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Chinese Journal of Chemistry 2022年第1期40卷 39-45页

作者： Wei Zeng Mao-Hua lin ling-Yun Zhu mei-Jin lin Key Laboratory of Molecule Synthesis and Function Discovery College of ChemistryFuzhou UniversityFuzhouFujian 350116China College of Materials Science and Engineering Fuzhou UniversityFuzhouFujian 350116China

Developme nt of subcellular orga nelle-targeted bioimagi ng probes is of great imports nee in the field of early detection of diseases and exploring the behaviors of subcellular ***,we present a triphenyIphosphonium functionalized conjugated macrocyclic tetramaleimide(TPP-CMT)as a mitochondrial-targeting bioimaging *** core of TPP-CMT is obtained by connecting two pyrenes and two benzenes through four *** unique structure endows TPP-CMT with exceptional far red/near-i nfirared aggregati on-induced emissi on(FR/NIR-AIE)***-CMT is an excelle nt fluoresce nt emitter in most solve nts and eve n in solid *** qua ntum yield of TPP-CMT was higher tha n 27% when dissolved in comm on middle-polarity orga nic solve nt and this value remained at 28.2% in its solid *** in troducti on of four triphe ny Iphosph onium on maleimide positions endows TPP-CMT with mitochondrial-targeting *** to the FR/NIR-AIE characteristics and the mitochondri-al-targeti ng ability,this well-desig ned fluoresce nt probe was successfully employed for mitochondrial targeti ng bioimaging of HeLa and HepG2 cells.

关键词： Fluorescent probes Macrocycles Photophysics FR/NIR-AIE Mitochondrial-targeting bioimaging

Biological control experiment of excess propagation of Cyclops for drinking water security

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Journal of Environmental Sciences 2007年第3期19卷 290-294页

作者： lin Yao CUI Fu-yi LIU Dong-mei College of Environmental Science and Engineering Hohai University Nanjing 210098 China School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China

Cyclops of zooplankton propagated excessively in eutrophic water body and could not be effectively inactivated by the conventional disinfections process like chlorination due to its stronger resistance to oxidation. In this study, an ecological project was put forward for the excess propagation control of Cyclops by stocking the filter-feeding fishes such as silver carp and bighead carp under the condition of no extraneous nutrient feeding. The results of experiments with different stocking biomass showed that the propagation of Cyclops could be controlled effectively, and the water quality was improved simultaneously by impacting on nutriment level and plankton community structure at proper stocking density of 30 g/m^3 of water. The growth of Cyclops may not be effectually controlled with lower biomass of fish （10 g）, and the natural food chain relation may be destroyed for Cyclops dying out in water while the intense stocking of 120 g per cubic meter of water. In addition, the high predator pressure may accelerate supplemental rate of nutrients from bottom sediments to water body to add the content of total nitrogen and phosphorus in water.

关键词： filter-feeding fishes Cyclops zooplankton biomanipulation water treatment

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球形花状多孔碳材料制备及应用

化学试剂 2025年第1期47卷 39-44页

作者：刘亚东白广梅邱文革北京工业大学材料科学与工程学院北京100124

采用老化处理与水热碳化结合的策略,以葡萄糖为碳源,成功制备了球形花状多孔碳材料,相应Pd(OH)_(2)/C催化剂在笼形底物的氢解脱苄反应中显示出优异的催化活性。具体研究了MgCl_(2)/Na_(2)CO_(3)物质的量比、葡萄糖浓度和老化处理对碳材... 详细信息

采用老化处理与水热碳化结合的策略,以葡萄糖为碳源,成功制备了球形花状多孔碳材料,相应Pd(OH)_(2)/C催化剂在笼形底物的氢解脱苄反应中显示出优异的催化活性。具体研究了MgCl_(2)/Na_(2)CO_(3)物质的量比、葡萄糖浓度和老化处理对碳材料形貌的影响,确定了球形花状多孔碳材料的较佳制备条件。通过扫描电镜、粉末X射线衍射和氮气吸/脱附测试表征了原位自生模板剂和多孔碳材料的形貌、晶相结构及比表面积和孔径分布。发现将MgCl_(2)和Na_(2)CO_(3)在常温下混合,首先生成的是棒状碳酸镁,经过80℃老化处理后,转变为球形花状碱式碳酸镁,它是葡萄糖水热碳化的模板剂。

关键词：多孔碳材料水热合成原位自生模板法老化处理氢解脱苄

Webpage Matching Based on Visual Similarity

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Computers, Materials & Continua 2022年第5期71卷 3393-3405页

作者： Mengmeng ge Xiangzhan Yu lin Ye Jiantao Shi School of Cyberspace Science Harbin Institute of TechnologyHarbin150001China Department of Computer and Information Science Temple UniversityPhiladelphia42101USA

With the rapid development of the Internet,the types of webpages are more abundant than in previous ***,it becomes severe that people are facing more and more significant network security risks and enormous losses caused by phishing webpages,which imitate the interface of real webpages and deceive the *** better identify and distinguish phishing webpages,a visual feature extraction method and a visual similarity algorithm are ***,the visual feature extraction method improves the Visionbased Page Segmentation(VIPS)algorithm to extract the visual block and calculate its signature by perceptual hash ***,the visual similarity algorithm presents a one-to-one correspondence based on the visual blocks’coordinates and *** the weights are assigned according to the tree structure,and the similarity of the visual blocks is calculated on the basis of the measurement of the visual features’Hamming ***,the visual similarity of webpages is generated by integrating the similarity and weight of different visual ***,multiple pairs of phishing webpages and legitimate webpages are evaluated to verify the feasibility of the *** experimental results achieve excellent performance and demonstrate that our method can achieve 94%accuracy.

关键词： Web security visual feature perceptual hash visual similarity

Stability analysis of unsaturated soil slope during rainfall infiltration using coupled liquid-gas-solid three-phase model

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Water Science and Engineering 2016年第3期9卷 183-194页

作者： Dong-mei Sun Xiao-min Li Ping Feng Yong-ge Zang State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University

generally, most soil slope failures are induced by rainfall infiltration, a process that involves interactions between the liquid phase, gas phase,and solid skeleton in an unsaturated soil slope. In this study, a loosely coupled liquid-gas-solid three-phase model, linking two numerical codes,TOUGH2/EOS3, which is used for water-air two-phase flow analysis, and FLAC^(3D), which is used for mechanical analysis, was established. The model was validated through a documented water drainage experiment over a sandy column and a comparison of the results with measured data and simulated results from other researchers. The proposed model was used to investigate the features of water-air two-phase flow and stress fields in an unsaturated soil slope during rainfall infiltration. The slope stability analysis was then performed based on the simulated water-air two-phase seepage and stress fields on a given slip surface. The results show that the safety factor for the given slip surface decreases first, then increases, and later decreases until the rainfall stops. Subsequently, a sudden rise occurs. After that, the safety factor decreases continually and reaches its lowest value, and then increases slowly to a steady value. The lowest value does not occur when the rainfall stops, indicating a delayed effect of the safety factor. The variations of the safety factor for the given slip surface are therefore caused by a combination of pore-air pressure, matric suction, normal stress, and net normal stress.

关键词： Coupled liquid-gas-solid three-phase model Pore-air pressure Unsaturated soil slope stability Rainfall infiltration

A new neuroprotective bakkenolide from the rhizome of Petasites tricholobus

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Chinese Chemical Letters 2008年第7期19卷 841-844页

作者： Na Zhang mei Li Guo ge Zhang Run Ping Li Department of Pharmacognosy School of Pharmacy Second Military Medical University Shanghai 200433 China Department of Diving Medicine Faculty of Naval Medicine Second Military Medical University Shanghai 200433 China

A new bakkenolide-type compound, bakkenolide-Va（1）, was isolated from the rhizome of Petasites tricholobus. The structure was characterized on the basis of various NMR （1H, 13C, 1H-1H COSY, HMQC, HMBC and NOESY） and mass spectrometry data. The neuroprotective activity of bakkenolide-Va was investigated in primarily cultured neurons treated by hypoxia-ghicose deprivation and various types of oxidative insults.

关键词： Petasites tricholobus Compositae Bakkenofide-Va Neuroprotection

Effect of transition metal oxides doping on Ce_(0.9)Sm_(0.05)Nd_(0.05)O_(1.95) solid electrolyte materials

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Journal of Advanced Ceramics 2012年第2期1卷 150-156页

作者： Ming ZHOU lin ge Han CHEN Lucun GUO College of Materials Science and Engineering Nanjing University of TechnologyNo.5 Xinmofan RoadNanjing210009China

The effect of transition metal oxides(TMOs)Co_(O1.5),Fe_(O1.5)and MnO_(2)addition on Ce_(0.9)Sm_(0.05)Nd_(0.05)O_(1.95)was *** crystal structures,microstructures,thermal expansion and electrical properties were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),dilatometer and AC impedance spectroscopy,*** results show that the TMOs addition remarkably promotes the densification of Ce_(0.9)Sm_(0.05)Nd_(0.05)O_(1.95)and reduces the sintering temperature by~150℃.The samples with TMOs addition sintered at 1450℃exhibit higher conductivities than those sintered at 1500℃.The maximum conductivity of 0.040 ***^(-1)at 700℃was achieved with 1 mol%FeO1.5 doping when sintered at 1450℃.In addition,the thermal expansion was linear for all the *** doping of TMOs does not appreciably change thermal expansion coefficient.

关键词： transition metal oxides microstructure thermal expansion ionic conductivity

Robust exponential stability analysis of a larger class of discrete-time recurrent neural networks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第12期8卷 1912-1920页

作者： ZHANG Jian-hai ZHANG Sen-lin LIU mei-qin Department of System Science ＆ Engineering School of Electrical Engineering Zhejiang University Hangzhou 310027 China

The robust exponential stability of a larger class of discrete-time recurrent neural networks (RNNs) is explored in this paper. A novel neural network model, named standard neural network model (SNNM), is introduced to provide a general framework for stability analysis of RNNs. Most of the existing RNNs can be transformed into SNNMs to be analyzed in a unified way. Applying Lyapunov stability theory method and S-Procedure technique, two useful criteria of robust exponential stability for the discrete-time SNNMs are derived. The conditions presented are formulated as linear matrix inequalities (LMIs) to be easily solved using existing efficient convex optimization techniques. An example is presented to demonstrate the transformation procedure and the effectiveness of the results.

关键词： Standard neural network model (SNNM) Robust exponential stability Recurrent neural networks (RNNs) Discrete-time Time-delay system linear matrix inequality (LMI)

Energy-efficient localization and target tracking via underwater mobile sensor networks

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Frontiers of Information Technology & Electronic Engineering 2018年第8期19卷 999-1012页

作者： Hua-yan CHEN mei-qin LIU Sen-lin ZHANG State Key Laboratory of Industrial Control Technology Zhejiang University College of Electrical Engineering Zhejiang University

Underwater mobile sensor networks(UMSNs) with free-floating sensors are more suitable for understanding the immense underwater environment. Target tracking, whose performance depends on sensor localization accuracy, is one of the broad applications of UMSNs. However, in UMSNs, sensors move with environmental forces,so their positions change continuously, which poses a challenge on the accuracy of sensor localization and target tracking. We propose a high-accuracy localization with mobility prediction(HLMP) algorithm to acquire relatively accurate sensor location estimates. The HLMP algorithm exploits sensor mobility characteristics and the multistep Levinson-Durbin algorithm to predict future positions. Furthermore, we present a simultaneous localization and target tracking(SLAT) algorithm to update sensor locations based on measurements during the process of target tracking. Simulation results demonstrate that the HLMP algorithm can improve localization accuracy significantly with low energy consumption and that the SLAT algorithm can further decrease the sensor localization error. In addition, results prove that a better localization accuracy will synchronously improve the target tracking performance.

关键词： Underwater mobile sensor networks Energy-efficient Sensor localization Target tracking

H_∞ reference tracking control design for a class of nonlinear systems with time-varying delays

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Frontiers of Information Technology & Electronic Engineering 2015年第9期16卷 759-768页

作者： mei-qin LIU Hai-yang CHEN Sen-lin ZHANG State Key Laboratory of Industrial Control Technology Zhejiang University College of Electrical Engineering Zhejiang University

This paper investigates the H∞ trajectory tracking control for a class of nonlinear systems with time- varying delays by virtue of Lyapunov-Krasovskii stability theory and the linear matrix inequality （LMI） technique. A unified model consisting of a linear delayed dynamic system and a bounded static nonlinear operator is introduced, which covers most of the nonlinear systems with bounded nonlinear terms, such as the one-link robotic manipulator, chaotic systems, complex networks, the continuous stirred tank reactor （CSTR）, and the standard genetic regulatory network （SCRN）. First, the definition of the tracking control is given. Second, the H∞ performance analysis of the closed-loop system including this unified model, reference model, and state feedback controller is presented. Then criteria on the tracking controller design are derived in terms of LMIs such that the output of the closed-loop system tracks the given reference signal in the H∞ sense. The reference model adopted here is modified to be more flexible. A scaling factor is introduced to deal with the disturbance such that the control precision is improved. Finally, a CSTR system is provided to demonstrate the effectiveness of the established control laws.

关键词： H∞ reference tracking Nonlinear system State feedback control Time-varying delays Unified model