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Highlights: A series of layered oxide cathode materials were synthesized by high-temperature shock strategy for the first time. The approaching ultimate solid reaction rate of the layered nickel-rich layered oxide LiNixCoyMnzO2 was investigated for the first time. Ultrafast average reaction rate of phase transition from Ni0.6Co0.2Mn0.2(OH)2 to Li-containing oxides is 66.7 (% s-1), that is, taking only 1.5 s. Nickel-rich layered oxide LiNixCoyMnzO2 (NCM, x + y + z = 1) is the most promising cathode material for high-energy lithium-ion batteries. However, conventional synthesis methods are limited by the slow heating rate, sluggish reaction dynamics, high energy consumption, and long reaction time. To overcome these challenges, we first employed a high-temperature shock (HTS) strategy for fast synthesis of the NCM, and the approaching ultimate reaction rate of solid phase transition is deeply investigated for the first time. In the HTS process, ultrafast average reaction rate of phase transition from Ni0.6Co0.2Mn0.2(OH)2 to Li- containing oxides is 66.7 (% s−1), that is, taking only 1.5 s. An ultrahigh heating rate leads to fast reaction kinetics, which induces the rapid phase transition of NCM cathodes. The HTS-synthesized nickel-rich layered oxides perform good cycling performances (94% for NCM523, 94% for NCM622, and 80% for NCM811 after 200 cycles at 4.3 V). These findings might also assist to pave the way for preparing effectively Ni-rich layered oxides for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Graphite is a dominant anode material for lithium-ion batteries (LIBs) due to its outstanding electrochemical performance. However, slow lithium ion (Li+) kinetics of graphite anode restricts its further application. Herein, we report that high-temperature shock (HTS) can drive spent graphite (SG) into defect-rich recycled graphite (DRG) which is ideal for high-rate anode. The DRG exhibits the charging specific capacity of 323 mAh/g at a high current density of 2 C, which outperforms commercial graphite (CG, 120 mAh/g). The eminent electrochemical performance of DRG can be attributed to the recovery of layered structure and partial remaining defects of SG during ultrafast heating and cooling process, which can effectively reduce total strain energy, accelerate the phase transition in thermodynamics and improve the Li+ diffusion. This study provides a facile strategy to guide the re-graphitization of SG and design high performance battery electrode materials by defect engineering from the atomic level. [ABSTRACT FROM AUTHOR]

LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode material has potential practical application for high energy density lithium-ion batteries. However, it suffers from serious capacity degradation because of structural instability and cationic mixing during charging/discharging cycles. In this work, micron-sized single crystals Li1-xKxNi0.8Co0.1Mn0.1O2 (LKNCM) as composite cathode are successfully synthesized by molten salt-assisted growth method. LKNCM is regular plate-like polygon crystals (average grain size 1.31 μm) with flat face. K+ doping is helpful for the formation of Ni3+ and Co3+ in LKNCM crystals to some degree. Compared with pure NCM811, LKNCM possesses lower degree of Li+/Ni2+ mixing and ordered layered structure. LKNCM delivers initial capacity of 192 mAh g–1, and its capacity fading is less than 5% after 100 cycles at 0.1 C rate. Moreover, at 10 C rate it delivers initial capacity of 116 mAh g–1 (the median voltage of 3.4 V) and remains 95.2% of initial capacity after 180 cycles. The ex situ surface analysis on the cycled positive and negative electrodes reveals that K+ doping effectively suppresses side reaction and electrolyte decomposition during charging/discharging cycles. [ABSTRACT FROM AUTHOR]

A low-cost separable PCR chip, consisting of a reusable electrode part and a disposable PDMS-glass bonded chamber part, is presented. To achieve spatial uniformity of temperature over the whole reactive chamber, the heater of the electrode part with optimized electrode patterns based on traditional serpentine meanders was designed and simulated by using COMSOL Multiphysics. The separable PCR chip was fabricated using MEMS fabrication method. A temperature control thermal cycler system based on ARM microcontroller employing fuzzy-PID algorithm was constructed to provide the PCR required temperatures of denaturation, annealing and extension of each cycle. A thermal infrared imager was used to test the temperature distribution of the fabricated PCR chip. The temperature field simulation and infrared imager test verified that the heater with optimized electrode pattern can provide uniform temperature distribution in the area of the chamber where horizontal temperature fluctuation was within 1 °C. The performances of the microchip and the temperature control system were verified by β-actin gene PCR experiment. The 239 bp DNA segment of 6 μL sample in the micro-PCR chip was successfully amplified similarly to that in the conventional PCR instrument. The experiment proves that the fabricated PCR chip employing reusable heater of optimized electrode can provide efficient DNA amplification product while with less total time than the conventional PCR device. Multiple separable PCR chips with its reusable electrodes part employing the multi-channel thermal cycler system will be feasible for multiple DNA amplification. [ABSTRACT FROM AUTHOR]

Prostate cancer (PCa) is lethal type of genitourinary cancer due to its high morbidity and gradual resistance to androgen deprivation therapy. Accumulating evidence has recently suggested that the daily intake of flavonoids is negatively correlated with the risk of cancer. In this study, we aimed to investigate the potential effects of baicalein on androgen-independent PCa cells and the underlying mechanisms through which baicalein exerts its actions. Cell viability and flow cytometric apoptosis assays indicated that baicalein potently suppressed the growth and induced the apoptosis of DU145 and PC-3 cells in a time- and dose-dependent manner. Consistently, the inhibitory effects of baicalein on migration and invasion were also observed in vitro. Mechanistically, we found that baicalein can suppress caveolin-1 and the phosphorylation of AKT and mTOR in a time- and dose-dependent manner. Moreover, the inhibition of the activation of AKT with LY294002 significantly promoted the apoptosis and metastasis induced by baicalein. In conclusion, these findings suggested that baicalein can induce apoptosis and inhibit metastasis of androgen-independent PCa cells through inhibition of the caveolin-1/AKT/mTOR pathway, which implies that baicalein may be a potential therapeutic agent for the treatment of androgen-independent prostate cancer patients. [ABSTRACT FROM AUTHOR]