Journal articles: 'High Resolution Scanning Electron Microscopy (HRSEM)'

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Apkarian, Robert P. "Comments on Cryo High Resolution Scanning Electron Microscopy." Microscopy Today 12, no. 1 (January 2004): 45. http://dx.doi.org/10.1017/s1551929500051841.

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Stephen Carmichael wrote about Cryoelectron Tomography in the May 2003 issue of Microscopy Today. Citing new preparation methods, small cells can be vitrified, observed frozen in the TEM and a series of digital images captured while the specimen is being rotated around the axis perpendicular to the electron beam producing a 3-D tomogram. Gina Sosinski and Maryann Martone wrote about imaging big and messy biological structures using cryo-electron Tomography in the July issue of Microscopy Today. Cryo-HRSEM now also seeks to provide 3-D information approaching the molecular level from frozen hydrated cell and molecular systems. Vitrification procedures for small specimens such as platelets and biomolecules on grids are accomplished by plunge freezing in liquefied etiiane as is done with cryo-TEM procedures. Bulk specimens such as organic hydrogels and tissues are routinely high pressure frozen (HPF) in 3mm gold planchets. Employing an in-lens cryostage, identical to those used in cryo-TEM, cryo-HRSEM provides 3-D high-resolution images because secondary electrons are efficiently collected above the lens in a single scan thus minimizing specimen irradiation.

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Vezie, Deborah L. "High-resolution scanning electron microscopy of carbon fiber." Proceedings, annual meeting, Electron Microscopy Society of America 47 (August 6, 1989): 704–5. http://dx.doi.org/10.1017/s0424820100155499.

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As part of an extensive study of polyacrylonitrile (PAN) and mesophase pitch-based carbon fibers, high resolution scanning electron microscopy (HRSEM) is shown to provide additional insight into understanding and modelling microstructural origins of mechanical properties of carbon fiber. Although carbon fiber has been studied extensively, no sufficiently clear relationship between structure and mechanical properties such as elastic modulus and compressive strength has yet been developed from quantitative TEM and WAXS investigations.In this study, HRSEM data of selected carbon fibers is used to illustrate the power of HRSEM to elucidate structural differences likely accounting for changes in mechanical properties not sensitively probed either by TEM or WAXS. The three-dimensional nature of SEM imaging with accompanying high resolution permits a clearer visualization and more detailed examination of regional structures within carbon fiber over two-dimensional TEM and globally averaged WAXS data.The design of the high resolution, field emission SEM permits low voltage imaging of poorly conducting samples with resolution an order of magnitude greater than a conventional tungsten hairpin filament SEM under the same operating voltage and sample preparation conditions. Although carbon fiber is a relatively conductive material, charging effects can be seen in uncoated PAN fibers above 3.0 keV in a conventional SEM. Lower accelerating voltages are necessary for uncoated imaging of these fibers, but become impractical due to degradation of conventional SEM performance at these voltages. Uncoated sample imaging is preferred to prevent conventional evaporation or sputter coating techniques from obscuring or altering the sample surface, although charging effects may then be a problem. The high resolution, field emission SEM solves these competing voltage/ charging/ resolution issues for poorly conducting materials with the very nature of its design; the high brightness of the electron gun at low voltage coupled with the “in lens” sample placement and above the objective lens detector dramatically improve the resolution of these instruments, especially at low voltage.

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Cosandey, F. "High Spatial Resolution EBSD Study of Nanosized Epitaxial Particles." Microscopy and Microanalysis 3, S2 (August 1997): 559–60. http://dx.doi.org/10.1017/s1431927600009685.

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Traditionally, the structure and orientation relationship of individual catalyst particles on various oxide substrates have been studied by transmission electron microscopy. However, the combination of high resolution scanning electron microscopes (HRSEM) equipped with Schottky field emission sources with CCD cameras for recording electron backscatter diffraction (EBSD) paterns, it is now possible to obtain both morpholgy and orientation of individual particles with high spatial resolution. In this paper, we present results on the application of combined EBSD with HRSEM to determine the epitaxial orientation relationship of 80 nm Au particles on TiO2 (110). An evaluation of the spatial resolution limit of EBSD using Monte Carlo simulation of backscattered electron trajectories is also presented.The TiO2 (110) single crystal surfaces used in this study were prepared in UHV using surface science tools followed by in-situ metallization. After deposition of 15 nm Au at 300K followed by annealing at 800K, the samples were transferred in air to the Field Emission Scanning Electron microscope (LEO 982 Gemini) for high resolution imaging.

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Cosandey, F., L. Zhang, and T. E. Madey. "High Resolution Fesem Study of Au Particle Growth on TiO2." Microscopy and Microanalysis 3, S2 (August 1997): 405–6. http://dx.doi.org/10.1017/s1431927600008916.

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Transition metals supported on oxides have important catalytic properties and are also used in chemical gas sensors for increasing sensitivity and selectivity. In order to understand growth and reactivity in the Au/TiO2 system, we have performed surface studies on a model system consisting of ultrathin, discontinuous Au films on TiO2 (110) single crystals. In this paper we are presenting results obtained by high resolution scanning electron microscopy (HRSEM) on the effects of substrate temperature and average Au thickness on particle size, density and coverage.The TiO2 (110) single crystal surfaces used in this study were prepared in UHV using surface science tools followed by in-situ Au deposition for different substrate temperatures and for various film thicknesses. After deposition, the samples were transferred in air to the Field Emission Scanning Electron microscope (LEO 982 Gemini) for high resolution imaging.Typical high resolution scanning electron microscopy (HRSEM) images of Au films deposited at 300 K are shown in Fig. 1 for two film thicknesses of 0.22 and 1.0 nm.

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Chen, Ya, Geoffrey Letchworth, and John White. "Progress in high-resolution CRYO-SEM imaging of viral particles." Proceedings, annual meeting, Electron Microscopy Society of America 54 (August 11, 1996): 818–19. http://dx.doi.org/10.1017/s0424820100166555.

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Low-temperature high-resolution scanning electron microscopy (cryo-HRSEM) has been successfully utilized to image biological macromolecular complexes at nanometer resolution. Recently, imaging of individual viral particles such as reovirus using cryo-HRSEM or simian virus (SIV) using HRSEM, HV-STEM and AFM have been reported. Although conventional electron microscopy (e.g., negative staining, replica, embedding and section), or cryo-TEM technique are widely used in studying of the architectures of viral particles, scanning electron microscopy presents two major advantages. First, secondary electron signal of SEM represents mostly surface topographic features. The topographic details of a biological assembly can be viewed directly and will not be obscured by signals from the opposite surface or from internal structures. Second, SEM may produce high contrast and signal-to-noise ratio images. As a result of this important feature, it is capable of visualizing not only individual virus particles, but also asymmetric or flexible structures. The 2-3 nm resolution obtained using high resolution cryo-SEM made it possible to provide useful surface structural information of macromolecule complexes within cells and tissues. In this study, cryo-HRSEM is utilized to visualize the distribution of glycoproteins of a herpesvirus.

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Lea, P. J., and M. J. Hollenberg. "High-resolution scanning electron microscopy (HRSEM) of mitochondria from various rat tissues." Proceedings, annual meeting, Electron Microscopy Society of America 46 (1988): 14–15. http://dx.doi.org/10.1017/s0424820100102158.

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Our current understanding of mitochondrial ultrastructure has been derived primarily from thin sections using transmission electron microscopy (TEM). This information has been extrapolated into three dimensions by artist's impressions (1) or serial sectioning techniques in combination with computer processing (2). The resolution of serial reconstruction methods is limited by section thickness whereas artist's impressions have obvious disadvantages.In contrast, the new techniques of HRSEM used in this study (3) offer the opportunity to view simultaneously both the internal and external structure of mitochondria directly in three dimensions and in detail.The tridimensional ultrastructure of mitochondria from rat hepatocytes, retinal (retinal pigment epithelium), renal (proximal convoluted tubule) and adrenal cortex cells were studied by HRSEM. The specimens were prepared by aldehyde-osmium fixation in combination with freeze cleavage followed by partial extraction of cytosol with a weak solution of osmium tetroxide (4). The specimens were examined with a Hitachi S-570 scanning electron microscope, resolution better than 30 nm, where the secondary electron detector is located in the column directly above the specimen inserted within the objective lens.

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Bentley, J., N. D. Evans, and E. A. Kenik. "Measurement of Scanning Electron Microscope resolution." Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 1044–45. http://dx.doi.org/10.1017/s0424820100172954.

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The resolution performance of a scanning electron microscope (SEM) is a primary specification of the instrument. For a high-resolution SEM (HRSEM) equipped with a field emission gun (FEG), image resolutions of less than 2 nm are commonly claimed. Generally, both manufacturers and customers identify image resolution as the single most important performance criterion. It is traditionally determined with specimens such as gold islands on bulk carbon supports, where the minimum apparent separation of two islands is claimed as the resolution. This procedure is highly subjective since the spacings are not known independently. Dodson and Joy have pointed out the paradox implicit in this approach-that “the resolution of a given instrument can be verified only after a better instrument is available to characterize the structure spacing.” By analogy to the now standard approach for high-resolution transmission electron microscopes (TEMs), Dodson and Joy investigated the use of Fourier Transforms (FT) of high-resolution SEM images for measuring resolution.

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Apkarian, Robert P. "Introduction: High Resolution Cryo-SEM in the Biological Sciences." Microscopy and Microanalysis 9, no. 4 (August 2003): 272. http://dx.doi.org/10.1017/s143192760303054x.

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What is cryogenic high resolution (in-lens) scanning electron microscopy (HRSEM), and do I need it? Structural cell biologists and bioorganic chemists will find this newly developed imaging mode to be an accurate and useful research tool for molecular level investigations in the hydrated state.

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Simmons, S. R., S. J. Eppell, R. E. Marchant, and R. M. Albrecht. "Correlative atomic-force microscopy and high-resolution scanning electron microscopy of proteins attached to platelet surfaces." Proceedings, annual meeting, Electron Microscopy Society of America 51 (August 1, 1993): 230–31. http://dx.doi.org/10.1017/s0424820100146990.

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The atomic force microscope (AFM) has provided images at submolecular or atomic scale resolution of biological macromolecules attached to surfaces such as mica, graphite, or synthetic phospholipid membranes. Because the AFM can be operated with the sample in air, vacuum, or immersed in a liquid such as a biological buffer, it has the potential for high resolution imaging of the structure and organization of macromolecules on surfaces of cells in the hydrated or even living state. Realization of this potential would allow observation of molecular processes at the cell surface without the necessity for preparation of the sample for electron microscopy. To date, however, the AFM has yielded images of cell surfaces only at relatively low magnifications, and has not provided the atomic resolution achieved on hard, crystalline surfaces.Previously we have utilized correlative video-enhanced light microscopy, high voltage transmission electron microscopy, and low voltage, high resolution scanning electron microscopy (HRSEM)

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Sutrisno, H., E. D. Siswani, and K. S. Budiasih. "The effect of sintering temperatures of TiO2(B)-nanotubes on its microstructure." Science of Sintering 50, no. 3 (2018): 291–98. http://dx.doi.org/10.2298/sos1803291s.

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Titanium dioxide (TiO2)-nanotubes were prepared by a simple technique reflux. The morphologies and microstructures of nanotubes were characterized by high resolution scanning electron microscopy (HRSEM), high resolution transmission electron microscopy (TEM), powder X-ray diffraction (XRD,) energy dispersive X-ray spectroscopy (EDS) and surface area analyzer. The microstructures of TiO2 phases obtained from the sintering process of TiO2-nanotubes for 1 hour at various temperatures from 100 to 1000?C at intervals of 50?C were investigated from the XRD diffractograms. The analyses of morphologies and microstructures from HRSEM and HRTEM images describe the sample as nanotubes. The nanotube is single phase exhibiting TiO2(B) structure. The XRD patterns show that TiO2(B)-nanotubes transform into anatase phase and then become rutile due to increasing sintering temperatures.

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Apkarian, Robert P. "An in-lens cryostage for high-resolution secondary-I and scanning transmission electron microscopy." Proceedings, annual meeting, Electron Microscopy Society of America 54 (August 11, 1996): 816–17. http://dx.doi.org/10.1017/s0424820100166543.

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A newly designed cryo-holder was built for the in-lens top stage of a Topcon DS-130 field emission scanning transmission and high resolution secondary electron-I microscope (STEM/HRSEM). The modified Oxford CT-3500 cryo-holder was designed to fit into the narrow bore in-lens of the DS-130F. The cryo-holder was designed to shuttle from the freezing chamber, to the high vacuum chamber of the Denton DV-602 magnetron sputter system for metal coating, and then to the interlock of the DS-130F upper stage. The intention was to provide a single cryo-holder to image frozen specimens by either HRSEM or STEM modes. In this electron optical design, many specimens, prepared by different cryo-preparation procedures, could be imaged by either or both imaging modes. The upper stage of the DS-130F was modified to accept a second liquid nitrogen (LN2) cold trap and a Varian cold cathode ion discharge gauge for monitoring the vacuum at the specimen (Fig. 1).

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Liu, J., G. E. Spinnler, and A. E. Ron. "Imaging small particles with secondary electrons." Proceedings, annual meeting, Electron Microscopy Society of America 50, no. 2 (August 1992): 1288–89. http://dx.doi.org/10.1017/s0424820100131073.

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High resolution secondary electron microscopy (HRSEM) in dedicated scanning transmission electron microscopy (STEM) instruments has proved very useful for characterizing supported catalysts. In order to understand the contrast mechanisms of HRSEM images of small particles, clean samples and UHV environments are needed since the emission of secondary electrons (SEs) can be significantly influenced by contamination on the particle surface. In this paper we report results on imaging small metal particles by HRSEM in a UHV STEM instrument. In addition, we show that with computer assistance digitized HRSEM images of small metal particles can be used to estimate the average inelastic mean free path and the mean escape depth of the collected SEs.The Vacuum Generators UHV STEM HB-501S, codenamed MIDAS (a Microscope for Imaging, Diffraction and Analysis of Surfaces), was used for these experiments. Detailed descriptions of the MIDAS system have been published previously. The collection efficiency of SEs approaches 100% through the use of magnetic ‘parallelizers’ situated inside the objective pole pieces.

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Saleh, Hoda H., Rehab Sokary, and Zakaria I. Ali. "Radiation – induced preparation of polyaniline/poly vinyl alcohol nanocomposites and their properties." Radiochimica Acta 107, no. 8 (July 26, 2019): 725–35. http://dx.doi.org/10.1515/ract-2018-3003.

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Abstract Polyaniline (PANI) nanoparticles and PANI/poly vinyl alcohol (PVA) nanocomposite films were synthesized by the oxidative polymerization of aniline and ammonium peroxodisulfate (APS), as an oxidizing agent in aqueous medium. The PANI/PVA nanocomposite films were exposed to γ-irradiation after oxidative polymerization. Synthesized polyaniline (PANI) nanoparticles and PANI/PVA nanocomposite films were characterized by attenuated total reflectance infrared spectroscopy (FTIR-ATR), X-ray diffraction, high resolution scanning electron microscopy, (HRSEM) high resolution transmission electron microscopy, (HRTEM) and UV-VIS absorption spectroscopy. Energy band gap of PANI nanofibers was determined from Tauc’s plots which equal 4.2 eV. Scanning electron microscopy images show that chemically synthesized of polyaniline has nanofibers structure and irradiated PANI/PVA nanocomposite have a mixture of nanorod and nanosphere structures. The transmission electron microscopy show that chemically synthesized of polyaniline has average length in the range 34 ± 10 nm with less wide distribution, where as the irradiated PANI/PVA nanocomposite has coreshell structure.

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Castejón, Orlando J. "Scanning Electron Microscopy Study of Cerebellar Synaptic Junctions." Proceedings, annual meeting, Electron Microscopy Society of America 48, no. 3 (August 12, 1990): 148–49. http://dx.doi.org/10.1017/s0424820100158285.

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Conventional and high resolution scanning electron microscopy have been applied to trace short cerebellar nerve circuits and to explore the outer and inner surfaces of spine, glomerular and axodendritic synapses. Samples of teleost fishes (Arius spixii and Salmo Trutta) cerebellar cortex were processed according to the slicing technique for conventional scanning electron microscopy (SEM), ethanol cryofracturing technique and freeze-fracture scanning electron microscopy (FFSEM) (Castejón, 1988). Primate (Rhesus monkey) cerebellar cortex was processed for high resolution scanning electron microscopy (Castejón and Apkarian, 1990), according to the protocol of delicate specimen preparation (Peters, 1980). Observations were made in JEOL 100B with (ASID), scanning attachment ISI DS-130 equiped with LaB6 emitter and Hitachi S-900 SEM with a cold cathode field emitter. Micrographs for HRSEM were soft focus printed to reduce instrumental noise (Peters, 1985). A comparison was made of gold-palladium and chromium coating cerebellar samples.The slicing technique and the cryofracture process exposed the neuronal outer surface revealing hidden surface ensheathed by neuroglial cells.

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Riva, Alessandro, Felice Loffredo, Alessandro Uccheddu, Francesca Testa Riva, and Bernard Tandler. "Mitochondria of Human Adrenal Cortex Have Tubular Cristae with Bulbous Tips." Journal of Clinical Endocrinology & Metabolism 88, no. 4 (April 1, 2003): 1903–6. http://dx.doi.org/10.1210/jc.2002-030013.

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By taking advantage of a modified osmium maceration technique, we have been able to examine by high resolution scanning electron microscopy (HRSEM) the interior of human adrenocortical mitochondria from which all soluble material has been extracted. The so-called vesicles apparent in thin sections examined by transmission electron microscopy actually are finger-like cristae as determined by HRSEM. These digitiform cristae have a segmented appearance and a bulbous tip. The segmented form of the cristae may have important metabolic implications.

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Lea, Peter J., Robert J. Temkin, Karl B. Freeman, Grant A. Mitchell, and Brain H. Robinson. "Variations in mitochondrial ultrastructure and dynamics observed by high resolution scanning electron microscopy (HRSEM)." Microscopy Research and Technique 27, no. 4 (March 1, 1994): 269–77. http://dx.doi.org/10.1002/jemt.1070270402.

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Lea, P. J., R. J. Temkin, T. Banoub, M. Silverman, and M. J. Hollenberg. "Investigation of the tridimensional ultrastructure of rat glomerular capillary endothelium by high-resolution scanning electron microscopy." Proceedings, annual meeting, Electron Microscopy Society of America 48, no. 3 (August 12, 1990): 30–31. http://dx.doi.org/10.1017/s0424820100157681.

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The principal applications of scanning electron microscopy (SEM) to renal ultrastructure have been in the study of the surface topography of various kidney cell types and their orientation and distribution in both health and disease. SEM study, however, has been limited in a major way by a lack of resolution sufficient to readily examine in detail and in three dimensions such features as glomerular basement membrane substructure and the structural organization at high magnification of the glomerular, capillary endothelium. Consequently, most of our current information about the 3D ultrastructure of rat kidney glomerulus has been obtained from transmission electron (TEM) micrographs obtained from thin sections cut at various planes followed by computer assisted, serial reconstructions. Recent advances in specimen preparation techniques and scanning electron microscope design have permitted ultrastructural examination of the glomerular capillary wall in three dimensions using high resolution scanning electron microscopy (HRSEM). Specimens in which the cytosol and cytoskeleton have been extracted, but cell membranes nuclear structures and organelles left in place, were studied using a Hitachi SEM with a resolution of approximately 3 nm.

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Chan, L., T. Yamashita, and R. Sinclair. "Transmission electron microscopy and high resolution scanning electron microscopy of Co-Ni-Pt thin film magnetic recording media." Proceedings, annual meeting, Electron Microscopy Society of America 47 (August 6, 1989): 570–71. http://dx.doi.org/10.1017/s0424820100154822.

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In thin film magnetic media, the magnetic hysteresis properties and micromagnetic domain behavior are strongly influenced by both interparticle exchange interactions and by magnetostatic interactions. The exchange interactions are short-range in nature; therefore, they are very sensitive to interparticle separation. Consequently, the magnetic hysteresis properties and the recording behavior of the thin film magnetic media can be drastically altered by the introduction of grain separation during the film deposition process. In this study, thin film media of a CoNiPt alloy of one composition was processed under two different conditions. Transmission electron microscopy (TEM) and high resolution scanning electron microscopy (HRSEM) were used to investigate and explain the difference in magnetic hysteresis characteristics of the films.The structure of the thin film media consisted of a 600 Å thick CoNiPt alloy sputtered on textured 130mm diameter NiP-plated aluminum substrates. A single sputtering parameter was varied to produce two types of films, labelled type I and type II, which exhibited significant differences in their magnetic recording characteristics.

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Reichelt, R., U. Aebi, and A. Engel. "An Efficient Annular Dark-Field Detector Capable of Single-Electron Counting Adapted to a High-Resolution Field-Emission SEM." Proceedings, annual meeting, Electron Microscopy Society of America 46 (1988): 190–91. http://dx.doi.org/10.1017/s0424820100103036.

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Various high resolution scanning electron microscopes (HRSEM) are now commercially available providing probe sizes in the range of 0.5 to 1.5 nm at 30 keV due to their field emission gun 1.2. Equipped with efficient detector systems (which collect different signals and applied to specifically prepared samples) HRSEM challenge the conventional transmission electron microscope (TEM) with high resolution surface images of biological specimens collecting secondary (SE) or backscattered (BSE) electrons. However, the yield of (SE) carrying high resolution information is rather small, i.e. the SE-I yield at 20 keV primary electron energy amounts to < 1% for the major elements (H; C; N; O; P) constituting biological matter. The yield of BSE is greater than the corresponding total SE yield (electron energy >15 keV), but BSE emerge due to high angle elastic scattering from a surface area with a diameter of typically 30% of the deepest electron penetration R (e.g. R≈10 μm for elements mentioned above at 30 keV).

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Vezie, D. L., W. W. Adams, and E. L. Thomas. "Low-voltage high-resolution SEM: A valuable resource for the polymer morphologist." Proceedings, annual meeting, Electron Microscopy Society of America 51 (August 1, 1993): 868–69. http://dx.doi.org/10.1017/s0424820100150174.

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The elucidation of polymer morphology has historically been accomplished using optical microscopy (OM), conventional transmission electron microscopy (TEM), X-ray scattering and more recently for crystalline polymers, high resolution TEM (HRTEM). Significant work using scanning electron microscopy (SEM) to study synthetic polymers began in the late 1960's, but for twenty years after these first studies, the smallest features imaged by SEM in polymer samples have typically been 1-10 μm. The evolution of the low voltage high resolution SEM (LVHRSEM) now provides polymer scientists with the opportunity to image structures topographically on the order of 50-100 Å, a level of microstructure important in basic polymer physics research. The potential for improved understanding of polymer morphology is significant, especially when HRSEM data is combined with information from other complementary techniques such as TEM, X-ray scattering, and the scanning probe microscopies (SPM, AFM, STM).The advantages of LVHRSEM over conventional thermionic source SEM as a polymer characterization technique include: i) low keV operation reduces or eliminates charging in uncoated insulating polymers, ii) the high brightness, low energy spread, small spot size field emission gun allows for operation at low keV without significant loss of resolution (practically, resolution on the order of 50 Å at 1.0 keV in a polymer sample is attainable), iii) imaging of surface topography is improved at low keV as the beam/sample interaction volume is smaller and closer to the surface, resulting in more secondary electrons being generated within the secondary electron escape depth, and iv) the immersion lens system improves the signal to noise ratio by decreasing the noise component in the secondary electron signal.

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Apkarian, Robert P., Kevin L. Caran, and Keith A. Robinson. "Topographic Imaging of Chromium-Coated Frozen-Hydrated Cell and Macromolecular Complexes by In-Lens Field Emission Scanning Electron Microscopy." Microscopy and Microanalysis 5, no. 3 (May 1999): 197–207. http://dx.doi.org/10.1017/s1431927699000148.

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An in-lens Schottky field emission scanning electron microscope (SEM) combined with a transmission electron microscope (TEM)-type cold-stage and a chromium (Cr) sputter-coating system was developed to rapidly prepare and cryo-image biological specimens to attain accurate nanometer-level structural information. High-resolution topographic images at high primary magnification ([eg ]200,000 times) were digitally recorded with very short dwell times and without beam damage. Plunge freezing in ethane, followed by fracturing, Cr coating, and in-lens cryo-high-resolution scanning electron microscope (HRSEM) imaging directly revealed macromolecular features of yeast cells, platelets, and cell-free elastin analogues. The 'vitreous' nature of bulk water in its solid state appeared featureless in cryo-HRSEM images, suggesting that if ice crystals were present they would be [el ]2–3 nm (the approximate instrument resolution on cryo-specimens). Compared to technically difficult and indirect freeze-fracture TEM replicas, cryo-HRSEM samples are fully hydrated, unfixed, noncryoprotected specimens immersed in featureless ice. The time necessary to cryo-immobilize the specimen and record the image is <3 hr. The hexagonal arrays of intramembrane particles on the protoplasmic face of yeast cells and differences in surface morphology between thrombin-stimulated and quiescent platelets were assessed. A clear interface line between collapsed elastin fibril lacework and vitreous lakes was commonly observed. These experiments demonstrate the feasibility of this technique to rapidly evaluate macromolecular features in cryofixed cells and cell-free systems.

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Ugalde, Magali, E. Chavira, Martha T. Ochoa-Lara, and Carlos Quintanar. "New Synthesis Method to Obtain Pd Nano-Crystals." Journal of Nano Research 14 (April 2011): 93–103. http://dx.doi.org/10.4028/www.scientific.net/jnanor.14.93.

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We report a new synthesis method to obtain palladium nano-crystals by sol-gel polymerized with acrylamide. From thermogravimetric analysis (TGA) studies, we found PdO and Pd compounds in the xerogel sample, at 550 °C, and over 900 °C we detected only metallic Pd. These results were corroborated by powder X-Ray Diffraction (XRD), High Resolution Scanning Electron Microscopy (HRSEM), and Transmission Electron Microscopy (TEM). XRD studies exhibit the lines from the tetragonal structure (PDF 41-1107) of PdO compound and from the cubic structure (PDF 46-1043) of Pd metallic. HRSEM micrographs show morphologies from the sample very sensitive to heat treatment. Finally, TEM images show crystals of ~8 nm in diameter.

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García-Zaleta, D. S., A. M. Torres-Huerta, M. A. Domínguez-Crespo, A. García-Murillo, R. Silva-Rodrigo, and R. López González. "Influence of Phases Content on Pt/TiO2, Pd/TiO2Catalysts for Degradation of 4-Chlorophenol at Room Temperature." Journal of Nanomaterials 2016 (2016): 1–15. http://dx.doi.org/10.1155/2016/1805169.

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Different Pt/TiO2and Pd/TiO2catalysts were prepared by sol-gel method. The influence of different amounts of noble metals (1–5 mol-%) present on the microstructure as well as the photocatalytic property under 4-chlorophenol degradation was evaluated. The anatase phase was favored at low Pt content; however, the apparition of new phases after 3 mol-% (PtO) suggests a saturation lattice considering our solubility limit at 1 mol-%. Similar trend was observed when Pd was added to the TiO2lattice. The as-prepared catalysts were deeply characterized by X-ray diffraction (XRD) with the Rietveld Method, Raman spectroscopy, high resolution scanning electron microscopy (HRSEM), scanning transmission electron microscopy (STEM), Brunauer-Emmett-Teller (BET) adsorption analysis, and X-Ray photoelectron spectroscopy (XPS). Unit-cell parameter of TiO2phases varied from 30 to 93 vol-% depending on the amount of Pt or Pd added to the composite. HRTEM and HRSEM identified the phases in the catalysts and confirmed the nanometric size and morphology of the catalysts. An improvement in removal efficiency of 4-chlorophenol was obtained in all the specimens compared with the commercial Degussa P25, which can be explained in terms of phase composition and modification of the band gap.

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Apkarian, Robert P., Elizabeth R. Wright, Victor A. Seredyuk, Susan Eustis, L. Andrew Lyon, Vincent P. Conticello, and Fredric M. Menger. "In-Lens Cryo-High Resolution Scanning Electron Microscopy: Methodologies for Molecular Imaging of Self-Assembled Organic Hydrogels." Microscopy and Microanalysis 9, no. 4 (August 2003): 286–95. http://dx.doi.org/10.1017/s1431927603030551.

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The micro- and nanoarchitectures of water-swollen hydrogels were routinely analyzed in three dimensions at very high resolution by two cryopreparation methods that provide stable low-temperature specimens for in-lens high magnification recordings. Gemini surfactants (gS), poly-N-isopropylacrylamides (p-NIP Am), and elastin-mimetic di- (db-E) and triblock (tb-E) copolymer proteins that form hydrogels have been routinely analyzed to the sub-10-nm level in a single day. After they were quench or high pressure frozen, samples in bulk planchets were subsequently chromium coated and observed at low temperature in an in-lens field emission SEM. Pre-equilibrated planchets (4–40°C) that hold 5–10 μl of hydrogel facilitate dynamic morphological studies above and below their transition temperatures. Rapidly frozen samples were fractured under liquid nitrogen, low-temperature metal coated, and observed in-lens to assess the dispersion characteristics of micelles and fragile colloidal assemblies within bulk frozen water. Utilizing the same planchet freezing system, the cryoetch-HRSEM technique removed bulk frozen water from the hydrogel matrix by low-temperature, high-vacuum sublimation. The remaining frozen solid-state sample faithfully represented the hydrogel matrix. Cryo- and cryoetch-HRSEM provided vast vistas of hydrogels at low and intermediate magnifications whereas high magnification recordings and anaglyphs (stereo images) provided a three-dimensional prospective and measurements on a molecular level.

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Arumugam, J., A. Dhayal Raj, and A. Albert Irudayaraj. "Morphology Manipulation and Related Properties of High Crystalline Bi2S3 Nanorods by Reflux Approach." Volume 4,Issue 5,2018 4, no. 5 (November 12, 2018): 524–26. http://dx.doi.org/10.30799/jnst.159.18040516.

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One dimensional Bi2S3 nanorods have been successfully synthesized by a very simple reflux method with different precursor concentration for 2 hours at 180 �C. The as-synthesized Bi2S3 powders were characterized by X-ray diffraction (XRD), high resolution scanning electron microscope (HRSEM), high resolution transmission microscope (HRTEM), UV-Vis spectrometer, Fourier transform infrared (FTIR) spectrometer. X-ray diffraction (XRD) results show that the resulting nanocrystals have an orthorhombic structure. X-ray diffraction patterns indicate a polycrystalline nature and the crystallite sizes seem increase with increase in the concentration. The HRSEM and HRTEM images reveal that the diameter of the nanorods increase with increasing concentration of the precursor. Morphological analysis reveals that the as-prepared Bi2S3 nanorods can be tuned to morphology by varying precursor concentration from 0.01 M to 0.001 M. The bismuth nitrate, which is known to be a linear polymer, plays a critical role as a precursor and a template for the growth of uniform Bi2S3 nanorods. Bi2S3 nanorods are good absorbents of solar radiation and hence can be used in solar cells.

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Adams, W. W., G. Price, and A. Krause. "Imaging of polymer single crystals in low-voltage, high-resolution scanning electron microscopy." Proceedings, annual meeting, Electron Microscopy Society of America 48, no. 4 (August 1990): 1106–7. http://dx.doi.org/10.1017/s0424820100178665.

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It has been shown that there are numerous advantages in imaging both coated and uncoated polymers in scanning electron microscopy (SEM) at low voltages (LV) from 0.5 to 2.0 keV compared to imaging at conventional voltages of 10 to 20 keV. The disadvantages of LVSEM of degraded resolution and decreased beam current have been overcome with the new generation of field emission gun SEMs. In imaging metal coated polymers in LVSEM beam damage is reduced, contrast is improved, and charging from irregularly shaped features (which may be unevenly coated) is reduced or eliminated. Imaging uncoated polymers in LVSEM allows direct observation of the surface with little or no charging and with no alterations of surface features from the metal coating process required for higher voltage imaging. This is particularly important for high resolution (HR) studies of polymers where it is desired to image features 1 to 10 nm in size. Metal sputter coating techniques produce a 10 - 20 nm film that has its own texture which can obscure topographical features of the original polymer surface. In examining thin, uncoated insulating samples on a conducting substrate at low voltages the effect of sample-beam interactions on image formation and resolution will differ significantly from the effect at higher accelerating voltages. We discuss here sample-beam interactions in single crystals on conducting substrates at low voltages and also present the first results on HRSEM of single crystal morphologies which show some of these effects.

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Li, W. F., T. Ohkubo, T. Akiya, H. Kato, and K. Hono. "The role of Cu addition in the coercivity enhancement of sintered Nd-Fe-B permanent magnets." Journal of Materials Research 24, no. 2 (February 2009): 413–20. http://dx.doi.org/10.1557/jmr.2009.0041.

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To understand the mechanism of the coercivity enhancement by a trace addition of Cu in Nd-Fe-B sintered magnets, we investigated the microstructure difference between Cu-doped and Cu-free alloys using high resolution scanning electron microscopy (HRSEM), transmission electron microscopy (TEM), and laser assisted three dimensional atom probe (LA-3DAP). From a serial sectioning back scattered electron (BSE) images of the Nd-rich phase obtained by an integration of the focused ion beam (FIB) and HRSEM technique, it was found that Cu addition leads to a continuous formation of Nd-rich thin layers along the grain boundaries. 3DAP analysis has shown that a thin Cu-rich layer with a thickness of approximately 2 nm is present at the interface between the Nd2Fe14B and Nd-rich phase grains.

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Watanabe, Ii-sei, Koichi Ogawa, Marcelo Cavenaghi Pereira da Silva, Aracy Akiko Motoyama, Eduardo Shigueaki Kado, and Ruberval Armando Lopes. "Ultrastructure of the adhesion of bacteria to the epithelial cell membrane of three-day postnatal rat tongue mucosa: a transmission and high-resolution scanning electron microscopic study." Brazilian Dental Journal 18, no. 4 (2007): 320–23. http://dx.doi.org/10.1590/s0103-64402007000400009.

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Togue mucosa surface of 3-day postnatal rats was examined under transmission electron microscopy (TEM) and high-resolution scanning electron microscopy (HRSEM). For HRSEM analysis, the specimens were fixed in the same solution for 24 h, postfixed in 2% osmiun tetroxide, critical-point dried and coated with platinum-palladium. For TEM analysis, the specimens were fixed using modified Karnovsky solution and embedded in Spurr resin. The results revealed the presence of numerous microplicae in the membrane surface of keratinized epithelial cells to which groups of bacteria were attached. These bacteria were staphylococcus and coccus organized either in rows or at random, which were visualized in three-dimensional HRSEM images. At high magnification, the TEM images revealed the adhesion of bacteria to the cell membrane through numerous filamentous structures comprising the glycocalyx. The fine fibrillar structures rising from each bacterium and from cell membrane were clearly seen. These characteristics on bacteria structure may be used for future control or prevention of bacterial diseases and for installation of the oral native flora.

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Krause, S. J., W. W. Adams, and D. C. Joy. "Surface effects in imaging uncoated polymers in low-voltage, high-resolution Scanning Electron Microscopy." Proceedings, annual meeting, Electron Microscopy Society of America 47 (August 6, 1989): 336–37. http://dx.doi.org/10.1017/s0424820100153658.

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It has recently been shown that there are numerous advantages in imaging both coated and uncoated polymers in scanning electron microscopy (SEM) at low voltages (LV) from 0.5 to 2.0 keV compared to imaging at conventional voltages of 10 to 20 keV. The major disadvantages of LVSEM of degraded resolution and decreased beam current have been largely overcome with the new generation of field emission gun SEMs. In imaging metal coated polymers in LVSEM beam damage is reduced, contrast is improved, and charging from irregularly shaped features (which may be unevenly coated) is reduced or eliminated. Imaging uncoated polymers in LVSEM allows observation of the surface with little or no charging and with no alterations of surface features from the metal coating process required for higher voltage imaging. This is particularly important for high resolution (HR) studies of polymers where it is desired to image features 1 to 10 nm in size. Metal sputter coating techniques produce a 10 - 20 nm film that has its own texture which can obscure topographical features of the original polymer surface. In examining uncoated insulating samples at low voltages the effect of sample-beam interactions on image formation and resolution will differ significantly from the effect at higher accelerating voltages. In this study we discuss the nature of sample-beam interactions in uncoated polymers at low voltages and also present results on HRSEM of polymer samples which show some of these effects.

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Dywili, Nomxolisi R., Afroditi Ntziouni, Chinwe Ikpo, Miranda Ndipingwi, Ntuthuko W. Hlongwa, Anne Yonkeu, Milua Masikini, Konstantinos Kordatos, and Emmanuel I. Iwuoha. "Graphene Oxide Decorated Nanometal-Poly(Anilino-Dodecylbenzene Sulfonic Acid) for Application in High Performance Supercapacitors." Micromachines 10, no. 2 (February 11, 2019): 115. http://dx.doi.org/10.3390/mi10020115.

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Graphene oxide (GO) decorated with silver (Ag), copper (Cu) or platinum (Pt) nanoparticles that are anchored on dodecylbenzene sulfonic acid (DBSA)-doped polyaniline (PANI) were prepared by a simple one-step method and applied as novel materials for high performance supercapacitors. High-resolution transmission electron microscopy (HRTEM) and high-resolution scanning electron microscopy (HRSEM) analyses revealed that a metal-decorated polymer matrix is embedded within the GO sheet. This caused the M/DBSA–PANI (M = Ag, Cu or Pt) particles to adsorb on the surface of the GO sheets, appearing as aggregated dark regions in the HRSEM images. The Fourier transform infrared (FTIR) spectroscopy studies revealed that GO was successfully produced and decorated with Ag, Cu or Pt nanoparticles anchored on DBSA–PANI. This was confirmed by the appearance of the GO signature epoxy C–O vibration band at 1040 cm−1 (which decreased upon the introduction of metal nanoparticle) and the PANI characteristic N–H stretching vibration band at 3144 cm−1 present only in the GO/M/DBSA–PANI systems. The composites were tested for their suitability as supercapacitor materials; and specific capacitance values of 206.4, 192.8 and 227.2 F·g−1 were determined for GO/Ag/DBSA–PANI, GO/Cu/DBSA–PANI and GO/Pt/DBSA–PANI, respectively. The GO/Pt/DBSA–PANI electrode exhibited the best specific capacitance value of the three electrodes and also had twice the specific capacitance value reported for Graphene/MnO2//ACN (113.5 F·g−1). This makes GO/Pt/DBSA–PANI a very promising organic supercapacitor material.

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Sezen, Meltem, and Sina Sadighikia. "3D electron microscopy investigations of human dentin at the micro/nano-scale using focused ion beam based nanostructuring." RSC Advances 5, no. 10 (2015): 7196–99. http://dx.doi.org/10.1039/c4ra14364g.

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In this study, high resolution electron microscopy techniques, such as Focused Ion Beam (FIB), Scanning Electron Microscopy (SEM) and High Resolution Transmission Electron Microscopy (HRTEM) allowed for revealing micro/nano features within human dentin with high definition and accuracy.

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32

Goldberg, M. W., and T. D. Allen. "High resolution scanning electron microscopy of the nuclear envelope: demonstration of a new, regular, fibrous lattice attached to the baskets of the nucleoplasmic face of the nuclear pores." Journal of Cell Biology 119, no. 6 (December 15, 1992): 1429–40. http://dx.doi.org/10.1083/jcb.119.6.1429.

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The nuclear envelope (NE) of amphibian oocytes can be readily isolated in relatively structurally intact and pure form and has been used extensively for structural studies. Using high resolution scanning electron microscopy (HRSEM), both surfaces of the NE can be visualized in detail. Here, we demonstrate the use of HRSEM to obtain high resolution information of NE structure, confirming previous data and providing some new information. NEs, manually isolated from Triturus cristatus oocytes, have been mounted on conductive silicon chips, fixed, critical point dried and coated with a thin, continuous film of chromium or tantalum and viewed at relatively high accelerating voltage in a field emission scanning electron microscope with the sample within the objective lens. Both nucleoplasmic and cytoplasmic surfaces of the nuclear pore complexes (NPC) have been visualized, revealing the cytoplasmic coaxial ring, associated particles, central plug/transporter and spokes. The nucleoplasmic face is dominated by the previously described basketlike structure attached to the nucleoplasmic coaxial ring. In Triturus, a novel, highly regular flat sheet of fibers, termed the NE lattice (NEL) has been observed attached to the distal ring of the NPC basket. The NEL appears to be distinct from the nuclear lamina. Evidence for the NEL is also presented in thin TEM sections from Triturus oocytes and GVs and in spread NEs from Xenopus. A model is presented for NEL structure and its interaction with the NPCs is discussed.

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Hou, S. M., M. Ouyang, L. Lin, Z. Q. Xue, W. J. Yang, H. Y. Chen, and H. X. Zhang. "A Novel Organic Complex Thin Film for Rewritable Optical Storage." Journal of Materials Research 14, no. 4 (April 1999): 1634–37. http://dx.doi.org/10.1557/jmr.1999.0219.

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Erasable optical storage on an organic complex thin film m-nitrobenzal malononitrile and diamine benzene (m-NBMN/DAB) has been demonstrated. High contrast pattern can be produced by 780 nm laser pulses and can be erased by heating. The static optical recording characteristics were studied by the homemade static characterizer, and the structural properties of the thin films were investigated by the high resolution scanning electron microscope (HRSEM) and transmission electron microscope (TEM).

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Sethy, Naresh Kumar, Zeenat Arif, Pradeep Kumar Mishra, and Pradeep Kumar. "Green synthesis of TiO2 nanoparticles from Syzygium cumini extract for photo-catalytic removal of lead (Pb) in explosive industrial wastewater." Green Processing and Synthesis 9, no. 1 (February 17, 2020): 171–81. http://dx.doi.org/10.1515/gps-2020-0018.

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AbstractGreen synthesis is a simple, non-toxic, economical and eco-friendly approach for the synthesis of nanoparticles. In the present work, nanoparticles of titanium dioxide (TiO2 NPs) were synthesized using an aqueous solution of Syzygium cumini leaf extract as a capping agent. These green synthesized TiO2 NPs were further evaluated for photo catalytic removal of lead from industrial wastewater. Obtained nanoparticles were characterized using: high-resolution scanning electron microscopy (HRSEM), high-resolution transmission electron microscopy (HRTEM), X-ray energy dispersive spectroscopy (EDS), Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), dynamic light scattering (DLS) and Brunauer-Emmett-Teller (BET). Obtained results revealed that synthesized TiO2 NPs possess spherical morphology with anatase phase with a large BET surface area of 105 m2/g. Photo catalytic studies of TiO2 NPs for lead removal from explosive wastewater were performed in a self-designed reactor. Inductive coupled plasma spectroscopy (ICP) was used to determine the lead concentration. Obtained results witnessed 75.5% removal in chemical oxygen demand (COD) and 82.53% removal in lead (Pb2+). This application of green TiO2 NPs is being explored for the first time.

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Stroppa, Daniel G., Luiz F. Zagonel, Luciano A. Montoro, Edson R. Leite, and Antonio J. Ramirez. "High-Resolution Scanning Transmission Electron Microscopy (HRSTEM) Techniques: High-Resolution Imaging and Spectroscopy Side by Side." ChemPhysChem 13, no. 2 (January 13, 2012): 437–43. http://dx.doi.org/10.1002/cphc.201100729.

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TAKIZAWA, Shigeru, and Yoshiki OHNO. "Sample Preparation for Observation with High Resolution Scanning Electron Microscope (HRSEM) by Ion-beam Sputter Coating." Journal of the Mineralogical Society of Japan 28, no. 2 (1999): 65–69. http://dx.doi.org/10.2465/gkk1952.28.65.

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37

Mekhantseva, Tamara, Oleg Voitenko, Ilya Smirnov, Evgeny Pustovalov, Vladimir Plotnikov, Boris Grudin, and Alexey Kirillov. "TEM and STEM Electron Tomography Analysis of Amorphous Alloys CoP-CoNiP System." Advanced Materials Research 590 (November 2012): 9–12. http://dx.doi.org/10.4028/www.scientific.net/amr.590.9.

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This paper covers the analysis of amorphous alloys CoP-CoNiP system by means of high-resolution transmission electron microscopy (HRTEM), scanning transmission electron microscopy and electron tomography. The last years have seen a sufficient progress in the analysis of nanomaterials structure with the help of high resolution tomography. This progress was motivated by the development of microscopes equipped with aberration correctors and specialized sample holders which allow reaching the tilts angles up to ±80°. The opportunities delivered by the method of electron tomography sufficiently grow when producing high resolution images and using chemical analysis, such as X-Ray energy-dispersive microanalysis and electron energy loss spectroscopy (EELS).

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Wu, Chia-Wen, Yusuke Yamauchi, Tetsu Ohsuna, and Kazuyuki Kuroda. "Structural study of highly ordered mesoporous silica thin films and replicated Pt nanowires by high-resolution scanning electron microscopy (HRSEM)." Journal of Materials Chemistry 16, no. 30 (2006): 3091. http://dx.doi.org/10.1039/b604062d.

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Seyring, Martin, Xiaoyan Song, Andrey Chuvilin, Ute Kaiser, and Markus Rettenmayr. "Characterization of grain structure in nanocrystalline gadolinium by high-resolution transmission electron microscopy." Journal of Materials Research 24, no. 2 (February 2009): 342–46. http://dx.doi.org/10.1557/jmr.2009.0071.

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A method is presented for recognition of nanograins in high-resolution transmission electron microscope (HRTEM) images of nanocrystalline materials. We suggest a numerical procedure, which is similar to the experimental dynamic hollow cone dark-field method in transmission electron microscopy and the annular dark-field method in scanning transmission electron microscopy. The numerical routine is based on moving a small mask along a circular path in the Fourier spectrum of a HRTEM image and performing at each angular step an inverse Fourier transform. The procedure extracts the amplitude from the Fourier reconstructions and generates a sum picture that is a real space map of the local amplitude. From this map, it is possible to determine both the size and shape of the nanograins that satisfy the selected Bragg conditions. The possibilities of the method are demonstrated by determining the grain size distribution in gadolinium with ultrafine nanocrystalline grains generated by spark plasma sintering.

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Ma, Jing Ling, Jiu Ba Wen, and Yan Fu Yan. "HRTEM Investigation of Precipitates in Al-Zn-In-Mg-Ti-Ce Anode Alloy." Advanced Materials Research 189-193 (February 2011): 1036–39. http://dx.doi.org/10.4028/www.scientific.net/amr.189-193.1036.

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The precipitates of Al-5Zn-0.02In-1Mg-0.05Ti-0.5Ce (wt %) anode alloy were studied by scanning electron microscopy, X-ray microanalysis, high resolution transmission electron microscopy and selected area electron diffraction analyses in the present work. The results show that the alloy mainly contains hexagonal structure MgZn2 and tetragonal structure Al2CeZn2 precipitates. From high resolution transmission electron microscopy and selected area electron diffraction, aluminium, Al2CeZn2 and MgZn2 phases have [0 1 -1]Al|| [1 -10]Al2CeZn2|| [-1 1 0 1]MgZn2orientation relation, and Al2CeZn2 and MgZn2 phases have the [0 2 -1]Al2CeZn2|| [0 1 -10]MgZn2orientation relation.

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41

Gayou, V. L., B. Salazar Hernández, R. Delgado Macuil, G. Zavala, P. Santiago, and A. I. Oliva. "Structural Studies of ZnS Nanoparticles by High Resolution Transmission Electron Microscopy." Journal of Nano Research 9 (February 2010): 125–32. http://dx.doi.org/10.4028/www.scientific.net/jnanor.9.125.

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Zinc sulfide (ZnS), a representative of wide band gap semiconductor nanocrystals, has an excitonic Bohr radius (aBZnS ) of 2.5 nm. It makes ZnS nanoparticles (ZnS NP) having such size very interesting as small biomolecular probes for fluorescence and laser scanning microscopy. To date, ZnS NP of diameters larger than aBZnS has been subject of extensive experimental and theoretical studies. However many questions remain open concerning the synthesis of undoped and uncapped ZnS NP of diameters less than 2.5 nm. To further probe into the physical properties of undoped and uncapped ZnS NP, in this work we report on studies of uncapped ZnS nanoparticles synthesized by a wet chemical process at room temperature. Three colloidal suspensions (named A, B and C, respectively) were obtained from 9:1, 1:1 and 1:9 volume mixtures of 1mM ZnSO4 and 0.85mM Na2S aqueous solutions. Qualitative differences in UV-Vis absorption spectra are discussed in the context of Z-contrast scanning transmission electron microscopy (Z-contrast), low and high resolution transmission electron microscopy (TEM) results. Distribution of particle size is dependent on different volumes of source solutions. For the intermediate mixture, it has been found that about 78% of ZnS nanoparticles have a diameter smaller than the excitonic Bohr Radius of 2.5 nm. HRTEM studies have revealed that nanoparticles grow preferentially with hexagonal structure.

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Brydson, Rik, Peter C. Twigg, Fiona Loughran, and Frank L. Riley. "Influence of CaO–SiO2 ratio on the chemistry of intergranular films in liquid-phase sintered alumina and implications for rate of erosive wear." Journal of Materials Research 16, no. 3 (March 2001): 652–65. http://dx.doi.org/10.1557/jmr.2001.0120.

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Polycrystalline aluminas sintered with 10 wt% additions of calcium oxide (CaO) and silica (SiO2) in varying molar ratios were fabricated via precipitation, calcination, and hot pressing. Alumina microstructures were analyzed by scanning electron microscopy in terms of their mean grain size, grain size distribution, and grain aspect ratios. High-resolution transmission electron microscopy (HRTEM) showed the presence of an amorphous intergranular glassy phase at two- and three-grain boundaries. The intergranular film width at two-grain boundaries, determined by HRTEM, appeared to vary with the [CaO]:[SiO2] ratio of the additive as did the chemical composition and local chemistry, determined by high-resolution analytical transmission electron microscopy and scanning transmission electron microscopy (using both energy dispersive x-ray and electron energy loss spectroscopy). The factors influencing the erosive wear rate are discussed including the chemistry and associated fracture energy of the intergranular glassy film. Wet erosive wear rates of the densified materials were determined and had a strong dependence on the [CaO]:[SiO2] ratio in the additive.

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Shi, Zhen Xue, Jia Rong Li, Shi Zhong Liu, and Jin Qian Zhao. "Microstructures of Low Angle Boundaries of the Second Generation Single Crystal Superalloy DD6." Advanced Materials Research 284-286 (July 2011): 1584–87. http://dx.doi.org/10.4028/www.scientific.net/amr.284-286.1584.

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The specimens of low angle boundaries were machined from the second generation single crystal superalloy DD6 blades. The microstructures of low angle boundaries (LAB) were investigated from three scales of dendrite, γ′ phase and atom with optical microscopy (OM), scanning electron microscope (SEM), transition electron microscope (TEM) and high resolution transmission electrion microscopy (HREM). The results showed that on the dendrite scale LAB is interdendrite district formed by three dimensional curved face between the adjacent dendrites. On the γ′ phase scale LAB is composed by a thin layer γ phase and its bilateral imperfect cube γ′ phase. On the atom scale LAB is made up of dislocations within several atom thickness.

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Irfan, H., K. Mohamed Racik, and S. Anand. "X-ray peak profile analysis of CoAl2O4 nanoparticles by Williamson-Hall and size-strain plot methods." Modern Electronic Materials 4, no. 1 (May 1, 2018): 31–40. http://dx.doi.org/10.3897/j.moem.4.1.33272.

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CoAl2O4nanoparticles were prepared by a sol-gel process using citric acid as chelating agent with different calcination temperatures of 600 to 900 °C. The crystalline spinel cubic phase was confirmed by X-ray diffraction results. High-resolution scanning electron microscopy (HRSEM) revealed that nanoparticles of CoAl2O4morphology showed spherical forms with a certain degree of agglomeration. The Williamson-Hall (W-H) method and size-strain method to evaluate the size of crystallites and strain in the CoAl2O4nanoparticles peak broadening were applied. Physical parameters such as strain and stress values were calculated for all XRD reflection peaks corresponding to the cubic spinel phase of CoAl2O4in the range of 20 to 70° from the modified plot shape by W-H plot assuming a uniform deformation model (UDM), uniform stress deformation model (USDM), uniform deformation energy density model (UDEDM) and by the size-strain plot method (SSP). The CoAl2O4NPs crystal size calculated on the W-H plots and the SSP method are in good agreement with the HRSEM Scherrer method.

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CHEN, H., X. K. LU, S. Q. ZHOU, X. H. HAO, and Z. X. WANG. "FABRICATION AND CHARACTERISTICS OF ALN NANOWIRES." Modern Physics Letters B 15, no. 30 (December 30, 2001): 1455–58. http://dx.doi.org/10.1142/s0217984901003068.

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Single phase AlN nanowires are fabricated by a sublimation method. They were characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), typical selected area electron diffraction (SAED) and high-resolution transmission electron microscopy (HRTEM). The SEM and TEM images show that most of the nanowires have diameters of about 10–60 nm. The crystal structure of AlN nanowires revealed by XRD, SAED and HRTEM shows the AlN nanowires have a wurtzite structure.

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Xie, Juan, Wei Zhao, Li Bian, Ru Bin Feng, and Yan Xie. "Influence of External Factors on Anisotropic Growth Habit of ZnO Crystal." Advanced Materials Research 148-149 (October 2010): 1440–43. http://dx.doi.org/10.4028/www.scientific.net/amr.148-149.1440.

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Monodispersed ZnO micro/nanocrystals with various morphologies were successfully prepared via a simple solution route at low temperature. The products were characterized by means of scanning electron microscopy (SEM), X-ray diffraction (XRD), high-resolution transmission electron microscope (HRTEM), and selected area electron diffraction (SAED). Results suggest a close relationship between the morphology of ZnO and the external factors. Possible mechanisms for the controllable synthesis of ZnO particles are preliminarily discussed.

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van Benthem, Klaus, Christina Scheu, Wilfried Sigle, Christian Elsässer, and Manfred Rühle. "Electronic Structure Investigations of Metal / SrtiO3 Interfaces Using EELS." Microscopy and Microanalysis 7, S2 (August 2001): 304–5. http://dx.doi.org/10.1017/s1431927600027598.

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Ni, Pd and Cr thin films were grown on (100)SrTiO3 surfaces by molecular beam epitaxy at substrate temperatures of TNJ, pd=650°C and Tcr =150°C. Electron energy-loss spectroscopy (EELS) and high resolution transmission electron microscopy (HRTEM) were applied to investigate the local electronic structure and the atomic structure of the interfaces, respectively. Analytical microscopy was carried out with a parallel energy-loss spectrometer (PEELS766) attached to a dedicated scanning transmission electron microscope (STEM) operated at 100keV, which has a point resolution of 0.22 nm. HRTEM studies were performed on a Jeol JEM ARM 1250 operated at 1250keV (0.12 nm point resolution). Conventional TEM and HRTEM experiments showed epitaxial orientation relationships between the thin metal films and the substrate for each interface.The electronic structure of the interfaces in terms of the site- and symmetry projected density of states (PDOS) above the Fermi-level can be extracted from the electron energy-loss near-edge structures (ELNES).

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Mariappan, R., V. Ponnuswamy, P. Jayamurugan, R. N. Jayaprakash, and R. Suresh. "Structural, Optical and Electrical Properties of Thin Films Using Nebulizer Spray Pyrolysis Technique." Indian Journal of Materials Science 2013 (November 24, 2013): 1–8. http://dx.doi.org/10.1155/2013/516812.

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thin films have been deposited on glass substrates at substrate temperature 400°C through nebulizer spray pyrolysis technique. X-ray diffraction (XRD) analysis shows that the films structure is changed from hexagonal to tetragonal. The high-resolution scanning electron microscopy (HRSEM) studies reveal that the substrate is well covered with a number of grains indicating compact morphology with an average grain size 50–79 nm. Energy dispersive X-ray analysis (EDAX) reveals the average ratio of the atomic percentage. Optical transmittance study shows the presence of direct transition. Band gap energy decreases from 3.33 to 2.87 eV with respect to the rise of Sn content. The electrical resistivity of the thin films was found to be 106 Ω-m.

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Fischione, P. E., J. Ringnalda, Y. Feng, T. Krekels, H. O. Colijn, M. J. Mills, and J. M. Wiezorek. "The Use of a Cold Gas Plasma for the Final Processing of Contamination-Free TEM Specimens." Microscopy and Microanalysis 3, S2 (August 1997): 985–86. http://dx.doi.org/10.1017/s1431927600011818.

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The issue of specimen contamination becomes more important at a rate proportional to the use of high-brightness electron source Transmission Electron Microscopes (TEM). These TEMs combine smaller electron probes with increased current, allowing high resolution specimen imaging and enhanced analytical data collection. Small, high current electron probes tend to increase the detrimental effect of hydrocarbon presence on the specimen's surface. The subsequent formation of carbon deposits caused by the focused probe often times obstructs imaging and precludes acceptable analytical results. by plasma cleaning the specimen, contamination is removed and the results obtained by high resolution electron microscopy (HREM), scanning transmission electron microscopy (STEM) and analytical electron microscopy (AEM) using EDS or electron energy loss spectroscopy (EELS) are greatly enhanced. Recent instrumentation developments have resulted in the application of a high frequency, low energy, reactive gas plasma generated in an oil-free vacuum that chemically removes hydrocarbon contamination from both the TEM specimen holder and the specimen without altering its properties.

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Zhang, Hai Dong, Yu Shen, and Xu Xu Zheng. "Synthesis of Mesoporous Silica Nanotube Bundles." Advanced Materials Research 233-235 (May 2011): 2375–78. http://dx.doi.org/10.4028/www.scientific.net/amr.233-235.2375.

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Mesoporous silica nanotube bundles with short channels were synthesized through a surfactant-templated process with the addition of dodecane. Transmission electron microscope (TEM) and high resolution scanning electron microscope (HRSEM) studies show that the channels of the silica nanotubes are parallel gathered in nano-size bundles. Each particle of these nano-size bundles contains less than 10 silica nanotubes. The length of the silica nanotube channel is about 200 nm while the pore size of the channels is about 11 nm. Dodecane solubilized in the hydrophobic cores of P123 micelles leads to large pore size and the unique bundle structure of the silica nanotubes.

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Journal articles on the topic 'High Resolution Scanning Electron Microscopy (HRSEM)'

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