Multielectrochromic Copolymers Based on Thiophene Derivatives: Tunable Optoelectronic Properties

Yafei Guo,Gaoyong Liang,Mengjie Dong,Meihui Wang,Xinmin Hao 한국섬유공학회 2022 Fibers and polymers Vol.23 No.9

In this study, a series of copolymers based on 3-methoxythiophene(MOT) and 3,4-ethylenedioxythiophene(EDOT) have been prepared by electrochemical method in boron trifluoride diethyl etherate (BFEE). The copolymers arecharacterized by FTIR, XPS, SEM and cyclic voltammograms. The MOT/EDOT ratio in the polymer chain decreases withthe decreasing MOT/EDOT feed ratio, and low polymerization potential incorporates more EDOT units into the polymerchain. The electrochromic properties of the copolymers can be greatly tuned by the applied MOT/EDOT feed ratio. Absorption peak of the neutral copolymer presents red-shift with increasing feed ratio, and each copolymer has multicolorelectrochromism. In addition, the copolymers present fast-switching response, reasonable coloration efficiency and goodstability. All these indicate that the copolymers based on facile, commercial MOT and EDOT are promising candidates forelectrochromic applications.

Effects of dietary poly-β-hydroxybutyrate (PHB) on microbiota composition and the mTOR signaling pathway in the intestines of Litopenaeus vannamei

Yafei Duan,Yue Zhang,Hongbiao Dong,Yun Wang,Jiasong Zhang 한국미생물학회 2017 The journal of microbiology Vol.55 No.12

Poly-β-hydroxybutyrate (PHB) is a natural polymer of the short chain fatty acid β-hydroxybutyrate, which acts as a microbial control agent. The mammalian target of the rapamycin (mTOR) signaling pathway plays a crucial role in intestine inflammation and epithelial morphogenesis. In this study, we examined the composition of intestine microbiota, and mTOR signaling-related gene expression in Pacific white shrimp Litopenaeus vannamei fed diets containing different levels of PHB: 0% (Control), 1% (PHB1), 3% (PHB3), and 5% (PHB5) (w/w) for 35 days. High-throughput sequencing analysis revealed that dietary PHB altered the composition and diversity of intestine microbiota, and that the microbiota diversity decreased with the increasing doses of PHB. Specifically, dietary PHB increased the relative abundance of Proteobacteria and Tenericutes in the PHB1 and PHB5 groups, respectively, and increased that of Gammaproteobacteria in the three PHB groups. Alternatively, PHB decreased Alphaproteobacteria in the PHB3 and PHB5 groups. At the genus level, dietary PHB increased the abundance of beneficial bacteria, such as Bacillus, Lactobacillus, Lactococcus, Clostridium, and Bdellovibrio. The relative mRNA expression levels of the mTOR signaling-related genes TOR, 4E-BP, eIF4E1α, and eIF4E2 all increased in the three PHB treatment groups. These results revealed that dietary PHB supplementation had a beneficial effect on intestine health of L. vannamei by modulating the composition of intestine microbiota and activating mTOR signaling.

Wireless Power Transfer for Electric Vehicles Charging Based on Hybrid Topology Switching With a Single Inverter

Yafei Chen,Hailong Zhang,Dong-Hee Kim,Sung-Jun Park,Seong-Mi Park 한국산업융합학회 2020 한국산업융합학회 논문집 Vol.23 No.2

In wireless power transfer (WPT) system, the conventional compensation topologies only can provide a constant current (CC) or constant voltage (CV) output under their resonant conditions. It is difficult to meet the CC and CV hybrid charging requirements without any other schemes. In this study, a switching hybrid topology (SHT) is proposed for CC and CV electric vehicle (EV) battery charging. By utilizing an additional capacitor and two AC switches (ACSs), a double-side LCC (DS-LCC) and an inductor and double capacitors-series (LCC-S) topologies are combined. According to the specified CC and CV charging profile, the CC and CV charging modes can be flexibly converted by the two additional ACSs. In addition, zero phase angle (ZPA) also can be achieved in both charging modes. In this method, because the operating frequency is fixed, without using PWM control, and only a small number of devices are added, it has the benefits of low-cost, easy-controllability and high efficiency. A 3.3-kW experimental prototype is configured to verify the proposed switching hybrid charger. The maximum DC efficiencies (at 3.3-kW) of the proposed SHT is 92.58%.

Macroscopic Zn-doped a-Fe2O3/graphene aerogel mediated persulfate activation for heterogeneous catalytic degradation of sulfamonomethoxine wastewater

Shuying Dong,Xuanxuan Yan,Wenli Li,Yafei Liu,Xiaoxu Han,Xiaodan Liu,Jinglan Feng,Chongfei Yu,Chunyan Zhang,Jianhui Sun 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.108 No.-

In order to obtain a robust, durable and efficient heterogeneous catalyst, macroscopic monolithic Zndopeda-Fe2O3/graphene aerogel (GA) hybrid architecture with integrated morphology and hierarchicallyporous structure were controllably synthesized via a facile in-situ hydrothermal method and then used aspersulfate (PS) activator for sulfamonomethoxine (SMM) wastewater purification. Several key reactionparameters including the initial SMM concentration, reaction temperature, coexisting inorganic anionsand SMM in real natural water samples had different influence on the SMM removal efficiency. The catalyticefficiency of Zn-doped a-Fe2O3/GA with the molar ratio of Fe/Zn = 2:1.5 was about 66%, 62%, 66%and 11%33% higher than that of GA, a-Fe2O3/GA, Zn/GA and other Fe/Zn molar ratio. The improvedactivity of Fe/Zn = 2:1.5 benefits from the synergistic effects of the sp2 hybridized carbon and porousframework, as well as the surface oxygenic functional groups, which accelerate the pollutant/oxidant dispersionand electron transfer. Electron paramagnetic resonance results indicate that OH, 1O2 and SO4radicals account for the catalytic degradation of SMM and the activation of PS in present system is differentfrom conventional homogeneous systems, and speculate mechanism was proposed based on theobtained data.

Wireless Power Transfer for Electric Vehicles Charging Based on Hybrid Topology Switching With a Single Inverter

Chen, Yafei,Zhang, Hailong,Kim, Dong-Hee,Park, Sung-Jun,Park, Seong-Mi The Korean Society of Industry Convergence 2020 한국산업융합학회 논문집 Vol.23 No.2

In wireless power transfer (WPT) system, the conventional compensation topologies only can provide a constant current (CC) or constant voltage (CV) output under their resonant conditions. It is difficult to meet the CC and CV hybrid charging requirements without any other schemes. In this study, a switching hybrid topology (SHT) is proposed for CC and CV electric vehicle (EV) battery charging. By utilizing an additional capacitor and two AC switches (ACSs), a double-side LCC (DS-LCC) and an inductor and double capacitors-series (LCC-S) topologies are combined. According to the specified CC and CV charging profile, the CC and CV charging modes can be flexibly converted by the two additional ACSs. In addition, zero phase angle (ZPA) also can be achieved in both charging modes. In this method, because the operating frequency is fixed, without using PWM control, and only a small number of devices are added, it has the benefits of low-cost, easy-controllability and high efficiency. A 3.3-kW experimental prototype is configured to verify the proposed switching hybrid charger. The maximum DC efficiencies (at 3.3-kW) of the proposed SHT is 92.58%.

Bidirectional DC-DC Converter Based on Quasi-Sepic for Battery Charging System

Hailong Zhang,Yafei Chen,Dong-Hee Kim,Sung-Jun Park,Seong-Mi Park 한국산업융합학회 2020 한국산업융합학회 논문집 Vol.23 No.2

In order to satisfy the voltage levels of the low voltage battery side and high voltage DC bus, a high voltage gain with bidirectional operation is required. In this system, the cost effectiveness of the design is a critical factor; therefore, the system should be designed using a small number of components. This paper propose a novel bidirectional converter composed with a quasi-sepic and switched-indictor network. The proposed converter consists a small number of components with a high voltage gain ratio. Detailed analysis are made with respect to the operating mode, number of components, voltage and current ripple and efficiency. To verify performance of the proposed converter, simulation was performed is this paper. The simulation results are shown to verify the feasibility and performance of the proposed bidirectional converter.

Transformerless Bidirectional DC-DC Converter for Battery Storage System with High Voltage Gain

Hailong Zhang,Yafei Chen,Chang-Su Shin,Sung-Jun Park,Dong-Hee Kim 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

Bidirectional DC-DC converters with wide voltage conversion ratio are essential in energy storage systems. In these systems (ESS), cost effective design is important factor, therefore, it needs to be designed with small numbers of component. This paper proposes a family of high voltage gain bidirectional converter based on the integration of Boost converter with Ćuk, SEPIC, BUCK-BOOST converters respectively. Detail comparisons are progressed in terms of operating mode, numbers of component, and efficiency. The experiment results are carried to verify the proposed converter family. The results show that converter I present the highest efficiency in boost mode (92%) and in buck mode (92.2%).

Requirement of the isocitrate lyase gene ICL1 for VPS41-mediated starvation response in Cryptococcus neoformans

Zhe Xu,Yafei Zhi,Jianzhang Dong,Benfeng Lin,Di Ye,Xiaoguang Liu 한국미생물학회 2016 The journal of microbiology Vol.54 No.7

Cryptococcus neoformans is a major cause of fungal meningitis in individuals with impaired immunity. Our previous studies have shown that the VPS41 gene plays a critical role in the survival of Cryptococcus neoformans under nitrogen starvation; however, the molecular mechanisms underlying VPS41-mediated starvation response remain to be elucidated. In the present study, we show that, under nitrogen starvation, VPS41 strongly enhanced ICL1 expression in C. neoformans and that overexpression of ICL1 in the vps41 mutant dramatically suppressed its defects in starvation response due to the loss of VPS41 function. Moreover, targeted deletion of ICL1 resulted in a dramatic decline in viability of C. neoformans cells under nitrogen deprivation. Taken together, our data suggest a model in which VPS41 up-regulates ICL1 expression, directly or indirectly, to promote survival of C. neoformans under nitrogen starvation.

White-Matter Hyperintensities and Lacunar Infarcts Are Associated with an Increased Risk of Alzheimer’s Disease in the Elderly in China

Shuai Ye,Shuyang Dong,Jun Tan,Le Chen,Hai Yang,Yang Chen,Zeyan Peng,Yingchao Huo,Juan Liu,Mingshan Tang,Yafei Li,Huadong Zhou,Yong Tao 대한신경과학회 2019 Journal of Clinical Neurology Vol.15 No.1

Background and Purpose This study investigated the contribution of white-matter hyperintensities (WMH) and lacunar infarcts (LI) to the risk of Alzheimer’s disease (AD) in an elderly cohort in China. Methods Older adults who were initially cognitively normal were examined with MRI at baseline, and followed for 5 years. WMH were classified as mild, moderate, or severe, and LI were classified into a few LI (1 to 3) or many LI (≥4). Cognitive function was assessed using the Mini Mental State Examination and the Activities of Daily Living scale. Results Among the 2,626 subjects, 357 developed AD by the end of the 5-year follow-up period. After adjusting for age and other potential confounders, having only WMH, having only LI, and having both WMH and LI were associated with an increased risk of developing AD compared with having neither WMH nor LI. Moderate and severe WMH were associated with an increased risk of developing AD compared with no WMH. Furthermore, patients with many LI had an increased risk of developing AD compared with no LI. Conclusions Having moderate or severe WMH and many LI were associated with an increased risk of developing AD, with this being particularly striking when both WMH and LI were present.

Bidirectional DC-DC Converter Based on Quasi-Sepic for Battery Charging System

Zhang, Hailong,Chen, Yafei,Kim, Dong-Hee,Park, Sung-Jun,Park, Seong-Mi The Korean Society of Industry Convergence 2020 한국산업융합학회 논문집 Vol.23 No.2

In order to satisfy the voltage levels of the low voltage battery side and high voltage DC bus, a high voltage gain with bidirectional operation is required. In this system, the cost effectiveness of the design is a critical factor; therefore, the system should be designed using a small number of components. This paper propose a novel bidirectional converter composed with a quasi-sepic and switched-indictor network. The proposed converter consists a small number of components with a high voltage gain ratio. Detailed analysis are made with respect to the operating mode, number of components, voltage and current ripple and efficiency. To verify performance of the proposed converter, simulation was performed is this paper. The simulation results are shown to verify the feasibility and performance of the proposed bidirectional converter.