scholarly journals Three Dimensional Atomic Image of TlInSe2 by X-ray Fluorescence Holography

2011 ◽  
Vol 9 ◽  
pp. 273-276 ◽  
Author(s):  
Kojiro Mimura ◽  
Shinya Hosokawa ◽  
Naohisa Happo ◽  
Wen Hu ◽  
Kouichi Hayashi ◽  
...  
Keyword(s):  
X Ray ◽  
2005 ◽  
Vol 44 (2) ◽  
pp. 1011-1012 ◽  
Author(s):  
Shinya Hosokawa ◽  
Naohisa Happo ◽  
Koichi Hayashi ◽  
Yukio Takahashi ◽  
Tōru Ozaki ◽  
...  

Author(s):  
Atsushi Kubota ◽  
Tomohiro Matsushita ◽  
Naohisa Happo

AbstractX-ray fluorescence holography is a three-dimensional middle range local structure analysis method, which can provide three-dimensional atomic images around specific elements within a radius of a few nanometers. Three-dimensional atomic images are reconstructed by applying discrete Fourier transform (DFT) to hologram data. Presently, it takes long time to process this DFT. In this study, the DFT program is parallelized by using a parallel programming language XcalableMP. The DFT process, whose input is 21 holograms data of 179 × 360 points and output is a three-dimensional atomic image of 1923 points, is executed on PC cluster which consists of 8 nodes of Intel Xeon X5660 processors and 96 cores in total and we confirmed that the parallelized DFT execution is 94 times faster than the sequential execution.


2004 ◽  
Vol 19 (1) ◽  
pp. 77-80 ◽  
Author(s):  
Y. Takahashi ◽  
K. Hayashi ◽  
E. Matsubara

The X-ray fluorescence holography (XFH) method has drawn the attention of many researchers as a novel experimental technique for imaging a three-dimensional local atomic structure around a certain element in a single crystal. Synchrotron radiation (SR) has been mainly used for the measurements because of extremely weak signals that are about 0.3% of isotropic fluorescent radiation. The measurements limited to the use of a SR source clearly hinder from increasing the number of the users. Thus, we developed a laboratory XFH equipment with a conventional X-ray source by using a singly bent graphite monochromator with a large curvature and X-ray detector for a high counting rate. With this equipment, we have successfully demonstrated that high-quality hologram data of a gold single crystal almost equivalent to those with a SR source are obtained. Four different holograms are recorded in the normal and inverse XFH modes. An atomic image reconstructed from these holograms patterns shows a distinct atomic image of Au


2018 ◽  
Vol 61 (12) ◽  
pp. 784-789
Author(s):  
Shinya HOSOKAWA ◽  
Kouichi HAYASHI ◽  
Koji KIMURA ◽  
Naohisa HAPPO ◽  
Tomohiro MATSUSHITA
Keyword(s):  
X Ray ◽  

2016 ◽  
Vol 230 (4) ◽  
Author(s):  
Tomohiro Matsushita ◽  
Atsushi Kubota ◽  
Naohisa Happo ◽  
Kazuto Akagi ◽  
Natsuhiko Yoshinaga ◽  
...  

AbstractA fast calculation algorithm for three-dimensional atomic image reconstruction from X-ray fluorescence holography (Barton's method) is described. This method employs HEALPix, an algorithm that is used to subdivide a spherical surface in which each pixel covers an identical surface area. Using this algorithm, the computing time for atomic image reconstruction is reduced by a factor of 14.5. The time can be reduced further by parallel processing and an optimization of the resolution parameter of HEALPix.


Author(s):  
James A. Lake

The understanding of ribosome structure has advanced considerably in the last several years. Biochemists have characterized the constituent proteins and rRNA's of ribosomes. Complete sequences have been determined for some ribosomal proteins and specific antibodies have been prepared against all E. coli small subunit proteins. In addition, a number of naturally occuring systems of three dimensional ribosome crystals which are suitable for structural studies have been observed in eukaryotes. Although the crystals are, in general, too small for X-ray diffraction, their size is ideal for electron microscopy.


Author(s):  
S. Cusack ◽  
J.-C. Jésior

Three-dimensional reconstruction techniques using electron microscopy have been principally developed for application to 2-D arrays (i.e. monolayers) of biological molecules and symmetrical single particles (e.g. helical viruses). However many biological molecules that crystallise form multilayered microcrystals which are unsuitable for study by either the standard methods of 3-D reconstruction or, because of their size, by X-ray crystallography. The grid sectioning technique enables a number of different projections of such microcrystals to be obtained in well defined directions (e.g. parallel to crystal axes) and poses the problem of how best these projections can be used to reconstruct the packing and shape of the molecules forming the microcrystal.Given sufficient projections there may be enough information to do a crystallographic reconstruction in Fourier space. We however have considered the situation where only a limited number of projections are available, as for example in the case of catalase platelets where three orthogonal and two diagonal projections have been obtained (Fig. 1).


Author(s):  
H.W. Deckman ◽  
B.F. Flannery ◽  
J.H. Dunsmuir ◽  
K.D' Amico

We have developed a new X-ray microscope which produces complete three dimensional images of samples. The microscope operates by performing X-ray tomography with unprecedented resolution. Tomography is a non-invasive imaging technique that creates maps of the internal structure of samples from measurement of the attenuation of penetrating radiation. As conventionally practiced in medical Computed Tomography (CT), radiologists produce maps of bone and tissue structure in several planar sections that reveal features with 1mm resolution and 1% contrast. Microtomography extends the capability of CT in several ways. First, the resolution which approaches one micron, is one thousand times higher than that of the medical CT. Second, our approach acquires and analyses the data in a panoramic imaging format that directly produces three-dimensional maps in a series of contiguous stacked planes. Typical maps available today consist of three hundred planar sections each containing 512x512 pixels. Finally, and perhaps of most import scientifically, microtomography using a synchrotron X-ray source, allows us to generate maps of individual element.


Author(s):  
Sterling P. Newberry

The beautiful three dimensional representation of small object surfaces by the SEM leads one to search for ways to open up the sample and look inside. Could this be the answer to a better microscopy for gross biological 3-D structure? We know from X-Ray microscope images that Freeze Drying and Critical Point Drying give promise of adequately preserving gross structure. Can we slice such preparations open for SEM inspection? In general these preparations crush more readily than they slice. Russell and Dagihlian got around the problem by “deembedding” a section before imaging. This some what defeats the advantages of direct dry preparation, thus we are reluctant to accept it as the final solution to our problem. Alternatively, consider fig 1 wherein a freeze dried onion root has a window cut in its surface by a micromanipulator during observation in the SEM.


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