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Photo/Electromagnetic Sources
Published in Peter E. J. Flewitt, Robert K. Wild, Physical Methods for Materials Characterisation, 2017
Peter E. J. Flewitt, Robert K. Wild
Generally, X-ray microscopy is used to reveal the microstructure of materials or the flaws contained within them in the form of high-resolution images. The techniques separate into those where a form of X-ray optical element is used as part of the imaging process and those where no such element is used, the latter technique being a derivative of radiography. Radiography remains a widely used non-destructive technique for detecting flaws in materials. However, over the past decade, there have been considerable improvements associated with the non-destructive imaging technique of X-ray computed tomography (CT) (Stock 1999, 2008, 2009, Maire and Withers 2014). The technique is based upon obtaining multiple 2-D digital X-ray intensity image slices of a body and using the image pixels to recreate the 3-D image volume elements. It is noteworthy that the term tomography has roots in the Greek ‘tomos’ to slice or section and ‘graph’ an image or representation. This powerful technique has developed rapidly because of improvements in laboratory-based systems and the availability of synchrotron x-radiation sources (Section 3.3.8.2) with associated potential for improved resolution and image reconstruction (Kak and Slavery 2001).
Ptychographic Imaging of Biological Samples with Soft X-Ray Radiation
Published in Klaus D. Sattler, st Century Nanoscience – A Handbook, 2020
Imaging of unstained cells and biological tissues with X-rays within the water window spectrum offers quantitative analysis routes for biology. X-ray microscopy provides higher spatial resolution than conventional visible light microscopy due to the comparably short wavelength of X-rays. Opposed to high-resolution electron microscopy, the longer absorption length of X-rays allows imaging the interior of comparably thick samples in the micrometer range.
Synthesis, characterization and formation mechanism of Gd2O2S:Pr3+,Ce3+ phosphors by sealed triple-crucible method
Published in Journal of Asian Ceramic Societies, 2020
Xiaotong Sang, Jingbao Lian, Nianchu Wu, Xue Zhang, Jiao He
Lanthanide-doped luminescent materials have received considerable attention for their wide applications in high-resolution displays, integrated optical systems, memory devices, photonics, optoelectronics, afterglow, solid state lasers and especially biological label phosphors [1–3]. Moreover, Gd2O2 S is an excellent luminescent host material, which has been deliberated as a host for optical activation with various numbers of rare-earth ions to reveal different luminescence peaks of the activators [4]. Among them, the Gd2O2 S:Pr3+,Ce3+ phosphors have attracted much attention for their high density (7.34 g.cm−3), high chemical and thermal stability as well as wide band gap energy in the range of 4.6 to 4.8 eV [5,6]. It provides an advantageous high intrinsic X-ray to light conversion efficiency, 1.8 times greater light output than CaWO4 and reasonably long decay time. Then Gd2O2 S phosphors co-doped with Pr3+ and Ce3+ ions are known to be an important imaging system extensively applied in X-ray microscope, soft X-ray phosphor screen for water window, X-ray intensifying screens and so on [7,8].
Development of projection X-ray microscope with 100 nm spot size
Published in Nondestructive Testing and Evaluation, 2022
Norihito Matsunaga, Tomoya Sato, Kota Higuchi, Atsushi Yamada
On the other hand, as one of the microscope technologies using X-rays, a projection type X-ray microscope using an X-ray tube has been developed [10–12]. This microscope enables CT imaging with high spatial resolution by imaging with a high projection magnification while reducing the focal spot size of the X-ray tube. As a result, there is an advantage that imaging optical elements such as Fresnel zone plates and reflection mirrors, which require coherence and high processing accuracy, are no longer required. This can be an advantage in manufacturing a laboratory-sized X-ray microscope that is relatively easy to adjust and low cost.
Study on 3D spatial characterization analysis and water injection seepage numerical simulation of coal micro-pore/fracture
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2020
Wenzheng Zhang, Gang Zhou, Guobao Zhang, Jinjie Duan, Yang Kong, Tao Jiang
In this study, Tianjin Sanying nondestructive high-resolution three-dimensional X-ray microscopy is used to characterize the pore structure of the core in three-dimensional space on the microscale. With Avizo software, the three-dimensional connectivity, porosity, pore throat size and various seepage characteristic parameters of the pore throats of the core are calculated. Figure 1 shows the three-dimensional X-ray microscope used in this study.