We report on a simple, sensitive and selective method for the spectrophotometric determination of Ni 2+ in water samples. The analyte ions were collected on a membrane filter in the form of their red complex with 1-(2-pyridylazo)-2-naphthol (PAN), and the absorption spectra of the colored membrane filters were acquired. Effects of pH value, sample volume, and amount of PAN were examined in order to optimize sensitivity. The interference by common other ions was eliminated using appropriate masking agents. The absorbance is linearly related to the concentration of Ni 2+ in the ranges from 0.3 to 1.5 μg L −1 , and from 2 to 10 μg L −1 , respectively, the correlation coefficients (R 2 ) being 0.9871 and 0.9954. Under the optimal conditions, the detection limit is 0.1 μg L −1 . The recoveries in case of spiked samples are between 95.0% and 101.5%, and the relative standard deviations range from 2.8% to 4.1%.

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In order to effectively assist the researchers conduct quantitative analysis of ceramic microstructures, a segmentation algorithm based on mean shift is used for the ceramic microstructure image. Since the collection and transfer process of microscopic image will inevitably be subject to uneven distribution of light, electronic noise and other interference factors which make the image quality deterioration, it is necessary to reduce noises and enhance edges for ceramic microscopic image processing at first. Therefore, the median filter is used to remove the noises in the ceramic microstructure images. Then the component with similar feature is separated and merged by the mean shift segmentation algorithm. Experiments show the proposed algorithm of using median filter and mean shift clustering gives satisfactory results.

In this paper, AL-Mg-Mn-RE series alloys are becamed object of study.They are prouced with pure alumimum, pure Mg,electrolytic Mn and mix rich Ce rare earth. The effect of rare earth content on the resistance of the Al-Mg-Mn-RE series alloys are investigated by using Anodic polarization curves, electrochemical impendance spectroscopy. The results showed that their corrosivity is influenced by RE content in aluminum alloys.NO.3.3 impedance of Al-Mg-Mn-RE alloys is larger in the Nyquist diagram and its corrosion current of alloy decreases obviously. Then corrosivity of alloy is the best and the RE content is 0.3%,When the RE content is higher or lower than it that corrosivity isn’t improved but descended.

This paper presents a method for inter-class ceramic crack detection threshold than the maximum variance within the class-based segmentation. Ceramics crack detection methods are mainly obtained by ceramic image data, image pre-processing, image segmentation, feature extraction and object recognition constitutes five links. Experimental results show that the method can be detected quickly and accurately detect whether the standard ceramic.