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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

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

Kinetics of Soil Potassium Release Under Long-Term Imbalanced Fertilization in Calcareous Soils

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Pedosphere 2017年第6期27卷 1105-1115页

作者： Akram fatemi Soil Science Department Razi UniversityKermanshah ***(Iran)

Knowledge on potassium ion(K^+) release from soils makes K fertilizer recommendation more efficient and *** of K^+release under continuous fertilization of no fertilizer(CK), urea(N), triple superphosphate(P), and urea + triple superphosphate(NP) without K fertilizer was investigated in calcareous(chloritic and kaolinitic) soils on the Miandarband Plain in Kermanshah Province of *** results showed that the kinetics of K^+release included an initial reaction and a slow *** phosphateand NH_4^+-induced K^+release followed the same rate process during the rapid(2–192 h) and slow release periods(192–1 090 h).There were no significant differences in the cumulative K^+released from the chloritic and kaolinitic soils among all the *** cumulative K^+released was positively correlated with P adsorption capacity for the chloritic(r = 0.461, P N = CK for the chloritic soils, and N =P > NP > CK for the kaolinitic *** study showed that K fixation potential and P adsorption capacities controlled K^+release from *** information will be helpful for precise fertilizer recommendations for the studied soils.

关键词： clay mineralogy initial release rate index K fixation potential P adsorption capacity triple superphosphate urea

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

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

Combination of thrombolytic therapy and angioplastic stent insertion in a patient with Budd-Chiari syndrome

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World Journal of Gastroenterology 2007年第27期13卷 3767-3769页

作者： fatemi Reza Daryani E Naser Ganaati Hossein Zahmatkesh Mehrdad Gastrointestinal & Liver Diseases Research Center Semnan University of Medical Sciences 17~(th) Shahrivar Ave. Semnan Iran

A 31-year-old female who had well-established polycythemia vera one year before, presented with the sudden onset. She had severe ascites and hepatic encephalopathy 12 d prior to admission. Real-time ultrasonography revealed a supra hepatic thrombosis extending toward the inferior vena cava （IVC）. Thrombolytic therapy with systemic streptokinase （250000 IU loading ＋ 100000 IU/h infusion） was started. At the end of 72 h infusion, the patient＇s general condition improved. A color Doppler ultrasonography then showed complete and partial resolution of the thrombosis in the supra hepatic vein and IVC, respectively. Despite this good response, 12 d later, the symptoms recurred. Venography detected complete obstruction of the IVC. Percutanous balloon angioplasty with stent insertion was performed successfully and the patient was discharged without any evidence of liver disease. A combination of systemic streptokinase and radiological intervention was effective in our patient.

关键词： Hepatic vein thrombosis Anticoagulants Thrombolytic therapy Stents

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