scholarly journals Orientation determination in single-particle x-ray coherent diffraction imaging experiments

2013 ◽  
Vol 46 (16) ◽  
pp. 164013 ◽  
Author(s):  
O M Yefanov ◽  
I A Vartanyants
2018 ◽  
Vol 74 (5) ◽  
pp. 512-517
Author(s):  
Miklós Tegze ◽  
Gábor Bortel

In coherent-diffraction-imaging experiments X-ray diffraction patterns of identical particles are recorded. The particles are injected into the X-ray free-electron laser (XFEL) beam in random orientations. If the particle has symmetry, finding the orientation of a pattern can be ambiguous. With some modifications, the correlation-maximization method can find the relative orientations of the diffraction patterns for the case of symmetric particles as well. After convergence, the correlation maps show the symmetry of the particle and can be used to determine the symmetry elements and their orientations. The C factor, slightly modified for the symmetric case, can indicate the consistency of the assembled three-dimensional intensity distribution.


2012 ◽  
Vol 46 (1) ◽  
pp. 234-241 ◽  
Author(s):  
Chae Un Kim ◽  
Jennifer L. Wierman ◽  
Richard Gillilan ◽  
Enju Lima ◽  
Sol M. Gruner

High-pressure cryocooling has been developed as an alternative method for cryopreservation of macromolecular crystals and successfully applied for various technical and scientific studies. The method requires the preservation of crystal hydration as the crystal is pressurized with dry helium gas. Previously, crystal hydration was maintained either by coating crystals with a mineral oil or by enclosing crystals in a capillary which was filled with crystallization mother liquor. These methods are not well suited to weakly diffracting crystals because of the relatively high background scattering from the hydrating materials. Here, an alternative method of crystal hydration, called capillary shielding, is described. The specimen is kept hydratedviavapor diffusion in a shielding capillary while it is being pressure cryocooled. After cryocooling, the shielding capillary is removed to reduce background X-ray scattering. It is shown that, compared to previous crystal-hydration methods, the new hydration method produces superior crystal diffraction with little sign of crystal damage. Using the new method, a weakly diffracting protein crystal may be properly pressure cryocooled with little or no addition of external cryoprotectants, and significantly reduced background scattering can be observed from the resulting sample. Beyond the applications for macromolecular crystallography, it is shown that the method has great potential for the preparation of noncrystalline hydrated biological samples for coherent diffraction imaging with future X-ray sources.


2011 ◽  
Vol 31 (4) ◽  
pp. 0418001
Author(s):  
谭兴兴 Tan Xingxing ◽  
刘海岗 Liu Haigang ◽  
郭智 Guo Zhi ◽  
吴衍青 Wu Yanqing ◽  
许子健 Xu Zijian ◽  
...  

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Yudong Yao ◽  
Yi Jiang ◽  
Jeffrey A. Klug ◽  
Michael Wojcik ◽  
Evan R. Maxey ◽  
...  

Abstract X-ray ptychography is a rapidly developing coherent diffraction imaging technique that provides nanoscale resolution on extended field-of-view. However, the requirement of coherence and the scanning mechanism limit the throughput of ptychographic imaging. In this paper, we propose X-ray ptychography using multiple illuminations instead of single illumination in conventional ptychography. Multiple locations of the sample are simultaneously imaged by spatially separated X-ray beams, therefore, the obtained field-of-view in one scan can be enlarged by a factor equal to the number of illuminations. We have demonstrated this technique experimentally using two X-ray beams focused by a house-made Fresnel zone plate array. Two areas of the object and corresponding double illuminations were successfully reconstructed from diffraction patterns acquired in one scan, with image quality similar with those obtained by conventional single-beam ptychography in sequence. Multi-beam ptychography approach increases the imaging speed, providing an efficient way for high-resolution imaging of large extended specimens.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Ni Li ◽  
Maxime Dupraz ◽  
Longfei Wu ◽  
Steven J. Leake ◽  
Andrea Resta ◽  
...  

Abstract We explore the use of continuous scanning during data acquisition for Bragg coherent diffraction imaging, i.e., where the sample is in continuous motion. The fidelity of continuous scanning Bragg coherent diffraction imaging is demonstrated on a single Pt nanoparticle in a flow reactor at $$400\,^\circ \hbox {C}$$ 400 ∘ C in an Ar-based gas flowed at 50 ml/min. We show a reduction of 30% in total scan time compared to conventional step-by-step scanning. The reconstructed Bragg electron density, phase, displacement and strain fields are in excellent agreement with the results obtained from conventional step-by-step scanning. Continuous scanning will allow to minimise sample instability under the beam and will become increasingly important at diffraction-limited storage ring light sources.


2019 ◽  
Vol 99 (5) ◽  
Author(s):  
S. Maddali ◽  
M. Allain ◽  
W. Cha ◽  
R. Harder ◽  
J.-S. Park ◽  
...  

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
M. Zürch ◽  
R. Jung ◽  
C. Späth ◽  
J. Tümmler ◽  
A. Guggenmos ◽  
...  

Nanoscale ◽  
2018 ◽  
Vol 10 (6) ◽  
pp. 2820-2824 ◽  
Author(s):  
Chi-Feng Huang ◽  
Keng S. Liang ◽  
Tsui-Ling Hsu ◽  
Tsung-Tse Lee ◽  
Yi-Yun Chen ◽  
...  

Coherent diffraction imaging (CDI) with X-ray free electron laser (X-FEL) detected individual blank (left) and drug containing (right, with Doxorubicin nanorod) liposome nanoparticles in solution.


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