Investigation on Large Power AC Drive System

Chengsheng Wang,Chongjian Li,Li Li,Chunyi Zhu,Zhiming Lan 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5

The performance of the large power AC drive system for rolling mills should meet the need of production technology and adapt to the requirement of the electric network. In the paper, the cycloconverter system is introduced. With the development of large power electronics, application of the large power converter using the self-controllable devices such as IGCT becomes the trend. The three-level AC-DC-AC converter system with IGCTs whose rated power is 16MVA has been developed and put into use. And it is estimated that the AC-DC-AC converter system will be used in the drive for rolling mills in the near future.

The Development of IGCT-based Large Capacity Three-Level Dual-PWM Converter

Lan Zhiming,Li Chongjian,Li Yaohua,Zhu Chunyi,Wang Chengsheng 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5

In media and high voltage large capacity converter systems the Integrated Gate Commutated Thyristor (IGCT) take the place of Gate Turn Off Thyristor (GTO) duo to its outstanding performance. And IGCT-based large capacity three-level converters are widely used in industrial motor-driving field. In this paper the development of a set of IGCT-based large capacity three-level dual-PWM converter is introduced. The converter includes PWM rectifier, DC capacitors, PWM inverter. The topology of the converter is given. The close-loop control strategy and SVPWM algorithm of PWM rectifier is presented in this paper. The control strategy and algorithm of the PWM inverter is also presented. The experiments were performed and the results show that the converter reaches the design requirement and has excellent performance.

Connectivity map identifies luteolin as a treatment option of ischemic stroke by inhibiting MMP9 and activation of the PI3K/ Akt signaling pathway

Shijian Luo,Huiqing Li,Zhihuai Mo,Junjie Lei,Lingjuan Zhu,Yanxia Huang,Ruying Fu,Chunyi Li,Yihuan Huang,Kejia Liu,Wenli Chen,Lei Zhang 생화학분자생물학회 2019 Experimental and molecular medicine Vol.51 No.-

This study aimed to explore potential new drugs in the treatment of ischemic stroke by Connectivity Map (CMap) and to determine the role of luteolin on ischemic stroke according to its effects on matrix metalloproteinase-9 (MMP9) and PI3K/Akt signaling pathway. Based on published gene expression data, differentially expressed genes were obtained by microarray analysis. Potential compounds for ischemic stroke therapy were obtained by CMap analysis. Cytoscape and gene set enrichment analysis (GSEA) were used to discover signaling pathways connected to ischemic stroke. Cell apoptosis and viability were, respectively, evaluated by flow cytometry and an MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5- diphenyl-2-H-tetrazolium bromide) assay. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analysis were used to test the expression of MMP9 and the PI3K/Akt signaling pathway-related proteins in human brain microvascular endothelial cells (HBMECs) and tissues. Additionally, the infarct volume after middle cerebral artery occlusion (MCAO) was determined by a TTC (2,3,5-triphenyltetrazolium chloride) assay. The microarray and CMap analyses identified luteolin as a promising compound for future therapies for ischemic stroke. Cytoscape and GSEA showed that the PI3K/Akt signaling pathway was crucial in ischemic stroke. Cell experiments revealed that luteolin enhanced cell viability and downregulated apoptosis via inhibiting MMP9 and activating the PI3K/Akt signaling pathway. Experiments performed in vivo also demonstrated that luteolin reduced the infarct volume. These results suggest that luteolin has potential in the treatment of ischemic stroke through inhibiting MMP9 and activating PI3K/ Akt signaling pathway.

Production and immunogenicity of chimeric virus-like particles containing the spike glycoprotein of infectious bronchitis virus

Lishan Lv,Xiaoming Li,Genmei Liu,Ran Li,Qiliang Liu,Huifang Shen,Wei Wang,Chunyi Xue,Yongchang Cao 대한수의학회 2014 JOURNAL OF VETERINARY SCIENCE Vol.15 No.2

Infectious bronchitis virus (IBV) poses a severe threat to thepoultry industry and causes heavy economic losses worldwide. Vaccination is the most effective method of preventing infectionand controlling the spread of IBV, but currently availableinactivated and attenuated virus vaccines have somedisadvantages. We developed a chimeric virus-like particle(VLP)-based candidate vaccine for IBV protection. The chimericVLP was composed of matrix 1 protein from avian influenzaH5N1 virus and a fusion protein neuraminidase (NA)/spike 1 (S1)that was generated by fusing IBV S1 protein to the cytoplasmicand transmembrane domains of NA protein of avian influenzaH5N1 virus. The chimeric VLPs elicited significantly higherS1-specific antibody responses in intramuscularly immunizedmice and chickens than inactivated IBV viruses. Furthermore,the chimeric VLPs induced significantly higher neutralizationantibody levels than inactivated H120 virus in SPF chickens. Finally, the chimeric VLPs induced significantly higher IL-4production in mice. These results demonstrate that chimericVLPs have the potential for use in vaccines against IBV infection.

Efficient production of propylene and gasoline from methanol in multi-regime riser

Xiaojing Meng,Huiwen Huang,Qiang Zhang,Chunyi Li,Qiukai Cui 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.4

High gas-solid contact efficiency and low solid back-mixing are necessary to both promote methanol conversion and inhibit side reactions. Thus, a novel multi-regime reactor with dense-phase reaction section and dilutephase conveying region was designed. The reactor promoted stable reaction activity during a 300 h pilot-scale evaluation with high yields of propylene and gasoline. A process for maximum propylene and gasoline production from methanol (PGFM) characterized by moderate operating severity, application of ZSM-11 catalyst and novel reactor, and stratified reprocessing or etherification of light gasoline and C4 olefins was proposed. The PGFM process can be implemented in the existing FCC process and is considered to be more economic and flexible.

Dehydrogenation versus hydrogenolysis in the reaction of light alkanes over Ni-based catalysts

Guowei Wang,Shan Zhang,Xiaolin Zhu,Chunyi Li,Honghong Shan 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.86 No.-

Given the high cost of Pt-based catalysts and the environmental issue of CrOx-based catalysts indehydrogenation processes, Ni-based catalysts have been extensively explored as alternatives. In order totake the advantage of the high activation ability of Ni towards alkanes, herein, the reaction behaviors oflight alkanes, primarily dehydrogenation versus hydrogenolysis, over Ni-based catalysts have beenreviewed and probed. Ni-based catalysts exhibit an extremely high hydrogenolysis activity for lightalkanes. Different from the single hydrogenolysis reaction on the surface of Pt, multiple hydrogenolysis ofalkane molecules occurs over Ni sites. The successive α-scission of C C bond over Ni sites results in thegeneration of abundant methane and coke. To selectively activate C H bond of alkanes and prohibit C Cbond rupture, one feasible approach is to introduce effective barriers to destroy the aggregated Niensembles active for hydrogenolysis. The promoting mechanism of different barriers (S, P, Cu, Sn, etc.) hasbeen summarized and analyzed. The geometric effect of introduced barriers facilitates the dispersion ofNi particles, and electronic effect reduces the desorption energy of olefins and avoids undesiredsecondary reactions. Among all these catalysts, NiS and NiSn-based catalysts demonstrate the mostoutstanding dehydrogenation performance and show great potential for industrial applications.

Effect of acidic properties of hierarchical HZSM-5 on the product distribution in methanol conversion to gasoline

Huiwen Huang,Hui Zhu,Qiang Zhang,Chunyi Li 한국화학공학회 2019 Korean Journal of Chemical Engineering Vol.36 No.2

Hierarchical ZSM-5 zeolites with different SiO2/Al2O3 ratio but similar crystal size were directly synthesized by a single-template hydrothermal method, and the intrinsic effect of acidic properties on their catalytic performance in methanol to gasoline (MTG) reaction was comprehensively investigated. The physicochemical properties of HZSM-5 zeolites were characterized by XRD, N2 adsorption-desorption, SEM, NH3-TPD, FTIR, and TGA techniques. The results show good linear correlations between the yields of gasoline components and the relative content of Brønsted acid sites, and the hierarchical HZSM-5 zeolite with SiO2/Al2O3 molar ratio of 200 was firstly found to exhibit high reactivity, excellent product distribution and superior stability in MTG reaction, which can be attributed to its appropriate acid distribution with moderate Brønsted acid sites and proper B/L ratio, predominantly promoting gasoline range hydrocarbons production and inhibiting side reactions.

Conversion of methanol into light olefins over ZSM-11 catalyst in a circulating fluidized-bed unit

Xiaojing Meng,Huiwen Huang,Qiang Zhang,Minxiu Zhang,Chunyi Li,Qiukai Cui 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.3

Methanol conversion and the reaction pathway were investigated in a pilot-scale circulating fluidized-bed (CFB) unit over hierarchical ZSM-11 catalyst. Experimental results indicated that ZSM-11 catalyst was highly resistant to external coke due to the formation of mesopores. Elevated temperatures favored the production of propylene and butylene and decreased the yield of ethylene. Additionally, no direct relations were shown between the formation of ethylene and other products under different pressures, suggesting that ethylene was a primary product produced at the initial of the reaction. Methylation-cracking and oligomerization were verified as the main reaction pathway for the formation of C3 + alkenes., Methylation and oligomerization of olefins were dominated under high methanol partial pressure and consequently responsible for the production of higher olefins, while the b-scission of C7 = for propene and butylene, and C8 = for butylene were enhanced at low methanol partial pressure.

Molecular evidence for adaptive evolution of olfactory-related genes in cervids

Hengxing Ba,Tao Qin,Zexi Cai,Wenyuan Liu,Chunyi Li 한국유전학회 2020 Genes & Genomics Vol.42 No.4

Background Cervids have evolved very successful means for survival and thriving to adapt to various climates and environments. One of these successful means might be the effective and efficient way of communication. To support this notion, cervids are well equipped with a variety of skin glands that distribute in different body regions. However, studies relevant to adaptive evolution in cervids, particularly on olfactory reception at the molecular level, have thus far not been reported. Objective To provide valuable insights into molecular evidence for the adaptive evolution of olfactory-related gene in cervids. Methods Based on recently sequenced genomes of cervids and closely-related-species, we performed comparative genomic analysis at genome level using bioinformatics tools. Results Tree topology strongly supported that Bovidae was the sister group of Moschidae and both formed a branch that was then clustered with Cervidae. Expansion of heavy chain genes of the dynein family and 51 rapidly evolving genes could be associated with adaptation of cilia that serve as sensory organelles and act as cellular antennae. Based on the branchsite model test along the deer branch spanning 7–21 mammalian species, 14 deer olfactory receptor genes were found to be undergoing positive selection pressure and 89 positive selection sites (probability > 60%) had amino acid substitutions unique to deer. Conclusion This study, for the first time, provides significant molecular evidence for adaption of olfactory-related genes of cervids according to their olfactory behavior.

Effects of chromium picolinate on fat deposition, activity and genetic expression of lipid metabolism-related enzymes in 21 day old Ross broilers

Chen, Guangxin,Gao, Zhenhua,Chu, Wenhui,Cao, Zan,Li, Chunyi,Zhao, Haiping Asian Australasian Association of Animal Productio 2018 Animal Bioscience Vol.31 No.4

Objective: This experiment was conducted to investigate the effects of chromium picolinate (CrP) on fat deposition, genetic expression and enzymatic activity of lipid metabolism-related enzymes. Methods: Two hundred forty one-day-old Ross broilers were randomly divided into 5 groups with 4 replicates per group and 12 Ross broiler chicks per replicate. The normal control group was fed a basal diet, and the other groups fed the same basal diet supplemented with 0.1, 0.2, 0.4, and 0.8 mg/kg CrP respectively. The experiment lasted for 21 days. Results: Added CrP in the basal diet decreased the abdominal fat, had no effects on subcutaneous fat thickness and inter-muscular fat width; 0.2 mg/kg CrP significantly decreased the fatty acid synthase (FAS) enzymatic (p<0.05); acetyl-CoA carboxylase (ACC) enzymatic activity decreased in all CrP groups (p<0.05); hormone-sensitive lipase (HSL) enzymatic activity also decreased, but the change was not significant (p>0.05); 0.4 mg/kg CrP group significantly decreased the lipoprotein lipase (LPL) enzymatic activity. FAS mRNA expression increased in all experimental groups, and the LPL mRNA expression significantly increased in all experimental groups (p<0.05), but not 0.2 mg/kg CrP group. Conclusion: The results indicated that adding CrP in basal diet decreased the abdominal fat percentage, had no effects on subcutaneous fat thickness and inter-muscular fat width, decreased the enzymatic activity of FAS, ACC, LPL and HSL and increased the genetic expression levels of FAS and LPL.