All-solid-state fluoride batteries have the potential to achieve energy densities significantly higher than those of lithium-ion batteries. A common cathode material for fluoride batteries is Cu. Cu has a low polarization, but its rapid capacity degradation due to grain growth and subsequent delamination from the solid-state electrolyte are critical issues.
View Article and Find Full Text PDFNanocrystal (NC) superlattices (SLs) have been widely studied as a new class of functional mesoscopic materials with collective physical properties. The arrangement of NCs in SLs governs the collective properties of SLs, and thus investigations of phenomena that can change the assembly of NC constituents are important. In this study, we investigated the dynamic evolution of NC arrangements in three-dimensional (3D) SLs, specifically the morphological transformation of NC constituents during the direct liquid-phase synthesis of 3D NC SLs.
View Article and Find Full Text PDFAn anomalous ultra-small-angle X-ray scattering (AUSAXS) system has been constructed at BL28XU at SPring-8 for time-resolved AUSAXS experiments. The path length was extended to 9.1 m and a minimum of = 0.
View Article and Find Full Text PDFConductive elastomers are promising for a wide range of applications in many fields due to their unique mechanical and electrical properties, and an understanding of the conductive mechanisms of such materials under deformation is crucial. However, revealing the microscopic conduction mechanism of conductive elastomers is a challenge. In this study, we developed a method that combines in situ deformation nanomechanical atomic force microscopy (AFM) and conductive AFM to successfully and simultaneously characterize the microscopic deformation and microscopic electrical conductivity of nanofiller composite conductive elastomers.
View Article and Find Full Text PDFAtomic force microscopy (AFM)-based nanoindentation technique has been widely used to investigate the mechanical properties of compliant specimens. When a sharp probe is indented into a soft and adhesive specimen, not only the rounded end of the probe but also the pyramidal base may be in contact. However, even in such a case, a contact model that assumes a paraboloidal tip geometry (the Hertz model or one of its expansions) is mainly employed to derive the mechanical properties; the error on the mechanical properties induced by the inaccurate tip geometry assumption has not been systematically clarified.
View Article and Find Full Text PDFWe experimentally studied the shear effect on dynamical heterogeneity near glass transition temperature. X-ray photon correlation spectroscopy was utilized to study the dynamics of polyvinyl acetate with tracer particles near its glass transition temperature, to determine the local shear rate from the anisotropic behavior of the time autocorrelation function and to calculate the dynamical heterogeneity using higher-order correlation function. The obtained results show a decrease in the dynamical heterogeneity and faster dynamics with increasing shear rate.
View Article and Find Full Text PDFInorganic/organic double network (DN) ion gels, which are composed of an inorganic silica particle network, an organic poly(N,N-dimethylacrylamide) (PDMAAm) network, and a large amount of ionic liquid, showed excellent mechanical strength of over 25 MPa compression fracture stress at an 80 wt% ionic liquid content. The excellent mechanical strength of these inorganic/organic DN ion gels was attributed to the energy dissipation of the inorganic/organic DN structure. It has been considered that the energy dissipation in inorganic/organic DN ion gels is caused by the internal fracture of the silica particle network, which is preferentially fractured by deformation.
View Article and Find Full Text PDFBiominerals such as bones and teeth have elaborate nanostructures composed of aligned anisotropic hydroxyapatite (HAp) nanocrystals, which results in excellent mechanical properties. Construction of such ordered structures of HAp nanocrystals in synthetic materials is challenging. Recently, we reported that HAp-nanorod-based colloidal liquid crystals could be obtained.
View Article and Find Full Text PDFWe review nano-palpation atomic force microscopy, which offers quantitative mechanical property mapping especially for soft materials. The method measures force-deformation curves on the surfaces of soft materials. The emphasis is placed on how both Hertzian and Derjaguin-Muller-Toporov contact mechanics fail to reproduce the experimental curves and, alternatively, how the Johnson-Kendall-Roberts model does.
View Article and Find Full Text PDFIndividual hairs can be inherently curly; however, bleach treatment can cause damaged hairs to acquire a curl, a phenomenon we term acquired unintentional unruly hair. Because there have been no reports concerning acquired unintentional unruly hair, the influence of bleach treatment with alkaline peroxide that produce this phenomenon was investigated. First, it was validated that the radius of curvature in many curly hairs is reduced upon bleach treatment.
View Article and Find Full Text PDFIn this report, we show the preparation of honeycomb scaffolds for cell culturing by using "breath figure" method, and we found that their mechanical and topographical properties strongly affect the adhesion of fibroblasts. By photo-cross-linking of the poly(1,2-butadiene), the hardness of the honeycomb scaffold can be successfully controlled without any surface chemical changes, and detail modulus values of scaffolds were measured by atomic force microscopy. We found that only small numbers of the cells adhered on the softer honeycomb scaffolds, which has even higher modulus value than conventional gels, comparing with flat films and a hard honeycomb scaffold.
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