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Chinese Chemical Letters 2022年第5期33卷 2692-2696页

作者： Zhaoqing Cai Huijun zou yirui Chen Zheng Wang Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

We herein proposed a sample introduction technique based on solution cathode glow discharge(SCGD)of a portable design for inductively coupled plasma-optical emission spectrometry(ICP-OES)and its ap-plication in sensitive determination of *** products from SCGD containing mercury vapor,were transported by an Ar flow to ICP spectrometer for detection.A gas liquid separator(GLS)and a dryer were used to condense and remove most of the accompanying moisture,which greatly improved both the stability and sensitivity of the *** detection limit(DL)acquired by this developed method was 0.22μg/L(194.1 nm),which was nearly 82 times lower than that obtained by pneumatic nebuliza-tion(PN).The relative standard deviation(RSD)was 1.4%(n=14)for a 50μg/L *** solution(HNO_(3),pH 1)can effectively elute mercury *** accuracy and practicality were also demonstrated by the determination of GBW10029(fish)certified reference material,shrimp,crawfish,soil and human hair *** results showed good consistency with the certified values and the values obtained us-ing inductively coupled plasma−mass spectrometry.

关键词： Solution cathode glow discharge Vapor generation ICP-OES Mercury Microplasma

Hierarchical Control of Ride Height System for Electronically Controlled Air Suspension Based on Variable Structure and Fuzzy Control Theory

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Chinese Journal of Mechanical Engineering 2015年第5期28卷 945-953页

作者： XU Xing ZHOU Kongkang zou Nannan JIANG Hong CUI Xiaoli School of Automotive and Traffic Engineering Jiangsu University School of Mechanical Engineering Jiangsu University School of Mechanical Engineering Hunan Institute of Technology

The current research of air suspension mainly focuses on the characteristics and design of the air spring. In fact, electronically controlled air suspension （ECAS） has excellent performance in flexible height adjustment during different driving conditions. However, the nonlinearity of the ride height adjusting system and the uneven distribution of payload affect the control accuracy of ride height and the body attitude. Firstly, the three-point measurement system of three height sensors is used to establish the mathematical model of the ride height adjusting system. The decentralized control of ride height and the centralized control of body attitude are presented to design the ride height control system for ECAS. The exact feedback linearization method is adopted for the nonlinear mathematical model of the ride height system. Secondly, according to the hierarchical control theory, the variable structure control （VSC） technique is used to design a controller that is able to adjust the ride height for the quarter-vehicle anywhere, and each quarter-vehicle height control system is independent. Meanwhile, the three-point height signals obtained by three height sensors are tracked to calculate the body pitch and roll attitude over time, and then by calculating the deviation of pitch and roll and its rates, the height control correction is reassigned based on the fuzzy algorithm. Finally, to verify the effectiveness and performance of the proposed combined control strategy, a validating test of ride height control system with and without road disturbance is carried out. Testing results show that the height adjusting time of both lifting and lowering is over 5 s, and the pitch angle and the roll angle of body attitude are less than 0.15°. This research proposes a hierarchical control method that can guarantee the attitude stability, as well as satisfy the ride height tracking system.

关键词： electronically controlled air suspension (ECAS) ride height body attitude hierarchical control

Halogenated benzothiadiazole-based conjugated polymers as efficient photocatalysts for dye degradation and oxidative coupling of benzylamines

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Chinese Chemical Letters 2022年第5期33卷 2736-2740页

作者： Chu Chu Yuancheng Qin Cailing Ni Jianping zou Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle Nanchang Hangkong UniversityNanchang 330063China

Donor-acceptor(D-A)conjugated polymers are widely used in photovoltaic applications and heteroge-neous catalysis due to their tunable building block and pre-designable ***,a series of ad-justable Donor-acceptor(D-A)benzothiodiazole-based conjugated polymers were designed and *** photocatalytic performance could be improved by fine-tuning the chemical structure by halo-gen substitution(F or Cl).The polymers exhibited excellent optoelectronic properties and were effective photocatalysts for the degradation of RhB and MO dyes,as well as promoting the oxidative coupling of *** degradation of RhB and MO occurred in 30 min under visible light radiation,while the yield of benzylamine coupling mediated by superoxide anion was as high as 82%.Systematic characterization methods were used to gain insights on the unique photocatalytic performance of the *** findings provide further insights into the design and synthesis of benzothiadiazole-based conjugated polymers as promising organic photocatalysts for solar energy conversion.

关键词： Conjugated polymer Band gap Dye degradation Photocatalysis Benzylamine oxidation

SYNTHESIS, PROPERTIES AND ELECTROPOLYMERIZATION OF STAR-SHAPED OLIGOTHIOPHENES WITH HEXAKIS(FLUOREN-2-YL)BENZENE AS CORE

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Chinese Journal of Polymer Science 2013年第6期31卷 938-945页

作者： Yang zou Yuan Liu Jin-gui Qin 杨楚罗 Department of Chemistry Hubei Key Lab on Organic and Polymeric Opto-Electronic Materials Wuhan University

Star-shaped oligothiophenes with hexakis（fluoren-2-yl）benzene （HFB） as cores were designed and synthesized. Grafting thiophene units to HFB results in a bond flattening of the core, and makes the molecules a flipping-twist shape. Their thermal, photophysical and electrochemical properties were studied. Highly cross-linked conjugated polymers can be produced by electropolymerization of T1-T3.

关键词： Star-shaped molecules Hexakis(fluoren-2-yl)benzene Oligothiophene Electropolymerization.

Wet spinning of PVA composite fibers with a large fraction of multi-walled carbon nanotubes

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Progress in Natural Science:Materials International 2015年第5期25卷 445-452页

作者： Dengpan Lai yizhe Wei Liming zou Yongjing Xu Hongwei Lu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and Engineering Donghua University

PVA composites fibers with a large fraction of multi-walled carbon nanotubes modified by both covalent and non-covalent functionalization were produced by a wet-spinning *** XQ-1 tensile tester,thermogravimetric analysis,scanning electron microscopy,differential scanning calorimetry,and wide-angle X-ray diffraction were used to characterize the properties of PVA/MWNT composite *** TGA results suggested that MWNTs content in composite fibers were ranged from 5.3 wt%to 27.6 wt%.The mechanical properties of PVA/MWNT composite fibers were obviously superior to pure PVA *** Young's modulus of composite fibers enhanced with increasing the content of MWNTs,and it rised gradually from 6.7 GPa for the pure PVA fiber to 12.8 GPa for the composite fibers with 27.6 wt%***,the tensile strength increased gradually from 0.39 GPa for the pure PVA fiber to 0.74 GPa for the composite fibers with 14.4 wt%***,the tensile strength of the composite fibers decreased as the MWNTs content up to 27.6 wt%.SEM results indicated that the MWNTs homogeneously dispersed in the composite fibers,however some agglomerates also existed when the content of MWNTs reached27.6 wt%.DSC results proved strong interfacial interaction between MWNTs and PVA chain,which benefited composite fibers in the efficient *** characterization showed that the orientation of PVA molecules declined from 94.1%to 90.9%with the increasing of MWNTs *** good dispersibility of MWNTs throughout PVA matrix and efficient stress-transfer between MWNTs and PVA matrix may contributed to significant enhancement in the mechanical properties.

关键词： Multi-walled carbon nanotubes(MWNTs) Poly(vinyl alcohol)(PVA) Wet-spinning Composite fibers

Linear Canonical Transform Related Operators and Their Applications to Signal Analysis——Part I: Fundamentals

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Chinese Journal of Electronics 2015年第2期24卷 102-109页

作者： WANG Xiaobo ZHANG Qiliang ZHOU You QIAN Jing zou Hongxing Department of Automation Tsinghua University Air Force Engineering University

In recent years, the Linear canonical transform(LCT) has been recognized as a powerful tool in signal processing scenarios and optics. In this two-part paper, the issue of unitary and Hermitian operators and their duality concept associated with LCT are addressed. In Part I,based on the proposed operators, three LCT-related topics are derived. Firstly, the definitions of convolution and correlation operations in LCT domain are constructed. Secondly, a new transform which is named as Linear canonical mellin transform(LCMT) is introduced and then convolution and correlation operations in LCMT domain are ***, the so-called joint canonical distributions which satisfy the canonical transform marginal are given. Part II concerns two applications of the theory derived in Part I for signal analysis.

关键词： Linear canonical transform Unitary and Hermitian operators Convolution and correlation operations Generalized marginals.

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Synthesis and Characterization of Magnetic MAX Phase(Cr2-xMnx)GaC

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Journal of Wuhan University of Technology(Materials Science) 2020年第2期35卷 363-367页

作者： YAN Ming LI Chao zou Yunqi YANG Mengliu Hubei Provincial Key Laboratory of Green Materials for Light Industry Hubei University of TechnologyWuhan 430068China Collaborative Innovation Center of Green Light-weight Materials and Processing Hubei University of TechnologyWuhan 430068China College of Materials and Chemical Engineering Hubei University of TechnologyWuhan 430068China

The solid solution of (Cr2-xMnx)GaC with magnetic properties was synthesized by pressureless *** composition,morphology,and magnetic properties of products were characterized by X-ray diffraction (XRD),scanning electron microscopy (SEM),transmission electron microscopy (TEM),and vibrating sample magnetometer (VSM).The experimental results indicate that the solid solubility of Mn is related to the value of x,which reaches the maximum at x=0.4 and the characteristic peaks shift effect is most *** the solution treatments,the samples of (Cr2-xMnx)GaC still presents the layered structure of MAX phase,and the lattice parameter has decreased *** characterizing the magnetic properties of (Cr2-xMnx)GaC,the successful doping of Mn atoms was confirmed,and the intensity of magnetism was positively correlated with the doping amounts of Mn.

关键词： MAX phase Cr2GaC sintering solid solution magnetic

High-level representation sketch for video event retrieval

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Science China(Information Sciences) 2016年第7期59卷 158-172页

作者： Yu ZHANG Xiaowu CHEN Liang LIN Changqun XIA Dongqing zou State Key Laboratory of Virtual Reality Technology and Systems School of Compute Science and EngineeringBeihang University School of Advanced Computing Sun Yat-Sen University

Representing video events is an essential step for a wide range of visual applications. In this paper,we propose the event sketch, a high-level event representation, to depict the dynamic properties of video events composed of actions of semantic objects. We show that this representation can facilitate a novel sketch based video retrieval(SBVR) system, which has not been considered before to the best of our knowledge. In this system, users are allowed to draw the evolutions(e.g. spatiotemporal layouts and behaviors of semantic objects)on a board, and retrieve the events whose semantic objects have the similar evolutions from a database. To do this, event sketches are constructed on both the user queries and database videos, and compared under a novel graph-matching scheme based on data-driven Monta Carlo Markov chain(DDMCMC). To test our approach, we collect a novel dataset of goal events in real soccer videos, which consists actions of multiple players and shows large variability in the evolution process of the events. Experiments on this dataset and the publicly available dataset CAVIAR demonstrated the effectiveness of the proposed approach.

关键词： video retrieval event representation event sketch drawing board distance function relevance feedback DDMCMC

Shakedown Criterion Employing Actual Residual Stress Field and Its Application in Numerical Shakedown Analysis

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Chinese Journal of Mechanical Engineering 2015年第5期28卷 919-927页

作者： zou Zongyuan GUO Baofeng LI yinxiao JIN Miao ZHAO Shiyan Key Laboratory of Advanced Forging & Stamping Technology and Science of Ministry of Education Yanshan University Chinese 91315 People's Liberation Army Troops

Construction of the static admissible residual stress field and searching the optimal field are key tasks in the shakedown analysis methods applying the static theorem. These methods always meet dimension obstacles when dealing with complex problems. In this paper, a novel shakedown criterion is proposed employing actual residual stress field based on the static shakedown theorem. The actual residual stress field used here is produced under a specified load path, which is a sequence of proportional loading and unloading from zero to all the vertices of the given load domain. This ensures that the shakedown behavior in the whole load domain can be determined based on the theorem proposed by K6nig. The shakedown criterion is then implemented in numerical shakedown analysis, The actual residual stress fields are calculated by incremental finite element elastic-plastic analysis technique for finite deformation under the specified load path with different load levels. The shakedown behavior and the shakedown limit load are determined according to the proposed criterion. The validation of the criterion is performed by a benchmark shakedown example, which is a square plate with a central hole under biaxial loading. The results are consistent with existing results in the literatures and are validated by full cyclic elastic-plastic finite element analysis. The numerical shakedown analysis applying the proposed criterion avoids processing dimension obstacles and performing full cyclic elastic-plastic analysis under arbitrary load paths which should be accounted for appearing. The effect of material model and geometric changes on shakedown behavior can he considered conveniently.

关键词： elastoplastic finite element shakedown criterion specified load path actual residual stress field

A general cocatalyst strategy for performance enhancement in nickel catalyzed ethylene(co)polymerization

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Chinese Chemical Letters 2022年第9期33卷 4363-4366页

作者： Quan Wang Zhao Zhang Chen zou Changle Chen CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China

The tuning of olefin-polymerization catalyst properties through ligand modifications is efficient but requires complicated and costly *** this contribution,a simple Bu_(2)Mg-based cocatalyst strategy is designed that can simultaneously enhance the catalytic properties(activity,thermal stability,polymer molecular weight,branching density,melting point,etc.)of various nickel catalysts(α-diimine nickel,pyridine imine nickel and iminopyridine-N-oxide nickel)in ethylene polymerization,and enable great product morphology *** example,a simpleα-diimine nickel catalyst can demonstrate polymerization activity of up to 1.29×10^(7)g mol^(−1)h^(−1)and molecular weight of up to 1.90×10^(6)g/mol in the presence of Bu_(2)Mg *** resulting polyethylenes exhibit excellent mechanical properties,with tensile stress of up to 47.4 MPa and strain of up to 1020%.This cocatalyst strategy is generally applicable to different nickel catalysts,and can lead to property enhancement in ethylene copolymerization with a series of polar comonomers such as methyl 10-undecylenate,10-undecylenic acid and 10-undecenol.

关键词： Nickel Cocatalyst Magnesium Ethylene polymerization