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Energy supply for water electrolysis systems using wind and solar energy to produce hydrogen: a case study of Iran

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Frontiers in Energy 2019年第3期13卷 539-550页

作者： Mostafa REZAEI Ali MOSTAFAEIPOUR mojtaba QOLIPOUR Mozhgan MOMENI Industrial Engineering Department Yazd UniversityYazd ***Iran

Due to acute problems caused by fossil fuels that threaten the environment, conducting research on other types of energy carriers that are clean and renewable is of great importance. Since in the past few years hydrogen has been introduced as the future fuel, the aim of this study is to evaluate wind and solar energy potentials in prone areas of Iran by the Weibull distribution function (WDF) and the Angstrom-Prescott (AP) equation for hydrogen production. To this end, the meteorological data of solar radiation and wind speed recorded at 10 m height in the time interval of 3 h in a five-year period have been used. The findings indicate that Manjil and Zahedan with yearly wind and solar energy densities of 6004 (kWh/m2) and 2247 0cWh/m2), respectively, have the greatest amount of energy among the other cities. After examining three different types of commercial wind turbines and photovoltaic (PV) systems, it becomes clear that by utilizing one set of Gamesa G47 turbine, 91 kg/d of hydrogen, which provides energy for 91 car/week, can be produced in Manjil and will save about 1347 L of gasoline in the week. Besides, by installing one thousand sets of X21-345 PV systems in Zahedan, 20 kg/d of hydrogen, enough for 20 cars per week, can be generated and 296 L of gasoline can be saved. Finally, the RETScreen software is used to calculate the annual CO2 emission reduction after replacing gasoline with the produced hydrogen.

关键词： wind energy solar energy water electrolysis hydrogen production Weibull distribution function (WDF) Angstrom丒Prescott (AP) equation

Constitutive model for monotonic and cyclic responses of loosely cemented sand formations

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第4期10卷 740-752页

作者： mojtaba Rahimi Dave Chan Alireza Nouri Department of Mechanical Engineering Azad UniversityKhomeinishahr BranchIsfahanIran Department of Civil and Environmental Engineering University of AlbertaEdmontonT6G 2W2Canada China Three Gorges University YichangChina

This paper presents a model to simulate the monotonic and cyclic behaviours of weakly cemented *** elastoplastic constitutive model within the framework of bounding surface plasticity theory is adopted to predict the mechanical behaviour of soft sandstone under monotonic and cyclic loadings. In this model, the loading surface always passes through the current stress state regardless of the type of loading. Destruction of the cementation bonds by plastic deformation in the model is considered as the primary mechanism responsible for the mechanical degradation of loosely cemented sands/weak *** model cyclic response, the unloading plastic and elastic moduli are formulated based on the loading/reloading plastic and elastic moduli. The proposed model was implemented in FLAC2D and evaluated against laboratory triaxial tests under monotonic and cyclic loadings, and the model results agreed well with the experimental observations. For cyclic tests, hysteresis loops are captured with reasonable accuracy.

关键词： Cyclic loading Monotonic loading Cemented sand Plasticity Constitutive model

Cu2O nanocrystals with various morphology:Synthesis,characterization and catalytic properties

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Chinese Chemical Letters 2017年第5期28卷 1125-1130页

作者： mojtaba Bagherzadeh Narges-alsadat Mousavi mojtaba Amini Sanjeev Gautam Jitendra Pal Singh Keun Hwa Chae Chemistry Department Sharif University of TechnologyTehranP.O.Box 11155-3615Iran Department of Chemistry Faculty of ScienceUniversity of MaraghehMaraghehIran Dr.SSBhatnagar University Institute of Chemical Engineering&Technology(SSB UICET)Panjab UniversityChandigarh 160-014India Advanced Analysis Center Korea Institute of Science and TechnologySeoul 136-791South Korea

Cu2O nanocubes,octahedra,spheres and truncated rhombic dodecahedral were prepared and their structural,morphological,and electronic properties were investigated by X-ray diffraction analysis.X-ray absorption near edge structure,scanning electron microscope and transmission electron microscope and X-ray absorption near edge ***2O nanocrystals were successfully employed to catalyze the 1,3-dipolar cycloaddition reaction for the synthesis of 1,4-disubstituted ***2O nanocubes and octahedral showed the superior catalytic performance in the cycloaddition *** results reveal that crystal-plane engineering of oxide catalysts is a useful strategy for developing efficient catalysts for organic reaction.

关键词： Nanocrystal Morphology Cu2O Azide-alkyne cycloaddition

Numerical Analysis of Complicated Heat and Mass Transfer inside a Wustite Pellet during Reducing to Sponge Iron by H_2 and CO Gaseous Mixture

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Journal of Iron and Steel Research International 2016年第11期23卷 1142-1150页

作者： Zare Ghadi ARIYAN Valipour MOHAMMAD SADEGH Biglari mojtaba Faculty of Mechanical Engineering Semnan University

Heat and mass transfer through a wustite pellet during converting to sponge iron was investigated. Pellet was reduced by a gaseous mixture containing CO and Hz. The grain model was considered to simulate gas solid reac- tion rate. A finite volume method （FVM） was implemented for solving the governing equations. The heat transfer mechanism around the pellet includes radiation and convection and within the pellet, effective heat transfer is consid- ered as a blend of particles conduction and intraparticle radiation. Heat and mass distribution along the radius of pel- let for two cases of reducing gases composed of pure H2 and pure CO was investigated. Local fractional reduction through the pellet was plotted to examine the heat and mass transfer behavior within the pellet and find their rele- vance with reduction degree. Afterwards, the impacts of pertinent parameters including gas ratio, pellet size and po rosity were studied.

关键词： heat transfer mass transfer wustite pellet reduction grain model

Enhancing optomechanical force sensing via precooling and quantum noise cancellation

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Science China(Physics,Mechanics & Astronomy) 2020年第1期63卷 44-54页

作者： Tesfay Gebremariam Ye-Xiong Zeng mojtaba Mazaheri Chong Li Department of Physics Ar ba Minch UniversityAr ba Minch 21Ethiopia School of Physics Dalian University of TechnologyDalian 116024China Department of Basic Science Hamedan University of TechnologyHamedan 65169-1-3733Iran

We theoretically investigate optomechanical force sensing via precooling and quantum noise cancellation in two coupled cavity optomechanical systems. We show that force sensing based on the reduction of noise can be used to dramatically enhance the force sensing and that the precooling process can effectively improve the quantum noise cancellation. Specifically, we examine the effect of optomechanical cooling and noise reduction on the spectral density of the noise of the force measurement; these processes can significantly enhance the performance of optomechanical force sensing, and setting up the system in the resolved sideband regime can lead to an optimization of the cooling processes in a hybrid system. Such a scheme serves as a promising platform for quantum back-action-evading measurements of the motion and a framework for an optomechanical force sensor.

关键词： hybrid optomechanical system coherent quantum noise cancellation force sensing

Synthesis of α-aminonitriles using silica-bonded N-propylpiperazine sulfamic acid as a recyclable catalyst

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Chinese Chemical Letters 2012年第10期23卷 1103-1106页

作者： Tahere Rahi mojtaba Baghernejad Khodabakhsh Niknam Department of Chemistry Gachsaran BranchIslamic Azad UniversityGachsaranlran Department of Chemistry Faculty of SciencesPersian Gulf UniversityBushehr 75169Iran

α-Aminonitriles were synthesized via a one-pot three-component condensation of aldehydes, amines, and trimethylsilyl cyanide using silica-bonded N-propylpiperazine sulfamic acid （SBPPSA） as a recyclable solid acid ... 详细信息

关键词： Silica-bonded N-propylpiperazine sulfamic acid α-Aminonitriles Aldehydes Amines Catalyst Solid acid

Synthesis and antibacterial activity of ethyl 2-amino-6-methyl-5-oxo-4-aryl-5,6-dihydro-4H-pyrano[3,2-c]quinoline-3-carboxylate

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Chinese Chemical Letters 2014年第3期25卷 431-434页

作者： Sakineh Asghari Samaneh Ramezani mojtaba Mohseni Department of Organic Chemistry Faculty of ChemistryUniversity of Mazandaran Nano and Biotechnology Research Group University of Mazandaran Department of Microbiology Faculty of SciencesUniversity of Mazandaran

The three-component reaction of 4-hydroxy-l-methyl-2（1H）-quinolinone, aromatic aldehydes and ethyl cyanoacetate was carried out in the presence of a catalytic amount of 4-dimethyl aminopyridine （DMAP） in aqueous ethanol. The reactions result in the formation of pyranoquinoline derivatives in excellent yields. Antibacterial activity has been evaluated against Gram positive and Gram negative bacteria for some of the synthesized compounds. The results indicated that these compounds are moderately effective against bacterial growth and their effectiveness is highest against Pseudomonas aeruginosa.

关键词： Three-component reactionPyranoquinoline4-Dimethyl aminopyridine (DMAP)Antibacterial activity

Evidence of the formation of landslide-dammed lakes in the Zagros Mountains range,Iran

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Journal of Mountain Science 2019年第10期16卷 2389-2403页

作者： Siyamack SHARAFI mojtaba YAMANI Mohsen EHTESHAMI-MOINABADI Department of Physical Geography Lorestan UniversityKhorram Abad***Iran Department of Physical Geography University of TehranTehran***Iran Department of Sedimentary Basins and Petroleum Shahid Beheshti UniversityTehran***Iran

Alternation of high and low resistance sedimentary beds,active tectonics,large rivers,and slope erosion in valleys consequently resulted in landslide in dammed lakes within the Zagros *** study presents the results in the analysis of geological and topographic data,satellite imageries,morphotectonics and hydrodynamics of drainage networks about the landslide dammed *** are four landslides in central Zagros(Zagros FoldThrust Belt,ZFTB)which have formed five dammed lakes named,Seymareh,Jaidar,Shur,Shimbar,and *** to the results,damming landslides occurred in the active-tectonic regions on the slopes of anticlines and in valleys with undercutting effects of rivers on their slopes consisting of alternations of loose and resistant *** studied landslide dams in narrow valleys are formed as a result of blocking river by sliding debris slopes and rock *** study also indicates the formation of Jaidar and Godar in one stage and the presence of Lake Terrace sequence in Seymareh,Shur and Shimbar *** observed sequences of terrace formation in these lakes are caused by four Seymareh Landslides followed by the three-stage excavation of Shur andShimbar lakes.

关键词： Landslide dams Lake terrace Central Zagros Iran

Electrochemical preparation and characterization of brain-like nanostructures of Y_2O_3

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Journal of Rare Earths 2013年第3期31卷 281-288页

作者： Mustafa Aghazadeh mojtaba Hosseinifard Mohammad Hassan Peyrovi Behrouz Sabour Department of Chemistry Islamic Azad UniversityShar-e-Ray BranchTehranIran Department of Chemistry Faculty of ScienceShahid Beheshti UniversityG.C.P.O.Box 19396-4716TehranIran

Nanostructured Y203 was successfully prepared via a two-step and template-free method. Firstly, yttrium hydroxide precursor was galvanostatically grown on the steel substrate from chloride bath by direct and pulse current deposition modes. Direct cunent deposition was carried out at the constant current density of 0.1 A/dm2 for 600 s. The pulse current was also performed at a typical on-time and off-time （ton=l S and Germ s） with an average current density of 0.05 A/dm2 （la=0.05 A/din2） for 600 s. The obtained hydroxide films were then scraped from the substrates and thermally converted into final oxide product via heat-treatment. Thermal behaviors and phase transformations during the heat treatment of the hydroxide powder samples were investigated by differential scanning calorimetry （DSC） and thermogravimetric analysis （TGA）. The final oxide products were characterized by means of X-ray diffraction （XRD）, Fourier transform infrared spectroscopy （FTIR） and scanning electron microscopy （SEM）. The results showed that the well-crystallized Y203 with brainand sphere-like morphology were achievable via pulse and direct deposition modes, respectively. It was concluded that pulse current cathodic electrodeposition offered a facile route for preparation ofnanostructured Y203.

关键词： cathodic electrodeposition heat-treatment electrochemical growth yttrium oxide brain-like nanostructure rare earths