Boosting Superior Lithium Storage Performance of Alloy‐Based Anode Materials via Ultraconformal Sb Coating–Derived Favorable Solid‐Electrolyte Interphase

Alloy materials such as Si and Ge are attractive as high‐capacity anodes for rechargeable batteries, but such anodes undergo severe capacity degradation during discharge–charge processes. Compared to the over‐emphasized efforts on the electrode structure design to mitigate the volume changes, understanding and engineering of the solid‐electrolyte interphase (SEI) are significantly lacking. This work demonstrates that modifying the surface of alloy‐based anode materials by building an ultraconformal layer of Sb can significantly enhance their structural and interfacial stability during cycling. Combined experimental and theoretical studies consistently reveal that the ultraconformal Sb layer is dynamically converted to Li3Sb during cycling, which can selectively adsorb and catalytically decompose electrolyte additives to form a robust, thin, and dense LiF‐dominated SEI, and simultaneously restrain the decomposition of electrolyte solvents. Hence, the Sb‐coated porous Ge electrode delivers much higher initial Coulombic efficiency of 85% and higher reversible capacity of 1046 mAh g−1 after 200 cycles at 500 mA g−1, compared to only 72% and 170 mAh g−1 for bare porous Ge. The present finding has indicated that tailoring surface structures of electrode materials is an appealing approach to construct a robust SEI and achieve long‐term cycling stability for alloy‐based anode materials

In Situ Construction of an Ultrarobust and Lithiophilic Li-Enriched Li–N Nanoshield for High-Performance Ge-Based Anode Materials

Alloy-based materials are promising anodes for rechargeable batteries because of their higher theoretical capacities in comparison to graphite. Unfortunately, the huge volume changes during cycling cause serious structural degradation and undesired parasitic reactions with electrolytes, resulting in fragile solid-electrolyte interphase formation and serious capacity decay. This work proposes to mitigate the volume changes and suppress the interfacial reactivity of Ge anodes without sacrificing the interfacial Li+ transport, through in situ construction of an ultrarobust and lithiophilic Li-enriched Li–N nanoshield, which demonstrated improved chemical, electrochemical, mechanical, and environmental stability. Therefore, it can serve as a versatile interlayer to facilitate Li+ transport and effectively block the attack of electrolyte solvents, thus boosting the long-term cycle stability and fast charging capability of Ge anodes. This work offers an alternative methodology to tune the interfaces of other electrode materials as well by screening for more N-containing compounds that can react with Li+ during battery operation

Reliability Oriented Performance Testing System of Chain-type Magazine and ATC

Abstract: Tool magazine and ATC (Automatic Tool Changer) are crucial functional components and the weak links of the fault locations of the CNC machining center. So the study on reliability of magazine and ATC is important to improve the reliability of machining center. The failure of magazine and ATC is a gradual progress from quantitative to qualitative, with the changes of some performance parameters (such as vibration, noise, position accuracy, etc.). To provide a test basis for the reliability growth technology based on performance parameters changing, a set of reliability oriented performance test system of chain-type magazine and ATC is developed. The testing of performance parameters such as the kinematical characteristic of manipulator, the magazine positioning error, vibration on the tool oriented part and noise is achieved. Then the developed reliability oriented performance test system of chain-type magazine and ATC is used to estimate the performance of chain-type magazine and ATC produced by Dalian Golden CNC Group Corp. The experimental data proves its feasibility. Under reasonable test time interval and performance parameters changing thresholds, this system will alert the operators to do some repairing in time when performance parameters degrade badly to prevent the failures effectively so as to avoid or decrease losses, then the reliability of magazine and ATC can be improved

Reliability Oriented Performance Testing System of Chain-type Magazine and ATC

Tool magazine and ATC (Automatic Tool Changer) are crucial functional components and the weak links of the fault locations of the CNC machining center. So the study on reliability of magazine and ATC is important to improve the reliability of machining center. The failure of magazine and ATC is a gradual progress from quantitative to qualitative, with the changes of some performance parameters (such as vibration, noise, position accuracy, etc.). To provide a test basis for the reliability growth technology based on performance parameters changing, a set of reliability oriented performance test system of chain-type magazine and ATC is developed. The testing of performance parameters such as the kinematical characteristic of manipulator, the magazine positioning error, vibration on the tool oriented part and noise is achieved. Then the developed reliability oriented performance test system of chain-type magazine and ATC is used to estimate the performance of chain- type magazine and ATC produced by Dalian Golden CNC Group Corp. The experimental data proves its feasibility. Under reasonable test time interval and performance parameters changing thresholds, this system will alert the operators to do some repairing in time when performance parameters degrade badly to prevent the failures effectively so as to avoid or decrease losses, then the reliability of magazine and ATC can be improved

Effects of 8-Week Tai Chi Chuan Practice on Mindfulness Level

Objectives Tai Chi Chuan (TCC) is a common mindfulness-based aerobic exercise. However, the evidence on the effects of TCC practice on mindfulness has been controversial. The aim of this study was to explore whether TCC practice with an emphasis on interoceptive awareness could improve mindfulness levels in a healthy adult population. Methods Sixty-one healthy adults without mind-body practice experience were divided into the TCC and control groups. Participants in the TCC group received classic Yang-style supervised TCC practice for 8 weeks, whereas those in the control group did not receive any intervention. The Five Facet Mindfulness Questionnaire and Multidimensional Assessment of Interoceptive Awareness were administrated at baseline, the end of week 8, and the end of week 24. Results In terms of mindfulness, significant interaction between group and time was found in describing, acting with awareness, nonjudging, and nonreactivity. For interoceptive awareness, there were marginally significant interaction effects of time and group in attention regulation, self-regulation, and trust. TCC practice significantly improved the above-mentioned dimensions of mindfulness and interoceptive awareness. Moreover, we still observed increased describing, acting with awareness, and nonjudging in mindfulness, and trusting in interoceptive awareness for the TCC group at the end of week 24. Conclusions This study indicated that 8-week TCC practice with a component of interoceptive awareness could increase mindfulness levels, which could still be observed in the 24th week. These findings are of great significance for health practice and treating emotional disorders utilizing mind-body practice as an alternative and complementary medicine

Evaluation of the Performance of Low-Cost Air Quality Sensors at a High Mountain Station with Complex Meteorological Conditions

Low-cost sensors have become an increasingly important supplement to air quality monitoring networks at the ground level, yet their performances have not been evaluated at high-elevation areas, where the weather conditions are complex and characterized by low air pressure, low temperatures, and high wind speed. To address this research gap, a seven-month-long inter-comparison campaign was carried out at Mt. Tai (1534 m a.s.l.) from 20 April to 30 November 2018, covering a wide range of air temperatures, relative humidities (RHs), and wind speeds. The performance of three commonly used sensors for carbon monoxide (CO), ozone (O3), and particulate matter (PM2.5) was evaluated against the reference instruments. Strong positive linear relationships between sensors and the reference data were found for CO (r = 0.83) and O3 (r = 0.79), while the PM2.5 sensor tended to overestimate PM2.5 under high RH conditions. When the data at RH >95% were removed, a strong non-linear relationship could be well fitted for PM2.5 between the sensor and reference data (r = 0.91). The impacts of temperature, RH, wind speed, and pressure on the sensor measurements were comprehensively assessed. Temperature showed a positive effect on the CO and O3 sensors, RH showed a positive effect on the PM sensor, and the influence of wind speed and air pressure on all three sensors was relatively minor. Two methods, namely a multiple linear regression model and a random forest model, were adopted to minimize the influence of meteorological factors on the sensor data. The multi-linear regression (MLR) model showed a better performance than the random forest (RF) model in correcting the sensors’ data, especially for O3 and PM2.5. Our results demonstrate the capability and potential of the low-cost sensors for the measurement of trace gases and aerosols at high mountain sites with complex weather conditions