scholarly journals A fast method for simultaneous reconstruction and segmentation in X-ray CT application

Author(s):  
Yiqiu Dong ◽  
Chunlin Wu ◽  
Shi Yan
Surfaces ◽  
2021 ◽  
Vol 4 (2) ◽  
pp. 106-114
Author(s):  
Yannick Hermans ◽  
Faraz Mehmood ◽  
Kerstin Lakus-Wollny ◽  
Jan P. Hofmann ◽  
Thomas Mayer ◽  
...  

Thin films of ZnWO4, a promising photocatalytic and scintillator material, were deposited for the first time using a reactive dual magnetron sputtering procedure. A ZnO target was operated using an RF signal, and a W target was operated using a DC signal. The power on the ZnO target was changed so that it would match the sputtering rate of the W target operated at 25 W. The effects of the process parameters were characterized using optical spectroscopy, X-ray diffraction, and scanning electron microscopy, including energy dispersive X-ray spectroscopy as well as X-ray photoelectron spectroscopy. It was found that stoichiometric microcrystalline ZnWO4 thin films could be obtained, by operating the ZnO target during the sputtering procedure at a power of 55 W and by post-annealing the resulting thin films for at least 10 h at 600 °C. As FTO coated glass substrates were used, annealing led as well to the incorporation of Na, resulting in n+ doped ZnWO4 thin films.


2013 ◽  
Vol 2013 ◽  
pp. 1-4 ◽  
Author(s):  
M. Kooti ◽  
A. Naghdi Sedeh

A new and simple method was applied for the synthesis of ZnO nanoparticles with an average size of 20 nm. In this microwave-assisted combustion method, glycine as a fuel and zinc nitrate as precursor were used. The final product was obtained very fast with high yield and purity. The synthesized nanoscale ZnO was characterized by X-ray Diffraction (XRD), Energy Dispersive X-ray spectroscopy (EDX), and Fourier transform infrared spectroscopy (FT-IR). The size and morphology of the ZnO nanoparticles have been determined by field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) techniques. This is a simple and fast method for the preparation of ZnO nanoparticles with no need for expensive materials or complicated treatments.


2014 ◽  
Vol 98 ◽  
pp. 189-200 ◽  
Author(s):  
Hua Zhang ◽  
Luping Xu ◽  
Shibin Song ◽  
Rong Jiao
Keyword(s):  
X Ray ◽  

2019 ◽  
Vol 180 ◽  
pp. 105201 ◽  
Author(s):  
Ignazio Allegretta ◽  
Biancamaria Ciasca ◽  
Maria D.R. Pizzigallo ◽  
Veronica M.T. Lattanzio ◽  
Roberto Terzano

2016 ◽  
Vol 49 (2) ◽  
pp. 544-555 ◽  
Author(s):  
Nicola Viganò ◽  
Laura Nervo ◽  
Lorenzo Valzania ◽  
Gaurav Singh ◽  
Michael Preuss ◽  
...  

Three-dimensional X-ray orientation microscopy based on X-ray full-field imaging techniques such as diffraction contrast tomography is a challenging task when it comes to materials displaying non-negligible intragranular orientation spread and/or intricate grain microstructures as a result of plastic deformation and deformation twinning. As shown in this article, the optimization of the experimental conditions and a number of modifications of the data analysis routines enable detection and three-dimensional reconstruction of twin lamellae down to micrometre thickness, as well as more accurate three-dimensional reconstruction of grains displaying intragranular orientation spreads of up to a few degrees. The reconstruction of spatially resolved orientation maps becomes possible through the use of a recently introduced six-dimensional reconstruction framework, which has been further extended in order to enable simultaneous reconstruction of parent and twin orientations and to account for the finite impulse response of the X-ray imaging detector. The simultaneous reconstruction of disjoint orientation domains requires appropriate scaling of the scattering intensities based on structure and Lorentz factors and yields three-dimensional reconstructions with comparable density values for all the grains. This in turn enables the use of a global intensity-guided assembly procedure and avoids problems related to the single-grain thresholding procedure used previously. Last but not least, carrying out a systematic search over the list of known twin variants (forward modelling) for each of the indexed parent grains, it is possible to identify additional twins which have been left undetected at the previous stage of grain indexing based on diffraction spot peak positions. The enhanced procedure has been tested on a 1% deformed specimen made from a Ti–4% Al alloy and the result has been cross-validated against a two-dimensional electron backscatter diffraction orientation map acquired on one of the lateral sample surfaces.


2015 ◽  
Vol 71 (a1) ◽  
pp. s287-s288
Author(s):  
Sigmund H. Neher ◽  
Chaouachi Marwen ◽  
Falenty Andrzej ◽  
Klein Helmut ◽  
Werner F. Kuhs

2018 ◽  
Vol 25 (6) ◽  
pp. 1893-1894 ◽  
Author(s):  
Maarten Houlleberghs ◽  
Johan A. Martens ◽  
Eric Breynaert

A low-cost, flexible and fast method to create disposable sample cells suitable for in situ catalytic or material synthesis studies based on standard quartz capillaries, heat-shrinkable tubing and standard Swagelok components is described.


Author(s):  
Vladimir A. Terekhov ◽  
Evgeny I. Terukov ◽  
Yury K. Undalov ◽  
Konstantin A. Barkov ◽  
Igor E. Zanin ◽  
...  

Amorphous SiOx films with silicon nanoclusters are a new interesting material from the standpoint of the physics, technology, and possible practical applications, since such films can exhibit photoluminescence due to size quantization. Moreover, the optical properties of these structures can be controlled by varying the size and the content of silicon nanoclusters in the SiOx film, as well as by transforming nanoclusters into nanocrystals by means of high-temperature annealing. However, during the annealing of nonstoichiometric silicon oxide, significant changes can occur in the phase composition and the structure of the films. The results of investigations on the crystallization of silicon nanoclusters in a SiOx matrix have shownthat, even a very fast method of annealing using PPA leads to the formation of large silicon crystallites. This also causes the crystallization of at least a part of the oxide phase in the form of silicon hydroxide H6O7Si2. Moreover, in films with an initial content of pure silicon nanoclusters ≤ 50%, during annealing a part of the silicon is spent on the formation of oxide, and part of it is spent on the formation of silicon crystals. While in a film with an initial concentration of silicon nanoclusters ≥ 53%, on the contrary, upon annealing, there occurs a partial transition of silicon from the oxide phase to the growth ofSi crystals        Reference 1. Undalov Y. K., Terukov E. I., Silicon nanoclustersncl-Si in a hydrogenated amorphous silicon suboxidematrix a-SiOx:H (0 < x < 2). Semiconductors. 2015;49(7):867- 878. DOI: https://doi.org/10.1134/S10637826150702222. Kim K. H., Johnson E. V., Kazanskii A. G.,Khenkin M. V., Roca P. Unravelling a simple methodfor the low temperature synthesis of siliconnanocrystals and monolithic nanocrystalline thinfilms. Scientific Reports. 2017;7(1) DOI: https://doi.org/10.1038/srep405533. Undalov Y. K., Terukov E. I., Trapeznikova I. N.Formation of ncl-Si in the amorphous matrix a-SiOx-:H located near the anode and on the cathode, usinga time-modulated DC plasma with the (SiH4–Ar–O2)gas phase (Co2 = 21.5 mol%). Semiconductors.2019;53(11): 1514–1523. DOI: https://doi.org/10.1134/S10637826191102284. Terekhov V. A., Terukov E. I., Undalov Y. K.,Parinova E. V., Spirin D. E., Seredin P. V., Minakov D. A.,Domashevskaya E. P. Composition and optical propertiesof amorphous a-SiOx:H films with silicon nanoclusters.Semiconductors. 2016;50(2): 212–216. DOI:https://doi.org/10.1134/S10637826160202515. Terekhov V. A., Turishchev S. Y., Kashkarov V. M.,Domashevskaya E. P., Mikhailov A. N., Tetel’baum D. I.Silicon nanocrystals in SiO2 matrix obtained by ionimplantation under cyclic dose accumulation. PhysicaE: Low-dimensional Systems and Nanostructures.2007;38(1-2): 16–20. DOI: https://doi.org/10.1016/j.physe.2006.12.0306. Terekhov V. A., Turishchev S. Y., Pankov K. N.,Zanin I. E., Domashevskaya E. P., Tetelbaum D. I.,Mikhailov A. N., Belov A. I., Nikolichev D. E., Zubkov S. Y.XANES, USXES and XPS investigations of electronenergy and atomic structure peculiarities of the siliconsuboxide thin film surface layers containing Si nanocrystals.Surface and Interface Analysis. 2010;42(6-7):891–896. DOI: https://doi.org/10.1002/sia.33387. Terekhov V. A., Turishchev S. Y., Pankov K. N.,Zanin I. E., Domashevskaya E. P., Tetelbaum, MikhailovA. N., Belov A. I., Nikolichev D. E. Synchrotron investigationsof electronic and atomic-structure peculiaritiesfor silicon-oxide films’ surface layers containingsilicon nanocrystals. Journal of Surface Investigation.X-ray, Synchrotron and Neutron Techniques. 2011;5(5):958–967. DOI: https://doi.org/10.1134/S102745101110020X8. Sato K., Izumi T., Iwase M., Show Y., Morisaki H.,Yaguchi T., Kamino T. Nucleation and growth of nanocrystallinesilicon studied by TEM, XPS and ESR.Applied Surface Science. 2003;216 (1-4): 376–381. DOI:https://doi.org/10.1016/S0169-4332(03)00445-89. Ledoux G., Gong J., Huisken F., Guillois O., ReynaudC. Photoluminescence of size-separated siliconnanocrystals: Confirmation of quantum confinement.Applied Physics Letters. 2002;80(25): 4834–4836. DOI:https://doi.org/10.1063/1.148530210. Patrone L., Nelson D., Safarov V. I., Sentis M.,Marine W., Giorgio S. Photoluminescence of siliconnanoclusters with reduced size dispersion producedby laser ablation. Journal of Applied Physics. 2000;87(8):3829–3837. DOI: https://doi.org/10.1063/1.37242111. Takeoka S., Fujii M., Hayashi S. Size-dependentphotoluminescence from surface-oxidized Si nanocrystalsin a weak confinement regime. Physical ReviewB. 2000;62(24): 16820–16825. DOI: https://doi.org/10.1103/PhysRevB.62.1682012. Ievlev V. M. Activation of solid-phase processesby radiation of gas-discharge lamps, Russian ChemicalReviews. 2013;82(9): 815–834. DOI: https://doi.org/10.1070/rc2013v082n09abeh00435713. Zimkina T. M., Fomichev V. A. Ultrasoft X-Rayspectroscopy. Leningrad: Leningrad State UniversityPubl.; 1971. 132 p.14. Wiech G., Feldhütter H. O., Šimůnek A. Electronicstructure of amorphous SiOx:H alloy filmsstudied by X-ray emission spectroscopy: Si K, Si L, andO K emission bands. Physical Review B. 1993;47(12):6981–6989. DOI: https://doi.org/10.1103/Phys-RevB.47.698115. Domashevskaya E. P., Peshkov Y. A., TerekhovV. A., Yurakov Y. A., Barkov K. A., Phase compositionof the buried silicon interlayers in the amorph o u s m u l t i l a y e r n a n o s t r u c t u r e s[(Co45Fe45Zr10)/a-Si:H]41 and [(Co45Fe45Zr10)35(Al2O3)65/a-Si:H]41. Surface and Interface Analysis.2018;50(12-13): 1265–1270. DOI: https://doi.org/10.1002/sia.651516. Terekhov V. A., Kashkarov V. M., ManukovskiiE. Yu., Schukarev A. V., Domashevskaya E. P.Determination of the phase composition of surfacelayers of porous silicon by ultrasoft X-ray spectroscopyand X-ray photoelectron spectroscopy techniques.Journal of Electron Spectroscopy and Related Phenomena.2001;114–116: 895–900. DOI: https://doi.org/10.1016/S0368-2048(00)00393-517. JCPDS-International Centre for DiffractionData ICDD PDF-2, (n.d.) card No 01-077-2110.18. JCPDS-International Centre for DiffractionData ICDD PDF-2, (n.d.) card No 00-050-0438.


1987 ◽  
Vol 31 ◽  
pp. 423-430 ◽  
Author(s):  
P. Caussin ◽  
J. Nusinovici ◽  
D.W. Beard

AbstractA Search/Matcti program lias 'beea written for the IBM PC AT computer that is capable of -using "background - subtracted, digitized 2-ray powder diffraction scans as inputs in addition to the d/I data traditionally used. This novel procedure has proved especially effective when numerous unresolved lines are present in the pattern. The method is also less demanding of data quality thaii the peak location programs. The program may he extended to searching & data "base of digitized standard patterns.The program, has several parameters that can- "be adjusted, including chemistry. The results from the Johnson/Vand list type of output are directly accessible to the interactive graphics program. This gives the diffraction!st a fast method for verifying the phase identification. Because of the speed of fixed point computation techniques, the 52,791 pattern file can be scanned in about 90 seconds.This paper will illustrate the utility of the program.


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