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Observational Hubble parameter data constraints on the interactive model of f(T) gravity with particle creation

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Chinese Physics C 2022年第12期46卷 288-297页

作者： S.Ganjizadeh alireza amani M.A.Ramzanpour Department of Physics Ayatollah Amoli BranchIslamic Azad UniversityAmolIran

In this study,we consider an open system from the thermodynamic perspective for an adiabatic FRW universe model in which particle creation occurs within the *** this case,the modified continuity equation is obtained,and then,we make it correspond to the continuity equation of f(T)***,we take f(T)gravity with a viscous fluid in the flat-FRW metric,where T is the torsion *** assume the contents of the universe to be dark matter and dark energy and consider an interaction term between *** interesting point of this study is that we make the modified continuity equation resulting from particle creation equivalent to the matter continuity equation resulting from f(T)*** result of this evaluation establishes a relationship between the number of particles and scale *** what follows,we write the corresponding cosmological parameters in terms of the number of particles and also reconstruct the number of particles in terms of the redshift *** then parameterize the Hubble parameter derived from power-law cosmology with 51 data points from the Hubble observational parameter ***,we plot the corresponding cosmological parameters for dark energy in terms of the redshift to investigate the accelerated expansion of the *** addition,by using the sound speed parameter,we discuss the stability and instability analyses of the present model in different eras of the ***,we plot the density parameter values for dark energy and dark matter in terms of the redshift parameter.

关键词： equation of state parameter f(T)gravity viscous fluid particle creation stability analysis

Modified White Hole Enthalpy Coupled to Quantum Bose-Einstein Condensate at Extremely Low Entropy

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Journal of Modern Physics 2023年第12期14卷 1587-1599页

作者： Amos S. Kubeka alireza amani Mantile Lekala Department of Mathematical Sciences University of South Africa Pretoria South Africa Department of Physics Ayatollah Amoli Branch Islamic Azad University Amol Iran Department of Physics University of South Africa Pretoria South Africa

We model the universe as a white hole, and in the process we perform detailed analysis of the enthalpy equation of the modified white hole, and we get a much detailed picture of when and how did;quantum gravity (cosmology) phase, inflationary phase, and the acceleration phase of the universe happened. We determine the field equations of the modified white hole and evolve the scale factor and compare the evolution to the thermodynamic properties of the universe. We also illustrate that the strong energy condition is violated, but both the null energy condition and the strong cosmic censorship are not violated. Lastly, we couple the enthalpy to the Bose-Einstein condensate at extremely low entropy at the quantum gravity (cosmology) regime. Thereafter, we determine the unstable condition of the Bose-Einstein quantum equation which we interpret as the moment when the big bang occurred.

关键词： Modified White Hole Quantum Bose-Einstein Condensate Enthalpy Energy Density Stability Analysis Strong Cosmic Censorship

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基于非球面镜的双视场全景环带成像系统

基于非球面镜的双视场全景环带成像系统

作者： amani alireza（艾利）浙江大学

学位级别：硕士

全景成像技术是一种对360°周边环境进行直接检测与成像的技术。该系统具有结构紧凑、无需移动部件和高分辨成像的特性,在机器人视觉、管道探测等领域具有广阔的应用前景。目前,大多数全景成像相机采用一系列折反光学镜片。比如鱼眼镜头... 详细信息

全景成像技术是一种对360°周边环境进行直接检测与成像的技术。该系统具有结构紧凑、无需移动部件和高分辨成像的特性,在机器人视觉、管道探测等领域具有广阔的应用前景。目前,大多数全景成像相机采用一系列折反光学镜片。比如鱼眼镜头,虽然可以覆盖280°的宽视场,但在成像方面有很大的缺点,主要体现为不均匀的像面照度以及随视场而变化的不均衡分辨率。由于折射法成像所能提供的视场压缩能力有限,超大视场的全景成像一般采用全景环带系统（Panoramic Annular Lens,PAL）来实现。但由于其光路特性,全景环带系统存在以下缺陷:1)由于全景透镜块状头部单元的第二反射表面遮挡了来自系统正前方的入射光线,使得其成像面的中心区域存在一块无法与外部物点共轭的圆形盲区,既降低了图像探测器的使用效率,又给使用者带来视觉上的不适感;2)由于全景系统需要在有限成像面积上完成对超大视场的成像工作,获取的图像分辨率往往比较低,无法对局部细节进行成像。在此背景下,本文提出了基于非球面镜的双视场全景环带成像系统,该系统能够消除全景系统中心盲区,提高局部细节的成像分辨率,同时增强系统结构紧凑度。由于偶次非球面元件具有比较大的设计自由度,在超大视场全景成像系统中使用偶次非球面,可以缩小或彻底消除全景系统的盲区,并且可以利用更少的光学元件实现系统像差的校正,实现局部放大功能。本文基于单视点（Single View Point,SVP）全景环带光学系统的成像特性,提出并设计了一种紧凑型折反射式全景环带成像系统。首先,基于几何光学光线追迹法和单视点模型建立了全景前端单元结构的数学模型。并利用该数学模型设计了单视点全景环带光学系统光学的全景前端单元结构（Panoramic Front Unit,PFU）。在此基础上利用Zemax-OpticStudio光学设计软件,结合偶次非球面,设计了和PFU匹配的后继透镜组（Relay Lens Group,RL）。PFU和RL两者结合,构成了一款紧凑型无盲区全景环带系统,实现了全景环带光学系统盲区的消除、像质的提升和结构的简化。本文的研究内容主要包括以下几个方面:1)建立了基于单视点模型的全景前端单元结构的数学模型传统的鱼眼镜头采用透射式结构,利用负透镜实现对超大视场光线的压缩。这一压缩过程导致在成像过程中该系统具有无法回避的较大边缘畸变,进而导致边缘视场下成像分辨率的下降。因此,采用折反射结构可以有效地解决这一问题。折反射式超大视场全景环带成像系统由全景块状头部单元（PFU）和后继透镜系统组成（RL）,光线在全景块状头部单元内完成两次反射,并由后继透镜系统校正像差。这一结构不仅使得超大视场光线的获取更加容易,而且使得系统在大视场下畸变恶化的情况得到改善。同时折射结构也使得光学系统变得更加紧凑,有利于系统的小型化发展。虽然折反射式超大视场全景环带成像系统的视场范围可以接近甚至超过半球,但是由于反射结构的存在,会损失镜头正前方的部分视场,只能将环绕光学系统周围360°空间范围内的物体按柱面投影规律一次性成像于二维环形平面上。为了解决上述问题,可以将一种称为全向镜（Omnidirectional Mirrors）的新型光学结构与相机联合使用,实现对前向视场和周向视场光线的同时采集,从而克服了传统折反式全景镜头具有盲区的缺点。通常,全向镜与传统成像系统的组合称为全向折反射系统（Omnidirectional Catadioptric System,OCS）,其水平视场角可以达到360°,垂直视场可以全部覆盖甚至超过半球。当全向镜满足单视点的限制条件时,系统进化为单视点全景成像系统,可以进一步将全景三维图转换成标准的投影图,方便实现图像处理,便于工程中的实际应用。本文从单视点（SVP）的限制条件入手,介绍了单视点的基本概念以及如何建立单视点全景视觉系统的数学模型。具有单视点的反射面应该满足:经过一个点的所有的主光线,经过光学系统后,全部汇聚于另一点。常见的具有单视点的反射镜包括椭球面反射镜、双曲面反射镜和抛物面反射镜。在一个大视场折反射系统中,通常希望具有单视点,即唯一的视场投影中心。在该处设置孔径光阑,可以轻松的对不同视场成像光束的光束口径进行调控,实现细光束成像,进而使得超大视场成像成为可能。此外,在该处设置孔径光阑还可以滤除视场外的杂散光。当后继镜组将不同视场的成像光线投影在探测器上时,每一个像素可以看作对应于经过单视点的一条入射主光线,此时投影关系明确。通过柱状投影关系,可以将采集到的环形图像展开映射为二维平面图像。为了实现消盲区的头部单元结构设计,需要使得前向视场光线能够通过头部单元而不影响周向视场的采集。基于单视点的全景镜头数学模型能够清晰描述不同视场的光线路径,可以很好地为前向视场光线窗口预留出空间。2)基于全景前端单元结构

关键词：双视场折反射式全景环带成像系统单视点偶次非球面匹兹凡系数 f-θ畸变机器人自主导航品质函数编辑器

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二极管阵列检测器波长校准方法研究及评价

中国测试 2018年第7期44卷 19-24页

作者：杨三东艾利封娇唐涛王风云郝青丽李彤南京理工大学江苏南京210094 大连依利特分析仪器有限公司辽宁大连116023

波长校准是二极管阵列检测器研制过程中一个重要的环节,可直接影响到光谱定性定量的准确度。利用原位光源——氘灯的特征光谱结合氧化钬玻璃的透过光谱对二极管阵列检测器进行波长校准,比较波长标准值的取值方式以及校准方程的拟合方式... 详细信息

波长校准是二极管阵列检测器研制过程中一个重要的环节,可直接影响到光谱定性定量的准确度。利用原位光源——氘灯的特征光谱结合氧化钬玻璃的透过光谱对二极管阵列检测器进行波长校准,比较波长标准值的取值方式以及校准方程的拟合方式对校准结果的影响,并使用偏差平均值、偏差标准差、均方根误差对校准结果进行评价。结果表明,多点高次函数拟合的校准结果更准确,其中多点三次函数校准结果的偏差平均值、偏差标准差、均方根误差分别是–2.97×10^(–3) nm、0.47 nm、0.44 nm。对自制光电二极管阵列检测器进行波长校准,波长误差在±1 nm以内。

关键词：光谱波长校准方法原位光源二极管阵列检测器

Isogeometric analysis of coupled thermo-elastodynamic problems under cyclic thermal shock

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Frontiers of Structural and Civil Engineering 2019年第2期13卷 397-405页

作者： Asghar amani DASHLEJEH Faculty of Engineering University of Mohaghegh ArdabiliIran

The isogeometric analysis (IGA) method was extended for the solution of the coupled thermoelastodynamic equations. The dimensionless formulation was accepted in discretization of the uncoupled and coupled thermoelasticity equations and the Generalized Newmark method was used in the time integration procedure. First, the performance of the proposed method was verified against a two-dimensional benchmark example subjected to constant thermal shock with available exact analytical solutions. Then a two-dimensional half^space benchmark example under thermal shock was solved. Finally, cyclic thermal shock (CTS) loading was applied on the half-space problem. The results dedicated that IGA can be used as a suitable approach in the analysis of the general thermomechanical problems.

关键词： isogeometric analysis coupled thermo-elastodynamic dynamic analysis generalized newmark cyclic thermal

Recrystallization and mechanical properties of WE43 magnesium alloy processed via cyclic expansion extrusion

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International Journal of Minerals,Metallurgy and Materials 2018年第6期25卷 672-681页

作者： Soheil amani Ghader Faraji School of Mechanical Engineering College of Engineering University of Tehran

In this study, cyclic expansion extrusion（CEE）, as a relatively new severe plastic deformation（SPD） process, is applied to a rare earth（RE） containing Mg alloy WE43. The effects of the processing temperature and the number of passes are also investigated. The results showed that dynamic recrystallization（DRX） occurred after CEE processing at 400°C, and a bimodal structure with ultrafine DRXed grains surrounded the unrecrystallized grains. However, the DRX at 330°C was retarded because of the existence of RE elements. The tensile tests showed that a simultaneous increase in the strength and the ductility of WE43 is obtained after CEE processing at 400°C via two passes. Furthermore, the highest ultimate tensile strength of 440 MPa was achieved after the second pass of CEE at 330°C, and the highest ductility of 21% was attained after the second pass of CEE at 400°C. The microhardness measurements showed that the hardness increased from HV 80 to HV 114 and HV 98 after two passes of CEE processing at 330 and 400°C, respectively. In conclusion, increasing the processing passes could increase the mechanical properties and the volume fraction of the recrystallized grains. Moreover, increasing the temperature reduced the strength and the microhardness even if the elongation increased.

关键词： severe plastic deformation (SPD) grain refinement mechanical properties WE43 microhardness deformation behavior

Design aspect of a novel L-shaped pulsed column for liquid–liquid extraction applications: Energy consumption and the characteristics velocity concept

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Chinese Journal of Chemical Engineering 2018年第4期26卷 723-730页

作者： Pouria amani Elham Mohammadi Sahar Akhgar School of Chemical Engineering College of Engineering University of Tehran Chemical Engineering Department Tarbiat Modares University

This article deals with the evaluation of the consumption of energy for a steady state solvent extraction in a novel L-shaped pulsed sieve-plate column, which is highly required for design and optimization of the periodic flow processes for industrial applications. In this regard, a comprehensive evaluation on the energy consumption in case of a pulsed flow for three different chemical systems is conducted and besides the influence of pulsation intensity, the effect of geometrical parameters including the plate spacing and the plate free area is investigated as well. Moreover, the concept of characteristic velocity models at flooding points is evaluated with respect to the variation of pressure drop along the column at different operational conditions.

关键词： Solvent extraction Pulsed plate column Pressure drop Energy consumption Pulsed flow Characteristic velocity

A novel combined baffle-cavity micro-combustor configuration for Micro-Thermo-Photo-Voltaic applications

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Chinese Journal of Chemical Engineering 2020年第2期28卷 403-413页

作者： E.amani A.Daneshgar A.Hemmatzade Mechanical Engineering Dept. Amirkabir University of TechnologyTehranIran

The major issues of Micro-Thermo-Photo-Voltaic(MTPV) micro-combustors are flame instabilities, which narrow the operational range, and non-uniform wall temperature, which lowers the overall efficiency. The purpose of the present research is to propose a novel micro-combustor with combined baffle and cavity configuration to address these issues. For this aim, a numerical modeling approach is validated and used. The performance of the improved combustor is compared with another recent baffle-bluff configuration. It is shown that the novel design improves the average wall temperature by 36.4 K and mitigates its standard deviation by 13.4 K. Moreover, using the optimal baffle thickness, these enhancements can be augmented by 4% raise of average wall temperature, 62%increase of temperature uniformity, and 20% reduction in overall emission. The baffle length of 0.6 times the combustor length and thickness of 0.0625 times the baffle spacing result in the optimal operation due to the flame lift-off in the upstream direction. According to the sensitivity analysis, the most effective geometrical parameters are the baffle length and thickness. It is expected that using this novel micro-combustor with optimized design parameters improves the overall efficiency of MTPV systems.

关键词： Microscale Computational Fluid Dynamics(CFD) Reaction Micro-combustion Micro-Thermo-Photo-Voltaic(MTPV) Emission

Synthesis and Crystal Structure of 2-(4-Chlorophenyl)-1,4,5-triphenyl-1H-imidazole

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Chinese Journal of Structural Chemistry 2012年第4期31卷 574-576页

作者： Ali Mohammad amani Kazem Barati Young Researchers Club Shiraz BranchIslamic Azad University Young Researchers Club Yasooj BranchIslamic Azad University

The compound 2-（4-chlorophenyl）-1,4,5-triphenyl-1H-imidazole（1,C27H19ClN2） has been synthesized and its crystal structure was determined by single-crystal X-ray *** crystal of 1 belongs to the triclinic system,space group P with a = 10.3350（19）,b = 10.238（2）,c = 11.201（2） ,α = 85.957（16）,β = 83.148（15）,γ = 66.467（15）°,V = 1078.5（4） 3,Mr = 406.89,Z = 2,F（000） = 422,Dc = 1.257 g/cm3,μ = 0.193 mm-1,T = 298（2） K,S = 1.092,R = 0.0702 and wR = *** imidazole ring system is planar and makes a dihedral angle of 40.3° with the chlorobenzene ring.

关键词： crystal structure imidazole triclinic system