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Chinese Physics B 2016年第9期25卷 381-387页

作者： Ali Raoof Toosi Hamid reza Shamlouei Asghar mohammadi Hesari Lorestan University Chemistry Department

The effect of alkali metal superoxides M_3O（M = Li,Na,K） on the electronic and optical properties of a Be_（12）O_（12） nanocage was studied by density functional theory（DFT） and time-dependent density functional theory（TD-DFT）.The energy gaps（Eg） of all configurations were ***,the adsorption of alkali metal superoxides on the Be_（12）O_（12） nanocage causes a decrease of *** dipole moment μ,polarizability α,and static first hyperpolarizability β were calculated and it was shown that the adsorption of alkali metal superoxides on Be_（12）O_（12） increases its *** was found that the absorption of M_3 O on Be_（12）O_（12） nanocluster improves its nonlinear optical *** highest first hyperpolarizability（β≈ 214000 a.u.） is obtained in the K_3O–Be_（12）O_（12）*** TD-DFT calculations were performed to investigate the origin of the first hyperpolarizabilities and it was shown that a higher first hyperpolarizability belongs to the structure that has a lower transition energy.

关键词： Be_(12)O_(12) alkali metal superoxides hyperpolarizability DFT calculation

Effect of TiO2 loading on the morphology and CO2/CH4 separation performance of PEBAX-based membranes

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Frontiers of Chemical Science and Engineering 2019年第3期13卷 517-530页

作者： Navid Azizi Mojgan Isanejad Toraj mohammadi reza M. Behbahani Research and Technology Center of Membrane Processes Chemical Engineering DepartmentIran University o f Science and Technology (IUST)NarmakTehranIran Gas Engineering Department Petroleum University of TechnologyAhwazIran

Membranes have attracted much attention as economical methods for industrial chemical processes. The effects of the titanium dioxide nanoparticle load on the morphology and CO2/CH4 separation performance of poly (ether-block-amide)(PEBAX-1657) mixed matrix membranes (MMMs) were investigated from pressures of 3-12 bar and temperatures of 30℃-60℃. The PEBAX membranes were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, thermal gravimetric analysis, atomic force microscopy and tensile strength analysis. The incorporation of TiO2 nanoparticles into the polymeric MMMs improved the CO2/CH4 gas separation performance (both the permeability and selectivity) of the membranes. The CO2 permeability and ideal CO2/CH4 selectivity values of the nanocomposite membrane loaded with 8 wt-% TiO2 were 172.32 Barrer and 24.79, respectively whereas those of the neat membrane were 129.87 Barrer and 21.39, respectively.

关键词： mixed matrix membrane TiO2 nanoparticles PEBAX-1657 C02/CH4 separation

1-Methylimidazole-catalyzed reaction between tosylmethyl isocyanide and dialkyl acetylenedicarboxylates:An efficient synthesis of functionalized pyrroles

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Chinese Chemical Letters 2011年第3期22卷 314-317页

作者： Mehdi Adib Bagher mohammadi Ehsan Sheikhi Hamid reza Bijanzadeh School of Chemistry University College of ScienceUniversity of TehranPO Box 14155-6455TehranIran Department of Chemistry Tarbiat Modarres UniversityPO Box 14115-175TehranIran

An efficient 1-methylimidazole-catalyzed synthesis of dialkyl 2-[（4-methylphenyl）sulfonyl]-1H-pyrrole-3,4-dicarboxylates is *** reactive 1：1 zwitterionic intermediate formed by the addition of 1-methylimidazole to dialkyl acetylenedicarboxylates is trapped by tosylmethyl isocyanide（TOSMIC） to afford the title compounds in excellent yields.

关键词： 1-Methylimidazole Tosylmethyl isocyanide Acetylenic esters Pyrrole synthesis

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

NEW APPROACH TO EMULATE SEU FAULTS ON SRAM BASED FPGAS

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Journal of Electronics(China) 2014年第1期31卷 68-77页

作者： reza Omidi Gosheblagh Karim mohammadi Department of Electrical Engineering Iran University of Science and Technology (IUST)

Field Programmable Gate Arrays(FPGAs)offer high capability in implementing of complex systems,and currently are an attractive solution for space system ***,FPGAs are susceptible to radiation induced Single-Event Upsets(SEUs).To insure reliable operation of FPGA based systems in a harsh radiation environment,various SEU mitigation techniques have been *** this paper we propose a system based on dynamic partial reconfiguration capability of the modern devices to evaluate the SEU fault effect in *** proposed approach combines the fault injection controller with the host FPGA,and therefore the hardware complexity is *** of the SEU injection and evaluation requirements are performed by a soft-core which realized inside the host *** results on some standard benchmark circuits reveal that the proposed system is able to speed up the fault injection campaign 50 times in compared to conventional method.

关键词： Field Programmable Gate Arrays(FPGAs) Single-Event Upset(SEU) fault injection Soft-core Space radiation effects

Highly efficient bis(aminotropone) Ti catalyst for ethylene polymerization

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Chinese Chemical Letters 2011年第2期22卷 213-216页

作者： reza Sandaroos Saman Damavandi Ali Nazif Maraym Goharjoo Ali mohammadi Department of Chemistry School of SciencesFerdowsi University of MashhadP.O.Box 91775MashhadIran Department of Chemistry Islamic Azad University of SarvestanSarvestanIran

Synthesis and structure of Ti complex having a pair of chelating aminotropone[O-N]ligand have been *** of density functional theory（DFT） studies suggest that bis（aminotropone） Ti complex,when activated with methylaluminoxane （MAO）,have high potential for the polymerization of olefinic *** theoretical studies also show that the active species derived from bis（aminotropone） Ti catalyst normally possess higher electrophilicity nature compared with those produced using bis（phenoxyimine） Ti complexes（Ti-FI catalysts） which are known as high performance olefin polymerization catalysts. Bis（aminotropone） Ti catalyst generates a catalytically active species that has higher electrophilicity than a Ti-FI catalysts.

关键词： Aminotropone Ethylene polymerization DFT studies PI catalysts

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

Aminobenzenesulfonamide functionalized SBA-15 nanoporous molecular sieve: A new and promising adsorbent for preconcentration of lead and copper ions

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Journal of Environmental Sciences 2012年第7期24卷 1347-1354页

作者： Leila Hajiaghababaei Babak Ghasemi Alireza Badiei Hassan Goldooz Mohammad reza Ganjali Ghodsi mohammadi Ziarani Department of Chemistry Islamic Azad UniversityShahre Rey Branch School of Chemistry College of ScienceUniversity of Tehran Center of Excellence in Electrochemistry Faculty of ChemistryUniversity of Tehran Department of Chemistry Alzahra University

A rapid method for the extraction and monitoring of nanogram level of Pbz＋ and Cuz＋ ions using uniform silanized mesopor （SBA-15） functionalized with aminobenzenesulfonamide groups and flame atomic absorption spectrometry （FAAS） is presented. Aminobenzenesulfonamide functionalized SBA-15 was synthesized according to procedure in the literature and the presence of organic groups in the silica framework was demonstrated by FT-IR spectra. The functionalized product showed the BET surface area 110 mZ/g and pore diameter 5. l nm, based on adsorption-desorption of N2 at 77 K. The effect of several variables such as （amount of adsorbent, stirring time, pH and presence of other ions in the medium） has been studied. Lead and copper were completely extracted at pH greater than 3 after stirring for 10 min. The maximum capacity of the adsorbent was found to be 191.3 ＋ 1.4 and 155.0 ＋ 1.0 ~xg of lead and copper ions/mg functionalized SBA-15, respectively. The preconcentration factor of the method was found to be 200. The detection limit of the technique was 3.4 and 0.4 ng/mL for Pb2＋ and Cuz＋, respectively. The applications of this methodology for real samples were examined by various water type, black tea and pepper samples.

关键词： aminobenzenesulfonamide functionalized SBA-15 preconcentration Pb2+ and Cu2+ions

A dynamic method for experimental assessment of scale inhibitor efficiency in oil recovery process by water flooding

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Petroleum 2019年第3期5卷 303-314页

作者： Jaber Azizi Seyed reza Shadizadeh Abbas Khaksar Manshad Amir H.mohammadi Department of Petroleum Engineering Abadan Faculty of Petroleum EngineeringPetroleum University of Technology(PUT)Iran Institut de Recherche en Genie Chimique et Petrolier(IRGCP) France Discipline of Chemical Engineering School of EngineeringUniversity of KwaZulu-NatalHoward College Campus4041South Africa

Scale formation due to the mixing of injection water with formation water causes formation damage and reduction in petroleum *** using scale inhibitors,scale formation/scaling could be *** this work,static experiments were performed with rapid controlled precipitation tests,which were undertaken using three different scale inhibitors namely Falat scale inhibitor,Scahib 760 scale inhibitor and Scahib 780 scale *** show that parameters such as temperature and pH have significant effects on scale inhibitor *** this study,at pH of 7.8e9 it was found that an increase in pH can lead to a decrease in SI *** addition,acquired data shows that Falat scale inhibitor is more efficient at 45C but scale inhibitors(Scahib 760,780)have better efficiencies at 25*** tests were performed to find structure deformation and morphology of precipitation crystals,which indicated that scale inhibitor can have various effects on crystal's ***,dynamic tests were performed with coreflood equipment that indicated higher recovery by using the scale *** dynamic tests results show that the recovery factor in the presence of Scahib 760 scale inhibitor is about 58%and breakthrough time is 2099(sec).In the absence of scale inhibitor,the recovery factor is about 52%and breakthrough time is 2720(sec).

关键词： Scale inhibitor Formation damage Scaling index Static test Dynamic test SEM test