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A rapid and efficient method for the synthesis of 14H-dibenzo[α.j]xanthenes,aryl-5H-dibenzo[b.i]xanthene-5,7,12,14-(13H)-tetraone and 1,8-dioxooctahydroxanthenes by acidic ionic liquid

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Chinese Chemical Letters 2010年第7期21卷 761-764页

作者： abbas Rahmati Department of Chemistry University of IsfahanP.O.Box 81746-7344IsfahanIran

Various xanthenes have been synthesized by the condensation ofβ-naphthol,2-hydroxynaphthalene-1,4-dione or dimedone with various aldehydes in the presence of trifluoroacetic acid as catalyst in 1,1,3,3-N,N,N′,N′-te... 详细信息

关键词： Ionic liquid 14H-Dibenzo[α.j]xanthenes β-Naphthol 2-Hydroxynaphthalene-1 4-dione Dimedone

Mass transfer investigation and operational sensitivity analysis of aminebased industrial CO_2 capture plant

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Chinese Journal of Chemical Engineering 2019年第3期27卷 534-543页

作者： abbas Hemmati Hamed Rashidi Chemical Engineering Department Faculty of Energy Kermanshah University of Technology

In this article, the industrial process of CO_2 capture using monoethanolamine as an aqueous solvent was probed carefully from the mass transfer viewpoint. The simulation of this process was done using Rate-Base model, based on two-film theory. The results were validated against real plant data. Compared to the operational unit, the error of calculating absorption percentage and CO_2 loading was estimated around 2%. The liquid temperature profiles calculated by the model agree well with the real temperature along the absorption tower, emphasizing the accuracy of this model. Operational sensitivity analysis of absorption tower was also done with the aim of determining sensitive parameters for the optimized design of absorption tower and optimized operational conditions. Hence,the sensitivity analysis was done for the flow rate of gas, the flow rate of solvent, flue gas temperature, inlet solvent temperature, CO_2 concentration in the flue gas, loading of inlet solvent, and MEA concentration in the solvent. CO_2 absorption percentage, the profile of loading, liquid temperature profile and finally profile of CO_2 mole fraction in gas phase along the absorption tower were studied. To elaborate mass transfer phenomena, enhancement factor, interfacial area, molar flux and liquid hold up were probed. The results show that regarding the CO_2 absorption, the most important parameter was the gas flow rate. Comparing liquid temperature profiles showed that the most important parameter affecting the temperature of the rich solvent was MEA concentration.

关键词： Carbon dioxide Monoethanolamine Rate-base model Enhancement factor Sensitivity analysis

A GIS-based time-dependent seismic source modeling of Northern Iran

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Earthquake Engineering and Engineering Vibration 2017年第1期16卷 33-45页

作者： Mahdi Hashemi Ali asghar Alesheikh Mohammad Reza Zolfaghari School of Information Seiences University of Pittsburgh Pittsburgh Pennsylvania 15260 USA Department of Geospatial Information Systems K.N. Toosi University of Technology Tehran 19697 Iran Civil Engineering Department K.N. Toosi Universiry of Technology Tehran 19697 Iran

： The first step in any seismic hazard study is the definition of seismogenic sources and the estimation of magnitude-frequency relationships for each source. There is as yet no standard methodology for source modeling and many researchers have worked on this topic. This study is an effort to define linear and area seismic sources for Northern Iran. The linear or fault sources are developed based on tectonic features and characteristic earthquakes while the area sources are developed based on spatial distribution of small to moderate earthquakes. Time-dependent recurrence relationships are developed for fault sources using renewal approach while time-independent frequency-magnitude relationships are proposed for area sources based on Poisson process. GIS functionalities are used in this study to introduce and incorporate spatial- temporal and geostatistical indices in delineating area seismic sources. The proposed methodology is used to model seismic sources for an area of about 500 by 400 square kilometers around Tehran. Previous researches and reports are studied to compile an earthquake/fault catalog that is as complete as possible. All events are transformed to uniform magnitude scale; duplicate events and dependent shocks are removed. Completeness and time distribution of the compiled catalog is taken into account. The proposed area and linear seismic sources in conjunction with defined recurrence relationships can be used to develop time-dependent probabilistic seismic hazard analysis of Northern Iran.

关键词： seismic source modeling geostatistical index seismic hazard GIS

Multi-verse Optimizer with Rosenbrock and Diffusion Mechanisms for Multilevel Threshold Image Segmentation from COVID-19 Chest X-Ray Images

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Journal of Bionic Engineering 2023年第3期20卷 1198-1262页

作者： Yan Han Weibin Chen Ali asghar Heidari Huiling Chen Department of Computer Science and Artificial Intelligence Wenzhou UniversityWenzhou325035China School of Surveying and Geospatial Engineering College of EngineeringUniversity of TehranTehranIran

Coronavirus Disease 2019(COVID-19)is the most severe epidemic that is prevalent all over the *** quickly and accurately identifying COVID-19 is of great significance to controlling the spread speed of the ***,it is essential to accurately and rapidly identify COVID-19 lesions by analyzing Chest X-ray *** we all know,image segmentation is a critical stage in image processing and *** achieve better image segmentation results,this paper proposes to improve the multi-verse optimizer algorithm using the Rosenbrock method and diffusion mechanism named *** utilizes RDMVO to calculate the maximum Kapur’s entropy for multilevel threshold image *** image segmentation scheme is called *** ran two sets of experiments to test the performance of RDMVO and ***,RDMVO was compared with other excellent peers on IEEE CEC2017 to test the performance of RDMVO on benchmark ***,the image segmentation experiment was carried out using RDMVO-MIS,and some meta-heuristic algorithms were selected as *** test image dataset includes Berkeley images and COVID-19 Chest X-ray *** experimental results verify that RDMVO is highly competitive in benchmark functions and image segmentation experiments compared with other meta-heuristic algorithms.

关键词： COVID-19 Multilevel threshold image segmentation Kapur’s entropy Multi-verse optimizer Meta-heuristic algorithm Bionic algorithm

Prediction of bed load sediments using different artificial neural network models

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Frontiers of Structural and Civil Engineering 2020年第2期14卷 374-386页

作者： Reza ASHEGHI Seyed abbas HOSSEINI Department of Civil Engineering Science and Research BranchIslamic Azad UniversityTehranIran

Modeling and prediction of bed loads is an important but difficult issue in river *** introduced empirical equations due to restricted applicability even in similar conditions provide different accuracies with each other and measured *** this paper,three different artificial neural networks(ANNs)including multilayer percepterons,radial based function(RBF),and generalized feed forward neural network using five dominant parameters of bed load transport formulas for the Main Fork Red River in Idaho-USA were *** optimum models were found through 102 data sets of flow discharge,flow velocity,water surface slopes,flow depth,and mean grain *** deficiency of empirical equations for this river by conducted comparison between measured and predicted values was approved where the ANN models presented more consistence and closer estimation to observed *** coefficient of determination between measured and predicted values for empirical equations varied from 0.10 to 0.21 against the 0.93 to 0.98 in ANN *** accuracy performance of all models was evaluated and interpreted using different statistical error criteria,analytical graphs and confusion *** the ANN models predicted compatible outputs but the RBF with 79%correct classification rate corresponding to 0.191 nctwork error was outperform than others.

关键词： bed load prediction artificial neural network modeling empirical equations

Simultaneous removal of copper and zinc ions by low cost natural snail shell/hydroxyapatite/chitosan composite

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Chinese Journal of Chemical Engineering 2021年第5期34卷 221-230页

作者： abbas Bambaeero Reza Bazargan-Lari Department of Materials Science&Engineering Marvdasht BranchIslamic Azad UniversityMarvdashtIran

In this work,the snail shell/hydroxyapatite/chitosan composite was prepared as *** adsorption potential of the composite was studied for simultaneous sorption behavior of Zn(Ⅱ)and Cu(Ⅱ)ions in a batch *** and hydroxyapatite(HAP)were extracted from shrimp shell and bone ash,respectively,so this is a low cost natural *** prepare the composite,chitosan was dissolved in acetic acid,then HAP and snail shell powders were added to the chitosan *** morphology and characterization of the composite was studied by SEM and EDX *** adsorption was used to measure the amount of the *** parameters were optimized with Design Expert Software and five parameters such as the concentration of ions,pH,adsorbent amount and contact time were studied at room *** value for the parameters of Zn(Ⅱ)and Cu(Ⅱ)concentrations,pH,adsorbent dose,and contact time were 3.01 mg·L^(-1),5.5,0.02 g and 95 min,*** adsorption isotherms for Zn(Ⅱ)and Cu(Ⅱ)showed Langmuir and Tempkin,*** and equilibrium studies showed the experimental data of Zn(Ⅱ)and Cu(Ⅱ)ions were best described by the pseudo-second-order *** on thermodynamic show the adsorption process were physical and spontaneous.

关键词： Hydroxyapatite Chitosan Composite Adsorbent

Effects of rotational components of earthquake on seismic response of arch concrete dams

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Earthquake Engineering and Engineering Vibration 2020年第2期19卷 349-362页

作者： Amir Javad Moradloo abbas Naiji Department of Civil Engineering School of EngineeringUniversity of ZanjanZanjan 38791-45371Iran

The present study deals with dynamic analysis of arch concrete dams,taking rotational components of earthquakes into account.A modified methodology was used to evaluate the rotational components of the *** translational components of the earthquake have been used in to obtain the rotational components of the earthquake,based on the intersecting isotropic elastic wave *** rotational components of Taft,Tabas and San-Fernando earthquakes are evaluated based on the translational components of the earthquakes and considering frequency dependencies of incident angle and wave ***,dynamic analyses of Morrow Point Dam are presented to evaluate the effects of combined translational and rotational components on the seismic response of the *** conditions of reservoirs,including full and empty state,are considered in the ***–structure interaction was completely taken into *** was realized that incorporating rotational components increased the maximum compressive and tensile stresses in both empty and full reservoir *** of maximum tensile stresses is very sensitive to the rotational components of the ***,it can be concluded that the segregated effect of the rocking component on the response of concrete dams is more effective than the sole effect of the torsional component.

关键词： rotational components earthquake arch concrete dam seismic analysis fluid-structure interaction

Optimization of electrochemically synthesized Cu3(BTC)2 by Taguchi method for CO2/N2 separation and data validation through artificial neural network modeling

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Frontiers of Chemical Science and Engineering 2020年第2期14卷 233-247页

作者： Kasra Pirzadeh Ali asghar Ghoreyshi Mostafa Rahimnejad Maedeh Mohammadi Chemical Engineering Department Babol Noshirvani University of TechnologyBabolIran

Cu(BTC),a common type of metal organic framework(MOF),was synthesized through electrochemical route for CO capture and its separation from *** method was employed for optimization of key parameters affecting the synthesis of Cu(BTC).The results indicated that the optimum synthesis conditions with the highest CO selectivity can be obtained using 1 g of ligand,applied voltage of 25 V,synthesis time of 2 h,and electrode length of 3 *** single gas sorption capacity of the synthetized microstructure Cu(BTC)for CO(at 298 K and 1 bar)was a considerable value of 4.40 mmol·*** isosteric heat of adsorption of both gases was calculated by inserting temperature-dependent form of Langmuir isotherm model in the Clausius-Clapeyron *** adsorption of CO/N binary mixture with a concentration ratio of 15/85 vol-%was also studied experimentally and the result was in a good agreement with the predicted value of IAST ***,Cu(BTC)showed no considerable loss in CO adsorption after six sequential *** addition,artificial neural networks(ANNs)were also applied to predict the separation behavior of CO/N mixture by MOFs and the results revealed that ANNs could serve as an appropriate tool to predict the adsorptive selectivity of the binary gas mixture in the absence of experimental data.

关键词： Cu3(BTC)2 electrochemical synthesis CO2 adsorption Taguchi optimization ANN modeling

Dispersive soliton solutions for shallow water wave system and modified Benjamin-Bona-Mahony equations via applications of mathematical methods

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Journal of Ocean Engineering and Science 2021年第1期6卷 85-98页

作者： asghar Ali Aly R.Seadawy Mathematics Department University of EducationLahorePakistan Mathematics Department Faculty of ScienceTaibah UniversityAl-Madinah Al-MunawarahSaudi Arabia

We have utilized three novel methods,called generalized direct algebraic,modified F-expansion and improved simple equation methods to construct traveling wave solutions of the system of shallow water wave equations and modified Benjamin-Bona-Mahony *** substituting particular values of the parameters,different solitary wave solutions are derived from the exact traveling wave *** is shown that these employed methods are more powerful tools for nonlinear wave equations.

关键词： System of shallow water wave equations Modified Benjamin-Bona-Mahony equation Generalized direct algebraic method Improved simple equation method Modified F-expansion method Traveling wave solutions Solitary wave solutions