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Three-Dimensional Analysis of Buried Steel Pipes under Moving Loads

Open Journal of Geology 2017年第1期7卷 1-11页

作者： Bahram Navayi Neya Mehdi alijani Ardeshir ali aghajani Delavar Mohammad Zaman Roshan Bakhsh Faculty of Civil Engineering Babol Noshirvani University of Technology Babol Iran Mazandaran Gas Company Sari Iran

The three-dimensional response of buried steel pipes under vehicle loads is investigated using the finite element analysis. The analysis is conducted using the finite element program ABAQUS. The effects of the vehicle parameters, pipeline parameters and soil parameters on the response of the buried pipeline were discussed. The results indicate that the maximum principal stresses in a buried pipe under vehicle loads are significant for burial depths of less than 1 m. The maximum principal stresses of the buried pipeline decrease as the burial depth, vehicle velocity and surrounding soil’s elasticity modulus increase. For small burial depths, the stresses in buried pipes caused by vehicle motion in the direction normal to the pipe axis are more critical. However, the effects of motion direction are insignificant when the burial depth and the surrounding soil’s elasticity modulus increase. As the diameter of a buried pipe decreases, the maximum principal stresses increase.

关键词： Buried Steel Pipeline Vehicles Load Motion Direction Numerical Simulation Stress

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双相钢的局部激光热处理

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热处理技术与装备 2012年第1期33卷 41-41页

作者： Mehdi Asadi Georg Frommeyer ali aghajani Ilana Timokhina Heinz Palkowski

本项研究的处理工艺可以强化热轧双相(dual-phase DP)钢。为此研究了一种能达到局部强化的方法,即局部激光热处理(laser heat treatment LHT)。DP钢板以不同程度的预应变,用冷轧随后激光热处理达到整体而均匀的变形。经选择各种参数进... 详细信息

本项研究的处理工艺可以强化热轧双相(dual-phase DP)钢。为此研究了一种能达到局部强化的方法,即局部激光热处理(laser heat treatment LHT)。DP钢板以不同程度的预应变,用冷轧随后激光热处理达到整体而均匀的变形。经选择各种参数进行此项处理后,用光学显微镜(LOM)、扫描电镜(SEM)、透射电镜(TEM)、硬度测量和拉伸试验来评估热处理区的表面和横截面的显微组织,以及力学性能。结果说明用局部热处理能得到局部高强度。在较低的处理温度,这种效应可认为是烘烤强化(bake hardening BH),增加预应变和温度,从而提高局部性能。随着处理温度增加影响表面附近的初始组织。用激光局部强化DP钢开辟了一个新的领域,应用于把强化效应用到只影响感兴趣的相关区域,因此提供了节能的潜力和能设计零部件的性能。

关键词：激光热处理双相钢局部强化力学性能显微组织光学显微镜局部热处理扫描电镜

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Thermal performance and entropy generation for nanofluid jet injection on a ribbed microchannel with oscillating heat flux: Investigation of the first and second laws of thermodynamics

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Chinese Journal of Chemical Engineering 2022年第2期35卷 450-464页

作者： Yu-Liang Sun Davood Toghraie Omid ali Akbari Farzad Pourfattah As’ad alizadeh Navid Ghajari Mehran aghajani School of Science Huzhou UniversityHuzhou 313000China Department of Mechanical Engineering Khomeinishahr BranchIslamic Azad UniversityKhomeinishahrIran Young Researchers and Elite Club Khomeinishahr BranchIslamic Azad UniversityKhomeinishahrIran Department of Mechanical Engineering University of KashanKashanIran Department of Mechanical Engineering College of EngineeringUniversity of ZakhoZakhoIraq

In current numerical study,forced flow and heat transfer of water/NDG(Nitrogen-doped graphene)nanofluid in nanoparticles mass fractions(φ)of 0,2%and 4%at Reynolds numbers(Re)of 10,50,100 and 150 are simulated in steady *** geometry is a two-dimensional microchannel under the influence of nanofluid jet *** of inlet fluid equals with Tc=293 K and hot source of microchannel is under the influence of oscillating heat ***,in this research,the effect of the variations of attack angle of triangular rib(15°,30°,45°and 60°)on laminar nanofluid flow behavior inside the studied rectangular geometry with the ratio of L/H=28 and nanofluid jet injection is *** results indicate that the increase of Reynolds number,nanoparticles mass fraction and attack angle of rib leads to the increase of pressure *** increasing fluid viscosity,momentum depreciation of fluid in collusion with microchannel surfaces ***,the increase of attack angle of rib at higher Reynolds numbers has a great effect on this *** low Reynolds numbers,due to slow motion of fluid,variations of attack angle of rib,especially in angles of 30°,45°and 60°are almost *** increasing fluid velocity,the effect of the variations of attack angle on pressure drop becomes significant and pressure drop figures act *** general,by using heat transfer enhancement methods in studied geometry,heat transfer increases almost 25%.

关键词： Ribbed microchannel Forced heat transfer Numerical study Nanofluid Attack angle of rib

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Prevalence of non-tuberculosis mycobacteria among samples deposited from the National Tuberculous Reference Laboratory of Iran(2011-2018)

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Asian Pacific Journal of Tropical Medicine 2021年第10期14卷 451-456页

作者： Saman Ayoubi Parissa Farnia Poopak Farnia Jafar aghajani Jalaledin Ghanavi ali Akbar Velayati Mycobacteriology Research Center(MRC) National Research Institute of Tuberculosis and Lung Disease(NRITLD)Shahid Beheshti University of Medical SciencesTehranIran Department of Biotechnology School of Advanced Technology in MedicineShahid Beheshti University of Medical SciencesTehranIran

Objective:To investigate the prevalence of non-tuberculosis mycobacteria(NTM)among the samples deposited from the National Tuberculosis Reference Laboratory of Iran between 2011 and ***:The study evaluated the prevalence of NTM among specimens from patients with pulmonary tuberculosis symptoms(n=15771)deposited at the National Tuberculosis Reference Laboratory of Iran from 2011 to *** of Mycobacterium(M.)tuberculosis was based on presence of a 190-bp amplicon from IS6110 insertion sequence using Tb1 and Tb2 primers,and amplicon-negative specimens were tested for NTM and ***(refractory to IS6110 amplification)using restriction fragment length polymorphism PCR of hsp65 amplicon ***:A total of 7307(46.33%)*** and 658(4.17%)NTM specimens were found,the latter mainly comprising ***(10.18%),***(2.28%),***(8.97%),***(10.49%),***(4.71%),and ***(56.08%).Conclusions:As treatment for NTM differs from that for ***,accurate detection of Mycobacterium *** of public health significance.

关键词： Diagnosis Iran Non-tuberculosis Mycobacterium Prevalence

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Estimation of Depth to Salt Domes from Normalized Full Gradient of Gravity Anomaly and Examples from the USA and Denmark

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Journal of Earth Science 2009年第6期20卷 1012-1016页

作者： Hamid aghajani ali Moradzadeh 曾华霖 Faculty of Mining Petroleum and GeophysicsShahrood University of Technology School of Geophysics and Information Technology China University of GeosciencesBeijing

We present an estimation of depth of anomalous bodies using normalized full gradient （NFG） of gravity anomaly. Maxima in the NFG map can locate the bodies and indicate their depth. Model calculation using a sphere and application of the NFG method to gravity anomalies over salt domes in the USA and Denmark shows effectiveness of the method. However, the accuracy of depth estimation strongly depends on the number of term N in the Fourier series used to calculate the NFG. An optimum N for the calculation can be given from a test.

关键词： depth estimation anomalous body normalized full gradient gravity anomaly Fourier series.

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利用三维归一化总梯度法探测铁矿：以Ojatabad矿区为例

利用三维归一化总梯度法探测铁矿：以Ojatabad矿区为例

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中国地球物理学会第二十四届年会

作者： Hamid aghajani ali Moradzadeh 曾华霖陈召曦地下信息探测技术与仪器教育部重点实验室＜中国地质大学北京＞

＜正＞由前苏联地球物理学家别列兹金于20世纪60世纪末提出的重力归一化总梯度法,是一种利用重力场中的特征点（如极大点或者极小点）或者解析函数的极点,探测重力异常的场源体并估计其位置的方法。近几年来,中国学者把该方法用在油田...

＜正＞由前苏联地球物理学家别列兹金于20世纪60世纪末提出的重力归一化总梯度法,是一种利用重力场中的特征点（如极大点或者极小点）或者解析函数的极点,探测重力异常的场源体并估计其位置的方法。近几年来,中国学者把该方法用在油田藏勘探上取得了一定的效果,曾华霖教授通过建立非均匀密

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Thermal performance and entropy generation for nanofluid jet injection on a ribbed microchannel with oscillating heat flux:Investigation of the first and second laws of thermodynamics

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中国化学工程学报（英文版） 2022年第2期

作者： Yu-Liang Sun Davood Toghraie Omid ali Akbari Farzad Pourfattah As'ad alizadeh Navid Ghajari Mehran aghajani

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