Experimental Study on Thermal Catalytic Degradation of SF6 Waste Gas by Metal Phosphate

Zhang Xiaoxing,Li Xiaohan,Wang Yi,Meng Fei,Zou Yi,Tian Shuangshuang,Cui Zhaolun 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.2

In recent years, SF6 has been widely used in the electrical industry. The amount of SF6 waste gas produced by the corresponding gas insulated equipment is increasing year by year. However, SF6 has high global warming potential and long atmospheric life. Proper treatment of SF6 waste gas is particularly important for environmental protection. Thermal degradation can effectively eliminate the greenhouse effect caused by direct emission of SF6. In this paper, AlPO4, Zr3(PO4)4 and CePO4 were used as catalysts to degrade SF6/air mixture gas (The concentration of SF6 is 15%) at 800 °C. The concentration of SF6 gas was detected by gas chromatography (GC), and the gas decomposition products of SF6 were detected by gas chromatography mass spectrometry (GCMS) and fourier transform infrared spectroscopy (FTIR). The surface morphology and composition of the catalyst were analyzed by scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). The results show that the three kinds of metal phosphates can promote the decomposition of SF6 gas, among which CePO4 had the best catalytic degradation effect, and the degradation rate of SF6 reached 84.7% in 12 h. The main products of SF6 gas thermal catalytic degradation include SF4, S2F10, SO2F2, SOF2, SiF4 and SO2 gas, etc. SEM scanning image shows that there were some objects adsorbed on the surface of CePO4 catalyst after the experiment. XPS spectra showed that Si and F elements were added to the catalyst. According to the binding energy, SiF4 was adsorbed on the catalyst. After the experiment, CeF3 was produced by CePO4 catalyst. Different catalysts have their own selectivity to the decomposition products of SF6, which is convenient for the treatment of products, and it is of great significance to eliminate the greenhouse effect caused by the waste gas of SF6.

Rh-doped carbon nanotubes as a superior media for the adsorption of O2 and O3 molecules: a density functional theory study

Hao Cui,Xiaoxing Zhang,Qiang Yao,Yulong Miao,Ju Tang 한국탄소학회 2018 Carbon Letters Vol.28 No.-

Transition-metal-embedded carbon nanotubes (CNTs) have been accepted as a novel type of sensing material due to the combined advantage of the transition metal, which possesses good catalytic behavior for gas interaction, and CNTs, with large effective surface areas that present good adsorption ability towards gas molecules. In this work, we simulate the adsorption of O2 and O3 onto Rh-doped CNT in an effort to understand the adsorbing behavior of such a surface. Results indicate that the proposed material presents good adsorbing ability and capacities for these two gases, especially O3 molecules, as a result of the relatively large conductivity changes. The frontier molecular orbital theory reveals that the conductivity of Rh-CNT would undergo a decrease after the adsorption of two such oxidizing gases due to the lower electron activity and density of this media. Our calculations are meaningful as they can supply experimentalists with potential sensing material prospects with which to exploit chemical sensors.

Geometric structure and electronic behavior of Rh decorating effect on zigzag CNTs (n=7-12): A DFT study

Hao Cui,Xiaoxing Zhang,Yongjian Zhou,Jun Zhang 한국탄소학회 2018 Carbon Letters Vol.26 No.-

Comprehensive calculations of the Rh decoration effect on zigzag CNTs with n ranging from 7 to 12 were conducted in this work to understand the effect of Rh doping on geometric structures and electronic behaviors upon metallic and semiconducting CNTs. The obtained results indicated that Rh dopant not only contributes to the deformation of C-C bonds on the sidewall of CNTs, but also transforms the electron distribution of related complexes, thereby leading to a remarkable increase of the conductivity of pure CNTs given the emerged novel state within the energy gap for metallic CNTs and the narrowed energy gap for semiconducting CNTs. Our calculations will be meaningful for exploiting novel CNT-based materials with better sensitivity to electrons and higher electrical conductivity compared with pure CNTs.

Theoretical study on electrical behavior of carbon chain inserted single-walled carbon nanotubes compared with Pt doped one

Hao Cui,Xiaoxing Zhang,Hanyan Xiao,Ju Tang 한국탄소학회 2018 Carbon Letters Vol.25 No.-

Carbon chain inserted carbon nanotubes (CNTs) have been experimentally proven having undergone pronounced property change in terms of electrical conductivity compared with pure CNTs. This paper simulates the geometry of carbon chain inserted CNTs and analyzes the mechanism for conductivity change after insertion of carbon chain. The geometric simulation of Pt doped CNT was also implemented for comparison with the inserted one. The results indicate that both modification by Pt atom on the surface of CNT and addition of carbon chain in the channel of the tube are effective methods for transforming the electrical properties of the CNT, leading to the redistribution of electron and thereby causing the conductivity change in obtained configurations. All the calculations were obtained based on density functional theory method.

Genome-wide identification and expression analysis of the BTB domain-containing protein gene family in tomato

Jinhua Li,Xiaoxing Su,Yinlei Wang,Wei Yang,Yu Pan,Chenggang Su,Xingguo Zhang 한국유전학회 2018 Genes & Genomics Vol.40 No.1

BTB (broad-complex, tramtrack, and bric-abrac) family proteins are characterized by the presence of a protein–protein interaction BTB domain. BTB proteins have diverse functions, including transcriptional regulation, protein degradation, chromatin remodeling, and cytoskeletal regulation. However, little is known about this gene family in tomato (Solanum lycopersicum), the most important model plant for crop species. In this study, 38 BTB genes were identified based on tomato whole-genome sequence. Phylogenetic analysis of BTB proteins in tomato revealed that SlBTB proteins could be divided into at least 4 subfamilies. The SlBTB proteins contains 1–3 BTB domains, and several other types of functional domains, including KCTD (Potassium channel tetramerization domain-containing), the MATH (meprin and TRAF homology), ANK (Ankyrin repeats), NPR1 (nonexpressor of pathogenesis-related proteins1), NPH3 (Nonphototropic Hypocotyl 3), TAZ zinc finger, C-terminal Kelch, Skp1 and Arm (Armadillo/betacatenin- like repeat) domains are also found in some tomato BTB proteins. Moreover, their expression patterns in tissues/ stages, in response to different abiotic stress treatments and hormones were also investigated. This study provides the first comprehensive analysis of BTB gene family in the tomato genome. The data will undoubtedly be useful for better understanding the potential functions of BTB genes, and their possible roles in mediating hormone cross-talk and abiotic stress in tomato as well as in some other relative species.

SF6 abatement in a packed bed plasma reactor: Role of zirconia size and optimization using RSM

Yuan Tian,Xiaoxing Zhang,Yufei Wang,Zhaolun Cui,Ju Tang 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.94 No.-

This work describes plasma destruction of SF6 in a zirconia (ZrO2) packed bed plasma reactor (PBR). Electric signals, equivalent parameters, emission spectra and degradation results have been utilized toevaluate the influence of ZrO2 size on PBR discharge characteristics and SF6 degradation. The resultspresent that the size of ZrO2 has a significant impact on PBR discharge characteristics due to its influenceon physical parameters. Moreover, bigger ZrO2 beads packing shows a better performance in SF6degradation because of longer gas residence time. In addition, the key operating parameters includingflowrate, SF6 concentration, oxygen concentration, and water vapor concentration were optimized byresponse surface methodology (RSM) with Box-Behnken design (BBD). The proposed optimization modelshows satisfactory correlation between the predicted and actual results. For energy yield (EY), the mutualeffect offlowrate, SF6 concentration and water vapor concentration was significant. For SO2F2 selectivity,the mutual effect of SF6 concentration and water vapor concentration was significant. The optimum SF6abatement was predicted from RSM as 14.64 g/kWh and 14.42% for EY and SO2F2 selectivity atflowrate of200 mL/min, SF6 concentration of 3%, oxygen concentration of 0.83% and water vapor concentration of1.89%.

Antioxidant and Anti-inflammatory Properties of Chinese Ilicifolius Vegetable (Acanthopanax trifoliatus (L) Merr) and Its Reference Compounds

Huaqian Wang,Dongli Li,Zhi-Yun Du,Mou-Tuan Huang,Xiaoxing Cui,Yujing Lu,Chenyue Li,Swee Lian Woo,Allan H Conney,Xi Zheng,Kun Zhang 한국식품과학회 2015 Food Science and Biotechnology Vol.24 No.3

Stems and leaves of Acanthopanax trifoliatus (L) Merr (AT) are commonly used as an edible vegetable in China. The scientific basis of antioxidant and antiinflammatory activities of AT was investigated. The polyphenol contents and free radical scavenging activities of AT ethanol extracts (EAT) were determined. Chlorogenic acid, isochlorogenic acid A, isochlorogenic acid C, and rutin were identified as major components in EAT. LPS-induced NO production in RAW264.7 cells was decreased significantly (p<0.05) after EAT treatment, compared with controls. In vivo studies indicated that EAT had more activity than chlorogenic acid per mg of dry weight for inhibition of TPA-induced ear edema. TPA-induced increases in cytokine production (TNF-α, IL-6, MMP-9, and TIMP-1) were significantly (p<0.05) reduced by EAT treatment, compared with controls. EAT exerts anti-inflammatory activities probably due, at least in part, to chlorogenic acid.

Application of SA-SVM Incremental Algorithm in GIS PD Pattern Recognition

Ju Tang,Ran Zhuo,DiBo Wang,JianRong Wu,XiaoXing Zhang 대한전기학회 2016 Journal of Electrical Engineering & Technology Vol.11 No.1

With changes in insulated defects, the environment, and so on, new partial discharge (PD) data are highly different from the original samples. It leads to a decrease in on-line recognition rate. The UHF signal and pulse current signal of four kinds of typical artificial defect models in gas insulated switchgear (GIS) are obtained simultaneously by experiment. The relationship map of ultrahigh frequency (UHF) cumulative energy and its corresponding apparent discharge of four kinds of typical artificial defect models are plotted. UHF cumulative energy and its corresponding apparent discharge are used as inputs. The support vector machine (SVM) incremental method is constructed. Examples show that the PD SVM incremental method based on simulated annealing (SA) effectively speeds up the data update rate and improves the adaptability of the classifier compared with the original method, in that the total sample is constituted by the old and new data. The PD SVM incremental method is a better pattern recognition technology for PD on-line monitoring.

Application of SA-SVM Incremental Algorithm in GIS PD Pattern Recognition

Tang, Ju,Zhuo, Ran,Wang, DiBo,Wu, JianRong,Zhang, XiaoXing The Korean Institute of Electrical Engineers 2016 Journal of Electrical Engineering & Technology Vol.11 No.1

With changes in insulated defects, the environment, and so on, new partial discharge (PD) data are highly different from the original samples. It leads to a decrease in on-line recognition rate. The UHF signal and pulse current signal of four kinds of typical artificial defect models in gas insulated switchgear (GIS) are obtained simultaneously by experiment. The relationship map of ultra-high frequency (UHF) cumulative energy and its corresponding apparent discharge of four kinds of typical artificial defect models are plotted. UHF cumulative energy and its corresponding apparent discharge are used as inputs. The support vector machine (SVM) incremental method is constructed. Examples show that the PD SVM incremental method based on simulated annealing (SA) effectively speeds up the data update rate and improves the adaptability of the classifier compared with the original method, in that the total sample is constituted by the old and new data. The PD SVM incremental method is a better pattern recognition technology for PD on-line monitoring.