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Acta Geochimica 2021年第5期40卷 752-772页

作者： Batoul Taghipour Somayeh Shabani alireza k somarin Department of Earth Sciences Faculty of SciencesShiraz UniversityShirazIran Department of Geology Brandon UniversityBrandonMBCanada

The Nain ophiolite complex with an extent of[600 km2 is a part of the Central Iranian ophiolite,which is related to the opening and subsequent closure of the Neo-Tethys *** and serpentinized harzburgite in the Nain area host podiform chromitites that occur as three(eastern Hajhossein,western Hajhossein,and Soheil Pakuh)schlieren-type tabular and aligned massive lenses with various *** most common chromitite ore textures are massive,nodular,disseminated,and banded,reflecting crystal settling *** Cr#[Cr/(Cr+Al)]ranges from 0.43 to 0.81(average 0.63).The Mg#[Mg/(Mg+Fe2+)]varies from 0.25 to 0.78(average0.62).The Nain ophiolite and hosted chromitite are generally characterized by high Cr#,reflecting crystallization from a very hot boninite magma in a MORB *** high Cr#in the Nain chromitite also indicates a high degree of melting(15%–35%)of the depleted *** average total PGE content in the ophiolitic host rock(harzburgite and dunite)and chromite are 107 and 221 ppb,*** Nain ophiolite and chromitite have high IPGE/PPGE and negative Pt*(Pt/Pt*=0.6)anomaly,which is a characteristic of high Cr#*** U-shaped REE pattern of dunite host rock suggests the interaction of depleted mantle peridotite with boninitic *** data suggest that the Nain chromitites are related to the boninitic magma emplacement in a suprasubduction zone.

关键词： Nain chromitite Platinum group elements Ushaped REE pattern Boninitic magma Supra-subduction zone

Massive Dirac particles based on gapped graphene with Rosen-Morse potential in a uniform magnetic field

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Chinese Physics B 2024年第8期33卷 170-178页

作者： A.kalani alireza Amani M.A.Ramzanpour Department of Physics Ayatollah Amoli BranchIslamic Azad UniversityAmolIran

We explore the gapped graphene structure in the two-dimensional plane in the presence of the Rosen-Morse potential and an external uniform magnetic *** order to describe the corresponding structure,we consider the propagation of electrons in graphene as relativistic fermion quasi-particles,and analyze it by the wave functions of two-component spinors with pseudo-spin symmetry using the Dirac ***,to solve and analyze the Dirac equation,we obtain the eigenvalues and eigenvectors using the Legendre differential *** that,we obtain the bounded states of energy depending on the coefficients of Rosen-Morse and magnetic potentials in terms of quantum numbers of principal n and spin-orbit ***,the values of the energy spectrum for the ground state and the first excited state are calculated,and the wave functions and the corresponding probabilities are plotted in terms of coordinates *** what follows,we explore the band structure of gapped graphene by the modified dispersion relation and write it in terms of the two-dimensional wave vectors k_(x) and k_(y).Finally,the energy bands are plotted in terms of the wave vectors k_(x) and k_(y) with and without the magnetic term.

关键词： massive Dirac equation Rosen–Morse potential Legendre polynomial gapped graphene pseudospin symmetry

Hydrodynamic Assessment of A New Nature-Based Armour Unit on Rubble Mound Breakwater for Coastal Protection

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China Ocean Engineering 2024年第3期38卷 439-452页

作者： Ehsan SAFA alireza MOJTAHEDI Abdolmajid MOHAMMADIAN Mohamad Ali Lotfollahi YAGHIN Department of Water Resources Engineering Faculty of Civil EngineeringUniversity of TabrizTabriz ***Iran Faculty of Civil Engineering University of OttawaOttawa K1H 8M5Canada

This research proposes a novel nature-based design of a new concrete armour unit for the cover layer of a rubblemoundbreakwater. Armour units are versatile with respect to shape, orientation, surface condition details, and ***, a detailed analysis is required to investigate the exact state of their hydraulic interactions and structuralresponses. In this regard, the performance results of several traditional armour units, including the Antifer cube,Tetrapod, X-block and natural stone, are considered for the first step of this study. Then, the related observed resultsare compared with those obtained for a newly designed (artificial coral) armour unit. The research methodology utilizesthe common wave flume test procedure. Furthermore, several verified numerical models in OpenFOAM code areused to gain the extra required data. The proposed armour is configured to provide an effective shore protection as anenvironmental-friendly coastal structure. Thus it is designed with a main trunk including deep grooves to imitate thetypical geometry of a coral type configuration, so as to attain desirable performance. The observed results and ananalytic hierarchy process (AHP) concept are used to compare the hydraulic performance of the studied traditionaland newly proposed (artificial coral) armour units. The results indicate that the artificial coral armour unit demonstratesacceptable performance. The widely used traditional armour units might be replaced by newer designs for betterwave energy dissipation, and more importantly, for fewer adverse effects on the marine environment.

关键词： rubble mound breakwater hydraulic interaction armour unit analytic hierarchy process numerical model

Nanofabricated high turn-density spiral coils for on-chip electromagneto-optical conversion

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Microsystems & Nanoengineering 2024年第2期10卷 181-192页

作者： Ilhan Bok alireza Ashtiani Yash Gokhale Jack Phillips Tianxiang Zhu Aviad Hai Department of Biomedical Engineering University of Wisconsin–MadisonMadisonWIUSA Department of Electrical and Computer Engineering University of Wisconsin–MadisonMadisonWIUSA Wisconsin Institute for Translational Neuroengineering(WITNe) University of Wisconsin–MadisonMadisonWIUSA

Circuit-integrated electromagnets are fundamental building blocks for on-chip signal transduction,modulation,and tunability,with specific applications in environmental and biomedical micromagnetometry.A primary challenge for improving performance is pushing quality limitations while minimizing size and fabrication complexity and retaining spatial *** efforts have exploited highly involved three-dimensional synthesis,advanced insulation,and exotic material ***,we present a rapid nanofabrication process that employs electron beam dose control for high-turn-density diamond-embedded flat spiral coils;these coils achieve efficient on-chip electromagnetic-to-optical signal *** fabrication process relies on fast 12.3 s direct writing on standard poly(methyl methacrylate)as a basis for the metal lift-off *** with 70 micrometer overall diameters and 49–470 nm interturn spacings with corresponding inductances of 12.3–12.8 nH are *** utilize optical micromagnetometry to demonstrate that magnetic field generation at the center of the structure effectively correlates with finite element modeling *** designs based on our process can be integrated with photolithography to broadly enable optical magnetic sensing and spin-based computation.

关键词： utilize retaining high

An Improved Coupled Level Set and Continuous Moment-of-Fluid Method for Simulating Multiphase Flows with Phase Change

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1034-1069页

作者： Zhouteng Ye Cody Estebe Yang Liu Mehdi Vahab Zeyu Huang Mark Sussman alireza Moradikazerouni kourosh Shoele Yongsheng Lian Mitsuhiro Ohta M.Yousuff Hussaini ZJUI Institute Zhejiang UniversityHaining 314400ZhejiangChina Department of Mathematics Florida State UniversityTallahasseeUSA Department of Mechanical Engineering Florida State UniversityTallahasseeUSA Mechanical and Aerospace Engineering Mathworks NatickMAUSA School of Aerospace Engineering Tsinghua UniversityBeijing 100084China Department of Mechanical Engineering University of LouisvilleLouisvilleUSA Department of Mechanical Science Tokushima UniversityTokushimaJapan

An improved algorithm for computing multiphase flows is presented in which the multimaterial Moment-of-Fluid(MOF)algorithm for multiphase flows,initially described by Li et al.(2015),is enhanced addressing existing MOF difficulties in computing solutions to problems in which surface tension forces are crucial for understanding salient flow *** Continuous MOF(CMOF)method is motivated in this *** CMOF reconstruction method inherently removes the"checkerboard instability"that persists when using the MOF method on surface tension driven multiphase(multimaterial)*** CMOF reconstruction algorithm is accelerated by coupling the CMOF method to the level set method and coupling the CMOF method to a decision tree machine learning(ML)*** flow examples are shown in the two-dimensional(2D),three-dimensional(3D)axisymmetric"RZ",and 3D coordinate *** include two material and three material multiphase flows:bubble formation,the impingement of a liquid jet on a gas bubble in a cryogenic fuel tank,freezing,and liquid lens dynamics.

关键词： Moment-of-Fluid(MOF) Surface tension Two phase flow Phase change Deforming boundaries with change(s)in topology Two-dimensional(2D) Three-dimensional(3D)axisymmetric 3D

Sensitivity Analysis of Pollutants and Pattern Factor in a Gas Turbine Model Combustor due to Changes in Stabilizing Jets Characteristics

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Journal of Thermal Science 2022年第5期31卷 1622-1641页

作者： BAZDIDI-TEHRANI Farzad TEYMOORI alireza GHIYASI Mehdi School of Mechanical Engineering Iran University of Science and TechnologyTehran16846-13114Iran

In the present paper,a sensitivity analysis of pollutants and pattern factor in a model combustor due to changes in the geometrical characteristics of stabilizing jets has been carried *** exhaust pollutants including NO_(x),CO and soot have been chosen due to their harmful effect on the *** pattern factor has been also considered owing to its impact on turbine *** geometrical characteristics comprise diameter,angle and position of stabilizing ***-Lagrangian approach has been employed to model liquid fuel injection and distribution,breakup and evaporation of *** the analysis of reactive-spray flow characteristics,RANS approach,realizable k-εturbulence model,discrete ordinates radiative heat transfer model and steady flamelet combustion model together with the chemical reaction mechanism of diesel fuel(C_(10)H_(22))have been ***_(x) modeling has been performed via *** analysis is such that by making variations in the problem inputs(diameter,angle and position of jets)in an organized manner,the effects on the outputs(NO_(x),CO,soot and pattern factor)are *** number and order of simulations are predicted by design of experiments and full factorial *** have been analyzed using analysis of *** has been observed that if interactions among the characteristics of jets are considered,it is possible to analyze the exhaust pollutants more *** fact,by using the interactions,it is likely to find a point where all output parameters are *** show that by considering interactions of stabilizing jet characteristics,the maximum values of NO_(x),CO,soot and pattern factor change from 13.927 ppm,11.198%mole fraction,2.877 ppm and 0.043 to 26.233 ppm,14.693%mole fraction,142.357 ppm and 0.060,***,the minimum values change from 5.819 ppm,7.568%mole fraction,0.013 ppm and 0.029 to 6.098 ppm,5.987%mole fraction,0.002 ppm and 0.027,respectively.

关键词： model jet-stabilized combustor liquid fuel injection sensitivity analysis design of experiments pollutants pattern factor

Data envelopment analysis for scale elasticity measurement in the stochastic case:with an application to Indian banking

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Financial Innovation 2023年第1期9卷 955-990页

作者： alireza Amirteimoori Biresh k.Sahoo Saber Mehdizadeh Faculty of Engineering&Natural Sciences Istinye UniversityIstanbulTurkey Xavier Institute of Management XIM UniversityBhubaneswar 7571013India

In the nonparametric data envelopment analysis literature,scale elasticity is evaluated in two alternative ways:using either the technical efficiency model or the cost efficiency *** evaluation becomes problematic in several situations,for example(a)when input proportions change in the long run,(b)when inputs are heterogeneous,and(c)when firms face ex-ante price uncertainty in making their production *** address these situations,a scale elasticity evaluation was performed using a value-based cost efficiency ***,this alternative value-based scale elasticity evaluation is sensitive to the uncertainty and variability underlying input and output ***,in this study,we introduce a stochastic cost-efficiency model based on chance-constrained programming to develop a value-based measure of the scale elasticity of firms facing data *** illustrative empirical application to the Indian banking industry comprising 71 banks for eight years(1998–2005)was made to compare inferences about their efficiency and scale *** key findings are as follows:First,both the deterministic model and our proposed stochastic model yield distinctly different results concerning the efficiency and scale elasticity scores at various tolerance levels of chance ***,both models yield the same results at a tolerance level of 0.5,implying that the deterministic model is a special case of the stochastic model in that it reveals the same efficiency and returns to scale characterizations of ***,the stochastic model generates higher efficiency scores for inefficient banks than its deterministic ***,public banks exhibit higher efficiency than private and foreign ***,public and old private banks mostly exhibit either decreasing or constant returns to scale,whereas foreign and new private banks experience either increasing or decreasing returns to *** the application of our proposed stochastic mode

关键词： Data envelopment analysis Stochastic data envelopment analysis Technical efficiency Returns to scale Economies of scale Scale elasticity Indian banking Econometrics Economics

A mixed acid methodology to produce thermally stable cellulose nanocrystal at high yield using phosphoric acid

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Journal of Bioresources and Bioproducts 2022年第2期7卷 17-26页

作者： khairatun Najwa Mohd Amin alireza Hosseinmardi Darren J.Martin Pratheep k.Annamalai Australian Institute for Bioengineering and Nanotechnology(AIBN) the University of QueenslandBrisbaneQLD 4072 Australia Faculty of Chemical and Process Engineering Technology College of Engineering TechnologyUniversiti Malaysia PahangLebuhraya Tun Razak26300 Gambang KuantanPahang D.M.Malaysia

Cellulose nanocrystal(CNC)with distinctive shape-morphology,enhanced thermal stability and dispersibility is essential for overcoming the challenges in processing polymer/CNC nanocom-posites through melt compounding at elevated *** study shows a mixed acid hy-drolysis method to produce CNC with improved thermal stability and high *** use of phosphoric acid(H_(3)PO_(4)),as a mild acid,in combination with a strong acid either sulphuric acid(H_(2)SO_(4))or hydrochloric acid(HCl)leads to reduced use of strong acids and low impact on our *** influences of acid combination and sequence of addition on the production yield were investigated by retaining the proportion of H_(3)PO_(4)to corrosive acid(H_(2)SO_(4)and HCl)4 to 1,and solid to liquid ratio 1꞉*** methodology has enabled to isolate CNC with higher thermal stability,dispersibility and productivity in terms of amount acid used 1 g of CNC,as compared with single acid *** CNC produced using the combination of H_(3)PO_(4)and HCl exhibits high thermal stability,dispersibility and rod-like shape morphology with length and width of(424±86)and(22±3)nm,***,this approach has reduced H_(3)PO_(4)consumption by 54%as compared with single acid hydrolysis method for the production of same amount of CNC.

关键词： Cellulose nanocrystal(CNC) Acid hydrolysis Thermal stability Mixed acid Crystallinity Production yield

Glucose measurement via Raman spectroscopy of graphene:Principles and operation

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Nano Research 2022年第10期15卷 8697-8704页

作者： alireza Ahmadianyazdi Ngoc Hoang Lan Nguyen Jie Xu Vikas Berry Department of Mechanical and Industrial Engineering University of Illinois at ChicagoChicagoIllinois 60607USA Department of Chemical Engineering University of Illinois at ChicagoChicagoIllinois 60607USA

The sensitivity of graphene’s Raman characteristics to external perturbations can be exploited for sensing *** apply this principle,Raman spectroscopy of graphene in contact with a chemical/biological analyte is recorded to unravel a correlation between analyte’s physical/chemical/biological properties and electronic properties(Fermi energy and dopants level)of *** an example,we demonstrate the principle and operation of glucose measurement using graphene’s Raman spectroscopy,utilizing both affinity and enzymatic detection *** the affinity detection,we monitor Raman spectrum of graphene in contact with a glucose containing sample to quantify the attachment of glucose onto 1-pyrene boronic acid(PBA)functionalized *** is revealed that glucose covalent bond to PBA induces n-type doping in graphene and increases its Fermi level following the Hill–Langmuir *** the enzymatic detection,we show that graphene’s Fermi energy shifts due to the biocatalytic oxidation of glucose by immobilized glucose oxidase(GOx)*** a result,graphene becomes p-doped with increasing glucose *** attribute this sensitivity to a re-distribution of ionic charges within the electric double layer(EDL)of graphene upon introducing the glucose *** model explains both our affinity and enzymatic glucose detection *** glucose detection,our graphene Raman spectroscopy-based sensor(GRS)may extend its applications to a broader range of remote and non-invasive detection without the need to employ electronics such as field-effect transistors.

关键词： graphene Raman spectroscopy glucose affinity detection glucose oxidase

The effects of fire and seasonal variations on soil properties in Juniperus excelsa *** 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 *** 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%,***,when burned sites were compared to unburned sites,the activities of acid phosphatase(ACP) and urease enzymes increased by 73% and 12%,***,fire did not affect soil texture,bulk density(BD),pH,electric conductivity(EC),exchangeable potassium(kexc),or the activities of alkaline phosphatase(ALP) and *** 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 ***,phosphorous and dehydrogenase activity were significantly different in selected soil factors at 0-10 and10-20 cm *** interaction of fire,season,and soil depth were significant for phosphorous and ***,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 *** a stands had either improved or remained unaffected,returning to pre-fire ***,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