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Misfit-layered compounds (MLCs) are formed by the combination of different lattices and exhibit intriguing structural and morphological characteristics. MLC SrxLa1-xS-TaS2 nanotubes with varying Sr composition (10, 20, 40, and 60 Sr atom %, corresponding to x = 0.1, 0.2, 0.4 and 0.6, respectively) were prepared in the present study and systematically investigated using a combination of high-resolution electron microscopy and spectroscopy. These studies enable detailed insight into the structural aspects of these phases to be gained at the atomic scale. The addition of Sr had a significant impact on the formation of the nanotubes with higher Sr content, leading to a decrease in the yield of the nanotubes. This trend can be attributed to the reduced charge transfer between the rare earth/S unit (LaxSr1-xS) and the TaS2 layer in the MLC which destabilizes the MLC lattice. The influence of varying the Sr content in the nanotubes was systematically studied using Raman spectroscopy. Density functional theory calculations were carried out to support the experimental observations. © 2019 Serra et al. Center for Nanoscale Science and Technology, CNST: 43535000350000, 720821 Government Council on Grants, Russian Federation: NORTE-45-2015-02 Israel Science Foundation, ISF: 7130970101 We acknowledge the support of the Israel Science Foundation (grant No. 7130970101). We also wish to acknowledge the Perlman Family Foundation, the Kimmel Center for Nanoscale Science Grant No. 43535000350000, and the Irving and Azelle Waltcher Foundations in honor of Prof. M. Levy Grant No. 720821. The activity of A.E. was supported by Act 211 Government of the Russian Federation, contract No.02.A03.21.0006. E.A.A and F.L.D acknowledge the financial support by the N2020: Nanotechnology based functional solutions (NORTE-45-2015-02).

The implantation-induced defects of crystalline silicon implanted with helium ions to a dose of 5 × 1016/cm2 at 600 °C were investigated. The sample was analyzed by transmission electron microscopy and high-resolution electron microscopy. Faceted cavities are observed in the damaged layer. Concurrently the distribution of interstitial-type defect clusters was investigated by conventional electron microscopy in bright and dark field. Many rod-like defects, which belong to {1 1 3}, {1 1 1} and (−2 0 0), are formed in the end of the projected range. In front of the damaged layer, some ribbon-like defects are formed, which belong to 〈2 0 0〉, 〈1 −1 1〉 and 〈1 3 −3〉. The possible reasons of the observed defect clusters are discussed.

The recent advances in liquid-phase transmission electron microscopy represent tremendous potential in many different fields and exciting new opportunities. However, achieving both high-resolution imaging and operando capabilities remain a significant challenge. This work suggests a novel in situ imaging platform of liquid-flowing graphene chip TEM (LFGC-TEM) equipped with graphene viewing windows and a liquid exchange system. The LFGCs are robust under high-pressure gradients and rapid liquid circulation in ranges covering the experimental conditions accessible with conventional thick SiNx chips. LFGC-TEM provides atomic resolution for colloidal nanoparticles and molecular-level information limits for unstained wet biomolecules and cells that are comparable to the resolutions achievable with solid-phase and cryogenic TEM, respectively. This imaging platform can provide an opportunity for live imaging of biological phenomena that is not yet achieved using any current methods.

This work presents our recent findings that a small addition (0.5 at. %) of Cr to FeCo–2V alloy leads to a great improvement in creep resistance. High resolution electron microscopy was applied to study microstructural evolution of the Cr added alloy during the creep process performed at 600 °C under 200 MPa. At an initial step of the creep, there appear plate-like precipitates with bcc/fcc structure as well as some rod-like ones with hcp structure. A coherent relationship is identified between the precipitates and bcc FeCo matrix. With prolonging the creep, the rod-like hcp precipitates are revealed to remain in the bcc matrix, showing a good stability under the creep condition and in turn resulting in piling-up of dislocations to a great extent around the precipitates. In addition, the Cr added alloy is shown to have a large stress exponent of 8.4, indicating a strong interaction between dislocations and the hcp precipitates.

We report on the design, fabrication and optical performance of gain mirrors in single crystal diamond substrates for vertical external cavity surface emitting lasers (VECSELs). VECSELs have gained attention recently due to their potential for high emission power in single mode with low beam divergence, yet their maximum output power remains typically limited due to thermal roll-over resulting from insufficient heat dissipation. In order to increase the heat transfer, we exploit the excellent thermal conductivity of single crystal diamond, which is assembled in direct contact with the active structure. The optical cavity is hereby defined by an output coupler and a high reflection grating structure etched into the diamond surface. We here present the design and microfabrication of a diffraction grating that was optimized to reflect light into the 0th order, therefore combining the role of a gain mirror and a heatsink at the same time. Our process involved metal mask deposition onto the diamond surface, e-beam lithography and reactive ion etching. Characterization showed reflection above 95% at a center wavelength of 1550 nm, potentially allowing the integration of the diamond mirror into a vertical external cavity surface emitting laser.

The field ion microscope-atom probe and high resolution electron microscope have been used to study a rapidly solidified AlCr alloy. The material, containing 6.9–9.0 wt.% Cr, was produced by vapour deposition. In the as-deposited state, chromium-rich rod- or disc-shaped zones were found. The zones were about 5 nm in length, about 0.2–1.3 nm in width, parallel to {111} planes and along directions. In addition, a preliminary heat treatment was conducted. It was found that the zones remain relatively stable after annealing at 623 K for 15 min.

Carbon extracted from a cathodic graphite rod following arc-discharge in helium is examined using high-resolution electron microscopy. It is found that, in addition to the well known extended graphitic tubules ('buckytubes'), carbon produced in this way contains many other novel graphitic structures. Of particular interest are small hollow particles which, although essentially tubular, appear to differ in significant ways from the extended tubules. Evidence for tetrahedral bonding in some of the graphitic particles is also presented.

High-resolution electron microscopy is used to study the structure of two typical non-graphitizing carbons before and after heat treatment at temperatures in the range 2100–2600°C. It is found that these heat treatments can result in the formation of closed carbon nanoparticles, which are apparently fullerene-like in structure. This suggests that fullerene-like elements were present in the original carbons and leads us to propose a new model for the structure of non-graphitizing carbons.

Aberration-corrected electron microscopes currently dominate the high-resolution scene but they are not the only instruments that can provide such information. Other techniques are attracting attention, notably ptychography and the use of phase plates. Moreover, operation of these aberration-corrected microscopes at their ultimate performance raises questions that are still under discussion. We note too that correctors can be useful for tasks other than correction, such as vortex beam creation. To conclude, the specialized role of electron mirrors is recalled.

Experiments on absorption of TmCl3 and Tm(NO3)3 from dry acetonitrile and aqueous solutions, respectively, were performed using carboxylated multiwalled carbon nanotubes with conic and cylindrical displacement of graphene layers. Using HAADF TEM imaging and EDX spectroscopy it was found that in the first case the chemisorption with complex compound formation with oxygen from carboxylated MWCNTs takes place while in the later this process is hampered by kinetic factor and side reactions with water. The data obtained are in good agreement with results of thermal-mass spectral and elemental CHNSO analysis. This particularity allows using transmission electron microscopy and related techniques for direct surveying of light atoms-containing groups on the surface of carbon materials. In the case of carboxylated cylindrical and conic MWCNTs it demonstrate that nanotubes in the second case are uniformly covered by functional groups while in the first – near the ends of tubes and the local defects along the surface.

As reported in our previous works, a Mg-7Gd-5Y-1Nd-0.5Zr alloy recently developed exhibited remarkable age-hardening responses and excellent mechanical properties at both room and elevated temperatures. In Mg-7Gd-5Y-1Nd-0.5Zr alloy, the β precipitate phase was assumed to be one of the main strengthening phases in peak-aged samples. This study aimed to determine the crystal structure and orientation relationship of the β precipitate phase in Mg-7Gd-5Y-1Nd-0.5Zr alloy using transmission electron microscopy and high-resolution electron microscopy. The results indicated that the β precipitate had a face-centered cubic structure with a lattice parameter of a=2.22 nm. The orientation relationship between the β precipitate phase and the α-Mg matrix was ( 1 ¯ 12 ) β / / ( 1 ¯ 100 ) α , [ 110 ] β / [ 0001 ] α . The β plates formed on prismatic planes could play an important role in alloy strengthening by proving effective barriers to gliding dislocations. A single β plate often contained several domains of ( 1 1 ¯ 1 ) β twin-related variants. A composition of Mg5(Y0.4Gd0.4Nd0.2) was suggested for the β phase in Mg-7Gd-5Y-1Nd-0.5Zr alloy.

Twin boundary (TB) and twinning dislocations (TDs) in { 10 1 ¯ 1 } twins in deformed polycrystalline cobalt (Co) were studied by high-resolution electron microscopy. The { 10 1 ¯ 1 } TB tends to be flat and a mirror plane. The observed TD was characterized directly from the experimental image by the circuit-mapping method and predicted by the topological model. The observed TD with a localized core can stably exist in { 10 1 ¯ 1 } twins in Co.

On the landscape of the nanoscience and nanothecnology carbon nanotubes (1) have played an important role on the development of 1D materials. They consist of single (SWCNT) or multi (MWCNT) layers of graphene cylinders arranged around a central hollow. In the case of the SWCNT the size distribution is narrow (1-2 nm) while it is broader for MWCNT (2-25 nm) exhibiting a constant separation between layers, nearly equal to that of graphite-layer spacing (0.34 nm). In both cases, the length extends up to several microns. These characteristics provide large external and internal surfaces making both functionalization and filling processes very attractive for potential performances in several areas like electronic, spintronic, or drug release

High-resolution electron microscopy was applied to analyze the continuous precipitated particles of the γ-Mg 17 Al 12 phase with Pitsch-Schrader OR in the heat-treated AZ91 alloy at 473 K for 8 h. The existence of a continuous precipitated particle with the Pitsch-Schrader OR including the selection of the habit plane and the growth direction in Mg–Al system is rationalized by the constrained coincidence site lattice/constrained complete pattern shift lattice (CCSL/CDSCL) model and the O-lattice theory.

In this paper we demonstrate filling of carbon nanotubes (CNTs) grown by chemical vapor deposition (CVD) directly on Si 3 N 4 TEM grids. The CNTs are synthesized at different growth temperatures T CVD providing different numbers of sidewalls and diameters. We characterize each step of the peapod synthesis and focus on the opening of as-grown CNTs, which is necessary for filling them with guest molecules like C 60 . Thus, the creation of defects during peapod synthesis and the resulting peapods are studied using high resolution TEM and Raman spectroscopy.

In the present work, transmission electron microscopy (TEM) techniques were used in order to study the morphology and investigate the structural properties of a (BixSb1-x)2Te3(BST) thin film. The sample was fabricated on silicon substrate by pulsed laser deposition (PLD) method. Towards this aim, cross sectional and planar view samples were prepared, suitable for High Resolution Electron Microscopy. Results revealed a polycrystalline, c-axis oriented film with coherent boundaries between neighboring columnar grains. © Springer International Publishing Switzerland 2015. 164 3 7 3-7

Correlative microscopy combines the advantages of both light and electron microscopy to enable imaging of rare and transient events at high resolution. Performing correlative microscopy in complex and bulky samples such as an entire living organism is a time-consuming and error-prone task. Here, we investigate correlative methods that rely on the use of artificial and endogenous structural features of the sample as reference points for correlating intravital fluorescence microscopy and electron microscopy. To investigate tumor cell behavior in vivo with ultrastructural accuracy, a reliable approach is needed to retrieve single tumor cells imaged deep within the tissue. For this purpose, fluorescently labeled tumor cells were subcutaneously injected into a mouse ear and imaged using two-photon-excitation microscopy. Using near-infrared branding, the position of the imaged area within the sample was labeled at the skin level, allowing for its precise recollection. Following sample preparation for electron microscopy, concerted usage of the artificial branding and anatomical landmarks enables targeting and approaching the cells of interest while serial sectioning through the specimen. We describe here three procedures showing how three-dimensional (3D) mapping of structural features in the tissue can be exploited to accurately correlate between the two imaging modalities, without having to rely on the use of artificially introduced markers of the region of interest. The methods employed here facilitate the link between intravital and nanoscale imaging of invasive tumor cells, enabling correlating function to structure in the study of tumor invasion and metastasis.

Polycrystalline Sr3CaMn2CoO9 and (Sr0.5Ca0.5)15Mn7Co4O33 have been synthesized and characterised by X-ray and electron diffraction, high resolution electron microscopy and magnetic measurements. These oxides constitute the α = 3, β = 1 and α = 4, β = 1 terms of the homologous series (A3B2O6)α(A3B3O9)β, respectively. Isolated rows of polyhedra sharing faces along the c-axis are made up of units of two and one face-sharing octahedra (occupied by Mn) linked by one trigonal prism (occupied by Co) in an ordered way. The chains are separated by columns of Sr/Ca atoms. Magnetic measurements suggest antiferromagnetic correlations in the two new commensurate monodimensional oxides. The influence of the size of alkaline-earth atoms on the long-range magnetic interactions is discussed.

High-resolution electron microscopy is employed to observe the atomic arrangement of very tip of the growing martensite plate and that of the growing bainite. Transition lattice region with a certain dimension (more than a few nm), of which the structure is neither fcc nor bcc, but an intermediate one between fcc and bcc lattice, is found in martensite but not in bainite. Because of this fact, it is concluded that the martensitic transformation is of the shear-type transformation and the bainitic transformation is of the diffusion-type transformation.

The infinite layer compound Ca0.85Sr0.15CuO 2 has been synthesized by the sol-gel technique using the acetate gel route. The compound is found to be single-phasic as evidenced from the powder X-ray and electron diffraction measurements. EDAX analysis confirms the presence of homogenous stoichiometric phase pertaining to the composition Ca 0.85Sr0.15CuO2. High-resolution electron microscopy (HREM) studies reveal interesting defects in the infinite layer frame work of the system. Apart from the usual strain and shear induced defects observed in the lattice, which is common among the perovskite compounds, the main finding is the defect along [0 1 0], occurring due to the intercalation of extra AO layer in the CuO2 plane. Such a defect is accommodated in the lattice by the increase in the interplanar distance (which is basically the c-axis parameter) from 3.2 to 3.4 � in the defective layer. This implies the formation of square pyramidal oxygen co-ordination of copper at the defect site. ? 2005 Elsevier Ltd. All rights reserved.

An YNi2B2C thin film grown on a MgO(001) substrate by pulsed laser deposition has been investigated by transmission electron microscopy (TEM) and high-resolution electron microscopy (HREM). Plan-vi...

Boron nitride (BN) nanohorns with various tip angles were synthesized by an arc-melting method, and atomic structure models for BN nanohorns were proposed from high-resolution electron microscopy. Stability and electronic structures of the BN nanohorns were investigated by molecular orbital/mechanics calculations, which indicated that multi-walled BN nanohorns would be stabilized by stacking of BN nanohorns. The energy gaps of the BN nanohorns were calculated to be 0.20∼0.85 eV, which are lower compared to those of BN clusters and nanotubes.

Electron diffraction and high resolution electron microscopy have been used to characterize two new one-dimensional superstructures in the A Rh O system (A = Ca, Sr) related to the 2H-ABO3-type. They are formed by the intergrowth of n A3A′BO6 blocks, showing the Sr4RhO6-type, with A12A′2B8O30 blocks, constituted by two A3O9 and two A3A′O6 layers alternating in the stacking sequence 1:1, leading to the A27A′7B13O60 ( n = 5 ) and A30A′8B14O66 ( n = 6 ) compositions. A crystallographic shear mechanism is proposed to describe the structural relationship between Sr4RhO6 (A3A′BO6-type) and the new superstructures.

The core structures of perfect 60 and edge dislocations in diamond are investigated atomistically in a density-functional based tight-binding approach, and their dissociation is discussed both in terms of structure and energy. Furthermore, high resolution electron microscopy is performed on dislocation cores in high-temperature, high-pressure annealed natural brown diamond, and HRTEM image simulation allows a comparison of theoretically predicted and experimentally observed structures.

High-resolution electron microscopy is used to study interfaces between solids with varying degree of atomic ordering. Applying a recently developed technique the structure of amorphous germanium near (111) oriented crystalline silicon is described by its two-dimensional distribution function ρ(x,y) of atoms, and properties of ρ(x,y) are extracted from experimental images. Using extensive image simulations it is further shown that the technique is suitable to measure composition profiles at coherent heterointerfaces.

The structures and components of different pigments from the Feng Hui tomb situated in Bin County, Shaanxi Province, dated in the Five Dynasties (907–960 AD), were analyzed by Raman spectroscopy and high-resolution electron microscopy (HREM). It is shown that the red, yellow and black samples are cinnabar, PbSO4–PbO and carbon black, respectively, and well preserved, which provide scientific data for later conservation. Moreover, the results indicate that HREM and Raman analysis are very effective for identifying ancient inorganic pigments at low concentrations. Copyright © 2004 John Wiley & Sons, Ltd.

Growth of Ni on (001) Au has been widely studied. Furthermore it has been shown that a structural change occurs when an Au/Ni multilayer is heated up. This transformation can be described as an ordering which is unexpected from the equilibrium phase diagram. A high-resolution electron microscopy study of the transformation of a coherent Au/Ni multilayer is presented in this paper. The transformation has been characterized by in-situ HREM and by extensive image processings made on both simulated and experimental images.

High-resolution electron microscopy, mass spectrometry and molecular mechanics/orbital calculations of the boron nitride-based clusters showed the formation of B 36 N 36 and Y@B 36 N 36 . Image simulations of these clusters confirmed the proposed structure model.

We report a pattern recognition approach to detect the atomic structure in high-resolution transmission electron microscopy images of graphene. The approach provides quantitative information such as carbon-carbon bond lengths and bond length variations on a global and local scale alike. © 2014 Elsevier Ltd. All rights reserved.

As shown in Chap. 5, metakaolinite shows amorphous to words X-ray and spinel too is a very weakly crystalline material. In view of it, an extremely powerful technique high resolution electron microscopy is applied for characterization.

The contact resistance of Au/Ni/p-GaN ohmic contacts for different annealing conditions was measured. This was then correlated with microstructure, including phase distribution, observed by high-resolution electron microscopy combined with energy-filtering imaging. A contact resistance of 2.22 x 10(-4) ohms cm2 for Au/Ni contacts to p-GaN after annealing at 500 degrees C for 5 min in air ambient was obtained. NiO layers were identified at the interface and upper area of annealed Ni/Au/p-GaN for air ambient. In addition, an Au layer was found at the interface of p-GaN due to a reversal reaction during annealing. Identification of the observed phases is discussed, along with possible formation mechanisms for the ohmic contacts in the Au/Ni/p-GaN system.

Crystal structures of a homologous series of Co-based layered cuprates, CoSr2(Y,Ce)sCu2O5+2s (s=1–3), have been investigated by high-resolution electron microscopy (HREM) and electron diffraction (ED) techniques. For all the three phases ED patterns showed double periodicity along a direction parallel to the CoO layers, indicating a regular alternation of two types of CoO4-tetrahedra chains within the layers. Also seen was ordering of the chains along the layer-stacking direction for the s=1 phase (Co-1212); ED patterns simulated based on the proposed superstructure model well reproduced the observed patterns. For the s=2 (Co-1222) and s=3 (Co-1232) phases in which an additional fluorite-type layer-block is inserted between two CuO2 planes, HREM and ED analysis revealed complete disorder of the CoO4 chains along the layer-stacking direction. This implies that the interlayer ordering is mainly controlled by the distance between the neighboring CoO layers.

The intermetallic phases of the binary system Al/Ni have attracted considerable effort in investigation, because of a wide field of technological applications. In our recent work we have demonstrated the influence of the microstructure on the early interreaction stages. Although the chemical and spatial information obtained by 3D-atomprobe analysis is unrivaled in resolution, identification of observed phases is only possible by use of complementary methods of investigation. The present paper describes the important role of high resolution electron microscopy for indentifying the structural nature of formed phases detected by 3D-atomprobe analysis. An outline of a model which might explain the different reaction paths in Al/Ni observed for different microstructures will be given.

A quantitative method is described for the measurememnt of displacements and strains by high-resolution electron microscopy. The image is considered to be composed of periodic sets characterized by Fourier analysis. The local amplitude and geometric phase of lattice fringes can be determined in this way. The analysis of the phase distribution leads to the determination of the local lattice configuration. The method is illustrated by different examples and its application conditions are discussed.

Atomic structures of surface and interface in (Hg,Tl,Pb)-based superconductors were investigated by high-resolution electron microscopy. The interfaces observed in Tl-based superconductors have the disordered region with ∼1 nm thickness, which would be suitable for barrier layers for tunneling junctions. Although the {001} planes of (Hg,Tl)-based oxides are fairly stable, most of the {100} planes are unstable, and atomic rearrangement was often observed. However, the HREM image of Hg 0.5 Tl 0.5 Ba 2 CuO 5 {100} showed the stable Ba–O–Ba layer at the surface, and oxygen atom positions were determined. The present study indicates that the surfaces of the Hg- and Tl-based superconductors are strongly dependent on the crystallographic planes and crystal structures.

In the field of pharmaceutical applications relying on encapsulation of drug by polymer coating, capsules based on biodegradable polymers with mean size of about 500 nm have been obtained by a patented emulsion–diffusion method. The morphology, size and structure of the nanocapsules (NC) control their pharmaceutical properties, especially release of the drug. Here is reported a decisive contribution of transmission electron microscopy (TEM) in revealing the controlled form and size of the NC: mean size values measured by TEM do agree with data obtained by laser granulometry. Moreover, the TEM magnification allows an estimation of the membrane thickness.

High-resolution electron microscopy is discussed as a measuring, rather than an imaging, technique. It is shown that the interpretation or the images could greatly benefit from a quantitative instead of a qualitative approach accompanied by quantitative statistical experimental design.

Twinning plays an important role in phase transformations and can have significant effects on microstructural evolution. Different roles of twinning in the development of microstructures during precipitation and phase transformations are reviewed and illustrated with examples from investigations by high-resolution electron microscopy, including the effect of multiple twinning on the development of Ge precipitates in Al-Ge and Ag-Ge alloys, the twin dissociation of grain boundaries in Au, the formation of hexagonal Si at twin intersections and the effect of twin boundaries on the equilibrium shape of Pb inclusions in Al.

An Al–Ni–Ru decagonal quasicrystal with 0.4 nm periodicity, which has a good long-range basic quasiperiodic order, was observed to form in rapidly solidified Al–Ni–Ru alloys. Its structure has been studied by means of high-resolution electron microscopy and high-angle annular detector dark-field techniques, and compared with that of a superlattice Al–Ni–Ru decagonal quasicrystal formed by conventional solidification. The results reveal that the rapidly solidified Al–Ni–Ru decagonal quasicrystal with 0.4 nm periodicity has a new basic structural state which is characterized by a mixture of 2 nm atomic columnar clusters with and without pentagonal symmetry.

Pd 80 Pt 20 and Pd 85 Pt 15 alloys were exposed at 673 K to a hydrogen pressure of 100 MPa for 4 h, which is called hydrogen heat treatment (HHT). After HHT the pressure composition isotherms at 273 K change remarkably and H-diffusion is enhanced. The change can be interpreted by a decomposition into a continuous Pd-rich and an embedded Pt-rich alloy. Direct evidence for this hypothesis is provided for the first time from high resolution electron microscopy. It will be shown that coherent platelets are formed after HHT which are two atomic layers thick and have an average diameter of ∼10 nm. Simulating the contrast observed in the electron microscope shows that the plates are Pt-rich.

High-resolution electron microscopy (HREM) was used to obtain information about structural variations in poly[1,6-di(N-carbazolyl)-2,4-hexadiyne) (polyDCHD) nanocrystals. Several particles in different crystallographic zones were imaged with high spatial resolution of up to 0.19nm, resulting in image information on a subunit-cell level (a = 1.74nm, b = 1.29nm and c = 0.49nm; β = 108.3°, P21/a; Z = 2). The average nanocrystal had a nominally rectangular shape and a size of about 40 nm × 80 nm with the major growth direction along the polymer chains (001). Most of the HREM images correspond to the [100] or [120] zone. In a few cases, it was also possible to image crystals oriented in the [001] zone with the polymer chain axis normal to the carbon substrate. Image interpretation was done by comparison with multislice HREM image simulations based on an approximation for the crystal structure and imaging conditions. These simulations performed for polyDCHD indicate that the HREM image is sensitive to ...

The structure of grain boundaries in rocks, which are composed mainly of fine-grained quartz and feldspar, was studied by high-resolution electron microscopy (HREM) . At most of the boundaries, not only between the same minerals but also between different minerals, lattice fringes in connected grains meet each other at interfaces with no other appreciable phases. In these boundaries, it has been found that some of the straight segments of the boundaries correspond to a low-index plane of one of the connected grains. Boundaries containing voids, with a spheroidal shape elongated along the boundaries, were observed. It is suggested that these boundaries were formed by healing of microcracks.

Two new decagonal quasi-crystals (D-phases), which have periods of 0.4 and 1.6 nm, respectively, have been found to form with different compositions in conventionally solidified Al–Ni–Ru alloys. The diffraction patterns of these two D-phases display a large number of sharp diffraction spots located at exact tenfold symmetry positions and almost no diffuse streaks, indicating that they are highly ordered quasi-crystals. The D-phase with 0.4-nm periodicity exhibits a pronounced S1-type superlattice order. The D-phase with 1.6-nm periodicity can be formed as a major phase by annealing at around 900°C. By means of high-resolution electron microscopy, the structural characteristics of the D-phase with 1.6-nm periodicity have been revealed.

Atomic displacements and interface reconstructions near a La0.9Sr0.1MnO3‐SrTiO3 interface are studied by use of the focal reconstruction technique applied in high-resolution electron microscopy. By using a quantitative model, column positions are determined with high precision (better than 0.004 nm) by least-squares minimization. A displacement vector map and interatomic distances are calculated. From these a structure model for the interface is proposed. The interface has a facetted shape, where the interatomic distance is modulated. Possible local oxygen deficiency in SrTiO3 near the interface has been observed. q 2000 Elsevier Science Ltd. All rights reserved.

Single decagonal quasicrystals of Al 70 Ni 15 Co 15 were grown by the Czochralski method at Ar atmosphere. The grown crystals were of single decagonal phase without any secondary phases due to the peritectic reaction and contained a large single quasicrystal of cm order size. The high quality and single quasicrystallinity of them were examined by the Laue transmission photography, single crystal X-ray diffraction, and high-resolution electron microscopy investigations.

The possibility of direct detection of doping atoms in the B12 cluster solid by high-resolution electron microscopy (HREM) was investigated by using calculated residual indices and difference images. The HREM images of B12-based rhombohedral boron doped with (Al, Cu) and carbon atoms were calculated at the Scherzer defocus. The difference images of Al2.6Cu1.8B105/B12 and B13C2/B12 showed Al, Cu and C atomic positions clearly at crystal thickness of 3.1 nm. Crystallographic image processing was applied to the experimental image of Al2.6Cu1.8B105, which provided the average Al and Cu atom positions. In addition, HREM images recorded from thin regions (

Keywords: Bones ; electron diffraction ; high-resolution electron microscopy ; hydroxyapatite ; image processing ; image simulation ; micro- and nanoparticles Reference CIME-ARTICLE-1999-026doi:10.1046/j.1365-2818.1999.00608.x Record created on 2007-02-15, modified on 2017-05-12