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Selective Synthesis of 2-Aryl-l-benzylated-1 h-benzimidazoles

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Chinese Journal of Chemistry 2011年第11期29卷 2389-2393页

作者： Shaterian, hamid reza Fahimi, Nafiseh Azizi, Kobra Department of Chemistry Faculty of Sciences University of Sistan and Baluchestan PO Box 98135-674 Zahedan lran

An efficient and simple procedure was developed for the green synthesis of various 2-aryl-l-ben- zylated-1h-benzimidazoles in high yields by condensation of o-phenylenediamine with aldehydes with P2O5/SiO2 as catalyst... 详细信息

关键词： synthetic methods aldehydes one-pot benzimidazoles heterogeneous catalyst solvent-free

Structural and Mechanical Properties of TiN-TiC-TiO System: First Principle Study

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Communications in Theoretical Physics 2017年第11期67卷 678-686页

作者： Ali reza Farhadizadeh Ahmad Ali Amadeh hamidreza Ghomi School of Metallurgy and Materials Engineering College of Engineering University of Tehran Laser and Plasma Research Institute Shahid Beheshti University

Mechanical and structural properties of ternary system of TiN-TiO-TiC are investigated using first principle methods. 70 different compositions of Ti100(NOC)100 with cubic structure are examined in order to illustrate the trend of properties variations. The geometry of compounds is optimized, and then, their chemical stability is assessed. Afterward,shear, bulk and young moduli, Cauchy pressure, Zener ratio, hardness and h3/E2 ratio are computed based on elastic constants. Graphical ternary diagram is used to represent the trend of such properties when the content of nitrogen,oxygen and carbon varies. The results show that incorporation of oxygen into the system decreases the hardness and h^3/E^2 ratio while subsequently ductility increases due to positive Cauchy pressure. It is revealed that the maximum h^3/E^2 ratio occurs when both nitrogen and carbon with a little amount of oxygen are incorporated. Ti_(100) N_(30) C_(70) owns the highest hardness and h^3/E^2 ratio equal to 39.5 and 0.2 GPa, respectively. In addition, the G/B of this compound,which is about 0.9, shows it is brittle. It is also observed that the solid solutions have better mechanical properties with respect to titanium nitride and titanium carbide. The obtained results could be used to enhance monolayer coatings as well as to design multilayers with specific mechanical properties.

关键词： mechanical properties structural properties first principles calculation elastic constant

Synthesis and Infrared Spectra Computation of Sterically Congested 2,2-Disubstituted Indane-1,3-dione Derivatives

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Chinese Journal of Structural Chemistry 2011年第4期30卷 568-574页

作者： Seyed Mohammad Shoaei Ali reza Kazemizadeh Ali Ramazani Department of Chemistry Islamic Azad UniversityZanjan Branch

Sterically congested 2,2-disubstituted indane-1,3-dione derivatives have been syn-thesized and characterized by 1h NMR,13C NMR,FT-IR and elemental *** B3LYP/hF calculations for computation of IR spectra have been carried out for the title compounds at the 6-31G and 6-311＋＋G basis set *** vibrational frequencies have been assigned and compared with the experimental FT-IR spectra and they are supported each other.

关键词： vibrational frequency DFT hF FT-IR spectra 2 2-disubstituted indane-1 3-dione isocyanide

Effect of milling atmosphere on structural and magnetic properties of Ni-Zn ferrite nanocrystalline

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Chinese Physics B 2015年第4期24卷 481-490页

作者： Abdollah hajalilou Mansor hashim reza Ebrahimi-Kahrizsangi Mohamad Taghi Masoudi Material Synthesis and Characterization Laboratory Institute of Advanced Technology (ITMA)Universiti Putra Malaysia Advanced Materials Research Center Materials Engineering Department Najafabad Branch Islamic Azad University

Powder mixtures of Zn, NiO, and Fe2O3 are mechanically alloyed by high energy ball milling to produce Ni-Zn ferrite with a nominal composition of Ni0.36Zn0.64Fe2O4. The effects of milling atmospheres （argon, air, and oxygen）, milling time （from 0 to 30 h） and heat treatment are studied. The products are characterized using x-ray diffractometry, field emission scanning electron microscopy equipped with energy-dispersive x-ray spectroscopy, and transmitted electron microscopy. The results indicate that the desired ferrite is not produced during the milling in the samples milled under either air or oxygen atmospheres. In those samples milled under argon, however, Zn/NiO/Fe2O3 reacts with a solid-state diffusion mode to produce Ni-Zn ferrite nanocrystalline in a size of 8 nm after 30-h-milling. The average crystallite sizes decrease to 9 nm and 10 nm in 30-h-milling samples under air and oxygen atmospheres, respectively. Annealing the 30-h-milling samples at 600℃ for 2 h leads to the formation of a single phase of Ni-Zn ferrite, an increase of crystallite size, and a reduction of internal lattice strain. Finally, the effects of the milling atmosphere and heating temperature on the magnetic properties of the 30-h-milling samples are investigated.

关键词： Ni-Zn ferrite nanocrystalline mechanical alloying milling atmosphere milling time magnetic property

Manufacturing of cast A356 matrix composite reinforced with nano- to micrometer-sized SiC particles

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Rare Metals 2017年第1期36卷 46-54页

作者： reza Taherzadeh Mousavian Rasoul Azari khosroshahi Sasan Yazdani Dermot Brabazon Faculty of Materials Engineering Sahand University of Technology Tabriz 65175-4171 Iran Advanced Processing Technology Research Centre School of Mechanical and Manufacturing Engineering Dublin City University Dublin 9 Ireland

In this study, large micron-sized Si C particles were fragmented via ball-milling process in the presence of iron and nickel powders, separately, to fabricate composite powders of Fe–Si C and Ni–Si C. Continuous fracturing of brittle Si C powders leads to the formation of multi-modalsized Si C powders with size of from 50 nm to slightly higher than 10 lm after 36-h ball milling. The milled powders were then incorporated into the semisolid melt of A356 aluminum alloy to ease the incorporation of fine Si C particles by using iron and nickel as their carrier *** final as-cast composites were then extruded at 500 °C with a reduction ratio of 9:1. Lower-sized composite powders with slight agglomeration are obtained for the36-h milled Ni–Si C mixture compared to that of Fe–Si C powders, leading to incorporation of Si C particles into the melt with a lower size and suitable distribution for the Ni–Si C mixture. It is found that lower-sized composite particles could release the fine Si C particles into the melt more easily, while large agglomerated composite particles almost remain in its initial form, resulting in sites of stress concentration and low-strength aluminum matrix composites. Ultimate tensile strength(UTS) and yield strength(YS) values of 243 and 135 MPa, respectively, are obtained for the aluminum matrix composite in which nickel acts as the carrier of fine ceramic particles.

关键词： Aluminum matrix composite Semisolid casting Extrusion Ni Fe

Oxidative coupling of methane over (Na_2WO_4+Mn or Ce)/SiO_2 catalysts:In situ measurement of electrical conductivity

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Journal of Natural Gas Chemistry 2010年第1期19卷 35-42页

作者： Zeinab Gholipour Azim Malekzadeh reza hatami Yadollah Mortazavi Abasali khodadadi School of Chemistry Damghan University of Basic Sciences (DUBS) P.O. Box 36715/364 Damghan I. R. Iran Catalysis and Nanostructured Materials Research Laboratory School of Chemical Engineering University of Tehran P.O. Box 11365/4563 Tehran I. R. Iran

The effects of manganese oxide or ceria promoters on the performance of Na2WO4/SiO2 catalysts for oxidative coupling of methane （OCM） are reported. The OCM reaction was performed in a continuous-flow microreactor at 800℃, atmospheric pressure and under GhSV = 13200 ml·gCat^-1·h^-*** were characterized by in situ conductivity measurement, FT-IR spectroscopy, XRD, SEM and temperature programmed reduction analysis. Manganese oxide promoted Na2WO4/SiO2 is considered as one of the active and selective catalysts for OCM reaction. Ceria with high oxygen storage capacity is selected as a proper oxygen activator, providing a higher concentration of the oxy-anion species which is suitable for OCM reaction and compared with manganese oxide. Electrical conductivity of the catalysts was measured in OCM reaction under oxidizing atmosphere, i.e. in the absence of methane. It was found that the trimetallic catalysts, i.e. the catalysts having sodium, tungsten and Mn or Ce species, exhibited similar crystalline structures and morphologies, which lead to suitable bulk properties for the formation of an active and selective catalyst. however, tungsten had significant effect on the texture and redox properties of the catalysts. It was also shown that the crystalline structure of the bimetallic （Na＋Mn or Ce）/SiO2 samples was quite different. This reveals that the metal oxides have significant effect on the extent of crystallization, taking place in the course of interaction of sodium with silica support. Similar conductivities and catalytic performances of （Na2WO4＋Mn or Ce）/SiO2 catalysts propose that the ability of Na2WO4/SiO2 for utilizing oxy-anions formed in presence of different metal oxides is limited.

关键词： oxidative coupling of methane (OCM) conductivity manganese oxide ceria TPR

Inhibiting soil loss and runoff from small plots induced by an individual freeze-thaw cycle using three rangeland species

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International Soil and Water Conservation Research 2020年第3期8卷 228-236页

作者： Milad hatefi Seyed hamidreza Sadeghi reza Erfanzadeh Morteza Behzadfar Department of Watershed Management Engineering Faculty of Natural ResourcesTarbiat Modares UniversityIran Department of Rangeland Management Faculty of Natural ResourcesTarbiat Modares UniversityNoorIran

This study investigated the role of three rangeland species *** trichophorum,Medicago sativa,and Lolium prenne on mitigating of effects of a freeze-thaw(FT)cycle on runoff generation and soil loss from small experimental *** plots(0.5×0.5m)were prepared in three replicates for control(i.e.,under a FT cycle only)and treatments(i.e.,individually planted with the study species and subject to a FT cycle).The treated plots were then placed at a slope of 20%and subjected to simulated rainfall with intensity of 70 mm h-1 and 30 min *** results of the study showed a significant effect(Phe plants on controlling runoff and soil loss after a FT ***,the detrimental effects of the FT cycle due to performance of ice lenses and formation of an active melting layer in the soil surface were ameliorated by the presence of litter on the soil and root-binding effect of the *** to runoff increased by 54,111 and 10%,runoff volume decreased by 27,68 and 0.4%and soil loss changed by-34,-62,and+6.5%in the plots planted with ***,*** and ***,*** results of the current study indicated that *** had the maximum benefit on reducing runoff and soil loss from the plots undergoing a FT cycle.

关键词： Biological measures Frosted soil Plant binding effects Soil hydrology

Cytoreductive surgery and intraperitoneal chemotherapy for colorectal peritoneal metastases

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World Journal of Gastroenterology 2014年第38期20卷 14018-14032页

作者： reza Mirnezami Brendan J Moran Kate harvey Tom Cecil Kandiah Chandrakumaran Norman Carr Faheez Mohamed Alexander h Mirnezami Section of Biosurgery and Surgical Technology Department of Surgery and CancerImperial College London10th Floor QEQM BuildingSt Mary’s Hospital National Pseudomyxoma Peritonei Centre Hampshire Hospitals Foundation Trust Somers Cancer Research Building University of Southampton Cancer Sciences DivisionSouthampton University Hospital NHS Trust

AIM: To systematically review the available evidence regarding cytoreductive surgery (CRS) and intraperitoneal chemotherapy (IPC) for colorectal peritoneal metastases (CPM).

关键词： Colorectal cancer Peritoneal metastasis Cytoreductive surgery Intraperitoneal chemotherapy hyperthermic intraperitoneal chemotherapy

Synthesis and Characterization of Novel Castor Oil-Based Polyol for Potential Applications in Coatings

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Journal of Renewable Materials 2019年第1期7卷 31-40页

作者： Azam Sardari Ali Asghar Sabbagh Alvani Seyed reza Ghaffarian Color&Polymer Research Center(CPRC) Amirkabir University of TechnologyTehran158754413Iran Department of Polymer Engineering and Color Technology Amirkabir University of TechnologyTehran158754413Iran Advanced Materials Group Iranian Color Society(ICS)***TehranIran

In this study,three sorts of polyols were successfully synthesized from castor oil using a Dean-Stark quick,eco-friendly and high-efficiency *** this purpose,castor oil was epoxidized in the presence of two types of catalysts includingγ-alumina and formic acid,named as ECOAl and ECOF,*** castor oils were then characterized by use of hydrogen nuclear magnetic resonance(h-NMR)and oxirane oxygen content *** relative percentages of conversion double bond to oxirane were obtained 96% and 74% for ECOAl and ECOF,*** opening reaction of ECOAl was performed by two types of saponified castor oil as well as castor oil in a system equipped with Dean–Stark *** synthesized polyols were characterized by attenuated total reflectance-Fourier transform infrared spectroscopy(ATR-FTIR),gel permeation chromatography(GPC),differential scanning calorimetry(DSC),viscometer and Oh number *** material obtained in this research is a candidate to be intended in synthesis of polyurethane for coating applications.

关键词： Castor oil dean-Stark polyol epoxidation