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Comparing the deactivation behaviour of Co/CNT and Co/γ-Al_2O_3 nano catalysts in Fischer-Tropsch synthesis

Journal of Natural Gas Chemistry 2012年第5期21卷 605-613页

作者： Ahmad Tavasoli Saba Karimi somayeh Taghavi Zahra Zolfaghari Hamideh Amirfirouzkouhi School of Chemistry College of ScienceUniversity of TehranTehranIran

An extensive study of Fischer-Tropsch （FT） synthesis on cobalt nano particles supported on γ-alumina and carbon nanotubes （CNTs） catalysts is reported.20 wt% of cobalt is loaded on the supports by impregnation *** deactivation of the two catalysts was studied at 220 C,2 MPa and 2.7 L/h feed flow rate using a fixed bed *** calcined fresh and used catalysts were characterized extensively and different sources of catalyst deactivation were *** of cobalt-support mixed oxides in the form of xCoO yAl2O3 and cobalt aluminates formation were the main sources of the Co/γ-Al2O3 catalyst *** sintering and cluster growth of cobalt nano particles are the main sources of the Co/CNTs catalyst *** the case of the Co/γ-Al2O3 catalyst,after 720 h on stream of continuous FT synthesis the average cobalt nano particles diameter increased from 15.9 to 18.4 nm,whereas,under the same reaction conditions the average cobalt nano particles diameter of the Co/CNTs increased from 11.2 to 17.8 ***,the initial FT activity of the Co/CNTs was 26% higher than that of the Co/γ-Al2O3,the FT activity over the Co/CNTs after 720 h on stream decreased by 49% and that over the Co/γ-Al2O3 by 32%.For the Co/γ-Al2O3 catalyst 6.7% of total activity loss and for the Co/CNTs catalyst 11.6% of total activity loss cannot be recovered after regeneration of the catalyst at the same conditions of the first regeneration *** is concluded that using CNTs as cobalt catalyst support is beneficial in carbon utilization as compared to γ-Al2O3 support,but the Co/CNTs catalyst is more susceptible for deactivation.

关键词： Fischer-Tropsch synthesis cobalt carbon nanotube γ-alumina deactivation

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A Local Discontinuous Galerkin Method for Two-Dimensional Time Fractional Diffusion Equations

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Communications on Applied Mathematics and Computation 2020年第4期2卷 689-709页

作者： somayeh Yeganeh Reza Mokhtari Jan SHesthaven Department of Mathematical Sciences Isfahan University of TechnologyIsfahan 84156-83111Iran EPFL-SB-MATHICES-MCSS École Polytechnique Fédéral de Lausanne1015 LausanneSwitzerland

For two-dimensional(2D)time fractional diffusion equations,we construct a numerical method based on a local discontinuous Galerkin(LDG)method in space and a finite differ-ence scheme in *** investigate the numerical stability and convergence of the method for both rectangular and triangular meshes and show that the method is unconditionally *** results indicate the effectiveness and accuracy of the method and con-firm the analysis.

关键词： Two-dimensional(2D)time fractional difusion equation Local discontinuous Galerkin method(LDG) Numerical stability Convergence analysis

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Impacts of the precision agricultural technologies in Iran: An analysis experts’ perception & their determinants

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Information Processing in Agriculture 2018年第1期5卷 173-184页

作者： somayeh Tohidyan Far Kurosh Rezaei-Moghaddam Dept.of Agricultural Extension and Education School of AgricultureShiraz UniversityIran

Nowadays agricultural methods developments that are productively,economically,environmentally and socially sustainable are required *** concept of precision agriculture is becoming an attractive idea for managing natural resources and realizing modern sustainable agricultural *** purpose of this study was to investigate factors influencing impacts of precision agriculture from the viewpoints of Boushehr Province *** research method was a cross sectional survey and multi-stage random sampling was used to collect data from 115 experts in Boushehr *** to the results,experts found underground and surface waters conservation,rural areas development,increase of productivity and increasing income as the most important impacts of precision agricultural ***’attitudes indicate their positive view toward these kinds of *** behavioral attitude has the most effect on impacts.

关键词： Sustainable agriculture Precision agriculture Impact assessment Boushehr Iran

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The Flora of Siahrud-e Rudbar Protected Area,Northern Iran

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植物分类与资源学报 2015年第5期37卷 572-576页

作者： Ataei-e jaliseh somayeh Department of Biology Rasht BranchIslamic Azad University

The vascular flora of the Siahrud-e Rudbar protected area was investigated in the years 2007 and 2008. It is a sylvatic area in the Guilan province with a total area of approximately 28 289 hectares. A total of 711 plant specimens were collected and 616 species,subspecies,and varieties,belonging to 373 genera and 101 families were identified. Of these,14 species( 2. 3%) are endemic to Iran. The documented flora exhibited many typically Hyrcanian species,including Hyrcanian endemics. The global phytogeographical affinities of the species were as follows:Euro-Siberian 21. 2%,Iran-Turanian & Euro-Siberian 16. 8%,Pluriregional 11. 7%,Iran-Turanian 10. 6%,and Cosmopolite 5. 5%.

关键词：竹亚科宁南方竹香竹云南龙竹果实形态

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Folic Acid Functionalized Vertically Aligned Carbon Nanotube (FA-VACNT) Electrodes for Cancer Sensing Applications

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Journal of Materials Science & Technology 2016年第7期32卷 617-625页

作者： somayeh Zanganeh Fatemeh Khodadadei S. Rafizadeh Tafti Mohammad Abdolahad Nano Bio Electronic Devices Lab. School of Electrical and Computer Engineering. University of Tehran. RO. Box 14395/515. Tehran. Iran Nanoelectronic Center of Excellence Thin Film and Nanoelectronic Lab. School of Electrical and Computer Engineering University of Tehran RO. Box 14395/515 Tehran Iran School of Chemical Engineering College of Engineering University of Tehran P.O. Box 11155-4563 Tehran Iran

An electrical cancer biosensor was developed using amine-functionalized vertically aligned carbon nanotubes （VACNTs） conjugated to folic acid （FA） molecules. Specific binding of FA to folate receptor （FR） existing on the membrane of cancer cells assisted their entrapment on VACNTs. For the conjugation of FA to CNTs, amine （--NH2） functional groups were attached to the side walls of the nanotubes by plasma treatment. The amount and shape of entrapped cancer cells on FA-VACNTs were noticeably higher and more uniform than the cells entrapped on bare VACNTs. The comparative signal spike of the FA-VACNTs and VACNTs covered impedance sensor in interaction with the same concentration of lung cancer cells （QUDB） showed sharper response for the functionalized sensor. Moreover, electron microscopy and florescent images as well as impedance diagrams verified the spherical and non-deformed shape of the cells entrapped by FA-VACNT, This sensor would be useful in assaying the cells vitality in time evolution. This device could be applied in diagnostic and time monitoring applications in the field of cancer such as extreme drug resistance assay （EDR）.

关键词： Carbon nanotubeImpedance biosensorFolic acidCancer ceil detectionFunctionalization

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Effects of probiotic supplementation on abdominal pain severity in pediatric patients with irritable bowel syndrome:a systematic review and meta-analysis of randomized clinical trials

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World Journal of Pediatrics 2022年第5期18卷 320-332页

作者： somayeh Fatahi Amirhossein Hosseini Mohammad Hassan Sohouli Aliakbar Sayyari Katayoun Khatami Zahra Fazeli Farsani Hamzeh Amiri Naghi Dara Ivan G.O.de Souza Heitor O.Santos Pediatric Gastroenterology Hepatologyand Nutrition Research Center.Research Institute for Children's HealthShahid Beheshti University of Medical SciencesTehranIran Student Research Committee Faculty of Public Health BranchIran University of Medical Sciences.Tehran.Iran Student Research Committee.Department of Clinical Nutrition and Dietetics Faculty of Nutrition and Food TechnologyShahid Beheshti University of Medical Sciences.TehranIran School of Health Sciences.Universidade Salvador(UNIFACS) SalvadorBahia.Brazil School of Medicine Federal University of Uberlandia(UFU)UberlandiaMinas GeraisBrazil

Background Probiotic supplementation has been used to alleviate abdominal pain in children and adolescents with irritable bowel syndrome(IBS),but the evidence is not ***,a systematic review and meta-analysis of randomized clinical trials(RCTs)were performed to investigate the effects of probiotic supplementation on abdominal pain in pediatric patients with *** PubMed/MEDLINE,Web of Science,Scopus,Cochrane Library,and Embase were the available databases searched to find relevant randomized clinical trials up to April *** effect size was expressed as weighted mean differenee(WMD)and 95% confidence interval(CI).Results Seven RCTs with 441 participants were included,from which the meta-analysis demonstrated that probiotic supplementation has a significant effect on reducing abdominal pain in pediatric patients with IBS(WMD=-2.36:95%CI-4.12 to-0.60;P=0.009).Although our study involved children and adolescents(≤18 years),the effects of probiotic supplementation seem to be more potent in patients under 10 years old(WMD=-2.55;95%CI-2.84 to -2.27)compared to patients aged 10-18 years(WMD=-1.70;95%CI-2.18 to -1.22).The length of supplementation longer than four weeks was more effective(WMD=-2.43;95%CI-2.76 to -2.09).Conclusion Probiotic supplementation can reduce abdominal pain in pediatric patients with IBS.

关键词： Abdominal pain Adolescents-Irritable bowel syndrome Meta-analysis Probiotic

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Mapping desertification potential using life cycle assessment method: a case study in Lorestan Province, Iran

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Journal of Arid Land 2019年第5期11卷 652-663页

作者： Abolfazl RANJBAR somayeh HEYDARNEJAD Sayed H MOUSAVI Roohallah MIRZAEI Department of Desert Studies University of KashanKashan ***Iran Department of Geography and Ecotourism University of KashanKashan ***Iran Department of Environmental Sciences University of KashanKashan ***Iran

In recent year,desertification has become one of the most important environmental hazards all over the world,especially in developing countries such as *** the factors impacting on desertification and identifying the regions with high desertification potential are essential to control this phenomenon(i.e.,desertification).The life cycle assessment(LCA)method is essential in assessing the desertification of ecosystems,especially for susceptible ecosystems with high degradation *** aim of the present study was to evaluate the desertification potential of Lorestan Province,Iran,based on the LCA *** selected aridity,fire and dust as three indicators of desertification and collected data from 2000 to *** divided the study area into 6 types of ecoregions according to the climate types(arid,semi-arid and dry sub-humid)and dominant species(Quercus brantii and Astragalus adscendens),and calculated the characteristic factor(CF)of each indicator(aridity,fire and dust)by combining the indicator layers and ecoregion layer of the study *** a given ecoregion,the sum of CF values of aridity,dust and fire indicators represents the life cycle inventory(LCI)desertification value(the higher the LCI value,the greater the desertification potential).Then,we obtained the desertification potential map by combining and overlapping the ecoregions and the normalized indicators based on the LCA *** and fire exhibit significant impacts on desertification in the study area compared with *** the study area,semi-arid ecoregion with Quercus brantii as the dominant species is the largest ecoregion,while arid ecoregion with Quercus brantii as the dominant species is the smallest *** ecoregion with Astragalus adscendens as the dominant species(LCI desertification value of 1.99)and dry sub-humid ecoregion with Quercus brantii as the dominant species(LCI desertification value of 0.79)show the highest and lowest desertification potentials,respec

关键词： life cycle assessment characterization factor desertification potential aridity index fire risk dusty days Lorestan Province

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Molecular approach to determine taxonomic status of Septoria *** leaf blotch of Castanea sativa in Hyrcanian forests

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Journal of Forestry Research 2017年第4期28卷 661-670页

作者： Hamed Yousefzadeh Abbas Saidi somayeh Tayebi Davoud Kartoolinejad Reza Naghdi Department of Forestry Faculty of Natural ResourcesTarbiat Modares UniversityTehranIran Biotechnology Department Faculty of Energy Engineering and New TechnologyShahid Beheshti UniversityTehranIran Department of Arid Land Forestry Faculty of Desert StudiesSemnan UniversitySemnan 35196-45399Iran Department of Engineering of Wood and Paper Industries Faculty of Natural ResourcesSemnan UniversitySemnanIran

Castanea sativa is a valuable tree species in Hyrcanian forests, an evolutionary relict ecosystem whose communities suffer from overexploitation and fungal diseases. In the current study, three species delimitation methods were utilized with ITS regions sequencing to determine the taxonomic status of Septoria causing leaf blotch of C. sativa in Hyrcanian forests. The results indicated that the length of ITS region in the genus Septoria (extracted from GenBank) varied from 650 to 680 bp. There were almost three times more variable sites in ITS1 than in ITS2. The ITS2 secondary structure of Hyrcanian Septoria community had the highest similarity with Septoria castaneicola, except for some differences in helix II and III. Also, Hyrcanian samples had minimum genetic distances with S. castaneicola and maximum with Septoria quercicola. The maximum parsimony method divided the studied Septoria genus into three distinct clades, mostly located in clade I. Clade II consisted entirely of Septoria aciculosa, while clade III contained S. castaneicola as well as Hyrcanian samples.

关键词： Septoria castaneicola Hyrcanian forests ITS secondary structure Forest pathogen Plylogeny of fungi Sweet chestnut Fagaceae

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Hepatitis C virus core protein modulates several signaling pathways involved in hepatocellular carcinoma

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World Journal of Gastroenterology 2019年第1期25卷 42-58页

作者： Shahab Mahmoudvand somayeh Shokri Reza Taherkhani Fatemeh Farshadpour Department of Virology School of Medicine Ahvaz Jundishapur University of Medical Sciences Department of Medical Virology School of MedicineHamadan University of Medical Sciences The Persian Gulf Tropical Medicine Research Center Bushehr University of Medical Sciences

Hepatocellular carcinoma(HCC) is the fifth most common cancer, and hepatitis C virus(HCV) infection plays a major role in HCC development. The molecular mechanisms by which HCV infection leads to HCC are varied. HCV core protein is an important risk factor in HCV-associated liver pathogenesis and can modulate several signaling pathways involved in cell cycle regulation, cell growth promotion, cell proliferation, apoptosis, oxidative stress and lipid metabolism. The dysregulation of signaling pathways such as transforming growth factor β(TGF-β), vascular endothelial growth factor(VEGF), Wnt/β-catenin(WNT), cyclooxygenase-2(COX-2) and peroxisome proliferator-activated receptor α(PPARα) by HCV core protein is implicated in the development of HCC. Therefore, it has been suggested that this protein be considered a favorable target for further studies in the development of HCC. In addition, considering the axial role of these signaling pathways in HCC, they are considered druggable targets for cancer therapy. Therefore, using strategies to limit the dysregulation effects of core protein on these signaling pathways seems necessary to prevent HCV-related HCC.

关键词： Hepatitis C virus Core protein Transforming growth factorβ Vascular endothelial growth factor Wnt/β-catenin Cyclooxygenase-2 Peroxisome proliferatoractivated receptorα Hepatocellular carcinoma

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Sensing behavior of BN nanosheet toward nitrous oxide: A DFT study

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Chinese Chemical Letters 2015年第8期26卷 1042-1045页

作者： Marjaneh Samadizadeh Ali Ahmadi Peyghan somayeh F.Rastegar Department of Chemistry Islamic Azad University Central Tehran Branch Young Researchers and Elite Club Central Tehran Branch Islamic Azad University

In order to develop a sensor for the detection of toxic N2O molecules, the interaction of pristine and Aldoped BN nanosheets with an N2O molecule was investigated using density functional theory calculations. It was found that unlike the pristine sheet, the Al-doped sheet can effectively interact with the N2O molecule so that its electronic properties and conductivity are dramatically changed. We believe that replacing a B atom of the BN sheet with an Al atom may be a good strategy for improving the sensitivity of these nanosheets toward N2O, which cannot be trapped and detected by the pristine sheet.

关键词： toward sheet trapped reserved unlike interact dramatically doping Wales adsorbed

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