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应用欧拉-拉格朗日方法分析动脉粥样硬化性颈动脉血流的流-固相互作用

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Journal of Central South University 2024年第1期31卷 151-168页

作者： Majid SIAVASHI Ava BINA Mojtaba SAYADNEJAD Borhan beigzadeh Applied Multi-Phase Fluid Dynamics Lab. School of Mechanical EngineeringIran University of Science and TechnologyTehranIran Biomechatronics and Cognitive Engineering Research Lab. School of Mechanical EngineeringIran University of Science and TechnologyTehranIran

本研究旨在模拟不同狭窄程度和脉搏率的颈动脉搏动血流。采用流-固耦合(FSI)和任意拉格朗日-欧拉(ALE)方法研究了不同狭窄程度、脉搏率和动脉壁性质对周围流体的影响。分别应用Carreau-Yasuda非牛顿超弹性模型和修正Mooney-Rivin超弹性... 详细信息

本研究旨在模拟不同狭窄程度和脉搏率的颈动脉搏动血流。采用流-固耦合(FSI)和任意拉格朗日-欧拉(ALE)方法研究了不同狭窄程度、脉搏率和动脉壁性质对周围流体的影响。分别应用Carreau-Yasuda非牛顿超弹性模型和修正Mooney-Rivin超弹性模型于具有非牛顿行为的血液和超弹性血管壁。结果得到血液的壁面径向位移、压力分布、轴向速度分布和壁面剪切应力。通过增加狭窄的严重程度,轴向速度、血压变化、最大壁面剪切应力和壁面径向位移均呈增长趋势。当脉率在狭窄程度为75%时,最大流量矩、壁面径向位移、压力、轴向速度和壁面剪应力的最大值均增大。此外,与弹性和刚性模型相比,将动脉壁视为超弹性模型,将其周围流体视为非牛顿和非定常,可以使模拟更加真实。在严重程度高达50%的狭窄中,红细胞受到轻微损害,而在严重程度为75%的狭窄中观察到溶血。通过改善动脉粥样硬化,弹性模量从500 k Pa提高到2 MPa,在60 bpm脉率和狭窄程度75%下,剪切应力最大值增长65%。与刚性和弹性动脉壁相比,动脉壁的超弹性模型导致较低的轴向速度、较低的血压、较低的剪切应力和较高的径向位移。

关键词：流-固耦合狭窄严重程度脉率变化超弹性的动脉动脉粥样硬化

Novel in silico EST-SSR markers and bioinformatic approaches to detect genetic variation among peach(Prunus persica L.)germplasm

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Journal of Forestry Research 2020年第4期31卷 1359-1370页

作者： Mehrana Koohi Dehkordi Tayebeh beigzadeh Karim Sorkheh Department of Agronomy Faculty of AgriculturePayame-Noor UniversityP.O.Box 19395-3697TehranIran Department of Agronomy and Plant Breeding Faculty of AgricultureShahid Chamran University of AhvazP.O.Box 61355/144AhvazIran

Because there are thousands of peach cultivars,cultivar classification is a critical step before starting a breeding *** molecular markers such as simple sequence repeats(SSRs)can be *** this study,67 polymorphic primers produced 302 *** values for SI index(1.903)suggested higher genetic variability in the genotype under *** values for observed alleles(Na),expected heterozygosity(He),effective alleles(Ne),Nei’s information index(h),and polymorphic information content(PIC)were 4.5,0.83,5.45,0.83,and 0.81,*** dendrogram constructed based on Jaccard’s similarity coefficients outlined four distinct clusters in the entire *** addition,an analysis of molecular variance(AMOVA)showed that70.68%of the total variation was due to within-population variation,while 29.32%was due to variation among *** to this research,all primers were successfully used for the peach *** EST-SSR markers should be useful in peach breeding programs and other research.

关键词： Expressed sequenced tags(EST) Simple sequence repeats(SSR) Prunus persica L. Genetic diversityl

A new passive transfemoral prosthesis mechanism based on 3R36 knee and ESAR foot providing walking and squatting

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Theoretical & Applied Mechanics Letters 2023年第5期13卷 399-407页

作者： Amer Imran Borhan beigzadeh Mohammad Reza Haghjoo School of Mechanical Engineering Iran University of Science and TechnologyTehranIran Faculty of Mechanical and Energy Engineering Shahid Beheshti University(SBU)TehranIran

Researchers have proposed various linkage mechanisms to connect knee and ankle joints for above-knee prosthe-ses,but most of them only offer natural ***,studies have shown that people assume a squatting posture during daily *** paper introduces a novel mechanism that connects the knee joint with the foot-ankle joint to enable both squatting and *** prosthetic knee used is the well-known 3R36,while the energy storing and return(ESAR)prosthetic foot is used for the ankle-foot *** coordinate knee and ankle joint movements,a six-bar linkage mechanism structure is *** results demonstrate that the proposed modular transfemoral prosthesis accurately mimics the motion patterns of a natural human leg during walking and *** instance,the prosthesis allows a total knee flexion of more than 140°during *** new prosthesis design also incorporates energy-storing mechanisms to reduce energy expenditure during walking for amputees.

关键词： Transfemoral leg amputation Passive prosthesis Squatting Walking Six-bar mechanism Energy saving

Fast and efficient removal of silver(Ⅰ) from aqueous solutions using aloe vera shell ash supported Ni_(0.5)Zn_(0.5)Fe_2O_4 magnetic nanoparticles

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Transactions of Nonferrous Metals Society of China 2016年第8期26卷 2238-2246页

作者： Parisa beigzadeh Farid MOEINPOUR Department of Chemistry Bandar Abbas Branch Islamic Azad University Bandar Abbas *** Iran

Silver (I) was removed from aqueous environment by aloe vera shell ash supported Ni0.5Zn0.5Fe2O4 magnetic *** adsorbent was characterized by several methods including X-ray diffraction (XRD), scanning electron microscopy (SEM), BETisotherm, vibrating sample magnetometer (VSM) and Fourier transform infrared spectroscopy (FT-IR). To determine the absorptionof silver (I) by this adsorbent, different pH values (2?7), adsorbent dose (0.01?0.5 g), concentrations of Ag+ (50, 100, 200, 300, 500,700 and 1000 mg/L) and exposure time (5?100 min) were experimented. The highest removal efficiency of Ag+ was achieved underoptimum condition (30 min and pH=5). The optimum adsorbent dose was 0.20 g (in 50 mL of 100 mg/L Ag+ solution), whichachieved a removal efficiency of 98.3%. The maximum monolayer adsorption capacity based on the Langmuir isotherm is243.90 mg/g. Characterization results revealed that specific surface area and porous volume were 814.23 m2/g and 0.726 cm3/g,respectively. The experimental data were fitted well with the Langmuir and Freundlich isotherm models. Synthesized adsorbent has desired surface area and adsorptive capacity for silver (I) adsorption in aquatic environment.

关键词： dsorption Ag+ ions Ni0.5Zn0.5Fe2O4 aloe vera

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被动动态目标操作:初步定义和例子(英文)

自动化学报 2010年第12期36卷 1711-1719页

作者： beigzadeh Borhan MEGHDARI Ali SOHRABPOUR Saeed Center of Excellence in Design Roboticsand Automation(CEDRA)Mechanical Engineering DepartmentSharif University of Technology

In this work,we introduce a category of dynamic manipulation processes,namely passive dynamic object manipulation,according to which an object is manipulated ***,we study passive dynamic manipulation *** define the main concept,discuss the challenges,and talk about the future *** other passive robotic systems,there are no actuators in these *** object follows a path and travels along it under the effect of its own weight,as well as the interaction force applied by each manipulator on *** select some simple examples to show the *** each example,dynamic equations of motion are derived and the stability of the process is taken into *** this direction,some rules are derived under which we ensure that the manipulation process does not *** support this idea.

关键词：自动化仿真 PDM DNM