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A fast, portable, nondestructive, and simple‐to‐operate method for determination of water cane shoot quality via an electronic nose (E‐nose) system is presented. The responses of E‐nose sensors to cane shoot samples during storage time are measured. Considering that one of the most common problems with fresh aquatic vegetables is the nearly negligible change in volatile organic compounds, a novel swarm clustering based on particle swarm optimization (SWC) algorithm is proposed to extract the effective features of the sensors responses. In SWC, the number of clusters is automatically estimated based on the neighborhood radius of the particles, which reduces the difficulty in determining the number of cluster. Traditional clustering algorithms, such as K‐means clustering (KMC) and hierarchical clustering analysis (HCA), are used for the purposes of comparison, and the changes in quality of cane shoot samples are quantitatively determined according to the hardness and pH. The results suggest that the E‐nose‐based SWC methodology is capable of accurately classifying the cane shoots freshness during the 20‐day storage time, which is much better than that of the comparative KMC and HCA methods. Additionally，quantitative analysis of the sensory evaluation, hardness, and pH is shown to have good agreement with the E‐nose system analysis results. Validation experiments show that unknown samples are successfully grouped into several different categories with a high correlation (R2 =.982) between unknown and known samples, demonstrating the potential use of E‐nose system to predict the freshness of the cane shoots. [ABSTRACT FROM AUTHOR]

Fe doping is widely used to improve the electrochemical performance of LiMnPO4 by “implanting” the merits of high rate capability and long cycle life of LiFePO4 into LiMnPO4. Nevertheless, great challenges still remain to obtain high-performance LiFexMn1−xPO4 at a low x value. In this work, we synthesized ultrathin LiFexMn1−xPO4 (x≤ 0.15) nanoplates by a facile, controllable method. The plate-like LiFexMn1−xPO4 with a small lateral size (40–100 nm) and thickness (10–20 nm) exhibits high electrochemical activity, excellent rate capability and superior cycling stability after carbon coating. At a rate as high as 50C (8.5 A g−1), the LiFe0.15Mn0.85PO4/C composite can still yield a high discharge capacity of 96.2 mA h g−1 where the discharge process can be completed in only 40 s. LiFe0.15Mn0.85PO4/C can sustain a long-term cycling up to 1000 cycles at 10C with a capacity retention close to 70%. The fast and stable cycling ability of LiFexMn1−xPO4 makes it promising for applications in electric vehicles and hybrid electric vehicles. [ABSTRACT FROM AUTHOR]

Na-ion Batteries have been considered as promising alternatives to Li-ion batteries due to the natural abundance of sodium resources. Searching for high-performance anode materials currently becomes a hot topic and also a great challenge for developing Na-ion batteries. In this work, a novel hybrid anode is synthesized consisting of ultrafine, few-layered SnS2 anchored on few-layered reduced graphene oxide (rGO) by a facile solvothermal route. The SnS2/rGO hybrid exhibits a high capacity, ultralong cycle life, and superior rate capability. The hybrid can deliver a high charge capacity of 649 mAh g−1 at 100 mA g−1. At 800 mA g−1 (1.8 C), it can yield an initial charge capacity of 469 mAh g−1, which can be maintained at 89% and 61%, respectively, after 400 and 1000 cycles. The hybrid can also sustain a current density up to 12.8 A g−1 (≈28 C) where the charge process can be completed in only 1.3 min while still delivering a charge capacity of 337 mAh g−1. The fast and stable Na-storage ability of SnS2/rGO makes it a promising anode for Na-ion batteries. [ABSTRACT FROM AUTHOR]

Despite the recent advancements in Li-O(2) (or Li-air) batteries, great challenges still remain to realize high-rate, long-term cycling. In this work, a binder-free, nanostructured RuO(2)/MnO(2) catalytic cathode was designed to realize the operation of Li-O(2) batteries at high rates. At a current density as high as 3200 mA g(-1) (or ∼1.3 mA cm(-2)), the RuO(2)/MnO(2) catalyzed Li-O(2) batteries with LiI can sustain stable cycling of 170 and 800 times at limited capacities of 1000 and 500 mA h g(-1), respectively, with low charge cutoff potentials of ∼4.0 and <3.8 V, respectively. The underlying mechanism of the high catalytic performance of MnO(2)/RuO(2) was also clarified in this work. It was found that with the catalytic effect of RuO(2), Li(2)O(2) can crystallize into a thin-sheet form and realize a conformal growth on sheet-like δ-MnO(2) at a current density up to 3200 mA g(-1), constructing a sheet-on-sheet structure. This crystallization behavior of Li(2)O(2) not only defers the electrode passivation upon discharge but also renders easy decomposition of Li(2)O(2) upon charge, leading to low polarizations and reduced side reactions. This work provides a unique design of catalytic cathodes capable of controlling Li(2)O(2) growth and sheds light on the design of high-rate, long-life Li-O(2) batteries with potential applications in electric vehicles.

Conductivity detection was employed to detect the enantiomers of bupivacaine hydrochloride (Bup), which were separated by high performance capillary electrophoresis. A computer-aided technique was used to calculate the binding energies, and the interaction between Bup enantiomers and cyclodextrins (CDs) is preliminarily discussed. Factors affecting the separation efficiency such as the types and concentration of chiral selectors, running buffer, pH value, separation voltage and capillary inside diameter and length were studied. Under optimized conditions, a baseline separation of Bup enantiomers was achieved in less than 15 min in 4mM NH4Ac-NaAc-HAc (pH 4.00) -0.48mM sulfobutyl ether-beta-cyclodextrin running buffer at a separation voltage of 12 kV. The lowest detectable concentration was 0.052 microg/mL. The proposed method was applied to chiral separation of Bup enantiomers in rabbit serum and pharmaceutical injections.