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Fusion and quality enhancement of the low-resolution Energy Dispersive X-ray Spectroscopy (EDS) maps to Scanning Electron Microscopy (SEM) panchromatic images has been proven effective by various pansharpening algorithms. The present paper aims to target the preprocessing of these maps to enhance the efficiency of the pansharpening process, with as little information loss on the chemical distribution, and as little propagated noise as possible. EDS maps present different noise intensities depending on the flatness of the surface of the analyzed object. The uneven surface maps have limited analytical value due to the noise and have not been resolution-enhanced with pansharpening due to the noise propagation limitation. In this paper, different preprocessing methods are evaluated for enabling uneven-surface particles to pansharpening: background removal, upsampling, and noise filtering. The sequence of applying preprocessing steps is analyzed. The optimal order of preprocessing steps is (i) background removal, (ii) noise filtering, and (iii) interpolation. A methodology for each of these steps is presented in the paper. The best performing pansharpening methodology is chosen to be Affinity for individual map analysis and Wavelet for multi-elemental fusion purposes. Following the methodology results in high-resolution EDS maps, even for uneven-surface particles which are, for the first time in literature, subjected to pansharpening.

When testing soft biological samples using the Atomic Force Microscopy (AFM) nanoindentation method, the force-indentation data is usually fitted to the equations provided by Hertzian mechanics. Nevertheless, a significant question remains up to date; is this a correct approach from a mathematical perspective? Biological materials are heterogeneous, so 'what do we calculate' when using a classic fitting approach? In this paper, conclusive answers to the abovementioned questions are provided. In addition, a new tool for the nanomechanical characterization of biological samples, the depth-dependent mechanical properties maps, is introduced.

We outline a public license (open source) electron microscopy platform, referred to as NanoMi. NanoMi offers a modular, flexible electron microscope platform that can be utilized for a variety of applications, such as microscopy education and development of proof-of-principle experiments, and can be used to complement an existing experimental apparatus. All components are ultra-high vacuum compatible and the electron optics elements are independent from the vacuum envelope. The individual optical components are mounted on a 127 mm (5-inch) diameter half-pipe, allowing customizing of electron optics for a variety of purposes. The target capabilities include SEM, TEM, scanning TEM (STEM), and electron diffraction (ED) at up to 50 keV incident electron energy. The intended image resolution in SEM, TEM and STEM modes is ≈ 10 nm. We describe the existing components and the interfaces among components that ensure their compatibility and interchangeability. The paper provides a resource for those who consider building or utilizing their own NanoMi.

In this paper the results of an experimental study on the behavior of aggregate shape on the compressive concrete strength was described. The main scope of that work is to answer whether there is a low-cost, low-energy methodology for predicting the behavior of an aggregate within a concrete and therefore its ultimate strength. This was achieved by using a combination of petrographic methods with GIS and MatLab software in a variety of lithologies when simultaneously producing a new micropetrographic index (Mshape) for the first time. For this reason, variable rocks such as sandstones, ultramafic, mafic and volcanic have been collected from Greece which are used as aggregates. Their petrographic characteristics as well as their geometrical properties were studied and hence their influence on concrete production. In the present study, a new micro-petrographic index is proposed based on the present proposed methodology which is able to act as a predictor of the aggregates shape and therefore of their behavior and suitability. Mshape index is strongly correlated with the geometrical indices of shape IE and IF as well as with the concrete strength.

"Thermal expansion and cold contraction" are common occurrences in nature. Resulting from "thermal expansion and cold contraction" reaction, strain effect is created, which affects the oxygen reduction reaction (ORR) activities of fuel cell catalysts. Nevertheless, the "thermal expansion and cold contraction" effects of catalysts have rarely been investigated. Herein, the influence of "thermal expansion and cold contraction" strains upon ORR activities of NiO/CoO catalysts is investigated. Experimental and first-principles calculations reveal that, when NiO/CoO are synthesized and used as catalysts under low temperature ice/water environment, there is virtually no strain effect created, and abundant active sites contribute to the good low temperature ORR activities of NiO/CoO catalysts (onset potential: 0.736 V, halfwave potential: 0.659 V). When high temperature synthesized NiO/CoO catalysts are used at low temperature, however, small amounts of active sites are created. Moreover, the adsorption activity of NiO(222) and CoO(311) stepped active sites are weakened by compressive strain of lattice contraction, which reduces their ORR activities. The "low temperature synthesis and low temperature catalysis" route proposed by this paper paves a new road for the synthesis and design of low-temperature catalysts.

Atomic Force Microscopy (AFM) nanoindentation is a powerful tool for the mechanical nano-characterization of biological samples. However, the range of Young's modulus values for the same type of samples usually varies significantly in the literature. This fact is partly related to the inhomogeneity of biological samples at the nanoscale and partly to significant mistakes during data processing. This review depicts that common errors related to (i) the real shape of the AFM tip, (ii) the range of data for which the sample presents an approximate linear elastic response, (iii) the sample's viscoelasticity, (iv) the sample's shape and (v) the substrate effects can be easily avoided without increasing the complexity of data processing. Thus, the present review paper focuses on the procedures that should be followed for the accurate processing of force-indentation curves regarding experiments on biological samples.

Electron channeling contrast imaging (ECCI) is a powerful technique to characterize the structural defects present in a sample and to obtain relevant statistics about their density. Using ECCI, such defects can only be properly visualized, if the information depth is larger than the depth at which defects reside. Furthermore, a systematic correlation of the features observed by ECCI with the defect nature, confirmed by a complementary technique, is required for defect analysis. Therefore, we present in this paper a site-specific ECCI-scanning transmission electron microscopy (STEM) inspection. Its value is illustrated by the application to a partially relaxed epitaxial Si0.7Ge0.3 on a Si substrate. All experiments including the acquisition of ECCI micrographs, the carbon marking and STEM specimen preparation by focused ion beam, and the in-situ-subsequent-STEM-in-scanning electron microscopy (SEM) characterization were executed in one SEM/FIB-based system, thus significantly improving the analysis efficiency. The ECCI information depth in Si0.7Ge0.3 has been determined through measuring stacking fault widths using different beam energies. ECCI is further utilized to localize the defects for STEM sample preparation and in-situ-subsequent-STEM-in-SEM investigation. This method provides a correlative 2.5D defect analysis from both the surface and cross-section. Using these techniques, the nature of different line-featured defects in epilayers can be classified, as illustrated by our study on Si0.7Ge0.3, which helps to better understand the formation of those detrimental defects.

Nitrate has a wide temperature range, wide operating temperature, low vapor pressure, low cost, strong heat transfer and stable chemical properties. It is widely used in solar thermal power generation heat storage material. In this paper, the alkali salt NaNO3 was modified by solution combustion method with citric acid as fuel. The structure and thermal properties of the prepared salts were studied by field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC). The results show that the solution combustion process improves the structure and thermal properties of NaNO3, and the resulting product has a new phase. The particle size and microscopic morphology of the prepared salt were changed. As the proportion of fuel increases, the hollow cuboid structure gradually grows on the surface and inside of the modified salt. The microstructure obtained is different at different ignition temperatures, and a finer and even rod-like structure is obtained at an ignition temperature of 600 °C. The specific heat capacity of all modified samples has been improved, among which solid specific heat and liquid specific heat have increased the most, respectively 3.10 J/g·K and 3.19 J/g·K, which are 140.31% and 131.16% higher than the base salt, respectively. This work not only studies the specific heat capacity of NaNO3 modified by solution combustion, but also explores the effect of micromorphology and new phase formation on its performance, which provides innovative ideas for improving the specific heat capacity of molten salt heat storage materials.