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Journal of Central South University 2016年第1期23卷 122-129页

作者： alireza rahbari Department of Mechanical Engineering Shahid Rajaee Teacher Training University (SRTTU)

A numerical model is presented to investigate the performance of homogeneous charge compression ignition(HCCI) engines fueled with ethanol. Two approaches are studied. On one hand, two-step reaction mechanisms with Arrhenius reaction rates are implemented in combustion chemistry modeling. On the other hand, a reduced mechanism containing important reactions of ethanol involving heat release rate and reaction rates compatible with experimental data is employed. Since controls of combustion phenomenon and ignition timing are the main issues of these engines, the effects of inlet temperature and equivalence ratio as the controlling factors on the operating parameters such as ignition timing, burn duration, in-cylinder temperature and pressure of HCCI engines are explored. The results show that the maximum predicted pressures for thermodynamic model are about 71.3×10~5 Pa and 79.79×10~5 Pa, and for chemical kinetic model, they are about 71.48×10~5 Pa and 78.123×10~5 Pa, fairly comparable with corresponding experimental values of 72×10~5 Pa and 78.7×10~5 Pa. It is observed that increasing the initial temperature advances the ignition timing, decreases the burn duration and increases the peak temperature and pressure. Moreover, the maximum temperature and pressure are associated with richer mixtures.

关键词： HCCI发动机进气温度乙醇燃料当量比数值研究性能影响点火正时控制化学动力学模型

Analytical Model for Predicting the Heat Loss Effect on the Pyrolysis of Biomass Particles

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Chinese Journal of Chemical Engineering 2013年第10期21卷 1114-1120页

作者： alireza rahbari Fatemeh Ebrahiminasab Mehdi Bidabadi Department of Mechanical Engineering Shahid Raj aee Teacher Training University (S RTTU) Tehran lran Deigartment of Mechanical Englneering. Iran University of Science and Technology Combustion Research LaboratoryNarmak Tehran Iran

This paper presents the combined influence of heat-loss and radiation on the pyrolysis of biomass particles by considering the structure of one-dimensional, laminar and steady state flame propagation in uniformly premixed wood particles. The assumed flame structure consists of a broad preheat-vaporization zone where the rate of gas-phase chemical reaction is small, a thin reaction zone composed of three regions: gas, tar and char combustion where convection and the vaporization rate of the fuel particles are small, and a broad convection zone. The analysis is performed in the asymptotic limit, where the value of the characteristic Zeldovich number is large and the equivalence ratio is larger than unity(i.e.u≥1). The principal attention is made on the determination of a non-linear burning velocity correlation. Consequently, the impacts of radiation, heat loss and particle size as the determining factors on the flame temperature and burning velocity of biomass particles are declared in this research.

关键词：颗粒结构生物质热损失预测模型热解气相化学反应燃烧速度蒸发速率

CFD study of non-premixed swirling burners: Effect of turbulence models

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Chinese Journal of Chemical Engineering 2020年第4期28卷 1029-1038页

作者： Erfan Khodabandeh Hesam Moghadasi Mohsen Saffari Pour Mikael Ersson Par G.Jonsson Marc A.Rosen alireza rahbari Department of Mechanical Engineering Amirkabir University of TechnologyTehranIran School of Mechanical Engineering Department of Energy ConversionIran University of Sciesnce and Technology(IUST)Narmak 16846-13114TehranIran Department of Mechanical Engineering Shahid Bahonar University of KermanKermanIran Division of Processes Department of Materials Science and EngineeringKTH Royal Institute of TechnologyBrinellvägen 23SE-10044 StockholmSweden Faculty of Engineering and Applied Science University of Ontario Institute of TechnologyOshawaOntarioL1H 7K4Canada Department of Mechanical Engineering Shahid Rajaee Teacher Training University(SRTTU)TehranIran Research School of Engineering The Australian National UniversityCanberraACT 2601Australia

This research investigates a numerical simulation of swirling turbulent non-premixed *** effects on the combustion characteristics are examined with three turbulence models:namely as the Reynolds stress model,spectral turbulence analysis and Re-Normalization *** addition,the P-1 and discrete ordinate(DO)models are used to simulate the radiative heat transfer in this *** governing equations associated with the required boundary conditions are solved using the numerical *** accuracy of this model is validated with the published experimental data and the comparison elucidates that there is a reasonable agreement between the obtained values from this model and the corresponding experimental *** different models proposed in this research,the Reynolds stress model with the Probability Density Function(PDF)approach is more accurate(nearly up to 50%)than other turbulent models for a swirling flow *** the effect of radiative heat transfer model,it is observed that the discrete ordinate model is more precise than the P-1 model in anticipating the experimental *** model is able to simulate the subcritical nature of the isothermal flow as well as the size and shape of the internal recirculation induced by the swirl due to combustion.

关键词： Computational Fluid Dynamics(CFD) Turbulent combustion Non-premixed flames Large eddy simulations Radiative heat transfer model Modeling validation

Tidal modeling based on satellite altimetry observations of TOPEX/ Poseidon, Jason1, Jason2, and Jason3 with high prediction capability: A case study of the Baltic Sea

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Geodesy and Geodynamics 2024年第4期15卷 404-418页

作者： alireza A.Ardalan Asiyeh Hashemifaraz School of Surveying and Geospatial Engineering College of EngineeringUniversity of TehranTehran 11155-4563Iran

This research aims to optimize the utilization of long-term sea level data from the TOPEX/Poseidon,Jason1,Jason2,and Jason3 altimetry missions for tidal *** generate a time series of along-track observations and apply a developed method to produce tidal models with specific tidal constituents for each *** tidal modeling methodology follows an iterative process:partitioning sea surface height(SSH)observations into analysis/training and prediction/validation parts and ultimately identi-fying the set of tidal constituents that provide the best predictions at each time series *** study focuses on developing 1256 time series along the altimetry tracks over the Baltic Sea,each with its own set of tidal *** of the developed tidal models against the sSH observations within the prediction/validation part reveals mean absolute error(MAE)values ranging from 0.0334 m to 0.1349 m,with an average MAE of 0.089 *** same validation process is conducted on the FES2014 and EOT20 global tidal models,demonstrating that our tidal model,referred to as BT23(short for Baltic Tide 2023),outperforms both models with an average MAE improvement of 0.0417 m and 0.0346 m,*** addition to providing details on the development of the time series and the tidal modeling procedure,we offer the 1256 along-track time series and their associated tidal models as supplementary *** encourage the satellite altimetry community to utilize these resources for further research and applications.

关键词： Satellitealtimetry Baltic Sea Ocean tide modeling Jason3 Jason2 Jason1 TOPEX/Poseidon EOT20 FES2014

Prevalence of Anemia in Patients with Diabetes Mellitus:A Systematic Review and Meta-Analysis

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Biomedical and Environmental Sciences 2024年第1期37卷 96-107页

作者： Monireh Faghir-Ganji Narjes Abdolmohammadi Maryam Nikbina alireza Amanollahi alireza Ansari-Moghaddam Rozhan Khezri Hamidreza Baradaran Student Research Committee Iran University of Medical SciencesTehranIran Department of Epidemiology School of Public HealthIran University of Medical SciencesTehranIran Department of Epidemiology School of Public HealthTehran University of Medical SciencesTehranIran Department of Midwifery Shoushtar Faculty of Medical SciencesShoushtarIran Department of Epidemiology School of Public Health and SafetyShahid Beheshti University of Medical SciencesTehranIran Trauma and Injury Research Center Iran University of Medical SciencesTehranIran Health Promotion Research Center Zahedan University of Medical SciencesZahedanIran Endocrine Research Center Institute of Endocrinology and MetabolismIran University of Medical SciencesTehranIran

Objective Anemia is a common public health concern in patients with type 2 diabetes *** study aimed to identify the prevalence of anemia among patients with *** Electronic databases,including PubMed,Scopus,Web of Sciences,and Google Scholar,were searched systematically for studies published between 2010 and *** removing duplicates and inappropriate reports,the remaining manuscripts were reviewed and appraised using theNewcastleOttawa Scale(NOS)tool.A random-effects model was used to calculate the pooled estimates of the extracted data using Stata version *** of the studies was assessed using the Q *** A total of 51 articles containing information on 26,485 patients with diabetes were included in this *** articles were mainly from Asia(58.82%)and Africa(35.29%).The overall prevalence of anemia was 35.45%(95%CI:30.30–40.76),with no evidence of heterogeneity by *** the two continents with the highest number of studies,the prevalence of anemia in patients with diabetes was significantly higher in Asia[40.02;95%CI:32.72–47.54]compared to Africa[28.46;95%CI:21.90–35.50](P for heterogeneity=0.029).Moreover,there has been an increasing trend in the prevalence of anemia in patients with diabetes over time,from[15.28;95%CI:9.83–22.21]in 2012 to[40.70;95%CI:10.21–75.93]in *** Globally,approximately 4 in 10 patients with diabetes suffer from ***,routine anemia screening and control programs every 3 months might be useful in improving the quality of life of these patients.

关键词： Prevalence Diabetic foot Anemia Diabetes mellitus

Distributed Energy and Reserve Scheduling in Local Energy Communities Using L-BFGS Optimization

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 942-952页

作者： Mohammad Dolatabadi alireza Zakariazadeh Alberto Borghetti Pierluigi Siano Department of Management&Innovation Systems University of SalernoSalernoItaly Department of Electrical Electronicand Information EngineeringUniversity of BolognaBolognaItaly University of Science and Technology of Mazandaran BehshahrIran Department of Power Systems National University of Science and Technology POLITEHNICA BucharestBucharestRomania IEEE

Encouraging citizens to invest in small-scale renewable resources is crucial for transitioning towards a sustainable and clean energy *** energy communities(LECs)are expected to play a vital role in this ***,energy scheduling in LECs presents various challenges,including the preservation of customer privacy,adherence to distribution network constraints,and the management of computational *** paper introduces a novel approach for energy scheduling in renewable-based LECs using a decentralized optimization *** proposed approach uses the Limitedmemory Broyden–Fletcher–Goldfarb–Shanno(L-BFGS)method,significantly reducing the computational effort required for solving the mixed integer programming(MIP)*** incorporates network constraints,evaluates energy losses,and enables community participants to provide ancillary services like a regulation reserve to the grid *** assess its robustness and efficiency,the proposed approach is tested on an 84-bus radial distribution *** indicate that the proposed distributed approach not only matches the accuracy of the corresponding centralized model but also exhibits scalability and preserves participant privacy.

关键词： Distributed optimization flexibility services L-BFGS method local energy community renewables reserve

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

Synergistic effect of adsorption and photocatalytic degradation of oilfield-produced water by electrospun photocatalytic fibers of Polystyrene/Nanorod-Graphitic carbon nitride

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Journal of Environmental Sciences 2024年第7期141卷 287-303页

作者： Parisa Azmoon Mehrdad Farhadian alireza Pendashteh Amir H.Navarchian Department of Chemical Engineering Faculty of EngineeringUniversity of IsfahanIsfahanIran Department of Chemical Engineering Faculty of EngineeringUniversity of GuilanRashtIran Department of Water and Environmental Engineering Caspian Sea Basin Research CenterUniversity of GuilanRashtIran

Graphitic carbon nitride with nanorod structure(Nr-GCN)was synthesized using melamine as a precursor without any other reagents by hydrothermal pretreatment ***,FTIR,SEM,N_(2)adsorption-desorption from BET,UV-Vis DRS spectroscopy,and photoluminescence were used to characterize the prepared ***,the photoelectrochemical behavior of nanoparticles was studied by photocurrent transient response and cyclic voltammetry ***(PS)fibrous mat was fabricated by electrospinning technique and used as a support for the stabilization of the *** performance of the synthesized nanoparticles and photocatalytic fibers(PS/Nr-GCN)was evaluated in oilfield-produced water treatment under visible light *** this process,oil contaminants were adsorbed by hydrophobic polystyrene fibers and simultaneously degraded by *** removal efficiency of chemical oxygen demand(COD)has been obtained 96.6%and 98.4%by Nr-GCN and PS/Nr-GCN,respectively,at the optimum conditions of pH4,photocatalyst dosage 0.5 g/L,COD initial concentration 550 mg/L,and illumination time 150 *** gas chromatography-mass spectroscopy analysis results showed 99.3%removal of total petroleum hydrocarbons using photocatalytic fibers of PS/*** results demonstrated that the GCN has outstanding features like controllable morphology,visible-light-driven,and showing high potential in oily wastewater ***,the synergistic effect of adsorption and photocatalytic degradation is an effective technique in oilfield-produced water treatment.

关键词： Graphitic carbon nitride(GCN) Nanorod structure Polystyrene fibrous mat Photocatalytic fibers Oilfield-produced water(OPW)

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

One-step pore diffusion mechanism of Li+ in solid electrolyte interphase for fast-charging lithium-ion battery

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Rare Metals 2024年第7期43卷 3438-3440页

作者： Shan Wang Shu-Yuan Liu alireza Khataee Ke-Zhen Qi College of Pharmacy Dali University Research Laboratory of Advanced Water and Wastewater Treatment Processes Department of Applied ChemistryFaculty of ChemistryUniversity of Tabriz Peoples' Friendship University of Russia (RUDN University)

Li+transport in solid electrolyte interphase is recognized as important factor,which has become a research ***,an one-step pore diffusion mechanism for Li+transport through solid electrolyte interphase was proposed,which was different from previous two-step *** one-step pore diffusion process could effectively eliminate the dynamic limitations of Li+transport in solid electrolyte interphase （SEI） for rapid charging *** work will contribute to the development of rapid charging lithium-ion batteries.

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