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Thin Film Evolution Equation for a Strained Anisotropic Solid Film on a Deformable Isotropic Substrate

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Journal of Applied Mathematics and Physics 2018年第4期6卷 864-879页

作者： Wondimu Tekalign agegnehu atena Department of Mathematics Savannah State University Savannah GA USA

We consider a continuum model for the evolution of an epitaxially-strained dislocation-free anisotropic thin solid film on isotropic deformable substrate in the absence of vapor deposition. By using a thin film approximation we derived a nonlinear evolution equation. We examined the nonlinear evolution equation and found that there is a critical film thickness below which every film thickness is stable and a critical wave number above which every film thickness is stable.

关键词： Thin Films Evolution Equation Anisotropy Hooke’s Law

The Most Irrational Number that Shows up Everywhere: The Golden Ratio

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Journal of Applied Mathematics and Physics 2023年第4期11卷 1185-1193页

作者： Jiwon Choi agegnehu atena Wondimu Tekalign Department of Biology Savannah State University Savannah GA USA Department of Mathematics Savannah State University Savannah GA USA

Since the time of the ancient Greeks, humans have been aware of this mathematical idea. Golden ratio is an irrational number that is symbolized by the Greek numeral phi (φ). One can find this ratio everywhere. It is in nature, art, architecture, human body, etc. But this symbolism can result in a strong connection with mathematical nature. In this paper we will be discussing the connection between Fibonacci sequence (a series of numbers where every number is equal to the sum of two numbers before it) and Golden ratio. Secondly, how this mathematical idea shows up in a nature, such as sunflower and human DNA.

关键词： The Golden Ratio Fibonacci Sequence Nature

Steady State Gas Flow in Pipeline Networks: Existence and Uniqueness of Solution

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Journal of Applied Mathematics and Physics 2020年第6期8卷 1155-1167页

作者： agegnehu atena Wondimu Tekalign Tilahun Muche Department of Mathematics Savannah State University Savannah GA USA

In this paper we discuss the uniqueness and existence of solution to a real gas flow network by employing graph theory. A directed graph is an efficient way to represent a gas network. We consider steady state real gas flow network that includes pipelines, compressors, and the connectors. The pipelines and compressors are represented as edges of the graph and the interconnecting points are represented as nodes of the graph representing the network. We show that a unique solution of such a system exists. We use monotonicity property of a mapping to proof uniqueness, and the contraction mapping theorem is used to prove existence.

关键词： Gas Flow Network Uniqueness Existence

SYNTHESIS AND CHARACTERIZATION OF OPTICALLY ACTIVE POLYAMIDES BASED ON 2-(1,3-ISOINDOLINEDIONE-2-YL)GLUTARIC ACID BY DIRECT POLYCONDENSATION

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Chinese Journal of Polymer Science 2010年第4期28卷 589-596页

作者： Khalil Faghihi Meisam Shabanian atena Izadkhah Organic Polymer Chemistry Research Laboratory Department of ChemistryFaculty of ScienceArak UniversityArak 38156Iran

Five new optically active polyamides （PAs） 6a-6e were prepared by direct polycondensation reaction of 2-（1,3- isoindolinedione-2-yl）-glutaric acid 4 as a new chiral diacid with various aromatic diamines 5a-Se in a medium consisting of triphenyl phosphite （TPP）, calcium chloride, pyridine （Py） and N-methyl-2-pyrrolidone （NMP）. The polycondensation reaction produced a series of polyamids 6a-6e in quantitative yields with inherent viscosities of 0.26-0.39 dL/g. The resulting polymers were fully characterized by means of ^1H-NMR, FT-1R spectroscopy, elemental analysis, inherent viscosity and specific rotation. Thermal properties of these polymers were investigated using thermal gravimetric analysis （TGA） and differential thermal gravimetry （DTG）. Phthalimide rings as a bulky pendent group in the polymer chains disturb the interchain and intrachain interactions and make these PAs readily soluble in polar, aprotic solvents such as N,N-dimethyl acetamide （DMAc）, N,N-dimethyl formamide （DMF）, dimethyl sulfoxide （DMSO）, N-methyl-2-pyrrolidone （NMP） and sulfuric acid.

关键词： Polyamide Optically active polymers Thermally stable polymers

Applying SMART Goal Intervention Leads to Greater Goal Attainment, Need Satisfaction and Positive Affect

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International Journal of Mental Health Promotion 2022年第6期24卷 869-882页

作者： Zeynab Bahrami atena Heidari Jacquelyn Cranney University of Tehran Tehran***Iran University of New South Wales Sydney2052Australia

Previous research suggests that planning interventions lead to increased goal attainment, while other researchsuggests that goal attainment leads to increased well-being. This research integrates these two sets of researchfindings by investigating the effectiveness of one goal planning intervention, the SMART goal program, on goalattainment, and thus need satisfaction and well-being, in university students. An experimental design across aone-week period was employed to test whether participants in the experimental group, who received the SMARTgoal instructions, better obtained their goal in comparison to control group participants who did not receive thosespecific instructions. Findings indicated that the SMART goal program led to greater rated goal attainment andneed satisfaction, but not greater subjective well-being (SWB). Nevertheless, one component of SWB, positiveaffect, was greater in the Experimental group. Type of individually chosen self-concordant goal content hadno impact on whether participants attained their goal.

关键词： SMART goal intervention goal attainment need satisfaction subjective well-being positive affect

Numerical investigation of the hydraulic fracturing mechanisms in oil sands

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Underground Space 2021年第2期6卷 195-216页

作者： Siavash Taghipoor Morteza Roostaei Arian Velayati atena Sharbatian Dave Chan Alireza Nouri Department of Civil and Environmental Engineering University of AlbertaCanada KGHM International 1010 Lorne StSudburyON P3C 4R9Canada RGL Reservoir Management Inc. 690842 StLeducAB T9E 0R8Canada

This paper presents a numerical investigation of hydraulic fracturing in oil sands during cold water injection by considering the aspects of both geomechanics and reservoir fluid *** to previous studies,the low shear strengths of unconsolidated or weakly consolidated sandstone reservoirs significantly influence the hydraulic fracturing ***,classical hydraulic fracture models cannot simulate the fracturing process in weak sandstone *** the current numerical models,the direction of a tensile fracture is predetermined based on in situ stress ***,the potential transformation of a shear fracture into a tensile fracture and the potential reorientation of a tensile fracture owing to shear banding at the fracture tip have not yet been addressed in the *** this study,a smeared fracture technique is employed to simulate tensile and shear fractures in oil *** model used combines many important fracture features,which include the matrix flow,poroelasticity and plasticity modeling,saturation-dependent permeability,gradual degradation of the oil sands as a result of dilative shear deformation,and the tensile fracturing and shear failure that occur with the simultaneous enhancement of ***,sensitivity analyses are also performed with respect to the reservoir and geomechanical parameters,including the apparent tensile strength and cohesion of the oil sands,magnitude of the minimum and maximum principal stress,absolute permeability and elastic modulus of the oil sands and ramp-up *** these analyses are performed to clarify the influences of these parameters on the fracturing response of the oil sands.

关键词： Smeared fracture Hydraulic fracturing Numerical simulation Oil sand

无溶剂条件下勃姆石纳米粒子一锅催化多组分合成3,4-二氢嘧啶-2-(1H)酮(英文)

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催化学报 2014年第3期35卷 362-367页

作者： Ali Keivanloo Mahdi Mirzaee Mohammad Bakherad atena Soozani School of Chemistry Shahrood University of Technology

A simple, green, and efficient synthesis protocol for the synthesis of 3,4-dihydropyrimidin-2-(1H)-ones using boehmite nanoparticles as catalyst was *** did not use any toxic metal catalysts or corrosive acidic *** me... 详细信息

关键词：颗粒催化剂一锅法合成纳米颗粒勃姆石硫酮嘧啶二氢无溶剂

非穿透性深度巩膜切除术+MMC Tenon囊下注射治疗开角型青光眼术后高阶像差变化的研究（英文）

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国际眼科杂志 2019年第11期19卷 1811-1818页

作者： Ali Mostafaei Nazli Taheri atena Latifi 大不里士医科大学循证医学研究中心眼科伊朗大不里士*** 大不里士医科大学Nikoukari眼科医院伊朗大不里士***

目的:研究开角型青光眼患者非穿透性深层巩膜切除术后高阶像差的变化。方法:研究包括20例患者20眼,其中10例为原发性开角型青光眼,10例为继发性开角型青光眼。患者术前接受非穿透性深层巩膜切除术,并辅以Tenon囊下注射(0.02%of MMC)。... 详细信息

目的:研究开角型青光眼患者非穿透性深层巩膜切除术后高阶像差的变化。方法:研究包括20例患者20眼,其中10例为原发性开角型青光眼,10例为继发性开角型青光眼。患者术前接受非穿透性深层巩膜切除术,并辅以Tenon囊下注射(0.02%of MMC)。术前及术后1、3mo用i-Trace分析仪测定角膜总高阶像差。每次随访时评估眼压(IOP)、最佳矫正视力(BCVA)和眼泡形态。手术的成功率分为完全成功、相对成功和失败。结果:术前IOP为24.05±3.07 mmHg,平均用药2.85±0.67次,随访3mo后,IOP为12.30±3.32 mmHg,平均用药0.70±0.98次。随访期间IOP均明显下降(P<0.001)。术后随访1mo,总高阶像差(HOT)均方根(RMS)和总球型像差值明显升高,3mo后下降。术后各时间段三叶肌和全眼昏迷样像差变化无统计学意义。术后1mo HOT RMS及球形角膜均明显增加,3mo随访后明显减少。术后角膜三叶肌变化与术前相比无统计学意义。患者年龄和IOP对HOT和角膜HOT的变化无显著影响。结论:深度巩膜切除术后1mo内角膜和眼部高阶像差增加,3mo后下降,与术前相比无统计学意义。在3mo随访时,患者的BCVA和等效球镜(SE)与术前相比无统计学差异。

关键词：高阶相差眼压丝裂霉素C 非穿透深层巩膜切除术

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TRS勒塞尔总体规划,地拉那,阿尔巴尼亚

世界建筑 2005年第10期 74-77页

作者： : Labics (Rome) + atena Labics事务所 atena事务所

工程总体构想基地面积:8万m2;总建筑面积:23万m2.勒塞尔总体规划涉及到该市区内一个较大范围的设计,离地拉那市中心很近.该区现在由一些花房所占据,是一块有待开发的空地,不在建筑师规划的范围之内.该地区的开发主要是以住宅为主,并有... 详细信息

工程总体构想基地面积:8万m2;总建筑面积:23万m2.勒塞尔总体规划涉及到该市区内一个较大范围的设计,离地拉那市中心很近.该区现在由一些花房所占据,是一块有待开发的空地,不在建筑师规划的范围之内.该地区的开发主要是以住宅为主,并有部分商业和公共设施.

关键词：总体构想阿尔巴尼亚规划塞尔 TRS 建筑面积公共设施待开发大范围市中心