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The development of Na-ion full cells (NIFCs) suffers from the issue that the solid electrolyte interphase formation on the carbon anode consumes the limited sodium from cathode and thus incurs the decreased energy density and poor cyclic stability. To address these issues, we herein report that Na2O2 could be used as a sacrificial Na source through spraying its slurry on the surface of cathode, and investigate its stability as well as electrochemical behavior toward NIFCs. The results show that Na2O2 has good chemical and storage stability under a dry atmosphere and has no negative effect on the electrochemical performance of the cathode. Compared with the pristine cathode, the Na2O2-decorated cathode exhibits higher discharge capacity, superior capacity retention, and rate capability in a full cell with a carbon anode. Our cathode Na compensation strategy provides an effective avenue to make up for the irreversible Na+ loss cause by the formation of solid electrolyte interphase on the anode, thereby promoting the electrochemical performance and energy density of NIFCs toward the large-scale application.

Recycling of spent lithium-ion batteries has recently become a critical issue based on environmental concerns and a desire to reutilize resources. Among the existing recycling strategies, direct regeneration is largely encouraged from an economic and environmental perspective. However, current procedures used to separate the active cathode materials from the aluminum foil have some limitations for direct regeneration because they either destroy the structure of the cathode or use too many toxic and expensive reagents. Hence, we conducted comprehensive research on the microstructural evolution of the LiNi1−x−yCoxMnyO2 degraded electrode and then proposed a targeted method to recycle the spent cathode materials based on the increased residual lithium compounds. This separation process involves no other reagents but water, and toxic organic solvents, complicated processes, and waste treatments are unnecessary compared with the existing pretreatment strategies. Moreover, the separated cathodes are suitable for direct regeneration. Satisfactory capacity recovery of the cathode was achieved via simple sintering. Such a recycling process enables a sustainable closed-loop for the spent cathodes and provides new inspiration for the design of LIB recycling.

Na-ion cathode materials operating at high voltage with a stable cycling behavior are needed to develop future high-energy Na-ion cells. However, the irreversible oxygen redox reaction at the high-voltage region in sodium layered cathode materials generates structural instability and poor capacity retention upon cycling. Here, we report a doping strategy by incorporating light-weight boron into the cathode active material lattice to decrease the irreversible oxygen oxidation at high voltages (i.e., >4.0 V vs. Na+/Na). The presence of covalent B–O bonds and the negative charges of the oxygen atoms ensures a robust ligand framework for the NaLi1/9Ni2/9Fe2/9Mn4/9O2 cathode material while mitigating the excessive oxidation of oxygen for charge compensation and avoiding irreversible structural changes during cell operation. The B-doped cathode material promotes reversible transition metal redox reaction enabling a room-temperature capacity of 160.5 mAh g−1 at 25 mA g−1 and capacity retention of 82.8% after 200 cycles at 250 mA g−1. A 71.28 mAh single-coated lab-scale Na-ion pouch cell comprising a pre-sodiated hard carbon-based anode and B-doped cathode material is also reported as proof of concept., The irreversible oxygen redox reaction during charging to the high-voltage region causes cathode structural degradation and Na-ion cell capacity fading. Here, the authors report a B-doped cathode active material to mitigate the irreversible oxygen oxidation and increase the cell capacity.

The O3-type layered oxide cathodes for sodium-ion batteries (SIBs) are considered as one of the most promising systems to fully meet the requirement for future practical application. However, fatal issues in several respects such as poor air stability, irreversible complex multiphase evolution, inferior cycling lifespan, and poor industrial feasibility are restricting their commercialization development. Here, a stable Co-free O3-type NaNi 0.4 Cu 0.05 Mg 0.05 Mn 0.4 Ti 0.1 O 2 cathode material with large-scale production could solve these problems for practical SIBs. Owing to the synergetic contribution of the multielement chemical substitution strategy, this novel cathode not only shows excellent air stability and thermal stability as well as a simple phase-transition process but also delivers outstanding battery performance in half-cell and full-cell systems. Meanwhile, various advanced characterization techniques are utilized to accurately decipher the crystalline formation process, atomic arrangement, structural evolution, and inherent effect mechanisms. Surprisingly, apart from restraining the unfavorable multiphase transformation and enhancing air stability, the accurate multielement chemical substitution engineering also shows a pinning effect to alleviate the lattice strains for the high structural reversibility and enlarges the interlayer spacing reasonably to enhance Na + diffusion, resulting in excellent comprehensive performance. Overall, this study explores the fundamental scientific understandings of multielement chemical substitution strategy and opens up a new field for increasing the practicality to commercialization.

Developing high-voltage layered cathodes for sodium-ion batteries (SIBs) has always been a severe challenge. Herein, a new family of honeycomb-layered Na3Ni1.5M0.5BiO6 (M = Ni, Cu, Mg, Zn) with a monoclinic superstructure has been shown to combine good Na+ (de)intercalation activity with a competitive 3.3 V high voltage. By coupling the electrochemical process with ex situ X-ray absorption spectroscopy as well as in situ X-ray diffraction, the charge compensation mechanism and structural evolution of these new cathodes are clearly investigated. Interestingly, both Ni2+/Ni3+ and Cu2+/Cu3+ participate in the redox reaction upon cycling, and the succession of single-phase, two-phase, or three-phase regions upon Na+ extraction/insertion were identified with rather good accuracy. This research strategy could provide insights into the structure–function–property relationships on a new series of honeycomb-ordered materials with the general formula Na3Ni1.5M0.5BiO6 and also serve as a bridge to guide future desig...

Low-cost and stable sodium-layered oxides (such as P2- and O3-phases) are suggested as highly promising cathode materials for Na-ion batteries (NIBs). Biphasic hybridization, mainly involving P2/O3 and P2/P3 biphases, is typically used to boost their electrochemical performances. Herein, a P3/O3 intergrown layered oxide (Na2/3 Ni1/3 Mn1/3 Ti1/3 O2 ) as high-rate and long-life cathode for NIBs via tuning the amounts of Ti substitution in Na2/3 Ni1/3 Mn2/3-x Tix O2 (x = 0, 1/6, 1/3, 2/3) is demonstrated. The X-ray diffraction (XRD) Rietveld refinement and aberration-corrected scanning transmission electron microscopy show the co-existence of P3 and O3 phases, and density functional theory calculation corroborates the appearance of the anomalous O3 phase at the Ti substitution amount of 1/3. The P3/O3 biphasic cathode delivers an unexpected rate capability (≈88.7% of the initial capacity at a high rate of 5 C) and cycling stability (≈68.7% capacity retention after 2000 cycles at 1 C), superior to those of the sing phases P3-Na2/3 Ni1/3 Mn2/3 O2 , P3-Na2/3 Ni1/3 Mn1/2 Ti1/6 O2 , and O3-Na2/3 Ni1/3 Ti2/3 O2 . The highly reversible structural evolution of the P3/O3 integrated cathode observed by ex situ XRD, ex situ X-ray absorption spectra, and the rapid Na+ diffusion kinetics, underpin the enhancement. These results show the important role of P3/O3 biphasic hybridization in designing and engineering layered oxide cathodes for NIBs.

Sodium-ion batteries have gained much attention for their potential application in large-scale stationary energy storage due to the low cost and abundant sodium sources in the earth. However, the electrochemical performance of sodium-ion full cells (SIFCs) suffers severely from the irreversible consumption of sodium ions of cathode during the solid electrolyte interphase (SEI) formation of hard carbon anode. Here, a high-efficiency cathode sodiation compensation reagent, sodium oxalate (Na2 C2 O4 ), which possesses both a high theoretical capacity of 400 mA h g-1 and a capacity utilization as high as 99%, is proposed. The implementation of Na2 C2 O4 as sacrificial sodium species is successfully realized by decreasing its oxidation potential from 4.41 to 3.97 V through tuning conductive additives with different physicochemical features, and the corresponding mechanism of oxidation potential manipulation is analyzed. Electrochemical results show that in the full cell based on a hard carbon anode and a P2-Na2/3 Ni1/3 Mn1/3 Ti1/3 O2 cathode with Na2 C2 O4 as a sodium reservoir to compensate for sodium loss during SEI formation, the capacity retention is increased from 63% to 85% after 200 cycles and the energy density is improved from 129.2 to 172.6 W h kg-1 . This work can provide a new avenue for accelerating the development of SIFCs.

Envelope analysis is the popular fault diagnosis method of rolling bearing. It can diagnosis rolling bearing fault, such as inner race fault and outer race fault. The traditional envelope analysis is set up on the measured acceleration signal. It is influenced by noise seriously, especially in bearing early fault stage. Research shows that the amplitude modulation phenomenon can be enlarged if the envelope analysis is done for the auto-correlation signal. Vibration test was done for a driving motor with fault rolling bearing. Factors influencing the effect of envelope analysis were analyzed.

According to bent position and size on two HP-IP bent rotor,and combined with maintenance schedule,this paper puts forward two vibration control methods of low speed dynamic balance on site and high speed dynamic balance after turning.For the bent position in the turbine middle,on the basis of mode decomposition in bent rotor,the research show that balance weight according to a scale in the both ends and middle mainly of the turbine can achieve good results.

The supercritical turbine, changed low pressure rotor’s blade in site, bear vibration over-proof seriously because of unbalance, reached rated speed after dynamic balance in site. The vibration of low pressure Ⅱshaft’s bear was still over-proof. And the bear vibration phase was anti-phase with the shaft vibration not only anti-phase but also in-phase. It was found that the bear vibration was highly related with the anti-phase component of shaft vibration after running date analysis. And the bear vibration was reduced obviously after the anti-phase component of shaft’s residual unbalanced mass reduced by dynamic balance in site.

The aim of this study was to examine the effects of a 12-week home-based exercise program on physical function, psychological dimensions, and health-related quality of life for patients with chronic kidney disease. Ninety eligible patients were enrolled and randomly separated into the exercise group and the control group from November 2015 to May 2016. The exercise group received an individualized exercise program while the control group received only usual care and continued primary lifestyle. Physical function was measured using 6-minute walk test and 10 repetitions of the sit-to-stand test while psychological dimensions were assessed by the Hospital Anxiety and Depression scale and the Self-Efficacy for Exercise scale. Quality of life was evaluated by a disease-specific instrument, the Kidney Disease Quality of Life scale. The differences between the exercise group and the control group were statistically significant for 6-minute walk distance, the time to complete 10 repetitions of the sit-to-stand test, self-efficacy for exercise, anxiety and depression, and all domains of health-related quality of life after a 12-week exercise. This study suggests that home-based individualized exercise program is an effective and feasible way of improving physical function, psychological stress, and health-related quality of life for early stage of chronic kidney disease patients.

A frequency reconfigurable Unequal Wilkinson power divider is proposed. The divider's operating frequency can be reconfigured within a wide band. Reconfiguration is achieved because of two simple π-shaped circuits with varactors, which are inserted into the two impedance transformers of a conventional unequal Wilkinson power divider. Equivalent impedance of the two transformers are nearly unchanged while their phases are reconfigured by varying the varactors' biasing voltages. Operating frequency is changed continuously by tuning varactors' biasing voltages. Simulation results show that tuning bandwidth is over 73% regarding to the lowest operating frequency. Other preferred properties, such as good matching, small insertion loss, and miniaturized size are also achieved.

Based on the communicating vessel principle, we present a new instrument for the measurement of bearing elevation change. A number of cups are attached to the bearings. They are linked with pipes and joints together to constitute a measurement network. Special features of the instrument to make the measurement easily and reliable, such as cup design, are presented. The instrument is used to monitor and analyze the elevation change of a 1000MW turbo-generator during the vacuum setup process. We find that the influence of vacuum on the elevation of bearing located on the exhaust cylinder is large. The maximum value is 1.8mm when vacuum changes from 0KPa to 90KPa. It causes unload of bearing #5~#8 and overload of bearing #2~#4. Adjustment project is given in the last of the paper to solve rub and pad fragment fault occurred in the unit. It is verified that the elevation adjustment for such kind of fault is valuable.

Two turbine generator units with unstable vibration faults caused by unreasonable bearing elevation distribution are presented. Using the communicating vessel principle, elevation change among bearings with condenser vacuum and power are measured and analyzed. We found that elevation of bearings on low pressure cylinder in high vacuum state is the lowest among bearings. Shaft alignment in the cold state is not unreasonable. We pre-compensated and adjusted bearing elevation in the cold state on the base of the measured bearing elevation data. Vibration faults of two units were solved successfully. Vibration phenomenon, bearing elevation change monitoring data and fault troubleshooting method are presented. It is verified that bearing elevation pre-compensation method for solving such kind of faults is valuable.