Although different kinds of metal oxide nanoparticles continue to be proposed as anode materials for lithium ion batteries (LIBs), their cycle life and power density are still not suitable for commercial applications. Metal oxide nanoparticles have a large storage capacity, but they suffer from the excessive generation of solid-electrolyte interphase (SEI) on the surface, low electrical conductivity, and mechanical degradation and pulverization resulted from severe volume expansion during cycling. Herein we present the preparation of mesoporous iron oxide nanoparticle clusters (MIONCs) by a bottom-up self-assembly approach and demonstrate that they exhibit excellent cyclic stability and rate capability derived from their three-dimensional mesoporous nanostructure. By controlling the geometric configuration, we can achieve stable interfaces between the electrolyte and active materials, resulting in SEI formation confined on the outer surface of the MIONCs.

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The effect of relative density on the hardness and fracture toughness of Al-substituted cubic garnet Li 6.19 Al 0.27 La 3 Zr 2 O 12 (LLZO) was investigated. Polycrystalline LLZO was made using solid-state synthesis and hot-pressing. The relative density was controlled by varying the densification time at fixed temperature (1050°C) and pressure (62 MPa). After hotpressing, the average grain size varied from approximately 2.7-3.7 lm for the 85% and 98% relative density samples, respectively. Examination of fracture surfaces revealed a transition from inter-to intragranular fracture as the relative density increased. The Vickers hardness increased with relative density up to 96%, above which the hardness was constant. At 98% relative density, the Vickers hardness was equal to the hardness measured by nanoindentation 9.1 GPa, which is estimated as the single-crystal hardness value. An inverse correlation between relative density and fracture toughness was observed. The fracture toughness increased linearly from 0.97 to 2.37 MPa√m for the 98% and 85% relative density samples, respectively. It is suggested that crack deflection along grain boundaries can explain the increase in fracture toughness with decreasing relative density. It was also observed that the total ionic conductivity increased from 0.0094 to 0.34 mS/cm for the 85%-98% relative density samples, respectively. The results of this study suggest that the microstructure of LLZO must be optimized to maximize mechanical integrity and ionic conductivity.

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Our study showed that serum osteocalcin has some significance as an indicator of metabolic risk, including abdominal obesity and insulin resistance. Bone as well as adipose tissue may be an active organ that regulates energy metabolism. A larger study will be needed to clarify the potential of osteocalcin as an indicator of cardiovascular disease.

The results support a central role for MIS in endometriosis. Although the precise mechanism of MIS-mediated inhibition of ESC growth has not been fully defined, these data suggest that MIS has activity against ESC in vitro and may also be an effective targeted therapy for endometriosis.

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