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71.
72.
A versatile wet chemistry method is developed for filling of subnanometer sized metal particles in carbon nanotubes with a diameter smaller than 1.5 nm. As an example, we showed that a confined bi-component Pd-V catalyst exhibit a higher benzene hydroxylation activity compared with that within multi-walled carbon nanotubes. 相似文献
73.
Radial flow reactor operated at cross-flow heat transfer is focused for large scale methanol synthesis. The effects of operating conditions including the reactor inlet air temperature, the heating pipe temperature and the air flow rate on the cross-flow heat transfer were investigated and results show that the temperature profile of the area in front of the heating pipe is slightly affected by all the operating conditions. The main area whose temperature profile is influenced is located behind the heating pipe. The heat transfer direction is related to the direction of the flow. In order to obtain the basic parameters for radial flow reactor designing calculation, the dimensionless number group method was used for data fitting of the bed effective thermal conductivity and the wall heat transfer coefficient which were calculated by the mathematical model with the product of Reynolds number and Prandtl number. The comparison of experimental data and calculated values shows that the calculated values fit the experimental data satisfactorily and the formulas can be used for reactor designing calculation. 相似文献
74.
Ying Liang Delong Liu Hou Chen 《Journal of polymer science. Part A, Polymer chemistry》2013,51(9):1963-1968
Well‐defined high oil‐absorption resin was successfully prepared via living radical polymerization on surface of polystyrene resin‐supported N‐chlorosulfonamide group utilizing methyl methacrylate and butyl methacrylate as monomers, ferric trichloride/iminodiacetic acid (FeCl3/IDA) as catalyst system, pentaerythritol tetraacrylate as crosslinker, and L ‐ascorbic acid as reducing agent. The polymerization proceeded in a “living” polymerization manner as indicated by linearity kinetic plot of the polymerization. Effects of crosslinker, catalyst, macroinitiator, reducing agent on polymerization and absorption property were discussed in detail. The chemical structure of sorbent was determined by FTIR spectrometry. The oil‐absorption resin shows a toluene absorption capacity of 21 g g?1. The adsorption of oil behaves as pseudo‐first‐order kinetic model rather than pseudo‐second‐order kinetic model. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
75.
Commercial CaO was modified simply with benzyl bromide. The modified CaO had good water resistance, and characterization by FTIR and TG revealed the modifier was chemically bonded to the CaO surface. Commercial CaO and CaO modified with benzyl bromide were investigated as catalysts for the Henry reaction between benzaldehyde and nitromethane. It was found that the catalytic activity of the modified CaO was greatly improved, with high conversion of benzaldehyde to the (E)-phenyl nitroolefin and 1-phenyl-2-nitroethanol, and with different selectivity from commercial CaO. The effect of modification and reaction conditions on yield, selectivity, and mechanism were studied thoroughly. 相似文献
76.
77.
Shichang Liu Weiqi Chen Kai Fang Xiangning Jiang Ying Gai 《Rapid communications in mass spectrometry : RCM》2012,26(17):2075-2082
78.
Cheng-Ling Pan Chang-Min Hou Lei Zhang Yong Fan Shao-Ding Sheng 《Mendeleev Communications》2012,22(2):109-110
The reaction of potassium pyridyl amido ligand {L = [N(R)(2-C5H3N-6-Me)]–, R = CH2But} with YbI2(thf)2 afforded the linear polymeric complex [K0.5(L)3YbiiK0.5]n, which was characterized by X-ray structure analysis. 相似文献
79.
Xian Tao Ke‐Cheng Shen Qing‐Yun Tang Meng Feng Jiang‐Tao Fang Yu‐Long Wang Ying‐Zhong Shen 《应用有机金属化学》2012,26(7):323-329
New N‐silver(I) acetylbenzamide complexes of type Ln?AgNC9H8O2 (L = PPh3; n = 1, 2a; n = 2, 2b; n = 3, 2c; L = P(OEt)3; n = 1, 2d; n = 2, 2e; n = 3, 2f) were prepared. These complexes were obtained in high yields and characterized by elemental analysis, 1H NMR, 13C{H} NMR, 31P{H} NMR and IR spectroscopy, respectively. The molecular structure of 2b has been determined by X‐ray single‐crystal analysis in which the silver atom is in a distorted tetrahedral geometry and crystallizes as cis–trans. New N‐silver(I) acetylbenzamide complexes have a four‐membered ring, which could influence their chemical and physical properties and modulate volatility. Metal organic chemical vapor deposition experiments were carried out successfully at 400°C and 450°C using 2e as precursor for the deposition of silver films, respectively. The high‐purity silver film obtained at 400°C is dense and homogeneous. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
80.
Shaoyong Ke Zhigang Zhang Ya-Ni Zhang Liqiao Shi Ronghua Zhou Aibing Jiang Ying Liang Ziwen Yang 《Research on Chemical Intermediates》2012,38(8):1827-1837
A novel series of ether functionalization of spiro-tetronic acid derivatives have been designed and conveniently synthesized via three steps, including esterification, one-pot heterocyclization, and etherification reactions. The target molecules have been identified on the basis of analytical spectra data. All newly synthesized compounds have been screened for their potential insecticidal activity against Heliothis armigera and Plutella xylostella compared with spirodiclofen by standard method. 相似文献