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Chinese Journal of Catalysis 2018年第6期39卷 1044-1050页

作者： hojat veisi Ahmad Nikseresht Shahin Mohammadi Saba Hemmati Department of Chemistry Payame Noor UniversityTehran Ira

This paper describes a facile in‐situ synthesis of palladium nanoparticles （Pd NPs） on silica gel/polydopamine composite（SiO2/PDA） without any stabilizer or reducing agent. In this approach, palladium ions were adsorbed on SiO2/PDA surfaces by immersing the PDA‐coated SiO2 particles in a palladium plating bath. Then, they were reduced in situ to Pd nanoclusters by the reducing ability of PDA＇s N‐containing groups. The structure, morphology, and physicochemical properties of the synthesized nanocomposites were characterized by different analytical techniques such as high‐resolution transmission electron microscopy, field‐emission scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, X‐ray diffraction analysis, X‐ray photoelectron spectroscopy, inductively coupled plasma and Fourier‐transform infrared spectroscopy. The Pd NPs capped by the PDA groups had a strikingly small size（30–40 nm）. SiO2/PDA/Pd NPs exhibited high catalytic activ‐ity as a recyclable nanocatalyst in the aerobic oxidation of alcohols. Furthermore, recovery and multiple reuse of the catalyst revealed no detectable activity loss.

关键词： Silica Polydopamine Palladiumnanoparticle OxidationAlcohol

Electro-catalyzed multicomponent transformation of 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one to 1,4-dihydropyrano[2,3-c]pyrazole derivatives in green medium

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Chinese Chemical Letters 2015年第8期26卷 973-976页

作者： Zahra Vafajoo Nourallah Hazeri Malek Taher Maghsoodlou hojat veisi Department of Chemistry Faculty of Sciences University of Sistan and Baluchestan Department of Chemistry Payame Noor University

An efficient and convenient synthesis of 1,4-dihydropyrano[2,3-c]pyrazole derivatives is described,using the electrogenerated anion of ethanol as the base in the presence of sodium bromide as an supporting electrolyte in a one-pot, three component condensation of malononitrile, aromatic aldehydes and 3-methyl-1-phenyl-1H-pyrazol-5（4H）-one. The reaction is carried out in an undivided cell containing an iron electrode as the cathode and a graphite electrode as the anode, at a constant current at room temperature.

关键词： pyrazole catalyzed aldehydes aromatic condensation convenient electrolyte graphite cathode anode

Wet 2,4,6-trichloro-1,3,5-triazine(TCT) as an efficient catalyst for the synthesis of 2,4,6-triarylpyridines under solvent-free conditions

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Chinese Chemical Letters 2010年第11期21卷 1346-1349页

作者： Behrooz Maleki Davood Azarifar hojat veisi Seyede Fatemeh hojati Hafezeh Salehabadi Razieh Nejat Yami Department of Chemistry Sabzevaar Tarbiat Moallem University Department of Chemistry Bu-Ali Sina University Department of Chemistry Payame Noor University

An efficient one-pot synthesis of 2,4,6-triarylpyridines has been *** involves the three-component reaction of aldehydes,ketones and ammonium acetate in the presence of a catalytic amount of wet 2,4,6-trichloro-1,3,5-... 详细信息

关键词： 2 4 6-Triarylpyridines 2 4 6-Trichloro-l 3 5-triazine Aldehydes Ketones Ammonium acetate

Effects of Yttrium Addition on Microstructure, Hardness and Resistance to Wear and Corrosive Wear of TiNi Alloy

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Journal of Materials Science & Technology 2011年第9期27卷 851-855页

作者： hojat Ahmadi Meisam Nouri Faculty of Biosystems Engineering University of Tehran Department of Materials Engineering Tarbiat Modares University

TiNi alloy has a high resistance to wear and could be an excellent candidate for various tribological applications. In this paper, it was demonstrated that by addition of yttrium, hardness properties and resistance to wear and corrosive wear of TiNi alloy were improved. New yttrium rich regions were formed in microstructure of TiNi alloy. The improved properties of this alloy by the yttrium addition could be attributed to the formation of these regions. The results showed that there was an optimum content for addition of yttrium between 2% and 5% （in wt%）, and above this content the improvement in properties of TiNi became minor.

关键词： Yttrium TiNi Mechanical behaviour Wear Corrosive wear Microstructure

The role of geometrical features in the architecturalstructural interaction:Some case studies of the Iranian ancient architecture

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Frontiers of Structural and Civil Engineering 2019年第3期13卷 716-724页

作者： Maryam ZANDIYEHVAKILI Isa hojat Mehdi MAHMUDI Faculty of Architecture and Urban Development Art University of IsfahanIsfahanIran Faculty of Architecture College of Fine ArtsUniversity of TehranTehranIran

This research aims to enhance the interaction between a structure and its architectural *** a qualitative approach,the present work discovers some successfully used geometrical features of the Iranian ancient architecture in terms of the architectural-structural *** define four qualitative criteria for this assessment,i.e.,construction-ability,cost effectiveness,participation of the structure in fulfillment of the visual,and functional-semantic needs of the architectural *** this purpose,two case studies including the Jame Mosque of Isfahan and the Soltaniyeh building are *** outcomes of this research help designers to not only design efficient structures by adapting non-load bearing elements with the general form of the structure,but also meet concepts such as the unity or perfectionism in the structure.

关键词： architectural-structural interaction geometrical features structure architectural form Iranian ancient architecture

Data evaluation of ^(169)Yb-producing reactions by charged particles

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Nuclear Science and Techniques 2010年第2期21卷 110-113页

作者： MAHDI Sadeghi hojat Nadi Agricultural Medical & Industrial Research School Nuclear Science and Technology Research Institute Gohardast Karaj *** Iran Faculty of Engineering Research and Science Campus Islamic Azad University Tehran*** Iran

Excitation functions for 169Yb production on low-medium energy accelerators, i.e. proton on 169Tm and natYb, deuteron on 169Tm, and 4He ion on natEr, were calculated by the ALICE/ASH and TALYS-1.0 codes. The target thickness was predicted by SRIM code. Theoretical integral yield for each reaction was compared with experimental data. The radionuclide purity of 169Yb from the 169Tm(p, n)169Yb reaction was determined, and maximum cross section predicted by the ALICE/ASH and TALYS-1.0 codes was about 182 and 154 mb at 11 and at 9 MeV, respectively.

关键词：数据评价反应带电粒子生产大肠杆菌 SRIM 实验数据加速器

Combined Computational and Experimental Study on the Adsorption and Inhibition Effects of N_2O_2 Schiff Base on the Corrosion of API 5L Grade B Steel in 1 mol/L HCl

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Journal of Materials Science & Technology 2014年第3期30卷 239-252页

作者： hojat Jafari Iman Danaee Hadi Eskandari Mehdi RashvandAvei Abadan Faculty of Petroleum Engineering Petroleum University of Technology Department of Chemistry K.N.Toosi University of Technology

The electrochemical behavior of low carbon steel （API 5L grade B） in 1 mol/L HCI solution with different concentrations of N,Nr-bis（4-formylphenol）-trimethylenediamine Schiff base was studied by electrochemical techniques and density functional theory analysis. The inhibition efficiency was found to increase with increasing inhibitor concentration and decreased with increasing temperature. The high inhibition efficiency was attributed to the blocking of active sites by adsorption of inhibitor molecules on the steel surface. Thermodynamic parameters for the adsorption and activation processes were determined. Galvanostatic polarization data indicated that Schiff base act as a mixed-type inhibitor and the adsorption isotherm obeyed the Langmuir adsorption isotherm. Results obtained from quantum chemical studies show excellent correlations between the quantum chemical parameters and the experimental inhibition efficiencies using density functional theory at the B3LYP/6-31G（d,p） and B3LYP/3-21G basis set levels and ab initio calculations using HF/6-31G（d,p） and HF/3-21G methods.

关键词： Corrosion Inhibitor Impedance Density functional theory Atomic force microscopy

Microscopic and macroscopic atomization characteristics of a pressure-swirl atomizer, injecting a viscous fuel oil

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Chinese Journal of Chemical Engineering 2020年第1期28卷 9-22页

作者： Seyed Mohammad Ali Najafi Pouria Mikaniki hojat Ghassemi School of Mechanical Engineering Iran University of Science and Technology(IUST)P.O.B.16765-163TehranIran

Combustion of heavy fuels is one of the main sources of greenhouse gases, particulate emissions, ashes, NOxand SOx. Gasification is an advanced and environmentally friendly process that generates combustible and clean gas products such as hydrogen. Some entrained flow gasifiers operate with Heavy Fuel Oil(HFO) feedstock. In this application, HFO atomization is very important in determining the performance and efficiency of the *** atomization characteristics of HFO(Mazut) discharging from a pressure-swirl atomizer(PSA) are studied for different pressures difference(Δp) and temperatures in the atmospheric ambient. The investigated parameters include atomizer mass flow rate( _m), discharge coefficient(CD), spray cone angle(θ), breakup length(Lb), the unstable wavelength of undulations on the liquid sheet(λs), global and local SMD(sauter mean diameter) and size distribution of droplets. The characteristics of Mazut sheet breakup are deduced from the shadowgraph technique. The experiments on Mazut film breakup were compared with the predictions obtained from the liquid film breakup model. Validity of the theory for predicting maximum unstable wavelength was investigated for HFO(as a highly viscous liquid). A modification on the formulation of maximum unstable wavelength was presented for HFO. SMD decreases by getting far from the atomizer. The measurement for SMD and θ were compared with the available correlations. The comparisons of the available correlations with the measurements of SMD andθ show a good agreement for Ballester and Varde correlations, respectively. The results show that the experimental sizing data could be presented by Rosin-Rammler distributions very well at different pressure difference and temperatures.

关键词： Gasifier Heavy fuel oil Atomization Pressure-swirl atomizer Mazut Size distribution Wavelength Viscosity

Experimental study of a heavy fuel oil atomization by pressure-swirl injector in the application of entrained flow gasifier

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Chinese Journal of Chemical Engineering 2019年第4期27卷 765-771页

作者： Pouria Mikaniki Seyed Mohammad Ali Najafi hojat Ghassemi School of Mechanical Engineering Iran University of Science and Technology

The available SMD(Sauter mean diameter) correlations on pressure-swirl injectors predict droplet sizing very different from each other, especially for heavy fuels. Also there was a lack in the literature for comparing available correlations. So an experimental study was conducted on a heavy fuel oil(HFO) spray, Mazut 380. A pressure swirl injector was designed and fabricated. The experiments for Mazut at 40℃ and 80℃ were compared with the results for water, including spray half cone angle, breakup length and mean droplet diameter,at different injection pressures. Lower spray angle, higher breakup length and larger droplets were observed for lower injection pressures and higher liquid viscosity. SMD was about 75 μm for water and about 87 μm for Mazut at 80℃. The results for droplet mean diameter were also compared with correlations from previous studies on pressure swirl atomizers. The SMD results show that for water spray, LISA method was in good agreement,also Babu and Ballester correlations were successful when high viscosity fluid was injected.

关键词： Atomization Pressure-swirl injector Mazut Size distribution Fuel Viscosity

The effect of urea pretreatment on the formaldehyde emission and properties of straw particleboard

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Journal of Forestry Research 2012年第3期23卷 497-502页

作者： hojat Hematabadi Rabi Behrooz Department of Wood and Paper Science and Technology College of Natural ResourcesTarbiat Modares UniversityP.O.Box 46414-356NoorIran

For manufacturing low-formaldehyde emission particleboard from wheat straw and urea-formaldehyde （UF） resins using urea treatment for indoor environments, we investigated the influence of urea treatment on the formaldehyde emission, physical and mechanical properties of the manufactured particleboard. Wheat straws were treated at three levels of urea concentration （5%, 10%, 15%） and 95℃ as holding temperature. Wheat straw particleboards were manufactured using hot press at 180℃ and 3 MPa with two types of UF adhesive （UF-45, UF-91）. Then the formaldehyde emission values, physical properties and mechanical properties were considered. The results show that the for- maldehyde emission value was decreased by increasing urea concentration. Furthermore, the results indicate that the specimens under urea treatment have better mechanical and physical properties compared with control specimens. Also specimens under urea treatment at 10% concentration and UF-91 type adhesive have the most optimum physical and mechanical strength.

关键词： formaldehyde emission physical and mechanical properties wheat straw particleboard Urea formaldehyde resin