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On disturbance rejection proportional-integral-differential control with model-free adaptation

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Control Theory and Technology 2023年第1期21卷 34-45页

作者： zhuo-Yun Nie Gao-Ming Li Lai-cheng Yan Qing-Guo Wang Ji-Liang Luo School of Information Science and Engineering Huaqiao UniversityXiamen 100190FujianChina Institute of Artificial Intelligence and Future Networks Beijing Normal UniversityZhuhai 519087GuangdongChina Guangdong Key Lab of AI and Multi-Modal Data Processing BNU-HKBU United International CollegeZhuhai 519087GuangdongChina

In this paper,an adaptive disturbance-rejection proportional–integral–differential(PID)control method is proposed for a class of nonlinear ***,PID-type criterion is introduced in a model-free adaptive control(MFAC)framework,which gives an optimal control interpretation for PID ***,the design of adaptive disturbance rejection PID is proposed based on this new interpretation to realize controller gain *** to the ingenious integration of active disturbance rejection and adaptive mechanism,the proposed adaptive disturbance rejection PID control scheme exhibits better control performance than MFAC ***,the boundedness of controller gain,the convergence of tracking error and the bounded-input–bounded-output stability are proved for the proposed control ***,the effectiveness of the proposed method is verified by numerical simulation.

关键词： Disturbance rejection PID Data-driven control-Error-driven model Model-free adaptive control

Inhibition of bromate formation by reduced graphene oxide supported cerium dioxide during ozonation of bromidecontaining water

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Frontiers of Environmental Science & Engineering 2019年第6期13卷 81-89页

作者： Bei Ye zhuo Chen Xinzheng Li Jianan Liu Qianyuan Wu cheng Yang Hongying Hu Ronghe Wang Shenzhen Environmental Science and New Energy Technology Engineering Laboratory Tsinghua-Berkeley Shenzhen InstituteTsinghua UniversityShenzhen 518055China Key Laboratory of Microorganism Application and Risk Control of Shenzhen Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental SafetyGraduate School at ShenzhenTsinghua UniversityShenzhen 518055China Environmental Simulation and Pollution Control State Key Joint Laboratory State Environmental Protection Key Laboratory of Microorganism Application and Risk Control(SMARC)School of EnvironmentTsinghua UniversityBeijing 100084China Division of Energy and Environment Graduate School at ShenzhenTsinghua UniversityShenzhen 518055China

Ozone(O3)is widely used in drinking water disinfection and wastewater ***,when applied to bromide-containing water,ozone induces the formation of bromate,which is *** previous study found±at graphene oxide(GO)can enhance the degradation efficiency of micropollutants during ***,in this study,GO was found to promote bromate formation during ozonation of bromide-containing waters,with bromate yields from the O3/GO process more than twice those obtained using ozone *** promoted bromate formation was attributed to increased hydroxyl radical production,as confirmed by the significant reduction(almost 75%)in bromate yield after adding t-butanol(TBA).Cerium oxide(less tfian 5 mg/L)supported on reduced GO(xCeO2/RGO)significantly inhibited bromate formation during ozonation compared with reduced GO alone,and the optimal Ce atomic percentage(x)was determined to be 0.36%,achieving an inhibition rate of approximately 73%.Fourier transform infrared(FT-IR)spectra indicated the transformation of GO into RGO after hydrothermal treatment,and transmission electron microscope(TEM)results showed that CeO2 nanoparticles were well dispersed on the RGO *** X-ray photoelectron spectroscopy(XPS)spectra results demonstrated that the Ce^3+/Ce^4+ratio in xCeO2/RGO was almost 3-4 times higher than that in pure CeO2,which might be attributed to the charge transfer effect from GO to ***,Ce+on thexCeO2/RGO surface could quench Br-and BrO-to further inhibit bromate ***,0.36CeO2/RGO could also enhance the degradation efficiency of N,N-diethyl-zn-toluamide(DEET)in synthetic and reclaimed water during ozonation.

关键词： Bromate Catalytic ozonation Graphene oxide Cerium dioxide

Quantitative analysis of microstructure of carbon materials by HRTEM

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中国有色金属学会会刊：英文版 2006年第B2期16卷 796-803页

作者： YANG Jan-he cheng Shu-hui WANG Xia ZHANG zhuo LIU Xiao-rong TANG Guo-hua Department of Materials Science and Engineering Shanghai Institute of Technology Shanghai 200235 China School of Chemical Engineering East China University of Science and Technology Shanghai 200000 China

The main object of the present research is to make a quantitative evaluation on the microstructure of carbon materials in terms of microcrystal. The digitized images acquired from finely pulverized carbon materials under HRTEM at a high magnification were processed by the image processing software so as to extract the fringes of (002) lattice of graphite crystal from the background image, and an FFT-IFFT filtering operation was performed followed by processes as binarization for the image and skeletonization for the fringes. A set of geometrical parameters including position, length and orientation was set up for every lattice fringe by calculating the binarized image. Then, the above obtained fringe parameters were put into an algorithm, which was especially developed for such fringe images so as to find fringes that could be regarded as those belonged to one single graphite microcrystal. The fringe was subjected sequentially to comparing procedures with every other fringe on aspects as parallelism, relative position and spacing, and the above comparisons were repeated till the last fringe. Eventually, the microcrystal size, its stacking number, and the distribution of the microcrystal in the whole sample, as well as other related structure information of such microcrystal in carbon materials were statistically calculated. Such microstructure information at nanometer level may contribute greatly to the interpretation of the properties of carbon materials and a better correlation with the same macrostructure.

关键词：碳材料微晶显微结构定量分析 HRTEM

Hydroxysafflor yellow A improves learning and memory in a rat model of vascular dementia by increasing VEGF and NR1 in the hippocampus

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Neuroscience Bulletin 2014年第3期30卷 417-424页

作者： Nan Zhang Mengya Xing Yiyi Wang Hao Liang zhuo Yang Fudong Shi Yan cheng Department of Neurology Tianjin Medical University General Hospital Tianjin Neurological Institute Key Laboratory of Post-traumatic Neuro-repair and Regeneration in the Central Nervous System Ministry of Education Tianjin Key Laboratory of Injuries Variations and Regeneration of the Nervous System Tianjin Haihe Hospital Nankai University

Hydroxysafflor yellow A （HSYA） has angiogenesis- regulating and neuro-protective effects, but its effects on vascular dementia （VaD） are unknown. In this study, 30 adult Sprague-Dawley rats were. randomly allocated to five groups： normal, sham-operation, VaD alone （bilateral carotid artery occlusion）, VaD plus saline （control）, and VaD plus HSYA. One week after operation, the HSYA group received one daily tail-vein injection of 0.6 mg/100 g HSYA for two weeks. Five weeks after operation, the spatial memory of all five groups was evaluated by the water maze task, and synaptic plasticity in the hippocampus was assessed by the long-term potentiation （LTP） method. Vascular endothelial growth factor （VEGF） and N-methyi-D- aspartic acid receptor 1 （NR1） expression in the hippocampus was detected via Western blot. We found that, compared with the group with VaD alone, the group with HSYA had a reduced escape latency in the water maze （P 〈0.05）, and the LTP at CA3- CA1 synapses in the hippocampus was enhanced （P 〈0.05）. Western blot in the late-phase VaD group showed slight up-regulation of VEGF and down- regulation of NR1 in the hippocampus, while HSYA significantly up-regulated both VEGF and NRI. These results suggested that HSYA promotes angiogenesis and increases synaptic plasticity, thus improving spatial learning and memory in the rat model of VaD.

关键词： vascular dementia hydroxysafflor yellow A long-term potentiation NMDA receptor vascular endothelial growth factor

Electrochemical process of sulfur in carbon materials from electrode thickness to interlayer

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Journal of Energy Chemistry 2019年第4期28卷 119-124页

作者： Xiaonan Tang Zhenhua Sun Huicong Yang Haitao Fang Fei Wei Hui-Ming cheng Shuping zhuo Feng Li School of Chemical Engineering Shandong University of Technology Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences School of Materials Science and Engineering University of Science and Technology of China School of Materials Science and Engineering Harbin Institute of Technology Department of Chemical Engineering Tsinghua University Tsinghua-Berkeley Shenzhen Institute Tsinghua University

Lots of efforts have been done on different porous carbon materials as cathode for Lithium–sulfur(Li–S)battery. However, seldom researches have been done on the relationship between cathode thickness and electrochemical performance. Our work investigates the relation between electrochemical performance and cathode thickness with typical porous carbon materials. We explain the phenomenon that only a modest cathode thickness can have the most adequate electrochemical reaction trend through the aspect of thermodynamics(chemical potential) so that the best electrochemical performance can be ***, interlayer can remit the shuttle effect but hinder the lithium ion diffusion process simultaneously. And we verify the effect of interlayer thickness on the shuttle effect and lithium ion diffusion process.

关键词： Lithium-sulfur battery Electrochemical reaction Cathode thickness Chemical potential Ion diffusion

An indicator-guided photo-controlled drug delivery system based on mesoporous silica/gold nanocomposites

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Nano Research 2015年第6期8卷 1893-1905页

作者： Guofeng Luo Weihai Chen Huizhen Jia Yunxia Sun Han cheng Renxi zhuo Xianzheng Zhang Key Laboratory of Biomedical Polymers of Ministry of Education & Department of Chemistry Wuhan University Wuhan 430072 China

A mesoporous silica/gold （MSN/Au） nanocomposite was designed for photo- controlled drug delivery targeted specifically at tumor cells. The MSN/Au nanocomposite was composed of MSN-based drug carriers and gold nanoparticle （AuNP）-based indicators. While the MSN-based drug carrier was a mesoporous silica nanoparticle immobilized with photo-switchable azobenzene （Azo） moieties, the AuNP-based indicator was a fluorescence-quenched AuNP modified with a matrix metalloproteinase （MMP） substrate and poly（ethylene glycol）. The two kinds of nanoparticles were connected by an α,β cyclodextrin （α,β CD） dimer ＂bridge.＂ In vitro studies demonstrated that the nanocomposite specifically interacted with tumor sites overexpressing MMP-2, which enabled guidance of the subsequent UV light irradiation for releasing entrapped drugs. Through integration of the AuNP-based indicator and the MSN-based drug carrier, the MSN/Au nanocomposite could precisely localize the released drug to tumor sites, thereby significantly improving therapeutic efficacy.

关键词： MSN/Au nanocomposite photo-controlled MMP-2 sensitive drug delivery tumor therapy

Determination of ephedrine and codeine in human urine by cation-selective exhaustive injection and sweeping micellar electrokinetic chromatography

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Chinese Chemical Letters 2009年第1期20卷 84-87页

作者： Li Jun Li Si Guang Li Hai Yan Li zhuo Cai Hao cheng Department of Biological and Chemical Engineering Guangxi University of Technology Liuzhou 545006 China College of Chemistry and Chemical Engineering Guangxi University Nanning 530004 China Zhongshan School of Medicine Sun-Yat-Sen University Guangzhou 510080 China

A sensitive method for the determination of ephedrine and codeine in human urine by capillary electrophoresis （CE） was described. In order to improve the sensitivity, two online concentration techniques including cation-selective exhaustive injection （CSEI） and sweeping micellar electrokinetic chromatography （sweeping-MEKC） were used. Under the optimum conditions, the detection limits （S/N = 3） were 0.10 μg/L for ephedrine and 0.80 μg/L for codeine. This method was successfully applied to real urine sample analysis.

关键词： Cation-selective exhaustive injection Sweeping miceUar electrokinetic chromatography Ephedrine Codeine

Decay characters of charges on an insulator surface after different types of discharge

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Plasma Science and Technology 2017年第7期19卷 93-101页

作者： cheng PAN Ju TANG Dibo WANG Yi LUO Ran zhuo Mingli FU School of Electrical Engineering Wuhan University Wuhan 430072 People＇s Republic of China State Key Laboratory of Power Transmission Equipment ＆ System Security and New Technology Chongqing University Chongqing 400044 People＇s Republic of China Electric Power Research Institute China Southern Power Grid Guangzhou 510080 People＇s Republic of China

In an insulating system including solid and gas dielectrics, discharge type has a strong impact on charge accumulation at the interface between two dielectrics, and hence charge decay. In order to clarify the influence, a surface charge measurement system was constructed, and three types of discharge, i.e. surface discharge, and low intensity and high intensity coronas, were introduced to cause surface charge accumulation. The decay behavior of surface charges after different types of discharge was obtained at various temperatures. It was found that total surface charges monotonically decreased with time, and the decay rate became larger as temperature increased. However, after a surface discharge or a high intensity corona, surface charge density in the local area appeared to fluctuate during the decay process. Compared with this, the fluctuation of surface charge density was not observed after a low intensity corona. The mechanisms of surface charge accumulation and decay were analysed. Moreover, a microscopic physical model involving charge production, accumulation, and decay was proposed so that the experimental results could be explained.

关键词： surface discharge corona surface charge accumulation surface charge decay,insulator

Modeling of organic pollutant destruction in a stirred tank reactor by ozonation

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Journal of Environmental Sciences 2001年第4期13卷 449-452页

作者： cheng Jiang YANG zhuo-ru CHEN Huan-qin KUO C.H. ZAPPI E.M. College of Chemical Engineering South China University of TechnologyGuangzhou 510641China Swalm School of Chemical Engineering Mississippi State UniversityMS 39762StarkvilleUSA

Destruction of organic contaminants in water by ozonation is a gas-liquid process which involves ozone mass transfer and fast irreversible chemical reactions. Ozonation reactor design and process optimizing require the modeling of the gas-liquid interactions within the reactor. In this paper a theoretical model combining the fluid dynamic and reaction kinetic parameters is proposed for predicting the destruction rates of organic pollutants in a semi-batch stirred-tank reactor by ozonation. A simple expression for the enhancement factor as our previous work has been applied to evaluate the chemical mass transfer coefficient in ozone absorption. 2,4-dichlorophenol (2,4-DCP) and 2,6-DCP or their mixture are chosen as the model compounds for simulating, and the predicted DCP concentrations are compared with some measured data.

关键词： dichlorophenol destruction ozonation stirred-tank reactor enhancement factor