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41.
Oxidation of methanol to formaldehyde, using a mixture of ferric and molybdenum oxides as catalyst, has been studied in a fixed bed integral reactor, 150 mm long, 25 mm o.d. and 10 mm i.d. The catalyst was prepared by reaction between aqueous solutions of ammonium heptamolybdate and ferric chloride. It has been shown that, under experimental conditions similar to those employed in industry, neither external nor internal diffusion had been effective in the process and isothermal conditions prevailed in both gas and solid phases. A two-step mechanism has been put forward for the oxidation of methanol. According to such a mechanism, methanol is first oxidized to formaldehyde, accepting an oxygen molecule from the catalyst and changing the latter into a reduced form. In the second step, the reduced catalyst is transformed into the original form on obtaining an oxygen molecule from the gas phase. Based on this scheme, a rate model has been derived and verified by experimental results. 相似文献
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H Gao J Arrington EJ Beise B Bray RW Carr BW Filippone A Lung RD McKeown B Mueller ML Pitt CE Jones D DeSchepper G Dodson K Dow R Ent M Farkhondeh J Hansen W Korsch LH Kramer K Lee N Makins RG Milner DR Tieger TP Welch E Candell J Napolitano BB Wojtsekhowski C Tripp W Lorenzon 《Canadian Metallurgical Quarterly》1994,50(2):R546-R549
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Ehsan Mohammadifar Farkhondeh Daneshnia Moosa Kehtari Ali Nemati Kharat Mohsen Adeli 《Polymer International》2016,65(5):559-566
A hyperbranched–linear–hyperbranched (ABA) triblock copolymer containing poly(ethylene glycol) (PEG) as linear block and polyglycerol (hbPG) as hyperbranched blocks has been synthesized through a copper‐catalysed click reaction. In order to synthesize the hyperbranched block, propargyl alcohol‐initiated ring‐opening multibranching polymerization of glycidol was used to prepare hbPG with the propargyl segment in the focal point (CH?C? hbPG). Separately, PEG was functionalized at both ends using cyanuric chloride, and then the chloride groups of cyanuric chloride were substituted by azide groups. Finally, the azide‐functionalized PEG was conjugated to CH?C? hbPG via a click reaction. Substitution of the chlorine atoms of cyanuric chloride under different conditions together with click chemistry allows the synthesis of a variety of polymeric architectures. In the last step, fluorescein was attached to the block copolymer as a fluorescent probe in order to study the cell internalization of this copolymer. This type of triblock copolymer is a promising future nanomaterial for simultaneous drug delivery and cell imaging. © 2016 Society of Chemical Industry 相似文献
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M Gar?on J Arvieux DH Beck EJ Beise A Boudard EB Cairns JM Cameron GW Dodson KA Dow M Farkhondeh HW Fielding JB Flanz R Goloskie S Hoibr?ten J Jourdan S Kowalski C Lapointe WJ McDonald B Nia LD Pham RP Redwine NL Rodning G Roy ME Schulze PA Souder J Soukup I The WE Turchinetz CF Williamson KE Wilson SA Wood W Ziegler 《Canadian Metallurgical Quarterly》1994,49(5):2516-2537
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A. R. Ghahremani M. Jafari M. Ahari A. Hajinezhad A. A. Mozaffari 《Particulate Science and Technology》2018,36(3):270-281
Norouzak oil seeds that are the source of bio-diesel (Norouzak) fuel grow mostly in Gonabad and Kashmar located in Khorasan, north east of Iran. Spray characteristics of Norouzak bio-diesel have been experimentally and theoretically studied in this work. Norouzak fuel is added to the conventional diesel fuel, and mixture formations of several blends have been investigated and compared with each other. Moreover, by varying ambient and injection conditions, behaviors of spray of different blends have been explored. Microscopic and macroscopic properties of spray such as Sauter Mean Diameter (SMD), Ohnesorge number, spray tip penetration, spray cone angle, spray projected area and volume have been examined. To promote mixture formation of the aforementioned sprays, atomization and air entrainment analysis have been performed as well. Furthermore, one can predict experimental results with accuracy of 12% applying suggested theoretical correlations and using error analysis, precision of calculated characteristics has been reported. Results show that increasing injection pressure or adding Norouzak fuel to the blend increases spray tip penetration and reduces spray cone angle. In additions, the results depict that one of the key parameters of improving atomization level of spray is increasing the differences between injection and ambient pressures. 相似文献
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Taheri Motahareh Mozaffari Saeed Keshavarzi Parviz 《Multimedia Tools and Applications》2018,77(13):17043-17067
Multimedia Tools and Applications - Privacy and security are main concerns in face authentication by cloud or semi-honest server. To deal with this problem, a face authentication method based on... 相似文献