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Your search keyword '"Li, Yan-Feng"' showing total 99 results
Start Over Author "Li, Yan-Feng" Publisher elsevier bv
99 results on '"Li, Yan-Feng"'

22. Epigenetic Inactivation of SOX30 Is Associated with Male Infertility and Offers a Therapy Target for Non-obstructive Azoospermia

Author

Han, Fei, primary, Jiang, Xiao, additional, Li, Zhi-ming, additional, Zhuang, Xuan, additional, Zhang, Xi, additional, Ouyang, Wei-ming, additional, Liu, Wen-bin, additional, Mao, Cheng-yi, additional, Chen, Qing, additional, Huang, Chuan-shu, additional, Gao, Fei, additional, Cui, Zhi-hong, additional, Ao, Lin, additional, Li, Yan-feng, additional, Cao, Jia, additional, and Liu, Jin-yi, additional

Published
2020
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30. Iron-embedded boron nitride nanosheet as a promising electrocatalyst for the oxygen reduction reaction (ORR): A density functional theory (DFT) study

Author

Yue-jie Liu, Jingxiang Zhao, and Li-yan Feng

Subjects
Renewable Energy, Sustainability and the Environment, Energy Engineering and Power Technology, Electrocatalyst, Catalysis, Gibbs free energy, chemistry.chemical_compound, symbols.namesake, Chemical engineering, chemistry, Boron nitride, Computational chemistry, Atom, symbols, Molecule, Density functional theory, Electrical and Electronic Engineering, Physical and Theoretical Chemistry, Nanosheet
Abstract

We performed comprehensive density functional theory (DFT) calculations to explore the possibility of the Fe-embedded hexagonal boron nitride ( h -BN) sheet as a novel electrocatalyst for ORR. Our results show that Fe atom can strongly bind with defective BN sheet and thus ensure its high stability. Moreover, O 2 molecule is found to be strongly chemisorbed on Fe-embedded BN sheet with the adsorption energy of −1.76 eV, which can server as precursors for ORR, followed by its hydrogenation into OOH species rather than direct breakage of the O–O bond. Further, the HOOH species in the process of OOH reduction is shown to be unstable and dissociates into two OH group, suggesting that ORR catalyzed by Fe-embedded BN sheet is a direct four-electron pathway. Finally, on the basis of the calculations on the free energy change and activate energy of each step in ORR, we expect that Fe-embedded BN sheet exhibits good catalytic activity for ORR. Our results provide an useful guidance for the design and fabrication of novel and nonprecious BN sheet-based electrocatalyst for ORR as the alternative of expensive Pt catalysts.

Published
2015

43. A Computational Study on Structural Barrier to Vertical Spread of Window Spill Plume along Building Exterior Facade

Author

Zhang Jing-yan, Xing Xue-fei, and Li Yan-feng

Subjects
Vertical spread, balcony, Engineering, Structural barrier, business.industry, Fire prevention, Full scale, Window (geology), General Medicine, Structural engineering, Plume, Facade, Fire room, window, business, window spill plume, Engineering(all), windowsill wall
Abstract

The barrier effect of window, windowsill wall and balcony is significant on vertical spread of window spill plume along building exterior facade. Fire Simulation experiments are conducted in a full scale model, consisting one 4m x 4m x 4m fire compartment with five windows, five windowsill walls and five balconies like geometries in order to observe vertical spread of window spill plume along building exterior facade under different dimensions of windows, windowsill walls and balconies, and then the correlation between smoke temperature near the exterior facade and dimensions of window, windowsill wall and balcony is obtained by numerical fitting and dimensional analyses. Finally concluded:(l) window, windowsill wall and balcony play different degrees of barrier effect on vertical spread of window spill plume along building exterior facade, balcony playing dominant barrier effect; (2) When the elongation of the balcony is not less than 1.2m, the critical hazardous temperature (70 ‘C) does not spread to the exterior facade of fire room upper; (3) When the width of the window is less than 2.4m, the critical hazardous temperature does not spread to the exterior facade of fire room upper. These quantitative conclusions provide fire Prevention of the building exterior facade with a reference.

Published
2013
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44. Inhibition of topoisomerase II by 8-chloro-adenosine triphosphate induces DNA double-stranded breaks in 8-chloro-adenosine-exposed human myelocytic leukemia K562 cells

Author

Hong-Ti Jia, Li-Yan Feng, Xiu-Zhen Jia, Ju-Hua Ni, Shu-Yan Li, Guo-Shun An, and Sheng-Yong Yang

Subjects
Pharmacology, chemistry.chemical_classification, 2-Chloroadenosine, DNA synthesis, Hydrolysis, Topoisomerase, Biology, Biochemistry, Molecular biology, chemistry.chemical_compound, Adenosine Triphosphate, Enzyme, chemistry, Leukemia, Myeloid, ATP hydrolysis, Kinetoplast, Cancer cell, Biocatalysis, biology.protein, Humans, Topoisomerase II Inhibitors, K562 Cells, DNA, DNA Damage, K562 cells
Abstract

8-Chloro-cAMP and 8-chloro-adenosine (8-Cl-Ado) are known to inhibit proliferation of cancer cells by converting 8-Cl-Ado into an ATP analog, 8-chloro-ATP (8-Cl-ATP). Because type II topoisomerases (Topo II) are ATP-dependent, we infer that 8-Cl-Ado exposure might interfere with Topo II activities and DNA metabolism in cells. We found that 8-Cl-Ado exposure inhibited Topo II-catalytic activities in K562 cells, as revealed by decreased relaxation of the supercoiled pUC19 DNA and inhibited decatenation of the kinetoplast DNA (kDNA). In vitro assays showed that 8-Cl-ATP, but not 8-Cl-Ado, could directly inhibit Topo IIalpha-catalyzed relaxation and decatenation of substrate DNA. Furthermore, 8-Cl-ATP inhibited Topo II-catalyzed ATP hydrolysis and increased salt-stabilized closed clamp. In addition, 8-Cl-Ado exposure decreased bromo-deoxyuridine (BrdU) incorporation into DNA and led to enhanced DNA double-stranded breaks (DSBs) and to increased formation of gamma-H2AX nuclear foci in exposed K562 cells. Together, 8-Cl-Ado/8-Cl-ATP can inhibit Topo II activities in cells, thereby inhibiting DNA synthesis and inducing DNA DSBs, which may contribute to 8-Cl-Ado-inhibited proliferation of cancers.

Published
2009

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