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Control of stochastic spike motion in an excitable system via recycled noise

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Science China Chemistry 2011年第9期54卷 1504-1509页

作者： MA juan gao QingYu College of Chemical Engineering China University of Mining and Technology Xuzhou 221008 China

The control effect of recycled noise,generated by the superposition of a primary Gaussian noise source and a secondary source with a constant delay,has been studied in an excitable FitzHugh-Nagumo *** mainly focus on the performance of noise-induced spike and coherence resonance in a parameter region sub-threshold to supercritical Hopf *** fixed noise intensity,simulations show that the coherence(quantitatively measured by R,which is defined as the mean value of the spike interval time T normalized to its mean square root) and the emission velocity of the noise-induced spikes exhibit damped oscillations with the variation of delay time,demonstrating a new kind of multi-resonance ***,the optimal delay times for resonance and the fast emission velocity are related to the inherent frequency of the *** seems that there are some synchronization effects between the dynamic character of the system and the delay time of recycled *** results give clear information about how one can control the coherence and emission velocity of the noise-induced spike in a rather effective way,by deliberately adjusting the delay time and the fraction of the secondary noise.

关键词： stochastic spike excitable recycled noise coherent resonance

Three New Cucurbitacins from Hemsleya lijiangensis

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Chinese Chemical Letters 2003年第4期14卷 389-392页

作者： Ming Hua CHIU juan gao State Key Laboratory of Phytochemistry and Plant Resource in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650204

Three new cucurbitacins were isolated from the BuOH extract of the rhizomes of Hemsleya lijiangensis. Their structures were elucidated as 23, 24 -dihydro cucurbitacin F-16, 25-diacetate(1), 23, 24-dihydro cucurbitacin F-16, 25-diacetate-2-O-β-D glucopyranoside (2), 23, 24-dihydro-cucurbitacin F-16-acetate(3), respectively; by spectral analyses.

关键词： Hemsleya lijiangensis Cucurbitaceae Hemslecins D, E, F.

Fuzzy PID Control of Space Manipulator for Both Ground Alignment and Space Applications

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International Journal of Automation and computing 2014年第4期11卷 353-360页

作者： Fu-Cai Liu Li-Huan Liang juan-juan gao Key Lab of Industrial Computer Control of Hebei Province Yanshan University

Considering gravity change from ground alignment to space applications, a fuzzy proportional-integral-differential(PID)control strategy is proposed to make the space manipulator track the desired trajectories in different gravity environments. The fuzzy PID controller is developed by combining the fuzzy approach with the PID control method, and the parameters of the PID controller can be adjusted on line based on the ability of the fuzzy controller. Simulations using the dynamic model of the space manipulator have shown the effectiveness of the algorithm in the trajectory tracking problem. Compared with the results of conventional PID control,the control performance of the fuzzy PID is more effective for manipulator trajectory control.

关键词： Space manipulator trajectory tracking ground alignment space applications fuzzy proportional-integral-differential (PID) gravity environment

Polymers with tertiary amine groups for drug delivery and bioimaging

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Science China Chemistry 2016年第8期59卷 991-1002页

作者： Yu-juan gao Zeng-Ying Qiao Hao Wang CAS Center for Excellence in Nanoscience CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety National Center for Nanoscience and Techr ology Beijing 100190 China

Over the past decade, biopolymers have gained great interests especially in biomedicine due to their physical properties and/or chemical structures changes in response to external stimuli in a certain time fiarne or at a specific location. Among them, poly（β-amino ester）s, methacrylate-based block copolymers and polypeptide with tertiary amine groups have been extensively studied and exhibit pH sensitive properties due to the protonation of tertiary amine groups. The pH values in normal organs, tissues, and subcellular compartments are always different from those in pathological tissues. These interesting properties allow their applications in a variety of fields ranging from diagnosis and therapeutics of diseases. Here, we review the recent progress of poly（β-amino ester）s, methacrylate-based block copolymers and polypeptide with tertiary amine groups and their applications in drug delivery and bioimaging.

关键词： biopolymers tertiary amine groups pH-responsive drug delivery bioimaging

Flexible Gradient Poly(ether-ester)from the Copolymerization of Epoxides and c-Caprolactone Mediated by a Hetero-bimetallic Complex

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Chinese Journal of Polymer Science 2021年第8期39卷 1013-1019,I0007页

作者： Wei-Min Ren Hong-juan gao Tian-Jun Yue State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116024China

Copolymerization is a commonly employed method for optimizing the properties of polymer *** ether segments into polyesters main chain to obtain polyether-polyester copolymers is an effective strategy to realize the integration of multiple properties of polyester and polyether,and to develop more high-performance,multi-purpose polymer ***,the synthesis of poly(ether-ester)s is accessible by employing the biphenyl-linked heterodinuclear salen Cr-AI complex in the presence of PPNCI for the copolymerization of epoxides and£-caprolactone(CL).Monitoring the copolymerization process reveals that catalyst 1 exhibited good performance for the copolymerization of epoxides and CL,affording copolymers with a gradient sequence *** dynamic thermomechanical analysis(DMA)study indicates the obtained poly(ether-ester)s possess enhanced flexibility compared with the block copolymers or blend of PPO and PCL homopolymers with the same *** study provides a theoretical basis for the preparation of high-performance polymer materials.

关键词： Lactone Epoxide Copolymerization Poly(ether-ester)copolymer Dynamic mechanical analysis

Static load test and load transfer mechanism study of squeezed branch and plate pile in collapsible loess foundation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第7期8卷 1110-1117页

作者： gao Xiao-juan WANG Jin-chang ZHU Xiang-rong College of Civil Engineering and Architecture Zhejiang University Hangzhou 310027 China Institute of Architecture Engineering Henan University of Science and Technology Luoyang 471003 China Ningbo Institute of Technology Zhejiang University Ningbo 315005 China

As a special geological phenomenon, the character of collapsible loess foundation is collapsible when penetrated by water. This character leads to the soil losing load bearing capacity largely and may lead to foundation failure. Pile is a popular foundation used in collapsible loess. The squeezed branch and plate pile is a new type of pile developed in recent years and has not be used in a project before. In this paper three squeezed branch and plate piles are tested in collapsible loess after immersion processing. The results may be used for reference in similar construction project, and to provide theoretical references for de- signing of the squeezed branch and plate piles in engineering practice.

关键词： Collapsible loess foundation Squeezed branch and plate pile Immersion processing Full-scale static load test

Research on Feature Extraction of Remnant Particles of Aerospace Relays

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Chinese Journal of Aeronautics 2007年第3期20卷 253-259页

作者： WANG Shu-juan gao Hong-liang ZHAI Guo-fu Department of Electrical Engineering Harbin Institute of Technology Harbin 150001 China

The existence of remnant particles, which significantly reduce the reliability of relays, is a serious problem for aerospace relays. The traditional method for detecting remnant particles-particle impact noise detection （PIND）-can be used merely to detect the existence of the particle; it is not able to provide any information about the particles＇ material. However, information on the material of the particles is very helpful for analyzing the causes of remnants. By analyzing the output acoustic signals from a PIND tester, this paper proposes three feature extraction methods： unit energy average pulse durative time, shape parameter of signal power spectral density （PSD）, and pulse linear predictive coding coefficient sequence. These methods allow identified remnants to be classified into four categories based on their material. Furthermore, we prove the validity of this new method by processing P1ND signals from actual tests.

关键词： feature extraction aerospace relays remnant particles particle impact noise detection

Effects of iron(hydr)oxides on the degradation of diethyl phthalate ester in heterogeneous(photo)-Fenton reactions

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Journal of Environmental Sciences 2019年第6期31卷 5-13页

作者： Wenjuan Shuai Cheng Gu Guodong Fang Dongmei Zhou juan gao Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil Science Chinese Academy of Science University of Chinese Academy of Sciences State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University

This work studied the structural effects of hematite(α-Fe2 O3), 2-line ferrihydrite(HFO) and goethite(α-FeOOH) on diethyl phthalate ester(DEP) degradation. The results showed that the degradation of DEP was faster under 365 nm light irradiation than in the dark in the presence of iron(hydr)oxides. The apparent kinetic rates of DEP degradation followed the order HFO > goethite ≈ hematite in the dark and HFO > hematite > goethite under 365 nm light irradiation. Two pathways governed H2 O2 decomposition efficiency on iron(hydr)oxide surfaces:(1) forming UOH on inherent surface hydroxyl groups(Fe-OH) and(2) producing O2 and H2 O on the surface oxygen vacancies. X-ray photoelectron spectroscopy(XPS) analyses indicated that HFO not only has high Fe-OH content but also has high Vo content, resulting in its low H2 O2 utilization efficiency(η). DEP was degraded through hydrogen abstraction and deesterification, and the major products were(OH)2-DEP, mono-ethyl phthalate(MEP), OH-MEP,and phthalate acid(PA). The study is important in understanding the transformation of phthalate esters in top surface soils and surface waters under ultraviolet light.

关键词： Diethyl phthalate ester Iron(hydr)oxide Hydroxyl radical Heterogeneous Fenton reactions

A Two-Lane Cellular Automata Model with Influence of Next-Nearest Neighbor Vehicle

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Communications in Theoretical Physics 2006年第4期45卷 657-662页

作者： KONG Xian-juan gao Zi-You LI Ke-Ping School of Traffic and Transportation Beijing Jiaotong University Beijing 100044 China

In this paper, we propose a new two-lane cellular automata model in which the influence of the next-nearest neighbor vehicle is considered, The attributes of the traffic system composed of fast-lane and slow-lane are investigated by the new traffic model. The simulation results show that the proposed two-lane traffic model can reproduce some traffic phenomena observed in real traffic, and that maximum flux and critical density are close to the field measurements. Moreover, the initial density distribution of the fast-lane and slow-lane has much influence on the traffic flow states. With the ratio between the densities of slow lane and fast lane increasing the lane changing frequency increases, but maximum flux decreases. Finally, the influence of the sensitivity coefficients is discussed.

关键词： cellular automata car-following model double look-ahead model