摘要：The design,fabrication and characterization of the x-ray supermirrors are discussed in this *** the local optimization method of simplex algorithm and the global one of simulated annealing algorithm with different initial multilayer structures,we designed the broad angular band supermirrors with different grazing incidence angle intervals at the energy of 8.0 keV(the Kαline of Cu)and the broad energetic band supermirrors with different energy intervals at fixed grazing incidence *** fabricating techniques for depositing non-periodic multilayers are also *** W/C and W/Si supermirrors are deposited on silicon substrates and characterized by a high resolution x-ray D1 diffractometer from Bede Company,*** the interface roughness and the densities of the materials as independent variables,some measured reflectivity curves are fitted using the Debye-Waller factor with interface *** experimental results show that the optical performances of the fabricated supermirrors are in agreement with the designed ones.

摘要：Synchrotron radiation x-ray micro-computed tomography(SR-μCT)is a 3D imaging technique that is widely employed for the characterization of defects in advanced materials and *** this study,we characterize several typical defects in octettruss and re-entrant 3D lattice structures by using SR-μ*** 3D micro-lattice structures are manufactured using projection micro litho stereo exposure(PμLSE)additive manufacturing *** as-fabricated 3D lattice samples are characterized using optical microscopy,and subsequently,by SR-μ*** more,a statistical analysis is performed to characterize the surface roughness and internal defects qualitatively,whereby the statistical geometrical parameters of struts along different directions and strut joints are analyzed and ***,several typical defects are identified:(1)holes at the joints of the strut and irregular diameter deviations of the strut in the octet-truss lattice structure;(2)irregular diameter variations,bulges,dislocations,grooves,accumulations,and torsion in the re-entrant lattice *** of these defects are related to the building direction,the weight of the structure,bubbles,dust,and impurities during the PμLSE additive manufacturing process.

摘要：A readout system for x-ray CCDs based on an improved architecture is presented; by optimizing several critical circuit blocks along the analog signal chain, the conflict between the readout speed and readout noise is greatly alleviated. Using CCD47-10 as its target CCD, the readout system has achieved 8.6e^- readout noise and 142 eV FWHM at 5.9 keV Mn Kα under a pixel rate of 80 kHz. Also its performance of imaging has been investigated.

摘要：A random method used for improving light throughput of a soft x-ray multilayer has been developed in the 18-20 nm spectral region, based on the traditional theory of periodic multilayer, and an 8% gain in integrated reflectance is obtained. The ensemble calculation is presented at the same time, and the multilayer is fabricated by magnetron sputtering.

摘要：Beijing Synchrotron Radiation Facility is a partly dedicated synchrotron radiation source operated in either parasitic or dedicated mode. The 3B1A beamline, extracted from a bending magnet, was originally designed as a soft x-ray beamline for submicro x-ray lithography with critical lateral size just below 1μm in 1988 and no change has been made since it was built. But later the required resolution of x-ray lithography has changed from sub-micrometre to the nanometre in the critical lateral size. This beamline can longer more meet the requirement for x-ray nano lithography and has to be modified to fit the *** upgrade the design of the 3B1A beamline for x-ray nano lithography, a mirror is used to reflect and scan the x-ray beam for the nano lithography station, but the mirror's grazing angle is changed to 27.9mrad in the vertical direction and the convex curve needs to be modified to fit the change; the tiny change of mirror scanning angle is firstly considered to improve the uniformity of the x-ray spot on the wafer by controlling the convex curve.

摘要：针对肺部x-ray图像在超分辨率重建过程中出现的肺部边缘不清晰以及器官纹理模糊等问题,提出一种基于多级残差注意力的x-ray图像超分辨率重建方法。将注意力机制嵌入残差块中构建网络基本块,在加速网络收敛的同时,使网络更加关注图像的边缘纹理特征;设计多尺度特征融合模块进行特征提取,保证结构信息的完整性;通过多级残差学习加速网络训练,并允许构建更深层次的网络;融合上采样图像与Bicubic图像完成最终重建,弥补特征提取过程中的特征损失。实验结果表明,所提出模型的PSNR、SSIM均高于现有算法,且重建出的图像具备更加丰富的细节和清晰的边缘。

摘要：研究了在Λ型三能级类氦碳离子C^(4+)体系中波长为4.03nm的x-ray超辐射的产生,探讨了紫外波段的相干光场的耦合作用对x-ray超辐射产生的量子相干调控.通过数值模拟离子间和离子内部的干涉效应,发现控制离子密度和耦合相干光场强度可以实现对超辐射的脉冲强度和脉冲分裂特征的调控.当驱动光场的Rabi频率由4.3"10^(13)Hz增加到1.7"10^(14)Hz时,出射脉冲的最大输出强度增加约150倍.随着驱动光场Rabi频率的增加,最大脉冲输出强度呈现收窄震荡趋势.其结果对设计x-ray源具有潜在的应用价值.

摘要：The article is to study the development of computer-aided design of x-ray microtomography—the device for investigating the structure and construction of three-dimensional images of organic and inorganic objects on the basis of shadow projections. This article provides basic information regarding CAD of x-ray microtomography and a scheme consisting of three levels. The article also shows basic relations of x-ray computed tomography, the generalized scheme of an x-ray microtomographic scanner. The methods of x-ray imaging of the spatial microstructure and morphometry of materials are described. The main characteristics of an x-ray microtomographic scanner, the x-ray source, x-ray optical elements and mechanical components of the positioning system are shown. The block scheme and software functional scheme for intelligent neural network system of analysis of the internal microstructure of objects are presented. The method of choice of design parameters of CAD of x-ray microtomography aims at improving the quality of design and reducing costs of it. It is supposed to reduce the design time and eliminate the growing number of engineers involved in development and construction of x-ray microtomographic scanners.

摘要：为分析定向钢纤维混凝土中钢纤维的分布,通过x-CT扫描原位测试确定了混凝土中所有钢纤维的空间位置坐标,根据钢纤维空间坐标,分析计算钢纤维的角度分布及纤维方向效应系数。结果表明,定向钢纤维混凝土中,与设计的目标方向夹角<30°的钢纤维根数占总数量的比例达85%,定向钢纤维的定向效果较好;定向钢纤维混凝土中纤维方向效应系数增加25%,增强效率显著提高。

摘要：利用x-ray CT技术,获取沥青混合料内部结构组成,分析体积参数,进而完成沥青混合料的计算机辅助设计的研究已成为沥青路面技术领域的关注热点.重点介绍了在利用x-ray CT进行沥青混合料体积组成分析与差异性物质辨识、混合料内部结构组成的三维图像重构、沥青混合料性能的虚拟试验等方面研究时存在的问题和可能的解决方法.同时,提出了进一步研究所需要解决的一些关键技术,给出了一个技术路线图以供日后的研究参考.