Search

Identification and characterization of CTCs can be used as a tool for the study of cancer metastases. A novel design of microfluidic chip used for enrichment of circulating tumor cells is presented in this paper. An integration of DLD method and negative enrichment method were designed to improve the throughput and recovery rate while getting intact CTCs. The DLD stage is used to separate CTCs from blood cells preliminarily, and the negative enrichment stage is used to acquire purified CTCs. Both of them were simulated with COMSOL Multiphysics. Simulation results showed that triangular micro-posts have better performance in DLD stage, and wave structures could generate better disturbance effect than herringbone structures. This chip provides a potential approach with high throughput and purity for the enrichment of CTCs.

In this work, sodium tantalate (NaTaO3) microrods were successfully prepared by anodic oxidation of tantalum in 30% NaOH electrolyte. The morphology and structure of microrods were characterized by scanning electronic microscope (SEM), energy dispersive spectrometer (EDS) and X-ray diffraction (XRD), respectively. SEM analysis shows the formation of microrods with an average length of 12.8 μm and a diameter of 2.3 μm. XRD analysis reveals that the as-prepared microrods are amorphous. After annealing in nitrogen at 800 °C, the amorphous NaTaO3 microrods transform into orthorhombic structure. Experimental results indicate that the microrods have a high photoelectrochemical property. The possible formation mechanism of NaTaO3 microrods has also been discussed.

Iron titanium oxides with different Ti:Fe ratios (molar ratio: 3:1, 2:1, 1:1, 1:2, 1:3) have been prepared by chemical coprecipitation process. The structures and properties of the samples have been characterized by X-ray diffraction, vibrating sample magnetometer and UV-vis spectrophotometer. Results show that the samples annealed at 460 °C have poor crystallinity. At 550 °C, the crystallinity of all the samples increased strikingly. The iron titanium oxides contained anatase TiO2, rutile TiO2, α-Fe2O3and/or Fe2TiO5. Ti:Fe ratios have a great influence on the detailed phase compositions of each sample. The iron titanium oxides exhibited paramagnetism and the intensity of magnetization increased with the increasing content of Fe. Band gap energies of the oxides changed slightly with increasing content of Fe with an average value of 2.0 eV, obviously lower than that of TiO2.

This work presents a novel approach for preparing Cu-loaded TiO2 nanotube arrays through alternating current electrodeposition. The Cu content loaded on the arrays was controlled by changing the concentration of Cu (NO3)2 solution, deposition voltage and time. The surface morphology and crystal structure of Cu-loaded TiO2 nanotube arrays were characterized by scanning electron microscopy (SEM) and the X-ray diffraction (XRD). The effects of Cu content on the photoelectrochemical property were studied in detail. Results show that Cu-loaded TiO2 nanotube arrays have evidently enhanced photoelectrochemical activity. The photocurrent of Cu-loaded TiO2 nanotube arrays prepared in 0.00625 mol/L Cu (NO3)2 solution at 12 V for 20 seconds was 5.7 and 2.3 times as that of unloaded TiO2 nanotube arrays under visible and UV radiation, respectively.

In this work, highly-ordered TiO2 nanotube arrays were prepared by constant-voltage anodization, followed by electrodeposition of Ag to obtain Ag-loaded TiO2 (Ag-TiO2) nanotube arrays via alternating current (AC) process. The results of SEM and XRD show that the morphology and crystal structure of Ag-TiO2 layer depend greatly on the electrodeposition parameters. Ag-TiO2 nanotube arrays prepared in 2.5 mmol/L AgNO3 solution by electrodeposition with applied voltage of 12 V for 1 minute performed the best photoelectrochemical current response and photocatalystic activity. The photocurrent density of Ag-TiO2 is 43.32 μA/cm2 under sunlight irradiation (70 mW/cm2), which is 4.2 times as that of unloaded TiO2 nanotube arrays. Methyl orange (MO) degradation rate with the Ag-TiO2 nanotube arrays achieves 52.13% after 90 min sunlight irradiation which is obvious higher than that of TiO2 nanotube arrays. The mechanism of enhancing photoelectrochemical activity of decorating titania with Ag has also been discussed in the view of energy band theory.

Dispersing barium titanate (BT) in aqueous media has received special attention due to economic and environmental considerations. A new kind of dispersant named poly (acrylic acid-co-itaconic acid) has been synthesized in our study. By adjusting reactant ratio and reactant condition poly (acrylic acid-co-itaconic acid) with different average molecular (2000~10000) and different content of itaconic acid (10% ~ 30%) have been obtained. Dispersing effects of poly (acrylic acid-co-itaconic acid) have been studied through zeta potential, sediment experiments, rheological behavior. It can be concluded from our study poly (acrylic acid-co-itaconic acid) containing 20% itaconic acid with Mw between 3000 and 5000 show the best dispersing effect.

BaTiO3 films with a thickness up to 3 μm were fabricated under the hydrothermal conditions. It was found that the crystallinity of BaTiO3 increases with the concentration of Ba(OH)2 solutions. Along with the increasing of time, the crystallinity of BaTiO3 increases, reaches the maximum value and then decreases. The measured values of remanent polarization (Pr) and coercive field (Ec) are 1.74μC/cm2 and 24KV/cm. The leakage of the films at 1V is 10-7A/cm2. The dielectric constant and loss tangent of hydrothermal derived BaTiO3 film at a frequency of 1 KHz were 600 and 0.2, respectively.