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Synthesis of a nitrogen-doped titanium dioxide-reduced graphene oxide nanocomposite for photocatalysis under visible light irradiation

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Particuology 2018年第6期16卷 48-57页

作者： Ehsan Vahidzadeh Shohreh fatemi Amideddin Nouralishahi School of Chemical Engineenng College of EngineeringUniversity of TehranP.O.Box 11365-4563TehranIran Caspian Faculty of Engineering College of EngineeringUniversity of TehranP.O.Box 11365-4563TehranIran

A nitrogen-doped titanium dioxide-reduced graphene oxide (N-TiO2-rGO)nanocomposite has been synthesized by the combination of a hydrothermal method and a thermal treatment under a NH3/N2 *** resulting composites are characterized by Fourier transform infrared spectroscopy, scanning electron microscopy,transmission electron microscopy,diffuse reflectance absorption spectroscopy,energy-dispersive X-ray spectroscopy,and raman characterization *** sequence of the thermal treatment and hydrothermal treatment processes is shown to influence the photocatalytic activity of nitrogen-doped *** composites synthesized by using this method show better photocatalytic activities toward the degradation of acetaldehyde under visible light irradiation compared with P25,N-TiO2,and *** applying the thermal treatment process after the hydrothermal pro- cess,nitrogen atoms can be simultaneously doped in the lattice ofTiO2nanoparticles and on the surface of reduced graphene oxide *** conversion of acetaldehyde,as the model molecule of volatile organic compounds,is measured in a continuous stirred-tank reactor until the steady state condition is reached. The conversion of 50 ppm acetaldehyde,in an air flow under illumination from an 80W Hg lamp with a UV cut-off filter,reaches 62% after a 1-h reaction using a 0.07g N-TiO2-rGO sample with an optimum loading of 2wt% graphene *** comparison,the photocatalytic activity of P25 for the degradation of acetaldehyde under visible light irradiation is only 8% under the same reaction *** reaction rates for acetaldehyde degradation are calculated and predicted with pseudo-first-order reaction kinetics,and the activity result of the best N-TiO2-rGO sample is 12.3times higher than for P25.

关键词： N-doped TiO2 Photocatalyst reduced graphene oxide Visible light irradiatlon Nanocomposite Nanoparticle

High photocatalytic efficiency of spouting reactor compared with fluidized bed with top irradiation source

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Particuology 2017年第4期15卷 123-128页

作者： Hadi Mansoubi Zahra Mansourpour Shohreh fatemi School of Chemical Engineering College of Engineering University of Tehran Tehran lran

The removal of volatile organic compounds by photocatalytic degradation is one of the safest and most effective ways of removing pollutants from the air. This process is highly affected by the type of reactor, light exposure, and hydrodynamics. For scale up purposes, continuous reactors with high capacity are required for treating large amounts of feedstock. In this work, two types of reactors based on different hydrodynamics, fluidized and spouted reactors, were designed to work under light irradiation inside the reactor. The efficiency of the reactors for volatile organic compound removal from high flow rates of air under Hg lamp irradiation using N-F-TiO2 photocatalyst was investigated. The performance of the fluidized bed and spouted bed were evaluated and compared at the same weight hourly space velocity of feed stream through the reactor. The results revealed that 80% of the initial acetaldehyde was removed in the fluidized bed after about 200 min, while in the spouted bed the acetaldehyde was totally removed after about 120 min.

关键词： Spouted bed reactor Photocatalyst powder VOC removal High efficiency Fluidized bed reactor N-F TiO2

Synthesis and stability evaluation of hierarchical silicoaluminophosphates with different structural frameworks in the methanol to olefins process

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Particuology 2018年第2期16卷 43-53页

作者： Seyed Hesam Mousavi Shohreh fatemi Marian razavian School of Chemical Engineering College of Engineering University of Tehran P.O. Box 11365 4563 TehranIran

Silicoaluminophosphates （SAPOs） with different pore structures were synthesized through the implementation of polyethylene glycol （PEG） as a mesopores impregnation agent. Using PEGs with different molecular weights （MWs） and concentrations in the synthesis precursor, several samples were synthesized and characterized. Applying a PEG capping agent to the precursors led to the formation of tuned mesopores within the microporous matrix of the SAPO. The effects of the PEG molecular weight and PEG/Al molar ratio were investigated to maximize the efficiency of the catalyst in the methanol-to-olefin （MTO） process. Using PEG with a MW of 6000 resulted in the formation of both Zeolite rho and chabazite structural frameworks （i.e., DNL-6 and SAPO-34）. Pure SAPO-34 samples were successfully prepared using PEG with a MW of 4000. Our results showed that the PEG concentrations affect the porosity and acidity of the synthesized materials. Furthermore, the SAPO-34 sample synthesized with PEG （MW of 4000） and a PEG/Al molar ratio of 0.0125 showed a superior catalytic stability in the MTO reaction owing to the tuned bi-modal porosity and tailored acidity pattern. Finally, through reactivation experiments, it was found that the catalyst is stable even after several regeneration cycles.

关键词： Hierarchical SAPO-34 PEG Mesoporosity DNL-6 zeolite MTO process Catalytic stability

Selective nitration of phenols using bismuth subnitrate/charcoal in the presence of trichloroisocyanuric acid under aprotic conditions

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Chinese Chemical Letters 2010年第11期21卷 1283-1286页

作者： Ali reza Pourali Fatemeh fatemi School of Chemistry Damghan University of Basic Sciences

A mild,efficient and regioselective method for the mononitration of phenolic compounds is described using bismuth subnitrate/ charcoal in the presence of trichloroisocyanuric acid in CH2Cl2 at room temperature.

关键词： Nitration Phenol Bismuth subnitrate Supported reagent

A multi-layered policy generation and management engine for semantic policy mapping in clouds

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Digital Communications and Networks 2020年第1期6卷 38-50页

作者： Faraz fatemi Moghaddam Philipp Wieder ramin Yahyapour Gesellschaft für wissenschaftliche Datenverarbeitung mbH Gottingen(GWDG) Germany Institute of Informatics Georg-August-UniversitatGottingenGermany

The long awaited cloud computing concept is a reality now due to the transformation of computer ***,security challenges have become the biggest obstacles for the advancement of this emerging technology.A well-established policy framework is defined in this paper to generate security policies which are compliant to requirements and ***,a federated policy management schema is introduced based on the policy definition framework and a multi-level policy application to create and manage virtual clusters with identical or common security *** proposed model consists in the design of a well-established ontology according to security mechanisms,a procedure which classifies nodes with common policies into virtual clusters,a policy engine to enhance the process of mapping requests to a specific node as well as an associated cluster and matchmaker engine to eliminate inessential mapping *** suggested model has been evaluated according to performance and security parameters to prove the efficiency and reliability of this multilayered engine in cloud computing environments during policy definition,application and mapping procedures.

关键词： Cloud computing Security Security management Policy management Access control Policy mapping

Measurements of dihadron correlations relative to the event plane in Au+Au collisions at√^(S)NN=200 GeV

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Chinese Physics C 2021年第4期45卷 198-241页

作者： H.Agakishiev M.M.Aggarwal Z.Ahammed A.V.Alakhverdyants I.Alekseev J.Alford B.D.Anderson C.D.Anson D.Arkhipkin G.S.Averichev J.Balewski D.r.Beavis N.K.Behera r.Bellwied M.J.Betancourt r.r.Betts A.Bhasin A.K.Bhat H.Bichsel J.Bieleik J.Bielcikova B.Biritz L.C.Bland W.Borowski J.Bouchet E.Braidot A.V.Brandin A.Bridgeman S.G.Brovko E.Bruna S.Bueltmann I.Bunzarov T.P.Burton X.Z.Cai H.Caines M.Calderon de la Barca Sanchez D.Cebra r.Cendejas M.C.Cervantes Z.Chajecki P.Chaloupka S.Chattopadhyay H.F.Chen J.H.Chen J.Y.Chen L.Chen J.Cheng M.Cherney A.Chikanian K.E.Choi W.Christie P.Chung M.J.M.Codrington r.Corliss J.G.Cramer H.J.Crawford S.Dash A.Davila Leyva L.C.De Silvat r.r.Debbe T.G.Dedovich A.A.Derevschikov r.Derradi de Souza L.Didenko P.Djawotho S.M.Dogra X.Dong J.L.Drachenberg J.E.Draper J.C.Dunlop L.G Efimov M.Elnim J.Engelage G Eppley M.Estienne L.Eun O.Evdokimov r.fatemi J.Fedorisin A.Feng r.G.Fersch P.Filip E.Finch V.Fine Y.Fisyak C.A.Gagliardi D.r.Gangadharan A.Geromitsos F.Geurts P.Ghosh Y.N.Gorbunov A.Gordon O.Grebenyuk D.Grosnick S.M.Guertin A.Gupta W.Guryn B.Haag O.Hajkova A.Hamed L-X.Han J.W.Harris J.P.Hays-Wehle M.Heinz S.Heppelmann A.Hirsch E.Hjort G.W.Hoffmann D.J.Hofiman B.Huang H.Z.Huang T.J.Humanic L.Huo G.Igo P.Jacobs W.W.Jacobs C.Jena F.Jin J.Joseph E.G.Judd S.Kabana K.Kang J.Kapitan K.Kauder H.Ke D.Keane A.Kechechyan D.Kettler D.P.Kikola J.Kiryluk A.Kisiel V.Kizka A.G.Knospe D.D.Koetke T.Kollegger J.Konzer I.Koralt L.Koroleva W.Korsch L.Kotchenda V.Kouchpil P.Kravtsov K.Krueger M.Krus L.Kumar P.Kurnadi M.A.C.Lamont J.M.Landgraf S.LaPointe J.Lauret A.Lebedev r.Lednicky J.H.Lee W.Leight M.J.LeVine C.Lil L.Li N.Li W.Li X.Li X.Li Y.Li Z.M.Li M.A.Lisa F.Liu H.Liu J.Liu T.Ljubicic W.J.Llope r.S.Longacre W.A.Love Y.Lu E.V.Lukashov X.Luo G.L.Ma Y.G.Mai D.P.Mahapatra r.Majka O.I.Mall L.K.Mangotra r.Manweiler S.Margetis C.Markert H.Masui H.S.Matis Yu.A.Matulenko D.MeDonald T.S.McShane A.Meschanin r.Milner N.G.Minaev S.Mioduszewski A.Mischke M.K.Mitrovski B.Mohanty M.M.Mondal B.Morozov D.A.Morozov M.G.Munhoz M Argonne National Laboratory Argonnellinois 60439USA Brookhaven National Laboratory UptonNew York 11973USA University of Califomia BerkeleyCaliformnia 94720USA University of California DavisCalifornia 95616USA University of Califormnia Los AngelesCalifomia 90095USA Universidade Estadual de Campinas Sao PauloBrazil University of Illinois at Chicago ChicagoIlinois 60607USA Creighton University OmahaNebraska 68178USA Czech Technical University in Prague FNSPEPrague11519Czech Republic Nuclear Physics Institute AS Cr 25068 Rez/PragueCzech Republic University of Frankfurt FrankfurtGermany Institute of Physics Bhubaneswar 751005India Indian Institute of Technology MumbaiIndia Indiana University BloomingtonIndiana 47408USA Alikhanov Instiute for Theoretical and Experimental Physics MoscowRussia University of Jammu Jammu 180001India Joint Institute for Nuclear research Dubna141980Russia Kent State University KentOhio 44242USA University of Kentucky LexingtonKentucky40506-0055USA Institute of Modern Physics LanzhouChina Lawrence Berkeley National Laboratory BerkeleyCalifornia 94720USA Massachusetts Institute of Technology CambridgeMA 02139-4307USA Mx-Planck-Institut fir Physik MunichGermany Michigan State University East LansingMichigan 48824USA Moscow Engineering Physics Institute Moscow Russia NIKHEF and Utrecht University AmsterdamThe Netherlands Ohio State University ColumbusOhio 43210USA Old Dominion University NorfolkVA23529USA Panjab University Chandigarh 160014India PennsyIvania State University University ParkPennsylvania 16802USA Institute of High Energy Physics ProtvinoRussia Purdue University West LafayetteIndiana 47907USA Pusan National University PusanRepublic of Korea University of rajasthan Jaipur 302004India rice University HoustonTexas 77251USA Universidade de Sao Paulo Sao PauloBrazil University of Science&Technology of China Hefei 230026.China Shandong University JinanShandong 250100China Shanghai Institute of Applied Physics Shanghai 201800Chi

Dihadron azimuthal correlations containing a high transverse momentum(pr)trigger particle are sensit-ive to the properties of the nuclear medium created at rHIC through the strong interactions occurring between the traversing parton and the medium,*** measurements revealed a strong modification to di-hadron azimuthal correlations in Au+Au collisions with respect to ptp and d+Au *** modification in-creases with the collision centrality,suggesting a path-length or energy density dependence to the je-quenching *** paper reports STAr measurements of dihadron azimuthal correlations in mid-central(20%-60%)Au+Au collisions at√^(S)NN=200 GeV as a function of the trigger particle's azimuthal angle relative to the event plane,Ф_(s)=|Ф_(t)-ψ_(Ep)|.The azimuthal correlation is studied as a function of both the trigger and associated particle *** subtractions of the combinatorial background and anisotropic flow,assuming Zero Yield At Minimum(ZYAM),are *** correlation results are first discussed with subtraction of the even harmonic(elliptic and quadrangu-lar)flow *** away-side correlation is strongly modifed,and the modification varies withФ_(s),with a double-peak structure for out-of-plane trigger *** near-side ridge(long range pseudo-rapidity△_(η)correla-tion)appears to drop with increasingФ_(s)while the jet-like component remains approximately *** correla-tion functions are further studied with the subtraction of odd harmonic triangular flow background arising from *** is found that the triangular flow,while responsible for the majority of the amplitudes,is not sufficient to explain theφs-dependence of the ridge or the away-side double-peak *** dropping ridge withФ_(s)could be attributed to aФ_(s)-dependent lliptie anisotropy;however,the physics mechanism of the ridge remains an open *** with aФ_(s)-dependent elliptic flow,the away-side correlation structure

关键词： relativistic heavy ion collisions dihadron correlations jet-medium interactions anisotropic flow background event plane

Anisotropy in dynamic recrystallization behavior of AZ31 magnesium alloy

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Journal of Magnesium and Alloys 2022年第12期10卷 3470-3484页

作者： S.M.fatemi S.Kheyrabadi H.Paul Department of Metallurgy and Materials Engineering Shahid Rajaee Teacher Training University136-16785 TehranIran Institute of Metallurgy and Materials Science Polish Academy of Sciences(PAS)25 Reymonta Street30-059 KrakowPoland

Deformation behavior as well as microstructural evolutions of a rolled AZ31 magnesium alloy with and without pre-existing extension twins were studied using compression tests which performed along different orientations at a temperature range of 25–350 ℃. The results implied that the initial texture not only influence the evolution of flow stress, but also change the size and fraction of recrystallized *** contrast to samples parallel to rolling and transverse directions, compression along normal direction resulted in a respectful softening at 150 ℃. The largest size and fraction of new grains at 250 ℃ were recorded after deformation along rolling direction, while the maximum flow softening was observed during deformation along normal direction. The anisotropy in microstructural evolutions was still retained at 350 ℃. Pre-existing twins could reduce the anisotropy of material in respect of flow stress as well as DrX progression, where TD sample showed the lowest DrX fraction at 250 ℃. Quaternion misorientation data obtained from EBSD analysis of pretwinned material implied that initial texture could not significantly influence final texture. A different misorientation distribution was realized after deformation of pretwinned material along ND and rD directions.

关键词： Slip recrystallization Grain size Growth Twin

An outlook on coronavirus disease 2019 detection methods

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Journal of Pharmaceutical Analysis 2022年第2期12卷 205-214页

作者： Zahra Hassani Nejad Fataneh fatemi Seyed Ehsan ranaei Siadat Department of Biochemistry Institute of Biochemistry and BiophysicsUniversity of TehranTehran***Iran Department of Protein research Protein Research CenterShahid Beheshti UniversityTehran***Iran Sobhan recombinant Protein Company Research and Development DepartmentTehran***Iran

Diagnostic testing plays a fundamental role in the mitigation and containment of coronavirus disease 2019(COVID-19),as it enables immediate quarantine of those who are infected and contagious and is essential for the epidemiological characterization of the virus and estimating the number of infected cases *** of viral infections,such as COVID-19,can be achieved through two general approaches:nucleic acid amplification tests(NAATs)or molecular tests,and serological or antibody-based *** genetic material of the pathogen is detected in NAAT,and in serological tests,host antibodies produced in response to the pathogen are *** methods of diagnosing COVID-19 include radiological imaging of the lungs and in vitro detection of viral *** review covers different approaches available to diagnosing COVID-19 by outlining their advantages and shortcomings,as well as appropriate indications for more accurate testing.

关键词： COVID-19 Diagnostics Nucleic acid amplification tests Serological tests

Characterization of semisolid deformation behavior of a high Zr-containing WE magnesium alloy

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rare Metals 2022年第12期41卷 4201-4208页

作者： Masoud Moradjoy-Hamedani Abbas Zarei-Hanzaki Seyed Mahmood fatemi School of Metallurgy and Materials Engineering College of EngineeringUniversity of TehranTehran 515-14395Iran School of Mechanical Engineering Shahid Rajaee Teacher Training UniversityTehran 136-16785Iran

The effects of temperature and strain rate on the semisolid deformation behavior of a high Zr WE54 magnesium alloys were studied at temperatures of 570,595 and 620℃.A flow stress peak was appeared during deformation of the feedstock experimental material at deformation conditions of 570℃,0.010 and 0.100 s-1,and 595℃,0.100 *** latter results were connected to the occurrence of dynamic recrystallization in solid ***,these conditions were gauged to be able to activate"lubricated flow"*** 570℃and strain rate of 0.001 s-1as well as 595℃and rates of 0.010 and 0.001 s^(-1),the flow stress increases and reaches a plateau,where dynamic recovery is considered as the dominant ***,at 620℃under all the strain rates,the flow stress drops for a limited strain range and then increases *** results show that as the liquid removes from the boundaries between the solid parts,the densification of the globules occurs at higher strains,causing an increase in the flow *** analysis points out that the feedstock material exhibits a lower flow stress than as-cast alloy associating with a modified morphology of Zr particles after deformation.

关键词： Mg-rE alloy Feedstock Semisolid deformation Liquid flow