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Current East Asian winter monsoon (EAWM) indices effectively depict the associated high‐ and low‐latitude atmospheric circulations. However, the spatial dynamics of the winter coldness within the monsoon domain are not well adequately represented by EAWM indices. We introduce a novel approach to classify winter temperatures based on both their co‐variability and their mean values. We classified the EAWM domain into three distinct modes: northern (ranging from −27°C to −15°C), central (−14°C to 5°C), and southern (6°C to 27°C). The northern mode, characterised by intense coldness, correlates with a strengthened westerlies that traps Arctic cold air masses during the positive phase of the Arctic Oscillation (AO). In contrast, the southern mode is primarily influenced by low‐latitude oceanic and atmospheric patterns, particularly for near‐coast areas. The central mode, representing an interplay of both high and low‐latitude processes, encapsulates the comprehensive characteristics of the EAWM. Our analysis reveals a notable shift in the relationships among the northern, central, and southern modes around 1990. Prior to this year, the EAWM was predominantly influenced by northern atmospheric patterns, while there is a discernible increase in the influence of low‐latitude drivers afterwards. This shift may be linked to the significant warming in the western Pacific and Indian Oceans, underscoring the heightened role of low‐latitude drivers on the EAWM. [ABSTRACT FROM AUTHOR]

To study the effect of fine particle size and volume concentration on the performance of solid-liquid two-phase centrifugal pump, the mixture multiphase flow model, RNG k-ε turbulence model, and SIMPLEC algorithm were used to simulate the two-phase flow of the centrifugal pump. The effects of particle size and volume concentration on internal pressure distribution, solid volume distribution, and external characteristics were analyzed. The results show that under the design discharge conditions, with the increase of particle size and volume concentration, the internal pressure of the flow field will decrease, and the volume fraction of solid phase in the impeller passage will also decrease as a whole. The solid particles gradually migrate from the suction surface to the pressure surface, and the particles in the volute channel are mainly concentrated in the flow channel near the outlet side of the volute. With the increase of particle size and volume concentration, the negative pressure value at the inlet of centrifugal pump increases, the total pressure difference at the inlet and outlet decreases, and the head and efficiency decrease accordingly. [ABSTRACT FROM AUTHOR]

Series Li1.2Ni0.2Mn0.6O2 (LNMO) cathode materials have been synthesized by an improved one-step solvothermal method. Structural characterization reveals that all samples are composed of layered and spinel phases and the spinel phase content can be easily tuned by Na-doping or reducing lithium in the LNMO materials. The spinel phase content increases from 2.6% for the x = 0.02 Na-doped sample to 9.2% for the deficient lithium sample. Electrochemical performance measurement shows that the electrochemical performance of the series samples is closely related to the spinel phase content. The deficient lithium sample with the largest spinel phase content has the most excellent cyclic and rate performance. The deficient lithium sample displays a high discharge capacity of 118.9 mAh g−1 at 5 C rate and much more stable capacity retention of 89.4% after 50 cycles at 0.1 C rate, whereas the corresponding values are 66.7, 27.4, and 2.7 mAh g−1 at 5 C rate and 69.4, 58.7, and 37.8% at 0.1 C rate for the Na-doped samples with x = 0, 0.01, and 0.02. The excellent cyclic and rate performance of the electrodes with higher spinel phase content originated from more 3D Li-ion diffusion channels in spinel framework and the relatively stable layered structure improved by an appropriate spinel phase integration. [ABSTRACT FROM AUTHOR]

An efficient convolution kernel could transform images into more expressive representations, which usually determines the quality of image classification models. Algorithms in the field of hyper-parameter optimization and neural architecture search could be applied to mining optimal kernels, while hyper-parameter optimization algorithms always require multiple training sessions to evaluate hyper-parameter configurations, resulting in a high time consumption. Recent gradient-based architecture search algorithms could deal with such problems within a single training session. However, there are currently no gradient-based NAS algorithms that could be used to efficiently optimize convolution kernels. This paper proposes a novel gradient-based algorithm, SoftStep, which could precisely and efficiently fine-tune the hyper-parameters of kernels. The proposed SoftStep is applied for the optimization of the convolution kernel's key hyper-parameters and generalized to more hyper-parameters in deep learning. In experiments, architecture search tasks on multiple challenging datasets are compared to various state-of-art hyper-parameter optimization and architecture search algorithms. The reported results show that SoftStep could mine optimal kernels far more efficiently than other SOTA methods. [ABSTRACT FROM AUTHOR]

Hollow MnO microcubes with edge length about 8 μm are prepared by a thermal decomposition process of MnCO 3 precursor, which are obtained via a simple hydrothermal method. The morphologies of the final products are controlled by adjusting the amount of urea so as to achieve good electrochemical property. The microcube varies from hollow structure to solid structure and the pore size with the increasing amount of urea. The hollow MnO microcube exhibits a high reversible capability in the first cycle is 901.4 mA h g −1  at 0.1 C, slightly decreases to 722.9 mA h g −1  at 0.5 C in the 4th cycle and rises to 914.6 mA h g −1  at 0.5 C even after 200 cycles. Furthermore, the same porous MnO hollow microcube delivers high rate reversible specific capacities of 339.4 mA h g −1  at 4 C. The excellent performance of hollow MnO microcube can be attributed to its high surface area and stable hollow structure, which facilitates lithium-ion and electron rapid transport while simultaneously accommodating the drastic volumetric change during electrochemical cycling. [ABSTRACT FROM AUTHOR]

Kaempferol, also known as kaempferol-3 or kaempferide, is a flavonoid compound that naturally occurs in tea, as well as numerous common vegetables and fruits, including beans, broccoli, cabbage, gooseberries, grapes, kale, strawberries, tomatoes, citrus fruits, brussel sprouts, apples and grapefruit. The present review mainly summarizes the application of kaempferol in treating diseases and the underlying mechanisms that are currently being studied. Due to its anti-inflammatory properties, it may be used to treat numerous acute and chronic inflammation-induced diseases, including intervertebral disc degeneration and colitis, as well as post-menopausal bone loss and acute lung injury. In addition, it has beneficial effects against cancer, liver injury, obesity and diabetes, inhibits vascular endothelial inflammation, protects the cranial nerve and heart function, and may be used for treating fibroproliferative disorders, including hypertrophic scar. [ABSTRACT FROM AUTHOR]

Na-doped lithium vanadates Li 3− x Na x VO 4 ( x  = 0, 0.03, 0.05, and 0.08) were synthesized as anode materials for lithium-ion batteries by a simple sol-gel method. The structural and morphological characterizations reveal that Na-doping in Li 3 VO 4 leads to slightly expanded lattice and suppressed particle agglomeration with relative uniform morphology and the doped Na + ions distributed uniformly throughout Li 3 VO 4 grains. The Na-doped Li 3 VO 4 electrodes present enhanced cycling stability, better rate performance and lower charge transfer resistance, especially for the Li 2.95 Na 0.05 VO 4 electrode. It delivers the highest initial charge capacity of 523.4 mAh/g at 0.1C in the series electrodes. After 150 cycles at 1C, Li 2.95 Na 0.05 VO 4 electrode maintains a charge capacity of 398.3 mAh/g, which is almost the same with that of the initial one. In addition, Li 2.95 Na 0.05 VO 4 electrode also exhibits a much better rate capability with 364 and 284 mAh/g at 2C and 4C, respectively, superior to that of Li 3 VO 4 . The excellent electrochemical performance of the Na-doped samples is suggested to originate from the much higher lithium diffusion coefficient induced by the expanded lattice, the much smaller polarization and charge transfer resistance. [ABSTRACT FROM AUTHOR]

A series of Ca-doped lithium vanadates Li3− xCa xVO4 ( x=0, 0.01, 0.03, and 0.05) are synthesized successfully through a simple sol-gel method. XRD patterns and energy-dispersive X-ray spectroscopy (EDS) mappings reveal that the doped Ca2+ ions enter into the lattice successfully and are distributed uniformly throughout the Li3VO4 (LVO) grains. XRD spectra and SEM images show that Ca doping can lead to an enlarged lattice and refined Li3VO4 particles. A small quantity of V ions will transfer from V5+ to V4+ in the Ca-doped samples, as demonstrated by the X-ray photoelectron spectroscopy (XPS) analysis, which leads to an increase of an order of magnitude in the electronic conductivity. Improved rate capability and cycling stability are observed for the Ca-doped samples, and Li2.97Ca0.03VO4 exhibits the best electrochemical performance among the studied materials. The initial charge/discharge capacities at 0.1 C increase from 480/645 to 527/702 mA h g−1 as x varies from 0 to 0.03. The charge capacity of Li2.97Ca0.03VO4 at 1 C retains 95.3 % of its initial value after 180 cycles, whereas the capacity retention is only 40 % for the pristine sample. Moreover, Li2.97Ca0.03VO4 maintains a high discharge capacity of 301.7 mA h g−1 at a high discharge rate (4 C), whereas the corresponding value is only 95.2 mA h g−1 for the pristine LVO sample. The enhanced cycling and rate performances are ascribed to the increased lithium ion diffusivity and electrical conductivity induced by Ca doping. [ABSTRACT FROM AUTHOR]