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101.
Jibin Pu Xiufang Liu Liping Wang Qunji Xue 《Surface and interface analysis : SIA》2011,43(10):1332-1340
Several single‐component and two‐component imidazolium ionic liquids (ILs) ultrathin films were formed on Si substrates by a dip‐coating and heat treatment process. The formation and surface properties of the films were analyzed by means of ellipsometric thickness measurement, X‐ray photoelectron spectra and atomic force microscope. The adhesive and nanotribological behaviors of the films were evaluated by a homemade colloidal probe. A ball‐on‐plate tribometer was used to test the microtribological performances of these films. As a result, the two‐component ILs ultrathin film containing 80% solid‐like ILs phase shows more homogenous surface morphologies and optimal micro/nano‐tribological properties as compared to single‐component ILs films, which is ascribed to a synergic effect between the steady solid‐like ILs phase as the backbone and the proper amount of flowable liquid‐like ILs phase. By studying the influence of various solid/liquid ILs ratios on tribological properties of the two‐component ILs films, we might find the way to design ILs films with excellent comprehensive tribological properties. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
102.
103.
Liangru Yang Yunfei Li Pu Mao Jinwei Yuan Yongmei Xiao 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):780-788
AbstractThe catalytic activity of a series of chiral heteroaryl coordinated chelating N-heterocyclic carbene (NHC) palladium complexes towards asymmetric allylic alkylation (AAA) were presented here. The effects of different N-substituents, NHC backbones and chelate rings on the catalytic activity and the enantioselectivity of the alkylation of (E)-1,3-diarylallyl acetates with dialkyl malonate were investigated. The results showed that, under the optimized conditions, complexes 3a, 3b, and 3i carrying the pyridinyl-coordinated five-membered chelate ring showed high catalytic activity and chiral induction efficiency. The corresponding alkylated products were obtained in high yields with moderate ee. Furthermore, it was found that the substituents of (E)-1,3-diarylallyl acetates and the type of the nucleophile affect the results as well. 相似文献
104.
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
105.
Yi-Bo Li Jin-Zhou Zhao Wan-Fen Pu Hu Jia Huan Peng Dong Zhong Sheng-Kui Wang 《Journal of Thermal Analysis and Calorimetry》2013,113(2):579-587
This research aimed at the investigation of the effect of different metallic additive on the combustion and kinetic behavior of crude oil. For this purpose, the thermal behavior of the oil-only and oil–metallic salts mixtures were studies by the thermogravimetry (TG)/derivative thermogravimetry and differential scanning calorimetry (DSC) on heating rate at 10 °C min?1. The result shows that Dagang crude oil exhibited apparent low temperature oxidation (LTO), fuel deposition, and high temperature oxidation processes. With the addition of metallic salts, the LTO process has been shortened and samples added CuSO4, CrCl3·6H2O, and AlCl3·6H2O achieved a much lower peak temperature than that of oil. Based on the Arrhenius model, metallic additives were proven to have obvious influence on the combustion activation energy. And, by comprehensive analysis of TG/DSC profile and activation energy, ZnSO4 exhibited a positive influence on light crude oil combustion during the high pressure air injection process. 相似文献
106.
Yuqiao Wang Huijun Zhang Dan Yao Junjie Pu Yuan Zhang Xiaorui Gao Yueming Sun 《Journal of Solid State Electrochemistry》2013,17(3):881-887
Graphene/Fe3O4 nanocomposite was prepared for the immobilization of hemoglobin (Hb) to improve the electron transfer between Hb and glass carbon electrode (GCE). The characterization of nanocomposites was described by transmission electron microscopy, Fourier transform infrared, Raman spectroscopy, and X-ray photoelectron spectroscopy, respectively. The electrochemistry of Hb on the graphene/Fe3O4-based GCE was investigated by cyclic voltammetry and amperometric measurement. The modified electrode showed a wide linear range from 0.25 μmol/L to 1.7 mmol/L with a correlation coefficient of 0.9967. The detection limit of the H2O2 biosensor was estimated at 6.0?×?10?6?mol/L at a signal-to-noise ratio of 3. 相似文献
107.
P. Pu H. Cachet E. Ngaboyamahina E. M. M. Sutter 《Journal of Solid State Electrochemistry》2013,17(3):817-828
Two types of TiO2 nanotubular arrays were obtained by anodisation of a titanium foil, in two different solutions containing fluoride ions. For the first type which has rough tube walls, impedance measurements in the dark showed the presence of a localised surface state which was related to adsorbed molecular water. Under UV illumination, this adsorbed molecular water was photo-dissociated. Moreover, an increase of 2 orders of magnitude for the limiting capacitance of the space charge layer was observed, simultaneously with the disappearance of the localised state and with a 100-time increase of the carrier density associated with hydrogen insertion. The second type of layer was characterised by smoother tube walls, a high doping level (1020?cm?3) in the dark, a lack of localised states and no long-lasting photo-induced effect. In this case, the width of the space charge layer became rapidly higher than the half-thickness of the tube walls, when the applied potential increased. Therefore, the walls were progressively depleted under anodic polarisation, passing from a situation where the tubes were totally active in the cathodic range towards a situation where the contribution of the tube walls could be neglected. 相似文献
108.
A novel and efficient route to H-pyrazolo[5,1-a]isoquinoline-1-carbaldehydes via a tandem reaction of N′-(2-alkynylbenzylidene)hydrazide with 2-vinyloxirane is described. The reaction proceeds through a silver(I)–rhodium(I) cooperative catalysis. 相似文献
109.
Xiyan Li Wei Gao Prof. Hongjie Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(8):2889-2894
Self‐assembled Bi2Te3 one‐dimensional nanorod bundles have been fabricated by a low‐cost and facile solvothermal method with ethylene diamine tetraacetic acid as an additive. The phase structures and morphologies of the samples were characterized by X‐ray diffraction, scanning electron microscopy, Fourier‐transform infrared spectrometry, and transmission electron microscope measurements. The growth mechanisms have been proposed based on the experimental results. The full thermoelectric properties of the nanorod bundles have been characterized and show a large improvement in the thermal conductivity attributed to phonon scattering of the nanostructures and then enhance the thermoelectric figure of merit. This work is promising for the realization of new types of highly efficient thermoelectric semiconductors by this method. 相似文献
110.
Xinjian Yang Zhen Liu Zhenhua Li Fang Pu Prof. Dr. Jinsong Ren Prof. Dr. Xiaogang Qu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(31):10388-10394
Hydrophobicity has been an obstacle that hinders the use of many anticancer drugs. A critical challenge for cancer therapy concerns the limited availability of effective biocompatible delivery systems for most hydrophobic therapeutic anticancer drugs. In this study, we have developed a targeted near‐infrared (NIR)‐regulated hydrophobic drug‐delivery platform based on gold nanorods incorporated within a mesoporous silica framework (AuMPs). Upon application of NIR light, the photothermal effect of the gold nanorods leads to a rapid rise in the local temperature, thus resulting in the release of the entrapped drug molecules. By integrating chemotherapy and photothermotherapy into one system, we have studied the therapeutic effects of camptothecin‐loaded AuMP‐polyethylene glycol‐folic acid nanocarrier. Results revealed a synergistic effect in vitro and in vivo, which would make it possible to enhance the therapeutic effect of hydrophobic drugs and decrease drug side effects. Studies have shown the feasibility of using this nanocarrier as a targeted and noninvasive remote‐controlled hydrophobic drug‐delivery system with high spatial/temperal resolution. Owing to these advantages, we envision that this NIR‐controlled, targeted drug‐delivery method would promote the development of high‐performance hydrophobic anticancer drug‐delivery system in future clinical applications. 相似文献