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Defence Technology（防务技术） 2023年第6期24卷 46-57页

作者： jun-peng liu Hao-rui Zhang Qi-Long Yan Science and Technology on Combustion Internal Flow and Thermostructure LaboratoryNorthwestern Polytechnical UniversityXi'an 710071China

The characteristic of easy sintering of aluminum nanoparticle(ANP)limits its application in solid *** ANP with fluoropolymer could effectively improve its combustion *** find out how the coating layer inhibits sintering and promotes complete combustion of particles from an atomic view,a comparative study has been done for bare ANP and PTFE coated ANP by using reactive molecular dynamics *** sintering process is quantified by shrinkage ratio and gyration *** results show that,at the same heating rate and combustion temperatures,bare ANPs are sintered together after the temperature exceeds the melting point of aluminum but the decomposition of PTFE coating layer pushes particles away and increases reaction surface area by producing small Al-F *** sintering of ANPs which are heated in PTFE is alleviated compared with particles heated in oxygen,but particles still sinter together due to the lack of intimate contact between PTFE and alumina *** effect of temperature on the combustion of PTFE coated ANPs is also studied from 1000 to3500 *** number density analysis shows the particles will not be sintered at any *** fluoride prefers diffusing to the external space and the remained particles are mainly composed of Al,C and *** ignition simulations are performed by adopting micro canonical *** the expansion of aluminum core and the melting of alumina shell,bare ANPs are sintered into a liquid particle *** PTFE coated ANPs,the volatilization of gaseous aluminum fluoride products continually endows particles opposite momentum.

关键词： Aluminum nanoparticle Sintering Combustion Molecular dynamics simulation

One-step electrochemical fabrication of bilayered MgO/polymer coating on magnesium alloy

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Frontiers of Materials Science 2014年第3期8卷 307-312页

作者： jun LIANG Ren-Hui ZHANG Zhen-jun peng Bai-Xing liu State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

This research demonstrates a novel one-step electrochemical method to fabricate thick bilayer coatings on magnesium alloy in acid phosphate electrolyte containing aniline monomer and styrene-acrylic emulsion （SAE） with pulsed DC voltage, The morphologies, XRD and FTIR results show that the bilayer coating consists of an inner oxide layer and an outer polyaniline （PANI）/SAE composite layer, It is believed that the bilayered structure achieved results from a hybrid process combining electropoly-merization （EPM） of aniiine, electrophoretic deposition （EPD） of SAE and plasma electrolyte oxidation （PEO） of magnesium alloy substrate. Electrochemical corrosion tests indicate that the bilayer coating can provide superior corrosion protection to the magnesium alloy substrate in 3.5 wt.% NaCl solution.

关键词： magnesium alloy bilayer coating EPD PEO corrosion resistance

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World Journal of Gastroenterology 2019年第23期25卷 2898-2910页

作者： Wei-Dong Fan Tao Chen peng-jun liu Department of Gastroenterology the Affiliated Zhangjiagang Hospital of Soochow UniversityZhangjiagang 215600Jiangsu ProvinceChina Department of Gastroenterology the Wujin Hospital Affiliated to Jiangsu UniversityChangzhou 213002Jiangsu ProvinceChina

BACKGROUND NIMA related kinase 2(NEK2) is closely related to mitosis, and it is currently considered to be over-expressed frequently in many poorly prognostic ***, the effect of the up-regulated NEK2 on cellular signaling in tumors,such as gastric cancer(GC), is *** To determine the role of the up-regulation of NEK2 in *** To investigate the pathological significance of NEK2 in GC, the expression pattern of NEK2 in GC was investigated based on the 'Oncomain' database and compared between 30 pairs of cancer samples and adjacent tissues. The coexpression of NEK2 and ERK in GC was analyzed using The Cancer Genome Atlas(TCGA) database and confirmed in clinical samples by quantitative realtime PCR(qRT-PCR), and the survival curve was also plotted. Western blot or qRT-PCR was used to analyze the effect of NEK2 on the phosphorylation levels of ERK and c-jun in two GC cell lines(BGC823 and SGC7901) with NEK2 overexpression, and the expression of the downstream effector cyclin ***, CCK8, EdU incorporation assay, and flow cytometry were used to detect the proliferative ability of BGC823 and SGC7901 cells with stably silenced *** NEK2 was significantly up-regulated in human GC tissues. ERK was significantly associated with NEK2 expression in human clinical specimens, and combined overexpression of NEK2 and ERK potentially forecasted a poor prognosis andsurvival in GC patients. NEK2 knockdown in GC cells inhibited ERK and c-jun phosphory-lation and reduced the transcription of cyclin D1. More interestingly,NEK2 can rescue the inhibition of cellular viability, proliferation, and cell cycle progression due to ERK *** Our results indicate that NEK2 plays a carcinogenic role in the malignant proliferation of GC cells via the ERK/MAPK signaling, which may be important for treatment and improving patient survival.

关键词： NIMA related kinase 2 ERK/MAPK signaling Cyclin D1 Cell proliferation Gastric cancer

Hardware Implementation and Simulations of Joint Coding and Modulation Diversity MIMO-OFDM Scheme

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Journal of Harbin Institute of Technology(New Series) 2013年第3期20卷 27-34页

作者： Xiang Gao Zhan-Ji Wu Long-Fei Hua jun-peng liu School of Information and Communication Engineering Beijing University of Posts and Telecommunications

This paper presents an efficient Joint Coding and Modulation Diversity ( JCMD ) scheme. The proposed scheme applied modulation diversity technique to MIMO-OFDM system which can effectively use time, frequency and space diversity combined with channel coding. In fading channel,the proposed scheme not only achieves high spectral efficiency,but also greatly enhances the reliability of wireless transmission. The self- developed hardware prototype system proves that the proposed scheme can be realized and has high reliability. Compared with traditional MIMO-OFDM scheme based on bit-interleaved coded modulation ( BICM) ,software and hardware simulation results show that the proposed scheme with the optimal rotational angle can obtain a significant performance advantage both for precoded and non-precoded system in the condition of non-perfect channel knowledge and non-ideal synchronization.

关键词： multiple input multiple output ( MIMO) orthogonal frequency division multiplexing ( OFDM) modulation diversity channel estimation

Axial mechanical experiments of unbonded flexible pipes

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Petroleum Science 2020年第5期17卷 1400-1410页

作者： jun-peng liu Murilo Augusto Vaz Rong-Qi Chen Meng-Lan Duan Irving Hernandez College of Safety and Ocean Engineering China University of PetroleumBeijing 102249China Ocean Engineering Program Federal University of Rio de JaneiroRio de JaneiroBrazil Engineering and Construction Department China National Off shore Oil CorporationBeijing 100010China

Axial structural damping behavior induced by internal friction and viscoelastic properties of polymeric layers may have an inevitable influence on the global analysis of flexible *** order to characterize this phenomenon and axial mechanical responses,a full-scale axial tensile experiment on a complex flexible pipe is conducted at room temperature,in which oscillation forces at different frequencies are applied on the *** parameters to be identified are axial strains which are measured by three kinds of instrumentations:linear variable differential transformer,strain gauge and camera united particle-tracking *** corresponding plots of axial force versus axial elongation exhibit obvious nonlinear hysteretic ***,the loss factor related to the axial structural damping behavior is found,which increases as the oscillation loading frequency *** axial strains from the three measurement systems in the mechanical experiment indicate good agreement,as well as the values of the equivalent axial *** damping generated by polymeric layers is relatively smaller than that caused by friction ***,it can be concluded that friction forces maybe dominate the axial structural damping,especially on the conditions of high frequency.

关键词： Flexible pipes Hysteresis behavior Structural damping Mechanical experiment

Preparation of CaS:Eu^(2+) Phosphor by Microwave Heating Method and its Luminescence

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Chinese Chemical Letters 2000年第9期11卷 843-846页

作者： peng jun liu Ying Liang liu Department of Chemistry, Jinan University, Guangzhou 510632 Department of Chemistry, Hainan Normal College, Haikou 571158 Jinan Univ Dept Chem Guangzhou 510632 Peoples R China Hainan Normal Coll Dept Chem Haikou 571158 Peoples R China

This is the first report of using the microwave heating technique to synthesize calcium sulphide activated by europium whose structure is determined as the face-centered cubic by conventional X-ray powder diffraction method. The phosphor has maximum excitation peaks located at 280 urn and 560 urn and the maximum emission of the phosphor is 630 nm. When the concentration of Eu^(2+) in CaS increases from I .0 × 10^(-5) to l.0 × 10^(-2) mole per mole host, the body colour of the calcium sulphide activated with europium changes from white, through light-red to pink to deep-red. The phosphor obtains the longest afterglow at the concentration of 0.1% Eu^(2+)doped and is a kind of good material excited by sunlight.

关键词： Microwave radiation heating calcium sulphide europium luminescence.

Synthesis and Antibacterial Activities of Selenide Derivatives of Benzisoselenazolone

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Wuhan University Journal of Natural Sciences 2001年第4期6卷 851-853页

作者： Yang Li ping, Wu jun, peng Yun shan, liu Xiu fang, Xu Han sheng College of Chemistry and Molecular, Wuhan University, Wuhan 430072, China Wuhan University College of Chemistry and Molecular Wuhan China (GRID:grid.49470.3e) (ISNI:***)

A series of Benzisolselenazolone (BISA) derivatives were synthesized and evaluated for their antibacterial activities againstE coli. by using LKB-2277 bioactivity monitor. Other bioactivities were tested by the method of High Throughput Screening for pharmaceutical activity compounds (HTP) BISA derivatives 3b, at the concentration of 40 μg/mL, showed 100%antibacterial activity and 62%inhibition rate of aldose reductase (at the concentration of 5μg/mL). These new compound structures have determined by IR,1H NMR and MS spectra.

关键词： BISA Ebselen antibacterial activity NO synthase Aldose reductase

Matrix metalloproteinase 9 level as an indicator for restenosis following cervical and intracranial angioplasty and stenting

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Neural Regeneration Research 2015年第4期10卷 631-635页

作者： jun-peng liu Yin-zhou Wang Yong-kun Li Qiong Cheng Zheng Zheng Department of Neurology Fujian Provincial HospitalProvincial Clinical Department of Fujian Medical University

Cervical and intracranial angioplasty and stenting is an effective and safe method of reducing the risk of ischemic stroke, but it may be affected by in-stent restenosis. The present study in-vestigated serum level of matrix metalloproteinase 9 as a predictor of restenosis after 40 patients underwent cervical and/or intracranial angioplasty and stenting. Results showed that resteno-sis occurred in 30% （3/10） of patients when the serum level of matrix metalloproteinase 9 at 3 days after surgery was 2.5 times higher than preoperative level. No restenosis occurred when the serum level of matrix metalloproteinase 9 at 3 days after surgery was not 2.5 times higher than preoperative level. Restenosis occurred in 12% （2/17） of patients when the serum level of matrix metalloproteinase 9 was higher than preoperative level for more than 30 days after surgery, but only occurred in 4% （1/23） of patients when the serum level of matrix metalloproteinase 9 was higher than preoperative level for less than 30 days after surgery. However, the differences observed were not statistically signiifcant （P 〉 0.05）. Experimental ifndings indicate that when the serum level of matrix metalloproteinase 9 is 2.5 times higher than preoperative level at 3 days after cervi-cal and intracranial angioplasty and stenting, it may serve as a predictor of in-stent restenosis.

关键词： nerve regeneration matrix metalloproteinase 9 cervical and intracranial angioplasty and stenting restenosis intracranial artery stenosis neural regeneration

Probabilistic Methods in Multi-Class Brain-Computer Interface

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Journal of Electronic Science and Technology of China 2009年第1期7卷 12-16页

作者： Ping Yang Xu Lei Tie-jun liu peng Xu De-Zhong Yao The authors are with the Key Laboratory for NeuroInfonnation of Ministry of Education School of Life Science and Technology University of Electronic Science and Technology of China Chengdu 610054 China

Abstract-Two probabilistic methods are extended to research multi-class motor imagery of brain-computer interface （BCI）： support vector machine （SVM） with posteriori probability （PSVM） and Bayesian linear discriminant analysis with probabilistic output （PBLDA）. A comparative evaluation of these two methods is conducted. The results shows that： 1） probabilistie information can improve the performance of BCI for subjects with high kappa coefficient, and 2） PSVM usually results in a stable kappa coefficient whereas PBLDA is more efficient in estimating the model parameters.

关键词： Bayesian linear discriminant analysis brain-computer interface kappa coefficient support vector machine.

Preliminary Design of a System for Picking up Audio-Signals From Bubble Detectors GAO Si-ze1,NI Bang-fa,ZHANG Gui-ying,XIAO Cai-jin,liu Cun-xiong, CHEN Zhe1,NIE peng,liu Chao1,ZHAO Chang-jun (*** of Physics Science and Engineering Technology,Guang

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Preliminary Design of a System for Picking up Audio-Signals ...