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Microwave-induced Stereoselectivity in Synthesis of trans-4-Aryl-3-methyl-6-oxo-4,5,6,7-tetrahydro-2H- pyrazolo[3,4-b]pyridine-5-carbonitriles

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Chinese Journal of Chemistry 2011年第11期29卷 2373-2378页

作者： Rahmati, Abbas Alizadeh Kouzehrash, meysam Department of Chemistry University of lsfahan P. O. Box 81746-7344 Isfahan Iran

A facile synthesis of trans isomers of 4-aryl-3-methyl-6-oxo-4,5,6,7-tetrahydro-2H-pyrazolo[3,4-b]pyridine-5- carbonitriles via three-component condensation reaction of an aldehyde, 3-amino-5-methylpyrazole and ethyl cyanoacetate in acetonitrile has been developed under microwave irradiation. This one-pot reaction proceeds with-out any catalyst in short times and gives the product in high selectivities and high yields.

关键词： multi-component condensation reactions microwave pyrazolo[3,4-b]pyridine 3-amino-5- methylpyrazole

Synthesis of novel uracil based 2,5-diaminofurans using multi-component reactions

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Chinese Chemical Letters 2012年第6期23卷 677-680页

作者： Robabeh Baharfar Seyed meysam Baghbanian Department of Chemistry University of MazandaranP.O.Box 47415Babolsarlran

A simple synthesis of highly functionalized 2,5-diaminofurans based pyrimidine derivatives from 1-（carboxymethyl）uracil via a multi-component reaction is described. The reactive 1：1 intermediate produced from the reaction of tert-butyl isocyanide and dialkyl acetylenedicarboxylates was trapped at room temperature by 1-（carboxymethyl）uracil derivatives to yield polyfunctio- nalized furan rings in fairly good yields.

关键词： Multi-component reactions 2,5-Diaminofurans 1-(Carboxymethyl)uracil tert-Butyl isocyanide Dialkyl acetylene-dicarboxylate

Simultaneous determination of steroid drugs in the ointment via magnetic solid phase extraction followed by HPLC-UV

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Journal of Pharmaceutical Analysis 2018年第4期8卷 250-257页

作者： Yadollah Yamini meysam Safari Maryam Shamsayei Department of Chemistry Tarbiat Modares University Department of Chemical Engineering Kermanshah University of Technology

The copper-coated iron oxide nanoparticles with core-shell were produced by deposition of a Cu shell on Fe3 O4 NPs through reduction of Cu2 tions in solution using NaB H4. Subsequently, the organosulfur compound, bis-（2,4,4-trimethylpentyl）-dithiophosphinic acid（b-TMP-DTPA）, was used to form self-assembled monolayer in order to modify sorbent＇s surface via covalent bonding between Cu and thiol（–SH）terminal groups. The prepared magnetic nanoparticles were characterized by using Fourier transform infrared（FT-IR） spectroscopy, scanning electron microscopy（SEM）, transmission electron microscope（TEM）, vibrating sample magnetometer（VSM） and thermo gravimetric analysis（TGA）. Then, the application of this new sorbent was investigated to extract the steroid drugs in ointment samples with the aid of ultrasound. An external magnetic field was applied to collect the magnetic nanoparticles（MNPs）. The extracted analytes were desorbed using acetonitrile. The obtained extraction solution was analyzed by HPLC-UV. The main affecting factors on the extraction efficiency including p H, sonication time, amount of sorbent, salt concentration, and desorption conditions were optimized in detail. Under the optimum conditions, good linearity was obtained in the range of 2.5–250.0 mg/L with reasonable linearity（R24 0.99） and the limits of detection（LODs） ranged between 0.5 and 1.0 mg/L（based on S/N ？ 3）.Repeatability（intra-day precision） based on five replicates and preconcentration factors were calculated to be 3.6%–4.7% and 87–116, respectively. Relative recoveries in ointment samples at two spiked levels of the target analytes were obtained in the range of 90.0%–103.2%. The results illustrated that the Fe3 O4@Cu@ b-TMP-DTPA NPs have the capability of extraction of steroid drugs from ointment samples.

关键词： Magnetic nanoparticles Steroid drug Ointment High performance liquid chromatography Self-assembled monolayer

Service restoration in distribution networks using combination of two heuristic methods considering load shedding

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Journal of Modern Power Systems and Clean Energy 2015年第4期3卷 556-564页

作者： meysam GHOLAMI Jamal MOSHTAGH Naji GHADERNEJAD Department of Electrical Engineering University of KurdistanKurdistanIran West Regional Electrical Company KermanshahIran

Two heuristic methods are proposed to find an effective and fast solution in modern power distribution *** solving the service restoration problem in distribution networks,switch selection indices based on an analytic approach and a practicable heuristic graph-based method are *** formulation of the problem includes four different objective functions:1)maximizing the total load restored;2)minimizing the number of switching operations;3)maximizing the top priority restored load;4)minimizing load shedding.A suitable evaluation of switch indices is used for all candidate tie switches(TSs)in the network to find the best solution and decrease the number of switching operations.A new graph-based approach is utilized for finding the best sectionalizes switch(SS)and minimizing the voltage *** accuracy and the validity of the approach are tested in two standard electrical distribution *** results of the approach are used for IEEE 69-bus and IEEE 119-bus test case.

关键词： Service restoration Modern distribution networks Smart grid Switch indices Graph-based method

Mechanical properties of stabilized zirconia nanocrystalline EB-PVD coating evaluated by micro and nano indentation

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Journal of Advanced Ceramics 2013年第4期2卷 333-340页

作者： meysam KESHAVARZ Mohd Hasbullah IDRIS Norhayati AHMAD Department of Materials Science and Engineering Faculty of Mechanical EngineeringUniversiti Teknologi Malaysia81310 UTM Johor BahruJohorMalaysia

Yttria-stabilized zirconia(YSZ)thin nanocrystalline coatings at different substrate preheating temperatures were deposited via electron beam-physical vapour deposition(EB-PVD).Nanocrystalline ZrO_(2)-Y_(2)O_(3) was deposited on the bond coat in order to compensate for the coefficient of thermal expansion(CTE),which can be functionalized as a thermal barrier coating(TBC).The aim of this study was to evaluate mechanical properties with respect to adhesion of zirconia nanocrystalline’s top ceramic layer to the interfacial bond coat by utilizing micro and nano indentation *** the present paper,the structural studies were carried out using X-ray diffraction(XRD)analysis of coating content(8 mol%of Y_(2)O_(3)).The tetragonal phase of stabilized zirconia was *** emission scanning electron microscopy(FESEM)and atomic force microscopy(AFM)were employed to characterize the coatings’morphology and *** mechanical behavior of ZrO_(2)-Y_(2)O_(3) thin films under point loading conditions was studied by nanoindentation using a Berkovich indenter with 130 nm tip ***,adhesion of top coat to the interfacial underlying metallic bond coat known as MCrAlY(M=Ni,Co)was estimated according to the highest peak load tests;for a 120 mN peak load,the film manifested tolerable adhesion ***,nanoindentation of ZrO_(2)-Y_(2)O_(3) nanostructure deposited at 1050℃substrate preheating temperature produced the highest hardness value of about 21.7 *** micro hardness was utilized with the aid of the Tabor equation in order to achieve deeper insight into the correlation between adhesion and deposition process parameters.

关键词： zirconia nanoindentation nanocrystalline electron beam-physical vapour deposition(EB-PVD) thermal barrier coating(TBC)

Wettability alteration and retention of mixed polymer-grafted silica nanoparticles onto oil-wet porous medium

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Petroleum Science 2021年第3期18卷 962-982页

作者： Hamid Daneshmand Masoud Rezaeinasab Masoud Asgary meysam Karimi Department of Physics University of TehranTehranIran Department of Chemistry Faculty of ScienceYazd UniversityYazdIran Department of Materials Engineering Tarbiat Modares UniversityTehranIran Department of Material Science Shahreza BranchIslamic Azad UniversityIsfahanIran

Enhanced oil recovery(EOR)processes are applied to recover trapped or residual oil in the reservoir rocks after primary and secondary recovery *** the wettability of the rock from oil-wet to water-wet is named wettability *** is an important factor for *** to their unique properties,nanoparticles have gained great attention for improving oil *** the promising results,the main challenges of applying nanoparticles are related to the colloidal stability of the nanofuids in the harsh conditions of the *** recent years,polymer-grafted nanoparticles have been considered as novel promising materials for *** obtained results showed that adding a hydrophobic agent trimethoxy(propyl)silane on the surface of modifed silica nanoparticles with polyethylene glycol methyl ether has an efective role in improving retention and wettability alteration,especially in the oil-wet substrate due to hydrophobic *** modifed silica nanoparticle by mixed polyethylene glycol methyl ether(Mn~5000)and trimethoxy(propyl)silane showed a proper performance at a concentration of 1000 ppm and a salinity range of 2000-40,000 *** obtained fndings can help for a better understanding of the silica nanofuid modifcation with both hydrophilic and hydrophobic agents for the EOR application of near-wellbore.

关键词： Wettability alteration Retention Silica nanoparticle Surface modifcation Enhanced oil recovery

A Quantum Chemical Investigation on the Antioxidant Activity of Licoisoflavone Derivatives

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Chinese Journal of Structural Chemistry 2013年第9期32卷 1404-1414页

作者： MALIHE Najafi meysam Najafi MOHAMMAD Najafi Department of Mathematics Anar Branch Islamic Azad University

In this paper,21 substituents with various electron donating and electron withdrawing characters were placed in the available positions of Licoisoflavone in order to study their effect on the three O–H bond dissociation enthalpies and ionisation potential via DFT/B3LYP *** show that the B-ring is more important than the A-ring from the BDE and IP point of view because the radical structure formed after hydrogen atom abstraction from the 4-OH group can be stabilized by the resonance between the three *** results show that intramolecular hydrogen bonding effects are able to considerably stabilize the parents and *** NBO analysis results also confirmed the intramolecular hydrogen bond *** formation of strong intramolecular hydrogen bonds and suitable spin density distributions in several radicals result in low BDE and IP *** calculated BDE and IP values have been correlated with Hammett *** found dependencies are suitably linear,which can be important for the synthesis of novel antioxidants based on Licoisoflavone.

关键词： antioxidant licoisoflavone hydrogen Bond substituent effect

Edge-Dependent Electronic and Magnetic Characteristics of Freestanding β_(12)-Borophene Nanoribbons

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Nano-Micro Letters 2018年第1期10卷 124-136页

作者： Sahar Izadi Vishkayi meysam Bagheri Tagani Department of Physics Computational Nanophysics Laboratory (CNL) University of Guilan

This work presents an investigation of nanoribbons cut from β_(12)-borophene sheets by applying the density functional theory. In particular, the electronic and magnetic properties of borophene nanoribbons(BNR) are studied. It is found that all the ribbons considered in this work behave as metals, which is in good agreement with the recent experimental results. β_(12)-BNR has significant diversity due to the existence of five boron atoms in a unit cell of the sheet. The magnetic properties of the ribbons are strongly dependent on the cutting direction and edge profile. It is interesting that a ribbon with a specific width can behave as a normal or a ferromagnetic metal with magnetization at just one edge or two edges. Spin anisotropy is observed in some ribbons, and the magnetic moment is not found to be the same in both edges in an antiferromagnetic configuration. This effect stems from the edge asymmetry of the ribbons and results in the breaking of spin degeneracy in the band structure. Our findings show that β_(12) BNRs are potential candidates for next-generation spintronic devices.

关键词： Borophene nanoribbons Electronic and magnetic properties Density functional theory

Life cycle assessment of oxygen-18 production using cryogenic oxygen distillation

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Chinese Journal of Chemical Engineering 2018年第9期26卷 1960-1966页

作者： meysam Akbarian Shourkaei Abbas Rashidi Javad Karimi-Sabet Faculty of Engineering University of Mazandaran Material and Nuclear Fuel Research School (MNFRS) Nuclear Science and Technology Research Institute

In this study, life cycle assessment of oxygen-18 by using cryogenic distillation of oxygen is performed using SimaPro 8.3 software. Life cycle assessment is performed to understand the environmental profile and hotspots of this process in order to be used in design and development. Simulation of oxygen-18 process is executed by Hysys software, and the required inputs and outputs for inventory of life cycle were acquired. By doing life cycle assessment and considering achieved results after characterization and normalization of inventory data it has been investigated that in the majority of environmental impacts electricity consumption has a huge contribution relative to other parts of the system like liquefied oxygen production from air separation unit,required facilities for air separation and oxygen-18 units, and needed transportation. Also, among 17 impact categories investigated in ReCiPe impact assessment method, fossil depletion, climate change(human health),particulate matter formation, climate change(ecosystem), human toxicity, and metal depletion have the most contribution in entire environmental loads respectively. Furthermore, sensitivity analysis showed that changing life cycle impact assessment method from ReCiPe to IMPACT 2002+ has no significant effect on acquired results and results are confident. In addition, assumption of market for depleted oxygen from heavy isotopes which is withdrawn from top of distillation columns showed some positive effects compared to first case and environmental impacts resulted from liquefied oxygen production(feed) reduced but because of huge contribution of electricity consumption compared to other sections, this positive effect has no remarkable influence on entire environmental loads of product system.

关键词： Life cycle assessment Oxygen- 18 production Cryogenic distillation Isotope separation