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International Journal of Minerals,Metallurgy and Materials 2016年第6期23卷 676-682页

作者： Hamid Sazegaran ali-reza kiani-rashid Jalil Vahdati Khaki Department of Metallurgical and Materials Engineering Faculty of Engineering Ferdowsi University of Mashhad

The effects of sphere size on the microstructural and mechanical properties of ductile iron–steel hollow sphere（DI–SHS） syntactic foams were investigated in this study. The SHSs were manufactured by fluidized-bed coating via the Fe-based commercial powder–binder suspension onto expanded polystyrene spheres（EPSs）. Afterwards, the DI–SHS syntactic foams were produced via a sand-mold casting process. The microstructures of specimens were investigated by optical microscopy, scanning electron microscopy（SEM）, and energy-dispersive X-ray spectroscopy（EDS）. The microscopic evaluations of specimens reveal distinct regions composed of the DI matrix, SHS shells, and compatible interface. As a result, the microstructures and graphite morphologies of the DI matrix depend on sphere size. When the sphere size decreases, the area fractions of cementite and graphite phases are observed to increase and decrease, respectively. Compression tests were subsequently conducted at ambient temperature on the DI–SHS syntactic foams. The results reveal that the compression behavior of the syntactic foams is enhanced with increasing sphere size. Furthermore, the compressed specimens demonstrate that microcracks start and grow from the interface region.

关键词： ductile iron steel syntactic foams microstructure mechanical properties

Effects of copper content on the shell characteristics of hollow steel spheres manufactured using an advanced powder metallurgy technique

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International Journal of Minerals,Metallurgy and Materials 2016年第4期23卷 434-441页

作者： Hamid Sazegaran ali-reza kiani-rashid Jalil Vahdati Khaki Department of Materials Science and Metallurgical Engineering Engineering Faculty Ferdowsi University of Mashhad

Metallic hollow spheres are used as base materials in the manufacture of hollow sphere structures and metallic foams. In this study, steel hollow spheres were successfully manufactured using an advanced powder metallurgy technique. The spheres＇ shells were characterized by optical microscopy in conjunction with microstructural image analysis software, scanning electron microscopy（SEM）, energy-dispersive X-ray spectroscopy（EDX）, and X-ray diffraction（XRD）. The microscopic evaluations revealed that the shells consist of sintered iron powder, sintered copper powder, sodium silicate, and porosity regions. In addition, the effects of copper content on various parameters such as shell defects, microcracks, thickness, and porosities were investigated. The results indicated that increasing the copper content results in decreases in the surface fraction of shell porosities and the number of microcracks and an increase in shell thickness.

关键词： steel hollow spheres powder metallurgy copper content shell characteristics

Modeling the dynamical behavior of the interaction of T-cells and human immunodeficiency virus with saturated incidence

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Communications in Theoretical Physics 2024年第3期76卷 1-14页

作者： Salah Boulaaras rashid Jan Amin Khan ali Allahem Imtiaz Ahmad Salma Bahramand Department of Mathematics College of ScienceQassim UniversityBuraydah51452Saudi Arabia Institute of Energy Infrastructure(IEI) Department of Civil EngineeringCollege of EngineeringUniversiti Tenaga Nasional(UNITEN)Putrajaya CampusJalan IKRAM-UNITEN43000 KajangSelangorMalaysia Department of Mathematics University of SwabiSwabi 23561Pakistan Department of Mathematics College of SciencesQassim UniversitySaudi Arabia Institute of Informatics and Computing in Energy(IICE) Universiti Tenaga NasionalKajangSelangorMalaysia Department of Political Science Bacha Khan University CharsaddaCharsadda 24420KPK Pakistan

In the last forty years,the rise of HIV has undoubtedly become a major concern in the field of public health,imposing significant economic burdens on affected ***,it becomes imperative to undertake comprehensive investigations into the mechanisms governing the dissemination of HIV within the human *** this work,we have devised a mathematical model that elucidates the intricate interplay between CD4^(+)T-cells and viruses of HIV,employing the principles of fractional *** production rate of CD4^(+)T-cells,like other immune cells depends on certain factors such as age,health status,and the presence of infections or ***,we incorporate a variable source term in the dynamics of HIV infection with a saturated incidence rate to enhance the precision of our *** introduce the fundamental concepts of fractional operators as a means of scrutinizing the proposed HIV *** facilitate a deeper understanding of our system,we present an iterative scheme that elucidates the trajectories of the solution pathways of the *** show the time series analysis of our model through numerical findings to conceptualize and understand the key factors of the *** addition to this,we present the phase portrait and the oscillatory behavior of the system with the variation of different input *** information can be utilized to predict the long-term behavior of the system,including whether it will converge to a steady state or exhibit periodic or chaotic oscillations.

关键词： HIV infection fractional-calculus dynamics of HIV iterative scheme dynamical behaviour mathematical model fractional derivatives

The role of green industrial transformation in mitigating carbon emissions:Exploring the channels of technological innovation and environmental regulation

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Energy and Built Environment 2024年第3期5卷 464-479页

作者： Saima Mehmood Khalid Zaman Shiraz Khan Zohaib ali Haroon ur rashid Khan Department of Economics The University of HaripurHaripurKhyber Pakhtunkhwa 22620Pakistan Department of Management Sciences The University of HaripurHaripurKhyber Pakhtunkhwa 22620Pakistan Department of Energy and Process Engineering(EPT) Norwegian University of Science and TechnologyHøgskoleringen 1Trondheim 7034Norway Faculty of Business The University of Wollongong in DubaiDubai 20183United Arab Emirates

The industrial sector is vital to economic progress,yet industrial pollution poses environmental and economic *** purpose of the study was to investigate the influence of green industrial transformation in re-ducing Pakistan’s carbon intensity between 1975 and *** emissions are considered an endogenous construct,while foreign direct investment(FDI)inflows,technological innovation,green industrial transforma-tion,environmental legislation,and research and development(R&D)investment are possible *** association between variables is assessed using the robust least-squares *** industrial transforma-tion is connected with lower carbon emissions,yet technical innovation,R&D investment,and inbound FDI raise a country’s carbon *** findings support the pollution haven hypothesis in a *** causality esti-mates indicate that inward FDI contributes to environmental regulations;green industrial transformation directly relates to inbound FDI and R&D expenditures;and technological innovations correspond to inbound FDI,R&D ex-penditures,industrial ecofriendly progression,and environmental *** to the impulse response function,environmental policies are anticipated to have a differential effect on carbon emissions in 2023,2024,2028-2030,while they are likely to decrease in the years 2025-2027 and 2031 ***,inward FDI and technology advancements would almost certainly result in a rise in carbon emissions over *** industrial transitions are projected to result in a ten-year reduction in carbon *** variance decomposi-tion analysis indicates that eco-friendly industrial adaptations would likely have the largest variance error shock on carbon emissions(11.747%),followed by inbound FDI,technological advancements,and regulatory changes,with R&D spending having a minimal impact over ***’s economy should foster a green industrial revolution to avoid pollution and increase environm

关键词： Carbon intensity Industrial green transformation Environmental regulations Technological innovations Robust least squares regression

Bulk-boundary and RPS thermodynamics from topology perspective

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Chinese Physics C 2024年第9期48卷 244-253页

作者： Jafar Sadeghi Mohammad reza alipour Saeed Noori Gashti Mohammad ali S.Afshar Department of Physics Faculty of Basic SciencesUniversity of Mazandaran P.O.Box 47416-95447BabolsarIran School of Physics Damghan UniversityP.O.Box ***DamghanIran

In this study,we investigate the bulk-boundary and restricted phase space(RPS)thermodynamics of Rissner-Nordstrom(R-N)AdS and 6-dimensional charged Gauss-Bonnet AdS black ***,we examine the topological characteristics of the considered black holes and compare them with the results of extended *** determine that the topological behavior of the bulk-boundary thermodynamics is the same as that of the extended thermodynamics,whereas the RPS thermodynamics exhibits a distinct ***,we demonstrate that within the RPS formalism,there is only one critical point with a topological charge of+1(Q_(t)=+1).Moreover,in the RPS formalism,the inclusion of higher-derivative curvature terms in the form of GaussBonnet gravity does not alter the topological classification of critical points in charged AdS black holes.

关键词： bulk-boundary restricted phase space topological charge thermodynamics

A New Approach for the Determination of Metronidazole Using Switchable Solvent Coupled with Au-MWCNTs-Modified Electrochemical Sensor

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Journal of Analysis and Testing 2024年第2期8卷 191-200页

作者： Siamak kiani Shahvandi Mehrorang Ghaedi Hamid Ahmar Chemistry Department Yasouj UniversityYasouj75918-74831Iran Chemistry Department University of ZabolZabol98615-538Iran

In this work,a new liquid-phase microextraction method coupled with an electrochemical technique using a switchable solvent was proposed for the determination of *** extraction solvent used was dipropylamine(DPA),which exhibited switchable *** means that it can become miscible or immiscible when in contact with carboxylic acids in the aqueous *** metronidazole was then measured using a glassy carbon electrode that was modified with Au-multiwalled carbon nanotubes(MWCNTs).The eff ect of diff erent parameters such as the type and amount of trigger,the addition of salt,and the volume of extraction solvent on the e fficiency of switchable hydrophilic solvent-based liquid-phase microextraction(SHS-LPME)was investigated using the one-factor-at-a-time *** optimizing the conditions,the linear calibration curve was obtained in the concentration range of 0.005–250μmol/***,the limit of quantification(LOQ)of 0.005μmol/L and the limit of detection(LOD)of 0.0015μmol/L were obtained,respectively.

关键词： Switchable solvent Metronidazole Liquid-phase microextraction Electrochemical techniques

Numerical study of convective heat transfer in static arrangements of particles with arbitrary shapes:A monolithic hybrid lattice Boltzmann-finite difference-phase field solver

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Particuology 2024年第2期85卷 186-197页

作者： reza Namdar Mohammadhassan Khodsiani Hesameddin Safari Tanya Neeraj Seyed ali Hosseini Frank Beyrau Benoit Fond Dominique Thevenin Fathollah Varnik Interdisciplinary Centre for Advanced Materials Simulation(ICAMS) Ruhr-University BochumBochum44801Germany Laboratory of Technical Thermodynamics University of Magdeburg"Otto von Guericke"Magdeburg39106Germany Laboratory of Fluid Dynamics and Technical Flows University of Magdeburg"Otto von Guericke"MagdeburgD-39106Germany Department of Mechanical and Process Engineering ETH ZurichZurich8092Switzerland ONERA The French Aerospace Lab Department of AerodynamicsAeroelasticity and Acoustics(DAAA)Paris-Saclay UniversityMeudon92190France

A compressible lattice Boltzmann-finite difference method is extended by the phase-field approach into a monolithic scheme to study fluid flow and heat transfer through regular arrangements of solid bodies of circular,elliptical and irregular *** advantage of using the phase-field method is demon-strated both in its simplicity of accounting for flow and thermal boundary conditions at solid surfaces with irregular shapes and in the capability of generating such complex-shaped *** an array of discs,numerical results for the overall solid-to-gas heat transfer rate are validated via experiments on flow through arrays of hot *** thus validated compressible LB-FD-PF hybrid scheme is used to study the dependence of heat transfer on flow and thermal boundary conditions(Reynolds number,temperature difference between the hot solid bodies and the inlet gas),porosity as well as on the shape of solid *** are rationalized in terms of the residence time of the gas close to the solid body and downstream variations of gas velocity and *** for further applications of the proposed methodology are also discussed.

关键词： Lattice Boltzmann method Finite difference scheme Convective heat transfer Diffuse interface Thermal compressible flow

Novel Investigation of Stochastic Fractional Differential Equations Measles Model via the White Noise and Global Derivative Operator Depending on Mittag-Leffler Kernel

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2289-2327页

作者： Saima rashid Fahd Jarad Department of Mathematics Government College UniversityFaisalabad38000Pakistan Department of Natural Sciences School of Arts and SciencesLebanese American UniversityBeirut11022801Lebanon Department of Mathematics Faculty of Arts and ScienceÇnkaya UniversityAnkara06790Turkey Department of Medical Research China Medical UniversityTaichung40402TaiwanChina

Because of the features involved with their varied kernels,differential operators relying on convolution formulations have been acknowledged as effective mathematical resources for modeling real-world *** this paper,we constructed a stochastic fractional framework of measles spreading mechanisms with dual medication immunization considering the exponential decay and Mittag-Leffler *** this approach,the overall population was separated into five ***,the descriptive behavior of the system was investigated,including prerequisites for the positivity of solutions,invariant domain of the solution,presence and stability of equilibrium points,and sensitivity *** included a stochastic element in every cohort and employed linear growth and Lipschitz criteria to show the existence and uniqueness of *** numerical simulations for various fractional orders and randomization intensities are illustrated.

关键词： Measles epidemic model Atangana-Baleanu Caputo-Fabrizio differential operators existence and uniqueness qualitative analysis Newton interpolating polynomial

Nonlinear phenomena in vibrations of embedded carbon nanotubes conveying viscous fluid

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Nanotechnology and Precision Engineering 2024年第1期7卷 44-54页

作者： reza Ebrahimi Mechanical Engineering Faculty of EngineeringYasouj UniversityYasouj 75918-74831Iran

Various nonlinear phenomena such as bifurcations and chaos in the responses of carbon nanotubes(CNTs)are recognized as being major contributors to the inaccuracy and instability of nanoscale mechanical ***,the main purpose of this paper is to predict the nonlinear dynamic behavior of a CNT conveying viscousﬂuid and supported on a nonlinear elastic *** proposed model is based on nonlocal Euler–Bernoulli beam *** Galerkin method and perturbation analysis are used to discretize the partial differential equation of motion and obtain the frequency-response equation,respectively.A detailed parametric study is reported into how the nonlocal parameter,foundation coefﬁcients,ﬂuid viscosity,and amplitude and frequency of the external force inﬂuence the nonlinear dynamics of the ***,quasi-periodic,and chaotic behaviors and hardening nonlinearity are revealed by means of the vibration time histories,frequency-response curves,bifurcation diagrams,phase portraits,power spectra,and Poincaré***,the results show that it is possible to eliminate irregular motion in the whole range of external force amplitude by selecting appropriate parameters.

关键词： Nonlinear vibration Carbon nanotubes Nonlocal effect Viscousﬂuid Nonlinear elastic medium

Outcomes of surgical correction of Peyronie’s disease with plaque excision and grafting: Comparison of testicular tunica vaginalis graft versus bovine pericardium graft

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Asian Journal of Urology 2024年第3期11卷 497-503页

作者： ali Eslahi Faisal Ahmed Mohammad reza Askarpour Hossein-ali Nikbakht Iman Shamohammadi Payam Ghasemi Hanieh alimardani Bahareh Ebrahimi Department of Urology School of MedicineShiraz University of Medical SciencesShirazIran Shiraz Geriatric Research Center Shiraz University of Medical SciencesShirazIran Urology Research Center Al-Thora General HospitalDepartment of UrologySchool of MedicineIbb University of Medical SciencesIbbYemen Social Determinants of Health Research Center Health Research InstituteBabol University of Medical SciencesBabolIran

Objective:Peyronie’s disease(PD)is an abnormal wound healing in the penile tunica *** fibrotic plaque excision,different graft materials have been used to repair the defects,but the optimal graft remains *** study aimed to compare the functional outcomes of testicular tunica vaginalis grafts and bovine pericardium grafts in patients with severe ***:A retrospective comparative study was conducted on 33 PD patients undergoing partial plaque excision and grafting from September 2015 to May *** patients were divided into two groups depending on the type of graft *** 15 patients in Group B,testicular tunica vaginalis grafts were used to repair the defect,while for 18 patients in Group A,bovine pericardium grafts were *** of the patient’s age,comorbidities,sexual function,penile curvature,postoperative complications,need for further treatment,change in penile length,and satisfaction were gathered and compared between the *** function was evaluated using the 5-item version of the International Index of Erectile Function(IIEF-5),and a functional less than 20-degree penile curvature after surgery was considered a successful ***:There was no difference in age,comorbidities,degree of curvature,perioperative IIEF-5,operative time,plaque size,or complication *** surgery,a statistically significant improvement in curvature degree(palis or bovine pericard

关键词： Peyronie's disease Plaqueexcision Testiculartunica vaginalis graft Bovinepericardium graft