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Owing to the significance and requirement of renewable energy resources, in this study, ellipsoidal porous carbons with yolk-shell structures assembled using MnO and Ganoderma lucidum spores are fabricated for application prospects in energy storage systems; they exhibit excellent ion transfer capability. However, the surface of carbon nanomaterials is naturally hydrophobic, resulting in a lower energy density. Herein, heteroatom doping and O2/Ar plasma surface treatment are utilized to obtain high specific capacitance and fast charging. Surface functionalization increases the surface roughness and oxygen-containing functional groups of the material. The specific capacitance of the best sample MnO/GSC-O–NS–10 was 568.9 F g−1 when the current density was 0.5 A g−1. The performance test was carried out for 10000 cycles at a current density of 10 A g−1 and the capacitance retention rate was 75.11%. The assembled two-electrode capacitor exhibited a specific capacitance of 240.4 F g−1 and an energy density of 33.4 Wh kg−1 at a power density of 407 W kg −1. These findings provide sufficient theoretical guidance for the development of high-performance supercapacitors.

Phytohormones are interrelated by synergistic or antagonistic crosstalk and play important roles in the regulation of plant growth and development. In order to understand the interaction between phytohormones in the plant physiological network, it is necessary to determine trace levels of multiple phytohormones simultaneously in a complex matrix. Here, we synthesized ionic liquids containing different functional groups and modified the surface of carbon fibers with them. Based on these carbon fibers-ionic liquid (CFs-IL) materials, a solid phase microextraction method was developed to enable the simultaneous extraction of phytohormones. The adsorption specificity of multiple phytohormones was studied by identifying the hydrophobic, electrostatic, and π-π interactions, as well as hydrogen bonds, which favor simultaneous extraction of the relevant acidic, alkaline and neutral phytohormones by improving compatibility. The proposed method, coupled with liquid chromatography-tandem mass spectrometry, was applied to the simultaneous determination of 13 acidic, alkaline and neutral phytohormones in tomato. The limits of quantification were found to be in the range of 0.32–54.05 ng mL−1 and 4.6–185.8 pg mL−1, respectively, when measured by QQQ and Q-TOF. All of the relative recoveries were in the range of 94.40–113.37% with RSDs ≤15.36% (n = 3) for spiked tomato samples. This method is expected to be widely applied to multiple phytohormones analysis for in-depth researches concerning the physiological networks of plants.

This study investigated the effect of lactic acid bacteria (LAB) fermentation on the chemical profile of autoclaved broccoli puree, using 7 broccoli-derived LAB isolates (named F1-F5, BF1 and BF2). The total concentrations of glucosinolates (glucoiberin, progoitrin and glucoraphanin) and 10 major phenolics significantly increased from trace level and 289 μg total phenolics/g dry weight (DW) respectively in autoclaved broccoli to 55 to ∼359 μg/g DW and 903 to ∼3105 μg/g DW respectively in LAB fermented broccoli puree. Differential impacts of LAB isolates on the chemical composition of autoclaved broccoli were observed, with the major differences being the significant increase in phloretic acid after fermentation by F1-F5 and an elevated glucoraphanin level in ferments by F1 and BF2. LAB fermentation is a promising way to increase the content of glucosinolates and polyphenolic compounds in broccoli, making the ferments attractive for use as functional ingredients or as a whole functional food.

To resolve socioeconomic and environmental issues caused by vehicular emissions, the Chinese government has developed a series of policies for promoting clean energy vehicles (CEVs), which can be powered by electricity, gas, ethanol or methanol. Effective implementation of these policies requires a comprehensive evaluation of CEVs. Decision-makers need to take into account multiple criteria such as energy performance, energy cost, vehicular emission, market acceptance and energy security. This paper proposes a decision support model, which applies multi-criteria analysis to prioritize CEVs existing and to be launched on the Chinese market. Government officials, academic researchers and industrial executives are interviewed to select and rank criteria for optimizing decision-making using the Analytic Hierarchy Process and the VIKOR optimization techniques. Thirty-five experts have been interviewed for prioritizing four categories of CEVs including electric, gas, methanol and ethanol vehicles from both the national and provincial perspectives. Results demonstrate that electric vehicles represent the highest ranking, followed by gas, methanol and ethanol vehicles. The proposed model has been validated using statistical data and existing government policies. The proposed multi-criteria analysis can be used for advising decision-makers in the area of clean energy vehicles.

New coated carbon fibers (CCFs) have been synthesized, characterized and used as solid phase microextraction (SPME) matrix for the analysis of phytohormones (jasmonic acid, indole-3-acetic acid, and abscisic acid) in wheat samples. The SPME device, realized inserting CCFs in a pencil-type device, when coupled with gas chromatography-mass spectrometry, provides in few steps high recovery values (79-112%), fast on-fiber derivatization (30 s), good method reproducibility (RSD 20%), low detection limits (0.5-2.1 ng g

LCL filter is an important component in the grid-connected inverters. The parameters of LCL filter have a strong influence on the output current distortion of inverters. For three-level inverter system, a parameters design method is proposed in this paper based on genetic algorithm optimization of output current total harmonic distortion (THD). By deducing the transfer function of the filter, output current THD is calculated through double Fourier analysis. Then an adaptive immune genetic algorithm is designed to solve the objective parameters optimization issue under constraint condition. With harmonics attenuation in both fundamental band and carrier band taken into account, the filter parameters are optimized scientifically by the global search algorithm, which contains punishment mechanism, adaptive parameters and the mechanism of immune algorithm. The feasibility of the proposed method is verified by conducting simulation and experiment.

The mathematical relation between the sub-module capacitance and the DC system operation characteristics has been analyzed from 4 aspects including the steady energy exchange process of modular multilevel flexible HVDC system, the dynamic response characteristics of active power control, the transient energy exchange process and the bridge arm protection requirement when the DC bipolar short circuit fault. A fault diagnosis and error prevention strategy for the multilevel sub-module system based on the higher order naive Bayes model (HONBM) is proposed. Firstly, analyze the model structure of the multilevel transmission sub-module, and give the Bayes model structure for the fault analysis of the electrical components in the multilevel transmission sub-module model. Then, based on the theoretical analysis results, the selection principle and the calculation method of the modularized multilevel sub-module capacitance are given. The sub-module capacitance is usually calculated according to the requirements of the steady-state sub-module voltage fluctuation and the dynamic response characteristics of the active power control, and then the calibration is made based on the transient sub-module voltage fluctuation and the bridge arm protection requirements.