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Particles attrition of binary mixtures in the coal-fueled chemical looping system based on fluidized bed

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Particuology 2024年第3期86卷 281-290页

作者： Heyu Li Zhe sun Yan cao Guangzhou Institute of Energy Conversion Chinese Academy of SciencesGuangzhou 510640China University of Chinese Academy of Sciences Bejing 100049China CAS Key Laboratory of Renewable Energy Guangzhou 510640China Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development Guangzhou 510640China College of Chemistry and Chemical Engineering Anhui UniversityHefei230601China

In this work,a reactive air jet attrition device with auto-recording and collection of elutriated fines was *** established insights into the physiochemical interaction and further correlated attrition behaviors between char and oxygen carriers under various operation *** attrition rate increased by over 110% upon the introduced CO_(2),which brought in the significant effect of thermo-chemical stress,similarly in effects of the increased char addition ratio and the decreased sizes of char or hematite in different *** the char-hematite co-attrition process,the elutriated carbon loss of char with poor mechanical strength was found to be over 10%,while the reactive iron loss of hematite was found to be 6.3%,and was enriched in elutriated *** reaction-derived thermochemical stress and the collision-derived mechanical stress jointly controls the particle attrition during the cyclic transformation of oxygen carrier particles in coal-fueled chemical looping fluidization,especially sig-nificant in its reduction stage.

关键词： Attrition Binary species Chemical looping Oxygen carrier CO_(2)capture

Nonlinear dynamic behavior of a flexible asymmetric aero-engine rotor system in maneuvering flight

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Chinese Journal of Aeronautics 2020年第10期33卷 2633-2648页

作者： Tian GAO Shuqian cao Yongtao sun Department of Mechanics Tianjin UniversityTianjin 300354China Tianjin Key Laboratory of Nonlinear Dynamics and Control Tianjin 300354China National Demonstration Center for Experimental Mechanics Education Tianjin UniversityTianjin 300354China

Aero-engine rotor systems installed in aircraft are considered to have a base *** this paper,a flexible asymmetric rotor system is modeled considering the nonlinear supports of ball bearings and Squeeze Film Dampers(SFDs),and the dynamic characteristics of the rotor system under maneuvering flight are systematically *** of the translational accelerative motions,the angular motions and the pitching flight with combined translational and angular motions on nonlinear dynamic behavior of the rotor system are *** results show that,due to the nonlinear coupled effects among the rotor,ball bearings and SFDs,within the first bending resonance region,responses of the rotor show obvious nonlinear characteristics such as bistable phenomenon,amplitude jumping phenomenon and non-synchronous *** acceleration motion of the aircraft leads to axis offset of the rotor system and thus results in the reduction and the final disappearance of the bistable rotating speed *** pitching angular motion mainly affects rotational vibration of the rotor system,and thus further induces their transverse *** the pitching flight with combined translational and angular motions,a critical flight parameter is found to correspond to the conversion of two steady responses of the rotor system,in which one response displays small amplitude and synchronous vibration,and the other shows large amplitude and non-synchronous vibration.

关键词： Aero-engine rotor system Ball bearings Maneuvering flight Nonlinear dynamics Squeeze film dampers

Day-ahead scheduling based on reinforcement learning with hybrid action space

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Journal of Systems Engineering and Electronics 2022年第3期33卷 693-705页

作者： cao Jingyu DONG Lu sun Changyin School of Automation Southeast UniversityNanjing 210096China School of Cyber Science and Engineering Southeast UniversityNanjing 211189China

Driven by the improvement of the smart grid,the active distribution network(ADN)has attracted much attention due to its characteristic of active *** making full use of electricity price signals for optimal scheduling,the total cost of the ADN can be ***,the optimal dayahead scheduling problem is challenging since the future electricity price is ***,in ADN,some schedulable variables are continuous while some schedulable variables are discrete,which increases the difficulty of determining the optimal scheduling *** this paper,the day-ahead scheduling problem of the ADN is formulated as a Markov decision process(MDP)with continuous-discrete hybrid action ***,an algorithm based on multi-agent hybrid reinforcement learning(HRL)is proposed to obtain the optimal scheduling *** proposed algorithm adopts the structure of centralized training and decentralized execution,and different methods are applied to determine the selection policy of continuous scheduling variables and discrete scheduling *** simulation experiment results demonstrate the effectiveness of the algorithm.

关键词： day-ahead scheduling active distribution network(ADN) reinforcement learning hybrid action space

Caffeine Exposure Causes Immune Dysfunction and Intrauterine Growth Restriction Retardation in Rats

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Biomedical and Environmental Sciences 2022年第2期35卷 170-173页

作者： ZHANG Wen Zhong sun Na Na HU Yang cao yu Amber Sheeks Department of Safety Engineering North China Institute of Science&TechnologySanhe 065201HebeiChina Key Laboratory of Food Risk Assessment Ministry of Health China National Center for Food Safety Risk AssessmentBeijing 100021China Center for Public Health Surveillance and Information Service Chinese Center for Disease Control and PreventionBeijing 102206China Muskingum University OH 43762USA

This study was conducted to assess the effects of caffeine on the dam and the physical development of rat *** Sprague-Dawley rats(20 per dose group)were administered caffeine by gavage at 0(control),5,20,and 80 mg/kg body weight(bw)daily from gestational day 6 through lactation using caffeine dissolved in *** developmental toxicity of caffeine was *** in the 80 mg/kg bw group exhibited splenic *** litter weights were significantly lower in the 20 and 80 mg/kg bw groups than the untreated control(P<0.05),with a greater reduction in the higher dose *** number of female offspring was reduced in the 20 and 80 mg/kg bw groups(P<0.05).Some of the offspring were eaten by the dam following birth,which accounted for half of the litters in the 80 mg/kg bw group(P<0.05).Offspring body weight in the 80 mg/kg bw group was lower than that in the control during the lactation period(P<0.05).Exposure to caffeine during pregnancy can cause maternal immune dysfunction and intrauterine growth restriction retardation(IUGR);the developmental toxicity of caffeine varied with gender,as females were more sensitive than *** no observed adverse effect level was 5 mg/kg bw based on the IUGR.

关键词： Immune weights offspring

Reexamination of Sexual Dimorphism and Female Reproduction in the Many-Lined sun Skink Eutropis multifasciata from China

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Asian Herpetological Research 2012年第4期3卷 265-272页

作者： yu DU Yanyan sun Chixian LIN Xiang JI Hainan Key Laboratory for Herpetological Research School of Life SciencesQiongzhou University Jiangsu Key Laboratory for Biodiversity and Biotechnology College of Life SciencesNanjing Normal University

We reexamined sexual dimorphism and female reproduction in the Many-Lined sun Skink Eutropis multifasciata from Hainan,China. Our data confirm that adults are sexually dimorphic in body size and shape,with males being the larger sex and larger in head size but shorter in abdomen length than females of the same snoutvent length(SVL). The rate at which head width increased with SVL was greater in males as opposed to the previous conclusion that the rate does not differ between the sexes. Maternal size was the main determinant of reproductive investment,with larger females generally producing more,as well as larger,offspring. Females produced up to nine offspring per litter as opposed to the previously reported 2–7. Most females gave birth between March and August,a time period approximately four months longer than that(May–June) reported previously. Females with a higher fecundity tended to produce smaller offspring as opposed to the previous conclusion that females do not tradeoff offspring size against number. Litter size,neonate mass and litter mass remained remarkably constant among years,and litter mass was more tightly related to female body size than litter size or neonate mass. Smaller females could produce relatively heavier litters without a concomitant reduction in postpartum body condition.

关键词： Scincidae Eutropis multifasciata sexual dimorphism litter size neonate size reproductive output offspring size-number trade-off

Two finite difference schemes for the phase field crystal equation

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Science China Mathematics 2015年第11期58卷 2435-2454页

作者： cao HaiYan sun ZhiZhong Department of Mathematics Southeast University

The phase field crystal(PFC) model is a nonlinear evolutionary equation that is of sixth order in *** the first part of this work,we derive a three level linearized difference scheme,which is then proved to be energy stable,uniquely solvable and second order convergent in L_2 norm by the energy method combining with the inductive *** the second part of the work,we analyze the unique solvability and convergence of a two level nonlinear difference scheme,which was developed by Zhang et *** *** numerical results with comparisons are provided.

关键词： phase field crystal model nonlinear evolutionary equation finite difference scheme solvability convergence

Large scale petroleum reservoir simulation and parallel preconditioning algorithms research

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Science China Mathematics 2004年第z1期47卷 32-40页

作者： sun Jiachang cao Jianwen R & D Center for Parallel Software Institute of Software Chinese Academy of Sciences Beijing 100080 China R & D Center for Parallel Software Institute of Software Chinese Academy of Sciences Beijing 100080 China

Solving large scale linear systems efficiently plays an important role in a petroleum reservoir simulator, and the key part is how to choose an effective parallel preconditioner. Properly choosing a good preconditioner has been beyond the pure algebraic field. An integrated preconditioner should include such components as physical background, characteristics of PDE mathematical model, nonlinear solving method, linear solving algorithm, domain decomposition and parallel computation. We first discuss some parallel preconditioning techniques, and then construct an integrated preconditioner, which is based on large scale distributed parallel processing, and reservoir simulation-oriented. The infrastructure of this preconditioner contains such famous preconditioning construction techniques as coarse grid correction, constraint residual correction and subspace projection correction. We essentially use multi-step means to integrate totally eight types of preconditioning components in order to give out the final preconditioner. Million-grid cell scale industrial reservoir data were tested on native high performance computers. Numerical statistics and analyses show that this preconditioner achieves satisfying parallel efficiency and acceleration effect.

关键词： petroleum reservoir simulation, parallel preconditioning, parallel efficiency, high performance computing.

Effect Factors in Synthesis of Nicotinic Acid by Electrooxidation of 3-Picoline

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Chemical Research in Chinese Universities 2005年第6期21卷 692-696页

作者： sun Xiu-yun ZHANG yu-min cao Xue-jing ZHANG Heng-bin LI Fei XU yu-ling College of Chemistry Jilin University Changchun 130021 P. R. China Department of Applied Chemistry Jilin Institute of Chemical Technology Jilin 132022 P. R. China

In an electrolytic cell with a proton exchange membrane, nicotinic acid was synthesized at the PbO2 anode. The relationship between the current density and the potential at different concentrations of 3-picoline and sulfuric acid as well as at different temperatures was studied with polarization curves. The effects of the concentrations of sulfuric acid and 3-picoline, the anode potential and the reaction temperature on the selectivity and the current efficiency were explored. The optimum conditions were determined by orthogonal experiments. Under optimum conditions the selectivity and the current efficiency for the synthesis of nicotinic acid might reach 89% and 65%, respectively. The, concentrations of 3-picoline and nicotinic acid were analyzed with high performance liquid chromatography and the product was characterized with elemental analysis, chromatography-mass spectrometry and IR spectrometry.

关键词： 3-Picoline Nicotinic acid Electrooxidation Electroorganic synthesis

Deep Neural Network-Based 4-Quadrant Analog sun Sensor Calibration

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Space(Science & Technology) 2023年第1期3卷 193-205页

作者： Qinbo sun Jose Luis Redondo Gutiérrez Xiaozhou yu School of Astronautics Northwestern Polytechnical UniversityXi’anChina Institute of Space Systems German Aerospace CenterCologneGermany Dalian University of Technology DalianChina

Many error sources influence the calibration experiment of 4-quadrant sun sensors,making the calibration of sun sensors cumbersome and its accuracy difficult to *** continuous function on a bounded closed set can be approximated by a deep neural *** paper uses the deep neural network model to approximate the error *** data-driven training network is adopted to continuously modify the model parameters to fit the error compensation model and ensure that the accuracy reaches the target requirements after *** that the deep neural network model needs a considerable amount of data,the neural network model training is divided in 2 *** the preliminary stage,cubic surface fitting is used to generate a dataset,which is small in size and *** the completion of the initial training,the experimental data are used to fine-tune the model to achieve error *** accuracy can be improved from 1°(1σ)to 0.1°(1σ)after the incident angle of the sun sensor is *** error compensation model eliminates the loss of accuracy caused by the distortion of light spots at the edge of the field angle and provides a favorable condition for the expansion of the field angle of the 4-quadrant analog sun sensor.

关键词： neural Deep network