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High-energy X-ray diffraction (HE-XRD) experiments combined with an analysisbased on atomic-pair-distribution functions can be an effective tool for probing low-dimensional materials. Here, we show how such an analysis can be used to gain insightinto structural properties of PbTe nanoparticles. We interpret our HE-XRD data using anorthorhombic Pnma phase of PbTe, which is an orthorhombic distortion of the rocksalt phase.Although local crystal geometry can vary substantially with particle size at scales below 10 nm,and for very small nanoparticles the particle size itself influences X-ray diffraction patterns,our study shows that HE-XRD can provide a unique nano-characterization tool for unravelingstructural properties of nanoscale systems. Post-print / Final draft

As a prototype material of colossal barocaloric effects, neopentylglycol is investigated by combining high-precision differential scanning calorimetric measurement and high-energy x-ray diffraction measurement. The diffraction data at constant temperatures indicate a first-order phase transition with thermal hysteresis as well as the phase transition asymmetry, specifically, the phase transition is completed faster at cooling than at heating. The analysis of resulting pair distribution function confirms the intermolecular disorder in the high-temperature phase. The phase transition asymmetry is quantitatively characterized by time-resolved x-ray diffraction, which is in agreement with the thermal measurement. Also, such an asymmetry is observed to be suppressed at high pressures.

Conventionally, the radius of curvature of crystal planes in a wafer is measured by position-dependent X-ray diffraction (XRD) along a particular diagonal direction of the wafer. However, we show herein that this method is not reliable for assessing the wafer’s real three-dimensional curvature. Using commercial 2 inch 4H-SiC, GaN, AlN, and β-Ga2O3 wafers, we demonstrate that the choice of the diagonal direction along which the position-dependent XRD was acquired strongly affects not only the apparent radius of curvature but also whether it is convex or concave.

Hafnium (Hf) is an industrially important material due to its large neutron absorption cross-section and its high corrosion resistance. When subjected to high pressure, Hf phase transforms from its hexagonal close packed α-Hf phase to the hexagonal ω-Hf phase. Upon further compression, ω-Hf phase transforms to the body centered cubic β-Hf phase. In this study, the high pressure phase transformations of Hf are studied by compressing and decompressing a well-characterized Hf sample in diamond anvil cells up to 120 GPa while collecting x-ray diffraction data. The phase transformations of Hf were compared in both a He pressure transmitting medium (PTM) and no PTM over several experiments. It was found that the α-Hf to ω-Hf phase transition occurs at a higher pressure during compression and lower pressure during decompression with a helium (He) PTM compared to using no PTM. There was little difference in the ω-Hf to β-Hf phase transition pressure between the He PTM and no PTM. The equation of state was fit for all three phases of Hf and under both PTM and no-PTM.

Bis(L-serinium) oxalate dihydrate (BLSOD) crystals synthesized and structure derived from single crystal x-ray diffraction analysis and compared with early reported BLSOD. Compared to the reported structure the present structure has two new C-H…O hydrogen bonding. The hydrogen bonding interactions of O•••H (69.6%), H•••H (24%), C•••H (2.7%), C•••O (1.6%) and 0•••0 (2.1%), are derived from the Hirshfeld surface analysis. The grown crystals characterized by Fourier Transform Infrared (FTIR) and Ultraviolet (UV) spectrum. The optimized structure, HOMO-LUMO, NBO and NLO properties of BLSOD were calculated and compared with early reported BLSOD structure using B3LYP method with 6-31G basis set as provided with Gaussian 5.0 software. The DFT theoretical calculation indicates the new change in the bonding interaction improved the NLO property compared to early reported structure of BLSOD. This may be due to the change in the molecular orientation.

A detailed high pressure study is carried out on 1T′ MoTe2 using x-ray diffraction (XRD) and Raman spectroscopy measurements up to about 30.5 GPa along with a room temperature resistivity measurement up to 14.3(4) GPa and density functional theory calculations. Though high-pressure XRD measurements show no structural transition, all the lattice parameters exhibit anomalous changes in the pressure region 8.4 to 12.7 GPa. The compressibility of the sample is found to be reduced by almost four times above 12.7 GPa with respect to that below 8.4 GPa. The anomalies in the Raman mode corresponding to the out of plane vibrations of Mo atoms sitting in the unit cell surface indicate a strong electron–phonon coupling possibly mediated by differential strain inside the unit cell. A rapid decrease in resistivity value up to about 7.0(2) GPa of pressure agrees well with the increase in the density of states (DOS) at the Fermi energy with pressure. Pressure evolution of band structure, as well as DOS at the Fermi level, shows an enhancement of the metallic character of the sample. First principle calculations show increased stress in the x and y directions compared to the z-direction with the application of pressure.

New azo reagent was synthesized by reaction dizonium salt Sulfadiazine with Pyrogallol. This product was characterized by FTIR, UV. Visible spectrophotometer and (XRD). Purity of the dye was checked by thin layer chromatography (TLC) using solvent system (Toluene-Methanol) (2:3). The melting point of the purified dye was measured in an open capillary tube. The results showed this compound have high levels of antibacterial activity.

Based on a femtosecond laser plasma-induced hard x-ray source with a high laser pulse energy (> 100 mJ) at 10 Hz repetition rate, we present a time-resolved x-ray diffraction system on an ultrafast time scale. The laser intensity is at relativistic regime (2 × 1019 W/cm2), which is essential for effectively generating Kα source in high-Z metal material. The produced copper Kα radiation yield reaches to 2.5 × 108 photons/sr/shot. The multilayer mirrors are optimized for monochromatizating and two-dimensional beam shaping of Kα emission. Our experiment exhibits its ability of monitoring the transient structural changes in a thin film SrCoO2.5 crystal. It is demonstrated that this facility is a powerful tool to perform dynamic studies on samples and adaptable to the specific needs for different particular applications with high flexibility.

Topo-tomographic methods for identifying defects in semiconductors are the most effective among X-ray methods. Combining experimental data with model calculations makes it possible to determine various parameters and properties of crystal structures. In this work, using X-ray diffraction topo-tomography, images of the dislocation half-loop in Si (111) crystal were obtained. The Takagi-Taupin equations have been used to modeling the topograms. A quantitative comparison of the images made it possible to determine the direction of the Burgers vector.

The additional atomic occupancy in the octahedral and the tetrahedral voids of the face-centered cubic lattice (fcc) of fullerene C60was detected by neutron and x-ray powder diffraction. The observed occupancy exactly tracks the rearrangement of the orientation order with temperature decreases and results from the large atomic vibrations of the carbon atoms constituting the fullerene molecules. This motion assumes a small but finite probability to find the carbon atoms in the fcc interstitial voids, which is modeled by the detected 'phantom' occupancies.

In situ X-ray diffraction observation was done for neutron-irradiated and un-irradiated HOPG samples with synchrotron radiation to clarify the effect of irradiation-induced defects on the transformation to diamond under high-pressure and high-temperature treatment. At 16 GPa, no remarkable change appeared for the irradiated HOPG with increasing the temperature up to 800 °C. At temperatures of 1200 and 1400 °C, hexagonal diamond was formed, along with the formation of cubic diamond. This is probably due to annealing of the irradiation defects that led to partial restoration of the structure to the original HOPG and then enables the formation. On the other hand, in un-irradiated HOPG, hexagonal diamond was formed at 400 °C, which changed to cubic diamond at 1200 °C or higher. We guess that irradiation defects promote the nucleation of cubic diamond in the irradiated sample and then contribute to the formation of isotropic polycrystalline diamond or amorphous diamond.

Ternary intermetallic compound SmRuSn2 was synthesized in the system Sm-Ru-Sn by arc-melting and annealing at 600 °C in field with high content of Sn. Its crystal structure was determined from single crystal X-ray diffraction data (at 240 K) and then confirmed by the powder X-ray diffraction data (at 295 K). The compound crystallizes in with space group Cmcm (No. 63), unit cell unit cell parameters: a=4.3954(19) Å, b=10.3783(13) Å, c=7.417(2) Å, Z=4. The intermetallic compound SmRuSn2 belongs to the structure type MgCuAl2.

Electron density plays an important role in determining the properties of functional materials. Revealing the electron density distribution experimentally in real space can help to tune the properties of materials. Spinel LiMn2O4 is one of the most promising cathode candidates because of its high voltage, low cost, and non-toxicity, but suffers severe capacity fading during electrochemical cycling due to the Mn dissolution. Real-space measurement of electron distribution of LiMn2O4 experimentally can provide direct evaluation on the strength of Mn–O bond and give an explanation of the structure stability. Here, through high energy synchrotron powder x-ray diffraction (SPXRD), accurate electron density distribution in spinel LiMn2O4 has been investigated based on the multipole model. The electron accumulation between Mn and O atoms in deformation density map indicates the shared interaction of Mn–O bond. The quantitative topological analysis at bond critical points shows that the Mn–O bond is relatively weak covalent interaction due to the oxygen loss. These findings suggest that oxygen stoichiometry is the key factor for preventing the Mn dissolution and capacity fading.

Metal halide perovskites attract significant interest due to their remarkable performance in optoelectronic devices. However, the gap in understanding the relationship between their nanoscale structure and properties limits their application towards novel devices. In this work, twinned ferroelastic domains in single 500 nm CsPbBr3 particles are studied with 3D Bragg coherent x-ray diffraction imaging. A preferential double-domain structure is revealed in four identical particles, with one domain oriented along the [110] and the other along the [002] direction. The particles exhibit similar scattering volume ratios of 0.12 ± 0.026 between twin phases, suggesting the possibility of a deterministic formation process. The domains exhibit a difference in lattice tilt of 0.59 degrees, in excellent agreement with calculations of the lattice mismatch at the (112) twin boundary. These results provide important insights both for the fundamental understanding of ferroelastic nanoscale materials and for the performance improvement of perovskite-based devices. Moreover, this work paves the way towards real-time imaging of the domain dynamics in ferroic systems.

We examine electronic and crystal structures of iron-based superconductors LnFeAsO1−x H x (Ln = La, Sm) under pressure by means of x-ray absorption spectroscopy (XAS), x-ray emission spectroscopy (XES), and x-ray diffraction. In LaFeAsO the pre-edge peak on high-resolution XAS at the Fe-K absorption edge gains in intensity on the application of pressure up to 5.7 GPa and it saturates in the higher pressure region. We found integrated-absolute difference values on XES for Ln = La, corresponding to a spin state, decline on the application of pressure, and then it is minimized when the T c approaches the maximum at around 5 GPa. In contrast, such the optimum value was not detected for Ln = Sm. We reveal that the superconductivity is closely related to the lower spin state for Ln = La unlike Sm case. We observed that As height from the Fe basal plane and As–Fe–As angle on the FeAs4 tetrahedron for Ln = La deviate from the optimum values of the regular tetrahedron in superconducting (SC) phase, which has been widely accepted structural guide to SC thus far. In contrast, the structural parameters were held near the optimum values up to ∼15 GPa for Ln = Sm.

The structure of Cu67Zr33 amorphous alloy was investigated in terms of packing density and free volume by using neutron, x-ray diffraction and reverse Monte Carlo (RMC) modelling. The RMC model was analysed by a method of decomposing the three-dimensional atomic configuration into fundamental polyhedral units (termed as ‘holes’ referencing the Bernal’s works) of which faces are all triangles consisting of chemical bonds. Not only tetrahedral and octahedral holes but also other larger holes were identified. Moreover, the atomic packing fractions and free volumes in the respective polyhedral holes were evaluated with reference to those for the corresponding crystal structures. The results show that the distribution of free volumes for the larger holes can be described by the exponential function assuming that there are no energetic interactions between each other. On the other hand, the local structural fluctuations due to densely and loosely packed tetrahedral holes were observed, leading to the negative free volume spaces.

Structural properties of the organic-inorganic hybrid (C2H5NH3)2CuCl4 (EA2CuCl4) have been investigated by means of x-ray powder diffraction and Rietveld analysis. A structural phase transition from Pbca to Aba2 occurs at T 4 = 240 K, which results in a paraelectric–ferroelectric phase transition. The release of the Jahn–Teller distortion with increasing temperature toward T 4 is revealed by the structural analysis.

Research using X-ray diffraction (XRD) remains to be accelerated in spite of its importance in materials science. Automated noise separation or optimization of measurement time in XRD is beneficial for discovering materials. This study analyzes two-dimensional XRD (2D-XRD) with density-based clustering to accelerate XRD. This clustering technique can separate diffraction pattern signals from noises, even with low signal-to-noise ratio (S/N) 2D-XRD. Moreover, we found that the crystalline degree information in composition spreads is captured based on density. This information requires a long time to be captured with conventional one-dimensional detectors or scintillation counters. Therefore, these findings lead to dramatic reduction and optimization of measurement time to improve S/N. The proposed procedure is applicable with 2D detector measurements.

Layered LiNi x Co y Mn1-x-y O2 (NCM) is expected to dominate the future cathode technology of the automotive industry, due to its high energy density and low cost. Despite its excellent prospects, however, the severe capacity decay of NCM cathodes has prevented this promising material from achieving further success. The mechanism underlying this phenomenon is controversial and has been generally understood as arising from the complex structural changes that take place upon Li-(de)intercalation. However, deeper insight has not been available due to unclear structural kinetics, in particular, in cycled NCM cathodes. For this study, we conducted in situ high-energy synchrotron x-ray diffraction (XRD) measurements on a typical LiNi0.5Co0.2Mn0.3O2 (NCM523) cathode that had been operated for 90 cycles, then compared the results with those collected from a fresh NCM532 electrode. It was revealed that the H1–H2 phase transition that only occurs at the first cycle is irreversible. Remarkably, the c-contraction triggered by the H2-H3 transition, which is expected to be the major cause of intergranular cracks in electrodes, became even more profound after cycling. Combining the above results with electrochemical testing and microscopic imaging, we discuss the interplay between structural dynamics and performance degradation in NCM532 in detail. This study provides key evidence for a mechanically induced capacity decay mechanism, which is expected to be extended to NCM materials with various compositions.

In this paper we perform a high-pressure (HP) study of fergusonite-type HoNbO4. Powder x-ray diffraction experiments and ab initio density-functional theory (DFT) simulations provide evidence of a phase transition at 18.9(1.1) GPa from the monoclinic fergusonite-type structure (space group I2/a) to another monoclinic polymorph described by space group P21/c. The phase transition is reversible and the HP structural behavior is different than the one previously observed in related niobates. The HP phase remains stable up to 29 GPa. The observed transition involves a change in the Nb coordination number from 4 to 6, and it is driven by mechanical instabilities. We have determined the pressure dependence of unit-cell parameters of both phases and calculated their room-temperature equation of state. For the fergusonite-phase we have also obtained the isothermal compressibility tensor. In addition to the HP studies, we report ambient-pressure Raman and infrared (IR) spectroscopy measurements. We have been able to identify all the active modes of fergusonite-type HoNbO4, which have been assigned based upon DFT calculations. These simulations also provide the elastic constants of the different structures and the pressure dependence of the Raman and IR modes of the two phases of HoNbO4. According to ab initio calculations, the reported phase transition is related to a mechanical instability and a phonon softening.

In this work, high quality AlGaN layers, grown by metal organic chemical vapour deposition, on a commercial c-sapphire substrate, were implanted at a fluence of 1 × 10 14 A r + ⋅ c m − 2 . Implantation was performed for energies between 25 and 250 keV to explore the strain field created with increasing penetration of the implanted ions. Perpendicular to the sample surface deformation was determined through simulations of the 2 θ − ω scans of the allowed (0002), (0004) and (0006) AlGaN reflections. According to the simulations, the peak attributed to the implanted region is well defined using a small number of layers with specific thickness, deformation, and static Debye–Waller factors. Although similar ion end of range, calculated via Monte Carlo simulations of ions in matter, of around 240–250 nm for 200 keV implanted normal to the sample surface and 250 keV at 38°, the strain distribution in depth turns out quite different in these samples. According to dynamical theory of x-ray diffraction simulations, the argon ions penetrate deeper on the former, which might be related to channeling effects, while maximum damage is observed in the latter. Damage accumulation is suggested to be a complex mechanism, where damage maximum and damage extension play equivalent important roles.

The self-propagated exothermic reaction characteristics of Al/Ni multilayer powders can be employed as heat sources and controlled by cold-rolling conditions. This feature depends on the heat propagation inside of crystal grains. Therefore, the crystallographic factor that relates cold-rolling conditions to exothermic characteristics should be identified. To determine the change trend in crystallite size with the increase in the number of rolling passes, the crystallite sizes in the Al/Ni multilayer powder were calculated using Scherrer’s equation, and precise X-ray profiles were obtained using the synchrotron radiation X-ray diffraction method. The results indicate that the crystallite sizes were refined by increasing the number of rolling passes up to 30; from 30 to 40 passes, however, the crystallite sizes increased. It is assumed that, in addition to the Al/Ni multilayer powder being thin and multilayered, the increase in crystallite size at 40 passes allows for the smooth propagation of heat, consequently improving the exothermic characteristics. Therefore, crystallite size is the dominant parameter in the relationship between rolling conditions and exothermic characteristics.

We present detailed studies on spinel structured Ni0.5Co x Zn0.5−x Fe2O4 (x = 0.1, 0.2 and 0.3), synthesized by sol–gel combustion method. In addition to the structural properties, we present optical dielectric and magnetic response of this system as a function of x. From x-ray diffraction analysis, a single-phase formation in cubic spinel structure was confirmed with an average crystallite size (D avg) variation of 46–61 nm. X-ray diffractograms were analyzed to evaluate the lattice constant (a), x-ray density (ρ x) and porosity (P) in percentage. Energy dispersive x-ray spectroscopy was used to delimit the compositional mass ratios. Terahertz (THz) time-domain spectroscopy measurements were performed to investigate the refractive index ( n ˆ s ) of the samples at room temperature in a frequency range from 0.2 to 2.5 THz. Real and imaginary components of complex optical dielectric constant ( ε ˆ s ) with the increase of Co2+ content were deduced using THz spectroscopy data. The complex optical dielectric constant for the substitution of Co2+ content at x = 0.1, 0.2 and 0.3, was determined within 5% error ∼9.6 + i0.07, ∼10.9 + i0.2 and ∼11.7 + i0.5, respectively. The magnetic measurements were performed at a temperature range of 300–50 K using a superconducting quantum interference device vibrating sample magnetometer under an applied magnetic field of ±5 tesla. We found the highest saturation magnetization (M s) of about 86.7 emu g−1, 83.5 emu g−1 and 80.4 emu g−1 for the substitution of Co2+ content at x = 0.1, 0.2 and 0.3, respectively at room temperature.

This study was conducted in Duhok Governorate (DG) to study the mineralogical and chemical properties of atmospheric falling dust (AFD) and to measure the fall rate of AFD. AFD samples were collected at different locations and times by a funnel on the nozzle of a plastic bucket (pail) of dimensions (1 m2) on the veranda of the building, ∼3-4 m high the ground level. To compare between chemical properties of AFD and street dust that people are exposed to, the dust accumulated on car engine air-filters (CAFs) have been examined. Atomic absorption spectrometry (AAS) was used to study the chemical composition of the particles. X-ray diffraction (XRD) was used to investigate mineralogical characterization. The result shows that the traffic emissions and increasing population density as anthropogenic sources, in addition to natural dust particles in Duhok governorate have been the main role in the dust fall rate. The results show that the monthly dust fall rate was recorded in Duhok (3.35 gm/m2.month). The higher average concentration value for heavy metal was (Cu=11.5 ppm). The study includes qualitative identification of clay minerals by X-ray diffraction data. Peak height was used as a rough indicator of the relative abundance of minerals. The major minerals observed in the AFD sample are Calcite (CaCO3), Quartz low, Silicon Oxide (SiO2), and Dolomite (CaMg(CO3)2).

The article represents the results of the research of the mammoth tuskMammuthus Primigeniususing thermogravimetric (TGA) and X-ray diffraction analysis (XRD). The stages of thermal destruction of mammoth tusk components and their temperature limits are revealed. XRD of mammoth tusk showed that heat treatment leads to a change in the structure of the mineral component of the material under study from hydroxyapatite (HAP) to whitlockite. It was found that this process is caused by the presence of magnesium ions in the crystal lattice of HAP.

The optical properties of Al x Ga1−x N-based quantum wells (QWs) with various thicknesses are investigated. When the Al x Ga1−x N thickness in Al0.8Ga0.2N/AlN QWs exceeds 6 nm, the photoluminescence lifetime is drastically shortened even at cryogenic temperatures, which indicates that nonradiative recombination processes are enhanced. Interestingly, the thicknesses for the degradation of the optical properties of Al x Ga1−x N on AlN (0001) are about two orders of magnitude thinner than the critical layer thicknesses for lattice relaxation determined by a conventional X-ray diffraction method. To avoid the degradation of the QW optical properties, Al y Ga1−y N (y > x) underlying layers are effective.

Multi-cations lead perovskite solar cells have shown higher performance than single-cation perovskite solar cells. This compositional engineering of perovskite material retains the optimum tolerance factor while allowing the tuning of the band gap in addition to the enhanced stability of cubic phase perovskite. However, no in-depth explanation has been provided on the relationship between crystal structure of the perovskite and the solar cell efficiency. In this report, we investigate the effect of lattice disordering of FA x MA1−x PbI3 perovskite on the tolerance factor and solar cell efficiency. The lattice disordering estimated using Williamson–Hall plot of XRD analysis revealed that the disordering is lowest when x = 0.2 and highest when x = 1.0. Correspondingly, x = 0.2 showed the highest solar cell performance and long carrier lifetime Our results show that the disordering in α phase of FA x MA1−x PbI3 layer causes lattice deformation which affects the carrier lifetime and solar cell efficiency, instead of the defects on constituent elements.

The structural and electronic properties of In2O3 epitaxial films grown on c-sapphire substrates by a pulsed laser deposition technique are studied as functions of various growth conditions. Our study shows that growth temperature, growth time, oxygen partial pressure, and post-growth cooling conditions play important roles in governing the magnitude and character of the overall change in unit cell volume (volume strain) of the lattice. It is found that biaxial strain, which is developed due to lattice and thermal expansion coefficient mismatches between the layer and the substrate, leads to overall compression of the lattice. Interestingly, a hydrostatic tensile strain is found to coexist with biaxial strain in samples, which, following growth, are cooled to room temperature at a rate much slower than the natural rate of cooling. It has been observed that the overall strain can be varied from compressive to tensile by changing the growth parameters. The study further shows a systematic variation of the bandgap (from 3.8 to 3.1 eV) with a change in the unit cell volume of these layers, demonstrating the strong influence of strain on the band structural properties of the material.

Synthesis of functional nanostructured materials using solution-based low-cost deposition routes is an emerging research area. In this paper, we report deposition of one such material, Copper Sulphide nanostructures (CuS NS), using low-cost chemical bath deposition technique. The films have been deposited on bare glass substrate from a precursor (PS) bath prepared using reverse osmosis (RO) processed water (Drinking water). The deposition of the films has been carried out at three different temperatures, 60°, 65° and 70 °C. X-ray diffraction study confirmed the CuS NS film possess pure hexagonal covellite phase. Scanning Electron Microscopy of the films revealed the flower-like shape CuS NS are made up of hexagonal plates of side lengths ∼38 nm and thickness ∼4.76 nm. The average size of the agglomerated grains was calculated 65 nm to 665 nm (60 °C), 94 nm to 670 nm (65 °C) and 94 nm to 670 nm (70 °C) using ImageJ software. The optical study showed the films possess indirect and direct optical energy bandgap (Eg) in the range ∼1.3–1.6 eV and ∼2.4–2.7 eV, respectively.

Diffraction-based texture analysis plays a significant role in the investigation of the physical properties of materials. The development of computer-aided tools for this research area facilitates quantitative validation of proposed orientation distribution models. We analyze the differences between Bragg-Brentano and grazing-incidence diffraction experiments from the point of view of texture characterization. New software packages for modelling Bragg-Brentano and grazing-incidence (one- and two-dimensional) XRD patterns produced by axially-textured polycrystals are presented. A case study based on a virtual experiment with a BaTiO3 sample is presented. The effect of texture on the diffraction patterns obtained by application of the different techniques considered differs significantly.

Crystallite size is one of the critical powder characteristics to determine nano-scale properties used in many industrial applications. The crystallite size can be extracted by X-ray Diffraction (XRD) analysis since it is one of the simplest and the most convenient method among numerous characterization techniques. However, the lack of suitable uncertainty evaluation for determining crystallite size makes the measurement questionable. Therefore, this paper has presented the uncertainty evaluation for crystallite size measurement based on the method of JCGM 100:2008. The main contributions according to the Scherrer equation consist of the Scherrer constant (K), the X-ray wave length (λ), the full width of the peak at half maximum intensity (FWHM), the diffraction angle (θ), and also the resolution and repeatability effect. The measurement process, statement of the standard uncertainty of the component sources, sensitivity coefficient and the combined standard uncertainty of crystallite size measurement have been explained in detail. A numerical example presents how to estimate the uncertainty budget for the nanoparticle of TiO2 or P25 which is a commercially available powder.

This study focused on protein crystallization in high-strength hydrogels to expand the application of protein crystals. The results of our previous studies demonstrated several desirable merits, such as growth with a high nucleation rate and a high tolerance to solvent evaporation. However, the crystallization method faces the problem of handing protein solutions at high temperatures, which often causes the proteins to become inactivated or aggregated. This study established a new crystallization method that prevents high-temperature damage to proteins. This method offers a technique to osmose the protein from the top of a hydrogel layer and recover its crystals as the precipitant on the bottom of the hydrogel layer by using a handmade plate with a dialysis membrane. This study concentrated on the protein crystallization in hydrogels, but the results indicate that this method will be applicable to various proteins because it can always be operated at a low temperature.

Two-dimensional (2D) hexagonal boron nitride (h-BN) is becoming increasingly interesting for wider engineering applications. Thermal exfoliation is being suggested as a facile technology to produce large quantities of 2D h-BN. Further optimization of the process requires fundamental understanding of the exfoliation mechanism, which is hardly realized by ex situ techniques. In this study, in situ synchrotron x-ray powder diffraction experiments are conducted while heat treating bulk h-BN up to 1273 K. During the heating process, linear expansion of c-axis is observed and the contraction of a-axis up to around 750 K is consistent with previous research. However, a changing behavior from contraction to expansion in a-axis direction is newly observed when heating over 750 K. With the consideration of previous thermally oxidation studies, a hypothesis of thermal assisted exfoliation with oxygen interstitial and substitution of nitrogen at high temperature is proposed.