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Mechanical Properties of All MoS_(2) Monolayer Heterostructures:Crack Propagation and Existing Notch Study

Computers, Materials & Continua 2022年第3期70卷 4635-4655页

作者： Reza khademi zahedi Naif Alajlan hooman khademi zahedi Timon Rabczuk Institiute of Structural Mechanics Bauhaus-Universit鋞WeimarWeimar99423Germany Department of Computer Engineering King Saud UniversityRiyadhSaudi Arabia Mechanical Engineering Department Islamic Azad UniversityNorth Tehran BranchIran

The outstanding thermal,optical,electrical and mechanical properties of molybdenum disolphide(MoS_(2))heterostructures make them exceptional candidates for an extensive area of applications.Nevertheless,despite considerable technological and academic interest,there is presently a fewinformation regarding the mechanical properties of these novel two-dimensional(2D)materials in the presence of the defects.In thismanuscript,we performed extensive molecular dynamics simulations on pre-cracked and pre-notched all-molybdenum disolphide(MoS_(2))heterostructure systems using ReaxFF force field.Therefore,we study the influence of several central-crack lengths and notch diameters on the mechanical response of 2H phase,1T phase and composite 2H/1T MoS_(2) monolayers with different concentrations of 1T phase in 2H phase,under uniaxial tensile loading at room temperature.Our ReaxFF models reveal that larger cracks and notches decrease the strength of all 2D MoS_(2) single-layer heterostructures.Additionally,for all studied crack and notch sizes,2H phase of MoS_(2) films exhibits the largest strength.Maximum tensile stress of composite 2H/1T MoS_(2) nanosheet with different concentrations are higher than those for the equivalent 1T phase,which implies that the pre-cracked composite structure is remarkably stronger than the equivalent 1T phase.The comparison of the results for cracked and notched all-MoS_(2) nanosheet heterostructures reveal that the load bearing capacity of the notched samples of monolayerMoS_(2) are higher than the cracked ones.

关键词： Molybdenum disulphide(MoS_(2)) molecular dynamics simulations uniaxial tension cracks notches

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Investigating peak stresses in fitting and repair patches of buried polyethylene gas pipes

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Frontiers of Structural and Civil Engineering 2020年第1期14卷 147-168页

作者： Reza khademi zahedi Pouyan ALIMOURI hooman khademi zahedi Mohammad SHISHESAZ Institute of Structural Mechanics Bauhaus-Universitat WeimarMariensrtaβe 15Weimar 99423Germany Mechanical Engineering Department Shahid Chamran University of AhvazAhvazIran Mechanical Engineering Department Islamic Azad UniversityNorth Tehran BranchIran

Nowadays,polyethylene composes a large number of natural gas distribution pipelines installed under the ground.The focus of the present contribution is two fold.One of the objectives is to investigate the applicability of polyethylene fittings in joining polyethylene gas pipes which are electrofused onto the pipe ends and buried under the ground,by estimating stress distribution using finite element method.The second objective is to study the effectiveness of polyethylene repair patches which are used to mend the defected pipelines by performing a finite element analysis to calculate peak stress values.Buried polyethylene pipelines in the natural gas industry,can be imposed by sever loadings including the soil-structure interaction,traffic load,soil’s column weight,internal pressure,and thermal loads resulting from daily and/or seasonal temperature changes.Additionally,due to the application of pipe joints,and repair patches local stresses superimposed on the aforementioned loading effects.The pipe is assumed to be made of PE80 resin and its jointing socket,and the repair patch is PE100 material.The computational analysis of stresses and the computer simulations are performed using ANSYS commercial software.According to the results,the peak stress values take place in the middle of the fitting and at its internal surface.The maximum stress values in fitting and pipe are below the allowable stresses which shows the proper use of introduced fitting is applicable even in hot climate areas of Ahvaz,Iran.Although the buried pipe is imposed to the maximum values of stresses,the PE100 socket is more sensitive to a temperature drop.Furthermore,all four studied patch arrangements show significant reinforcing effects on the defected section of the buried PE gas pipe to transfer applied loads.Meanwhile,the defected buried medium density polyethylene gas pipe and its saddle fused patch can resist the imposed mechanical and thermal loads of 22℃ temperature increase.Moreover,increasing the saddle fusion patch length to 12 inch

关键词： Ansys software polyethylene buried pipelines polyethylene joints polyethylene patches peak von Mises stress soil-pipe interaction temperature variation

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From non-scattering to super-scattering with Mie-tronics

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Photonics Research 2024年第4期12卷 608-624页

作者： hooman BARATI SEDEH NATALIA M.LITCHINITSER Department of Electrical and Computer Engineering Duke UniversityDurhamNorth Carolina 27708USA

Electric anapoles, arising from the destructive interference of primitive and toroidal electric dipole moments, have recently emerged as a fundamental class of non-scattering sources. On the other hand, super-scattering states represent the opposite regime wherein the scattering cross-section of a subwavelength particle exceeds the single-channel limit, leading to a strong scattering behavior. Here, we demonstrate that the interplay between the topology of light and the subwavelength scatterer can lead to these two opposite responses within an isolated alldielectric meta-atom. In particular, we present the emergence of a new non-scattering state, referred to as hybrid anapole, which surpasses conventional electric dipole anapoles by achieving a remarkable 23-fold enhancement in the suppression of far-field radiation and almost threefold enhancement in the confinement of electromagnetic energy inside the meta-atom. We also explore the role of particle orientation and its inversion symmetry in the scattering response and predict the possibility of switching between non-scattering and super-scattering states within the same platform. The presented study elucidates the role of light and matter topologies in the scattering response of subwavelength meta-atoms, uncovering two opposite regimes of light-matter interaction and opening new avenues in applications such as nonlinear optics and spectroscopy.

关键词： spectroscopy opposite dipole

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Shoaling Internal Solitary Waves and the Formation of Boluses

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Open Journal of Fluid Dynamics 2024年第2期14卷 65-82页

作者： hooman Enayati Brian T. Helenbrook Department of Mechanical Engineering Lafayette College Easton PA USA Department of Mechanical & Aerospace Engineering Clarkson University Potsdam NY USA

An internal solitary wave of elevation in a two-layer density stratified system of an incompressible, viscous and homogeneous fluid was studied. The run-up of a wave of elevation encountering different slopes was investigated numerically based on solving the continuity, Navier-Stokes and convective-diffusion equations within the Boussinesq approximation. The commercial software COMSOL Multiphysics was used to conduct the numerical simulations. For gradual shoals, a bolus formed that transported dense fluid up the shoal. The bolus disappeared when it reached its maximum height on the slope due to the draining of the dense fluid. Various shoal angles were simulated to detect the critical angle above which a bolus does not form. An angle of 30 or less resulted in the formation of a bolus. In addition, the simulations demonstrated that the size of the bolus induced by shallower slopes was larger and that the vertical height traveled by the bolus was insensitive to the slope of the shoal.

关键词： Internal Solitary Waves COMSOL Multiphysics Wave Breaking

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世界针灸学会联合会《针灸临床实践指南：胃食管返流病》推荐意见概述(英文)

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World Journal of Acupuncture-Moxibustion 2024年

作者：张雪萍周娟潘炜炳黄雪陈若菡刘镇文兰芯陈琛琛杨星月范乾白兴华 Amir hooman Kazemi 北京中医药大学针灸推拿学院北京市东城区安定门社区卫生服务中心北京中医药大学东直门医院中国人民解放军总医院京北医疗区北京市丰台区中医医院常熟市中医院德黑兰大学

《针灸临床实践指南：胃食管反流病》（WFAS 007.9-2023)是世界针灸学会联合会2023年10月9日正式发布的针灸临床实践指南，也是首个针灸治疗胃食管反流病的指南。本指南内容主要包含指南目的、范围、适用人群、适用环境；针灸治疗胃食... 详细信息

《针灸临床实践指南：胃食管反流病》（WFAS 007.9-2023)是世界针灸学会联合会2023年10月9日正式发布的针灸临床实践指南，也是首个针灸治疗胃食管反流病的指南。本指南内容主要包含指南目的、范围、适用人群、适用环境；针灸治疗胃食管反流病概况；指南制定过程和推荐意见。本文重点介绍指南的推荐意见。本指南的颁布和实施将有利于规范针灸治疗胃食管反流病，对针灸在该病治疗中的推广应用将起到积极作用。

关键词：临床实践指南胃食管反流病食管及胃肠动力抑酸治疗针灸

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Integrated Intelligent Electromagnetic Radiator Design for Future THz Communication:A Review

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Chinese Journal of Electronics 2022年第3期31卷 499-515页

作者： LU Xuyang Venkatesh Suresh Saeidi hooman Sengupta Kaushik UM-SJTU Joint Institute Shanghai Jiao Tong University Electrical and Computer Engineering Princeton University

Advances in 6 G communication changes how machines and humans interact. The blossom of new applications demands significantly higher data bandwidth while preserving the mobility and sustainability of electronic wireless communication systems. It also demands an integrable system that allows convenient interactions between communication units and signal processing units.A review of CMOS-based THz communication system solutions is presented, with a focus on novel systematic EM-circuit co-design philosophy. This review starts with a review of THz power generation, followed by the discussion of THz localization and THz beamforming for efficient high-throughput communication.

关键词： Terahertz Integrated circuits CMOS 6G MIMO

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Association of p53/p21 expression with cigarette smoking and prognosis in esophageal squamous cell carcinoma patients

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World Journal of Gastroenterology 2010年第39期16卷 4958-4967页

作者： Noushin Taghavi Firouzeh Biramijamal Masoud Sotoudeh Omeed Moaven hooman khademi Mohammad Reza Abbaszadegan Reza Malekzadeh Department of Medical Genetics National Institute of Genetic Engineering and Biotechnology Digestive Disease Research Center Tehran University of Medical SciencesShariati HospitalNorth Karegar Ave Division of Human Genetics Immunology Research CenterAvicenna Research InstituteMashhad University of Medical Sciences

factors,such as cigarette smoking,in esophageal squamous cell carcinoma(ESCC)in northeastern Iran,a region with a high incidence of ESCC.METHODS:The expression of p53 and p21 proteins was investigated immunohistochemically in tumor tissue from 80 ESCC patients and in 60 available paraffinembedded blocks of adjacent normal specimens from the cases,along with normal esophageal tissue from 80 healthy subjects.RESULTS:Positive expression of p53 protein was detected in 56.2%(45/80)of ESCC cases,and in none of the normal esophageal tissue of the control group(P<0.001).Furthermore,73.8%(59/80)of ESCC cases and 43.8%(35/80)of controls had positive expression of p21 protein(P<0.001).Cigarette smoking was significantly associated with p53 over-expression in ESCC cases(P=0.010,OR=3.64;95%CI:1.32-10.02).p21 over-expression was associated with poorer clinical outcome among the ESCC patients(P=0.009).CONCLUSION:Over-expression of p53 in association with cigarette smoking may play a critical role in ESCC carcinogenesis among this high-risk population of northeastern Iran.Furthermore,p21 over-expression was found to be associated with poor prognosis,specifically in the operable ESCC patients.

关键词： Esophageal squamous cell carcinoma p53 p21 Immunohistochemistry Survival Smoking

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The effects of fire and seasonal variations on soil properties in Juniperus excelsa M.Bieb.stands in the Alborz Mountains,Iran

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Journal of Forestry Research 2022年第5期33卷 1471-1479页

作者： Nasim Bagheri Delijani Alireza Moshki Mohammad Matinizadeh hooman Ravanbakhsh Elham Nouri Faculty of Desert Studies Semnan UniversitySemnanIran Dep.of Forestry in Arid Regions Faculty of Desert StudiesSemnan UniversitySemnanIran Agricultural Research Education and Extension Organization(AREEO)Research Institute of Forests and RangelandsTehranIran

This study was conducted in Juniperus excels a stands on the southern slopes of Iran’s Alborz Mountains,to determine the effects of fire and seasonal variations on soil physicochemical properties and enzyme activities.A total of 64 composite soil s amples were randomly collected in the spring and fall from two burned and unburned sites at depths of 0-10 and 10-20 cm.The results of a two-way ANOVA analysis indicate that fire increased the organic carbon(OC),total nitrogen(TN),and available phosphorus(P_(ava)) contents of the soil by 16%,59%,and 53%,respectively.Similarly,when burned sites were compared to unburned sites,the activities of acid phosphatase(ACP) and urease enzymes increased by 73% and 12%,respectively.Nevertheless,fire did not affect soil texture,bulk density(BD),pH,electric conductivity(EC),exchangeable potassium(Kexc),or the activities of alkaline phosphatase(ALP) and dehydrogenase.According to two-way ANOVA results,OC,TN,P_(ava),K_(exc),and EC values were significantly higher in the fall,whereas pH and ALP values were significantly higher in the spring.Additionally,phosphorous and dehydrogenase activity were significantly different in selected soil factors at 0-10 and10-20 cm depths.The interaction of fire,season,and soil depth were significant for phosphorous and urease.Moreover,the activity of ALP correlated well with pH(r=0.68),P(r=-0.74),OC(r=-0.53),and TN(r=-0.37),whereas the activity of ACP correlated significantly with OC(r=0.64) and TN(r=0.71).Two years after the fire,soil properties in J.excels a stands had either improved or remained unaffected,returning to pre-fire levels.Additionally,soil chemical properties varied significantly across sampling seasons,which should be considered when comparing and interpreting soil data in future research.

关键词： Dehydrogenase Acid&alkaline phosphatases Seasonal variations Soil physicochemical properties Urease

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Journal of Integrative Medicine 2023年第4期21卷 354-360页

作者： Amir Mohammad Jaladat Mahdi Alizadeh Vaghasloo Fatemeh Atarzadeh Mohammad Hossein Ayati Amir hooman Kazemi Emine Akin Mohammad Hashem Hashempur Department of Persian Medicine School of MedicineShiraz University of Medical SciencesShiraz ***Iran Department of Traditional Medicine School of Persian MedicineTehran University of Medical SciencesTehran ***Iran Department of History of Medicine School of Traditional MedicineTehran University of Medical SciencesTehran ***Iran International School Beijing University of Chinese MedicineBeijing 100029China Alkali Life Center Healthy Life&Consultancy and EducationAtas ehir-Istanbul 34750Turkey Research Center for Traditional Medicine and History of Medicine Department of Persian MedicineSchool of MedicineShiraz University of Medical SciencesShiraz ***Iran

Kaiy(medieval cautery)is an ancient method of heat therapy in traditional Persian medicine(TPM).Some of its important applications have been neglected during the medical revolution.Meanwhile,different treatment modalities that incorporate heat,including moxibustion,have progressed in traditional Chinese medicine.In this study,we reviewed the main TPM textbooks that were written specifically in the field of kaiy.We considered the traditional teachings in the context of contemporary information,gathered from the scientific literature about moxibustion and modern cauterization.Some surgical therapeutic indications of kaiy(e.g.,debridement and coagulative procedures)have been advanced by the innovation of electro-cauterization.However,those therapeutic applications that were based on the TPM humoral theory for relieving body coldness or myofascial pains—which are similar to moxibustion usages—have not received the same attention.Apart from the broad similarities of kaiy and moxibustion as thermal therapies with similar indications,there is a striking correspondence between kaiy point mapping and acupoints.Therefore,further research on different kaiy aspects is recommended.

关键词： Traditional Persian medicine Moxibustion Chinese medicine Kaiy Medieval cautery Fire acupuncture

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Scour around submarine pipes due to high-amplitude transient waves

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Water Science and Engineering 2020年第2期13卷 154-161页

作者： Hassan Vosoughi hooman Hajikandi Department of Civil Engineering Central Tehran BranchIslamic Azad UniversityTehran ***Iran

Estimation of scour dimensions below submarine pipelines is a vital step in designing offshore infrastructure.Extreme events like tsunami waves produce strong erosive forces below the underwater pipes,apt to create scour holes,jeopardizing the safety of the structure.Despite the importance of this issue,previous studies have mainly focused on steady flow cases,and the scour pattern below submarine pipes induced by high-amplitude transient waves has rarely been investigated.This paper reports the results of 40 experimental runs on transient wave-induced scour below a model pipe in a laboratory flume under a variety of initial conditions.The variables included the bed particle size and gradation,initial water depth,wave height,and slope of the bed layer.Waves were generated by a sudden release of water from a sluice gate,installed in the middle of the flume.A pressure transducer data acquisition system was used to record the wave heights at different time steps.The results indicate that,with a shallower initial depth of flow,the scour depth is relatively large.It was also found that there exists a direct correlation between the induced wave height and the size of the scour hole.It was observed that,in clear water conditions,the size of the scour hole in coarse sediments is smaller,while in live-bed conditions,larger scour holes are created in coarser sediments.It was also observed that at high wave amplitudes,the live-bed conditions are dominant,and consequently the bed elevation is altered.

关键词： Submarine pipe Scour hole Transient wave Flume experiment Live-bed condition Sediment

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