developable surface is *** developable surface with the minimum energy is achieved with the help of the feedback mechanism-driven improved reptile search algorithm,and the comparison experiment verifies the superiority of the feedback mechanism-driven improved reptile search algorithm for the shape optimization problem.

关键词： Reptile search algorithm Feedback mechanism Adaptive parameter mutation strategy SGC-Ball interpolation developable surface Shape optimization

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A Stochastic model to Assess the Epidemiological Impact of Vaccine Booster Doses on COVID-19 and Viral Hepatitis B Co-Dynamics with Real Data

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Computer modeling in Engineering & Sciences 2024年第3期138卷 2973-3012页

作者： Andrew Omame mujahid abbas Dumitru Baleanu Department of mathematics Federal University of TechnologyOwerri460114Nigeria Abdus Salam School of mathematical Sciences Government College UniversityLahore54000Pakistan Department of mathematics Government College UniversityLahore54000Pakistan Department of Computer Science and mathematics Labanese American UniversityBeirutLebanon Institute of Space Sciences Magurele-BucharestRomania Department of medical Research China Medical University HospitalChina Medical UniversityTaichung40402Taiwan

A patient co-infected with COVID-19 and viral hepatitis B can be atmore risk of severe complications than the one infected with a single *** study develops a comprehensive stochastic model to assess the epidemiological impact of vaccine booster doses on the co-dynamics of viral hepatitis B and *** model is fitted to real COVID-19 data from *** proposed model incorporates logistic growth and saturated incidence *** analyses using the tools of stochastic calculus,are performed to study appropriate conditions for the existence of unique global solutions,stationary distribution in the sense of ergodicity and disease *** stochastic threshold estimated from the data fitting is given by:R_(0)^(S)=*** assessments are implemented to illustrate the impact of double-dose vaccination and saturated incidence functions on the dynamics of both *** effects of stochastic white noise intensities are also highlighted.

关键词： Viral hepatitis B COVID-19 stochastic model extinction ergodicity real data

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novel synthesis of stabilized Bi_(1-x-y)Gd_xDy_yO_(1.5) solid electrolytes with enhanced conductivity for intermediate temperature solid oxide fuel cells(SOFCs)

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Journal of Rare Earths 2024年第10期42卷 1903-1911页

作者： Ahmed H.Ibrahim Yehia m.abbas H.A.Ayoub marwa H.Ali mustafa Aldoori materials Science Laboratory Physics DepartmentFaculty of ScienceSuez Canal University41522IsmailiaEgypt ministry of Higher Education and Scientific Research Aliraqia University10011BaghdadIraq

Herein,we report the synthesis of a Dy-Gd co-doped cubic phase-stabilized Bi_(2)O_(3) solid electrolyte system via solid-state processing under atmospheric *** with Dy^(3+) and Gd^(3+) has been observed to significantly enhance the densification process during sintering for stabilization purposes,thereby improving the electrical properties of δ-Bi_2O_(3)-type *** synthesized ceramics were characterized using X-ray diffraction(XRD),field emission scanning electron microscopy-energy dispersive X-ray spectroscopy(FESEm-EDX),thermal gravimetry/differential thermal analysis(TG/DTA),and the four-point probe technique(4PPT).XRD analysis reveals that the samples Bi_(1-x-y)Gd_(x)Dy_(y)O_(1.5)(y=0.05/x=0.05,0.10,0,15,and 0.20,and x=0.05/y=0.10,0.15,and 0.20) exhibit a stable face-centered cubic δ-phase and a mixed-phase crystallographic *** XRD analysis of the stabilized δ-phase suggests that the prepared oxides show a face-centered cubic(FCC) structure with a space group of *** micrographs reveal that the composition Bi_(0.90)Gd_(0.05)Dy_(0.05)O_(1.5) has no significant ***,an evident increase in the pore formation is observed as the amount of Gd_(2O_(3) increases until it reaches 20%.This finding suggests that dense pellets are formed during the sintering process at 900-1000℃.The DTA analyses were performed to verify the phase stability,which agrees with the XRD *** electrochemical performance of the synthesized Dy-Gd co-doped Bi_2O_(3)solid electrolyte system was evaluated and analyzed in detail by using the electrochemical impedance spectroscopy(EIS) technique,Based on EIS and conductivity measurements,Bi_(0.75)Gd_(0.20)Dy_(0.05)O_(1.5) exhibits the lowest activation energy of 0.519 eV and the highest conductivity value of 0.398 S/cm at 627℃compared to the other samples;this composition can be used as a solid electrolyte for intermediatetemperature solid oxide fuel cells(SOFCs).

关键词： Solid oxide fuel cells(SOFCs) Rare earths Solid-state processing Rietveld Fast Fourier transform(FFT) Electrochemical impedance spectroscopy(EIS)

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managing underground legal boundaries in 3D-extending the CityGmL standard

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Underground Space 2024年第1期14卷 239-262页

作者： Bahram Saeidian abbas Rajabifard Behnam Atazadeh mohsen Kalantari The Centre for Spatial Data Infrastructures and Land Administration Department of Infrastructure EngineeringThe University of MelbourneParkvilleVIC 3010Australia School of Civil and Environmental Engineering University of New South WalesSydneyNSW 2052Australia

Legal boundaries are used for delineating the spatial extent of ownership property’s *** underground environments,these boundaries are defined by referencing physical objects,surveying measurements,or ***,there is a gap in connecting and managing these boundaries and underground legal spaces,due to a lack of data model.A 3D data model supporting underground land administration(ULA)should define and model these boundaries and the relationships between them and underground ownership *** 3D data models can be enriched to model underground legal *** research aims to propose a new taxonomy of underground legal boundaries and model them by extending CityGmL,which is a widely used 3D data model in the geospatial science *** developed,implemented,and tested the model for different types of underground legal *** implemented prototype showcased the potential benefits of CityGmL for managing underground legal boundaries in *** proposed 3D underground model can be used to address current challenges associated with communicating and managing legal boundaries in underground *** this data model was specifically developed for Victoria,Australia,the proposed model and approach can be used and replicated in other jurisdictions by adjusting the data requirements for underground legal boundaries.

关键词： Underground Legal boundaries Land administration 3D data model City model

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Predicting density log from well log using machine learning techniques and heuristic optimization algorithm:A comparative study

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Petroleum Research 2024年第2期9卷 176-192页

作者： mehdi Rahmati Ghasem Zargar abbas Ayatizadeh Tanha national Iranian Drilling Company Well Logging DepartmentAhwazIran Faculty member of Petroleum University of Technology Iran Department of Petroleum Engineering Tarbiat Modares UniversityTehranIran

In the petroleum industry,the analysis of petrophysical parameters is critical for efficient reservoir management,production optimization,development strategies,and accurate hydrocarbon reserve *** recent years,the integration of machine learning methodologies has revolutionized the field,addressing challenges in geology,geophysics,and petroleum engineering,even when confronted with limited or imperfect *** study focuses on the prediction of density logs,a pivotal factor in evaluating reservoir hydrocarbon *** is important to note that during well logging operations,log data for specific depths of interest may be missing or incorrect,presenting a significant *** tackle this issue,we employed the Adaptive neuro-Fuzzy Inference System(AnFIS)and Artificial neural networks(Ann)in combination with advanced optimization algorithms,including Particle Swarm Optimization(PSO),Imperialist Competitive Algorithms(ICA),and Genetic Algorithms(GA).These methods exhibit promising performance in predicting density logs from gamma-ray,neutron,sonic,and photoelectric log ***,our results highlight that the Genetic Algorithms-based Artificial neural network(GA-Ann)approach outperforms all other methods,achieving an impressive mean Squared Error(mSE)of *** comparison,AnFIS records an mSE of 0.0015,ICA-Ann 0.0090,PSO-Ann 0.0093,and Ann 0.0183.

关键词： Density log machine learning approaches Artificial neural networks(Ann) Adaptive neuro-fuzzy inference system(AnFIS) Optimization algorithm

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