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The photoexcited charge transfer properties of cephalopod chromatophore granules are examined within a photovoltaic cell. Photoconversion efficiency up to 0.81 ± 0.14% is recorded, highlighting a new function for these unique biomaterials. 

Nature is full of exemplary species that have evolved personalized sensors and actuating systems that interface with and adapt to the world around them. Among them, cephalopods are unique. They employ fast-sensing systems that trigger structural changes to impart color changes through biochemical and optoelectronic controls. These changes occur using specialized optical organs that receive and respond to signals (light, temperature, fragrances, sound, and textures) in their environments. We describe features that enable these functions, highlight engineered systems that mimic them, and discuss strategies to consider for future cephalopod-inspired sensor technologies. 

Subduction zones are often characterized by the presence of strong trench-parallel seismic anisotropy and large delay times. Hydrous minerals, owing to their large elastic anisotropy and strong lattice preferred orientations (LPOs), are often invoked to explain these observations. However, the elasticity and the LPO of chloritoid, which is one of such hydrous phases relevant in subduction zone settings, are poorly understood. In this study, we measured the LPO of polycrystalline chloritoid in natural rock samples, obtained the LPO-induced seismic anisotropy, and evaluated the thermodynamic stability field of chloritoid in subduction zones. The LPO of chloritoid aggregates displayed a strong alignment of the [001] axes subnormal to the rock foliation, with a girdle distribution of the [100] axes and the (010) poles subparallel to the foliation. New elasticity data of single-crystal chloritoid showed a strong elastic anisotropy of chloritoid with 47% for S-waves (V S ) and 22% for P-waves (V P ), respectively. The combination of the LPO and the elastic anisotropy of the chloritoid aggregates produced a strong S-wave anisotropy with a maximum AV S of 18% and a P-wave anisotropy with an AV P of 10%. The role of chloritoid LPO in seismic anisotropy was evaluated in natural rock samples and a hypothetical blueschist. Our results indicate that the strong LPO of chloritoid along the subduction interface and in subducting slabs can influence the trench-parallel seismic anisotropy in subduction zones with “cold” geotherms. 

Abstract Geopolymers, as a potentially environmentally friendly alternative to Portland cement, are increasingly attracting attention in the construction industry. Various methods have been applied for customizing the properties of geopolymers and improving their commercial viability. One of the promising methods for refining the properties of geopolymers such as their toughness is the use of short fibers. The effectiveness of a high‐strength short fiber in the geopolymer matrix is largely dependent on the interfacial bonding between the fiber and its surrounding matrix. While the importance of this interfacial chemistry is highlighted in the literature, the characteristics of this bonding structure have not been fully understood. In this paper, we aim to investigate the bonding mechanism between the carbon fiber and metakaolin‐based geopolymer matrix. For the first time, the existence and nature of the chemical bonding at the interfacial region (interphase) between carbon fiber and geopolymer matrix has been revealed. X‐ray pair distribution function computed tomography (PDF‐CT), field emission‐scanning electron microscopy imaging, and nanoindentation techniques are employed to discern the chemo‐mechanical properties of the interphase. PDF‐CT results show the emergence of a new atom–atom correlation at the interfacial region (around 1.82 Å). This correlation is a characteristic of interfacial bonding between the fiber and its surrounding matrix, where the existence of chemical linkages (potentially^VAl‐O‐C) between fibers and the matrix contributes to the adhesion between the two constituents making up the composite. Due to such chemical bonding, the nanomechanical properties of the interfacial region fall between that of the carbon fiber and geopolymer. The combination of advanced techniques is proved useful for enhancing our understanding of the interfacial chemistry between fibers and the binding matrix. This level of knowledge facilitates the engineering of composite systems through the manipulation of their nanostructure.