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Numerical investigation of supercontinuum generation and optical frequency combs in Si N-based PCF with high nonlinear coefficient

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Optoelectronics Letters 2024年第3期20卷 163-170页

作者： Mohammad Reza alizadeh Mahmood Seifouri Saeed Olyaee Faculty of Electrical Engineering Shahid Rajaee Teacher Training UniversityTehranIran Nano-photonics and Optoelectronics Research Laboratory(NORLab) Shahid Rajaee Teacher Training UniversityTehranIran

In this paper, a photonic crystal fiber(PCF) with a dispersion-engineered and high nonlinear coefficient has been designed for supercontinuum generation(SCG) and frequency comb generation(FCG). The proposed PCF has a Si_(3)N_(4) rod in the core. This rod provides more optical confinement in the core by increasing the refractive index of the core. This high confinement reduces the effective mode area of PCF and thus increases the nonlinear coefficient.

关键词： optical fiber nonlinear

Chronic effects of stretching on range of motion with consideration of potential moderating variables:A systematic review with meta-analysis

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Journal of Sport and Health Science 2024年第2期13卷 186-194页

作者： Andreas Konrad Shahab alizadeh Abdolhamid Daneshjoo Saman Hadjizadeh Anvar Andrew Graham Ali Zahiri Reza Goudini Chris Edwards Carina Scharf David George Behm Institute of Human Movement Science Sport and HealthGraz UniversityGraz A-8010Austria School of Human Kinetics and Recreation Memorial University of NewfoundlandSt.John’sNL A1C 5S7Canada Department of Sport Injuries and Corrective Exercises Faculty of Sport SciencesShahid Bahonar University of KermanKerman 76169-13439Iran

Background:It is well known that stretch training can induce prolonged increases in joint range of motion(ROM).However,to date more information is needed regarding which training variables might have greater influence on improvements in ***,the purpose of this metaanalysis was to investigate the effects of stretch training on ROM in healthy participants by considering potential moderating variables,such as stretching technique,intensity,duration,frequency,and muscles stretched,as well as sex-specific,age-specific,and/or trained state-specific adaptations to stretch ***:We searched through PubMed,Scopus,Web of Science,and SportDiscus to find eligible studies and,finally,assessed the results from 77 studies and 186 effect sizes by applying a random-effect ***,by applying a mixed-effect model,we performed the respective subgroup *** find potential relationships between stretch duration or age and effect sizes,we performed a ***:We found a significant overall effect,indicating that stretch training can increase ROM with a moderate effect compared to the controls(effect size=-1.002;Z=-12.074;95%confidence interval:-1.165 to-0.840;p<0.001;I^(2)=74.97).Subgroup analysis showed a significant difference between the stretching techniques(p=0.01)indicating that proprioceptive neuromuscular facilitation and static stretching produced greater ROM than did ballistic/dynamic ***,there was a significant effect between the sexes(p=0.04),indicating that females showed higher gains in ROM compared to ***,further moderating analysis showed no significant relation or ***:When the goal is to maximize ROM in the long term,proprioceptive neuromuscular facilitation or static stretching,rather than ballistic/dynamic stretching,should be *** to consider in future research as well as sports practice is that neither volume,intensity,nor frequency of stretching were

关键词： Flexibility Long-term stretching Stretch training

Microbiome as an endocrine organ and its relationship with eye diseases:Effective factors and new targeted approaches

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World Journal of Gastrointestinal Pathophysiology 2024年第5期15卷 1-18页

作者： Leila Haghshenas Sara Banihashemi yalda Malekzadegan Roberto Catanzaro Amir Moghadam Ahmadi Francesco Marotta Department of Clinical Bioinformatics Harvard Medical SchoolBostonMA 02115United States Department of Bioscience School of Science and TechnologyNottingham Trend UniversityNottingham NG14FQUnited KingdomDepartment of BioscienceSchool of Science and TechnologyNottingham Trend UniversityNottingham NG14FQUnited Kingdom Department of Microbiology Saveh University of Medical SciencesSaveh ***Iran Department of Clinical and Experimental Medicine University of CataniaCatania 95123CataniaItaly Department of Neuroimmunology Thomas Jefferson University HospitalPhiladelphiaPA 19107United States Department of Human Nutrition and Food Sciences Texas Women UniversityMilano 20154Italy

Microbiome is an endocrine organ that refers to both the complicated biological system of microbial species that colonize our bodies and their genomes and *** studies confirm the connection between the microbiome and eye diseases,which are involved in the pathogenesis of eye diseases,including age-related macular disorders,diabetic retinopathy,glaucoma,retinitis pigmentosa,dry eye,and *** aim of this review is to investigate the microbiome in relation to eye ***,a brief introduction of the characteristics of the gut microorganisms terms of composition and work,the role of dysbiosis,the gut microbiome and the eye microbiome in the progression of eye illnesses are highlighted,then the relationship among the microbiome and the function of the immune system and eye diseases,the role of inflammation and aging and the immune system,It has been reviewed and finally,the control and treatment goals of microbiome and eye diseases,the role of food factors and supplements,biotherapy and antibiotics in relation to microbiome and eye health have been reviewed.

关键词： Dysbiosis Gut microbiome Eye diseases Inflammation Diabetic retinopatyhy Aging Nutrient supplementation

Structural and Mechanical Properties of Al/B_4C Composites Fabricated by Wet Attrition Milling and Hot Extrusion

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Journal of Materials Science & Technology 2013年第8期29卷 725-730页

作者： Morteza alizadeh Mostafa alizadeh Rasool Amini Department of Materials Science and Engineering Shiraz University of TechnologyModarres Blvd.71555-313 ShirazIran Department of Metals Institute of Materials Science and EngineeringGraduate University of Advanced TechnologyP.O.Box 76315-115KermanIran

In this study, Al matrix composites reinforced by 7.5 and 15 vol.% B4C particles and also monolithic Al （Al without the B4C particles） were produced by wet attrition milling and subsequent hot forward extrusion processes. The microstructure of the composites, evaluated by scanning electron microscopy （SEM）, showed that the B4C particles were properly distributed in the Al matrix. Mechanical properties of the Al/B4C composites and monolithic Al were investigated by tensile, wear and hardness tests, The results revealed that with increasing content of B4C particles, the tensile strength and microhardness of composites increased but the elongation decreased. In addition, the tensile strength and microhardness of composite samples were higher than those of monolithic Al. The density measurements revealed that the density of composites decreased with increasing content of the B4C particles.

关键词： Composites Mechanical properties Attrition milling Hot extrusion

Finite element analysis of controlled low strength materials

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Frontiers of Structural and Civil Engineering 2019年第5期13卷 1243-1250页

作者： Vahid alizadeh Gildart Haase School of Computer Sciences & Engineering Fairleigh Dickinson UniversityTeaneckNJ 07666USA

Controlled low strength materials (CLSM) are flowable and self-compacting construction materials that have been used in a wide variety of applications. This paper describes the numerical modeling of CLSM fills with finite element method under compression loading and the bond performance of CLSM and steel rebar under pullout loading. The study was conducted using a plastic-damage model which captures the material behavior using both classical theory of elasto-plasticity and continuum damage mechanics. The capability of the finite element approach for the analysis of CLSM fills was assessed by a comparison with the experimental results from a laboratory compression test on CLSM cylinders and pullout tests. The analysis show's that the behavior of a CLSM fill w'hile subject to a failure compression load or pullout tension load can be simulated in a reasonably accurate manner.

关键词： CLSM finite element method compressive strength pullout numerical modeling plastic damage model

AN IMPRINTED POLYMER FOR REMOVAL OF Cd^(2+) FROM WATER SAMPLES:OPTIMIZATION OF ADSORPTION AND RECOVERY STEPS BY EXPERIMENTAL DESIGN

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Chinese Journal of Polymer Science 2011年第6期29卷 658-669页

作者： Taher alizadeh Department of Applied Chemistry Faculty of ScienceUniversity of Mohaghegh ArdabiliArdabilIran

A new ion-imprinted polymer （liP） was synthesized by copolymerization of 4-vinylpyridine （monomer）, ethyleneglycoldimethacrylate （cross-linker） and 2,2-azobis-isobutyronitrile （initiator） in the presence of Cd2＋ and quinaldic acid （complexing agent）. It was found that the adsorption capacity of IIP and blank polymer were 45.0 and 6.2 mg g-l, respectively. The relative selectivity coefficients of the imprinted polymer for different binary mixture were also calculated. Compared to non-imprinted polymer （NIP）, the IIP had higher selectivity for Cd（II）. The IIP was used as a sorbent for cadmium extraction from water samples by using a simple batch extraction procedure. The effect of different parameters on Cd2＋ extraction and its recovery from the IIP were evaluated and optimized by using experimental design methodology. The optimized adsorption/desorption procedure was applied for cadmium removal from the real water samples. The obtained recoveries proved that this IIP could be used for removal of trace cadmium ions from water samples.

关键词： Cd2+ removal Ion imprinted polymer Solid phase extraction Experimental design

Numerical prediction of hydrodynamic cavitating flow structures and their corresponding erosion

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Journal of Hydrodynamics 2021年第3期33卷 546-571页

作者： Amirhossein Mohammadkhani Mansour alizadeh Department of Mechanical Engineering Iran University of Science and TechnologyTehranIran

Hydrodynamic cavitating flows usually consist of 3-D intense vortical flows that are detached from solid *** vortical flows normally generate heaps of cavitating flow structures,which,in turn,govern the location of cavitation erosion before ***,this study introduces a new numerical approach based on the improved delayed detached eddy simulation(IDDES)turbulence modeling for predicting cavitating ***,the solution of compressible Eulerian-Eulerian two-phase flow and the IDDES turbulence model was linked to the microjet hypothesis and unsteady behavior of pressure and vapor volume to predict the corresponding erosion of cavitating *** method for cavitation erosion prediction,a modified version taken from previous studies,was applied as a post-processing *** validation of cavitating flow predictions was performed for the first time on the Grenoble axisymmetric nozzle by comparing them with 21 photos of cavitation from the previous experimental *** results showed that the present numerical approach estimated various features of hydrodynamic cavitation well,including shedding processes and the length,shape,and collapse of cavitating *** the numerical analysis,three main stages were detected for the present cavitating flow,and the vorticity-cavitation interactions were investigated by the vorticity transport *** streak-like and tube-like cavitating(STLIC and TULIC)structures were introduced in the second stage,initiated by flow instability,and entirely governed by corresponding turbulent flow *** collapse of these cavitating structures is one of the primary sources of cavitation erosion on lower and upper *** results of the numerical erosion predictions were compared with those of the previous erosion tests on the Grenoble axisymmetric *** numerical performance was achieved in predicting the location and intensity of cavitation erosion.

关键词： Turbulent and cavitating structures cavitation erosion detached vortical flow Hybrid RANS-LES turbulence modeling flow instability flow visualization

An Investigation into the Magnetic Properties of Nickel Nano-grains Synthesized Via Thermal Decomposition Techniques

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Chinese Journal of Chemistry 2011年第6期29卷 1119-1123页

作者： Malakooti, Reihaneh Takhti, yalda Mirzajani, Roya Nanochemistry Research Laboratory Department of Chemistry University of Birjand Birjand Iran P. O. BOX 97175615 Iran Department of Chemistry Shahid Chamran University of Ahvaz Ahvaz Iran

Nickel nanoparticles were synthesized through the thermal decomposition of nickel（II） acetylacetonate in con- junction with the two methods of hot-injection and heating-up at elevated temperatures in alkylamine. Using several mole ratios of the oleic acid, different morphologies were obtained. The synthesized particles were characterized via XRD, SEM, TEM, SAED and EDAX. Mean particle size was revealed to range from 25 to 45 nm. Presence of crystallized particles in HCP with little FCC phases was also confirmed with XRD patterns. Magnetic hysteresis loops measured by the VSM showed that the magnetic properties of Ni nanoparticles （i.e., coercivity, saturation magnetization and relative permeability） were much enhanced in comparison with the bulk.

关键词： hot-injection heating-up nickel

A multiscale spatio-temporal framework to regionalize annual precipitation using k-means and self-organizing map technique

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Journal of Mountain Science 2018年第7期15卷 1481-1497页

作者： Kiyoumars ROUSHANGAR Farhad alizadeh Department of Water Resources Engineering Faculty of Civil EngineeringUniversity of Tabriz

Determination of homogenous precipitation-based regions is a very important task in effective management of water resources. The present study tried to propose an effective precipitation-based regionalization methodology by conjugating both temporal pre-processing and spatial clustering approaches in a way to take advantage of multiscale properties of precipitation time series. Annual precipitation data of 51 years(1960-2010) for 31 rain gauges(RGs) were collected and used in proposed clustering approaches. Discreet wavelet transform(DWT) was used to capture the time-frequency attributes of the time series and multiscale regionalization was performed by using k-means and Self Organizing Maps(SOM) clustering techniques. Daubechies function(db) was selected as mother wavelet to decompose the precipitation time series. Also, proper boundary extensions and decomposition level were applied. Different combinations of the approximation(A) and detail(D) coefficients were used to determine the input dataset as a basis of spatial clustering. The proposed model's efficiency in spatial clustering stage was verified using three different indexes namely, Silhouette Coefficient(SC), Dunn index and Davis Bouldin index(DB). Results approved superior performance of k-means technique in comparison to SOM. It was also deduced that DWT-based regionalization methodology showed improvements in comparison to historical-based models. Cross mutual information was used to investigate the RGs of cluster 3's homogeneousness in DWT-k-means approach. Results of non-linear correlation approach verified homogeneity of cluster 3. Verifications based on mean annual precipitation values of rain gauges in each cluster also approved the capability of multiscale approach in precipitation regionalization.

关键词： Precipitation Discrete wavelet transform (DWT) k-means Self Organizing Map(SOM) Iran