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Applying density functional theory on tautomerism in 3,4- dihydropyrimidin-2(1H)-ones

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中国化学前沿:英文版 2011年第2期6卷 142-146页

作者： Asadollah FARHADI mohammad ali takassi Faculty of Science University of Petroleum Technology AhwazAhwaz 61981-44471Iran

In the present study,the density functional theory(DFT)and Gibbs free energy calculations were performed to investigate the stability and tautomerism of C4-substituted-3,4-dihydropyrimidin-2(1H)-*** different forms are possible for the ethyl 3,4-dihydropyrimidinones(ethyl 4-aryl-6-methyl-3,4-dihydropyrimidin-2(1H)-one-5-carboxylates,ethyl 4-aryl-2-hydroxy-6-methyl-1,4-dihydropyrimidine-5-carboxylates and ethyl 4-aryl-2-hydroxy-6-methyl-3,4-dihydropyrimidine-5-carboxylates)forms that the most stable form is ethyl 4-aryl-6-methyl-3,4-dihydropyrimidin-2(1H)-one-5-carboxylates(keto-form).The obtained data showed that the substitution on the C4-substitut position can be effective on the equilibrium constant(K_(eq)).

关键词： Gibbs free energy density functional theory(DFT) tautomerism dihydropyrimidin-2(1H)-ones Keto-Form

Experimental investigation into L-Arg and L-Cys eco-friendly surfactants in enhanced oil recovery by considering IFT reduction and wettability alteration

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Petroleum Science 2020年第1期17卷 105-117页

作者： Hamed Foroughi Asl Ghasem Zargar Abbas Khaksar Manshad mohammad ali takassi Jagar A.ali alireza Keshavarz Department of Petroleum Engineering Abadan Faculty of Petroleum EngineeringPetroleum University of Technology(PUT)AbadanIran Department of Petroleum Engineering Ahwaz Faculty of Petroleum EngineeringPetroleum University of Technology(PUT)AhwazIran Department of Petroleum Engineering Faculty of EngineeringSoran UniversitySoranKurdistan RegionIraq Department of Petroleum Engineering College of EngineeringKnowledge UniversityErbilKurdistan RegionIraq School of Engineering Edith Cowan UniversityJoondalupWA 6027Australia

Surfactant flooding is an important technique used to improve oil recovery from mature oil reservoirs due to minimizing the interfacial tension(IFT)between oil and water and/or altering the rock wettability toward water-wet using various surfactant agents including cationic,anionic,non-ionic,and amphoteric *** this study,two amino-acid based surfactants,named lauroyl arginine(L-Arg)and lauroyl cysteine(L-Cys),were synthesized and used to reduce the IFT of oil–water systems and alter the wettability of carbonate rocks,thus improving oil recovery from oil-wet carbonate *** synthesized surfactants were characterized using Fourier transform infrared spectroscopy and nuclear magnetic resonance analyses,and the critical micelle concentration(CMC)of surfactant solutions was determined using conductivity,pH,and turbidity *** results showed that the CMCs of L-Arg and L-Cys solutions were 2000 and 4500 ppm,*** was found that using L-Arg and L-Cys solutions at their CMCs,the IFT and contact angle were reduced from 34.5 to 18.0 and15.4 mN/m,and from 144°to 78°and 75°,***,the L-Arg and L-Cys solutions enabled approximately 11.9%and 8.9%additional recovery of OOIP(original oil in place).It was identified that both amino-acid surfactants can be used to improve oil recovery due to their desirable effects on the EOR mechanisms at their CMC ranges.

关键词： Chemical EOR Amino-acid surfactant IFT Wettability Coreflooding

Investigation of the interaction of ethyl acetoacetate with nano alumina particle as Lewis acid in acetonitrile solvent

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中国化学前沿:英文版 2011年第3期6卷 248-252页

作者： Asadollah FARHADI mohammad ali takassi Mandana DAYER Faculty of Science Petroleum University of TechnologyAhwaz 61981-44471Iran Department of Chemistry Science and Research BranchIslamic Azad UniversityKhouzestanIran

The enol form of ethyl acetoacetate(EAA)displays interesting spectroscopic characteristics;this form of ethyl acetylacetate is very important in condensation *** this investigation,we have studied the interactions and the complex formation constants(K_(f))with nano alumina(10–20 nm)particle and alumina(mesh 135)compounds as Lewis acids in the acetonitrile solvent using absorption spectroscopy and related ***,in this study we calculated the thermodynamic parameters of this *** trend of reactivity of the ethyl acetoacetate(EAA)complexes toward the above Lewis acids,based on the solvent as follows:nano alumina compound>alumina compound.

关键词： complex formation constant ethyl acetoacetate nano alumina alumina thermodynamic

Computational evaluation concerning the deviation of the atoms in 1-and 4-postions on the six-member ring and the effects on ^(1)HNMR chemical shift

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中国化学前沿:英文版 2011年第2期6卷 91-97页

作者： Asadollah FARHADI mohammad ali takassi Hamid Reza MEMARIAN Mousa SOLEYMANI Faculty of Science University of Petroleum TechnologyAhwaz 61981-44471Iran Department of Chemistry Faculty of ScienceUniversity of IsfahanIsfahan 81746-73441Iran

Density functional theory(DFT)calculations were carried out on some cyclohexane derivatives to investigate the deviation atoms on the 1-and 4-positions of chair *** deviations of chair plane of two position in the cyclohexane derivatives were calculated at the B3LYP/6–31++G(d,p)***,we investigated the correlation between deviations of two positions from chair plane on the chemical shift hydrogen atoms on the 4-position.

关键词： cyclohexane heterocyclohexane deviation B3LYP/6-31++G(d p) chemical shift

A Novel γ-Alumina Supported Fe-Mo Bimetallic Catalyst for Reverse Water Gas Shift Reaction

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Chinese Journal of Chemical Engineering 2013年第9期21卷 1007-1014页

作者： Abolfazl Gharibi Kharaji Ahmad Shariati mohammad ali takassi Petroleum University of Technology Ahwaz Faculty of Petroleum Engineering Chemical Engineering DepartmentAhwaz Iran Petroleum University of Technology Ahwaz Faculty of Petroleum Engineering Science Department Ahwaz Iran

In reverse water gas shift （RWGS） reaction COa is converted to CO which in turn can be used to pro- duce beneficial chemicals such as methanol. In the present study, Mo/AlaO3, Fe/AlaO3 and Fe-Mo/Al2O3 catalysts were synthesised using impregnation method. The structures of catalysts were studied using X-ray diffraction （XRD）, Brunauer-Emmett-Teller （BET） method, inductively coupled plasma atomic emission spectrometer （ICP-AES）, temperature programmed reduction （H2-TPR）, CO chemisorption, energy dispersive X-ray （EDX） and scanning electron microscopy （SEM） techniques. Kinetic properties of all catalysts were investigated in a batch re- actor for RWGS reaction. The results indicated that Mo existence in structure of Fe-Mo/AlzO3 catalyst enhances its activity as compared to Fe/AlaO3. This enhancement is probably due to better Fe dispersion and smaller particle size of Fe species. Stability test of Fe-Mo/AlzO3 catalyst was carried out in a fixed bed reactor and a high CO yield for 60 h of time on stream was demonstrated. Fez（MoO4）3 phase was found in the structures of fresh and used catalysts. TPR results also indicate that Fez（MoO4）3 phase has low reducibility, therefore the Fe2（MoO4）3 phase significantly inhibits the reduction of the remaining Fe oxides in the catalyst, resulted in high stability of Fe-Mo/Al2O3 catalyst. Overall, this study introduces Fe-Mo/Al2O3 as a novel catalyst with high CO yield, almost no by-products and fairly stable for RWGS reaction.

关键词： reverse water gas shift reaction Fe-Mo/Al2O3 catalyst selectivity stability reducibility

Seismic control of multi-degrees-of-freedom structures by vertical mass isolation method using MR dampers

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 503-510页

作者： Mohamad Shahrokh Abdi Masoud Nekooei mohammad-ali Jafari Department of Civil Engineering Marivan BranchIslamic Azad UniversityMarivan ***Iran Department of Civil Engineering Science and Research BranchIslamic Azad UniversityTehran ***Iran Structural Department of Transmission and Distribution Research Center Niroo Research Institute(NRI)Tehran ***Iran

Vertical mass isolation(VMI)is one of the novel methods for the seismic control of *** this method,the entire structure is assumed to consist of two mass and stiffness subsystems,and an isolated layer is located among *** this study,the magnetorheological damper in three modes:passive-off,passive-on,and semi-active mode with variable voltage between zero and 9 volts was used as an isolated layer between two ***-degrees-of-freedom structures with 5,10,and 15 floors in two dimensions were examined under 11 pairs of near field *** each level,the displacement of MR dampers was taken into *** responses of maximum displacement,maximum inter-story drift,and maximum base shear in controlled and uncontrolled buildings were compared to assess the suggested approach for seismic control of the *** to the results,the semi-active control method can reduce the response by more than 12%compared to the uncontrolled mode in terms of maximum displacement of the mass subsystem of the *** method can reduce more than 16%and 20%of the responses compared to the uncontrolled mode in terms of maximum inter-story drift and base shear of the structure,respectively.

关键词： seismic control vertical mass isolation base shear magnetorheological damper semi-active control

An Improved Binary Quantum-based Avian Navigation Optimizer Algorithm to Select Effective Feature Subset from Medical Data:A COVID-19 Case Study

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Journal of Bionic Engineering 2024年第1期21卷 426-446页

作者： ali Fatahi mohammad H.Nadimi-Shahraki Hoda Zamani Faculty of Computer Engineering Najafabad BranchIslamic Azad UniversityNajafabad ***Iran Big Data Research Center Najafabad BranchIslamic Azad UniversityNajafabad ***Iran

Feature Subset Selection(FSS)is an NP-hard problem to remove redundant and irrelevant features particularly from medical data,and it can be effectively addressed by metaheuristic ***,existing binary versions of metaheuristic algorithms have issues with convergence and lack an effective binarization method,resulting in suboptimal solutions that hinder diagnosis and prediction *** paper aims to propose an Improved Binary Quantum-based Avian Navigation Optimizer Algorithm(IBQANA)for FSS in medical data preprocessing to address the suboptimal solutions arising from binary versions of metaheuristic *** proposed IBQANA’s contributions include the Hybrid Binary Operator(HBO)and the Distance-based Binary Search Strategy(DBSS).HBO is designed to convert continuous values into binary solutions,even for values outside the[0,1]range,ensuring accurate binary *** the other hand,DBSS is a two-phase search strategy that enhances the performance of inferior search agents and accelerates *** combining exploration and exploitation phases based on an adaptive probability function,DBSS effectively avoids local *** effectiveness of applying HBO is compared with five transfer function families and thresholding on 12 medical datasets,with feature numbers ranging from 8 to 10,***'s effectiveness is evaluated regarding the accuracy,fitness,and selected features and compared with seven binary metaheuristic ***,IBQANA is utilized to detect *** results reveal that the proposed IBQANA outperforms all comparative algorithms on COVID-19 and 11 other medical *** proposed method presents a promising solution to the FSS problem in medical data preprocessing.

关键词： Feature subset selection Optimization Binary metaheuristic algorithms Bioinspired Machine learning Medical datasets

Sacrificial piles as a countermeasure against local scour around underwater pipelines

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Water Science and Engineering 2024年第2期17卷 187-196页

作者： Forough Raeisi Seyed mohammad ali Zomorodiann Masih Zolghadr Hazi mohammad Azamathulla Department of Water Engineering Shiraz UniversityShiraz ***Iran Department of Water Sciences Engineering Jahrom UniversityJahrom ***Iran Department of Civil and Environmental Engineering The University of the West IndiesSt.Augustine CampusTrinidad 331310Republic of Trinidad and Tobago

Local scour around pipelines crossing rivers or in marine environments is a significant *** can lead to failure of the pipelines resulting in environmental side effects and economic *** study developed an experimental method to reduce local scour around pipelines with a steady flow of clear water by installing cylindrical and cubical sacrificial *** sizes of sacrificial piles were examined in a linear *** piles were installed on the upstream side of the pipeline at three *** scour depth reduction rates below the pipeline were *** results showed that sacrificial piles could protect a pipeline from local scour.A portion of scoured sediment around the sacrificial piles was deposited beneath the *** sediment accumulation reduced the scour depth beneath the *** of the experimental results demonstrated that the size of piles(d),the spacing between piles,and the distance between the pipe and piles(Xp)were the variables that reduced the maximum scour beneath the pipeline with a diameter of *** the piles with d=0.40D and 0.64D,X_(p)=4OD was the optimal distance to install a group of piles,and cubical piles could mitigate scour more effectively than cylindrical piles under similar *** the piles with d=D,the greatest reduction in scour depth was achieved at X_(p)=50D with any desired spacings between piles,and cylindrical piles in this dimension could protect the pipeline against scour more effectively than cubical piles.

关键词： Clear water River crossing pipeline Local scour Self-burial process Sediment transport

Development of anti-corrosive coating on AZ31 Mg alloy modified by MOF/LDH/PEO hybrids

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Journal of Magnesium and Alloys 2024年第2期12卷 586-607页

作者： Muhammad ali Khan Ananda Repycha Safira mohammad Aadil Mosab Kaseem Corrosion and Electrochemistry Laboratory Department of Nanotechnology and Advanced Materials EngineeringSejong UniversitySeoul 05006Republic of Korea

The self-assembly of hybrid inorganic-organic materials on stationary platforms plays a critical role in improving their structural stability and wide *** this work,a novel two-step hydrothermal approach is proposed for synthesizing stable and advanced hybrid coatings on metal-oxide platforms through the surface modification of layered double hydroxide(LDH)films using novel metal-organic frameworks(MOFs).Initially,Mg-Al LDH nanocontainers,grown on a magnesium oxide layer produced through plasma electrolytic oxidation(PEO)of AZ31 Mg alloy substrate,were intercalated with cobalt via an oxidation route,providing the metallic coordination center for the MOF *** the subsequent step,a pioneering technique is introduced,utilizing tryptophan as the organic linker for the first time at a pH of *** self-assembly of cobalt-tryptophan complex,driven by the strong bonding between electrophilic sites of monomers and nucleophilic sites,facilitated the formation of a MOF network having a cloud-like structure on the surface of MgAl LDH's *** resulting MOF-LDH encapsulation containers demonstrate exceptional electrochemical stability when exposed to a 3.5 wt.%NaCl solution,surpassing the performance of PEO and pure LDH *** enhanced stability is attributed to the development of a dense top layer and a stable composition within the self-assembled MOF,effectively sealing flaws and preventing the infiltration of corrosive ions into the underlying metallic *** formation mechanism of MOFs on LDH galleries is investigated using density functional theory calculations.

关键词： Mg alloy Layered double hydroxide Metal-organic frameworks Corrosion DFT