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Here surprising results are shown demonstrating a workflow possibly able to exploit the discreet nature of interactions between high-energy electron beams and matter. Isolated protein constructs have been imaged after an original temperature-curing in vacuum, introduced recently for flash-frozen rigid biopolymers, and here applied to flash-frozen oligomers of viral origin. These results, if confirmed, may extend to plastics and bio-oligomers the access to atomic coordinates in one experimental session, when imaged by electron microscopy. Which is the case when imaging semiconductors or other solid materials, provided that the samples are not damaged by the interaction with accelerated electron beams in vacuum. Therefore, potentially, this workflow introduces the possibility of achieving atomic resolution in only one experiment with data only about one individual protein, maybe out of thermodynamic equilibrium. Such data are vital to understand protein-protein interactions. Finally, this workflow offers the possibility, new to cryo-electron microscopy samples, to store a sample indefinitely under liquid nitrogen for imaging the same molecules in more than one experimental session.

We report on formation of epi-layer of SixGe1-x by taking standard procedure in CMOS technology. The competitive process of solid solubility of Ge dopant into Si and SiO2 is the key to engineer atomically sharp, low defect very thin epitaxial layer at the interface of oxide-Si. Oxidation time process was used to control the distribution of the doped Ge ions at the interface of Si with oxide and in the oxide layer. Implanted samples (35 keV and 1 × 1016 Ge+/cm2) were oxidized at 1050 °C for 30–90 min. RBS-Channeling analysis shows two separate peaks of Ge corresponds to different depths after oxidation. Corroborate with high resolution microscopy and elemental analysis, we determined the first peak as enriched layer of SixGe1-x at the interface of SiO2single bondSi. Less than 10 nm epitaxially grown interfacial layer is very low in defects, and Ge ions are fully substituted into the host lattice. The second peak originated from diffusion of Ge into SiO2 resulted in a segregated layer containing Ge in oxide film. Technological demand on forming SixGe1-x layer for CMOS application through standard routes is what we address in this research. published

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.

This paper presents an advanced microstructural analysis of the AlSiMg, Ti64 and N700 powders used for additive manufacturing. The internal microstructure of the regular and irregular powder grains were characterized down to atomic resolution by using scanning electron microscopy and high resolution scanning transmission electron microscopy.The accretionary forms on top of the irregular AlSiMg powder grains exhibit a slightly coarse microstructure with a network of eutectic Si consisting of nano-crystallites, suggestinga slower cooling than the grain itself that contain a predominately amorphous Si network. A nm thin amorphous C layer on the surface of some Ti64 plasma atomized powder grains promoted the attachment of satellites and growth of envelopes. In case of gas atomized N700 powder grains, we identified thin oxide and carbon amorphous layers as well as metal segregations at the interface between the grain body and the accretionary forms.

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.

Starting from subsurface Zr0-doped “inverse” Pd and bulk-intermetallic Pd0Zr0 model catalyst precursors, we investigated the dry reforming reaction of methane (DRM) using synchrotron-based near ambient pressure in-situ X-ray photoelectron spectroscopy (NAP-XPS), in-situ X-ray diffraction and catalytic testing in an ultrahigh-vacuum-compatible recirculating batch reactor cell. Both intermetallic precursors develop a Pd0–ZrO2 phase boundary under realistic DRM conditions, whereby the oxidative segregation of ZrO2 from bulk intermetallic PdxZry leads to a highly active composite layer of carbide-modified Pd0 metal nanoparticles in contact with tetragonal ZrO2. This active state exhibits reaction rates exceeding those of a conventional supported Pd–ZrO2 reference catalyst and its high activity is unambiguously linked to the fast conversion of the highly reactive carbidic/dissolved C-species inside Pd0 toward CO at the Pd/ZrO2 phase boundary, which serves the role of providing efficient CO2 activation sites. In contrast, the near-surface intermetallic precursor decomposes toward ZrO2 islands at the surface of a quasi-infinite Pd0 metal bulk. Strongly delayed Pd carbide accumulation and thus carbon resegregation under reaction conditions leads to a much less active interfacial ZrO2–Pd0 state. ISSN:2073-4344

During wear, materials undergo chemical and mechanical changes that lead to the formation of what are known as ‘third bodies’. Tribologists have long understood that third bodies have significant influence on the friction and wear performance of materials. However, the inhomogeneous nature of third bodies and how they form at the ‘buried interface’ of a sliding tribological contact has long made it difficult to fully characterize and study them. Recently, there have been significant advancements in nanomechanical testing such that researchers have begun to use these techniques to, for the first time, determine mechanical properties of third bodies. Coupling these measurements with high resolution electron microscopy and surface chemical analysis has finally given tribologists the ability to obtain the necessary data to understand and model third bodies and their connections to friction and wear. This review will present recent work on the topic of nanomechanical testing of third bodies while at the same time identifying the challenges and opportunities this research presents.

A model alloy Fe-20Cr-0.5Si (wt.%) exposed to Ar-20CO2 and Ar-20CO2-20H2O at 818 °C formed a duplex scale of an outer Cr2O3 layer and an inner SiO2 layer in both gases. Water vapour promoted formation of fine Cr2O3 grains and additional Cr2O3 blades. The blades were discovered by high resolution electron microscopy to be bicrystals, containing an internal interface, available as a fast diffusion path for chromium. Different blade cross-section shapes are accounted for by the competition between blade lengthening and thickening, the latter supported by vapour phase deposition.

The professional and private lives of Wolfgang Baumeister, Sir Colin Humphreys, John C.H. Spence and Knut Urban are retraced on the occasion of their 80th (Humphreys, Urban) and 75th (Baumeister, Spence) birthdays

Shellac is a biocompatible resin of natural origin, comprising a mixture of polyesters and single esters, commonly used as a protective coating in the food and pharmaceutical industries. Remarkably, the physicochemical characteristics of shellac, in particular its excellent film forming, low vapor permeability, and good adhesion properties, are very untypical to low molecular weight materials. This study was aimed at exploring the nanostructure of shellac and gaining insights into the structure-property relations alongside the effect of its aging phenomena. Small angle x-ray scattering and high resolution electron microscopy experiments revealed a unique bicontinuous nanostructure in shellac. Using manipulations of shellac’s composition and studies of shellac solutions in ethanol, we could identify the hydrophilic phase, the lipophilic phase, and the amphiphile residing on the interface between them. The bicontinuous morphology, typified by an extremely large interfacial area, was used to explain shellac’s physicochemical characteristics and mechanical properties. Although significant effort has been devoted to generating and stabilizing bicontinuous molecular organization in man-made systems, it is surprising to discover that the conditions required for this unique morphology exist in native shellac. Understanding this exceptional morphology may open the way for further manipulation that will enable better control over shellac’s properties and its utilization for novel applications, such as a coating material in drug or pesticide delivery systems.

Alloy 600 (Ni-16Cr-9Fe) and Alloy 800 (Fe-35Ni-23Cr) were exposed to simulated primary water at 315 °C. Oxidation phenomena were studied using high resolution electron microscopy. Extensive intergranular oxidation was observed in Alloy 600. In Alloy 800, only shallow intergranular oxygen penetration was detected. The mechanism of intergranular embrittlement in Alloy 600 is likely analogous to internal oxidation. Internal oxidation may not apply to Alloy 800 due to the formation of external rather than internal oxides. Comparisons are made to previous experiments in high temperature hydrogenated steam to validate the latter’s use as an accelerated primary water simulant environment.

Transition metal dichalcogenides (TMDs) are a class of two-dimensional (2D) materials that have attracted growing interest because of their unique electronic and optical properties. Under ambient conditions, most TMDs generally exhibit 2H or 1T structures. Unlike other group VIb TMDs, bulk crystals and powders of WTe2 exist in a distorted 1T structure (Td) at room temperature and have semimetallic properties. There is so far a lack of direct atom-by-atom visualization, limiting our understanding of this distorted 2D layered material system. We present herein atomic resolution images of Td structured WTe2. The Td structure can be distinguished in the three major orientations along the [100], [010], and [001] zone axes. Subtle structural distortions are detected by atomic resolution imaging, which match well with the optimized structure relaxed by ab initio calculations. The calculations also showed that both crystal field splitting and charge density wave (CDW) interactions contribute to the stabilization ...

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.

This work presents the use of high resolution electron microscopy (HREM) and geometric phase analysis (GPA) to measure the interplanar spacing and strain distribution of three gold nanomaterials, respectively. The results showed that the {111} strain was smaller than the {002} strain for any kind of gold materials at the condition of same measuring method. The 0.65% of {111} strain in gold film measured by HREM (0.26% measured by GPA) was smaller than the {111} strains in two gold particles. The presence of lattice strain was interpreted according to the growth mechanism of metallic thin film. It is deduced that the {111} interplanar spacing of the gold thin film is suitable for high magnification calibration of transmission electron microscopy (TEM) and the gold film is potential to be a new calibration standard of TEM.

The single crystal of Al2O3/Y3Al5O12 eutectic was prepared by an optical floating zone furnace. The microstructure evolution during directional solidification was studied by electron backscattered diffraction, and orientation relationship of the two phases in SX was characterized by high resolution electron microscopy. Competitive growth of the Al2O3/Y3Al5O12 grains was observed. Single crystal Al2O3 was obtained in a shorter growth distance than Y3Al5O12 during solidification. The competitive growth behavior was discussed and misfit between the two phases was calculated.

Starting from subsurface Zr0-doped “inverse” Pd and bulk-intermetallic Pd0Zr0 model catalyst precursors, we investigated the dry reforming reaction of methane (DRM) using synchrotron-based near ambient pressure in-situ X-ray photoelectron spectroscopy (NAP-XPS), in-situ X-ray diffraction and catalytic testing in an ultrahigh-vacuum-compatible recirculating batch reactor cell. Both intermetallic precursors develop a Pd0–ZrO2 phase boundary under realistic DRM conditions, whereby the oxidative segregation of ZrO2 from bulk intermetallic PdxZry leads to a highly active composite layer of carbide-modified Pd0 metal nanoparticles in contact with tetragonal ZrO2. This active state exhibits reaction rates exceeding those of a conventional supported Pd–ZrO2 reference catalyst and its high activity is unambiguously linked to the fast conversion of the highly reactive carbidic/dissolved C-species inside Pd0 toward CO at the Pd/ZrO2 phase boundary, which serves the role of providing efficient CO2 activation sites. In contrast, the near-surface intermetallic precursor decomposes toward ZrO2 islands at the surface of a quasi-infinite Pd0 metal bulk. Strongly delayed Pd carbide accumulation and thus carbon resegregation under reaction conditions leads to a much less active interfacial ZrO2–Pd0 state.

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 paper brings new information about the superstructure present in the monoclinic A2/m BiLuWO6 crystal phase. Electron diffraction (ED) and high resolution electron microscopy (HREM) investigations in several crystal projections have highlighted the presence of cationic vacancies ordered in the fluorite and perovskite blocks. The order generates a doubling of the unit-cell parameter b and a lowering of the translation symmetries inside the lattice in agreement with the P2 space group (SG).

An investigation of Al–12.7Si–0.7Mg alloy aged at 160 °C, 180 °C and 200 °C for 3 h was carried out in order to identify the precipitating phases. Regular transmission and high resolution electron microscopy (TEM and HREM) were employed for this purpose. The studies were focused on the dark spots and needle-shaped precipitates lying in (001)Al plane. Based on the HREM observations, dark spots and needle-shaped precipitates have different characteristics. The results revealed that the ellipsoidal and needle-shaped precipitates along direction of the matrix coexist in the alloy by tilting experiments at given aging condition. The ellipsoidal dark spot precipitates viewing along [001]Al is not cross-sectional image of needle-shaped precipitates along Al. Needle-shaped precipitate is coherent with the matrix. The diffraction pattern associated with the ellipsoidal precipitates is consistent with β″ reported in literature.

Phase pure SnS nanosheets were synthesized by a hot injection method from a new single molecular precursor (SMP), dibutyl-bis(piperidinedithiocarbamato)tin(IV) in oleylamine at 230 °C. The tin complex was characterized by single crystal X-ray crystallography, nuclear magnetic resonance, thermogravimetry and microelemental analysis. The complex is thermally stable up to 260 °C, after which it decomposes in a single step with a major mass loss between 260 °C and 300 °C. The thermolysis of the as-prepared precursor was carried out in oleylamine between 190 and 230 °C. The formation and shape evolution of SnS was investigated using high resolution electron microscopy. The mechanism of the time dependent growth of SnS from spherical particles into nanosheets is proposed.

Although the size effect in ferroelectric thin films has been known for long time, the underlying mechanism is not yet fully understood and whether or not there is a critical thickness below which the ferroelectricity vanishes is still under debate. Here, we directly measure the thickness-dependent polarization in ultrathin PbZr0.2Ti0.8O3 films via quantitative annular bright field imaging. We find that the polarization is significantly suppressed for films, Understanding ferroelectricity at reduced dimensions will be important for future sub-nanoscale devices based on ferroelectrics. Using high resolution electron microscopy; Gao et al., observe the existence of a measurable polarization at a thickness of just 1.5-unit cells

To integrate materials with large lattice mismatch as GaAs on silicon (Si) substrate, one possible approach, to improve the GaAs crystalline quality, is to use nanowires (NWs) technology. In the present contribution, NWs are grown on 〈111〉 oriented Si substrates by molecular beam epitaxy (MBE) using vapor-liquid-solid (VLS) method. Transmission electron microscopy (TEM) analyses show that NWs are mainly grown alternating wurtzite and zinc blend (ZB) phases, and only few are purely ZB. On the latter, High Resolution Electron Microscopy (HREM) evidences the presence of twins near the surface of the NW showing limited concordance with the calculations of Yuan (2013) [1], where {111} twin planes in a 〈111〉-oriented GaAs NW attain attractive interactions mediated by surface strain. In addition, such twins allow slight strain relaxation and are probably induced by the local huge elastic strain observed by HREM in the lattice between the twin and the surface. The latter is attributed to some slight bending of the NW as shown by the inversion of the strain from one side to the other side of the NW.

The results of using HRTEM to study the real structure of low-dimensional systems at the atomic level, obtained in Institute of Semiconductor Physics of Siberian Branch of Russian Academy Science (ISP SB RAS) for the last decades, are the main content of the present contribution. Besides, the main potentials and a brief description of the HRTEM method, and the methodic base for investigating and analyzing the atomic structure of low-dimensional semiconductor systems are considered in the first informational part of the work.

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.

Catalytic systems designated for preferential oxidation of CO in the presence of H2 are prepared by ball milling of Cu and CeO2, a simple and cheap one-step process to synthesize such catalysts. It is found that after 60 min of milling, a mixture of 8 wt.% Cu–CeO2 powders exhibits CO conversion of 96% and CO selectivity of about 65% at 438 K. Two active oxygen states, which are not observed in case of pure CeO2, were detected in the nanocomposite lattice and attributed to the presence of Cu in surface sites as well as in subsurface bulk sites. Correspondingly, oxidation of CO to CO2 was found to occur in a two-stage process with Tmax ≈ 395/460 K, and oxidation of H2 to H2O likewise in a two-stage process with Tmax ≈ 465/490 K. The milled powder consists of CeO2 crystallites sized 8–10 nm agglomerated to somewhat larger aggregates, with Cu dispersed on the surface of the CeO2 crystallites, and to a lesser extent present as Cu2O. [Figure not available: see fulltext.] © 2016, Springer Science+Business Media Dordrecht.

In this paper, high resolution electron microscopy (HREM) was used to observe nanosized Fe2M precipitates in M50NiL steel, and crystal structure of which was also investigated by selected area electron diffraction (SAED). At the same time, the orientation relationship between the Fe2M and the martensite matrix was also studied. The results suggested that crystal structure of Fe2M is close-packed hexagonal, and lattice parameters about a=b=0.473nm, c=0.772nm, α=β=90°, γ=120°. The orientation relationship between the nanoprecipitates Fe2M and martensite is and .

We report on a specific defect, which may form during the growth of Stranski-Krastanov surfactant-mediated Ge/Si (100) islands. Transmission electron microscopy reveals that these loop-like defects are local and could be represented by a missing plane of Ge atoms inside some of Ge islands. This specific defect may generate an electrically active trap within the Si band gap at about 0.3 eV above the Si valence band edge. Deep level transient spectroscopy reveals that at least 1 % of Ge islands may include such defects.

High-resolution electron microscopy is an efficient tool for characterizing heterogeneous nanostructures; however, currently the analysis is a laborious and time-consuming manual process. In order to be able to accurately and robustly quantify heterostructures, one must obtain a statistically high number of micrographs showing images of the appropriate sub-structures. The second step of analysis is usually the application of digital image processing techniques in order to extract meaningful structural descriptors from the acquired images. In this paper it will be shown that by applying on-line image processing and basic machine vision algorithms, it is possible to fully automate the image acquisition step; therefore, the number of acquired images in a given time can be increased drastically without the need for additional human labor. The proposed automation technique works by computing fields of structural descriptors in situ and thus outputs sets of the desired structural descriptors in real-time. The merits of the method are demonstrated by using combustion-generated black carbon samples.

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.

We report on the results of analysis of the superdispersed product synthesized in a superfast jet of electric-discharge carbon plasma flowing to the nitrogen atmosphere. The data obtained by high resolution transmission electron microscopy indicate the presence of the α phase of hypothetic carbon nitride C3N4 in the form of unique quasi-two-dimensional multilayer particles.

High-resolution transmission electron microscopy and first-principles energy calculations reveal that, upon formation, the hardening precipitates in Cu–Ni–Si alloys are unchanged δ-Ni2Si nanocrystals. However, their crystallographic and morphological features evolve during the precipitation process. It is shown that, in terms of crystallographic orientation relationships, there are basically two types of δ-Ni2Si precipitates in the alloys, referred to as δ1-Ni2Si and δ2-Ni2Si respectively. In the early stages of aging (including peak aging), the precipitates are small and belong to the δ1 type, with the following orientation relationship with the Cu matrix: [0 1 0]δ||[1 1 0]Cu and (0 0 1)δ||(0 0 1)Cu. In the late stages, the precipitates are clearly larger and become the δ2 type, with the orientation relationship: [0 1 0]δ||[1 1 0]Cu and approximately ( 3 0 1 ) δ ‖ ( 1 1 ¯ 1 ) Cu . Governed by the minimization of its overall energy, a developing δ precipitate has to evolve from an almond-like δ1 particle with a low-index coherent habit plane to a French baguette bread-slice-shaped δ2 particle that has a high-index broad interface. This evolution is found to be in excellent agreement with predictions provided by the invariant line theory. Intermediate stages exist for a particle to accomplish such an evolution, leading to many different crystallographic and morphological appearances of these δ-Ni2Si particles being observed in the alloys.

Morphological and surface characteristics of γ-Al2O3 are topics of high relevance in the field of catalysis. Using tomography and high-resolution transmission electron microscopy (TEM) imaging, we have studied the surface characteristics of a model γ-Al2O3 synthesized in the shape of platelets and macroscopically defined by (110)Al2O3 and (111)Al2O3 surface facets. We show that the dominant (110)Al2O3 surface of the synthesized γ-Al2O3 is not atomically flat but undergoes a significant reconstruction, forming nanoscale (111)Al2O3 facets. In addition to high-resolution imaging, tomographic analysis was carried out, enabling an examination of the pores/voids, which were found to be mostly enclosed within the bulk and inaccessible to gases or solvents carrying precursors for metal particles. Tomographic analysis shows that the surfaces of the pores are defined exclusively by (100)Al2O3 and (111)Al2O3 facets. The importance of these findings is discussed in the context of relative surface energies of low inde...

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.

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.