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Journal of Natural Gas Chemistry 2008年第2期17卷 135-141页

作者： M.Peer M.Mahdyarfar t.mohammadi Research Center for Membrane Processes Department of Chemical EngineeringIran University of Science and TechnologyNarmakTehranlran Gas Division Research Institute of Petroleum IndustryTehranIran

In recent times, membranes have found wide applications in gas separation processes. As most of the industrial membrane separation units use hollow fiber modules, having a proper model for simulating this type of membrane module is very useful in achieving guidelines for design and characterization of membrane separation units. In this study, a model based on Coker, Freeman, and Fleming＇s study was used for estimating the required membrane area. this model could simulate a multicomponent gas mixture separation by solving the governing differential mass balance equations with numerical methods. Results of the model were validated using some binary and multicomponent experimental data from the literature. Also, the artificial neural network （ANN） technique was applied to predict membrane gas separation behavior and the results of the ANN simulation were compared with the simulation results of the model and the experimental data. Good consistency between these results shows that ANN method can be successfully used for prediction of the separation behavior after suitable training of the network

关键词： hollow fiber membrane gas separation mathematical modeling artificial neural network

KAI（SO4）2-12H2O （Alum） Catalyzed One-Pot three-Component Synthesis of 2-Alkyl and 2-Aryl-4（3H）-quinazolinone under Microwave Irradiation and Solvent Free Conditions

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Chinese Journal of Chemistry 2011年第9期29卷 1982-1984页

作者： mohammadi, Ali A. Sadat Hossini, S. S.t Department of Chemistry Sabzevar Branch Islamic Azad University Sabzevar Iran University of Applied Science and technology Tehran P.. O. Box 14155-1644 Tehran Iran

twenty 2,3-disubstituted-4（3H）-quinazolinones were synthesed by one-pot three-component method with isa- toic anhydride, orthoesters and amines as raw materials in the presence of KAI（SO4）2·12H2O （Alum） under micro- wave irradiation and solvent-free conditions. 6-Bromo-2-propyl-3-p-tolylquinazolin-4（3H）-one （4m）, 6-bromo-2- methyl-3-phenethylquinazolin-4（3H）-one （4n） and 6-bromo-2-ethyl-3-phenethylquinazolin-4（3H）-one （40） were characterized by IR, 1H NMR, 13C NMR and elemental analysis.

关键词： isatoic anhydride orthoesters ammonium acetate 4(3H)-quinazolinone multi component micro-wave-assisted reactions

Kinetics of(tBAF+CO2)semi-clathrate hydrate formation in the presence and absence of SDS

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Petroleum Science 2018年第2期15卷 375-384页

作者： A.mohammadi M.Pakzad A.H.mohammadi A.Jahangiri Department of Chemical Engineering University of BojnordBojnordIran Department of Chemical Engineering Omidiyeh BranchIslamic Azad UniversityOmidiyehIran Institut de Recherche en Genie Chimique et Petrolier(IRGCP) Paris CedexFrance thermodynamics Research Unit School of EngineeringUniversity of KwaZulu-NatalHoward College CampusKing George V AvenueDurban 4041South Africa Faculty of Engineering Shahrekord UniversityShahrekordIran

In this communication, the impacts of adding SDS （sodium dodecyl sulfate）, tBAF （tetra-n-butylammonlum tluorloe） ano the mixture of SDS ＋ tBAF on the main kinetic parameters of CO2 hydrate formation （induction time, the quantity and rate of gas uptake, and storage capacity） were investigated. the tests were performed under stirring conditions at t = 5 ℃ and P = 3.8 MPa in a 169 cm3 batch reactor. the results show that adding SDS with a concentration of 400 ppm, tBAF with a concentration of l-5 wt%, and the mixture of SDS ＋ tBAF, would increase the storage capacity of CO2 hydrate and the quantity of gas uptake, and decrease the induction time of hydrate formation process. the addition of 5 wt% of tBAF and 400 ppm of SDS would increase the CO2 hydrate storage capacity by 86.1% and 81.6%, respectively, compared to pure water. Investigation of the impact of SDS, tBAF and their mixture on the rate of gas uptake indicates that the mixture of SDS ＋ tBAF does not have a significant effect on the rate of gas uptake during hydrate formation process.

关键词： Semi-clathrate hydrate Gas hydrate Kinetics CO2 SDS tBAF

Effect of exhaust gas recirculation and intake pre-heating on performance and emission characteristics of dual fuel engines at part loads

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Journal of Central South University 2012年第5期19卷 1346-1352页

作者： A.Paykani R.Khoshbakhti Saray M.t.Shervani-tabar A.mohammadi-Kousha Department of Automotive Engineering Iran University of Science and TechnologyNarmakTehran ***Iran Department of Mechanical Engineering Sahand University of TechnologySahand New CityTabrizIran Department of Mechanical Engineering University of TabrizTabrizIran

Achieving simultaneous reduction of NOx,CO and unburned hydrocarbon(UHC) emissions without compromising engine performance at part loads is the current focus of dual fuel engine *** present work focuses on an experimental investigation conducted on a dual fuel(diesel-natural gas) engine to examine the simultaneous effect of inlet air pre-heating and exhaust gas recirculation(EGR) ratio on performance and emission characteristics at part *** use of EGR at high levels seems to be unable to improve the engine performance at part ***,it is shown that EGR combined with pre-heating of inlet air can slightly increase thermal efficiency,resulting in reduced levels of both unburned hydrocarbon and NOx *** and UHC emissions are reduced by 24% and 31%,respectively,the NOx emissions decrease by 21% because of the lower combustion temperature due to the much inert gas brought by EGR and decreased oxygen concentration in the cylinder.

关键词： dual fuel engine exhaust gas recirculation (EGR) emission performance venturi EGR system

Innovative configuration of vertical slot fishway to enhance fish swimming conditions

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Journal of Hydrodynamics 2022年第5期34卷 917-933页

作者： Mohammad Ahmadi Alban Kuriqi Hossein Mohammad Nezhad Amir Ghaderi Mirali mohammadi Department of Civil Engineering Faculty of EngineeringShabestar BranchIslamic Azad UniversityShabestarIran CERIS Instituto Superior TécnicoUniversidade de LisboaLisbonPortugal Civil Engineering Department University for Business and TechnologyPristinaKosovo Department of Civil Engineering Faculty of EngineeringUrmia UniversityUrmiaIran Department of Civil Engineering Faculty of EngineeringUniversity of ZanjanZanjanIran

A vertical slot fishway(VSF)is among the most effective and commonly used fishway structures to enable fish to pass through artificial barriers such as dams and weirs in the ***,such structures need further improvements in providing better swimming conditions for fish inside the pool and enhancing attraction at the ***,the main objective of this study was to investigate the influence of slope and whether integrating some cylinder structures inside the fishway could enhance further attraction and provide better swimming conditions for *** study consists of several numerical simulations,first considering the fishway without cylinder elements while testing three different slopes under two different ***,the same numerical simulations were conducted,considering cylinder elements of different diameters and arrangements inside the *** numerical model was validated by comparing computed velocities with those measured experimentally from the *** results show that the maximum velocity and turbulent kinetic energy(tKE)in the main jet increase as the discharge increases on the same *** flow velocity and tKE decrease in the areas inside the pool and between the two *** cylinder elements inside the fishway reduces the principal flow’s maximum ***,inside the pool,low-velocity regions were expanding.A comparison between the design with a cylinder and the simple VSF indicates that the presence of a cylinder reduced the maximum velocities for the smallest and highest slopes by 6.21%and 9.86%on average,***,in terms of tKE,cylinders inside the fishway could provide better performance than simple VSF,mainly for low-flow ***,this study’s solution-oriented findings provide insights that could help design cost-effective fishways by improving particularly fish attraction to the fishway.

关键词： Ecohydraulic energy dissipation fish-pass fishway turbulent kinetic energy(tKE)

Evaluation of the effects of Alkyl Phenolic compounds on kinetic coefficients and biomass activity in MBBR by means of respirometric techniques

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Chinese Journal of Chemical Engineering 2018年第4期26卷 822-829页

作者： Bijan Bina Farzaneh mohammadi Mohammad Mehdi Amin Hamid Reza Pourzamani Zeynab Yavari Environment Research Center Research Institute for Primordial Prevention of Non-communicable Disease Isfahan University of Medical Sciences Department of Environmental Health Engineering School of Health Isfahan University of Medical Sciences Student Research Committee Isfahan University of Medical Sciences

the presence of Alkyl Phenols(APs) in aquatic systems is considered as one of the environmental concerns in recent decades which are generally used as surfactants. APs are endocrine disruptors and estrogen-mimicking,causing harmful effects such as feminization and carcinogenesis on aquatic environment and human *** most commercially important APs are 4-Nonyl Phenol(4-NP) and 4-tert-OctylP henol(4-t-OP). Moving bed biofilm reactor(MBBR), which combined attached and suspended growth advantages, is an advanced biological treatment process for municipal and industrial wastewaters that has drawn considerable attention from many researchers to remove toxic pollutants from wastewater. the aim of this research was to evaluate Bacterial activities and kinetic coefficients in the presence of APs. this study was carried out using laboratory-scale MBBR fed with synthetic wastewater containing 4-NP and 4-t-OP. the reactor was operated at different loads of chemical oxygen demand(COD) and APs and different hydraulic retention time(HRt). the respirometric technique was applied to investigate the effect of APs on heterotrophic and autotrophic activity and kinetic coefficients in biomass obtained from MBBR. Respirometric technique demonstrates a reliable tool in order to assess the biofilm kinetic coefficients and biomass viability to insert in the mathematical models. the calculated kinetic parameters were in the range of conventional and extended aeration activated sludge processes. the results demonstrate that APs have significant inhibitory effects on activity and growth rate of heterotrophic and autotrophic bacteria, heterotrophs have been less affected by the presence of 4-NP and 4-t-OP, and these compounds had greater inhibitory effects on autotrophic bacteria.

关键词： Alkyl Phenols Autotrophs Heterotrophs Kinetic coefficients MBBR Respirometric techniques

Determination of 4-nonylphenol and 4-tert-octylphenol compounds in various types of wastewater and their removal rates in different treatment processes in nine wastewater treatment plants of Iran

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Chinese Journal of Chemical Engineering 2018年第1期26卷 183-190页

作者： Bijan Bina Farzaneh mohammadi Mohammad Mehdi Amin Hamid Reza Pourzamani Zeynab Yavari Environment Research Center School of HealthIsfahan University of Medical Sciences Student Research Center School of HealthIsfahan University of Medical Sciences

Alkylphenols(APs), considered as xenoestrogenic compounds, mainly exist as 4-nonylphenol(4-NP) and 4-tertoctylphenol(4-t-OP) in environments. the high stability and accumulation of APs in aquatic systems have caused endocrine disruption. In this study we measured APs in the wastewater influent and effluent samples, from the urban, rural, livestock, commercial and hospital wastewater treatment plants(WWtPs) in Iran. Dispersive liquid–liquid microextraction(DLLME) combined with gas chromatography–mass spectrometry(GC–MS) was used for the extraction and determination of 4-NP and 4-t-OP. In these treatment plants, various processes such as activated sludge, aerated lagoon, moving bed biofilm reactor and activated sludge along with wetland were applied. the highest concentration of 4-NP and 4-t-OP was observed in commercial and livestock sewages. the activated sludge along with wetland and then the MBBR process showed the highest removal rates of pollutants. the rates of biodegradability and accumulation in sludge were determined and also the specific adsorption coefficient Kdand the organic carbon–water partition coefficient kOCof the sludge for APs were calculated.

关键词： Alkylphenols DLLME Full scale WWtP Biodegradation Adsorption

Effects of heat treatment on the corrosion behavior and mechanical properties of biodegradable Mg alloys

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Journal of Magnesium and Alloys 2022年第7期10卷 1737-1785页

作者： Meysam mohammadi Zerankeshi Reza Alizadeh Ehsan Gerashi Mohammad Asadollahi terence G.Langdon Department of Materials Science and Engineering Sharif University of TechnologyTehranIran Materials Research Group Department of Mechanical EngineeringUniversity of SouthamptonSouthampton SO171BJUnited Kingdom

Biodegradable magnesium(Mg)alloys exhibit great potential for use as temporary structures in tissue engineering *** degradable implants require no secondary surgery for their *** addition,their comparable mechanical properties with the human bone,together with excellent biocompatibility,make them a suitable candidate for fracture ***,some challenges *** degradation of the Mg-based alloys in physiological environments leads to a loss of the mechanical support that is needed for complete tissue healing and also to the accumulation of hydrogen gas bubbles at the interface of the implant and *** different methods used to improve the performance of the biodegradable Mg alloys to address these challenges,it appears that heat treatment is the most effective way to modify the microstructure and thus the corrosion behavior and mechanical properties without changing the composition or shape of the alloys.A desirable combination of corrosion and mechanical properties can be obtained through a precise control of the heat treatment *** this report,the effects of different heat treatments(t4 and t6)on the microstructure,corrosion behavior,and mechanical properties of some of the most important heat-treatable biodegradable Mg alloys(Mg-Zn,Mg-Gd,Mg-Y,Mg-Nd,Mg-Al and Mg-Ag)are examined as well as new perspectives to enhance their clinical implementation.

关键词： Biodegradable implants Corrosion rate Heat treatment Mechanical properties Mg alloys

Country-scale spatio-temporal monitoring of soil erosion in Iran using the G2 model

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International Journal of Digital Earth 2021年第8期14卷 1019-1039页

作者： Shahin mohammadi Fatemeh Balouei Khadijeh Haji Abdulvahed Khaledi Darvishan Christos G.Karydas Department of Remote Sensing and GIS Faculty of Earth SciencesShahid Chamran University of AhvazAhvazIran Department of Range and Watershed Management Faculty of Natural ResourcesIsfahan University of TechnologyIsfahanIran Department of Watershed Management Engineering Faculty of Natural ResourcesTarbiat Modares UniversityNoorIran dRemote Sensing Engineer EpanomiGreece

the aim of this study was the spatial and temporal monitoring of soil erosion patterns in *** G2 model was used,as an appropriate tool to provide the required month-time step country-wide soil loss maps and statistical *** input parameters were derived with field surveys and remote sensing imagery(MODIS,SRtM,SPOt,and Sentinel-2 scenes).An innovation for G2 was the consideration of the snow cover effect on the rainfall *** was also the first time G2 was used to map such a big country like Iran on a country *** mean annual soil erosion in Iran was found to be 16.5 t ha−1,which is equal to about 2.7 billion tons of soil *** spatial terms,the highest soil loss values were found in the north,west and southwest part of Iran,in the steep slopes in Alborz and Zagros *** temporal terms,the highest and lowest monthly erosion values of 3.2 and 0.09 t ha−1 correspond to January and July,respectively.

关键词： Digital earth Land degradation Sediment yield Sentinel-2 Snow cover effect

Recombinant hybrid protein, Shiga toxin and granulocyte macrophage colony stimulating factor effectively induce apoptosis of colon cancer cells

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World Journal of Gastroenterology 2006年第15期12卷 2341-2344页

作者： Mehryar Habibi Roudkenar Saeid Bouzari Yoshikazu Kuwahara Amaneh mohammadi Roushandeh Mana Oloomi Manabu Fukumoto Molecular Biology Unit Pasteur Institute of Iran Pasteur AveTehran 13164Iran Department of Pathology Institute of Development Aging and CancerTohoku UniversitySeiryo-cho 4-1Aoba-wardSendai-cityMiyagi-prefecture980-8575Japan Department of Anatomy Medicine Faculty Medical University of TehranTehran 13164Iran

AIM： to investigate the selective cytotoxic effect of constructed hybrid protein on cells expressing granulocyte macrophage colony stimulating factor （GM-CSF） receptor. MEtHODS： HepG2 （human hepatoma） and LS174t （colon carcinoma） were used in this study. the fused gene was induced with 0.02% of arabinose for 4 h and the expressed protein was detected by Western blotting. the chimeric protein expressed in E..coli was checked for its cytotoxic activity on these cells and apoptosis was measured by comet assay and nudear staining. RESULtS： the chimeric protein was found to be cytotoxic to the colon cancer cell line expressing GM-CSFRs, but not to HepG2 lacking these receptors. Maximum activity was observed at the concentration of 40 ng/mL after 24 h incubation. the IC50 was 20 ± 3.5 ng/mL. CONCLUSION： Selective cytotoxic effect of the hybrid protein on the colon cancer cell line expressing GMCSF receptors （GM-CSFRs） receptor and apoptosis can be observed in this cell line. the hybrid protein can be considered as a therapeutic agent.

关键词： Shiga toxin hGM-CSF Apoptosis Colon canoer Cell lines