Mechanism and kinetics of esterification of adipic acid and ethylene glycol by tetrabutyl titanate catalyst

Liwei Chen,Jumei Xu,Weilan Xue,Zuoxiang Zeng 한국화학공학회 2018 Korean Journal of Chemical Engineering Vol.35 No.1

An eight-step mechanism of esterification reaction between adipic acid (AA) and ethylene glycol (EG) catalyzed by tetrabutyl titanate [Ti(OBu)4] was studied in detail. The kinetic data for the esterification reaction between AA and EG catalyzed by tetrabutyl titanate [Ti(OBu)4] were measured in the temperature range of 403 K-433 K. A second- order kinetic model was established, and the model parameters were obtained through an optimization procedure by minimizing the value differences between the simulated component concentrations in the reaction system with the experimental ones. The results demonstrate that the model is suitable for the esterification reaction between AA and EG catalyzed by tetrabutyl titanate [Ti(OBu)4]. Furthermore, the esterification reaction rate increases with the increase of reaction temperature, concentration of catalyst and the initial reactant ratio of EG to AA.

Study on Optimal Design of Digital Music Player Based on Human-computer Interaction

Yan Chen,Min Lv,LiWei Guo 보안공학연구지원센터(IJSIP) 2015 International Journal of Signal Processing, Image Vol.8 No.1

Through the application of theories and principles of human-computer interaction design system, deficiencies on interaction of digital music player are analyzed; and through the analysis on cognitive features for interaction, hierarchy of needs, and emotional information of target users, the key factors and the relevant data that influence the objective of interaction design are researched, thus facilitating the modern digital music products design to follow up users’ physical and mental requirements, balancing the interaction design between human, computer and environment, bringing users more convenient and effective operation and experience, and providing more important theoretical thought and implementation process for humanized design.

Panax ginseng total protein promotes proliferation and secretion of collagen in NIH/3T3 cells by activating extracellular signal-related kinase pathway

Chen, Xuenan,Wang, Manying,Xu, Xiaohao,Liu, Jianzeng,Mei, Bing,Fu, Pingping,Zhao, Daqing,Sun, Liwei The Korean Society of Ginseng 2017 Journal of Ginseng Research Vol.41 No.3

Background: Recently, protein from ginseng was studied and used for the treatment of several kinds of diseases. However, the effect of ginseng total protein (GTP) on proliferation and wound healing in fibroblast cells remains unclear. Methods: In this study, cell viability was analyzed using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. Cell cycle distribution was analyzed by flow cytometer. The levels of transforming growth factor ${\beta}1$, vascular endothelial growth factor, and collagens were analyzed by enzyme-linked immunosorbent assay and immunofluorescence staining. The expressions of cyclin A, phosphorylation of extracellular signal-related kinase (p-ERK1/2), and ERK1/2 were analyzed by Western blotting. Results: Our results showed that GTP promoted cell proliferation and increased the percentage of cells in S phase through the upregulation of cyclin A in NIH/3T3 cells. We also found that GTP induced the secretion of type I collagen, and promoted the expression of other factors that regulate the synthesis of collagen such as transforming growth factor ${\beta}1$ and vascular endothelial growth factor. In addition, the phosphorylation of ERK1/2 at Thr202/Tyr204 was also increased by GTP. Conclusion: Our studies suggest that GTP promoted proliferation and secretion of collagen in NIH/3T3 cells by activating the ERK signal pathway, which shed light on a potential function of GTP in promoting wound healing.

Panax ginseng total protein promotes proliferation and secretion of collagen in NIH/3T3 cells by activating extracellular signal-related kinase pathway

Xuenan Chen,Manying Wang,Xiaohao Xu,Jianzeng Liu,Bing Mei,Pingping Fu,Da-Qing Zhao,Liwei Sun 고려인삼학회 2017 Journal of Ginseng Research Vol.41 No.3

Background: Recently, protein from ginseng was studied and used for the treatment of several kinds of diseases. However, the effect of ginseng total protein (GTP) on proliferation and wound healing in fibroblast cells remains unclear. Methods: In this study, cell viability was analyzed using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide] assay. Cell cycle distribution was analyzed by flow cytometer. The levels of transforming growth factor b1, vascular endothelial growth factor, and collagens were analyzed by enzyme-linked immunosorbent assay and immunofluorescence staining. The expressions of cyclin A, phosphorylation of extracellular signal-related kinase (p-ERK1/2), and ERK1/2 were analyzed byWestern blotting. Results: Our results showed that GTP promoted cell proliferation and increased the percentage of cells in S phase through the upregulation of cyclin A in NIH/3T3 cells. We also found that GTP induced the secretion of type I collagen, and promoted the expression of other factors that regulate the synthesis of collagen such as transforming growth factor b1 and vascular endothelial growth factor. In addition, the phosphorylation of ERK1/2 at Thr202/Tyr204 was also increased by GTP. Conclusion: Our studies suggest that GTP promoted proliferation and secretion of collagen in NIH/3T3 cells by activating the ERK signal pathway, which shed light on a potential function of GTP in promoting wound healing.

Integrated risk assessment method for spent fuel road transportation accident under complex environment

Tao, Longlong,Chen, Liwei,Long, Pengcheng,Chen, Chunhua,Wang, Jin Korean Nuclear Society 2021 Nuclear Engineering and Technology Vol.53 No.2

Current risk assessment of Spent Nuclear Fuel (SNF) transportation has the problem of the incomplete risk factors consideration and the general particle diffusion model utilization. In this paper, the accident frequency calculation and the detailed simulation of the accident consequences are coupled by the integrated risk assessment method. The "man-machine-environment" three-dimensional comprehensive risk indicator system is established and quantified to characterize the frequency of the transportation accidents. Consideration of vegetation, building and turbulence effect, the standard k-ε model is updated to simulate radioactive consequence of leakage accidents under complex terrain. The developed method is applied to assess the risk of the leakage accident in the scene of the typical domestic SNF Road Transportation (SNFRT). The critical risk factors and their impacts on the dispersion of the radionuclide are obtained.

Application of Travel Management System Based on Route Inquiry

Shiyu Wang,Liwei Chen 보안공학연구지원센터 2015 International Journal of Smart Home Vol.9 No.6

The traditional tourism system’s information inquiry is incomplete, images are not intuitive and the results are not three-dimensional. In order to solve these problems, this paper proposes system management design and application based on tourist routes inquiry. Firstly, based on MAP technology, it achieves a cross-check of space and attribute data, then explores the knapsack problem through the genetic algorithm, making the travel route arrangements more reasonable and providing latest shareable maps for tourists, and finally conducts simulation experiment on system model. The results show that compared with the traditional one, this tourism management system’s information inquiry is faster, and also its inquiry results are more three-dimensional and visual. It is much more convenient for tourists with practicality.

Proteomic analysis of amino acid metabolism differences between wild and cultivated Panax ginseng

Hang Sun,Fangbing Liu,Liwei Sun,Jianzeng Liu,Manying Wang,Xuenan Chen,Xiaohao Xu,Rui Ma,Kai Feng,Rui Jiang 고려인삼학회 2016 Journal of Ginseng Research Vol.40 No.2

Background: The present study aimed to compare the relative abundance of proteins and amino acid metabolites to explore the mechanisms underlying the difference between wild and cultivated ginseng (Panax ginseng Meyer) at the amino acid level. Methods: Two-dimensional polyacrylamide gel electrophoresis and isobaric tags for relative and absolute quantitation were used to identify the differential abundance of proteins between wild and cultivated ginseng. Total amino acids in wild and cultivated ginseng were compared using an automated amino acid analyzer. The activities of amino acid metabolism-related enzymes and the contents of intermediate metabolites between wild and cultivated ginseng were measured using enzyme-linked immunosorbent assay and spectrophotometric methods. Results: Our results showed that the contents of 14 types of amino acids were higher in wild ginseng compared with cultivated ginseng. The amino acid metabolism-related enzymes and their derivatives, such as glutamate decarboxylase and S-adenosylmethionine, all had high levels of accumulation in wild ginseng. The accumulation of sulfur amino acid synthesis-related proteins, such as methionine synthase, was also higher in wild ginseng. In addition, glycolysis and tricarboxylic acid cycle-related enzymes as well as their intermediates had high levels of accumulation in wild ginseng. Conclusion: This study elucidates the differences in amino acids between wild and cultivated ginseng. These results will provide a reference for further studies on the medicinal functions of wild ginseng.

Hierarchical porous ECM scaffolds incorporating GDF-5 fabricated by cryogenic 3D printing to promote articular cartilage regeneration

Wu Jiang,Fu Liwei,Yan Zineng,Yang Yu,Yin Han,Li Pinxue,Yuan Xun,Ding Zhengang,Kang Teng,Tian Zhuang,Liao Zhiyao,Tian Guangzhao,Ning Chao,Li Yuguo,Sui Xiang,Chen Mingxue,Liu Shuyun,Guo Quanyi 한국생체재료학회 2023 생체재료학회지 Vol.27 No.00

In recent years, there has been significant research progress on in situ articular cartilage (AC) tissue engineering with endogenous stem cells, which uses biological materials or bioactive factors to improve the regeneration microenvironment and recruit more endogenous stem cells from the joint cavity to the defect area to promote cartilage regeneration.In this study, we used ECM alone as a bioink in low-temperature deposition manufacturing (LDM) 3D printing and then successfully fabricated a hierarchical porous ECM scaffold incorporating GDF-5.Comparative in vitro experiments showed that the 7% ECM scaffolds had the best biocompatibility. After the addition of GDF-5 protein, the ECM scaffolds significantly improved bone marrow mesenchymal stem cell (BMSC) migration and chondrogenic differentiation. Most importantly, the in vivo results showed that the ECM/GDF-5 scaffold significantly enhanced in situ cartilage repair.In conclusion, this study reports the construction of a new scaffold based on the concept of in situ regeneration, and we believe that our findings will provide a new treatment strategy for AC defect repair.

Feasibility of Three-Dimensional Balanced Steady-State Free Precession Cine Magnetic Resonance Imaging Combined with an Image Denoising Technique to Evaluate Cardiac Function in Children with Repaired Tetralogy of Fallot

Peng YaFeng,Su XinYu,Hu LiWei,Wang Qian,Ouyang RongZhen,Sun AiMin,Guo Chen,Yao XiaoFen,Zhang Yong,Wang LiJia,Zhong YuMin 대한영상의학회 2021 Korean Journal of Radiology Vol.22 No.9

Objective: To investigate the feasibility of cine three-dimensional (3D) balanced steady-state free precession (b-SSFP) imaging combined with a non-local means (NLM) algorithm for image denoising in evaluating cardiac function in children with repaired tetralogy of Fallot (rTOF). Materials and Methods: Thirty-five patients with rTOF (mean age, 12 years; range, 7–18 years) were enrolled to undergo cardiac cine image acquisition, including two-dimensional (2D) b-SSFP, 3D b-SSFP, and 3D b-SSFP combined with NLM. End-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), and ejection fraction (EF) of the two ventricles were measured and indexed by body surface index. Acquisition time and image quality were recorded and compared among the three imaging sequences. Results: 3D b-SSFP with denoising vs. 2D b-SSFP had high correlation coefficients for EDV, ESV, SV, and EF of the left (0.959– 0.991; p < 0.001) as well as right (0.755–0.965; p < 0.001) ventricular metrics. The image acquisition time ± standard deviation (SD) was 25.1 ± 2.4 seconds for 3D b-SSFP compared with 277.6 ± 0.7 seconds for 2D b-SSFP, indicating a significantly shorter time with the 3D than the 2D sequence (p < 0.001). Image quality score was better with 3D b-SSFP combined with denoising than with 3D b-SSFP (mean ± SD, 3.8 ± 0.6 vs. 3.5 ± 0.6; p = 0.005). Signal-to-noise ratios for blood and myocardium as well as contrast between blood and myocardium were higher for 3D b-SSFP combined with denoising than for 3D b-SSFP (p < 0.05 for all but septal myocardium). Conclusion: The 3D b-SSFP sequence can significantly reduce acquisition time compared to the 2D b-SSFP sequence for cine imaging in the evaluation of ventricular function in children with rTOF, and its quality can be further improved by combining it with an NLM denoising method.

Proteomic analysis of amino acid metabolism differences between wild and cultivated Panax ginseng

Sun, Hang,Liu, Fangbing,Sun, Liwei,Liu, Jianzeng,Wang, Manying,Chen, Xuenan,Xu, Xiaohao,Ma, Rui,Feng, Kai,Jiang, Rui The Korean Society of Ginseng 2016 Journal of Ginseng Research Vol.40 No.2

Background: The present study aimed to compare the relative abundance of proteins and amino acid metabolites to explore the mechanisms underlying the difference between wild and cultivated ginseng (Panax ginseng Meyer) at the amino acid level. Methods: Two-dimensional polyacrylamide gel electrophoresis and isobaric tags for relative and absolute quantitation were used to identify the differential abundance of proteins between wild and cultivated ginseng. Total amino acids in wild and cultivated ginseng were compared using an automated amino acid analyzer. The activities of amino acid metabolism-related enzymes and the contents of intermediate metabolites between wild and cultivated ginseng were measured using enzyme-linked immunosorbent assay and spectrophotometric methods. Results: Our results showed that the contents of 14 types of amino acids were higher in wild ginseng compared with cultivated ginseng. The amino acid metabolism-related enzymes and their derivatives, such as glutamate decarboxylase and S-adenosylmethionine, all had high levels of accumulation in wild ginseng. The accumulation of sulfur amino acid synthesis-related proteins, such as methionine synthase, was also higher in wild ginseng. In addition, glycolysis and tricarboxylic acid cycle-related enzymes as well as their intermediates had high levels of accumulation in wild ginseng. Conclusion: This study elucidates the differences in amino acids between wild and cultivated ginseng. These results will provide a reference for further studies on the medicinal functions of wild ginseng.