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Publications (3)1.52 Total impact

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    ABSTRACT: To diminish or eliminate surface damage plays an important role in the production of high precision optical components. Characterisation of the 3D topography of subsurface is a useful method to probe into how subsurface damage forms, the effects it brings and the ways to reduce it. In this paper, we got two kinds of K9 glass samples, one with artificial micro cracks on the ground surface and the other one was ground sample. These two samples were etched in differential models and their 3D topographies during etching were recorded and analysed. For the artificial cracks, each single micro crack was opened gradually till it was fully exposed. The etch rate was almost the same along the horizontal direction, but slower at the vertical direction. For the ground sample, the 3D topography during etching was recorded and it shows that the roughness of ground surface increases at first but starts to decrease after it reaches to a high peak value. The 3D topographies of subsurface damage during etching were evaluated and a numerical model to characterise the initial 3D holographic information of cracks was proposed.
    Int. J. of Nanomanufacturing. 01/2013; 9(5/6):446 - 456.
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    ABSTRACT: Electromotive force (EMF) transient curves presented that the sensor showed good repeatable response in the humidity environments using ambient atmosphere as the carrier gas at different temperatures. The 90% response time and recovery time were within 40 s and 50 s, respectively. The sensor also presented stable response characteristics in 75.1% RH and 83.6% RH humidity environments using N(2), 5% O(2), and 50% O(2) as the carrier gases, respectively. The EMF always increased with the partial pressure of oxygen in certain relative humidity. However, the ΔEMF was decreased with the increase of O(2) content in the carrier gas under the condition of the variation of relative humidity from 75.1% to 83.6%. These phenomena revealed that the sensor was sensitive to water vapor without oxygen in the sample gas and too much water vapor had adverse effect on the response to oxygen. Non-Nernst behavior of the sensor was discussed in detail.
    The Review of scientific instruments 05/2012; 83(5):056103. · 1.52 Impact Factor
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    ABSTRACT: The existence of the subsurface damage of high-precision components is becoming a bottleneck for better performance of high-precision components in the fields of energy, space, national defense equipment, integrated circuit, MEMS and so on. So far there is still no method which is capable of characterizing the 3D topography of subsurface fractures, and this paper presents an idea of investigating the full information of the subsurface damages based on the etching experiments. By micro-indentations some individual subsurface damages with specific geometrical cracks were artificially prepared first, and then dealt with the conventional etching process. The etching process was carried out in the differential mode, namely etching with certain interval time. All 3D topographies of etched cracks during etching were recorded and, dimensions of initial fractures including length, width, depth, etc. were calculated according to the 3D data. Comparison of the calculated results and designed geometrical features indicated that the method used in the paper is a valid method to roughly characterize 3D information of the fractures of the subsurface damage layer and in discussion we proposed a numerical model to accurately characterize the initial 3D holographic information of fractures.
    Manipulation, Manufacturing and Measurement on the Nanoscale (3M-NANO), 2012 International Conference on; 01/2012