Using high-resolution x-ray scattering, we have demonstrated the existence of quenched disordered charge stripes in a single crystal of La (5/3)Sr (1/3)NiO (4) at low temperatures. Above the second-order transition critical scattering was observed due to fluctuations into the charge stripe phase. The charge stripes are shown to be two dimensional in nature both by measurements of their correlation lengths (xi(a) approximately 185 A, xi(b) = 400 A, and xi(c) approximately 25 A) and by the critical exponents of the charge strip transition. The charge stripe ordering did not develop long-range order even at low temperatures, indicating that the charge stripes are disordered and that the length scale of the disorder is quenched.

Screw‐assisted material extrusion technique is developed for tissue engineering applications to produce scaffolds with well‐defined multiscale microstructural features and tailorable mechanical properties. In this study, in situ time‐resolved synchrotron diffraction is employed to probe extrusion‐based 3D printing of polycaprolactone (PCL) filaments. Time‐resolved X‐ray diffraction measurements reveals the progress of overall crystalline structural evolution of PCL during 3D printing. Particularly, in situ experimental observations provide strong evidence for the development of strong directionality of PCL crystals during the extrusion driven process. Results also show the evidence for the realization of anisotropic structural features through the melt extrusion‐based 3D printing, which is a key development toward mimicking the anisotropic properties and hierarchical structures of biological materials in nature, such as human tissues.

By separately identifying magnetic and charge scatter, we find conclusive evidence for conformality in magnetic roughness in ͕Co ͑8 Å͒ Cu ͑9 Å͖͒ multilayers. For layers magnetized in the easy direction, the magnetic roughness equals the structural roughness but increases when magnetized in the hard direction. The in-plane magnetic correlation length, which changes on magnetization, is several orders of magnitude larger than the structural roughness length scales. The magnetic length scale is of the same order as magnetic ripple observed in Lorentz microscopy and is not associated with domains.

3D printing techniques are utilized to produce biomaterial scaffolds with porous architectures that enable cell attachment, biological factors, and appropriate mechanical strength. As the basic building block of a scaffold, the individual filaments should have sufficient mechanical properties, comprising high compressive loading, and fracture resistance to mimic the natural tissue organisation. In this contribution, process–structure–property relationships in melt extruded polycaprolactone filaments are investigated by considering crystalline features, tensile properties, and an array of processing parameters. The tensile properties of the filaments are improved significantly with relatively higher screw rotational speed and relatively lower processing temperature resulting in considerable increase in Young's modulus. The favorable properties are attributed to the increased crystal volume fraction and anisotropy. Thus, this study provides initial pathways for the potential control of mechanical properties of bioscaffolds via engineering crystalline structural features in printed filaments.

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