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121.
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采用共沉淀法制备不同物质的量比Mn掺杂的铁基载氧体(Mn-Fe2O3),并进行XRD、BET和TEM表征。开展不同温度下Mn-Fe2O3与CO的化学链燃烧实验,研究载氧体的反应特性,确定较优的掺杂量和反应温度。结果表明,适量的Mn掺杂有助于改善铁基载氧体的反应活性,Fe∶Mn物质的量为50∶1时燃烧反应转化率最高。多循环化学链燃烧实验证实了载氧体稳定性较好。不同升温速率(30、40、50℃/min)下反应动力学分析表明,Mn-Fe2O3与CO的化学链燃烧还原反应均属于随机成核和随后生长的Avrami-Erofeev方程模型,并依据模型分别计算出了该模型的活化能和频率因子。 相似文献
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124.
Slow-rise and fast-drop current feature of ultraviolet response spectra for ZnO-nanowire film modulated by water molecules
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This study describes the fabrication of ZnO-nanowire films by electro-chemical anodization of Zn foil.The ZnO films are characterized by field emission scanning electron microscopy,X-ray diffraction patterns,and transmission electron microscopy,respectively.The ultraviolet(UV) photo-response properties of the surface-contacted ZnO film are studied through the current evolution processes under different relative humidities.Unlike the usually observed current spectra of the ZnO films,the drop time is shorter than the rise time.The photo-conductivity gain G and the response time τ are both increased with the increase of the applied bias.The photo-conductivity gain G is lowered with the increase of the environmental humidity,while the response time τ is increased.These results can be explained by considering three different surface processes:1) the electron-hole(e-p) pair generation by the UV light illumination,2) the following surface O2-species desorption,and 3) the photo-catalytic hydrolysis of water molecules adsorbed on the ZnO surface.The slow-rise and fast-drop current feature is suggested to originate from the sponge-like structure of the ZnO nanowires. 相似文献
125.
Back Cover: Improved Electrochromic Performance of Poly(3,4‐ethylenedioxythiophene) by Incorporating a Three‐Dimensionally Ordered Macroporous Structure (Chem. Asian J. 20/2016)
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126.
Direct C—H functionalization of quinoline N-oxides with arylboronic acids is achieved using KMnO_4 as the sole and efficient oxidative system.This method provides an efficient protocol to construct regioselectively 2-arylquinoline N-oxides via radical cross-coupling reaction in moderated to good yields under mild conditions. 相似文献
127.
A Cu(OAc)2-catalyzed synthesis of 2-arylquinoline N-oxides with easily available arylamines is described. The main features of this reaction are mild reaction conditions, high functional-group tolerance, excellent regioselectivity, and good to excellent yields. This procedure is mild, operationally simple, and constitutes a greener approach to the arylation of quinoline N-oxides. 相似文献
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129.
Zhifu Jiang Jian Zhao Beibei Gao Shuo Chen Wenyan Qu Xiangdong Mei 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1026-1037
Abstract A series of novel (4′-tosyl) piperidin-4-yl containing α-aminophosphonates were synthesized by a one-pot reaction, efficiently catalyzed by magnesium perchlorate, under solvent-free conditions from 1-tosylpiperidin-4-one, substituted aromatic amines, and diethyl phosphite (DEP). The synthesized compounds were characterized by IR, 1H NMR, 13C NMR, 31P NMR, and HRMS spectroscopy. A single-crystal X-ray structure of diethyl 4-(2-chlorophenyl) amino-1-(4’-methylbezenesulfonyl) piperidin-4-yl-phosphonate (2a) was obtained, and some of the title compounds displayed insecticidal activities against Plutella xylostella. Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfer, and Silicon and the Related Elements for the following free supplemental files: Additional figures and tables. 相似文献
130.
Guang-Feng Hong Zhen-Hua Dong Yong-Mei Xiao Pu Mao Ling-Bo Qu 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):771-779
AbstractA practical metal-free procedure for the synthesis of (E)-vinyl sulfones has been developed through the coupling of β-nitrostyrenes with sodium sulfinates under microwave irradiation. This methodology provides a convenient and efficient approach to various (E)-vinyl sulfones from readily available starting materials with excellent regioselectivity. The present oxidative reaction involves an efficient denitrative radical cross-coupling of β-nitrostyrenes with sodium sulfinates via using AcOH as an additive. 相似文献