http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Li Ming,Yin Liming,Wu Lili,Zhu Yunsen,Wang Xi 대한독성 유전단백체 학회 2020 Molecular & cellular toxicology Vol.16 No.4
Background Paclitaxel is a chemotherapeutic drug for cancer, which is isolated from the Pacifc yew tree. However, and the molecular mechanism and the antitumor efects of paclitaxel on osteosarcoma cell remain to be explored. Objective The aim of our study was to explore the possible molecular mechanisms of apoptosis in osteosarcoma induced by paclitaxel. Results Paclitaxel can obviously decrease the proliferation of HOS-732 cells in a dose-dependent manner. Paclitaxel could induce the cell cycle arrest at the G2/M-phase and decreases the CDK5 and CCNE1 expression in HOS-732 cells. Paclitaxel promotes cell apoptosis in HOS-732 cells, which may be contacted to the decreasing of Bcl-2 protein expression. Further, the production of ROS in HOS-732 cells was remarkably increased with the increasing concentration of paclitaxel. Moreover, paclitaxel induces the ER-stress related gene and protein expression (GRP79, DDIT3 mRNA and GRP78, XBP-1 s, IRE1α protein expression) in osteosarcoma cells. Conclusion Paclitaxel can inhibit the proliferation of HOS-732 cells and increase ROS and ER-stress response to promote cell apoptosis, suggesting that paclitaxel may represent a new therapeutic option for the treatment and prevention osteosarcoma.
A Parametric and Accurate CAD Model of Flat End Mills Based on Its Grinding Operations
Liming Wang,Lin Kong,Jian-Feng Li,Zezhong Chen 한국정밀공학회 2017 International Journal of Precision Engineering and Vol.18 No.10
End mills are widely used in CNC machining. However, the complex structures of end mills make it difficult to define the CAD model which determines the quality and performance of virtual cutting tests. This paper presents an accurate CAD model of end mill through analyzing kinematic models of grinding processes. Initially, a common parametric representation of grinding wheel is given. Base on the given wheel profile and the design parameters of cutters including the rake angle, core diameters and pitch angle, the representation of helix flute surface is first calculated using contact theory and also the formulation of rake angle and pitch angle are investigated. Next, four design parameters are used to control the shape of the gash which is formed via Boolean operation between the given wheel and end mill. Similarly, the peripheral edges and end edges are swept using grinding simulation. Finally, integrating all the above processes, a parametric CAD model of end mill is represented. The simulation results showed that the proposed CAD model could achieve 1e-3 mm and 2e-2 deg. in accuracy, which can be used to evaluate the grinding process or improve the future FEA analysis of end-mills.
Liming Wang,Guoshan Zhang 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.3
This paper is devoted to the perfect tracking problem of output consensus for a class of non-identical fractional order multi-agent systems (NIFOMASs), in which different agents have different and unknown fractional orders and dynamic functions. For the NIFOMASs including one leader agent and multiple follower agents, by designing the event-triggered mechanism along an iteration axis and introducing it into the iterative learning controller, an event-triggered iterative learning consensus protocol is proposed to reduce the number of controller update and to save the communication resource. By analyzing the convergence of learning process, the sufficient conditions are derived to guarantee that the output consensus tracking can be perfectly achieved over the finite time interval as the iteration step goes to infinity. Finally, three numerical examples are presented to demonstrate the effectiveness and wide application scope of the proposed control strategy.
Jiatai Gu,Zhenzhen Quan,Liming Wang,Hongnan Zhang,Ni Wang,Xiaohong Qin,Rongwu Wang,Jianyong Yu 한국섬유공학회 2022 Fibers and polymers Vol.23 No.6
Membranes with the functions of waterproofness and breathability are of great interest due to their huge scientificand commercial value in many practical applications. However, designing such membranes with a desirable performance bysimple and efficient fabrication process remains a tremendous challenge. Herein, novel binary structured composite fibrousmembranes were developed for waterproof and breathable applications via simple one-step multi-jet electrospinningtechnology. This composite membranes were made up of polyvinylidene fluoride (PVDF) and polyacrylonitrile (PAN). PVDF was incorporated into the PAN fiber matrix as a modifier to improve the hydrophobic behavior of fibers. Meanwhile,PVDF microspheres/fibers were employed as building blocks to orderly embed in PAN/PVDF fiber framework, impartingthe composite membranes with fluffy micro-nano hierarchical structures. Consequently, with the integrated features of robusthydrophobicity as well as elaborate fiber-microsphere binary structure, the resultant composite membranes exhibitedsynergistically modest waterproof and breathable performances with the hydrostatic pressure of 18.04 kPa, water vaportransmittance (WVT) rate of 4.65 kg m-2 d-1, and air permeability of 64.19 mm s-1. This simple preparation process andunique composite structure may provide a new insight to design and fabricate waterproof and breathable membranes forvariously potential applications, including the protective clothing, separation membrane, and filter.
BCN Graphene as Efficient Metal‐Free Electrocatalyst for the Oxygen Reduction Reaction
Wang, Shuangyin,Zhang, Lipeng,Xia, Zhenhai,Roy, Ajit,Chang, Dong Wook,Baek, Jong‐,Beom,Dai, Liming WILEY‐VCH Verlag 2012 Angewandte Chemie Vol.124 No.17
<P><B>Einen einfachen Zugang</B> zu B,N‐dotiertem Graphen mit einstellbarer Zusammensetzung eröffnet das Tempern von Graphenoxid in Gegenwart von Borsäure und Ammoniak. Das gebildete BCN‐Graphen (siehe Bild; C grau, H weiß, B rosa, N blau) ist bei der Sauerstoffreduktion in alkalischem Milieu ein aktiverer Katalysator als kommerzielle Pt/C‐Elektrokatalysatoren.</P>
Liming Liu,Fei Liu,Disheng Fang,Hongyang Wang 한국정밀공학회 2015 International Journal of Precision Engineering and Vol. No.
Based on the idea of alloying welding seam, a series of Zn-30Al-xTi filler metal was used to join Mg/Al dissimilar metals by tungsten inert gas welding, where the x was 0, 0.05, 0.1, 0.5, and 1, respectively. The effect of various Ti content on the microstructure and the mechanical property of Mg-Al butt joints was investigated. Results indicated that the fusion zones of the joints were mainly composed of α-Al, MgZn2 and Al-Zn eutectics when the Ti content was 0.05, 0.1 and 0.5 wt.%, and Al3Ti compounds could precipitate first and act as nucleuses during solidification process when the Ti content was appropriate. The mechanical property of the weld joints improved consistently to the increasing content of Ti. The optimum average tensile strength of the joints reached 148 MPa when Zn-30Al-0.5Ti was used, but the average tensile strength decreased again when Zn-30Al-1Ti was used.
Polyelectrolyte-Functionalized Graphene as Metal-Free Electrocatalysts for Oxygen Reduction
Wang, Shuangyin,Yu, Dingshan,Dai, Liming,Chang, Dong Wook,Baek, Jong-Beom American Chemical Society 2011 ACS NANO Vol.5 No.8
<P>Poly(diallyldimethylammonium chloride), PDDA, was used as an electron acceptor for functionalizing graphene to impart electrocatalytic activity for the oxygen reduction reaction (ORR) in fuel cells. Raman and X-ray photoelectron spectroscopic measurements indicate the charge transfer from graphene to PDDA. The resultant graphene positively charged <I>via</I> intermolecular charge-transfer with PDDA was demonstrated to show remarkable electrocatalytic activity toward ORR with better fuel selectivity, tolerance to CO posing, and long-term stability than that of the commercially available Pt/C electrode. The observed ORR electrocatalytic activity induced by the intermolecular charge-transfer provides a general approach to various carbon-based metal-free ORR catalysts for oxygen reduction.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2011/ancac3.2011.5.issue-8/nn200879h/production/images/medium/nn-2011-00879h_0008.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn200879h'>ACS Electronic Supporting Info</A></P>
Study on the combustion process and work capacity of a micro free-piston engine
Qian Wang,Liming Dai,Kai Wu,Jin Bai,Zhixia He 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.11
With the main idea of exploring combustion conditions and the work capacity of the micro free-piston engine, the study concern isvisualization work including Homogeneous charge compression ignition (HCCI) combustion in the micro-chamber. The initial freepistonvelocity was adjusted to achieve a wide range of compression ratio. The combustion characteristics, the piston motion and pressurevariations under different compression ratios were discussed. Results indicate that the critical combustion condition occurs when thecompression ratio rises to a certain degree. Two-stage combustion characteristics can be observed in micro HCCI combustion processeswith the fuel of the DME/oxygen mixture. The micro-chamber pressure increases with the increase of the compression ratio. The criticalpeak pressure of 5.4 MPa is obtained when the initial piston velocity reaches 15.0 m/s and the diameter and the length of the microchamberis 3 mm and 37 mm, respectively.