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Earthquake Engineering and Engineering Vibration 2020年第2期19卷 435-449页

作者： Ghasemi Jouneghani abbas Haghollahi Department of Civil Engineering Shahid Rajaee Teacher Training UniversityTehranIran

Incremental dynamic analysis and nonlinear static pushover analysis are carried out on a performance-based design to determine the seismic demands and capacities of an elliptic braced moment resisting frame(ELBRF).The objective is to assess ductility,overstrength and response modification factors in a modern steel-braced structural system based on incremental dynamic *** integrated system is connected to a beam and column with an appropriate length while providing enough architectural space to allow for an opening without having the common problems associated with architectural spaces in braced *** different classes of buildings are considered on soil type *** dynamic analysis,nonlinear static pushover analysis and incremental nonlinear dynamic analysis related to 12 records from past earthquakes are carried out using OpenSees *** factors of ductility,overstrength and response modification are calculated for this *** values of 9.5 and 6.5 are found and suggested only for the response modification factor for ELBRF systems in allowable stress and ultimate limit state methods,*** fragility curves are plotted for the first time for this type of bracing,which contributes to the assessment of building seismic damage.

关键词： elliptic brace response modification factor overstrength factor ductility factor incremental dynamic analysis,fragility curve

Macro- and micromechanical evaluation of cyclic simple shear test by discrete element method

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Particuology 2017年第2期15卷 129-139页

作者： Mozhgan Asadzadeh abbas Soroush Department of Civil and Environmental Engineering Amirkabir University of Technology Tehran Iran

Direct simple shear tests are considered to be simple laboratory tests that are capable of imposing a cyclic loading that is analogous to that induced by earthquakes. A realistic evaluation of the test results demands a profound micromechanical investigation of specimens. Three-dimensional discrete element method models of a stacked-ring simple shear test were constructed, in which monotonic and cyclic loadings were applied under constant-volume conditions, and good agreement between the monotonic and cyclic macromechanical behaviors was noted. Micromechanical properties of specimens that were subjected to a cyclic loading are discussed in terms of lateral and intermediate principal stress development, fabric anisotropy, and principal stress rotation. The stress and strain states inside the specimen were investigated and it was shown that despite the uniform stress distribution inside the specimen, the volumetric strain distributes non-uniformly during loading and the non-uniformity grows with cycling, which leads to localized zones of dilative and contractive behavior.

关键词： Discrete element method Direct shear test Simple shear test Cyclic loading

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

Use of probabilistic and deterministic measures to identify unfavorable earthquake records

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第5期10卷 619-634页

作者： abbas MOUSTAFA Izuru TAKEWAKI Department of Urban and Environmental Engineering Graduate School of Engineering Kyoto UniversityNishikyo-ku 615-8540 Japan Department of Civil Engineering School of Engineering Minia UniversityMinia 61111 Egypt

This study introduces measures to identify resonant (concentration of energy in a single or a few frequencies) or unfavorable earthquake ground motions. Probabilistic measures based on the entropy rate and the geometric properties of the power spectral density function (PSDF) of the ground acceleration are developed first. Subsequently, deterministic measures for the frequency content of the ground acceleration are also developed. These measures are then used for identifying resonance and criticality in stochastic earthquake models and 110 acceleration records measured at rock, stiff, medium and soft soil sites. The unfavorable earthquake record for a given structure is defined as the record having a narrow frequency content and dominant frequency close to the structure fundamental natural frequency. Accordingly, the measures developed in this study may provide a basis for selecting records that are capable of producing the highest structural response. Numerical verifications are provided on damage caused to structures by identified resonant records.

关键词： Entropy rate Dispersion index Power spectral density function (PSDF) Frequency content Unfavorable groundmotion Resonant acceleration Critical accelerogram Energy Damage index

Neuroprotective potential of traditional Ayurvedic Kadha:age-related neurological disorders:a comprehensive literature review

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Traditional Medicine Research 2024年第9期9卷 51-77页

作者： Sarvin Sadreddini Mohammad Javad Emami Kazemabad Sogand Sheikholeslami Kosar Chitzan-Zadeh Mohammad Taha Kouchaki Midia Rashidi Amir abbas Ghayerin Shahin Sabaghi Ghazal Tavakoli Sepehr Nanbakhsh Tina Mansourian Arefeh Tabashiri Fariba Arbab Mojeni Mohammed Namiq Amin Zahra Taheri Seyed Esmaeil Sedighi Taraneh Tarkashvand Parham Amirazodi Mobina Fathi Shirin Yaghoobpoor Niloofar Deravi School of Medicine Tabriz University of Medical SciencesTabriz ***Iran School of Medicine Qom University of Medical SciencesQom ***Iran School of Medicine Hamadan University of Medical SciencesHamadan ***Iran School of Medicine Ahvaz Jundishapur University of Medical SciencesAhvaz ***Iran Faculty of Medicine Tabriz University of Medical SciencesTabriz ***Iran School of Medicine Iran University of Medical SciencesTehran ***Iran School of Medicine Shahid Beheshti University of Medical SciencesTehran ***Iran School of Medicine Mazandaran University of Medical SciencesSari ***Iran School of Medicine Kermanshah University of Medical SciencesKermanshah ***Iran Faculty of Pharmacy Pharmaceutical Sciences BranchIslamic Azad UniversityTehran ***Iran Department of Biology Faculty of SciencePayamNoor UniversityTehran ***Iran Faculty of Medicine Islamic Azad University of Medical ScienceTehran 193951495Iran International Campus Shahid Sadoughi University of Medical SciencesYazd ***Iran

Despite modern medicine’s advancements,age-related neurological diseases like Alzheimer’s disease and Parkinson’s disease remain challenging due to high costs,side effects,and limited ***,a traditional Indian medicine system,offers Kadha tea as a potential herbal *** review explores Kadha’s components(basil(Ocimum basilicum L.),black pepper(Piper nigrum L.),Cinnamon(Cinnamomum verum ***),ginger(Zingiber officinale Roscoe),and raisin(Vitis vinifera L.))and their interaction with various neurological *** suggest Kadha exhibits anti-inflammatory,antioxidant,and antiviral properties,potentially impacting Alzheimer’s disease,Parkinson’s disease,neurotoxicity,neuroinflammation,and brain *** focusing on specific disease mechanisms and Kadha’s intergrade effects,this review aims to elucidate its potential role in managing age-related neurological disorders.

关键词： Ayurveda Kadha neuroprotective neurological disorders traditional medicine

Enhanced catalytic complete oxidation of 1,2-dichloroethane over mesoporous transition metal-doped γ-Al_2O_3

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Journal of Environmental Sciences 2015年第3期27卷 199-209页

作者： abbas Khaleel Muhammad Nawaz Department of Chemistry United Arab Emirates University

High-surface-area mesoprous powders of γ-Al2O3 doped with Cu^2＋, Cr^3＋, and V^3＋ ions were prepared uia a modified sol-gel method and were investigated as catalysts for the oxidation of chlorinated organic compounds. The composites retained high surface areas and pore volumes comparable with those of undoped γ-Al2O3 and the presence of the transition metal ions enhanced their surface acidic properties. The catalytic activity of the prepared catalysts in the oxidation of 1,2-dichloroethane （DCE） was studied in the temperature range of 250-400℃. The catalytic activity and product selectivity were strongly dependent on the presence and the type of dopant ion. While Cu^2＋- and Cr^3＋-containing catalysts showed 100% conversion at 300℃ and 350℃, V3＋-containing catalyst showed considerably lower conversion. Furthermore, while the major products of the reactions over γ-alumina were vinyl chloride （C2H3Cl） and hydrogen chloride （HCl） at all temperatures, Cu- and Cr-doped catalysts showed siguiticantly stronger capability for deep oxidation to CO2.

关键词： Chlorinated organic compounds Catalytic oxidation Sol-gel method Mixed metal oxides

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

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