Nuciferine modulates the gut microbiota and prevents obesity in high-fat diet-fed rats

Wang Yueping,Yao Weifan,Li Bo,Qian Shiyun,Wei Binbin,Gong Shiqiang,Wang Jing,Liu Mingyan,Wei Minjie 생화학분자생물학회 2020 Experimental and molecular medicine Vol.52 No.-

Gut microbiota dysbiosis has a significant role in the pathogenesis of metabolic diseases, including obesity. Nuciferine (NUC) is a main bioactive component in the lotus leaf that has been used as food in China since ancient times. Here, we examined whether the anti-obesity effects of NUC are related to modulations in the gut microbiota. Using an obese rat model fed a HFD for 8 weeks, we show that NUC supplementation of HFD rats prevents weight gain, reduces fat accumulation, and ameliorates lipid metabolic disorders. Furthermore, 16S rRNA gene sequencing of the fecal microbiota suggested that NUC changed the diversity and composition of the gut microbiota in HFD-fed rats. In particular, NUC decreased the ratio of the phyla Firmicutes/Bacteroidetes, the relative abundance of the LPS-producing genus Desulfovibrio and bacteria involved in lipid metabolism, whereas it increased the relative abundance of SCFA-producing bacteria in HFD-fed rats. Predicted functional analysis of microbial communities showed that NUC modified genes involved in LPS biosynthesis and lipid metabolism. In addition, serum metabolomics analysis revealed that NUC effectively improved HFD-induced disorders of endogenous metabolism, especially lipid metabolism. Notably, NUC promoted SCFA production and enhanced intestinal integrity, leading to lower blood endotoxemia to reduce inflammation in HFD-fed rats. Together, the anti-obesity effects of NUC may be related to modulations in the composition and potential function of gut microbiota, improvement in intestinal barrier integrity and prevention of chronic low-grade inflammation. This research may provide support for the application of NUC in the prevention and treatment of obesity.

Structure and Electrical Performance of Na₂C₆O₆ under High Pressure

Wang, Xuan,Zhang, Peijie,Tang, Xingyu,Guan, Junjie,Lin, Xiaohuan,Wang, Yajie,Dong, Xiao,Yue, Binbin,Yan, Jinyuan,Li, Kuo,Zheng, Haiyan,Mao, Ho-kwang American Chemical Society 2019 The Journal of Physical Chemistry Part C Vol. No.

<P>Sodium rhodizonate (Na<SUB>2</SUB>C<SUB>6</SUB>O<SUB>6</SUB>) has very high theoretical capacity as a positive electrode material of sodium-ion batteries, but it still has problems such as low actual capacity and poor electronic/ionic conductivity. In order to improve its conductivity, we investigated its structure and electrical properties under high pressure. By performing in situ X-ray diffraction, Raman, infrared absorption, and alternating current impedance spectroscopy in the range of 0-30 GPa at room temperature, we observed a phase transition at ∼11 GPa, with the conductivity increasing by an order of magnitude. Above ∼20 GPa, Na<SUB>2</SUB>C<SUB>6</SUB>O<SUB>6</SUB> gradually amorphized. During the decompression process, the pressure regulation of the structure and properties of the material are reversible. Our study shows that applying external pressure is an effective tool to improve the conductivity of molecular battery materials. The investigation will help to obtain next-generation electrode materials.</P> [FIG OMISSION]</BR>

Simple and green fabrication of a biomass-derived N and O self-doped hierarchical porous carbon via a self-activation route for supercapacitor application

Yang Binbin,Zhang Deyi,He Jingjing,Wang Yuling,Wang Kunjie,Li Hongxia,Wang Yi,Miao Lei,Ren Ruiye,Xie Mei 한국탄소학회 2020 Carbon Letters Vol.30 No.6

To meet the increased performance and cost requirements of commercial supercapacitor, a N and O self-doped hierarchical porous carbon is fabricated via a green and simple self-activation route utilizing leaves of wild hollyhock as raw materials. Comparing to commercial activated carbon, the reported material exhibits some marked merits, such as simple and green fabrication process, low cost, and superior capacitance performance. The specifc surface area of the obtained N and O co�doped hierarchical porous carbon arrives 954 m2 g−1, and the content of the self-doped nitrogen and oxygen reaches 2.64 at.% and 7.38 at.%, respectively. The specifc capacitance of the obtained material reaches 226 F g−1 while the specifc capacitance of the symmetric supercapacitor arrives 47.3 F g−1. Meanwhile, more than 90.3% of initial specifc capacitance is kept under a current density of 20 A g−1, and no arresting degradation is observed for capacitance after 5000 times cycle, perfectly demonstrating the excellent cycle and rate capability of the obtained material. The obtained N and O co-doped hierarchical porous carbon are expected to be an ideal substitution for commercial activated carbon.

Modulation, Harmonic Analysis, and Balancing Control for a New Modular Multilevel Converter

Binbin Li,Yi Zhang,Gaolin Wang,Dianguo Xu 전력전자학회 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.1

The modular multilevel converter (MMC) has been receiving increased attentions in recent years. The new modular multilevel converter is a derivative topology from the traditional MMC in which the number of sub-modules (SMs) necessitated by each phase can be reduced by one. This paper presents a phase-shifted carrier pulse-width modulation (PSC-PWM) for the new MMC with an optimal phase-shifted angle to suppress the harmonics of the output voltage. Further, the harmonic features when the capacitor voltage of the middle SM is selected as two different values are also investigated. Moreover, in order to avoid introducing an unnecessary dc offset current at the ac terminals of the new MMC, a novel capacitor voltage balancing scheme is proposed by adjusting the amplitude of the reference signals rather than the offset. Finally, the validity and effectiveness of the proposed modulation and balancing schemes have been verified by experimental results based on a three-phase prototype of the new MMC.

Intermediate-layer strengthened superhydrophobic coating with stable corrosion resistance, delayed icing and long-term weatherability

Binbin Zhang,Guang Yang,Xiaoqiang Fan,Xiutong Wang,Baorong Hou 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.127 No.-

Improving the mechanical stability and anti-corrosion durability of superhydrophobic material remains agreat challenge that has not been solved. In this paper, we designed and prepared two types of superhydrophobiccoatings using PTFE nanoparticles and waterborne epoxy resin, viz. superhydrophobicPTFE@epoxy single layer coating and superhydrophobic Epoxy + PTFE@epoxy double layer coating. Itwas found that the mechanical stability and interfacial bonding of the superhydrophobic composite coatingswere further improved by introducing an epoxy resin intermediate layer. The superhydrophobicEpoxy + PTFE@epoxy double layer coating maintained excellent non-wetting superhydrophobicity evenafter 150 sandpaper abrasion and 160 tape-peeling cycles. The electrochemical testing results showedthat the Rct and low-frequency modulus values of the superhydrophobic double layer coating improvedby 7–8 orders of magnitude compared with the bare Q235 carbon steel substrate, demonstrating excellentcorrosion resistance. In addition, the coating maintains good corrosion protection after 60 days ofoutdoor atmospheric exposure and 30 days of neutral salt spray acceleration tests, indicating superiorweathering resistance and long-term anti-corrosion properties. The coating also features delayed icing,self-cleaning, anti-fouling, chemical stability, and high substrate applicability, which provides longlastingmultifunctional superhydrophobic materials with comprehensive functions.

Analysis of the Operating Principle and Parameter Design for the Modular Multilevel DC/DC Converter

Binbin Li,Shaolei Shi,Yibo Zhang,Rongfeng Yang,Gaolin Wang,Dianguo Xu 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6

The modular multilevel converter (MMC) has become more and more attractive in the field of high-voltage high-power dc/ac power conversions. In the very recent years, the dc/dc modular multilevel converter is proposed intended for high-voltage dc/dc applications, such as the solid-state transformers and future dc-grid networks, which is extended from the traditional MMC. However, it remains unknown how to optimize the operation of this dc/dc modular multilevel converter and how to dimension the parameters of the elements in it. In this paper, a detailed analysis is performed to indentify the operating principle of the dc/dc modular multilevel converter. Using these analyses, the selection rules and parameter design method of the components are given to maximize the utilization ratio, improve the power density, and increase efficiency. Finally, the validity and effectiveness of this paper are verified by simulation results.

An IGBT Open-Circuit Fault Detection Method for Modular Multilevel Converters

Binbin Li,Yi Zhang,Rongfeng Yang,Gaolin Wang,Dianguo Xu 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6

Recently, the modular multilevel converter (MMC) has attracted increasing attentions due to its distinctive features, especially in the application of HVDC power transmission. One of the most significant characteristic of MMC is that it is composed of identical low-voltage submodules (SMs). As a result, the low-voltage IGBTs can be employed in each SM as the main power switch. However, since an MMC station usually contains hundreds of SMs, the IGBT becomes the most fragile component. In this paper, the failure characteristics of the IGBT open-circuit fault in a SM are firstly analyzed. Then, an observer-based IGBT open-circuit detection method is proposed, which can accurately detect the fault by comparing the estimated values with the actual sampled values. Finally, the validity and effectiveness of the proposed fault detection method are demonstrated by experimental results based on a single-phase MMC prototype in the laboratory.

Analysis of flow transition and separation on oscillating airfoil by pressure signature

Binbin Wei,Yongwei Gao,Long Wang,Dong Li 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.1

To have a better understanding of the unsteady aerodynamic characteristics of the airfoil which play important roles in wind turbine blade design, we investigated the boundary layer transition and separation on oscillating airfoil S809 using pressure signature captured in wind tunnel testing. The developed data processing technique of "sliding window" was applied to get useful transition and separation information. Meanwhile, the hysteresis effects of oscillation frequency on transition and separation were studied. It is found that (1) the root mean square (RMS) of pressure signature can indicate the transition and separation with the dimensionless window width of `m = 0.0015; (2) the transitional attack of angle in up stroke is larger than that in down stroke at the state of the relative chord length of x/c ≥ 0.14, while the situation is opposite at the state of the relative chord length of x/c ≤ 0.14; (3) the flow separation is advanced and the reattachment is delayed with the increase of the oscillation frequency, which results in a greater hysteresis effect. The sliding window technique, whose parameters were determined in this paper, is effective for detecting boundary layer transition and separation from pressure signature.

A Precise Stability Criterion for Power Hardware-in-the-loop Simulation System

Shengbo Wang,Binbin Li,Zigao Xu,Xiaodong Zhao,Dianguo Xu 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

Power hardware in the loop (PHIL) simulation is an attractive option for power system testing, as it combines the benefits of real-time digital simulation and physical experiments. In view of the fact that only systems with pure resistance have been considered in previous literatures, this paper presents a systematic and comprehensive approach to evaluating stability of different types of impedance. A rigorous stability criterion of a PHIL system based on the ideal transformer interface model which utilizes Nyquist stability criterion is introduced in this paper. Phase lag caused by delay time in the PHIL system is considered to be the essential cause of instability and in terms of Nyquist criterion, relative positions of the starting and ending points of the Nyquist curve completely determine stability conditions. Effectiveness of the proposed stability criterion is verified by experimental results conducted by RT-LAB.

Modulation, Harmonic Analysis, and Balancing Control for a New Modular Multilevel Converter

Li, Binbin,Zhang, Yi,Wang, Gaolin,Xu, Dianguo The Korean Institute of Power Electronics 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.1

The modular multilevel converter (MMC) has been receiving increased attentions in recent years. The new modular multilevel converter is a derivative topology from the traditional MMC in which the number of sub-modules (SMs) necessitated by each phase can be reduced by one. This paper presents a phase-shifted carrier pulse-width modulation (PSC-PWM) for the new MMC with an optimal phase-shifted angle to suppress the harmonics of the output voltage. Further, the harmonic features when the capacitor voltage of the middle SM is selected as two different values are also investigated. Moreover, in order to avoid introducing an unnecessary dc offset current at the ac terminals of the new MMC, a novel capacitor voltage balancing scheme is proposed by adjusting the amplitude of the reference signals rather than the offset. Finally, the validity and effectiveness of the proposed modulation and balancing schemes have been verified by experimental results based on a three-phase prototype of the new MMC.