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关键词： Synchrotron radiation  

摘要： Objective Compound refractive lens (CRL) is an indispensable component for focusing high-energy X-rays in the new generation of light source scientific apparatus. CRL achieves focusing by stacking multiple unit lenses, which can easily lead to the accumulation of error defects. Various problems often arise during their fabrication, such as surface deviations, relative transverse offsets, and mutual tilt angles of the front and back surfaces, which can affect the intensity and focal position of the focused beam. It is very important to measure these parameters without damaging the sample to adjust process parameters and optimize lens application. For two-dimensional focusing lenses, microscopy can only detect the single-sided surface profile, and wavefront metrology methods such as X-ray speckle can only qualitatively judge the alignment by restoring figure errors. X-ray computed tomography (CT) can meet the need for overall characterization of the three-dimensional structure of the lens, but there is a problem of missing subsequent data processing. To solve the issue of three-dimensional profile characterization of hyperbolic refractive lenses, we propose a measurement method based on point cloud processing. By fitting and calculating the surface point cloud model obtained from X-ray CT, typical doublesided processing quality parameters, including relative transverse offset, mutual tilt angle, and single-sided curvature radius, can be accurately measured, which provide accurate and detailed data support for fabrication optimization. Methods This method is mainly divided into three steps: first, X-ray CT scanning is used for three-dimensional reconstruction;then, the surface boundary point cloud data is extracted through threshold segmentation;finally, the point cloud model is segmented, fitted, and calculated. In the first step, the sample is scanned using synchrotron radiation X-ray CT to obtain several projection images, which are reconstructed into a three-dimens

关键词： X ray films  

摘要： Aiming at the problem that high-gray-scale X-ray negative images cannot be displayed directly on low-level monitors. an adaptive enhancement algorithm for high-grayscale X-ray negative images based on statistical decision-making was pro-posed. In view of the problem that 12bit high grayscale images could not be displayed, a RAW-Optical mapping algorithm was designed to quantize 12bit images to 16bit lossless display, For the problem that the gray value after mapping was too concen trated, the image was whitened and the contrast was too low, the upper and lower limits of the cropping variable were deter-mined according to the image quantization characteristics and the ARAW-Optical algorithm was designed to dynamically stretch the gray scale of the image to improve the image contrast. Taking advantage of the prominent feature of weld seam structure information of industrial X-ray films an automatic exposure discrimination model based on statistical decision-making was designed by introducing the average grayscale difference and average deviation, and an adaptive grayscale correction algo-rithm AGRAW-Optical was designed according to the exposure degree to achieve image brightness correction and enhance im age detail information. The experimental results showed that the proposed method could effectively realize the clear display of high gray-scale images, improve the visual perception of weld information, and enhance the interpretation and identification of industrial X-ray film welding slogans, welding dates and defect information. Especially in the low-illumination X-ray negative image processing, compared with the existing advanced algorithms, various indicators had been greatly improved. the informa tion entropy was increased by 0.58%, the effective efficiency of edge information was increased by 12. 75 times, the contrast was increased by 0,24%, and the image clarity index was improved nearly 10 times. © 2025 CIMS. All rights reserved.

摘要： 《核聚变与等离子体物理》(季刊)是中国核学会核聚变与等离子体物理学会会刊,是中文物理学类、原子能技术类核心期刊,由核工业西南物理研究院主办,1980年创刊,国内外公开发行.

关键词： I型胶原酶   EGCG   分子对接   荧光光谱   酶活力调控  

摘要： 制革生产过程中酶脱毛方法容易造成胶原蛋白过度水解，粒面损伤，为保证最终成革质量，对脱毛过程中胶原酶活性的调控至关重要。对混合孵育的表没食子儿茶素没食子酸酯(EGCG)与I型胶原酶进行了胶原蛋白水解活力的测定，同时通过紫外光谱、荧光光谱和分子对接技术探究EGCG对I型胶原酶的结构影响。实验结果表明，EGCG的添加可以有效抑制I型胶原酶的活性，当浓度为100 μmol/L时，对I型胶原酶的胶原水解活性的抑制率达到86.06%。EGCG与I型胶原酶活性中心的催化Zn(II)离子配位，并与蛋白酶分子中的氨基酸残基存在氢键和疏水相互作用，导致蛋白酶的荧光发生猝灭，胶原酶活力降低。研究结果为胶原酶活性调控剂的筛选和设计提供了思路。