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Jinhuan Yao Xuanhai Li Liuping Pan Jiamei Mo 《Metallurgical and Materials Transactions B》2012,43(3):449-459
The synthetic indium-bearing zinc ferrite (IBZF) was activated mechanically using a tumbling mill under different rotation speeds, milling times, media fillings, and ball-to-material ratios. Subsequently, the changes in the physicochemical properties and leaching behavior of IBZF induced by mechanical activation were studied by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectra (FT-IR), M?ssbauer spectrometry, particle size analysis, and leaching tests in sulfuric acid. The results showed that different milling conditions could form different particle size distribution, morphologies, and crystal structures, which influenced indium extraction differently. In addition, the indium extractions from various activated samples were related closely to the changes of physicochemical properties induced by mechanical activation. The strengthening effect of mechanical activation in IBZF decomposition lies mainly in the damage of crystal structure besides the decrease of the particle size because the indium-leaching efficiencies increased significantly with the increase of the damage of the crystal structure when the particle size is kept constant. 相似文献
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Jie TangShenmin Zhu Zhixin ChenChuanliang Feng Yanjun ShenFan Yao Di Zhang Won-Jin MoonDeok-Min Song 《Materials Chemistry and Physics》2012,131(3):706-713
Polypyrrole (PPy) with photonic crystal structures were synthesized from Morpho butterfly wings using a two-step templating process. In the first step photonic crystal SiO2 butterfly wings were synthesized from Morpho butterfly wings and in the second step the SiO2 butterfly wings were used as templates for the replication of PPy butterfly wings using an in situ polymerization method. The SiO2 templates were then removed from the PPy butterfly wings using a HF solution. The hierarchical structures down to the nanometer level, especially the photonic crystal structures, were retained in the final PPy replicas, as evidenced directly by field-emission scanning electron microscope (FE-SEM) and transmission electron microscopy (TEM). The optical properties of the resultant PPy replicas were investigated using reflectance spectroscopy and the PPy replicas exhibit brilliant color due to Bragg diffraction through its ordered periodic structures. The preliminary biosensing application was investigated and it was found that the PPy replicas showed a much higher biological activity compared with PPy powders through their response to dopamine (DA), probably due to the hierarchical structures as well as controlled porosity inherited from Morpho butterfly wings. It is expected that our strategy will open up new avenues for the synthesis of functional polymers with photonic crystal structures, which may form applications as biosensors. 相似文献
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<正>公路中央隔离带的清洗一般是由人工或使用简单清洁设备来完成的,劳动强度大、作业效率低、清洁效果不明显。钢制隔离带通常是由波形板与钢管铆接而成的,截面规则,灰尘附着在隔离带表面,一般的护栏清洗车就可以将其清洗干净。而高侧石隔 相似文献
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在水轮发电机转子现地组装中,大立筋的安装非常重要,直接关系到整个转子圆度和同心度,由于厂家的指导工艺对实际操作描述不够详细,在此对大立筋在安装过程中的难点和易忽略点提出新的见解。 相似文献
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