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The intensities and phase profiles of the elliptic optics vortex beam both are determined by the topological charge (TC) and ellipticity. This paper presents an efficient and simple method for measuring the TC and ellipticity of elliptic vortex. By observing the diffraction patterns, the TC modulus and ellipticity can be probed with the suitable rectangular aperture, and the TC sign can be detected with the suitable right triangular aperture. The scheme works well even for high-order elliptic vortex with topological charge value as high as ± 18, and ellipticity range from 0.5 to 2 at least. Obviously, the measurement of TC and ellipticity have important research value for promoting the application of elliptical vortex.

The version of this article on this repository is an arXiv preprint (arXiv:2208.14575v2 [physics.ins-det] Mon, 6 Mar 2023 19:46:42 UTC (39,794 KB)) submitted to Elsevier and is not the final, peer reviewed, corrected article. It is made available under a Creative Commons (CC BY 4.0) Attribution License. This article presents a collection of simulation studies using the ECCE detector concept in the context of the EIC's exclusive, diffractive, and tagging physics program, which aims to further explore the rich quark–gluon structure of nucleons and nuclei. To successfully execute the program, ECCE proposed to utilize the detector system close to the beamline to ensure exclusivity and tag ion beam/fragments for a particular reaction of interest. Preliminary studies confirm the proposed technology and design satisfy the requirements. The projected physics impact results are based on the projected detector performance from the simulation at 10 or 100 fb−1 of integrated luminosity. Additionally, insights related to a potential second EIC detector are documented, which could serve as a guidepost for future development. Office of Nuclear Physics in the Office of Science in the Department of Energy, the National Science Foundation, USA, the Los Alamos National Laboratory Directed Research and Development (LDRD), USA 20200022DR, the Natural Sciences and Engineering Research Council of Canada (NSERC), and the UK Research and Innovation Science and Technology Facilities Council; This research used resources from the Compute and Data Environment for Science (CADES) at the Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC05-00OR22725; Brookhaven National Lab and the Thomas Jefferson National Accelerator Facility which are operated under contracts DE-SC0012704 and DE-AC05-06OR23177 respectively.

Graphical abstract, Highlights • The mappings between micro cracks and diffraction pattern curves were revealed based on GIXD and MD. • Surface and subsurface defects of CaF2 crystals induced by abrasive machining were evaluated and characterized accurately. • MD simulated results agreed well with the experimental results. • This work provided a novel technology for nondestructive testing of defects of single crystals at nano- and micro- scales., Introduction Surface and subsurface defects were easily induced during abrasive machining process of optical crystals due to their high brittleness. Accurate characterization of these defects is the prerequisite for obtaining optical components with high surface integrity. Objectives This work aims to evaluate subsurface defects of CaF2 single crystals induced by abrasive machining, the mappings between micro cracks and diffraction pattern curves, and the influence of micro cracks on lattice structures. Methods Molecular dynamics simulation, grazing incidence X-ray diffraction experiments and cross-sectional TEM detection were used in this work. Results In grazing incidence X-ray diffraction (GIXD) detection experiments on lapping and polished specimens, shifts phenomenon of the peak position under the non-theoretical grazing incidence angle indicated that the subsurface was damaged to a certain extent. The micro cracks of the subsurface were evaluated by the consistent characteristic of “peak drift” of the diffraction pattern curve in both experiments and simulations. In addition, cross-sectional TEM results showed that regular micro cracks were found on the subsurface, which agreed well with the simulation results. Conclusion The subsurface defects of CaF2 single crystals induced by abrasive machining, and the influence of micro cracks on lattice structures can be evaluated by molecular dynamics simulation. The simulation results revealed the mappings between the micro cracks and diffraction pattern curve, which demonstrated that a phenomenon of “peak drift” occurred near the diffraction angle of a specific crystal plane. This work provided a novel technology for the nondestructive testing of defects of single crystal materials at nano- and micro- scales.

Structured illumination microscopy (SIM) is a fluorescence light microscopy method that relies on modulation of the excitation light by spatial patterning to break the diffraction barrier. SIM provides a resolution gain of only a factor of two, yet has the least stringent requirement for fluorophores selection and readily accommodates multiple color labeling. These properties make SIM the method of choice in super-resolution microscopy when imaging several structures simultaneously and with high-throughput, due to its flexibility and relative ease of sample optimization. In this article, we provide an introduction to the principles of SIM, detail its impact in cell biology, and present the most recent developments of this imaging technology.

Crystallographic twins are critical to the properties of numerous materials from magnesium alloys to piezoelectrics. Since the onset of the twin formation is highly sensitive to the triaxial mechanical boundary conditions, non-destructive bulk microscopy techniques are required. Elastic strains can be mapped via X-ray diffraction with a 100-200 nm resolution. However, the interplay of strains with nanotwins cannot be characterized. Here, a method based on dark-field X-ray microscopy to quantify the density of nanotwin variants with twin lamellae of sizes as small as several tens of nanometers in embedded subvolumes (70x200x600 nm3) in millimeter-sized samples is introduced. The methodology is corroborated by correlating the local density of twin variants to the long-ranging strain fields for a high-performance piezoelectric material. The method facilitates direct, in situ mapping and quantification of nanoscale structural changes together with their elastic driving fields, which is the key towards controlling and engineering material's performance at nanometric scales.

CrFeCoNi and CrMnFeCoNi coatings were prepared using laser remelting technology. The microstructure and phase composition of coatings were investigated. X-ray diffraction (XRD) results indicated that CrFeCoNi and CrMnFeCoNi coatings presented face-centered cubic structure. Electrochemical measurements were used to reveal the corrosion behavior of coatings. Results showed that CrFeCoNi coating exhibited lower corrosion current density, lower passive current density and higher charge transfer resistance than CrMnFeCoNi coating in H2SO4 solution (0.5 mol/L). This indicated that CrFeCoNi coating possessed higher corrosion resistance. Mott-Schottky analysis revealed that the passive film formed in CrFeCoNi coating possessed lower donor density value in contrast with that of CrMnFeCoNi coating, suggesting that CrFeCoNi coating formed a more protective passive film. The corrosion mechanisms of coatings were also revealed.

The quest for miniaturization of devices and control over surface properties motivate rigorous efforts to artificially fabricate surfaces with nanometer features. Here we present a method for fabricating curved, meandering grooves with submicrometer spacing by laser irradiation in liquid. We show that this is possible by using the cavitation bubbles formed during irradiation as diffraction objects to spatially modulate the intensity distribution of the beam, which is imprinted into the top layer of material surface. The bubbles are manipulated with thermo-optical tweezers by thermocapillary forces generated by the temperature gradient in the liquid around the irradiation spot. The presented results show that high viscosity of the liquid, producing laminar flow conditions, provides sufficient stability of the cavitation bubble dynamics for the generation of regular arc-shaped concentric microgroove channels with a depth of several hundred nanometers and a radius of curvature in the micrometer range. Their position is determined by the beam guiding pattern. The results clearly show that cavitation bubbles can be used as an aid in laser ablation in liquids and not just as an undesirable effect, as usually classified in the literature.

In the present work, a general and simple approach to determine texture patterns using pole figure was developed. For the rolled materials, the rolling plane can be determined by the ratio of OP/R in the given pole figure. Here, OP is the length from the center to an arbitrary pole in the pole figure, and R is the radius of the projection circle in the pole figure. Rolling direction for the rolled materials or the extrusion direction for the extruded materials can be directly calculated using the coordinate values of the poles in the given pole figure. For cubic and hexagonal materials, the calculated results using the developed approach are in agreement with the standard stereographic projection pole figures. The textures in the rolled and annealed Fe–17Cr ferritic stainless steel and extruded Mg–2Mn alloy were examined by electron backscatter diffraction and X-ray diffraction. The proposed approach was applied to determine texture patterns in the above two materials. It was found that {111} type of γ-fiber texture develops for the as-annealed Fe–17Cr ferritic stainless steel and + double fiber texture develops for the extruded Mg–2Mn alloy.

The solid state reaction method was used to synthesise the Li2MnSiO4 ceramic. The first principle calculation, X-ray diffraction, scanning electron microscopy, network analysis, and differentia-thermal analysis were taken to analyse its sintering and dielectric properties. The TE-mode Cylindrical Cavity method based on a cavity resonator was conducted to obtain the dielectric property at different frequencies. Two phases were formed, namely, Li2SiO3 and LiMn2O4, and the increasing sintering temperature increases the amount of LiMn2O4 and decreases that of Li2SiO3. The peak dielectric properties were obtained at 1000 °C; er = 7.99 at 9.2 GHz, 7.86 at 10.6 GHz and 7.8 at 14.2 GHz; and tanδ = 0.00375 at 9.2 GHz, 0.00387 at 10.6 GHz and 0.004 at 14.2 GHz. The bulk density is 3.44 g/cm3, and the relative density is 96.1%.

The oxidation behaviors of type 444 ferritic stainless steel (FSS) were studied in air and synthetic exhaust gas at 1000, 1050 and 1100 oC, respectively, by means of mass gain, X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS). The oxidation rate of 444 FSS enlarges in both environments with the increase of temperature, but is faster in synthetic exhaust gas than in air under isothermal conditions. The oxidation rate becomes very fast since the occurrence of breakaway transition. Both the higher temperature and the synthetic exhaust gas facilitate the breakaway oxidation. The breakaway oxidation results mainly from the growth of oxide nodules and the spallation of oxide scale. The synthetic exhaust gas isn’t conducive to the formation of SiO2 layer in comparison with the air. The oxidation mechanisms are discussed on the basis of the oxide scale characteristics.

In the present paper we report proof of consistent non monotonic lattice variation (NMLV) as a function of grain size in nanocrystalline CeO2. By analyzing more than 30 powder samples of CeO2 with grain size ranging from 5 to 200 nm which were synthesized by three different methods, it was found that in the nanocrystalline powders the unit cell parameters are smoothly varying along the decreasing of grain size with moderate contraction between 100 to 30 nm and severe expansion when the grain size become smaller than 20 nm. As a result of these two opposite trends a minimum value of unit cell parameter was detected in grain size between 25 to 50 nm. The lattice parameter change can be modeled as two global effects acting simultaneously. The first one is a contraction due to surface tension and the second one is a lattice expansion caused by ionic bonds weakening as the grain size decreases. This model can be applied to most ionic nanocrystalline materials. Consequently, it is recommended to add a new category “ambient-nano” in the crystallographic and diffraction data bases for nanomaterials with structures controlled by grain size.

Graded structures with different architectures were obtained by spark plasma sintering from (Ba1-xSrx)TiO3 (BST, x = 0.10; 0.20; 0.30) powders. The presence of the composition gradient was confirmed by structural and compositional investigations using X-ray diffraction and electron microscopy combined with energy dispersive X-ray spectroscopy. The concentration gradient was either asymmetric (3 layers, starting with x = 0.10 and ending with x = 0.30) or symmetric (5 or 6 layers, starting and ending with x = 0.10, and with a single or double x = 0.30 layer in the middle, respectively). Electrical measurements reveal a decrease of the dielectric constant with increasing the number of the layers. It was found that the symmetric graded structure with 6 layers has the best thermal stability of both, the dielectric constant (variation of only 8% between zero and 100 °C) and the pyroelectric coefficient (6% variation between zero and 80 °C). In addition, an enhancement of the pyroelectric signal for frequencies above 100 Hz is obtained in symmetric structures, an effect that is attributed to the additive contributions of the signals originated from the layers with different Sr content.

This paper describes a study exploring milling and subsequent heat treatments of pure IrO2 and Ta2O5 powders. Reactants were milled under Ar atmosphere in a SPEX 8000D mill, with structural, morphological, and compositional characterizations (during milling and after subsequent heat treatments) by X-ray diffraction, energy-dispersive spectroscopy, and transmission electron microscopy. Electrochemical stability of powders was evaluated by open circuit potential (OCP). Results showed that the mechanical energy transferred during this process induces a reaction between IrO2 and Ta2O5, forming metallic Ir and Ir(Ta)O2 saturated solid solution. The study additionally shows that this reaction can be thermally induced with previous mechanical activation of reactants. Electrochemical evaluations of milled powders immersed in H2SO4 solution revealed that OCP shifts negatively with increasing milling time, approaching that of pure Ir at 15 h milling. Resumen: Este trabajo describe la molienda y subsecuente tratamiento térmico de polvos de IrO2 y Ta2O5. Los reactantes fueron molidos bajo atmósfera de Ar en un molino SPEX 8000D. Los polvos fueron caracterizados mediante difracción de rayos X, espectroscopía de energía dispersiva de rayos X y microscopia electrónica de transmisión. La estabilidad electroquímica fue evaluada mediante potencial de circuito abierto. Los resultados obtenidos mostraron que la energía mecánica transferida durante el proceso de molienda induce la reacción entre el IrO2 y Ta2O5, formando Ir metálico y una solución sólida saturada Ir(Ta)O2. Adicionalmente, se demostró que esta reacción puede ser térmicamente inducida posterior a una activación mecánica de los reactantes. La evaluación electroquímica de los polvos inmersos en una solución de H2SO4, reveló que a medida que el tiempo de molienda aumenta, el potencial de circuito abierto disminuye, hasta alcanzar el potencial presentado por el Ir puro luego de las 15 h de molienda.

Additive manufacturing (AM) alternative technologies, including Fused Filament Fabrication (FFF), offer the possibility to produce both prototypes and low-volume production metallic components. This is the first time that AISI M2 high-speed steel powder is processed by FFF, achieving near full density in a complementary way to Powder Injection moulding (PIM), yet reducing the investment cost and the lead time. A completely optimized FFF process is presented: from the design of a printable highly filled metallic filament that can be fed into conventional 3D printers, to high-quality green parts that are properly debound and sintered. The final specimens (99.6% densified) are thermally treated (one quenching and two tempering) and, then, evaluated in terms of scanning electron microscopy (SEM), X-ray diffraction (XRD) analysis and mechanical characterization (hardness and wear resistance). The effect of the processing technology and the heat treatments are discussed, validating the feasibility of FFF to develop customized high-speed tools with superb performance at a competitive cost.

Core‒rim structures were identified as a common feature in hot-pressed ZrB2 ‒SiC‒MC ceramics (M = Nb, Hf, Ta and W) by a combination of X-ray diffraction, scanning and transmission electron microscopies. Quantitative analyses associate them with the bi-solubility of M in ZrB2 phase, in which transition of solubility across the core/rim boundary is abrupted, signifying their creation via dissolution‒reprecipitation process facilitated by transient liquid-phase. The cores were retained from starting powder after surface melting and the rims were grown from the liquid-phase to incorporate more solutes, leaving the residual liquid to turn into ZrC phase with higher solubility of M. We propose g-point scheme in the ZrB2‒MB2 diagrams to combine the bi-solubility and the core‒rim structures into an intra-phase relationship created by sintering, leading further to a hierarchical phase relationship. The temperature dependence of flexural strength in the ZrB2 ‒SiC‒MC ceramics varies with MC additions, which can be respectively strengthened by the strain energy created in the core‒rim structures and metal segregation to grain boundaries.

MAX phases exhibit excellent combination of ceramic and metallic-like properties. In this work, MAX phase Ti3SiC2 powder was synthesized starting-off with different combinations of elemental powders and carbides. The powders used were Ti, Si, C, SiC and TiC in different combinations, molar ratios and powder size. Powders were heat treated on a vacuum furnace for different times and temperatures for in situ production of the Ti3SiC2 MAX phase. High purity synthesized samples were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM) in order to identify and quantify the different phase constituents present. The main phase constituents in the powders produced were Ti3SiC2 and TiSi2. Up to 94% of Ti3SiC2 MAX phase was obtained using Ti:SiC:C as starting powders in a molar ratio of 3:1.5:0.5. Different phase constitution was observed on the surface and the centre of the samples. An optimal starting powder composition, molar ratio, heat treatment temperature and time is proposed for the formation of high purity Ti3SiC2 MAX phase. Selected mixture was studied thermodynamically and a reaction mechanism of formation of the MAX phase is proposed. Las fases MAX presentan una excelente combinación de propiedades cerámicas y metálicas. En este trabajo se sintetizaron polvos de fase MAX Ti3SiC2 a partir de diferentes combinaciones de polvos elementales y carburos. Los polvos utilizados fueron Ti, Si, C, SiC y TiC en diferentes combinaciones, proporciones molares y tamaño de partícula. Los polvos se sinterizaron en un horno de vacío a diferentes tiempos y temperaturas para la producción in situ de la fase MAX Ti3SiC2. Las muestras sintetizadas de alta pureza se analizaron mediante difracción de rayos X (XRD) y microscopía electrónica de barrido (SEM) para identificar y cuantificar las diferentes fases constituyentes presentes. Las principales fases constituyentes en los polvos producidos fueron de Ti3SiC2 y TiSi2. Se obtuvo hasta un 94% de fase MAX Ti3SiC2 utilizando como polvos de partida Ti:SiC:C en una proporción molar de 3:1,5:0,5. Se observó diferente formación de fase en la superficie y en el centro de las muestras. Finalmente, se propone una composición óptima de polvo de partida, relación molar, temperatura de sinterización y tiempo para la formación de la fase MAX de Ti3SiC2 de alta pureza. La mezcla seleccionada se estudió termodinámicamente y se propone un mecanismo de reacción para la formación de la fase MAX. The authors would like to thank the funding provided for this research by the Regional Government of Madrid (Dir. Gral. Universidades e Investigación) through the project P2018/NMT4411 (ADITIMAT-CM), the Spanish Government through the Ramón y Cajal contract RYC-2014-15014 and the project MAT2012-38650-C02-01.

TiN granular thin films were deposited on SiO2 substrates using cathodic cage plasma nitriding (CCPN) and SEM images, roughness analysis, contact angle measurements, and X-ray diffraction (XRD) were employed to characterize the structure of these films varying time and temperature of the process. Results have shown an inverse relationship between roughness and contact angle. Thin films with low roughness have presented higher contact angle values, and the opposite was observed in the films with more prominent or more grains per area. TiN is a hydrophobic material, and the decrease of contact angle value presented in some films produced occur due to modification of the morphological characteristics, which the roughness measurements and hysteresis of contact angle confirmed it, specifically, for samples synthesized at 2h and 350°C, the roughness is the smallest, and the contact angle is the largest [(111.23±8.87)°]. This connection between roughness and contact angle is essential, and it can be used to describe and characterize the most types of thin films produced by plasma deposition and to infer the surface modifications with different atmospheres of treatment.

The objective of the present study is to investigate the effect of ageing heat treatment condition on the structural characteristics and corrosion protection performance of the passive layers forming on the surface of age hardened Al 6061 alloy using X-ray diffraction, Mott-Schottky, point defect model and potentiodynamic polarization techniques. The results showed that n-type semi-conductive passive layers are formed on the surface of age hardened samples; creation of more lattice microstrain in the alloy (as a result of age hardening process) leads to the formation of passive layers including less crystal defects giving them less passive current density values. Moreover, the point defect model results showed that crystal defects will diffuse at higher rates through more defective passive layers giving the age hardened alloy less resistance to the pitting corrosion.

Magnesium oxide (MgO) and Zinc oxide (ZnO) nanoparticles (NPs) have been successfully synthesized by solid–solid reaction method. The structural properties of ZnO and MgO NPs were studied using X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD results indicated a formation of pure MgO and ZnO NPs. The mean diameter values of the agglomerated particles were around to be 70 and 50 nm for MgO and ZnO NPs, respectively using SEM analysis. Further, a wide-range of nuclear radiation shielding investigation for gamma-ray and fast neutrons have been studied for Magnesium oxide (MgO) and Zinc oxide (ZnO) samples. FLUKA and Microshield codes have been employed for the determination of mass attenuation coefficients (μm) and transmission factors (TF) of Magnesium oxide (MgO) and Zinc oxide (ZnO) samples. The calculated values for mass attenuation coefficients (μm) were utilized to determine other vital shielding properties against gamma-ray radiation. Moreover, the results showed that Zinc oxide (ZnO) nanoparticles with the lowest diameter value as 50 nm had a satisfactory capacity in nuclear radiation shielding. © 2020 Korean Nuclear Society

In reactive-hot-pressed ZrB2–SiC–ZrC ceramics, ZrO2 was found to replace ZrC phase, hence leading to confusion in designing ultra-high-temperature ceramics (UHTCs). We employ high-precision X-ray diffraction and electron microscopies to reassess the phase behavior during entire reaction and densification and to reveal the evolution of multiphase relationship at different stages before reaching the final ZrB2–SiC–ZrO2 composition. Frozen from transient liquid-phase, bulk glassy phase of 15 vol% was found to be constituted of Zr–Si–B–C–O with stable Zr:O ratio, which starts as early as in the intermediate stage to suppress ZrC in favor of SiC nucleation. Inhomogeneity in phase relations and microstructures results from variation in local transient liquid-phase to develop SiC phase in various modes and rates. As inferred from the earlier report of phase formation, competing reactions for ZrC and ZrB2 phases in the initial stage below 1000 °C were mediated via Zr–O–B–C liquid phase. Such liquid phase was moderated by stable B–O components, as initiated from surface oxides of starting powders. This picture under a continuous mother liquid phase can unify the reactions and sintering into a collective melting–nucleation–growth process, which enables and guides the evolution of multiphase relationship through several stages to reach final densification at relatively low temperature with the help of residual oxides.

A computer-aided methodology for the approximate prediction of axially textured polycrystals’ properties is presented. The input data for the developed application consist of: (a) the two-dimensional diffraction pattern of the material under investigation and (b) the tensors of the elasto-piezo-dielectric properties of the single crystal case. Program ANAELU 2.0 allows the determination of the fiber axis inverse pole figure by means of a Rietveld-type procedure. The Material Properties Open Database (MPOD, http://mpod.cimav.edu.mx) provides free access to the experimentally determined values of the tensor properties for several crystal species. Practical estimates of polycrystals’ properties may be obtained by averaging single crystals’ properties tensors, with the orientation distribution function (the symmetry-axis inverse pole figure, in fiber textures) as a weight factor. This treatment, with the application of the Voigt, Reuss and Hill approaches, requires special precautions when it comes to the coupling properties (e.g. piezoelectricity, magnetostriction, magnetoelectricity). Some key physical, mathematical and computational aspects related to the considered topic are discussed. Program GISELLE systematizes the calculation of polycrystal properties under the considered treatments. The application of the proposed methodology to real-world events is illustrated by means of a case study. Resumen: Se presenta una metodología asistida por computadora para la predicción aproximada de las propiedades de policristales con textura axial. Los datos de entrada para la aplicación desarrollada consisten en: a) el patrón de difracción bidimensional del material bajo investigación y b) los tensores de las propiedades elasto-piezo-dieléctricas para el caso del monocristal. El programa ANAELU 2.0 permite determinar la figura inversa de polos del eje de la fibra mediante un procedimiento de tipo Rietveld. La base de datos de propiedades de los materiales Material Properties Open Database (MPOD, http://mpod.cimav.edu.mx) proporciona acceso gratuito a los valores experimentales de las propiedades tensoriales de numerosas especies monocristalinas. Una metodología de valor práctico para el pronóstico aproximado de las propiedades de policristales texturados consiste en promediar los tensores de las propiedades de los cristales individuales, con la función de distribución de orientaciones (la figura inversa de polos del eje de simetría, en texturas de fibra) como factor de peso. Este tratamiento, con la aplicación de los enfoques de Voigt, Reuss y Hill, requiere de precauciones especiales cuando se trata de las llamadas propiedades de acoplamiento (por ejemplo, piezoelectricidad, magnetostricción, magnetoelectricidad). Se discuten algunos aspectos clave (físicos, matemáticos y computacionales) relacionados con el tema considerado. El programa GISELLE sistematiza el cálculo de las propiedades del policristal bajo los tratamientos considerados. Se muestra la aplicación de la metodología propuesta a un caso ilustrativo.

This work focuses on the changes of raw hydroxyapatite obtained from porcine bones during heat treatment with heating rates of 2.5 and 5.0 °C/min between 600 °C and 1100 °C. High-Resolution transmission electron microscopy (HR-TEM) images showed that raw hydroxyapatite was formed by high-ordered nanometric platelet crystals with a length of around 18 nm and width around 7 nm. High-Resolution scanning electron microscopy (HR-SEM) images evidenced the coalescence phenomena during heating giving. It was found that the growth of the crystals and the transition from nano to a micro-size occurred at around 700 °C. And the changes in the full width at half maximum (FWHM) for the characteristic (002) plane of the X-ray diffraction patterns and the FWHM of the characteristic Raman band at 960 cm-1 for ν1 PO43- exhibited the transition from nano to a micro size, that was confirmed by HR-SEM images and the thermogravimetric (TG) analysis. The porosity of the BIO-HAp changes from intra nanometric to intercrystalline.

Perovskite single crystals have the potential to design a new path in optoelectronics. Due to the toxicity and stability issue of lead halide perovskites, the substitution of lead is a challenge. Here, we have demonstrated two different single crystal growth mechanisms namely slow cooling and anti-solvent vapor diffusion method for lead-free Cs3Bi2Cl9 perovskite single crystal and exhibited how these different growth methods affect the symmetry parameters and morphology evolution of single crystal structure. The synthesis, crystal growth, and detailed structural and thermal characterization have been carried out by optical and electron microscopy, elemental mapping, single crystal X-ray diffraction, and thermogravimetric analysis. Our study shows that contrary to the conventional expectation the crystal symmetry, Patterson vector, and Sheldrick's criterion is different for the same single crystal stoichiometry with two different crystal growth methods. The calculated metric tensor in real and reciprocal space is different for two different growth mechanisms. Our study opens up a personalized design strategy for choosing a suitable single crystal fabrication route among various available strategies for specific non-linear optical or optoelectronic applications.

The behavior of potassium chloride (KCl) as a main mud shale inhibitor remains poorly defined in the interlayer of montmorillonite (Mt). In this paper, a new analysis method of transmission electron microscopy-energy dispersive X-ray spectroscopy (TEM-EDS) was established. The distribution of K+ in the interlayer of Mt and the processes surrounding d-spacing shifts in Mt were investigated through X-ray diffraction and TEM-EDS. The experimental results revealed shoulder peaks in the diffraction patterns at KCl concentrations between 11% and 19%. The distribution of K+ varied in the inner and outer layers of Mt with different KCl concentrations. It could be concluded that the distribution of K+ and the changes in d-spacing of Na are determined by two factors: negative charge sites and concentration difference. When the KCl concentration was below 8%, both factors cause the outer layer of Mt to adsorb more K+ than the inner layer, with all layers exhibiting d-spacings within the 1.50 nm state. At an 8% KCl concentration, all negative charge sites were occupied by K+. As the KCl concentration rose above 8%, the outer layer of Mt adsorbed more K+ than the inner layer due to the concentration difference. With a further increase in the KCl concentration, the d-spacing shifted linearly to 1.30 nm from the outer to the inner layer of Mt. All layers of Mt exhibited a d-spacing of 1.30 nm at KCl concentrations of up to 23%. These results demonstrate the benefits and capabilities of the proposed method in investigating the intercalating mechanisms of Mt.

In this study, high-energy ball milling processes were adopted to prepare Fe/Fe2–3N composites. The phase composition and microstructure of the composites were characterized by X-ray diffraction, scanning electron microscopy and high-resolution transmission electron microscopy. The composites were nanostructured by high-energy ball milling containing lots of interfaces, grain boundaries and defects in its particle. The magnetic property and electromagnetic parameters were identified by vibration sample magnetometer and vector network analyzer. The saturation magnetization value is 174.65 emu/g. The electromagnetic absorption performance was simulated by transmission line theory. The composites have effective electromagnetic wave absorption over the whole Ku band (12.4–18 GHz). The optimal reflection loss value reached −32.4 dB at 12.4 GHz. The mechanisms of the composites absorbing electromagnetic wave had been discussed.

A novel approach of improving the antibacterial rate by tailoring matrix texture was investigated in 2.0 wt%Cu-bearing Fe-17Cr alloy through different rolling processes. Demonstrated by X-ray diffraction (XRD), the main orientation relationship between the copper precipitation and matrix is Kurdjumov–Sachs (K–S) relationship of {111}Cu//{110}Fe, Cu//Fe. Because of being elongated along Matrix directions, the rod-shaped copper precipitation in the matrix grain with {110} crystal plane is parallel to the rolling plane and has a maximum area exposed to the outside environment. The crystallographic orientations in the hot-rolled sample are equally distributed and there is no very focused and intense orientation. However, there are very strong components on the γ-fiber ({111}⊥ND texture) and Goss texture in the cold-rolled sample. Thus, the effective exposed area of copper precipitation in the cold-rolled sample is larger than that in the hot-rolled sample. Because the strong γ-fiber is beneficial to improve the corrosion resistance property, the cold-rolled sample has a better corrosion resistance and the copper ions are more easily released from the cold-rolled sample compared with the hot-rolled sample. Hence, the γ-fiber ({111}⊥ND texture) and Goss texture can improve the antibacterial rate obviously.

Conventional SEM-based micro-texture technique has attracted broad interests in recent years. There is also an important need to develop TEM based micro-texture methods, since it was expected to back up some of the shortages of conventional micro-texture technique. In the present work, a new methodology was proposed for measuring the micro-texture in TEM manually without the assistance of any external commercial attachment. The orientation matrix, which maps uniquely to the Euler angles, was considered the transformation matrix between crystal coordinates and the sample coordinate. By tilting the TEM specimen to a low-index zone axis with a double-tilt sample holder, the crystal coordinates could be drawn based on the acquired diffraction pattern. The transformation matrix between each defined coordinates could be deduced; and the Euler angles were identified accordingly. The micro-texture of a twin lamella in a rolled magnesium sheet was analyzed as an example.