Computer reconstructed X-ray imaging

Computed tomography is a method for obtaining a series of radiographic pictures of contiguous slices through a solid object such as the human body. Each picture is computed from a set of X-ray transmission measurements and represents the distribution of X-ray attenuation in the slice. The high sensitivity of the method to changes in both density and atomic number has resulted in the development of new diagnostic methods in medicine. The limitations of the method are discussed in terms of two particular kinds of application. First, those applications in which a very precise determination of density or atomic number is required, but at low spatial resolution; an example would be the determination of the uniformity of mixture of plastics or metals. The second kind of application is that requiring high spatial resolution as in the detection of cracks and the visualization of internal structures in complicated objects.

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Materials science of cells: Electron probe x-ray microanalysis and x-ray mapping in biology

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100153166 ◽

1989 ◽

Vol 47 ◽

pp. 238-239

Author(s):

Andrew P. Somlyo

Keyword(s):

Spatial Resolution ◽

Electron Probe ◽

Materials Science ◽

High Sensitivity ◽

Specimen Preparation ◽

X Ray ◽

Low Concentrations ◽

Freeze Dried ◽

And Control

The general aims of Electron Probe X-ray Microanalysis (EPMA) in Biology is similar to that in Materials Science: the determination of composition at sub-micron resolution. Special requirements include stringent precautions for specimen preparation, high sensitivity for detecting low concentrations of elements avoidance, and if not possible, quantitation and control of radiation damage, and spatial resolution of at least tens of nanometers.Special precautions for specimen preparation are dictated by the fact that biological materials exist in an aqueous milieu, and one of the most common objectives of biological EPMA is the localization and quantitation of diffusible elements. Therefore, specimen preparatory techniques must include handling of live tissues in a manner that maintains normal physiological states, and rapid freezing to trap diffusible elements in their physiological compartments. In order to obtain high spatial resolution, ultrathin cryosections have to be obtained, freeze dried and transferred to the microscope under conditions that prevent elemental translocations. Specimen temperatures during cryo-sectioning are usually at about -100°centigrade.

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Determination Of Inherent Contrast Resolution In X-Ray Imaging Using Electron Density And Effective Atomic Number Differences

10.1117/12.939310 ◽

1984 ◽

Author(s):

Frank A. DiBianca ◽

Joan E. Fetter ◽

Marion D. Barker

Keyword(s):

Electron Density ◽

Atomic Number ◽

Effective Atomic Number ◽

Contrast Resolution ◽

X Ray ◽

X Ray Imaging

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Principles of Different X-ray Phase-Contrast Imaging: A Review

Applied Sciences ◽

10.3390/app11072971 ◽

2021 ◽

Vol 11 (7) ◽

pp. 2971

Author(s):

Siwei Tao ◽

Congxiao He ◽

Xiang Hao ◽

Cuifang Kuang ◽

Xu Liu

Keyword(s):

Biological Samples ◽

Phase Contrast ◽

Recent Progress ◽

Phase Contrast Imaging ◽

Contrast Imaging ◽

X Ray ◽

X Ray Imaging ◽

Internal Structures ◽

X Ray Absorption ◽

Made In

Numerous advances have been made in X-ray technology in recent years. X-ray imaging plays an important role in the nondestructive exploration of the internal structures of objects. However, the contrast of X-ray absorption images remains low, especially for materials with low atomic numbers, such as biological samples. X-ray phase-contrast images have an intrinsically higher contrast than absorption images. In this review, the principles, milestones, and recent progress of X-ray phase-contrast imaging methods are demonstrated. In addition, prospective applications are presented.

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The Degree of Oxidation of Graphene Oxide

Nanomaterials ◽

10.3390/nano11030560 ◽

2021 ◽

Vol 11 (3) ◽

pp. 560

Author(s):

Alexandra Carvalho ◽

Mariana C. F. Costa ◽

Valeria S. Marangoni ◽

Pei Rou Ng ◽

Thi Le Hang Nguyen ◽

...

Keyword(s):

Graphene Oxide ◽

Ab Initio ◽

State Of The Art ◽

High Accuracy ◽

Precise Determination ◽

Photoemission Spectroscopy ◽

Pristine Graphene ◽

X Ray ◽

Degree Of Oxidation

We show that the degree of oxidation of graphene oxide (GO) can be obtained by using a combination of state-of-the-art ab initio computational modeling and X-ray photoemission spectroscopy (XPS). We show that the shift of the XPS C1s peak relative to pristine graphene, ΔEC1s, can be described with high accuracy by ΔEC1s=A(cO−cl)2+E0, where c0 is the oxygen concentration, A=52.3 eV, cl=0.122, and E0=1.22 eV. Our results demonstrate a precise determination of the oxygen content of GO samples.

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Visualization Ability of Phase-Contrast Synchrotron-Based X-Ray Imaging Using an X-Ray Interferometer in Soft Tissue Tumors

Technology in Cancer Research & Treatment ◽

10.1177/15330338211010121 ◽

2021 ◽

Vol 20 ◽

pp. 153303382110101

Author(s):

Thet-Thet Lwin ◽

Akio Yoneyama ◽

Hiroko Maruyama ◽

Tohoru Takeda

Keyword(s):

Computed Tomography ◽

Soft Tissue ◽

Spatial Resolution ◽

Phase Contrast ◽

Soft Tissue Tumors ◽

X Ray ◽

3 Dimensional ◽

Computed Tomography Images ◽

X Ray Imaging ◽

X Ray Computed

Phase-contrast synchrotron-based X-ray imaging using an X-ray interferometer provides high sensitivity and high spatial resolution, and it has the ability to depict the fine morphological structures of biological soft tissues, including tumors. In this study, we quantitatively compared phase-contrast synchrotron-based X-ray computed tomography images and images of histopathological hematoxylin-eosin-stained sections of spontaneously occurring rat testicular tumors that contained different types of cells. The absolute densities measured on the phase-contrast synchrotron-based X-ray computed tomography images correlated well with the densities of the nuclear chromatin in the histological images, thereby demonstrating the ability of phase-contrast synchrotron-based X-ray imaging using an X-ray interferometer to reliably identify the characteristics of cancer cells within solid soft tissue tumors. In addition, 3-dimensional synchrotron-based phase-contrast X-ray computed tomography enables screening for different structures within tumors, such as solid, cystic, and fibrous tissues, and blood clots, from any direction and with a spatial resolution down to 26 μm. Thus, phase-contrast synchrotron-based X-ray imaging using an X-ray interferometer shows potential for being useful in preclinical cancer research by providing the ability to depict the characteristics of tumor cells and by offering 3-dimensional information capabilities.

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ZnWO4 Nanoparticle Scintillators for High Resolution X-ray Imaging

Nanomaterials ◽

10.3390/nano10091721 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1721

Author(s):

Heon Yong Jeong ◽

Hyung San Lim ◽

Ju Hyuk Lee ◽

Jun Heo ◽

Hyun Nam Kim ◽

...

Keyword(s):

Particle Size ◽

Zinc Oxide ◽

High Resolution ◽

Tungsten Oxide ◽

Spatial Resolution ◽

High Spatial Resolution ◽

X Ray ◽

X Ray Imaging ◽

Average Size ◽

And Tungsten

The effect of scintillator particle size on high-resolution X-ray imaging was studied using zinc tungstate (ZnWO4) particles. The ZnWO4 particles were fabricated through a solid-state reaction between zinc oxide and tungsten oxide at various temperatures, producing particles with average sizes of 176.4 nm, 626.7 nm, and 2.127 μm; the zinc oxide and tungsten oxide were created using anodization. The spatial resolutions of high-resolution X-ray images, obtained from utilizing the fabricated particles, were determined: particles with the average size of 176.4 nm produced the highest spatial resolution. The results demonstrate that high spatial resolution can be obtained from ZnWO4 nanoparticle scintillators that minimize optical diffusion by having a particle size that is smaller than the emission wavelength.

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