In this work,an old scanning electron microscope(SEM)is refurbished to enhance its image processing capability.How to digitally sample and process an analog image is also presented.An NI PCI-6259 multiple input/output...In this work,an old scanning electron microscope(SEM)is refurbished to enhance its image processing capability.How to digitally sample and process an analog image is also presented.An NI PCI-6259 multiple input/output data acquisition(DAQ)board is used to acquire signals originally being sent to an analog display,and then convert the signals into a digital image.Two output channels are used for raster scan of the horizontal and verticle axes of the image buffer,while one input channel is used to read the brightness signals at various coordinate points.Synchronous method is used to maximize the DAQ speed.Finally,the digitally buffered images are read out to display and saved in a hard drive.The hardware and software designs of this work are explained in great detail,which can serve as a very good example for fast synchronous DAQ,advanced virtual instrument design and structural driver programming with LabVIEW.展开更多
The coarse pore system, interfacial transition zone （ITZ） between aggregate and paste matrix and volume fraction of unhydrated cement in concrete （w/c=0.3） containing mineral admixtures were quantitatively charact...The coarse pore system, interfacial transition zone （ITZ） between aggregate and paste matrix and volume fraction of unhydrated cement in concrete （w/c=0.3） containing mineral admixtures were quantitatively characterized by the scanning electron microscope-backscattered electron （SEM-BSE） image analysis technique. The experimental results show that compound addition of slag and fly ash decreases the coarse porosity from 10.17% to 3.74% and the threshold diameter of coarse pore size from 345 μm to 105 μm compared with concrete （w/c=0.30） without mineral admixtures; Moreover with compound addition of fly ash and slag, the volume proportion of unhydrated cement in paste matrix is reduced by 30%, the maximum amount of coarse pores in the ITZ between aggregate and paste decreases from 13.11% to 5.57% and the thickness of ITZ is reduced by 37% , compared with concrete without mineral admixtures.展开更多
Recent advances in the ultrafast transmission electron microscope （UTEM）, with combined spatial and temporal resolutions, have made it possible to directly visualize the atomic, electronic, and magnetic structural d...Recent advances in the ultrafast transmission electron microscope （UTEM）, with combined spatial and temporal resolutions, have made it possible to directly visualize the atomic, electronic, and magnetic structural dynamics of materials. In this review, we highlight the recent progress of UTEM techniques and their applications to a variety of material systems. It is emphasized that numerous significant ultrafast dynamic issues in material science can be solved by the integration of the pump-probe approach with the well-developed conventional transmission electron microscopy （TEM） techniques. For instance, UTEM diffraction experiments can be performed to investigate photoinduced atomic-scale dynamics, including the chemical reactions, non-equilibrium phase transition/melting, and lattice phonon coupling. UTEM imaging methods are invaluable for studying, in real space, the elementary processes of structural and morphological changes, as well as magnetic-domain evolution in the Lorentz TEM mode, at a high magnification. UTEM electron energy-loss spectroscopic techniques allow the examination of the ultrafast valence states and electronic structure dynamics, while photoinduced near-field electron microscopy extends the capability of the UTEM to the regime of electromagnetic-field imaging with a high real space resolution.展开更多
页岩扫描电镜(scanning electron microscope,SEM)图像智能识别能够快速分析页岩储层矿物,是页岩油储层“甜点”预测的重要手段之一,也是未来的技术发展趋势。传统方法在鉴定矿物成分时存在自动化程度低、样本适配度低和特征提取受限等...页岩扫描电镜(scanning electron microscope,SEM)图像智能识别能够快速分析页岩储层矿物,是页岩油储层“甜点”预测的重要手段之一,也是未来的技术发展趋势。传统方法在鉴定矿物成分时存在自动化程度低、样本适配度低和特征提取受限等问题。为此,本文提出基于BlendMask的页岩SEM图像鉴定方法。首先,采用双边滤波、拉普拉斯和图像归一化等图像预处理技术对原始图像进行去噪、锐化和像素统一处理,提高训练样本的质量;然后,采用旋转、缩放、光度变化等图像增广方法构建增广策略,扩大数据集数量;最后,利用注意力机制和深度可分离卷积改进BlendMask网络,实现图像的成分分割与识别。应用于海塔盆地的页岩SEM图像实验结果表明,相比BlendMask模型,改进后方法的分割准确率和召回率分别提升了0.02~0.20和0~0.59,分割用时减少了1.29~2.70 s。展开更多
扫描电子显微镜(scanning electron microscope,SEM)在材料表征领域具有广泛的应用前景,然而所获得的图像通常难以直接提取定量信息。针对一种共晶高熵合金的扫描电镜图像,提出了一种基于机器学习和图像分割技术的自动化、定量化分析方...扫描电子显微镜(scanning electron microscope,SEM)在材料表征领域具有广泛的应用前景,然而所获得的图像通常难以直接提取定量信息。针对一种共晶高熵合金的扫描电镜图像,提出了一种基于机器学习和图像分割技术的自动化、定量化分析方法,该方法能够有效测量共晶高熵合金板条状区域的面积、长度、宽度、周长以及不同组分的占比。实验结果表明,本研究所提出的方法在高熵合金图像上具有良好的鲁棒性和准确性,为研究高熵合金材料的表面结构提供了重要的技术支持。展开更多
文摘In this work,an old scanning electron microscope(SEM)is refurbished to enhance its image processing capability.How to digitally sample and process an analog image is also presented.An NI PCI-6259 multiple input/output data acquisition(DAQ)board is used to acquire signals originally being sent to an analog display,and then convert the signals into a digital image.Two output channels are used for raster scan of the horizontal and verticle axes of the image buffer,while one input channel is used to read the brightness signals at various coordinate points.Synchronous method is used to maximize the DAQ speed.Finally,the digitally buffered images are read out to display and saved in a hard drive.The hardware and software designs of this work are explained in great detail,which can serve as a very good example for fast synchronous DAQ,advanced virtual instrument design and structural driver programming with LabVIEW.
文摘The coarse pore system, interfacial transition zone （ITZ） between aggregate and paste matrix and volume fraction of unhydrated cement in concrete （w/c=0.3） containing mineral admixtures were quantitatively characterized by the scanning electron microscope-backscattered electron （SEM-BSE） image analysis technique. The experimental results show that compound addition of slag and fly ash decreases the coarse porosity from 10.17% to 3.74% and the threshold diameter of coarse pore size from 345 μm to 105 μm compared with concrete （w/c=0.30） without mineral admixtures; Moreover with compound addition of fly ash and slag, the volume proportion of unhydrated cement in paste matrix is reduced by 30%, the maximum amount of coarse pores in the ITZ between aggregate and paste decreases from 13.11% to 5.57% and the thickness of ITZ is reduced by 37% , compared with concrete without mineral admixtures.
基金Project supported by the National Basic Research Program of China(Grant No.2015CB921300)the National Key Research and Development Program of China(Grant Nos.2016YFA0300300,2017YFA0504703,and 2017YFA0302900)+3 种基金the National Natural Science Foundation of China(Grant Nos.11604372,11474323,and 11774391)the”Strategic Priority Research Program(B)”of the Chinese Academy of Sciences(Grant No.XDB07020000)the Scientific Instrument Developing Project of the Chinese Academy of Sciences(Grant No.ZDKYYQ20170002)the financial support of the Hundred Talent Program B from CAS
文摘Recent advances in the ultrafast transmission electron microscope （UTEM）, with combined spatial and temporal resolutions, have made it possible to directly visualize the atomic, electronic, and magnetic structural dynamics of materials. In this review, we highlight the recent progress of UTEM techniques and their applications to a variety of material systems. It is emphasized that numerous significant ultrafast dynamic issues in material science can be solved by the integration of the pump-probe approach with the well-developed conventional transmission electron microscopy （TEM） techniques. For instance, UTEM diffraction experiments can be performed to investigate photoinduced atomic-scale dynamics, including the chemical reactions, non-equilibrium phase transition/melting, and lattice phonon coupling. UTEM imaging methods are invaluable for studying, in real space, the elementary processes of structural and morphological changes, as well as magnetic-domain evolution in the Lorentz TEM mode, at a high magnification. UTEM electron energy-loss spectroscopic techniques allow the examination of the ultrafast valence states and electronic structure dynamics, while photoinduced near-field electron microscopy extends the capability of the UTEM to the regime of electromagnetic-field imaging with a high real space resolution.
文摘页岩扫描电镜(scanning electron microscope,SEM)图像智能识别能够快速分析页岩储层矿物,是页岩油储层“甜点”预测的重要手段之一,也是未来的技术发展趋势。传统方法在鉴定矿物成分时存在自动化程度低、样本适配度低和特征提取受限等问题。为此,本文提出基于BlendMask的页岩SEM图像鉴定方法。首先,采用双边滤波、拉普拉斯和图像归一化等图像预处理技术对原始图像进行去噪、锐化和像素统一处理,提高训练样本的质量;然后,采用旋转、缩放、光度变化等图像增广方法构建增广策略,扩大数据集数量;最后,利用注意力机制和深度可分离卷积改进BlendMask网络,实现图像的成分分割与识别。应用于海塔盆地的页岩SEM图像实验结果表明,相比BlendMask模型,改进后方法的分割准确率和召回率分别提升了0.02~0.20和0~0.59,分割用时减少了1.29~2.70 s。
文摘扫描电子显微镜(scanning electron microscope,SEM)在材料表征领域具有广泛的应用前景,然而所获得的图像通常难以直接提取定量信息。针对一种共晶高熵合金的扫描电镜图像,提出了一种基于机器学习和图像分割技术的自动化、定量化分析方法,该方法能够有效测量共晶高熵合金板条状区域的面积、长度、宽度、周长以及不同组分的占比。实验结果表明,本研究所提出的方法在高熵合金图像上具有良好的鲁棒性和准确性,为研究高熵合金材料的表面结构提供了重要的技术支持。
