Nowadays, determination of the iron ions with high sensitivity and selectivity with novel methods becomes a matter of urgency for monitoring healthy body and environment. In this paper, for the first time, we present a set of high-performance TiO nanotube arrays which are quite sensitive to iron ions. Firstly, the anodic oxidation method was adopted to prepare ordered TiO nanotube arrays, followed by functionalized Ag nanoparticle deposition with the enhancement ability in iron ion sensing.
View Article and Find Full Text PDFWe present an experimental study of coexisting p(2 × 1) and c(6 × 2) phases on an oxygen-terminated Cu(110) surface by noncontact atomic force microscopy (NC-AFM) at 78 K. Ball models of the growth processes of coexisting p(2 × 1)/c(6 × 2) phases on a terrace and near a step are proposed. We found that the p(2 × 1) and c(6 × 2) phases are grown from the super Cu atoms on both sides of O-Cu-O rows of an atomic spacing.
View Article and Find Full Text PDFZhongguo Zhong Yao Za Zhi
September 2015
This study is to study is to investigate the coumarins from Fruit of Cnidium monnieri and their cytotoxic activities. The constituents were separated by column chromatography, and their structures were elucidated by spectroscopic data analyses. The isolated compounds were evaluated for their cytoxic activities by MTT method.
View Article and Find Full Text PDFZhongguo Zhong Yao Za Zhi
November 2014
This research is to investigate study the flavonoids from stems of Nelumbo nucifera and the cytotoxic activities of iso- lated compounds. The constituents were separated by column chromatography,and their structures were elucidated by spectroscopic data analyses. The isolated compounds were evaluated for cytoxic activities by MTT method.
View Article and Find Full Text PDFIn this paper, the potential sensitivity in Kelvin probe force microscopy (KPFM) was investigated in frequency modulation (FM) and heterodyne amplitude modulation (AM) modes. We showed theoretically that the minimum detectable contact potential difference (CPD) in FM-KPFM is higher than in heterodyne AM-KPFM. We experimentally confirmed that the signal-to-noise ratio in FM-KPFM is lower than that in heterodyne AM-KPFM, which is due to the higher minimum detectable CPD dependence in FM-KPFM.
View Article and Find Full Text PDFThe effect of stray capacitance on potential measurements was investigated using Kelvin probe force microscopy (KPFM) at room temperature under ultra-high vacuum (UHV). The stray capacitance effect was explored in three modes, including frequency modulation (FM), amplitude modulation (AM) and heterodyne amplitude modulation (heterodyne AM). We showed theoretically that the distance-dependence of the modulated electrostatic force in AM-KPFM is significantly weaker than in FM- and heterodyne AM-KPFMs and that the stray capacitance of the cantilever, which seriously influences the potential measurements in AM-KPFM, was almost completely eliminated in FM- and heterodyne AM-KPFMs.
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