A review of approaches for the design of high-performance metal/ graphene electrocatalysts for fuel cell applications

Jiamin Liu,최형진,Long-Yue Meng 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.64 No.-

Metal/graphene electrocatalysts have attracted growing attention in recent years due to their highcatalyst loadings, good activity, and high stabilities. In this review, we summarize various approachestowards improving the efficiencies of metal/graphene electrocatalysts in terms of both cost andperformance, based on optimization of the graphene support and the metal catalyst particles themselves. Thus, four different approaches are examined: (1) increasing the catalyst/support binding energy, (2)inducing additional anchoring and active sites, (3) enlarging the effective catalyst surface areas, and (4)enhancing the intrinsic catalytic activity through modification of the electronic structure. Finally,remarks on necessary future work in this area will be given in the context of producing metal/grapheneelectrocatalysts better suited to fuel cell applications.

Synthesis of Polypyrrole-based Nitrogen-containing Porous Carbon Nanotubes for CO2 Adsorption

Jiamin Liu,Biao Jin,Long-Yue Meng,Kyung-Hee Lee 한국탄소학회 2018 Carbon Letters Vol.28 No.-

Identification and differential expression of microRNAs in Madin–Darby canine kidney cells with high and low tumorigenicities

Wang Jiamin,Liu Lixia,Yang Di,Zhang Li,Abudureyimu Ayimuguli,Qiao Zilin,Ma Zhongren 한국유전학회 2022 Genes & Genomics Vol.44 No.2

Background: Madin-Darby canine kidney (MDCK) cells are widely used for vaccine production, however, the safety of MDCK cells needs to be considered seriously because of high tumorigenicity. Micro RNAs (miRNAs) that are involved in the tumorigenicity of MDCK cells have been never been reported. Objective: To reveal the role of miRNA in the tumorigenic phenotype of MDCK cell line. Methods: The miRNA expression profiles of two monoclonal MDCK cells (M09CL and M35CL) with low tumorigenicity and one MDCK cell line (M73P) with high tumorigenicity were characterized and investigated by using small RNA-seq technology. Results: A total of 5 known miRNAs and 5 novel miRNAs were highly expressed in M73P. In addition, 4 known miRNAs and 4 novel miRNAs were highly expressed in M09CL and M35CL. The target genes of the differentially expressed miRNAs were significantly enriched in several biological processes, and the majority of these genes were involved in pathways in cancer and the MAPK signaling pathway. Through interaction analysis, 4 up-regulated miRNAs (cfa-miR-452, cfa-miR-8826, cfa-miR-224, and cfa-miR-2387) and their crucial target genes related to the tumor regulation network were identified. Results indicated these 4 miRNAs might play crucial roles in the tumorigenesis of MDCK cells. Conclusion: Our findings, which were based on the functional prediction of miRNAs and target genes, suggested that miRNAs might influence the tumorigenicity of MDCK cells by regulating target genes. Moreover, the results provided important data for understanding the miRNA-mediated regulatory networks that control the tumorigenicities of MDCK cells.

Ginsenosides Rg1 regulate lipid metabolism and temperature adaptation in Caenorhabditis elegans

Hao Shi,Jiamin Zhao,Yiwen Li,Junjie Li,Yunjia Li,Jia Zhang,Zhantu Qiu,Chaofeng Wu,Mengchen Qin,Chang Liu,Zhiyun Zeng,Chao Zhang,Lei Gao 고려인삼학회 2023 Journal of Ginseng Research Vol.47 No.4

Nickel‑based N/S‑dual doped graphene/carbon nanotubes electrocatalyst for oxygen evolution

Jin‑Chi Jiang,Jiamin Liu,Yingai Piao,Mei‑Shan Zhang,Long‑Yue Meng 한국탄소학회 2023 Carbon Letters Vol.33 No.1

Hydrogen energy is a promising source of renewable and clean energy for various industries, such as chemical, automobile, and energy industries. Electrolysis of water is one of the basic methods for the production of hydrogen energy. However, the high overpotential of the oxygen evolution reaction (OER) in water electrolysis has hindered the effective production of hydrogen using this method. Thus, the development of high-efficiency non-precious metal-based electrocatalysts for OER is extremely significant. In this study, we adopted a one-step hydrothermal method to fabricate Ni-based catalysts with N/Sdual doped graphene oxide/carbon nanotube (GO/CNT) supports using thiourea ( CH4N2S) and urea as the S source and the N source. It was observed that the amount of thiourea utilized in the synthesis of the catalyst affected the morphology, composition, and the electrochemical properties of the catalyst. For a GO/CNT-to-thiourea mass ratio of 1:10, the catalyst exhibited the highest activity, where the OER overpotential was 320 mV at a current density of 10 mA/cm2. This was attributed to the high specific surface area, high conductivity, and fast electron transport channels of the N/S-dual doped GO/ CNT composite. Furthermore, sulfurization of the Ni particles to form nickel sulfide played a significant role in enhancing the catalytic performance.

Sciatic nerve leachate of cattle causes neuronal differentiation of PC12 cells via ERK1/2 signaling pathway

Ziqiang Zhang,Yumei Liu,Xuemin Zhu,Lan Wei,Jiamin Zhu,Ke Shi,Guotao Wang,Li Pan 대한수의학회 2018 Journal of Veterinary Science Vol.19 No.4

Previous studies have shown that the sciatic nerve has neurotrophic activity, and nerve regeneration, differentiation, and axon outgrowth can be modulated by different sciatic nerve preparations. However, numerous animals may have to be sacrificed to obtain enough sciatic nerves to make a sciatic nerve preparation. Some studies have demonstrated that the role of sciatic nerve preparations in neural differentiation depends on the neurotrophins that Schwann cells secrete, and these factors are highly conserved among different species. To reduce the use of experimental animals, in this study, we made a leachate by using the sciatic nerve of cattle and explored its effect on neuronal differentiation of rat PC12 cells (a useful model for studying neuronal differentiation). Results showed the neurite outgrowth of PC12 cells treated with the cattle sciatic nerve leachate for 3, 6, and 9 days was significantly improved, and the expressions of β3-tubulin and microtubule-associated protein 2 (two neuron-specific proteins) were increased. Moreover, the ERK1/2 signaling pathway was activated after PC12 cells were incubated with cattle sciatic nerve leachate for 9 days. Thus, a sciatic nerve leachate obtained from cattle can effectively induce neuronal differentiation of rat PC12 cells via ERK1/2 signaling pathway.

Identification of Transmembrane Domain of a Membrane Associated Protein NS5 of Dendrolimus punctatus Cytoplasmic Polyhedrosis Virus

Chen, Wuguo,Zhang, Jiamin,Dong, Changjin,Yang, Bo,Li, Yanqiu,Liu, Chuanfeng,Hu, Yuanyang Korean Society for Biochemistry and Molecular Biol 2006 Journal of biochemistry and molecular biology Vol.39 No.4

We examined the intracellular localization of NS5 protein of Dendrolimus punctatus cytoplasmic polyhedrosis virus (DpCPV) by expressing NS5-GFP fusion protein and proteins from deletion mutants of NS5 in baculovirus recombinant infected insect Spodoptera frugiperda (Sf-9) cells. It was found that the NS5 protein was present at the plasma membrane of the cells, and that the N-terminal portion of the protein played a key role in the localization. A transmembrane region was identified to be present in the N-terminal portion of the protein, and the detailed transmembrane domain (SQIHMVWVKSGLVFF, 57-71aa) of N-terminal portion of NS5 was further determined, which was accorded with the predicted results, these findings suggested that NS5 might have an important function in viral life cycle.

Hybrid phase-shifted modulation method for hybrid cascaded H-bridge inverters

Hu, Wenhua,Guo, Jiamin,Liu, Jianfeng,Yuan, Yisheng The Korean Institute of Power Electronics 2021 JOURNAL OF POWER ELECTRONICS Vol.21 No.10

Due to its unreasonable DC voltage distribution, the phase-shifted pulse width modulation (PS-PWM) method cannot be directly applied to equal-ratio and equal-difference hybrid CHB inverters. Thus, these types of inverters lose the double-frequency characteristic of the CHB topology. To preserve this double-frequency characteristic, reduce the switching frequency of the high-voltage cells, and simplify the modulation method. This article proposes an optimized topology for the hybrid CHB inverter by optimizing the distribution of the DC voltage. A hybrid PS-PWM method is also proposed by combing the step-wave modulation method and the PS-PWM method. Theoretical analysis, simulation analysis, and experimental results show that the optimized topology and the hybrid PS-PWM method are both valid and feasible.

Define of Optimal Addition Period of Osteogenic Peptide to Accelerate the Osteogenic Differentiation of Human Pluripotent Stem Cells

Song Yameng,Li Hongjiao,Wang Zixuan,Shi Jiamin,Li Jing,Wang Lu,Liao Lingzi,Ma Shengqin,Zhang Yun,Liu Bin,Yang Yaling,Zhou Ping 한국조직공학과 재생의학회 2024 조직공학과 재생의학 Vol.21 No.2

Background: The addition of growth factiors is commonly applied to improve the osteogenic differentiation of stem cells. However, for human pluripotent stem cells (hPSCs), their complex differentiation processes result in the unknown effect at different stages. In this study, we focused on the widely used bone forming peptide-1 (BFP-1) and investigated the effect and mechanisms of its addition on the osteogenic induction of hPSCs as a function of the supplementation period. Methods: Monolayer-cultured hPSCs were cultured in osteogenic induction medium for 28 days, and the effect of BFP-1 peptide addition at varying weeks was examined. After differentiation for varying days (0, 7, 14, 21 and 28), the differentiation efficiency was determined by RT–PCR, flow cytometry, immunofluorescence, and alizarin red staining assays. Moreover, the expression of marker genes related to germ layers and epithelial-mesenchymal transition (EMT) was investigated at day 7. Results: Peptide treatment during the first week promoted the generation of mesoderm cells and mesenchymal-like cells from hiPSCs. Then, the upregulated expression of osteogenesis marker genes/proteins was detected in both hESCs and hiPSCs during subsequent inductions with BFP-1 peptide treatment. Fortunately, further experimental design confirmed that treating the BFP-1 peptide during 7–21 days showed even better performance for hESCs but was ineffective for hiPSCs. Conclusion: The differentiation efficiency of cells could be improved by determining the optimal treatment period. Our study has great value in maximizing the differentiation of hPSCs by adding osteogenesis peptides based on the revealed mechanisms and promoting the application of hPSCs in bone tissue regeneration. Background: The addition of growth factiors is commonly applied to improve the osteogenic differentiation of stem cells. However, for human pluripotent stem cells (hPSCs), their complex differentiation processes result in the unknown effect at different stages. In this study, we focused on the widely used bone forming peptide-1 (BFP-1) and investigated the effect and mechanisms of its addition on the osteogenic induction of hPSCs as a function of the supplementation period. Methods: Monolayer-cultured hPSCs were cultured in osteogenic induction medium for 28 days, and the effect of BFP-1 peptide addition at varying weeks was examined. After differentiation for varying days (0, 7, 14, 21 and 28), the differentiation efficiency was determined by RT–PCR, flow cytometry, immunofluorescence, and alizarin red staining assays. Moreover, the expression of marker genes related to germ layers and epithelial-mesenchymal transition (EMT) was investigated at day 7. Results: Peptide treatment during the first week promoted the generation of mesoderm cells and mesenchymal-like cells from hiPSCs. Then, the upregulated expression of osteogenesis marker genes/proteins was detected in both hESCs and hiPSCs during subsequent inductions with BFP-1 peptide treatment. Fortunately, further experimental design confirmed that treating the BFP-1 peptide during 7–21 days showed even better performance for hESCs but was ineffective for hiPSCs. Conclusion: The differentiation efficiency of cells could be improved by determining the optimal treatment period. Our study has great value in maximizing the differentiation of hPSCs by adding osteogenesis peptides based on the revealed mechanisms and promoting the application of hPSCs in bone tissue regeneration.

Numerical study of conjugate heat transfer of steam and air in high aspect ratio rectangular ribbed cooling channel

Tieyu Gao,Jiangnan Zhu,Changwei Liu,Jiamin Xu 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.3

The relationship between flow field and heat transfer in an air/steam cooled ribbed channel was numerically investigated and compared. The width to height ratio was 4 and the rib height to hydraulic diameter was 0.078. The conjugate heat transfer method was adopted and a uniform heat source was located in the solid domain to simulate the actual heating method in the experiment. The GGI method was used to deal with the solid-fluid interface. The fluid field structure was shown by vortex core technology. We found that the wall heat flux distribution is similar with that of the Nusselt number, which is periodic. The temperature difference of a certain position on the inner and outer wall was less than 2 K. The Nusselt number reached its peak value at No.15-18 part and then decreased. The large width to height ratio led to strong interaction between the main flow fluid and the fluid in near wall region. As a result, an extra main flow secondary flow and two separation vortexes could be observed. These three additional vortexes were all in main flow region. The two separation vortexes approached to each other in flow direction and mixed into one vortex at low Reynolds number. When Reynolds number is larger than 30000, the two vortexes remain independent. The relative distance between them reaches the minimum value and the Nusselt number reaches the peak value at the same time. In addition, the flow field structure is mainly determined by Reynolds number and the fluid type cannot obviously influence the secondary flow distribution. The generation and separation of secondary flow as well as the mixing of secondary flows can enhance the local heat transfer strength.