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The Coherent X‐ray Scattering beamline at the Pohang Light Source‐II was constructed in 2011 for coherent diffraction imaging and has now been upgraded in its focusing optics, diffractometer, detectors and endstation. The enhanced photon flux density and modified endstation have enabled routine Bragg coherent diffraction imaging and microbeam diffraction, while the newly implemented ptychography setup has enhanced nano‐imaging capability in transmission geometry. Because coherent diffraction imaging and microbeam diffraction share the same upstream optics, switching between techniques requires only minor adjustments to slit settings, mirror pitch and the sample‐to‐detector distance, enabling efficient integration of user programs without compromising instrument performance. This paper details the upgrade and the new capabilities of the beamline. Comprehensive upgrades to optics, detectors and the endstation at the CXS beamline have transformed its coherent diffraction imaging performance, enabling routine Bragg coherent diffraction imaging and microbeam diffraction, and adding the capability for transmission geometry nano‐imaging via ptychography.

To study the effects of particular process conditions and micro size factor on microstructures manufactured by micro-injection molding, four types of polypropylene micro column arrays are fabricated. The filling performance, morphology, and mechanical properties of these column arrays are investigated by polarized light microscopic, SEM, X-ray microbeam diffraction, nanoindentation, and microindentation. The process parameters are optimized by analyzing the filling performance of these micro columns under different process conditions. These micro columns represent “skin-core” structure and spherulite size diminishes gradually with the decrease of diameter of micro columns. Micro columns contain both α and β phase. The hardness and modulus of the same micro column increase from core zone to skin layer. There is no obvious difference of hardness among the micro columns with different diameters.

White X-ray microbeam diffraction was applied to investigate the microscopic deformation behavior of individual grains in a Cu-Al-Mn superelastic alloy. Strain/stresses were measured in situ at different positions in several grains having different orientations during a tensile test. The results indicated inhomogeneous stress distribution, both at the granular and intragranular scale. Strain/stress evolution showed reversible phenomena during the superelastic behavior of the tensile sample, probably because of the reversible martensitic transformation. However, strain recovery of the sample was incomplete due to the residual martensite, which results in the formation of local compressive residual stresses at grain boundary regions.

Poly(p-dioxanone) (PPDO) is crystallized with amorphous poly(p-vinyl phenol) (PVPh) and tannic acid (TA) as co-diluents to regulate and induce dendritic-ringed PPDO spherulites, with spoke- or sector-bands, aiming for convenience of analyses on interior lamellar assembly. Morphologies and interior lamellar arrangement leading to the peculiar rings on individual dendrites are evaluated by using polarized-light microscopy (PLM) and scanning electron microscope (SEM). Combinatory microbeam small-/wide-angle X-ray scattering (SAXS/WAXS) analyses further confirm the unique assembly patterns in periodic cycles. Alternate gratings are packed with periodic ridges composed of feather-like branches and the valley is featured with some embossed textures. The periodic gratings in the ringed spokes resemble those in nature’s structured coloration and are proven to display light-interference iridescence.

The degree of orientation in regenerated cellulose fibres with a diameter of 36μm was determined using position-resolved synchrotron X-ray microbeam diffraction. The fibres were characterized in unstrained condition, under tensile strain, and in bending. A homogeneous distribution of the degree of crystalline orientation (Herman’s orientation factor fc = 0.85) across the fibre thickness was found in the unstrained fibre. The degree of orientation of cellulose crystallites increased in a linear manner with increasing tensile strain applied to the fibre. Also in bending, a linear relationship between applied strain and the degree of crystalline orientation was found, where fc increased in tension and decreased in compression. This linear relationship was found to be valid for both the tensile and the compressive zone of the bent fibre.

The objective of this study is to clarify the effect of restoring the lowered masticatory muscle functional pressure and correcting bilateral differences in masticatory muscle functional pressure on jawbone growth during growth and development with a quantitative evaluation of the changes in the micro/nanostructural characteristics of entheses. Male Wistar rats aged 4 weeks were divided into an experimental group injected with a botulinum toxin serotype A (BoNT/A) formulation to reduce muscle function (BTX group) and a control group (CTRL group). They were euthanised after 6, 8, 10, 12, and 16 weeks after measuring the difference between the midline of the upper and lower incisors. The mandibles were harvested for histological examination, second harmonic generation imaging, and the quantitative evaluation of biological apatite (BAp) crystal alignment. The midline difference decreased with age in weeks. In rats from 6 weeks after BoNT/A administration to 12 weeks after administration, the collagen fibre bundle diameter was significantly smaller in the BTX group; the difference between the two groups decreased with increasing age. BAp crystal alignment was significantly different on the x-axis and the y-axis on the BTX group from 6 weeks after BoNT/A administration to 10 weeks after administration. Asymmetry of mandibular bone formation caused by load imbalance during growth could be corrected by the adjustment of the function of the masseter muscle on either side.

Combinatorial approach for discovering novel functional materials in the huge diversity of chemical composition and processing conditions has become more important for breakthrough in thin film electronic and energy-conversion devices. The efficiency of combinatorial method depends on the preparation of a reliable high-density composition thin-film library. The physico-chemical properties of each sample on the library should be similar to those of the corresponding samples prepared by one-by-one conventional methods. We successfully developed the combinatorial liquid source misted chemical deposition (LSMCD) method and demonstrated its validity in screening the chemical composition of Bi₃.₇₅LaxCe₀.₂₅₋xTi₃O₁₂ (BLCT) for high remanent polarization (Pr). LSMCD is a cheap promising combinatorial screening tool. It can control the composition up to ppm level and produce homogeneous multicomponent library. LSMCD method allows us to prepare BLCT thin-film library at the variation of 0.4 mol% of La. Maximum 2Pr is 35 μC/cm⁻² at x = 0.21. The intensity of (117) XRD peak is quantitatively related to 2Pr. Newly developed scanning piezoelectric deformation measurement for nano-sized samples using scanning probe microscope (SPM) is also found out to be reliable for determining the relative ranking of Pr value rapidly.

This chapter discusses the measurement of some characteristics of polymer structure and morphology that impact the polymer properties. Several different techniques are required to examine the structural characteristics in polymers at several length scales. The chapter describes two X‐ray diffraction (XRD) techniques that are commonly used in the characterization of the structure and morphology in polymers and polymer composites. The first is wide‐angle X‐ray scattering (WAXS) methods for determining crystal structure, disorder, and orientation. The second is small‐angle X‐ray scattering (SAXS) methods for analyzing the fibrillar and lamellar morphology in semicrystalline polymers. The chapter also highlights combination measurements such as simultaneous XRD and elongation, microbeam technique to map the spatial variation in structure, and grazing incidence diffraction (GID) to determine the variation in structure with depth. A combination of techniques, especially electron diffraction, is useful in determining the structures.

This chapter details the procedures associated with quantifying the stress state within crystalline materials through the use of x‐ray diffraction. Beginning with a description of the methods used to measure lattice strain, the steps required to transform this data into the full stress tensor, from uniaxial to triaxial stress states, are explained along with the assumptions associated with the governing mechanical models. The effects of sample microstructure and experimental considerations are discussed in the context of practical examples that employ both conventional and synchrotron‐based, microbeam x‐ray techniques to analyze both polycrystalline and single‐crystal samples.

This chapter contains sections titled: Introduction The Underlying Physics of Synchrotron Sources Diffraction Applications Exploiting High Source Brilliance High Q‐Resolution Measurements Applications of Tunability: Resonant Scattering Future: Ultrafast Science and Coherence References