Nanometer-sized gold particles dispersed in organic liquids coagulate under the influence of addition of salt or illumination of Mie resonance irradiation. It is derived that the van der Waals attractive force can be enhanced by the excitation of surface plasmon, hence the rate of coagulation is accelerated through the DLVO (Derjaguin, Landau, Verway, Overbeek) potential among the particles. The coagulation rate and the stability ratio are calculated within a framework of DLVO theory.

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Compound crystallization is typically achieved from supersaturated solutions over time, through melting, or via sublimation. Here a new method to generate a single crystal of thioglucoside using a sub-10-fs pulse laser is presented. By focusing the laser pulse on a solution in a glass cell, a single crystal is deposited at the edge of the ceiling of the glass cell. This finding contrasts other non-photochemical laser-induced nucleation studies, which report that the nucleation sites are in the solution or at the air-solution interface, implying the present crystallization mechanism is different. Irradiation with the sub-10-fs laser pulse does not heat the solution but excites coherent molecular vibrations that evaporate the solution. Then, the evaporated solution is thought to be deposited on the glass wall. This method can form crystals even from unsaturated solutions, and the formed crystal does not include any solvent, allowing the formation of a pure crystal suitable for structural analysis, even from a minute amount of sample solution.

Exosomes are cell‐derived extracellular vesicles that hold promise for diagnosis and therapy. The surface characteristics of exosomes dictate their biological fate and are therefore important for various applications, however surface modification strategies are generally either limited in scope or require complex equipment or experimental procedures. Herein, we employ a simple and fast method to control the surface properties of exosomes via polydopamine coating. Specifically, the polydopamine coating allowed for tailorable functionalization via secondary reactions, which opens exciting avenues for the application of exosomes.

Hydroxyapatite(HA), Ca 10 (P0 4 )G(OH)2, is one of the most biocompatible materials with human bones. HA is a promising bone substitute material for clinical application because of clinical stability in vivo. Fine powder of HA were heated at 900°C for 1 h and at 1 000°C for 6 h in air. The first objective of this study is to reveal the effect of plastic flow on densification behavior by spark plasma sintering (SPS) from various preheated HA powders. From the isothermal shrinkage behavior, we concluded that the plastic flow in later stage does not depend on the preheating temperature. The second objective of this study is to prepare graduated HA ceramics for artificial bone by SPS. These heating powders (0.25 g) were vertically laminated into the graphite mold and then sintered by SPS at the temperatures from 800°C for 10 min with a heating rate of 25 K min-1 • The ceramics prepared by SPS had pores of about 0.1 [!m after heated at 1 000°C for 6 h. There were no pores in HA ceramics prepared by SPS before heated at 900°C for 1 h.