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An efficient chemoselective synthesis of O-vinylaryl systems using acetylenic esters and dihydroxybenzenes in the presence of triphenylphosphine or alkyl isocyanides

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Chinese Chemical Letters 2010年第2期21卷 175-178页

作者： Robabeh Baharfar mohammad javad Taghizadeh Majid Ahmadian Seyed Meysam Baghbanian Department of Chemistry University of MazandaranBabolsar 47415Iran

The addition of 2,4-dihydroxyaceto(and benzo)phenone to propiolic ester is catalyzed by triphenylphosphine or tert-butyl isocyanide to form O-vinyl aryl derivatives in fairly good yields.

关键词： 2 4-Dihydroxyaceto(and benzo)phenone Triphenylphosphine Propiolic ester tert-Butyl isocyanide

DEM simulation of confining pressure effects on crack opening displacement in hydraulic fracturing

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International Journal of Mining Science and Technology 2016年第4期26卷 557-561页

作者： Abdollahipour Abolfazl Fatehi Marji mohammad Yarahmadi Bafghi Alireza Gholamnejad javad Faculty of Mining and Metallurgical Engineering Yazd University

Hydraulic fracture is one of the key methods in well stimulation to increase production of oil and *** Opening Displacement(COD) is of great importance in this method since it is in direct relation with permeability and production *** this paper COD is measured by a distinct element model which has been validated by an exact solution.A comprehensive study has been performed on confining pressure effect on COD which is neglected in the analytical *** results showed that confining pressure considerably affects COD.A multi-parameter regression(considering effect of confining pressure,rock mass properties and fluid pressure) was performed on numerical results which resulted in an *** proposed equation considers the effect of confining pressure and its results are in good agreement with numerical results.

关键词： Hydraulic lracture COD Numerical analysis Confining pressure Regression

Modeling of liquid hydrocarbon products from syngas

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International Journal of Coal Science & Technology 2019年第1期6卷 27-36页

作者： Hossein Atashi Mohsen Hajisafari Fatemeh Rezaeian mohammad javad Parnian Department of Chemical Engineering University of Sistan and Baluchestan ZahedanIran School of Chemical Engineering Iran University of Science and TechnologyTehranIran

The modeling of hydrocarbon selectivity and CO conversion of the Fischer-Tropsch synthesis over Fe-Ni/Al2O3 catalyst by using coupled artificial neural networks (ANN) and design of experiment (DOE) approaches were investigated. The variable parameters for modeling consisted of the pressure range between 2 and 10 bar and the temperature range of 523-573 K. After training of data by ANN and determination of DOE points by central composite design (CCD), the results were compiled together for producing simulated data used in the response surface method (RSM). The RSM was used as an applied mathematics model to dem on strate the CO conversi on and selectivity of hydrocarbons depende nee on the CO hydrogenation conditions. The results indicated that CO conversion and Cg selectivity increased with rising both temperature and pressure. The methane selectivity showed upward trend as the temperature in creased. It also in creased by decreasing pressure. Finally, the optimization of the catalytic process was carried out and conditions with maximum desired product were obtained. A comparison of experimental values and RSM values show that the RSM equations are able to predict the behavior of experimental data.

关键词： Fischer-Tropsch synthesis Artificial neural network Response surface method CO conversion Hydrocarbon selectivity

Simultaneous effects of joint spacing and joint orientation on the penetration rate of a single disc cutter

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Mining Science and Technology 2011年第4期21卷 507-512页

作者： Bejari Hadi Kakaie Reza Ataei mohammad Khademi-Hamidi javad Faculty of Mining Petroleum and Geophysics EngineeringShahrood University of TechnologySemnanIran Faculty of Mining Petroleum and Geophysics EngineeringShahrood University of TechnologySemnanIran Faculty of Mining Metallurgy EngineeringAmirkabir University of TechnologyTehranIran

This paper describes the influence of joint spacing and joint orientation on the penetration rate of a Tunnel Boring Machine （TBM） disc cutter as modeled by the Discrete Element Method （DEM）. The input data for the siLmulations were obtained from the sandstone along the AIborz tunnel that is currently being excavated in Iran using a 5.2 m diameter open TBM. Three joint spacings, 150, 200, and 300 mm, were modeled together with seven values of joint orientation; 0°, 15°, 30°, 45°, 60°, 75°, and 90°. The results show that the penetration increases when joint orientation increases from 0° to 75°, but it decreases as the joint orientation increases further from 75° to 90°. This is true for each joint spacing. In addition, for a given joint orientation increasing the joint spacing causes the TBM penetration to decrease. The optimum joint orientation, from the viewpoint of TBM penetration, is about 60-75°.

关键词： Joint orientation Joint spacing TBM DEM

Effects of different treatments on seed germination and breaking seed dormancy of Prosopis koelziana and Prosopis Juliflora

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Journal of Forestry Research 2011年第1期22卷 35-38页

作者： Salman Zare Ali Tavili mohammad javad Darini Department of Arid and Mountainous Regions Reclamation Faculty of Natural Resource University of Tehran Karaj Iran

For improving seed germination of Prosopis koelziana and Prosopis juliflora, different treatments of seeds were conducted, including scarification with sulfuric acid 98% for 10 and 15 min, sandy paper, hot water for 5 and 10 min, potasium nitrate 0.1%, gibberellic acid at 250 mg·L^-1 and 500 mg·L^-1 and combinational treatment of scarification with gibberellic acid of 250 mg·L^-1 and 500 mg·L^-1. The results show that scarifications with sandy paper and sulfuric acids 98% were the most effective treatments on breaking seed dormancy and seed germination induction. Scarification with sulfuric acid 98% for 15 min was the best treatment. According to the positive effect of scarification and lack of reaction of seeds against KNO3 and gibberellic acid, the kind of seed dormancy was determined as exogenous.

关键词： breaking seed dormancy seed germination sulfuric acid Prosopis koelziana Prosopis juliflora

Interplay between temperature-dependent strengthening mechanisms and mechanical stability in high-performance austenitic stainless steels

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2182-2188页

作者： mohammad javad Sohrabi Hamed Mirzadeh Saeed Sadeghpour Milad Zolfipour Aghdam Abdol Reza Geranmayeh Reza Mahmudi School of Metallurgy and Materials Engineering College of EngineeringUniversity of Tehran14395-515 TehranIran Centre for Advanced Steels Research Materials and Mechanical EngineeringUniversity of Oulu90014 OuluFinland Department of Mechanical Engineering College of EngineeringUniversity of Tehran14395-515 TehranIran

The effects of deformation temperature on the transformation-induced plasticity(TRIP)-aided 304L,twinning-induced plasti-city(TWIP)-assisted 316L,and highly alloyed stable 904L austenitic stainless steels were compared for the first time to tune the mechan-ical properties,strengthening mechanisms,and strength-ductility *** this purpose,the scanning electron microscopy(SEM),electron backscattered diffraction(EBSD),X-ray diffraction(XRD),tensile testing,work-hardening analysis,and thermodynamics calcu-lations were *** induced plasticity effects led to a high temperature-dependency of work-hardening behavior in the 304L and 316L stainless *** the deformation temperature increased,the metastable 304L stainless steel showed the sequence of TRIP,TWIP,and weakening of the induced plasticity mechanism;while the disappearance of the TWIP effect in the 316L stainless steel was also ***,the solid-solution strengthening in the 904L superaustenitic stainless steel maintained the tensile properties over a wide temper-ature range,surpassing the performance of 304L and 316L stainless *** this regard,the dependency of the total elongation on the de-formation temperature was less pronounced for the 904L alloy due to the absence of additional plasticity *** results re-vealed the importance of solid-solution strengthening and the associated high friction stress for superior mechanical behavior over a wide temperature range.

关键词： austenitic stainless steels mechanical behavior stacking fault energy metastability mechanical twinning

AFAR:adaptive fuzzy ant-based routing for communication networks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第12期9卷 1666-1675页

作者： Seyed javad MIRABEDINI mohammad TESHNEHLAB M.H.SHENASA Ali MOVAGHAR Amir Masoud RAHMANI Engineering Department Science and Research BranchIslamic Azad UniversityTehranIran Control Department K.N.Toosi Technology UniversityTehranIran Computer Department Sharif UniversitTehranIran

We propose a novel approach called adaptive fuzzy ant-based routing (AFAR), where a group of intelligent agents (or ants) builds paths between a pair of nodes, exploring the network concurrently and exchanging obtained information to up-date the routing tables. Routing decisions can be made by the fuzzy logic technique based on local information about the current network state and the knowledge constructed by a previous set of behaviors of other agents. The fuzzy logic technique allows multiple constraints such as path delay and path utilization to be considered in a simple and intuitive way. Simulation tests show that AFAR outperforms OSPF, AntNet and ASR, three of the currently most important state-of-the-art algorithms, in terms of end-to-end delay, packet delivery, and packet drop ratio. AFAR is a promising alternative for routing of data in next generation networks.

关键词： Adaptive fuzzy routing algorithm Swarm intelligence Routing table Communication network Packet delay,Throughput

Quenching effect of deferoxamine on free radical-mediated photon production in luminol and ortho-phenanthroline-dependent chemiluminescence

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Chinese Chemical Letters 2014年第4期25卷 630-634页

作者： Mahdi Parvar Jalil Mehrzadn mohammad javad Chaichi Saman Hosseinkhani Hamid Golchoubian Faculty of Chemistry Mazandaran University Department of Pathobiology Faculty of Veterinary MedicineFerdowsi University of Mashhad Veterinary Biotechnology Research Group Institute of BiotechnologyFerdowsi University of Mashhad Department of Biochemistry Faculty of Biological SciencesTarbiat Modares University

Removing excessive free radicals （FRs） by a synthetic chemical might give a clue for treatment of many iron-mediated diseases. Deferoxamine （DFO） can be one of the chemicals of choice for the clue. To investigate photoredox properties of DFO, its quenching effect on superoxide radical （O2°）, hydrogen peroxide （H202） and hydroxyl radical （OH~） was examined using luminol and ortho-phenanthroline （o- phen） chemiluminescence （CL） systems and UV-vis spectrophotometry. Stern-Volmer equation was also used for the CL kinetics. The observed quenching effect of DFO on CL]photon production in luminol and o-phen CL systems strongly confirmed the static arm of quenching properties of DFO on OH° and H2O2, but much less pronounced on O2^-°; the quenching property was maximal when iron was involved in the reaction systems. The Stern-Volmer plots in the designed photochemical reaction systems also confirmed a potent quenching effect of DFO on FR-mediated CL. Our study highlights strong photoreducing and antioxidant properties of DFO with huge quenching capacity on excessive FRs, and thus implies its promising prospects for therapeutic applications.

关键词： Chemiluminescence Deferoxamine Free radicals Photon production Stern-Volmer plot

Numerical study of n-heptane/benzene separation by thermal diffusion column

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Chinese Journal of Chemical Engineering 2019年第8期27卷 1745-1755页

作者： Neda Hashemipour javad Karimi-Sabet Kazem Motahari Saeed Mahruz Monfared Younes Amini mohammad Ali Moosavian Department of Chemical Engineering Faculty of EngineeringArak UniversityArakIran Material and Nuclear Fuel Research School(MNFRS) Nuclear Science and Technology Research InstituteTehranIran Department of Chemical and Petroleum Engineering Sharif University of TechnologyTehranIran Department of Chemical Engineering Isfahan University of TechnologyIsfahanIran School of Chemical Engineering Faculty of EngineeringUniversity of TehranTehranIran

In this article,numerical simulations are performed to investigate the performance of the thermal diffusion column for the separation of n-heptane/benzene *** present work tried to optimize column by analyzing significant parameters such as feed flow rate,temperature and *** order to obtain the hydrodynamic and temperature and mass distribution inside thermal diffusion column,computational fluid dynamic(CFD) method is applied to solve the Navier-Stocks *** simulations are conducted to study the main parameters in both stationary and time-dependent *** using the separation work unit as a function of cut,the optimal cut for maximum SWU occurs within a limited range of 0.47-0.5 for feed rate between 0.5 and 4 g min^-*** findings reveal that the optimum feed rate in the range of optimum cut is about 1 g min^-*** transient study,results show that the best cut for reaching to steady-state condition is θ=0.5.

关键词： Thermal diffusion column(TDC) Computational fluid dynamic Separative work unit n-Heptane/benzene separation