Статті в журналах: "Selected Area Electron Diffraction (SAED) Patterns"

1

Liu, Delu. "Features of the ISO-25498: Method of Selected Area Electron Diffraction Analysis in Transmission Electron Microscopy." Microscopy and Microanalysis 19, S5 (August 2013): 207–9. http://dx.doi.org/10.1017/s1431927613012671.

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AbstractInternational standard ISO-25498 specifies the method of selected area electron diffraction (SAED) analysis in TEM. It is applicable to the acquisition of SAED patterns, indexing the patterns and calibration of diffraction constant. Several features of this standard are introduced. As an example of the applications, phosphide with nanometer scale in a low-carbon steel produced by compact strip production process was analyzed by SAED and EDX. The phosphide precipitates in the steel are identified as MxP, where x is 2–3 and M is Fe, Ti, Cr, or Ni. It possesses a hexagonal lattice with lattice parameter a = 0.609 nm and c = 0.351 nm.

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2

Slouf, Miroslav, Radim Skoupy, Ewa Pavlova, and Vladislav Krzyzanek. "Powder Nano-Beam Diffraction in Scanning Electron Microscope: Fast and Simple Method for Analysis of Nanoparticle Crystal Structure." Nanomaterials 11, no. 4 (April 9, 2021): 962. http://dx.doi.org/10.3390/nano11040962.

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We introduce a novel scanning electron microscopy (SEM) method which yields powder electron diffraction patterns. The only requirement is that the SEM microscope must be equipped with a pixelated detector of transmitted electrons. The pixelated detectors for SEM have been commercialized recently. They can be used routinely to collect a high number of electron diffraction patterns from individual nanocrystals and/or locations (this is called four-dimensional scanning transmission electron microscopy (4D-STEM), as we obtain two-dimensional (2D) information for each pixel of the 2D scanning array). Nevertheless, the individual 4D-STEM diffractograms are difficult to analyze due to the random orientation of nanocrystalline material. In our method, all individual diffractograms (showing randomly oriented diffraction spots from a few nanocrystals) are combined into one composite diffraction pattern (showing diffraction rings typical of polycrystalline/powder materials). The final powder diffraction pattern can be analyzed by means of standard programs for TEM/SAED (Selected-Area Electron Diffraction). We called our new method 4D-STEM/PNBD (Powder NanoBeam Diffraction) and applied it to three different systems: Au nano-islands (well diffracting nanocrystals with size ~20 nm), small TbF3 nanocrystals (size < 5 nm), and large NaYF4 nanocrystals (size > 100 nm). In all three cases, the STEM/PNBD results were comparable to those obtained from TEM/SAED. Therefore, the 4D-STEM/PNBD method enables fast and simple analysis of nanocrystalline materials, which opens quite new possibilities in the field of SEM.

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3

Macicek, Josef. "Phase Microidentification from Selected Area Electron Diffraction (SAED) and Energy Dispersive Spectroscopy (EDS) Data." Advances in X-ray Analysis 35, A (1991): 687–91. http://dx.doi.org/10.1154/s0376030800009423.

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AbstractTwo-dimensional geometry information contained in SAED spot patterns augmented with EDS elemental data is employed in a computerized phase identification of microcrystalline particles. The initial chemistry screening of a laboratory managed database using the 'bitmap' concept is followed by a geometry search/match treating of the spot patterns as planar sections through the reciprocal lattice of a candidate phase. The identification is selective, fast, and yields to a complete automatization,

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4

Nakamura, Junya, Kenji Matsuda, Yoshio Nakamura, Tatsuo Sato, and Susumu Ikeno. "HRTEM Observation of Rod-Shape Precipitates in Al-Mg-Si-Ag Alloy Aged at 523 K." Materials Science Forum 561-565 (October 2007): 243–46. http://dx.doi.org/10.4028/www.scientific.net/msf.561-565.243.

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The purpose of this study is to identify the crystal structure of metastable phase in Ag added Al-Mg-Si alloy to compare the formation of β’-phases in Al-Mg-Si alloys without Ag, using images of high resolution transmission electron microscope (HRTEM), selected area electron diffraction (SAED) patterns and an energy dispersive X-ray spectroscopy (EDS). The result of SAED patterns and HRTEM images have been simulated and compared with images then SAED patterns obtained from actual precipitates. SAED patterns and HRTEM images obtained from metastable phase in the Ag added Al-Mg-Si alloy showed similar to those of β’-phase in Al-Mg-Si alloy without Ag and the lattice spacings changed because of the effect of Ag.

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5

Slouf, Miroslav, Radim Skoupy, Ewa Pavlova, and Vladislav Krzyzanek. "High Resolution Powder Electron Diffraction in Scanning Electron Microscopy." Materials 14, no. 24 (December 9, 2021): 7550. http://dx.doi.org/10.3390/ma14247550.

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A modern scanning electron microscope equipped with a pixelated detector of transmitted electrons can record a four-dimensional (4D) dataset containing a two-dimensional (2D) array of 2D nanobeam electron diffraction patterns; this is known as a four-dimensional scanning transmission electron microscopy (4D-STEM). In this work, we introduce a new version of our method called 4D-STEM/PNBD (powder nanobeam diffraction), which yields high-resolution powder diffractograms, whose quality is fully comparable to standard TEM/SAED (selected-area electron diffraction) patterns. Our method converts a complex 4D-STEM dataset measured on a nanocrystalline material to a single 2D powder electron diffractogram, which is easy to process with standard software. The original version of 4D-STEM/PNBD method, which suffered from low resolution, was improved in three important areas: (i) an optimized data collection protocol enables the experimental determination of the point spread function (PSF) of the primary electron beam, (ii) an improved data processing combines an entropy-based filtering of the whole dataset with a PSF-deconvolution of the individual 2D diffractograms and (iii) completely re-written software automates all calculations and requires just a minimal user input. The new method was applied to Au, TbF3 and TiO2 nanocrystals and the resolution of the 4D-STEM/PNBD diffractograms was even slightly better than that of TEM/SAED.

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6

Odlyzko, Michael L., and K. Andre Mkhoyan. "Identifying Hexagonal Boron Nitride Monolayers by Transmission Electron Microscopy." Microscopy and Microanalysis 18, no. 3 (April 12, 2012): 558–67. http://dx.doi.org/10.1017/s143192761200013x.

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AbstractMultislice simulations in the transmission electron microscope (TEM) were used to examine changes in annular-dark-field scanning TEM (ADF-STEM) images, conventional bright-field TEM (BF-CTEM) images, and selected-area electron diffraction (SAED) patterns as atomically thin hexagonal boron nitride (h-BN) samples are tilted up to 500 mrad off of the [0001] zone axis. For monolayer h-BN the contrast of ADF-STEM images and SAED patterns does not change with tilt in this range, while the contrast of BF-CTEM images does change; h-BN multilayer contrast varies strongly with tilt for ADF-STEM imaging, BF-CTEM imaging, and SAED. These results indicate that tilt series analysis in ADF-STEM image mode or SAED mode should permit identification of h-BN monolayers from raw TEM data as well as from quantitative post-processing.

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7

Van Buskirk, Peter C., Robin Gardiner, Peter S. Kirlin, and Steven Nutt. "Reduced-pressure MOCVD of highly crystalline BaTiO3 thin films." Journal of Materials Research 7, no. 3 (March 1992): 542–45. http://dx.doi.org/10.1557/jmr.1992.0542.

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Epitaxial BaTi3 films have been grown on NdGaO3 [100] substrates by reduced pressure MOCVD for the first time. The substrate temperature was 1000 °C and the total pressure was 4 Torr. Electron and x-ray diffraction measurements indicate highly textured, single phase films on the NdGaO3 substrate which are predominantly [100], with [110] also present. TEM and selected area electron diffraction (SAED) indicate two specific orientational relationships between the [110] and the [001] diffraction patterns.

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8

Li, Qingyun, Lingyu Liu, Zihua Wang, and Xuezhong Wang. "Continuous Hydrothermal Flow Synthesis and Characterization of ZrO2 Nanoparticles Doped with CeO2 in Supercritical Water." Nanomaterials 12, no. 4 (February 17, 2022): 668. http://dx.doi.org/10.3390/nano12040668.

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A confined jet mixing reactor operated in continuous hydrothermal flow synthesis was investigated for the synthesis of CeO2-ZrO2 (CZ) nanoparticles. The obtained ultrafine powders were characterized using scanning electron microscopy–energy dispersive spectrometry (SEM-EDS), inductively coupled plasma–atomic emission spectroscopy (ICP-AES), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction analysis (XRD), transmission electron microscopy (TEM) coupled with selected area electron diffraction (SAED), a BET (Brunauer-Emmett-Teller)-specific surface area test and pore analysis, oxygen storage capacity (OSC) test, and a H2 temperature programmed reduction (H2-TPR) test. The XRD results show that all samples were composed of high-purity cubic CZ nanoparticles. High resolution transmission electron microscope (HR-TEM) analysis showed that CZ nanoparticles with uniform size and shape distributions were obtained in this investigation. The d-spacing values, determined based on the TEM-selected area electron diffraction (SAED) patterns, were in good agreements with the reference data. BET results showed that the prepared CZ samples had large specific surface areas. Pore volume and size distribution were obtained by pore analysis. Oxygen pulse adsorption technology was used to test the oxygen storage capacity of the sample. The redox capacity of the CZ material was determined by a H2 temperature-programmed reduction test.

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9

Lábár, János L. "Electron Diffraction Based Analysis of Phase Fractions and Texture in Nanocrystalline Thin Films, Part I: Principles." Microscopy and Microanalysis 14, no. 4 (July 4, 2008): 287–95. http://dx.doi.org/10.1017/s1431927608080380.

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A method for phase analysis, similar to the Rietveld method in X-ray diffraction, was not developed for electron diffraction (ED) in the transmission electron microscope (TEM), mainly due to the dynamic nature of ED. Nowadays, TEM laboratories encounter many thin samples with grain size in the 1–30 nm range, not too far from the kinematic ED conditions. This article describes a method that performs (semi)quantitative phase analysis for nanocrystalline samples from selected area electron diffraction (SAED) patterns. Fractions of the different nanocrystalline components are determined from rotationally symmetric ring patters. Both randomly oriented nanopowders and textured nanopowders, observed from the direction of the texture axis produce such SAED patterns. The textured fraction is determined as a separate component by fitting the spectral components, calculated for the previously identified phases with a priori known structures, to the measured distribution. The Blackman correction is applied to the set of kinematic diffraction lines to take into account dynamic effects for medium grain size. Parameters of the peak shapes and the other experimental parameters are refined by exploring the parameter space with the help of the Downhill-SIMPLEX. Part I presents the principles, while future publication of Parts II and III will elaborate on current implementation and will demonstrate its usage by examples, respectively.

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10

KANG, YOUNG SOO, and DONG RI ZHANG. "SYNTHESIS AND CHARACTERIZATION OF TITANIUM DIOXIDE DOPED WITH Sc3+ IONS." International Journal of Nanoscience 05, no. 02n03 (April 2006): 351–57. http://dx.doi.org/10.1142/s0219581x06004462.

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Nanoparticles of titanium dioxide ( TiO 2) doped with 5 at.% Sc 3+ ions were synthesized using the sol–gel method and calcined at 500°C to obtain better anatase phase. The crystal structures of the doped TiO 2 nanoparticles were characterized by X-ray powder diffraction (XRD), Raman, UV-vis, FT-IR spectroscopy, high resolution transmission electron microscopy (HRTEM) and selected-area electron diffraction (SAED). XRD patterns and Raman spectra of TiO 2 + 5 at.% Sc -500°C show the anatase phase and the average particle size of the sample calculated from XRD patterns was determined as 5.9 nm. Well-resolved rings of SAED of TiO 2 doped with Sc 3+ ions are easily indexed to those from XRD pattern. HRTEM shows the well-defined lattice fringes and the lattice spacing measured from HRTEM is 0.33 nm, which is in well agreement with the distance between the (101) planes in anatase TiO 2. Energy-dispersive X-ray (EDX) spectrum of the doped TiO 2 confirms the presence of Sc element in the TiO 2 matrix.

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11

POKAIPISIT, ARTORN, SURASING CHAIYAKUN, PICHET LIMSUWAN, and BOONLAER NGOTAWORNCHAI. "NANOSTRUCTURE OF TiO2 THIN FILMS PREPARED BY UNBALANCED MAGNETRON SPUTTERING." International Journal of Modern Physics B 23, no. 10 (April 20, 2009): 2395–403. http://dx.doi.org/10.1142/s0217979209052297.

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In this study, titanium dioxide ( TiO 2) thin films were deposited on unheated glass substrates using an unbalanced magnetron sputtering system with different deposition times of 25, 35 and 45 min, respectively. The structure and surface morphology of TiO 2 thin films were characterized by atomic force microscopy (AFM) and transmission electron microscopy (TEM) with selected-area electron diffraction (SAED). It was found that the crystallite size of TiO 2 thin films was in the range of 10–20 nm, and the surface roughness was 1–3 nm. The SAED patterns show that the phase of TiO 2 thin films obtained in this study is anatase phase.

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12

Lábár, János L. "Electron Diffraction Based Analysis of Phase Fractions and Texture in Nanocrystalline Thin Films, Part II: Implementation." Microscopy and Microanalysis 15, no. 1 (January 15, 2009): 20–29. http://dx.doi.org/10.1017/s1431927609090023.

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AbstractThis series of articles describes a method that performs (semi)quantitative phase analysis for nanocrystalline transmission electron microscope samples from selected area electron diffraction (SAED) patterns. Volume fractions of phases and their textures are obtained separately in the method. First, the two-dimensional SAED pattern is converted into an X-ray diffraction–like one-dimensional distribution. Volume fractions of the nanocrystalline components are determined by fitting the spectral components, calculated for the previously identified phases with a priori known structures. Blackman correction is also applied to take into account dynamic effects for medium grain sizes. Peak shapes and experimental parameters (camera length, etc.) are refined during the fitting iterations. Parameter space is explored with the help of the Downhill-SIMPLEX algorithm. Part I presented the principles, while Part II now elaborates current implementation, and Part III will demonstrate its usage by examples. The method is implemented in a computer program that runs under the Windows operating system on IBM PC compatible machines.

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13

Martin, David C., and Jun Liao. "Dynamic low-dose electron diffraction and imaging of phase transitions in polymers." Proceedings, annual meeting, Electron Microscopy Society of America 51 (August 1, 1993): 890–91. http://dx.doi.org/10.1017/s0424820100150289.

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By careful control of the electron beam it is possible to simultaneously induce and observe the phase transformation from monomer to polymer in certain solid-state polymcrizable diacetylenes. The continuous change in the crystal structure from DCHD diacetylene monomer (a=1.76 nm, b=1.36 nm, c=0.455 nm, γ=94 degrees, P2l/c) to polymer (a=1.74 nm, b=1.29 nm, c=0.49 nm, γ=108 degrees, P2l/c) occurs at a characteristic dose (10−4C/cm2) which is five orders of magnitude smaller than the critical end point dose (20 C/cm2). Previously we discussed the progress of this phase transition primarily as observed down the [001] zone (the chain axis direction). Here we report on the associated changes of the dark field (DF) images and selected area electron diffraction (SAED) patterns of the crystals as observed from the side (i.e., in the [hk0] zones).High resolution electron micrographs (HREM), DF images, and SAED patterns were obtained on a JEOL 4000 EX HREM operating at 400 kV.

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14

Zheng, Jun, and Wei Zhou. "Low Temperature Synthesis of Nanoscale Magnesium Hydroxide under Normal Pressure." Advanced Materials Research 779-780 (September 2013): 247–50. http://dx.doi.org/10.4028/www.scientific.net/amr.779-780.247.

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In the present paper, nano-scale magnesium hydroxide has been prepared at low temperature via a wet chemical process using MgCl2· 6H2O (or Mg(NO3)2) and NaOH as the starting reagents under normal pressure. The fresh synthesized magnesium hydroxide nanocrystals were characterized by X-ray diffraction (XRD), selected area electronic diffraction (SAED) and transmission electron microscopy (TEM) measurements. Patterns of XRD and SAED exhibited that the products were high-quality hexagonal crystal system nanocrystals. Though the TEM pictures, large quantities of lamellar-like and needle-like magnesium hydroxide nanocrystals could be observed without obvious aggregation. Using the present method, high yield magnesium hydroxide nanoparticles would be produced without expensive equipments like the high temperature and high-pressure reactor.

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15

Walck, Scott D. "Recipes for Consistent Selected Area Electron Diffraction Results: Part 2: Recording the SAED Pattern." Microscopy Today 28, no. 3 (May 2020): 54–59. http://dx.doi.org/10.1017/s1551929520000887.

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16

Wang, Hai Bo, Li Ma, and Wei Cai. "Effect of Annealing Conditions on Microstructure Evolution of NiMnFeGa Shape Memory Thin Film." Advanced Materials Research 150-151 (October 2010): 1745–49. http://dx.doi.org/10.4028/www.scientific.net/amr.150-151.1745.

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The microstructure evolution of sputtered polycrystalline Ni54.75Mn13.25Fe7Ga25 ferromagnetic shape memory thin film annealed under different conditions is studied. Microstructure of different annealed films was studied using Transmission Electron Microscope (TEM) and corresponding selected area electron diffraction (SAED) patterns. The result shows that in the microstructure of as-deposited Ni54.75Mn13.25Fe7Ga25 free-standing film, after annealed at 1073 K for different time, the crystalline grain grows up with the increase of the annealing time. By analysis of the SAED patterns, the structure of the thin films change from face-centered cubic austenite to orthorhombic structure martensite compared between the film annealed at 1073 K for 10 mins, 1hr, 4 hrs, and 24 hrs respectively. It indicated that the heat treatment is an effective method of crystallizing behavior for the thin film.

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17

Hsu, Hung Pin, Ying Sheng Huang, Chien Nan Yeh, Yi Min Chen, Dah Shyang Tsai, and Kwong Kau Tiong. "Growth and Characterization of Well-Aligned RuO₂/R-TiO₂ Heteronanostructures on Sapphire (100) Substrates by Reactive Magnetron Sputtering." Solid State Phenomena 170 (April 2011): 78–82. http://dx.doi.org/10.4028/www.scientific.net/ssp.170.78.

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We report the growth of well-aligned RuO2/R-TiO2 heteronanostructures on sapphire (100) substrates by reactive magnetron sputtering using Ti and Ru metal targets under different conditions. The surface morphology and structural properties of the as-deposited heteronanostructures were characterized using field-emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), transmission electron microscopy (TEM) and selected-area electron diffractometry (SAED). The FESEM micrographs and XRD patterns indicated the growth of vertically aligned RuO2(001) nanotubes and twinned V-shaped RuO2(101) nanowedges (NWs) on top of R-TiO2 nanorods under different sputtering pressures. TEM and SAED characterizations of the V-shaped RuO2 NWs showed that the NWs are crystalline RuO2 with twin planes of (101) and twin direction of [ 01] at the V-junction.

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18

Seo, Pooreun, Kazuhiro Yasuda, Syo Matsumura, Norito Ishikawa, Gaëlle Gutierrez, and Jean-Marc Costantini. "Microstructure evolution in 200-MeV Xe ion irradiated CeO₂ doped with Gd₂O₃." Journal of Applied Physics 132, no. 23 (December 21, 2022): 235902. http://dx.doi.org/10.1063/5.0121951.

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The microstructure of virgin and heavy ion-irradiated Ce1–xGdxO2–x/2 with a wide range of Gd dopant concentrations (0 ≤ xGd ≤ 0.5) was evaluated by x-ray diffraction (XRD), micro-Raman spectroscopy, and transmission electron microscopy (TEM) for selected area electron diffraction (SAED) analysis and plane-view bright-field (BF) imaging of ion tracks. The Ce1–xGdxO2–x/2 samples were irradiated with 200-MeV Xe14+ ions up to fluences from 3 × 1011 to 1 × 1013 cm−2 at ambient temperature. XRD patterns of the virgin Ce1–xGdxO2–x/2 samples showed saturation of lattice parameter and relaxation of microstrain in Ce1–xGdxO2–x/2 which are attributed to the increasing Gd concentration. Moreover, micro-Raman spectroscopy and SAED patterns revealed the bixbyite (C-type) structure formation and oxygen vacancy ordering for xGd > 0.2 that is induced by dispersed C-type domains in the fluorite-structured (F-type) matrix. In the irradiated samples, asymmetric XRD peaks induced by lattice distortion were observed together with ion tracks in BF-TEM images. The radiation damage was recovered with the increase of Gd concentration. There is a rapid reduction of radiation damage cross section for xGd > 0.2 with a reduction of the C-type structure reflections in XRD and SAED patterns.

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19

Bhatt, Sandip V., M. P. Deshpande, Bindiya H. Soni, Nitya Garg, and Sunil H. Chaki. "Chemical Bath Deposition of Lead Sulphide (PbS) Thin Film and their Characterization." Solid State Phenomena 209 (November 2013): 111–15. http://dx.doi.org/10.4028/www.scientific.net/ssp.209.111.

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Thin film deposition of PbS is conveniently carried out by chemical reactions of lead acetate with thiourea at room temperature. Energy dispersive analysis of X-ray (EDAX), X-ray diffraction (XRD), selected area electron diffraction patterns (SAED), UV-Vis-NIR spectrophotometer, Scanning Electron Microscopy (SEM), Atomic force microscopy (AFM), Photoluminescence (PL) and Raman spectroscopy techniques are used for characterizing thin films. EDAX spectra shows that no impurity is present and XRD pattern indicates face centered cubic structure of PbS thin films. The average crystallite size obtained using XRD is about 15nm calculated using Scherrer’s formula and that determined from Hall-Williamson plot was found to be 18nm. SAED patterns indicate that the deposited PbS thin films are polycrystalline in nature. Blue shift due to quantum confinement was seen from the UV-Vis-NIR absorption spectra of thin film in comparison with bulk PbS. The Photoluminescence spectra obtained for thin film with different excitation sources shows sharp emission peaks at 395nm and its intensity of photoluminescence increases with increasing the excitation wavelength. Raman spectroscopy of deposited thin film was used to study the optical phonon modes at an excitation wavelength of 488nm using (Ar+) laser beam.

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20

Yang, Wei, Chun Xiang Cui, Qiao Zhi Liu, and Ji Bing Sun. "Fabrication and Characterization of Integrated Ultrahigh-Density Pt Nanowire Arrays within the AAO Template." Materials Science Forum 789 (April 2014): 1–5. http://dx.doi.org/10.4028/www.scientific.net/msf.789.1.

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The parallel Pt nanowires with highly ordered array and the length more than a dozen micrometers were prepared by the direct current electro-deposition in porous anodic aluminum oxide (AAO) templates. The deposition was performed in a aqueous solution of the Pt (NO2)2(NH3)2 composite electrolyte. The images and structure of Pt nanowire arrays were obtained by field emission scanning electron microscope (FESEM) and transmission electron microscope (TEM), respectively. Selected area electron diffraction (SAED) are employed to study the crystalline morphology of Pt nanowire arrays. The relationship between the nanowires length and electro-deposition time was discussed. Their growth speed is about 0.5μm/h. The TEM micrographs show that these nanowires have uniform diameter of approximate 55nm. SAED pattern reveals that the Pt nanowire has a polycrystalline structure.

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21

Liu, Hao, Li Fan, Qichen Wei, Haizeng Song, Hongliang Zhu, Mengdi Hu, and Shancheng Yan. "Preparation of single crystal triangular selenium nanostructures and photoelectric properties." Materials Express 12, no. 4 (April 1, 2022): 609–15. http://dx.doi.org/10.1166/mex.2022.2189.

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Anisotropic growth of selenium leads to formation of one-dimensional structure of selenium, and reaction conditions mostly determine the morphology of products. In this study, one-dimensional selenium materials were prepared directly from selenium powder by microwave-assisted method. Selenium nanotubes and selenium nanorods were synthesized by adjusting the ratio of ethylene glycol to water. The as-prepared products were characterized by Transmission Electron Microscope (TEM), Selected area electron diffraction (SAED), X-ray diffraction (XRD), Raman spectroscopy, photoluminescence spectroscopy and UV-Vis absorption spectroscopy, and their electrical properties were also tested. Results from High Resolution Transmission Electron Microscope (HRTEM), SAED and XRD patterns showed that the prepared selenium nanotubes had good single crystal microstructure, and its possible growth direction of t-se nanotubes was 001. The selenium nanotubes had strong light response compared with dark condition under 650 nm laser irradiation. We hope that the selenium nanotubes will have a better development prospect in the direction of semiconductor devices.

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22

Kumar, Challa S. S. R., Mher Aghasyan, Hartwig Modrow, Josef Hormes, and Rolland Tittsworth. "Gold Nanoparticles on Polymeric Micro Beads: A One-Pot Synthesis and Characterization by X-Ray Absorption Near Edge Structure (XANES) Spectroscopy." Journal of Metastable and Nanocrystalline Materials 23 (January 2005): 343–46. http://dx.doi.org/10.4028/www.scientific.net/jmnm.23.343.

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Cetyl trimethyl ammonium bromide (CTAB) stabilized gold(III) salt in chloroform was reduced using NaBH4 in the presence of commercially available methanethiol-polyphoResinTM to obtain polystyrene micro beads with gold nanoparticles on their surface. X-ray Absorption Near Edge Spectra (XANES) of Au and S revealed S-Au bonding state. TEM studies coupled with Selected Area Electron Diffraction(SAED) patterns revealed the morphology of the Au nanoparticles on the surface of the micro beads.

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23

Lábár, J. L., M. Adamik, B. P. Barna, Zs Czigány, Zs Fogarassy, Z. E. Horváth, O. Geszti, et al. "Electron Diffraction Based Analysis of Phase Fractions and Texture in Nanocrystalline Thin Films, Part III: Application Examples." Microscopy and Microanalysis 18, no. 2 (March 21, 2012): 406–20. http://dx.doi.org/10.1017/s1431927611012803.

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AbstractIn this series of articles, a method is presented that performs (semi)quantitative phase analysis for nanocrystalline transmission electron microscope samples from selected area electron diffraction (SAED) patterns. Volume fractions and degree of fiber texture are determined for the nanocrystalline components. The effect of the amorphous component is minimized by empirical background interpolation. First, the two-dimensional SAED pattern is converted into a one-dimensional distribution similar to X-ray diffraction. Volume fractions of the nanocrystalline components are determined by fitting the spectral components, calculated for the previously identified phases with a priori known structures. These Markers are calculated not only for kinematic conditions, but the Blackwell correction is also applied to take into account dynamic effects for medium thicknesses. Peak shapes and experimental parameters (camera length, etc.) are refined during the fitting iterations. Parameter space is explored with the help of the Downhill-SIMPLEX. The method is implemented in a computer program that runs under the Windows operating system. Part I presented the principles, while part II elaborated current implementation. The present part III demonstrates the usage and efficiency of the computer program by numerous examples. The suggested experimental protocol should be of benefit in experiments aimed at phase analysis using electron diffraction methods.

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24

Rudolph, Martin, Mykhaylo Motylenko та David Rafaja. "Structure model of γ-Al2O3 based on planar defects". IUCrJ 6, № 1 (1 січня 2019): 116–27. http://dx.doi.org/10.1107/s2052252518015786.

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The defect structure of γ-Al2O3 derived from boehmite was investigated using a combination of selected-area electron diffraction (SAED) and powder X-ray diffraction (XRD). Both methods confirmed a strong dependence of the diffraction line broadening on the diffraction indices known from literature. The analysis of the SAED patterns revealed that the dominant structure defects in the spinel-type γ-Al2O3 are antiphase boundaries located on the lattice planes (00l), which produce the sublattice shifts {{1}\over{4}}\langle 10{\overline 1}\rangle. Quantitative information about the defect structure of γ-Al2O3 was obtained from the powder XRD patterns. This includes mainly the size of γ-Al2O3 crystallites and the density of planar defects. The correlation between the density of the planar defects and the presence of structural vacancies, which maintain the stoichiometry of the spinel-type γ-Al2O3, is discussed. A computer routine running on a fast graphical processing unit was written for simulation of the XRD patterns. This routine calculates the atomic positions for a given kind and density of planar defect, and simulates the diffracted intensities with the aid of the Debye scattering equation.

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25

Yan, De, Yan Hong Li, Ying Liu, Ren Fu Zhuo, Zhi Guo Wu, and Jun Wang. "Growth Mechanism and Morphology Control of Porous Hexagonal Plates of Hydrohausmannite Prepared by Hydrothermal Method." Applied Mechanics and Materials 513-517 (February 2014): 277–80. http://dx.doi.org/10.4028/www.scientific.net/amm.513-517.277.

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Porous hexagonal plates of hydrohausmannite were prepared by a simple hydrothermal method. Morphology control of the product was easily achieved by adjusting the experimental parameters. The selected area electron diffraction (SAED) patterns show obvious evidence that these hexagonal plates were formed by oriented aggregation-based growth of subunits, which is discussed in details. Intriguing well-shaped hexagonal pores were obtained when the hexagonal plates were exposed to high intensity electron beam irradiation. These hexagonal plates of manganese oxide may have wide applications as components and/or interconnect in nanodevices and/or as nanotools.

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26

Tsuji, Masaki, Fernando A. Novillo L, Masahiro Fujita, Syozo Murakami, and Shinzo Kohjiya. "Morphology of melt-crystallized poly(ethylene 2,6-naphthalate) thin films studied by transmission electron microscopy." Journal of Materials Research 14, no. 1 (January 1999): 251–58. http://dx.doi.org/10.1557/jmr.1999.0037.

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Thin films of poly(ethylene 2,6-naphthalate) (PEN) were isothermally crystallized at 190 °C after being melted at 300 °C. Morphological observation by transmission electron microscopy (TEM) showed the spherulitic texture in the films. Selected-area electron diffraction (SAED) indicated that the crystals in the films are the a form, as expected from our thermal condition for crystallization. The SAED pattern from the untilted specimen was characterized by the fairly intense reflection ring accompanied by other weak rings, and this intense ring was indexed as 010. A series of SAED patterns, which were obtained from the same specimen area tilted at various angles in the TEM column, suggested that the crystallites are oriented with their (001) planes being preferentially parallel to the film surface. Subsequently, a set of the dark-field images of the two-dimensional spherulite taken by using two different parts of the 010 reflection ring revealed that most of the crystallites in such a spherulite are oriented with their (010) planes being parallel in its radial direction. In addition, the spherulites in small pieces (0.05–0.08 mm thick) of PEN, which had been crystallized under the same thermal condition as above, were determined to be negatively birefringent by polarizing light microscopy.

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27

Zeng, Yang Zheng, Kai Ming Wu, Feng Hu, and Hua Zheng. "Effect of Partitioning of Quenching-Partitioning-Tempering Process on Microstructures and Hardness in High Carbon Steels." Advanced Materials Research 538-541 (June 2012): 1053–56. http://dx.doi.org/10.4028/www.scientific.net/amr.538-541.1053.

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The effect of partitioning process of quenching-partitioning-tempering (Q-P-T) process on hardness and microstructure were investigated. The 1-step Q-P-T and 2-step Q-P-T heat treatment were designed and carried out. The microstructure and carbides were analyzed by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and selected area electron diffraction (SAED) patterns. Results showed that compared with 1-step Q-P-T heat treatment, more amount of retained austenite was obtained by 2-step Q-P-T heat treatment, however, the carbides were bigger in size and the hardness was lower.

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28

Al-Agel, F. A., and Waleed E. Mahmoud. "Synthesis and characterization of highly stoichiometric AgInSe2thin filmsviaa sol–gel spin-coating technique." Journal of Applied Crystallography 45, no. 5 (September 1, 2012): 921–25. http://dx.doi.org/10.1107/s002188981203511x.

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Highly stoichiometric AgInSe2thin films have been prepared on a p-type Si(111) substrate by a sol–gel spin-coating technique. These films were annealed at different temperatures. The as-prepared and annealed films were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED) and X-ray photoelectron spectroscopy (XPS). The XRD spectra showed that the crystal structure of the AgInSe2film was that of cubic fluorite chalcopyrite with lattice constantsa= 6.102 Å andc= 11.69 Å. The SEM images depicted the surface morphology as smooth and the spherical particles as uniformly distributed. The average particle size was increased as the annealing temperature increased. Using HRTEM images and SAED patterns for the as-synthesized and annealed thin films, the AgInSe2film was indexed to a pure polycrystalline chalcopyrite AgInSe2structure with a lattice spacing of around 0.3 nm. XPS spectra showed that the as-deposited AgInSe2film was Ag rich, while the AgInSe2films annealed at 523 and 623 K were In rich.

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29

Raanes, M., and J. Hjelen. "Analysis of Asbestos Fibres in The Scanning Electron Microscope (SEM) by The Use of Electron Backscattering Diffraction (Ebsd)." Microscopy and Microanalysis 3, S2 (August 1997): 767–68. http://dx.doi.org/10.1017/s1431927600010722.

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Asbestos is a common name of a number of fibrous mineral silicates which differ in chemical composition. The asbestos fibres are classified into two groups: serpentine (chrysotile) and amphiboles (anthophyllite, amosite, actinolite, tremolite, crocidolite).Inhalation of asbestos dust fibres involves a health risk. It is therefore of great importance to develop quick and reliable methods to check for the presence of asbestos fibres in suspected materials. Some common analysis methods for asbestos detection are: optical microscopy scanning or transmission electron microscopies (SEM ,TEM) often combined with energy dispersive X-ray analysis (EDX) and selected area electron diffraction (SAED) in the TEM where the crystal structure is determined.The EBSD technique in the SEM has in this work been applied to achieve electron backscattering patterns (EBSP) from four types of asbestos fibres. The pattern quality has been studied as a function of specimen preparation and SEM settings.

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30

Zhang, Junhao, Yuhui Wu, Jia Zhu, Shaoxing Huang, Dongjing Zhang, and Qinghuan Yin. "Synthesis and optical properties of self-assembled flower-like CdS architectures by mixed solvothermal process." Open Chemistry 8, no. 5 (October 1, 2010): 1027–33. http://dx.doi.org/10.2478/s11532-010-0075-2.

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AbstractSelf-assembled CdS architectures with flower-like structures have been synthesized by a mixed solvothermal method using ethylene glycol and oleic acid as the mixed solvent at 160°C for 12 h. The results of X-ray diffraction (XRD) patterns, field-emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) images indicate that the product exists as the hexagonal wurtzite phase and conatins of larger numbers of flower-like CdS architectures with diameters of 1.8–3 μm. The selected-area electron diffraction (SAED) pattern and the high resolution transmission electron microscope (HRTEM) image reveal that the grain has better crystallinity. The optical properties of flower-like CdS architectures were also investigated by ultraviolet-visable (UV-vis) and photoluminescence spectroscopy at room temperature. A strong peak at 490 nm is shown in the UV-vis absorption, while an emission at 486 nm and another strong emission at 712 nm are shown in the PL spectrum.

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31

Kumar, Brajesh, Kumari Smita, Luis Cumbal, Alexis Debut, and Ravinandan Nath Pathak. "Sonochemical Synthesis of Silver Nanoparticles Using Starch: A Comparison." Bioinorganic Chemistry and Applications 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/784268.

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Анотація:

A novel approach was applied to synthesize silver nanoparticles using starch under sonication. Colloidal silver nanoparticles solution exhibited an increase of absorption from 420 to 440 nm with increase starch quantity. Transmission electron microscopy followed by selected area electron diffraction pattern analysis indicated the formation of spherical, polydispersed, amorphous, silver nanoparticles of diameter ranging from 23 to 97 nm with mean particle size of 45.6 nm. Selected area electron diffraction (SAED) confirmed partial crystalline and amorphous nature of silver nanoparticles. Silver nanoparticles synthesized in this manner can be used for synthesis of 2-aryl substituted benzimidazoles which have numerous biomedical applications. The optimized reaction conditions include 10 ml of 1 mM AgNO3, 25 mg starch, 11 pH range, and sonication for 20 min at room temperature.

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32

Nishi, T., Sakae Tanemura, Lei Miao, Masaki Tanemura, and K. Suzuki. "Fabrication of TiO₂-Aerogel with NiB Nano-Clusters and Its Structural Characterization and Catalysis Evaluation." Advanced Materials Research 11-12 (February 2006): 7–10. http://dx.doi.org/10.4028/www.scientific.net/amr.11-12.7.

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We have prepared titania aerogel (=AG) embedded by NiB nano-clusters by sol-gel method, immersion of the prepared wet gel into the NiB dispersed solution, and the subsequent super critical drying (=SCD). The AG was characterized by X-ray diffraction (XRD), a transmission electron microscopy (TEM), and a fourier transform infrared spectrophotometer (FT-IR). XRD and selected area electron diffraction (SAED) patterns assured the formation of TiO2 anatase phase. TEM observation reveled the composition of TiO2 crystallites with about 4 nm in size. Catalyst performance for the ground sample was confirmed by chemical reaction of oxidation of benzene at low temperature, and the difference in catalyst performance between TiO2 AGs with and without the embedded NiB nano-clusters has been examined.

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33

Tempesta, G., G. Agrosì, G. C. Capitani, and Eugenio Scandale. "XRDT and TEM Study of Defects and Polytypism in Natural Moissanite and Synthetic SiC Crystals." Advances in Science and Technology 48 (October 2006): 61–66. http://dx.doi.org/10.4028/www.scientific.net/ast.48.61.

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Structural defects and degree of order of natural and synthetic moissanite have been investigated by XRD Topography and TEM. XRDT analyses of synthetic 6H-SiC wafers allowed to study extended defects and to identify and localize coalescence of polytypes. The observed linear defects are microchannels and dislocations. Axial screw dislocations, either parallel or slightly inclined to the c-axis, suggest that the growth mechanism for the bulk crystals was mainly by spiral growth. Moreover, the study of line orientations of the dislocations allow to reconstruct the growth sector evolution of the sample. Therefore, the convex shape of the growing surface is attained by the development of growth sectors (10l) neighbouring growth sector (001). The coalescence of a thin lamella of a different polytype has been also localized and investigated. The contrast analysis and the diffraction pattern of the lamella are consistent with a 15R-SiC crystal. Such coalescence indicates local variations of growth conditions. TEM images and selected area electron diffractions (SAEDs) strongly differentiate natural from synthetic samples. SAED patterns with [010] incidence of natural crystals are consistent with the 6H polytype and do not show streaks along the [001] stacking direction. Synthetic samples are comparatively much more disordered. Conventional images show high density of (001) faults, not observed in natural samples. Consistently, SAED patterns of the [100] zone are streaked along c*. High resolution (HR) imaging shows that synthetic samples mainly consist of (001) stacking sequence described as (32)3. Locally mixed stacking sequence described by notation 23(3233)5, probably referred to a long period polytype, are present.

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34

Rozhdestvenskaya, I. V., T. Kogure, E. Abe, and V. A. Drits. "A structural model for charoite." Mineralogical Magazine 73, no. 5 (October 2009): 883–90. http://dx.doi.org/10.1180/minmag.2009.073.2.883.

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AbstractThe crystal structure of charoite was investigated mainly by using selected-area electron diffraction (SAED), X-ray diffraction (XRD) and high-resolution electron microscopy (HREM). SAED and XRD patterns indicate that the structure has a monoclinic cell: a = 32.296, b = 19.651, c = 7.16 Å, β = 96.3° and V = 4517 Å3. The space group inferred from systematic absences and HREM images is P21/m. A model of the charoite structure is proposed that is based on the features of related Ca-alkaline silicate structures and HREM images. The structure of charoite consists of three different silicon-oxygen radicals (polymerized SiO4 tetrahedra) which are located between Ca polyhedra. Two of these radicals form continuous tubular structures comprising pectolite-like tetrahedral chains. Calcium polyhedra are joined to form blocks, each of which consists of four columns sharing edges and apices. Potassium and H2O molecules are probably located inside the tubular silicate radicals. From these results, a general formula is derived: K6-7(Ca,Na)18[(Si6O17)(Si12O30)(Si18O45)](OH,F)2.nH2O with two formula units in the unit cell (Z = 2).

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35

Fang, Fei, and Xiaowen Zhang. "X-ray diffraction and high-resolution transmission electron microscopy study on A-site ordering of lanthanum-modified lead zirconate titanate relaxor." Journal of Materials Research 10, no. 7 (July 1995): 1582–84. http://dx.doi.org/10.1557/jmr.1995.1582.

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The ordering behavior of La-modified lead zirconate titanate relaxor (PLZT 9/65/35) was investigated by use of an x-ray diffractometer (XRD) and high-resolution transmission electron microscopy (HRTEM). It was shown that a {h + 1/2, k + 1/2, 0}-type superlattice exists both in the x-ray diffraction pattern and selected area electron diffraction (SAED) image. High-resolution electron micrographs further demonstrated the existence of the superlattice and exposed the ordered and disordered regions in the lattice level. A model referring to an A-site body-centered pseudo-cubic superstructure was proposed.

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36

Cao, Chuan Bao, Ruitao Lv, and He Sun Zhu. "Preparation of Single-Crystal BiOCl Nanorods via Surfactant Soft-Template Inducing Growth." Journal of Metastable and Nanocrystalline Materials 23 (January 2005): 79–82. http://dx.doi.org/10.4028/www.scientific.net/jmnm.23.79.

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Nanorods of a compound semiconductor, BiOCl, have been prepared from BiCl3 solutions containing a nonionic surfactant, t-octyl-(OCH2CH2)xOH, x=9, 10 (Triton X-100). Powder X-ray diffraction (XRD) pattern indicated that the product was pure tetragonal phase bismoclite (BiOCl). The product was also characterized by the techniques of scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS) and transmission electron microscope (TEM). The as-obtained BiOCl nanorods possess mean diameters less than 40nm and lengths ranging in 160-400nm. Selected area electron diffraction (SAED) pattern showed the single-crystal nature of as-prepared BiOCl nanorods. The growth mechanism of BiOCl nanorods has also been proposed.

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37

Le, Van Thuan, Ngoc Nhu Quynh Ngu, Tan Phat Chau, Thi Dung Nguyen, Van Toan Nguyen, Thi Lan Huong Nguyen, Xuan Thang Cao, and Van-Dat Doan. "Silver and Gold Nanoparticles from Limnophila rugosa Leaves: Biosynthesis, Characterization, and Catalytic Activity in Reduction of Nitrophenols." Journal of Nanomaterials 2021 (May 20, 2021): 1–11. http://dx.doi.org/10.1155/2021/5571663.

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This study describes a simple green method for the synthesis of Limnophila rugosa leaf-extract-capped silver and gold nanoparticles without using any expensive toxic reductant or stabilizer. The noble metal nanoparticles were characterized by Fourier transform infrared (FTIR) microscopy, powder X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray analysis (EDX), high-resolution transmission electron microscopy (HR-TEM), selected area electron diffraction (SAED), and dynamic light scattering (DLS) method. It has been found that the biosynthesized silver and gold nanoparticles are nearly spherical in shape with a mean particle size distribution of 87.5 nm and 122.8 nm, respectively. XRD and SAED patterns confirmed the crystalline nanostructure of the metal nanoparticles. FTIR spectra revealed the functional groups of biomolecules presented in the extract possibly responsible for reducing metallic ions and stabilizing formed nanoparticles. The biosynthesized metal nanoparticles have potential application in catalysis. Compared to previous reports, Limnophila rugosa leaf-extract-capped silver and gold nanoparticles exhibited a good catalytic activity in the reduction of several derivatives of nitrophenols including 1,4-dinitrobenzene, 2-nitrophenol, 3-nitrophenol, and 4-nitrophenol.

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38

King, Graham, Susana Garcia-Martin, and Patrick M. Woodward. "Octahedral tilt twinning and compositional modulation in NaLaMgWO6." Acta Crystallographica Section B Structural Science 65, no. 6 (October 27, 2009): 676–83. http://dx.doi.org/10.1107/s0108768109032728.

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Анотація:

A combination of selected-area electron diffraction (SAED), neutron powder diffraction (NPD) and high-resolution transmission electron microscopy (HRTEM) reveals a complex superstructure in the ordered perovskite NaLaMgWO6. Through indexing of SAED patterns the unit-cell dimensions are found to be 46.8 × 7.8 × 7.9 Å, which corresponds to a 12a p × 2a p × 2a p superstructure of the simple Pm\overline 3 m perovskite unit cell. HRTEM images reveal the formation of an unmistakable stripe contrast that repeats with the same periodicity. Doubling of the b and c axes is brought about by a combination of layered ordering of Na and La, rock-salt ordering of Mg and W, and octahedral tilting. The a axis repeat distance results from a one-dimensional twinning of the octahedral tilts in combination with a compositional modulation. Modeling of the NPD pattern shows that the underlying tilt system is a − a − c 0 with tilt angles of ∼ 8° about the a and b axes. The octahedral tilt-twin boundaries run perpendicular to the a axis and are separated by 6a p. Simulated HRTEM images show that octahedral tilt twinning alone cannot explain the stripes seen in the HRTEM images, rather a compositional modulation involving the A-site cations is necessary to explain the experimental images.

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39

Zheng, Xinliang, Juan Feng, Jiarui Zhang, Hongna Xing, Jiming Zheng, Mingzi Wang, Yan Zong, Jintao Bai, and Xinghua Li. "Anomalous Ferromagnetism and Electron Microscopy Characterization of High-Quality Neodymium Oxychlorides Nanocrystals." Nano 11, no. 03 (March 2016): 1650034. http://dx.doi.org/10.1142/s179329201650034x.

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Анотація:

High-quality neodymium oxychlorides nanocrystals with cubic shape were synthesized by a nonhydrolytic thermolysis route. The morphology and crystal structure of the neodymium oxychlorides nanocubes were characterized by transmission electron microscopy at the nanoscale. Transmission electron microscope (TEM) image shows that the neodymium oxychlorides nanocrystals are nearly monodispersed with cube-like shape. X-ray diffraction (XRD) and selected area electron diffraction (SAED) patterns of numerous neodymium oxychlorides nanocubes suggest a pure crystal phase with tetragonal PbFCl matlockite structure. HRTEM image of individual neodymium oxychlorides nanocubes indicate that each nanocubes have a single-crystalline nature with high quality. Unlike the anti-ferromagnetism of the bulk, the neodymium oxychlorides nanocubes show clearly anomalous ferromagnetic characteristic at room temperature. This finding provides a new platform for the exploration of diluted magnetic semiconductors, rare earth-based nanomaterials and so on.

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40

Schierholz, Roland, and Hartmut Fuess. "Ferroelectric domains in PZT ceramics at the morphotropic phase boundary. Can the splitting of reflections in SAED patterns be used for the distinction of different pseudo-cubic phases?" Journal of Applied Crystallography 45, no. 4 (June 20, 2012): 766–77. http://dx.doi.org/10.1107/s0021889812022583.

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Tetragonal, rhombohedral and monoclinic ferroelectric domains can all occur in morphotropic PbZr1−xTixO3(PZT) ceramics. In this article, the influence of these domains on the splitting of reflections in selected area electron diffraction (SAED) patterns along the main pseudo-cubic zone axes is reported. The orientation of the domain wall in a transmission electron microscopy image with respect to the splitting of reflections in the diffraction pattern has to be considered for the interpretation. The distinction of tetragonal and rhombohedral splitting is achieved for a pronounced splitting except for 〈111〉 with the domain wall edge on. As the monoclinic structure contains tetragonal as well as rhombohedral distortions, the distinction of monoclinic symmetry from tetragonal and rhombohedral based only on the splitting of reflections is not possible. Conceivable models of configurations of monoclinic subdomains inside the existing tetragonal or rhombohedral microdomains are derived from group–subgroup relations. Some experimental observations are given, which can only be explained by these models.

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41

D'Angelo, Anita M., and Nathan A. S. Webster. "Evidence of anatase intergrowths formed during slow cooling of reduced ilmenite." Journal of Applied Crystallography 51, no. 1 (February 1, 2018): 185–92. http://dx.doi.org/10.1107/s1600576718000493.

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Controlling the parameters during synthetic rutile production is essential to minimize production costs and ensure final product quality. Powder X-ray diffraction (PXRD) is typically used within the industry to guide process control. This work investigated the source of unusual features observed in the PXRD pattern of a slow-cooled reduced ilmenite (RI), which were not observed for a rapid-cooled RI. For the slow-cooled RI, the 002 peak ofM3O5(anosovite) had disappeared and the intensity of the \bar 203, 203, 204 and 402 peaks had decreased significantly compared to the pattern for the rapid-cooled RI. Using transmission electron microscopy, selected area electron diffraction (SAED) and pair distribution function (PDF) analysis, the authors attribute these features toM3O5–anatase intergrowth formation, which causes a loss in long-range order along theM3O5caxis. Strong diffuse streaking in the SAED patterns was also evident and supported the presence of disordered intergrowths from the oxidation ofM3O5. PDF analysis showed a significant improvement in the fit to the data for the slow-cooled RI, primarily in the <17 Å region, when anatase was added to the PDF model. The results presented here highlight the importance of the reduction and cooling stages during the formation of these industrially relevant RI minerals, which may be used to direct the production process and final TiO2product quality.

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42

Hower, James, Dali Qian, Nicolas Briot, Eduardo Santillan-Jimenez, Madison Hood, Ross Taggart, and Heileen Hsu-Kim. "Nano-Scale Rare Earth Distribution in Fly Ash Derived from the Combustion of the Fire Clay Coal, Kentucky." Minerals 9, no. 4 (March 30, 2019): 206. http://dx.doi.org/10.3390/min9040206.

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Анотація:

Fly ash from the combustion of eastern Kentucky Fire Clay coal in a southeastern United States pulverized-coal power plant was studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and selected area electron diffraction (SAED). TEM combined with elemental analysis via energy dispersive X-ray spectroscopy (EDS) showed that rare earth elements (REE; specifically, La, Ce, Nd, Pr, and Sm) were distributed within glassy particles. In certain cases, the REE were accompanied by phosphorous, suggesting a monazite or similar mineral form. However, the electron diffraction patterns of apparent phosphate minerals were not definitive, and P-lean regions of the glass consisted of amorphous phases. Therefore, the distribution of the REE in the fly ash seemed to be in the form of TEM-visible nano-scale crystalline minerals, with additional distributions corresponding to overlapping ultra-fine minerals and even true atomic dispersion within the fly ash glass.

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43

Zhao, Shi Chao, Ke Xie, Chang Jiang Song, and Qi Jie Zhai. "Preparation of TEM Specimens from Gas-Atomized Fe-6.5wt.%Si Powders with Several Micrometers Using Focused Ion Beam." Advanced Materials Research 706-708 (June 2013): 224–29. http://dx.doi.org/10.4028/www.scientific.net/amr.706-708.224.

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Анотація:

Transmission electron microscopy (TEM) can be utilized to identify some specific microstructures of metals and alloys. However, it is very difficult to precisely prepare a TEM specimen from the powder particles with several micrometers. There are more or less drawbacks in conventional preparation method. This paper describes a novel method to prepare specific specimens from the powder particles with several micrometers for TEM study. A TEM specimen approximately 5μm diameter was successfully prepared to electron transparency, which extracted from a 5μm diameter powder particle. The selected-area electron diffraction pattern (SAED) analysis was carried out.

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44

Chaithanatkun, Natpasit, Korakot Onlaor, Thutiyaporn Thiwawong, and Benchapol Tunhoo. "Modification of Structural and Vibrational Properties of ZnO Nanoparticles Prepared by Simple Chemical Precipitation Method." Key Engineering Materials 675-676 (January 2016): 138–41. http://dx.doi.org/10.4028/www.scientific.net/kem.675-676.138.

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In this work, zinc oxide (ZnO) nanoparticles were synthesized by simple chemical precipitation method in the present of zinc nitrate as zinc precursor and sodium hydroxide as hydroxide precursor. The vitamin C was used as modifier media to modify the structural properties of ZnO nanoparticles. The microstructures of ZnO nanoparticles were characterized by field emission scanning electron microscope (FE-SEM) and transmission electron microscope (TEM). Selected area electron diffraction (SAED) patterns showed that polycrystalline hexagonal phase of ZnO. The defects and impurity contents in nanoparticles were investigated by Fourier transform infrared (FT-IR) spectroscopy. The results show few carboxylate and hydroxyl impurities for larger particles when addition modifier increases. Surface areas of nanoparticles were measured by Brunauer Emmett Teller (BET) method. In addition, the results exhibited the dramatically change in structural properties of ZnO nanoparticles due to the effect of vitamin C.

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45

LI, XUYANG, NAOKI KISHI, and TETSUO SOGA. "SYNTHESIS OF ZINC OXIDE THIN FILM WITH THREAD-LIKE NANOWIRES ON FLUORINE DOPED TIN OXIDE GLASS SUBSTRATES." Modern Physics Letters B 27, no. 32 (December 12, 2013): 1350237. http://dx.doi.org/10.1142/s0217984913502370.

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In this paper, ZnO thin film has been synthesized on fluorine doped tin oxide (FTO) glass substrate by annealing the Zn film in air flow. The SEM image shows that the high density and thread-like ZnO nanowires could grow on the thin film. XRD pattern shows that ZnO was the only compound. The high-resolution transmission electron microscopy (HRTEM) results of individual ZnO nanowires show that the nanowires grown on the ZnO thin film are single-crystalline, and the selected area electron diffraction pattern (SAED) shows that the nanowires grow along the (001) direction.

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46

Kenik, Edward A. "Spatial Resolution of Electron Backscatter Diffraction in a FEG-SEM." Proceedings, annual meeting, Electron Microscopy Society of America 54 (August 11, 1996): 348–49. http://dx.doi.org/10.1017/s0424820100164209.

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Анотація:

Crystallographic information can be determined for bulk specimens in a SEM by utilizing electron backscatter diffraction (EBSD), which is also referred to as backscatter electron Kikuchi diffraction. This technique provides similar information to that provided by selected area electron channeling (SAEC). However, the spatial resolutions of the two techniques are limited by different processes. In SAEC patterns, the spatial resolution is limited to ˜2 μm by the motion of the beam on the specimen, which results from the angular rocking of the beam and the aberration of the probe forming lens. Therefore, smaller incident probe sizes provide no improvement in spatial resolution of SAEC patterns. In contrast, the spatial resolution for EBSD, which uses a stationary beam and an area detector, is determined by 1) the incident probe size and 2) the size of the interaction volume from which significant backscattered electrons are produced in the direction of the EBSD detector. The second factor is influenced by the accelerating voltage, the specimen tilt, and the relative orientation of scattering direction and the specimen tilt axis.

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47

Sathiyadevi, G., B. Loganathan, and B. Karthikeyan. "Solvent-Mediated Eco-Friendly Synthesis and Characterization of Monodispersed Bimetallic Ag/Pd Nanocomposites for Sensing and Raman Scattering Applications." Journal of Nanoscience 2014 (April 13, 2014): 1–9. http://dx.doi.org/10.1155/2014/762453.

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The solvent-mediated eco-friendly monodispersed Ag/Pd bimetallic nanocomposites (BNCs) having thick core and thin shell have been prepared through novel green chemical solvent reduction method. Reducing solvent, dimethyl formamide (DMF) is employed for the controlled green synthesis. Characterization of the synthesized Ag/Pd BNCs has been done by x-ray diffraction (XRD) studies, high-resolution scanning electron microscopy (HR-SEM), energy-dispersive X-ray analysis (EDX), and high-resolution transmission electron microscopy (HR-TEM) with selected area electron diffraction (SAED) pattern. The nature of the interaction of L-cysteine with Ag/Pd BNCs has been studied by using surface plasmon spectroscopy, Fourier transform-infrared spectroscopy (FT-IR), cyclic voltammetry (CV), and theoretical methods.

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Yu, Ling Min, Xin Hui Fan, Jing Yi Shui, Lei Cao, and Wen Yan. "Fabrication of SnO₂/Zn₂SnO₄/ZnO Nanocables through Thermal Oxidation of Zn and Sn Mixture Powders." Advanced Materials Research 532-533 (June 2012): 70–73. http://dx.doi.org/10.4028/www.scientific.net/amr.532-533.70.

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We demonstrate the synthesis of a three-layer-coaxial SnO2/ZnSn2O4/ZnO core–shell nanocable heterostructures with diameters 80-150 nm via thermal oxidation of Zn and Sn mixture powders. The products are characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRD) and field emission transmission electron microscopy (TEM). The structural analysis shows the formation of ZnSnO4 in the interface region between the SnO2 core and ZnO shell, which is resulted from inter－diffusion of Sn and Zn ions during thermal evaporation. The selected area electron diffraction (SAED) pattern was composed of two series of overlapped polycrystalline rings attributed to SnO2 and Zn2SnO4, one set of hexahedron diffraction spots that can be indexed to the hexagonal ZnO. On the basis of investigation of the microstructures, the possible formation mechanism of Zn2SnO4 is discussed.

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Silva, Nataly, Sara Ramírez, Isaac Díaz, Andreina Garcia, and Natalia Hassan. "Easy, Quick, and Reproducible Sonochemical Synthesis of CuO Nanoparticles." Materials 12, no. 5 (March 8, 2019): 804. http://dx.doi.org/10.3390/ma12050804.

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Copper oxide nanoparticles (CuO NPs) were synthesized in air by reducing copper (II) sulfate pentahydrate salt (CuSO4·5H2O) in the presence of sodium borohydride. The reaction was stabilized with Hexadecyltrimethylammonium bromide (CTAB) in a basic medium and using ultrasound waves. Different molar ratios of CTAB:Cu2+ and NaBH4:Cu2+ were explored, to optimize the synthesis conditions, and to study the stability, size, and Zeta potential of the colloidal suspension. Optimum conditions to generate spherical, stable, and monodispersed nanoparticles with hydrodynamic diameters of 36 ± 1.3 nm were obtained, using 16 mM CTAB and 2 M NaBH4 (molar ratios Cu2+:CTAB:NaBH4 of 1:6:10). X-ray diffraction (XRD) was implemented, and a monoclinic CuO crystal system was formed. This demonstrated a monoclinic crystal system corresponding to CuO. The diffraction peaks were identified and confirmed according to their selected area electron diffraction (SAED) patterns.

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Mkhize, Senzosenkosi Surprise, Ofentse Jacob Pooe, Sandile Khoza, Ishmael Nkoana Mongalo, Rene Khan, and Mthokozisi Blessing Cedric Simelane. "Characterization and Biological Evaluation of Zinc Oxide Nanoparticles Synthesized from Pleurotus ostreatus Mushroom." Applied Sciences 12, no. 17 (August 26, 2022): 8563. http://dx.doi.org/10.3390/app12178563.

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This study aimed to biosynthesize zinc oxide nanoparticles (ZnO NPs) using Pleurotus ostreatus to achieve a simple ecofriendly method, and further evaluate antimicrobial activity and cytotoxicity towards HepG2 and Hek293 cells. The nanoparticles were characterized through UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), transmission and scanning electron microscopy (TEM and SEM), selected area electron diffraction (SAED), X-ray diffraction (XRD), and dynamic light scattering (DLS). The minimal inhibitory concentration (MIC) for antimicrobial activity and MTT assay for cytotoxicity were conducted in vitro. The study revealed an efficient, simple, and ecofriendly method for synthesis of ZnO NPs that have antimicrobial activity. UV-Vis showed peaks at 340 and 400 nm, and the bioactive compounds found in the mushroom acted as capping, reducing, and stabilizing agents. TEM characterized NPs as an amorphous nanosheet, with preferential orientation as projected by SAED patterns. The spherical and agglomerated morphology was observed on SEM, with EDX proving the presence of Zn and O, while XRD indicated a crystallite size of 7.50 nm and a stable nature (zeta potential of −23.3 mV). High cytotoxicity on Hek293 and HepG2 cells was noted for ZnO NPs. The study provides an alternative, ecofriendly method for biosynthesis of ZnO NPs that have antibacterial activity and potential use in cancer treatment.

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Статті в журналах з теми "Selected Area Electron Diffraction (SAED) Patterns"

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