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Experimental study on the activation of coal gasification fly ash from industrial CFB gasifiers

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Chinese Journal of Chemical Engineering 2024年第1期65卷 8-18页

作者： Qiyao Yang Xiaobin Qi Qinggang Lyu zhiping Zhu North China Electric Power University Beijing 102206China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China Shanxi Key Laboratory of Coal Flexible Combustion and Thermal Conversion Datong 037000China University of Chinese Academy of Sciences Beijing 100049China Shanxi Engineering Research Center of Coal Clean Efficient Combustion and GasificationDatong 037000China

Coal gasification fly ash(CGFA)is an industrial solid waste from the coal circulating fluidized bed(CFB)gasification process,and it needs to be effectively disposed to achieve sustainable development of the *** realize the application of CGFA as a precursor of porous carbon materials,the physicochemical properties of three kinds of CGFA from industrial CFB gasifiers are ***,the activation potential of CGFA is acquired via steam activation experiments in a tube furnace ***,the fluidization activation technology of CGFA is practiced in a bench-scale CFB test rig,and its advantages are *** results show that CGFA is characterized by a high carbon content in the range of 54.06%–74.09%,an ultrafine particle size(d50:16.3–2..1 μm),and a relatively developed pore structure(specific surface area SSA:139.2.–551.97 m^(2.·g^(-1)).The proportion of micropores in CGFA increases gradually with the coal *** activation experiments show that the pore development of CGFA mainly includes three stages:initial pore development,dynamic equilibrium between micropores and mesopores and pore *** SSA of lignite fly ash(LFA),subbituminous fly ash(SBFA)and anthracite fly ash(AFA)is maximally increased by 105%,13%and 72.after steam activation;the order of the largest carbon reaction rate and decomposition ratio of steam among the three kinds of CGFA is SBFA>LFA>*** the ratio of oxygen to carbon during the fluidization activation of LFA is from 0.09 to 0.19,the carbon conversion ratio increases from 14.4%to 2..8%and the cold gas efficiency increases from 6.8%to 10.2..The SSA of LFA increases by up to 53.9%during the fluidization activation process,which is mainly due to the mesoporous *** to steam activation in a tube furnace reactor,fluidization activation takes an extremely short time(seconds)to achieve the same activation *** is expected to further improve the activation effect of LFA by regulating the carbo

关键词： Circulating fluidized bed Coal gasification fly ash Steam activation Pore structure evolution Fluidization activation

A dynamical neural network approach for distributionally robust chance-constrained Markov decision process

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Science China Mathematics 2024年第6期67卷 1395-1418页

作者： Tian Xia Jia Liu zhiping Chen School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an710049China

In this paper,we study the distributionally robust joint chance-constrained Markov decision *** the logarithmic transformation technique,we derive its deterministic reformulation with bi-convex terms under the moment-based uncertainty *** cope with the non-convexity and improve the robustness of the solution,we propose a dynamical neural network approach to solve the reformulated optimization *** results on a machine replacement problem demonstrate the efficiency of the proposed dynamical neural network approach when compared with the sequential convex approximation approach.

关键词： Markov decision process chance constraints distributionally robust optimization moment-based ambiguity set dynamical neural network

Visible-light-induced Synthesis of Organic Peroxides via Decarboxylative Couplings of Carboxylic Acids,Alkenes and tert-Butyl Hydroperoxide

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Chemical Research in Chinese Universities 2024年第5期40卷 863-873页

作者： HUANG Qiuwei LOU Chenhao LV Leiyang LI zhiping Key Laboratory of Advanced Light Conversion Materials and Biophotonics School of Chemistry and Life ResourcesRenmin University of ChinaBeijing100872P.R.China

Herein,we present a photoinduced,CeCl_(3)-catalyzed three-component decarboxylative reaction that couples carboxylic acids,alkenes and tert-butyl hydroperoxide for the formation of various organic *** ligand-to-metal charge transfer(LMCT)excitation mode allows the decarboxylative alkylation-peroxidation reaction to occur under mild conditions,and is well applicable to primary,secondary and tertiary carboxylic acids and styrene derivatives.

关键词： Visible-light catalysis Difunctionalization Carboxylic acid Alkene Organic peroxide

Flexible, thermal processable, self-healing, and fully bio-based starch plastics by constructing dynamic imine network

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Green Energy & Environment 2024年第10期9卷 1610-1618页

作者： Xiaoqian Zhang Haishan Zhang Guowen Zhou zhiping Su Xiaohui Wang State Key Laboratory of Pulp and Paper Engineering South China University of Technology

The serious environmental threat caused by petroleum-based plastics has spurred more researches in developing substitutes from renewable *** is desirable for fabricating bioplastic due to its abundance and renewable ***,limitations such as brittleness,hydrophilicity,and thermal properties restrict its widespread *** overcome these issues,covalent adaptable network was constructed to fabricate a fully bio-based starch plastic with multiple advantages via Schiff base *** strategy endowed starch plastic with excellent thermal processability,as evidenced by a low glass transition temperature （Tg=2..15℃）.Through introducing Priamine with long carbon chains,the starch plastic demonstrated superior flexibility （elongation at break=45.2.） and waterproof capability （water contact angle=109.2.）.Besides,it possessed a good thermal stability and self-adaptability,as well as solvent resistance and chemical *** work provides a promising method to fabricate fully bio-based plastics as alternative to petroleum-based plastics.

关键词： Bioplastic Covalent adaptable networks Schiff base chemistry Thermal processability Self-healing

Global optimization of double protograph LDPC codes for JSCC scheme

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Science China(Information Sciences) 2024年第6期67卷 455-456页

作者： Qiwang CHEN Chen CHEN Yu-Cheng HE zhiping XU Xiamen Key Laboratory of Mobile Multimedia Communications College of Information Science and EngineeringHuaqiao University Key Laboratory of Underwater Acoustic Communication and Marine Information Technology (Xiamen University) Ministry of Education School of Ocean Information Engineering Jimei University

A double low-density parity-check (D-LDPC) coding system was proposed in[1]as a typical joint source-channel coding(JSCC) scheme[1–5].In this system,two LDPC coding matrices perform source and channel coding,*** important concept in a D-LDPC coding system is the introduction of a linking matrix between the check nodes (CNs)of the source coding matrix and the variable nodes (VNs) of the channel LDPC coding matrix.

关键词： JOINT SOURCE DESIGN

The GNSS PWV retrieval using non-observation meteorological parameters based on ERA5 and its relation with precipitation

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Geodesy and Geodynamics 2024年第3期15卷 302-313页

作者： Weifeng Yang zhiping Chen Kaiyun Lv Pengfei Xia Tieding Lu School of Surveying and Geoinformation Engineering East China University of TechnologyNanchang 330013China Key Laboratory of Mine Environmental Monitoring and Improving around Poyang Lake of Ministry of Natural Resources East China University of TechnologyNanchang 330013China State Key Laboratory of Geodesy and Earth's Dynamics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430077China Jiangxi Province Engineering Research Center of Surveying Mapping and Geographic InformationNanchang 330025China School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China

The pressure and temperature significantly influence precipitable water vapor(PWV) retrieval. Global Navigation Satellite System(GNSS) PWV retrieval is limited because the GNSS stations lack meteorological sensors. First, this article evaluated the accuracy of pressure and temperature in 68 radiosonde stations in China based on ERA5 Reanalysis data from 2.15 to 2.19 and compared them with GPT3model. Then, the accuracy of pressure and temperature calculated by ERA5 were estimated in 5 representative IGS stations in China. And the PWV calculated by these meteorological parameters from ERA5(ERA5-PWV) were analyzed. Finally, the relation between ERA5-PWV and precipitation was deeply explored using wavelet coherence analysis in IGS stations. These results indicate that the accuracy of pressure and temperature of ERA5 is better than the GPT3 model. In radiosonde stations, the mean BIAS and MAE of pressure and temperature in ERA5 are-0.41/1.15 hpa and-0.97/2.12.K. And the mean RMSEs are 1.35 hpa and 2.87 K, which improve 74.77% and 40.58% compared with GPT3 model. The errors of pressure and temperature of ERA5 are smaller than the GPT3 model in bjfs, hksl and wuh2. and the accuracy of ERA5-PWV is improved by 18.77% compared with the GPT3 model. In addition, there is a significant positive correlation between ERA5-PWV and precipitation. And precipitation is always associated with the sharp rise of ERA5-PWV, which provides important references for rainfall prediction.

关键词： ERA5 GNSS Precipitable water vapor Precipitation Wavelet coherence analysis

Unsupervised Time Series Segmentation: A Survey on Recent Advances

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Computers, Materials & Continua 2024年第8期80卷 2657-2673页

作者： Chengyu Wang Xionglve Li Tongqing Zhou zhiping Cai College of Computer National University of Defense TechnologyChangsha410073China

Time series segmentation has attracted more interests in recent years,which aims to segment time series into different segments,each reflects a state of the monitored *** there have been many surveys on time series segmentation,most of them focus more on change point detection(CPD)methods and overlook the advances in boundary detection(BD)and state detection(SD)*** this paper,we categorize time series segmentation methods into CPD,BD,and SD methods,with a specific focus on recent advances in BD and SD *** the scope of BD and SD,we subdivide the methods based on their underlying models/techniques and focus on the milestones that have shaped the development trajectory of each *** a conclusion,we found that:(1)Existing methods failed to provide sufficient support for online working,with only a few methods supporting online deployment;(2.Most existing methods require the specification of parameters,which hinders their ability to work adaptively;(3)Existing SD methods do not attach importance to accurate detection of boundary points in evaluation,which may lead to limitations in boundary point *** highlight the ability to working online and adaptively as important attributes of segmentation methods,the boundary detection accuracy as a neglected metrics for SD methods.

关键词： Time series segmentation time series state detection boundary detection change point detection

Task-Oriented Semantic Communication with Foundation Models

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China Communications 2024年第7期21卷 65-77页

作者： Chen Mingkai Liu Minghao Zhang Zhe Xu zhiping Wang Lei Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Ministry of EducationNanjing University of Posts and TelecommunicationsNanjing 210003China School of Ocean Information Engineering Jimei UniversityXiamen 361021China Key Laboratory of Underwater Acoustic Communication and Marine Information Technology(Xiamen University) Ministry EducationXiamen 361005China

In the future development direction of the sixth generation(6G)mobile communication,several communication models are proposed to face the growing challenges of the *** rapid development of artificial intelligence(AI)foundation models provides significant support for efficient and intelligent communication *** this paper,we propose an innovative semantic communication paradigm called task-oriented semantic communication system with foundation ***,we segment the image by using task prompts based on the segment anything model(SAM)and contrastive language-image pretraining(CLIP).Meanwhile,we adopt Bezier curve to enhance the mask to improve the segmentation ***,we have differentiated semantic compression and transmission approaches for segmented ***,we fuse different semantic information based on the conditional diffusion model to generate high-quality images that satisfy the users'specific task ***,the experimental results show that the proposed system compresses the semantic information effectively and improves the robustness of semantic communication.

关键词： diffusion model foundation model joint source-channel coding task-oriented semantic communication

How Does Participation in Agricultural Cooperatives Affect the Performance of Family Farms?——Empirical Evidence from 553 Planting Family Farms in Xinjiang Corps

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Journal of Systems Science and Information 2024年

作者： zhiping HUANG Na LI Xishan Farmland The 12th Division of Xinjiang Production and Construction Corps School of Economics and Management University of Chinese Academy of Sciences

Participation in agricultural cooperative organizations is an important form of industrial chain organization expansion, but also an important way to effectively reduce industrial chain transaction costs and promote the quality and efficiency improvement of new agricultural business *** on the micro-survey data of 553 family farms in Xinjiang Corps in 2.2., this paper uses stochastic frontier approach to measure the business performance of family farms in Xinjiang Corps, and discusses the action mechanism and difference in the influence of participation in agricultural cooperative organizations on the business performance of family farms. The research shows that participation in agricultural cooperative organizations can significantly improve the business performance of family farms through such mechanisms as easing the constraints of farm credit financing, reducing the transaction costs of agricultural products, and promoting the adoption of agricultural technologies. Compared with food farms, cotton and fruit and vegetable family farms have more obvious performance improvement in participating in agricultural cooperative organizations. Moreover, participation in agricultural cooperation organizations has a stronger effect on the performance improvement of farms in northern Xinjiang. It is found that the vertical extension of the industrial chain between”family farm+agricultural cooperative organization” and network marketers, chain supermarkets, industrial leading enterprises and agricultural production and marketing enterprises is conducive to the improvement of the business performance of family farms, among which the performance improvement effect of”family farm+agricultural cooperative organization+network marketers” mode is more obvious. The research provides a scientific reference for deepening the expansion of the industrial chain organization and promoting the quality-oriented growth of family farms in the new era.

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