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Dry reforming reaction over nickel catalysts supported on nanocrystalline calcium aluminates with different CaO/Al_2O_3 ratios

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Journal of Natural gas Chemistry 2012年第2期21卷 178-183页

作者： Atiyeh Ranjbar Mehran rezaei Catalyst and Advanced Materials Research Laboratory Chemical Engineering DepartmentFaculty of Engineering University of Kashan Catalyst and Advanced Materials Research Laboratory Chemical Engineering Department Faculty of Engineering University of Kashan Institute of Nanoscience and Nanotechnology University of Kashan

Nanocrystalline calcium aluminates with different CaO/Al2O3 ratios were prepared by a facile co-precipitation method using Poly（ethylene glycol）-block-poly（propylene glycol）-block-poly（ethylene glycol）（PEg-PPg-PEg, MW： 5800） as a surfactant. They were employed as catalyst support for nickel catalysts in methane reforming with carbon dioxide. The prepared samples were characterized by X-ray diffraction （XRD）, N2 adsorption （BET）, temperature-programmed reduction and oxidation （TPR-TPO）, and scanning electron microscopy （SEM） techniques. Catalysts showed a relatively high catalytic activity and stability. TPR analysis revealed that the catalysts with higher CaO content are more difficult to be reduced. TPO analysis showed that the 5 wt%Ni/CA and 5 wt%Ni/C12A7 catalysts with higher CaO amount were effective against coke deposition.

关键词： calcium aluminate nickel catalyst dry reforming

Ni catalysts supported on nanocrystalline magnesium oxide for syngas production by CO_2 reforming of CH_4

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Journal of Natural gas Chemistry 2011年第2期20卷 198-203页

作者： Fereshteh Meshkani Mehran rezaei Catalyst and Advanced Materials Research Laboratory Chemical Engineering Department Faculty of Engineering University of Kashan Institute of Nanoscience and Nanotechnology University of Kashan

CO2 reforming of methane （CDRM） was carried out over MgO supported Ni catalysts with various Ni loadings. The preparation of MgO supported Ni catalysts via surfactant-assisted precipitation method led to the formation of a nanocrystalline carrier for nickel catalysts. The synthesized samples were characterized by XRD, N2 adsorption-desorption, H2 chemisorption, TPR, TPO and SEM techniques. It was found that the high catalytic activity and stability of the prepared catalysts could be attributable to high dispersion of reduced Ni species and basicity of support surface. In addition, the effect of feed ratio, nickel loading and gHSV on the catalytic performance of CDRM over the catalysts were investigated.

关键词： nanocrystalline MgO nickel catalyst dry reforming syngas

Effect of ECAP consolidation temperature on the microstructure and mechanical properties of Al-Cu-Ti metallic glass reinforced aluminum matrix composite

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Journal of Materials Science & Technology 2017年第9期33卷 1031-1038页

作者： M.R.rezaei S.g.Shabestari S.H.Razavi School of Metallurgy and Materials Engineering Iran University of Science and Technology (IUST) Center of Excellence for High Strength Alloys Technology (CEHSAT) School of Metallurgy and Materials EngineeringIran University of Science and Technology (IUST)

Al;Cu;Ti;metallic glass（AMg） reinforced Al matrix composites were consolidated by equal channel angular pressing（ECAP） process. The effects of ECAP consolidation temperature ranging from room temperature to just below the first crystallization temperature of metallic glass on the consolidation of composites were investigated in terms of the relative densities, structural evolutions and mechanical properties of composites. Some intermetallic compounds included Al;CuTi;, Al;Ti and Al;Cu;precipitated from metallic glass particles at consolidation temperature of 300?C. Consolidation temperature did not affect the matrix grains size of the composite. Quantitative analysis revealed that the distribution of reinforcing particles was considerably dependent on consolidation temperature. Density of the composite was increased by increasing the consolidation temperature to 250?C. The composite consolidated at250?C through ECAP process, exhibited the best combination of yield strength and ductility of 184 MPa and 48%, respectively.

关键词： Al matrix composite(AMC) Equal channel angular pressing(ECAP) Consolidation temperature glass particles

Impact of Rainfall Temporal Heterogeneity on Relationship between Curve Number and Rainfall Depth in the Zagros Mountain Region,Iran

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Journal of Mountain Science 2015年第3期12卷 689-698页

作者： Hassan rezaei-SADR Water Resources Department Nahrab Parseh Consulting Engineers Company

The impact of temporal variation of rainfall on the relationship between rainfall and catchment response is investigated in a catchment with high temporally variable rainfalls and a high percentage of permeable soils in the southwest of ***-nine storm events are classified into two classes, High Temporal heterogeneous(HT) and Low Temporal heterogeneous(LT) events using the variogram technique and the storm events of each class are analyzed to detect the relationship between Curve Number(CN) and rainfall depth. It is found that there is not a similar correlation between CN values and rainfall depths for both temporally variable classes, and hence, two different responses can be observed in the catchment according to rainfall temporal heterogeneities. For HT events, a complacent behavior is detected in which the CNs decline as rainfall depth increases while a different response, violent behavior, is observed for LT events in which the CNs rise and asymptotically approach a constant value with increasing storm size. This considerable difference between CN-P relationships derived from the two temporally variable classes of rainfall is attributed to the provocation of different runoff generation mechanisms, infiltration-excess and saturation-excess caused by rainfall temporal heterogeneities. Moreover, the results support the validity of variogram technique to classify storm events into two LT and HT classes.

关键词： Asymptotic approach Curve Numbermethod Infiltration-excess Rainfall temporalvariation Saturation-excess Variogram technique

High-temperature synthesis of SAPO-34 molecular sieve using a dry gel method

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Particuology 2016年第4期14卷 61-65页

作者： Yazdan rezaei Rouein Halladj Sima Askari Ali Tarjomannejad Tofan rezaei Department of Chemical Engineering Amirkcibir University of Technology (Tehran Polytechnic) P.O. Box 15875-4413 TehranIran Department of Chemical Engineering Science and Research Branch Islamic Azad University P.O. Box 14515. 775 Tehran Iran Department of Chemical Engineering &Petroleum University of Tabriz P.O. Box 51664-16471 Tabriz Iran Chemistry Department Islamic Azad University llam Branch P.O. Box 69319-86447 Ilam Iran

SAPO-34 is one of the main catalysts used in the petrochemical industry. Various effective methods have been developed to synthesize SAPO-34 with optimal size and characteristics for such application, In the present study, SAPO-34 was synthesized using a dry gel method at high temperatures. Morpholine was used as an organic template. The products were characterized by X-ray diffraction, field-emission scan- ning electron microscopy, energy-dispersive X-ray spectroscopy, and gas sorption analysis, The results showed that application of the dry gel method at high temperatures successfully afforded a pure catalyst with high crystallinity, Small particles of less than 500 nm could be obtained within a short reaction time of 30 min.

关键词： SAPO-34 Rapid High temperature Dry gel method Synthesis

Theoretical Study of 13C Chemical Shifts Structures of Some ortho-Substituted 3-Anilino-2-nitrobenzo[b]thiophenes and 2-Anilino-3-nitrobenzo[b]thiophenes and Comparison with Experimental

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Chinese Journal of Chemistry 2011年第2期29卷 237-242页

作者： Mahdi rezaei Sameti Department of Physical Chemistry Faculty of Science Malayer University Malayer 65157 Iran

13C NMR chemical shifts have been calculated for structures of some substituted 3-anilino-2-nitrobenzo- [b]thiophenes （2o） and 2-anilino-3-nitrobenzo[b]thiophenes （3o） derivatives containing OH, NH2, OMe, Me, Et, H, F, Cl and Br. The molecular structures were fully optimized using B3LYP/6-31g（d,p）. The calculation of the 13C shielding tensors employed the gAUSSIAN 03 implementation of the gauge-including atomic orbital （gIAO） and continuous set of gauge transformations （CSgT） by using 6-311 ＋＋g（d,p） basis set at density functional levels of theories （DFT）. The isotropic and the anisotropy parameters of chemical shielding for all compounds are calculated. The predicted 13C chemical shifts are derived from equation δ=σ0＋σ where δ is the chemical shift, σ is the absolute shielding, and σ0 is the absolute shielding of the standard TMS. Excellent linear relationships have been observed between experimental and calculated 13C NMR chemical shifts for all derivatives.

关键词： DPT 13C NMR chemical shifts gIAO/CSgT

Assessment of groundwater potential using multi-criteria decision analysis and geoelectrical surveying

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geo-Spatial Information Science 2022年第4期25卷 600-618页

作者： Marzieh Shabani Zohreh Masoumi Abolfazl rezaei Department of Earth Sciences Institute for Advanced Studies in Basic Sciences(IASBS)ZanjanIran Center for Research in Climate Change and global Warming(CRCC) Institute for Advanced Studies in Basic Sciences(IASBS)ZanjanIran

A precise map of the dispersion of the groundwater potential across each watershed can help decision-makers to exert optimal water management in each *** this research,the potential of groundwater resources in both the Zanjanrood Catchment and the Tarom Region,located in the northwest of Iran,has been *** effective criteria including slope,land-use,drainage density,spring density,lithology,lineament density,and rainfall are *** were first weighted using the Analytical Hierarchical Process(AHP)method and then overlaid by the Technique for Order Preferences by Similarity to Ideal(TOPSIS)***,the spatial zoning map of groundwater potential was obtained in four categories.A sensitivity analysis was performed to determine the influence of each criterion on the obtained *** model was verified using both the spatial distribution of the high-discharged production wells and the geophysical-based geoelectric field *** results indicate that the high-discharged wells(>40 l/s)in both regions are dispersed predominantly in the very good zone and,in several cases,in the good ***,the results from the two-dimensional models of resistivity and induced polarization of geoelectrical field survey are inappropriate agreement with those from the TOPSIS ***,there is no suitable potential zone of groundwater in the surrounding highlands to be used in the future for drinking purposes since the highlands water supply is a strategic supply for *** strategies employed in this study,the results of gIS modeling,and the geoelectrical analysis can be considered for sustainable development of similar arid and semi-arid areas since groundwater is considered as the main supplier of water in such regions.

关键词： Spatial Information System(gIS) Remote Sensing(RS) groundwater potential TOPSIS geoelectrical field survey sustainable development

A Calorimetric Study on the Interaction of Zinc and Cadmium Ions with Jack Bean Urease

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Chinese Journal of Chemistry 2011年第3期29卷 446-450页

作者： rezaei Behbehani, g. Saboury, A. A. Sabbaghy, F. Chemistry Department Faculty of Science Islamic Azad University Takestan Branch Takestan Iran Institute of Biochemistry and Biophysics University ofTehran Tehran Iran Chemistry Department Payame Noor University (PNU) Abhar Iran

A thermodynamic study on the interaction of Jack bean urease, JBU, with Zn2＋ and Cd2＋ ions was studied by isothermal titration calorimetry （ITC） at 290, 300 and 310 K in 30 mmol/L Tris buffer solution, pH 7.0. The heats of JBU＋Zn2＋ and JBU＋Cd2＋ interactions are reported and analyzed in terms of the extended solvation theory. It was indicated that there is a set of 12 identical and non-interacting binding sites for Zn2＋ and Cd2＋ ions. The interactions of Zn2＋ and Cd2＋ ions with JBU are exothermic and both enthalpy and entropy driven. The association equilibrium constants for JBU＋Zn2＋ complexes are 4118.20, 3354.70 and 2790.62 Lomol 1 at 290, 300 and 310 K respectively. The association equilibrium constants for JBU＋Cd2＋ interactions are 2831.6 and 2386.28 Lomol 1 at 300 and 310 K, respectively.

关键词： jack bean urease isothermal titration calorimetry inhibitor zinc

Calculation of Energy and Other Properties of Muonic Helium Atom Using Boundary Conditions of Wave Function

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Communications in Theoretical Physics 2010年第9期54卷 518-520页

作者： B.rezaei Physics Department Razi University

The properties of muonic helium atom （^4He＋2μ-e-） in ground state are considered. In this work, the energy and average distance between particles have been obtained using a wave function, which satisfies boundary conditions. It is shown that the obtained energy are very close to the values calculated by others. But the small differences of the expectation values of r^2n are due to the incorporated boundary conditions in proposed wave function and are expected.

关键词： boundary conditions muonic helium wave function correlation function