Catalytic Combustion of Propionaldehyde over Alumina-Supported Manganese Oxides

Yi Liu,Zhong-Kun Ma,Seong-Gyu Seo 한국냄새환경학회 2011 실내환경 및 냄새 학회지 Vol.10 No.1

In this study, the catalytic combustion of propionaldehyde, which is an Offensive Odorant Substance assigned by the Korean Ministry of Environment (KMOE), over alumina-supported manganese oxide (Mn/Al2 O3) catalysts was investigated. The combustion reaction was carried out in a fixed-bed reactor at the temperature range of 200 ∼340 ℃. Mn/Al2O3 catalysts with Mn loadings ranging from 3.9 to 18.3 wt.% were prepared by impregnation method. The physicochemical characteristics of the catalysts were analyzed by X-Ray Diffraction (XRD), Scanning Electronic Microscopy (SEM) and Brunauer-Emmett-Teller (BET). The Mn crystalline phases of the Mn/Al2O3 catalysts were identified as α-Mn2O3 and β-MnO2. Mn oxides were covered on γ-Al2O3 supports with an average diameter of around 1 μm. With the increase of Mn loadings, the BET surface areas, pore volumes and average pore diameters of the Mn/Al2O3 catalysts decreased. The catalytic activities of Mn/Al2O3 catalysts increased as the Mn loading was increased from 3.9 wt.% to 18.3 wt.%. The catalyst with 18.3 wt.% Mn loading was able to achieve 100% propionaldehyde conversion at 260 ℃. For the same temperature, a lower Gas Hourly Space Velocity (GHSV) and a lower propionaldehyde concentration promote the complete combustion of propionaldehyde.

A Study on the Early Stage of Development of China Classic Dance Based on the Stylization and Technique of Traditional Chinese Opera

Yi Xun Zhong 대한무용학회 2009 대한무용학회논문집 Vol.58 No.-

Thrombin promotes epithelial ovarian cancer cell invasion by inducing epithelial-mesenchymal transition

Yi-Cun Zhong,Ting Zhang,Wen Di,Wei-Ping Li 대한부인종양학회 2013 Journal of Gynecologic Oncology Vol.24 No.3

Objective: Over-expression of thrombin in ovarian cancer cells is associated with poor prognosis. In this study, we investigated the role of thrombin in inducing epithelial-mesenchymal transition (EMT) in SKOV3 epithelial ovarian cancer cells. Methods: After thrombin treatment SKOV3 cells were subjected to western blots, reverse-transcription PCR, and enzyme-linked immunosorbent assay to quantify EMT-related proteins, mRNA expression of SMAD2, DKK1, and sFRP1, and the secretion of matrix metalloproteinases (MMPs) and cytokines. Meanwhile, invasion ability was evaluated using transwell assays. Results: The results indicated a dose- and time-dependent down-regulation of E-cadherin and upregulation of N-cadherin and vimentin in thrombin-treated SKOV3 cells, compared with the thrombin-free control group (p<0.05). There was a dose-and time-dependent increase in the levels of SMAD2 and DKK1 mRNAs and a decrease in the levels of sFRP1 mRNA in thrombin-treated SKOV3 cells compared to control cells (p<0.05). Thrombin-treated SKOV3 cells exhibited increased secretion of MMP-9, MMP-2, interleukin (IL)-8, and IL-6 and increased invasion compared to untreated cells (p<0.05). Thrombin altered the morphology of SKOV3 cells to a spindle-like phenotype. Addition of hirudin to thrombin-treated cells reversed the effects of thrombin. Conclusion: Thrombin induced EMT and promoted the invasion of SKOV3 cells, possibly via distinct signaling pathways. Hirudin inhibited the effects of thrombin, suggesting that anticoagulant therapy could be a novel therapeutic strategy for ovarian carcinoma.

No Blind Spot: Network Coverage Enhancement Through Joint Cooperation and Frequency Reuse

Yi Zhong,Pengcheng Qiao,Wenyi Zhang,Fu-chun Zheng 한국통신학회 2016 Journal of communications and networks Vol.18 No.5

Both coordinated multi-point transmission and frequencyreuse are effective approaches to mitigate inter-cell interferenceand improve network coverage. The motivation of thiswork is to explore the manner to effectively utilize the spectrum resourceby reasonably combining cooperation and frequency reuse. The Mat´ern cluster process, which is appropriate to model networkswith hot spots, is used to model the spatial distributionof base stations. Two cooperative mechanisms, coherent and noncoherentjoint transmission (JT), are analyzed and compared. Wealso evaluate the effect of multiple antennas and imperfect channelstate information. The simulation reveals that the proposed approachto combine cooperation and frequency reuse is effective toimprove the network coverage for users located at both the centerand the boundary of the cooperative region.

Continuous Sheet Metal Forming for Doubly Curved Surface Parts

Zhong-Yi Cai,Ying-Wu Lan,Ming-Zhe Li,Zhi-Qing Hu,Mi Wang 한국정밀공학회 2012 International Journal of Precision Engineering and Vol. No.

Continuous sheet metal forming (CSMF) is a novel technology for manufacturing doubly curved sheet metal parts. In this process,an upper flexible roll and two lower flexible rolls are employed as a forming tool, with the rotation of flexible rolls, the sheet metal is bent in the longitudinal and transverse directions simultaneously. In this study, the basic principle of CSMF system is introduced and the basic mathematical model to control the CSMF process is presented. Based on the analysis of the sheet metal deformation in longitudinal direction, the formulations to determine the finial curvature of the deformed sheet metal and to estimate the downward displacement of upper roll are obtained. Forming experiments for torus-shaped surface and saddle-shaped surface were carried out. The dimensional accuracy and smoothness of the CSMF parts were measured and analyzed. The experiment results confirm the validity of the presented mathematical models and shows that CSMF can be effectively used in forming of doubly curved surface parts.

Study on Aging Characteristics and Chemical Composition of Hydrogenated Transformer Oil

Yi-Hua Qian,Yi-Bin Huang,Qiang Fu,Zhen-Sheng Zhong 대한전기학회 2013 Journal of Electrical Engineering & Technology Vol.8 No.3

Under the condition of Baader aging, the chemical composition variation and the influence of transformer oil aging on electrical properties such as dielectric loss factor and physicchemical properties such as interfacial tension were studied in the aging precess. Moreover, the correlation between hydrogenated transformer oil electrical and physic-chemical properties and its chemical composition variation were also investigated. The results show that these parameters of physic-chemical and electrical properties of hydrogenated transformer oil relate to each other and have closed correlation with chemical composition.

A Comparative Study of the Effects of Different Decellularization Methods and Genipin-Cross-Linking on the Properties of Tracheal Matrices

Yi Zhong,Ai Jiang,Fei Sun,Yuanfan Xiao,Ying Gu,Lei Wu,Yujie Zhang,Hongcan Shi 한국조직공학과 재생의학회 2019 조직공학과 재생의학 Vol.16 No.1

BACKGROUND: Different decellularization methods can affect the integrity and the biomechanical and biocompatible properties of the tracheal matrix. Natural cross-linking with genipin can be applied to improve those properties. The goals of this study were to evaluate the effects of different decellularization methods on the properties of genipin-cross-linked decellularized tracheal matrices in rabbits. METHODS: The tracheas of New Zealand rabbits were decellularized by the Triton-X 100-processed method (TPM) and the detergent-enzymatic method (DEM) and were then cross-linked with genipin. Mechanical tests, haematoxylin–eosin staining, Masson trichrome staining, Safranin O staining, DAPI staining, scanning electronic microscopy (SEM), and biocompatibility tests were used to evaluate the treatment. The bioengineered trachea and control trachea were then implanted into allogeneic rabbits for 30 days. The structural and functional analyses were performed after transplantation. RESULTS: The biomechanical tests demonstrated that the biomechanical properties of the decellularized tracheas decreased and that genipin improved them (p\0.05). The histological staining results revealed that most of the mucosal epithelial cells were removed and that the decellularized trachea had lower immunogenicity than the control group. The analysis of SEM revealed that the decellularized trachea retained the micro- and ultra-structural architectures of the trachea and that the matrices cross-linked with genipin were denser. The biocompatibility evaluation and in vivo implantation experiments showed that the decellularized trachea treated with the DEM had better biocompatibility than that treated with the TPM and that immunogenicity in the cross-linked tissues was lower than that in the uncross-linked tissues (p\0.05). CONCLUSIONS: Compared with the trachea treated with the TPM, the rabbit trachea processed by the DEM had better biocompatibility and lower immunogenicity, and its structural and mechanical characteristics were effectively improved after the genipin treatment, which is suitable for engineering replacement tracheal tissue.

Study on the constitutive behavior and hot deformation characteristic of Mg-4Sm-2Zn-0.5Zr alloy

Zhong-Yi Cai,Chao-jie Che,Ruo-Han Chang,Li-Ren Cheng,Qing-Min Chen 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.20 No.3

Mg–4Sm–2Zn–0.5Zr alloy is a new type of heat-resistant magnesium alloy, it has the mechanical properties similar to EZ33 alloy but is much cheaper than EZ33 in cost since Samarium (Sm) rather than Nd was employed in the alloy. In this paper, based on isothermal compression tests in the temperature range of 350–450 °C and strain rate range of 0.001–1.0 s−1, the Arrhenius-type constitutive equations for this alloy were established, and the hot working flow behavior and the microstructures of the alloy were examined. To evaluate the hot deformation mechanisms and determine the optimal processing parameters, 3D processing maps under different deformation conditions were developed according to the dynamic material model and Muthy instability criterion. The hot extrusion experiments were carried out, and the results show the predictions of processing maps are in agreement with the experimental results.

Numerical Study of Ion Orbits in EAST Plasmas with a Current-reversal Equilibrium Configuration

Yi-jun Zhong,Xue-yu Gong,Ye-ming Hu,Xin-xia Li 한국물리학회 2015 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.66 No.11

By solving the Grad-Shafranov equation in the cylindrical coordinate system, we numerically obtain the tokamak plasma equilibrium configurations of the conventional mode and the high-to-lowfield- side current-reversal equilibrium mode (HL-CREC) by using the discharge parameters for the Experimental Advanced Superconductor Tokamak (EAST). By coupling with the particle’s motion equation, we obtain the orbits of trapped particles and passing particles under both equilibrium configurations. We find that the orbit of the passing particle in the HL-CREC is wholly confined on the low-field side and that the half width of the banana orbit of trapped particles increases greatly compared with those in the conventional equilibrium configuration. In addition, the ion loss is studied based on the Monte Carlo method. The results show that for ions near the plasma edge, a much high ion loss rate can be obtained in HL-CREC than that in the conventional equilibrium configuration.

A Method for generating simulation data to predict the processing capability of container terminals

Zhong Yi,Muhammad Tayyab Ali,Bonghee Hong 한국정보과학회 2020 한국정보과학회 학술발표논문집 Vol.2020 No.7