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Electrochemical properties of Li7La3Zr2normalO12 (LLZ) were investigated to reveal its availability as a solid electrolyte for all-solid-state rechargeable batteries with a Li metal anode. After calcination at 1230°C , a well-sintered LLZ pellet with a garnet-like structure was obtained, and its conductivity was 1.8×10−4Scm−1 at room temperature. The cyclic voltammogram of the Li/LLZ/Li cell showed that the dissolution and deposition reactions of lithium occurred reversibly without any reaction with LLZ. This indicates that a Li metal anode can be applied for an LLZ system. A full cell composed of a LiCoO2/LLZ/Li configuration was also operated successfully at expected voltage estimated from the redox potential of Li metal and LiCoO2 . Simultaneously, an irreversible behavior was observed at the first discharge and charge cycle due to an interfacial problem between LiCoO2 and LLZ. The discharge capacity of the full cell was 15μAhcm−2 . These results reveal that LLZ is available for all-solid-state lithium batteries.

Fucoidan, a fucose-rich polysaccharide isolated from brown alga, is currently under investigation as a new anti-cancer compound. In the present study, fucoidan extract (FE) from Cladosiphon navae-caledoniae Kylin was prepared by enzymatic digestion. We investigated whether a combination of FE with cisplatin, tamoxifen or paclitaxel had the potential to improve the therapeutic efficacy of cancer treatment. These co-treatments significantly induced cell growth inhibition, apoptosis, as well as cell cycle modifications in MDA-MB-231 and MCF-7 cells. FE enhanced apoptosis in cancer cells that responded to treatment with three chemotherapeutic drugs with downregulation of the anti-apoptotic proteins Bcl-xL and Mcl-1. The combination treatments led to an obvious decrease in the phosphorylation of ERK and Akt in MDA-MB-231 cells, but increased the phosphorylation of ERK in MCF-7 cells. In addition, we observed that combination treatments enhanced intracellular ROS levels and reduced glutathione (GSH) levels in breast cancer cells, suggesting that induction of oxidative stress was an important event in the cell death induced by the combination treatments.

Lithium-ion cells with 5-Ah capacity were fabricated using a spinel Li 1.1 ͑Ni 0.025 Ti 0.025 Mg 0.02 ͒Mn 1.83 O 4 as a cathode active material, graphitized carbon as an anode active material, and 1 M LiPF 6 /ethylene carbonate + diethyl carbonate + dimethyl carbonate as an electrolyte. In order to improve the calendar life of the cell, we investigated the degradation mechanism by measuring the thickness of the solid electrolyte interphase ͑SEI͒ on anode active material. The SEI thickness was measured by focused ion beam, scanning electron microscope, and X-ray photoelectron spectroscopy. The thickness of the SEI was initially 0.04 m, and after storage for 392 days at 25 and 40°C, the thickness was 0.15 and 0.45 m, respectively. The capacity decreased with increase in the thickness of SEI, because Li in the cell is consumed by forming SEI. The amount of Li consumption was estimated theoretically assuming that SEI is formed by a reaction between intercalated Li and the electrolyte in SEI on the negative carbon surface, and a diffusion of the electrolyte in the SEI is the rate-determining step of the reaction. The theoretical equation showed a good agreement with experimental capacity fade at 25, 40, and 60°C for the storing days up to 380 days. A voltage decrease of the cell after 1-s at 20 A of discharge current was measured to estimate roughly the increase of the cell internal resistance during storage. The increase of SEI resistance was estimated by the theoretical equation and compared with the experimental voltage drop data after 1-s discharge. However, the theoretical data was not in a good agreement with the experimental data. The reason is that the charge-transfer resistance on the anode also increases during storage. Another reason is the resistance change of the cathode during the storage.