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.

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.

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.

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.

Cost-Effective Fabrication of Biomorphic Mesoporous Ni-NiO Microtube for Pseudocapacitors

Binbin Chang,Hang Yin,Zhengyan Gu,Zhikun Li,Baocheng Yang 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2016 NANO Vol.11 No.11

In this paper, a biomorphic mesoporous Ni-NiO microtube was successfully prepared by a facile and cost-effective synthesis strategy using cotton as a biotemplate. The morphology and textural characterization of as-obtained Ni-NiO materials were analyzed by X-ray diffraction patterns, scanning electron microscopy and nitrogen adsorption–desorption technology. The results suggested the as-prepared Ni-NiO samples owned uniform micro-tubular morphology and prominent mesoporous structure. Meanwhile, the effect of annealing temperature on morphology and porosity of Ni-NiO was also investigated. The optimal sample, Ni-NiO-4, exhibited a uniform microtube morphology with an ideal mesoporous structure of a high surface area (15.8 m2 g-1) and suitable mesopore size (9.28 nm). Furthermore, these as-obtained Ni-NiO materials showed enhanced electrochemical property as electrodes for pseudocapacitors. Especially, the Ni-NiO-4 electrode displayed the outstanding capacitive performance, including a high specific capacitance of 98.7 F g-1 at 0.5 A g-1 and satisfactory rate capacity. More importantly, Ni-NiO-4 electrode owned an excellently long-term cycling stability.

A new cascaded multilevel converter topology with energy exchange unit for STATCOM application

Rongfeng Yang,Yinglin Zhang,Binbin Li,Rong xu,Yong yu,Dianguo Xu 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6

The star-connected H-bridge cascaded converter has the disadvantage of capacitors unbalance especially when the unbalance occurs between phases. This paper analyzed one novel topology with energy exchange unit (EEU) to realize the phase capacitors voltage balance. After analyzing the converter structure and balance operation concept, this paper provided detailed modulation and capacitors balance control, including maintaining the EEU capacitor voltage stable, sharing the energy storage between phases and in same phase. The simulation results demonstrate the correction of the topology and control.

Experimental investigation on the propagation characteristics of pressure oscillation in direct contact condensation with low mass flux steam jet

Qiu, Binbin,Yang, Qingchuan,Yan, Junjie,li, Gen,Revankar, Shripad T. Elsevier 2017 Experimental thermal and fluid science Vol.88 No.-

<P><B>Abstract</B></P> <P>The propagation characteristics of pressure oscillation in direct contact condensation with low mass flux steam jet have been investigated experimentally. Steam is injected into subcooled water at one atmosphere pressure with steam mass flux and water temperature range of 186–272kg/(m<SUP>2</SUP> s) and 293–343K. The pressure oscillation propagates in the form of wave with stable dominant frequency, however the wave intensity attenuates with the increasing distance from the oscillation source. The root mean square of pressure wave <I>p</I> <SUB>rms</SUB> attenuates rapidly with the increasing dimensionless radial distance from the nozzle exit. At about dimensionless radial distance <I>R</I> =100, the <I>p</I> <SUB>rms</SUB> is attenuated by about 90%. Although the dominant frequency of the pressure oscillation is constant during the propagation, after <I>R</I> =100, there will be not enough energy for the pressure oscillation to resonate with relevant equipment. A correlation equation to calculate the root mean square of pressure oscillation along the radial distance is given. The prediction errors are within ±30% compared with the experimental data.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The pressure oscillation propagates in the form of wave. </LI> <LI> In the propagation process, the frequency remains the same but the intensity attenuates. </LI> <LI> A correlation to calculate the <I>p</I> <SUB>rms</SUB> along the radial distance is given. </LI> <LI> At about R=100, the <I>p</I> <SUB>rms</SUB> is attenuated by about 90% and most of the energy is dissipated. </LI> </UL> </P>

Solvent-free aerobic oxidation of ethylbenzene over Mn-containing silylated MgAl layered double hydroxides

Lei Yang,Binbin Fan,Xingyu Cui,Xiufeng Shi,Ruifeng Li 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.21 No.1

A novel method for the preparation of Mn-containing silylated layered double hydroxides (LDHs) ispresented. The method involves functionalizing the calcined MgAl LDH (LDO) with dimethoxydiphenylsilane(DDS), and then treating it in the aqueous solution of KMnO4 under Ar. The prepared Mncontainingsilylated MgAl LDH catalysts have higher Mn amount and more accessible Mn sites than thecorresponding Mn-containing MgAl LDH catalysts, and exhibited much higher catalytic activity in theoxidation of ethylbenzene with O2 in the absence of organic solvents than the latter. In addition, theprepared Mn-containing silylated MgAl LDH catalyst was highly stable and reusable.

Detection and Quantification of Fusarium oxysporum f. sp. niveum Race 1 in Plants and Soil by Real-time PCR

Xin Zhong,Yang Yang,Jing Zhao,Binbin Gong,Jingrui Li,Xiaolei Wu,Hongbo Gao,Guiyun Lü 한국식물병리학회 2022 Plant Pathology Journal Vol.38 No.3

Fusarium wilt caused by Fusarium oxysporum f. sp. niveum (Fon) is the most serious soil-borne disease in the world and has become the main limiting factor of watermelon production. Reliable and quick detection and quantification of Fon are essential in the early stages of infection for control of watermelon Fusarium wilt. Traditional detection and identification tests are laborious and cannot efficiently quantify Fon isolates. In this work, a real-time polymerase chain reaction (PCR) assay has been described to accurately identify and quantify Fon in watermelon plants and soil. The FONRT-18 specific primer set which was designed based on identified specific sequence amplified a specific 172 bp band from Fon and no amplification from the other formae speciales of Fusarium oxysporum tested. The detection limits with primers were 1.26 pg/μl genomic DNA of Fon, 0.2 pg/ng total plant DNA in inoculated plant, and 50 conidia/g soil. The PCR assay could also evaluate the relationships between the disease index and Fon DNA quantity in watermelon plants and soil. The assay was further used to estimate the Fon content in soil after disinfection with CaCN2. The real-time PCR method is rapid, accurate and reliable for monitoring and quantification analysis of Fon in watermelon plants and soil. It can be applied to the study of disease diagnosis, plantpathogen interactions, and effective management.

Identification of reference genes for normalization of gene expression in Liposcelis entomophila (Psocoptera: Liposcelididae)

Miao Shiyuan,Yang Binbin,Wang Suisui,Wang Zhengyan,Lu Yujie 한국응용곤충학회 2021 Journal of Asia-Pacific Entomology Vol.24 No.4

Liposcelis entomophila is a nuisance pest that seriously threatens the safety of stored grains owing in part of pesticide resistance. To facilitate better control of L. entomophila, future studies need to focus on gene function characterization. This requires the identification of suitable reference genes (RGs) for reverse-transcription quantitative PCR (RT-qPCR), which is crucial for the normalization of target gene expression. Here, we evalu ated the expression stability of 12 candidate RGs in L. entomophila across six experimental conditions (devel opmental stage, population, body part, phosphine fumigation, hypoxia induction, and temperature treatment). Under developmental conditions, ACTB, HSP70, and RPL23 were the most stable RGs. Among the different populations and body parts, RPL23, EF1a, and ACTB were the most stable RGs. Comparison of gene expression among adults under different environmental conditions revealed that at least seven RGs were fit for normalizing gene expression data. Among them, RPL23, EF1a, and ACTB showed the best fit as RGs in RT-qPCR analysis. After validation, our results demonstrated that EF1a and ACTB, as well as their combination, were the ideal RGs for L. entomophila across various experimental conditions. This study provides a comprehensive RG selection sug gestion for gene expression studies of L. entomophila and will facilitate future functional genomic research on the development and tolerance of environmental factors in psocids.