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A Green Route for the One-Pot Synthesis of 1,2-Disubstituted Benzimidazoles Using Iron（Ill） Phosphate under Solventless Conditions

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Chinese Journal of Chemistry 2012年第1期30卷 65-70页

作者： behbahani,F.k. Ziaei,Parisa Department of Chemistry Karaj BranchIslamic Azad UniversityKarajIran

1,2-Disubstituted benzimidazoles are selectively synthesized in high yields under extremely mild conditions via the condensation of o-phenylenediamine derivatives with aldehyde derivatives using catalytic amount of iron（Ⅲ） phosphate under solventfree conditions. The use of readily available iron（Ⅲ） phosphate as a reusable and recyelable catalyst makes this process quite simple, convenient, and environment-friendly.

关键词： 1,2-disubstituted benzimidazoles iron(Ill) phosphate solvent-free

Experimental study and a proposed new approach for thermodynamic modeling of wax precipitation in crude oil using a PC-SAFT model

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Petroleum Science 2016年第1期13卷 155-166页

作者： Taraneh Jafari behbahani Research Institute of Petroleum Industry (RIPI) P.O.Box 14665-1998 Tehran Iran

A powerful method is necessary for thermodynamic modeling of wax phase behavior in crude oils,such as the perturbed-chain statistical associating fluid theory（PC-SAFT）.In this work,a new approach based on the wax appearance temperature of crude oil was proposed to estimate PC-SAFT parameters in thermodynamic modeling of wax precipitation from crude *** proposed approach was verified using experimental data obtained in this work and also with those reported in the *** order to compare the performance of the PC-SAFT model with previous models,the wax precipitation experimental data were correlated using previous models such as the solid solution model and multi-solid phase *** results showed that the PC-SAFT model can correlate more accurately the wax precipitation experimental data of crude oil than the previous models,with an absolute average deviation less than 0.4 %.Also,a series of dynamic experiments were carried out to determine the rheological behavior of waxy crude oil in the absence and presence of a flow improver such as ethylene–vinyl acetate *** was found that the apparent viscosity of waxy crude oil decreased with increasing shear ***,the results showed that the performance of flow improver was dependent on its molecular weight.

关键词： crude deviation thermodynamic viscosity copolymer appearance rheological hydrocarbons verified powerful

Shear strength of clayey sand treated by nanoclay mixed with recycled polyester fiber

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Journal of Central South University 2022年第1期29卷 259-269页

作者： Mehrdad kHOLGHIFARD Babak AMINI behbahani Department of Civil Engineering Yasooj BranchIslamic Azad UniversityYasooj ***Iran

The main objective of this study is to investigate the effects of the nanoclay mixed with recycled polyester fiber on the mechanical behavior of soil as a new stabilizer *** meet this objective,a series of drained direct shear and compaction tests were performed on unreinforced and reinforced soil specimens with three different combinations of the fiber-soil ratios ranging between 0.1%and 0.5%,as well as three different combinations of nanoclay soil ratios ranging between 0.5%and 1.5%of the soil dry *** indicated that composition of the nanoclay recycled polyester fiber with the soil improved the friction angle(Φ)by 41%and cohesion(c)by 174%.The soil particles stick together through viscose gel produced by *** addition,the rough and wavy surface of the fibers creates a bond and friction between the soil particles and prevents the movement of soil particles,and as a result,the soil strength is increased.

关键词： soil treatment nanoclay recycled polyester fiber shear strength clayey sand

Synthesis of a PEBAX-1074/ZnO nanocomposite membrane with improved CO_2 separation performance

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Journal of Energy Chemistry 2017年第3期26卷 454-465页

作者： Navid Azizi Toraj Mohammadi Reza Mosayebi behbahani Research and Technology Center of Membrane Processes Chemical Engineering DepartmentIran University of Science and Technology (IUST) Gas Engineering Department Petroleum University of Technology

In this investigation, polymeric nanocomposite membranes（PNMs） were prepared via incorporating zinc oxide（ZnO） into poly（ether-block-amide）(PEBAX-1074) polymer matrix with different loadings. The neat membrane and nanocomposite membranes were prepared via solution casting and solution blending methods, respectively. The fabricated membranes were characterized by field emission scanning electron microscopy（FESEM） to survey cross-sectional morphologies and thermal gravimetric analysis（TGA）to study thermal stability. Fourier transform infrared（FT-IR） and X-ray diffraction（XRD） analyses were also employed to identify variations of the chemical bonds and crystal structure of the membranes, respectively. Permeation of pure gases, CO, CHand Nthrough the prepared neat and nanocomposite membranes was studied at pressures of 3–18 bar and temperature of 25 °C. The obtained results showed that the fabricated nanocomposite membranes exhibit better separation performance compared to the neat PEBAX membrane in terms of both permeability and selectivity. As an example, at temperature of 25 °C and pressure of 3 bar, COpermeability, ideal CO/CHand CO/Nselectivity values for the neat PEBAX membrane are 110.67 Barrer, 11.09 and 50.08, respectively, while those values are 152.27 Barrer,13.52 and 62.15 for PEBAX/ZnO nanocomposite membrane containing 8 wt% ZnO.

关键词： Nanocomposite membrane ZnO nanoparticles PEBAX-1074 CO2/CH4 separation

Energy spectrum of multi-radiation of X-rays in a low energy Mather-type plasma focus device

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Chinese Physics B 2014年第6期23卷 375-380页

作者： Farzin M.Aghamir Reza A.behbahani Department of Physics University of Tehran

The multi-radiation of X-rays was investigated with special attention to their energy spectrum in a Mather-type plasma focus device （operated with argon gas）. The analysis is based on the effect of anomalous resistances. To study the energy spectrum, a four-channel diode X-ray spectrometer was used along with a special set of filters. The filters were suitable for detection of medium range X-rays as well as hard X-rays with energy exceeding 30 keV. The results indicate that the anomalous resistivity effect during the post pinch phase may cause multi-radiation of X-rays with a total duration of 300 ± 50 ns. The significant contribution of Cu-kα was due to the medium range X-rays, nonetheless, hard X-rays with energies greater than 15 keV also participate in the process. The total emitted X-ray energy in the forms of Cu-k and Cu-k/3 was around 0.14 ± 0.02 （J/Sr） and 0.04 ±0.01 （J/Sr）, respectively. The total energy of the emitted hard X-ray （〉 15 keV） was around 0.12± 0.02 （J/Sr）.

关键词： Mather-type plasma focus device hard X-rays multi-radiation tube multiple voltage peaks,anomalous resistances

Numerical modeling of cavitation on spillway＇s flip bucket

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Frontiers of Structural and Civil Engineering 2016年第4期10卷 438-444页

作者： Abbas PARSAIE Sadegh DEHDAR-behbahani Amir Hamzeh HAGHIABI Department of water Engineering Lorestan University Khorramabad Iran Hydro Structures Shahid Chamran University Ahvaz Iran

Numerical modeling of hydraulic phenomenon by computational fluid dynamic （CFD） approaches is one of the main parts in the high cost hydraulic structure studies. In this paper, using Flow 3D as CFD commercial tool, the cavitation phenomenon was assessed along spillway＇s flip bucket of the Balaroud dam. Performance of numerical modeling was compared to the physical model, which was constructed to this purpose. During numerical modeling, it was found that RNG turbulence model is a suitable performance for modeling the cavitation. Physical modeling shows that minimum cavitation index is about 0.85 and minimum cavitation index based on Flow 3D results is about 0.665, which was related to the flood discharge with return period of 10000 years. The main difference between numerical and physical modeling is related to the head of velocity, which is considered in physical modeling. Results of numerical simulation show that occurrence of cavitation based on cavitation index equal to 0.25 is not possible along the spillway.

关键词： cavitation Index numerical simulation spillway's flip Bucket CFD Balaroud Dam physical modeling

Development of minimum tie line length method for determination of minimum miscible pressure in gas injection process

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Petroleum Research 2019年第2期4卷 173-180页

作者： Ehsan Zareie shirazani Taraneh Jafari behbahani Research Institute of Petroleum Industry(RIPI) TehranIran Islamic Azad University Central Tehran BranchTehranIran

Gas injection process is a very important technology in enhanced oil *** miscible pressure is one of the key parameters in gas injection *** experimental methods such as slim tube are used to measure *** methods are costly and time *** computational methods are used in order to achieve a cost-effective and reliable technique to evaluate *** this work,a new methodology has been proposed for determination of MMP using the minimum tie line length method.A real mixing cell model was developed to estimate the MMP,MME and key tie *** method is simple,robust,and faster than conventional one-dimensional simulation of slim *** new mixing cells method can accurately determine the whole key tie lines to a shift,regardless of the number of injection gas and reservoir fluid *** other methods of mixing cells,this method automatically corrects dispersion by additional contacts to achieve the low variation domain of tie line ***,the determination and implementation of the minimum miscibility enrichment are investigated.

关键词： Minimum miscible pressure Minimum miscibility enrichment Multiple mixing cells method Enhanced oil recovery Minimum tie line length method

Long term performance of warm mix asphalt versus hot mix asphalt

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Journal of Central South University 2013年第1期20卷 256-266页

作者： Ziari Hasan behbahani Hamid Izadi Amir Nasr Danial School of Civil Engineering Iran University of Science and Technology

The fatigue behavior, indirect tensile strength （ITS） and resilient modulus test results for warm mix asphalt （WMA） as well as hot mix asphalt （HMA） at different ageing levels were evaluated. Laboratory-prepared samples were aged artificially in the oven to simulate short-term and long term ageing in accordance with AASHTO R30 and then compared with unaged specimens. Beam fatigue testing was performed using beam specimens at 25 ℃ based on AASHTO T321 standard. Fatigue life, bending stiffness and dissipated energy for both unaged and aged mixtures were calculated using four-point beam fatigue test results. Three-point bending tests were performed using semi-circular bend （SCB） specimens at -10 ℃ and the critical mode I stress intensity factor k1 was then calculated using the peak load obtained from the load-displacement curve. It is observed that Sasobit and Rheofalt warm mix asphalt additives have a significant effect on indirect tensile strength, resilient modulus, fatigue behavior and stress intensity factor of aged and unaged mixtures.

关键词： warm mix asphalt hot mix asphalt fatigue behavior resilient modulus tensile strength stress intensity factor ageing

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