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Mapping soil organic matter in cultivated land based on multi-year composite images on monthly time scales

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Journal of Integrative Agriculture 2024年第4期23卷 1393-1408页

作者： Jie Song Dongsheng Yu Siwei Wang Yanhe Zhao Xin Wang Lixia Ma Jiangang Li State key laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Agricultural and Rural Bureau of Luanping County Luanping 068250China Chinese Academy of Sciences University Beijing 100049China

Rapid and accurate acquisition of soil organic matter(SOM)information in cultivated land is important for sustainable agricultural development and carbon balance *** study proposed a novel approach to predict SOM with high accuracy using multiyear synthetic remote sensing variables on a monthly *** obtained 12 monthly synthetic Sentinel-2 images covering the study area from 2016 to 2021 through the Google Earth Engine(GEE)platform,and reflectance bands and vegetation indices were extracted from these composite *** the random forest(RF),support vector machine(SVM)and gradient boosting regression tree(GBRT)models were tested to investigate the difference in SOM prediction accuracy under different combinations of monthly synthetic *** showed that firstly,all monthly synthetic spectral bands of Sentinel-2 showed a significant correlation with SOM(Penvironmental variables were grouped in accordance with the four quarters of the year,the first quarter and the fourth quarter showed good performance,and any combination of three quarters was similar in estimation *** overall best performance was observed when all monthly synthetic variables were incorporated into the ***,among the three models compared,the RF model was consistently more accurate than the SVM and GBRT models,achieving an R^(2)value of *** for band 12 in December,the importance of the remaining bands did not exhibit significant *** research offers a new attempt to map SOM with high accuracy and fine spatial resolution based on monthly synthetic Sentinel-2 images.

关键词： soil organic matter Sentinel-2 monthly synthetic images machine learning model spatial prediction

Incorporation of source contributions to improve the accuracy of soil heavy metal mapping using small sample sizes at a county scale

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Pedosphere 2024年第1期34卷 170-180页

作者： Jie SONG Xin WANG Dongsheng YU Jiangang LI Yanhe ZHAO Siwei WANG Lixia MA State key laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Chinese Academy of Sciences University Beijing 100049China Agricultural and Rural Bureau of Luanping County Luanping 068250China

Estimating heavy metal(HM) distribution with high precision is the key to effectively preventing Chinese medicinal plants from being polluted by the native soil. A total of 44 surface soil samples were gathered to detect the concentrations of eight HMs(As, Hg, Cu, Cr, Ni, Zn, Pb, and Cd) in the herb growing area of Luanping County, northeastern Hebei Province, China. An absolute principal component score-multiple linear regression(APCS-MLR) model was used to quantify pollution source contributions to soil HMs. Furthermore, the source contribution rates and environmental data of each sampling point were simultaneously incorporated into a stepwise linear regression model to identify the crucial indicators for predicting soil HM spatial distributions. Results showed that 88% of Cu, 72% of Cr, and 72% of Ni came from natural sources;50% of Zn, 49% of Pb, and 59% of Cd were mainly caused by agricultural activities;and 44% of As and 56% of Hg originated from industrial activities. When three-type(natural, agricultural, and industrial) source contribution rates and environmental data were simultaneously incorporated into the stepwise linear regression model, the fitting accuracy was significantly improved and the model could explain 31%–86% of the total variance in soil HM concentrations. This study introduced three-type source contributions of each sampling point based on APCS-MLR analysis as new covariates to improve soil HM estimation precision, thus providing a new approach for predicting the spatial distribution of HMs using small sample sizes at the county scale.

关键词： absolute principal component score-multiple linear regression Chinese herbal medicine influencing factors spatial distribution stepwise multiple regression

Kinetic studies on the dimerization of isobutene with Ni/Al_2O_3 as a catalyst for reactive distillation process

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Chinese Journal of Chemical Engineering 2015年第3期23卷 520-527页

作者：童立威陈立芳叶银梅漆志文 Max Planck Partner Group at the State key laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and Technology School of Resources and environmental Engineering East China University of Science and Technology

Isooctane is a promising gasoline additive that could be produced by dimerization of isobutene(IB) with subsequent *** this work,the dimerization of IB has been carried out in a batch reactor over a temperature range of 338-383 K in the presence of laboratory prepared Ni/Al_2O_3 as a catalyst and n-pentane as *** influence of various parameters such as temperature,catalyst loading and initial concentration of IB was examined.A Langmuir-Hinshelwood kinetic model of IB dimerization was established and the parameters were estimated on the basis of the measured *** feasibility of oligomerization of IB based on the reactive distillation was simulated in ASPEN PLUS using the kinetics *** simulation results showed that the catalyst of Ni/Al_2O_3 had higher selectivity to diisobutene(DIB) and slightly lower conversion of IB than ion exchange resin in the absence of polar substances.

关键词： Isobutene Oligomerization Catalyst Kinetic modeling Reactive distillation

Sorption of chlorophenols onto fruit cuticles and potato periderm

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Journal of environmental Sciences 2012年第4期24卷 675-681页

作者： Yungui Li Yingqing Deng Baoliang Chen Department of environmental Science Zhejiang UniversityHangzhou 310058China Zhejiang Provincial key laboratory of Organic Pollution Process and Control Hangzhou 310058China Department of environmental Engineering Southwest University of Science and TechnologyMianyang 621010China

To better understand the interaction mechanisms of plant surfaces with polar organic compounds, sorption of 4-chlorophenol, 2,4- dichlorophenol, and 2,4,6-trichlorophenol by fruit cuticles （i.e., tomato, apple, and pepper）, and potato tuber periderm were investigated. The roles of cuticular components （waxes, cutin, cutan and sugar） on sorption of chlorophenols are quantitatively compared. Cutin and waxes govern the sorption capacity of bulk apple cuticle by hydrophobic interactions. Potato periderm with highest sugar content exhibits the lowest sorption capability for the chlorophenols. With the increase of hydrophobicity （i.e., Kow ） of sorbate, the relative contribution of lipophilic components （wax, cutin and cutan） on total sorption increases, however, the ratios of Koc to Kow decreases due to increasing ionization degree of sorbates.

关键词： potato periderm fruit cuticle chlorophenol sorption waxes cutin

Effects of persulfate-assisted hydrothermal treatment of municipal sludge on aqueous phase characteristics and phytotoxicity

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Journal of environmental Sciences 2023年第4期126卷 163-173页

作者： Guangchun Shan Weiguang Li Yujie Zhou Shanshan Bao Lin Zhu Wenbing Tan State key laboratory of environmental Criteria and Risk Assessment and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater PollutionChinese Research Academy of Environmental SciencesBeijing 100012China State key laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin 150090China key laboratory of Water Management and Water Security for Yellow River Basin of Ministry of Water Resources(Under Construction) Yellow River Engineering Consulting Co.LtdZhengzhou 450003China

Hydrothermal technology (HT) has received much attention in recent years as a process to convert wet organic waste into *** aqueous phase (HTAP) produced by this process is still a burden and has become a bottleneck issue for HT process *** this study,we provide the?rst investigation of the HTAP characteristics,phytotoxicity,and their correlation with persulfate (PS)(PS,2.0 mmol/g TS)-assisted municipal sludge *** results showed that PS accelerated the hydrolysis of protein substances and increased the concentration of NH_(4)^(+)by 13.4%to 190.5%and that of PO_(4)^(3-)by 24.2%to 1103.7%in HTAP at hydrothermal temperatures of 120 to 240℃.PS can reduce the phytotoxicity of HTAP by reducing aldehydes,ketones,N heterocyclic compounds,and particle size and by increasing its humi?cation *** maximum values of the root length and biomass of pakchoi(Brassica chinensis L.) seedlings occurred when electrical conductivity was 0.2 mS/cm of *** work provided a new strategy for the selection and design of HTAP management strategies.

关键词： Hydrothermal technology Aqueous phase characteristics Pakchoi Seedlings Phytotoxicity

Synthesis and Application of Polyurethane Modified Organic Silicone Wet Rubbing Fastness Improver

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Journal of Donghua University(English Edition) 2015年第3期32卷 515-519页

作者：仝东凤刘学董朝红刘杰 College of Chemical and environmental Engineering Qingdao University key laboratory of Special Textile Processing technology of Shandong Province

Polyurethane modified organic silicone was successfully prepared from hydroxyl-terminated polyether modified silicone,toluene-2,4-diisocyanate( TDI), and NaHSO3. The chemical structure of the polyurethane modified organic silicone was characterized by FT-IR and1H-NMR. The polymer film on the cotton surface was investigated by scanning electron microscopy( SEM) and the results showed that a thin polymer film was successfully formed. The FT-IR of treated cotton fabrics indicated that hydroxyl( OH) of cellulose fiber and isocyanate group( NCO)of the polyurethane modified organic silicone has formed covalent cross-linking. X-ray diffraction( XRD) analysis revealed that the crystalline region of treated cotton fabrics wasn't changed. The wet rubbing fastness of treated cotton fabrics was increased by approximately rating 1 on average. There was little change of DE values for the polyurethane modified organic silicone. The softness was improved significantly.

关键词： modified silicone wet rubbing fastness cotton fabric application

Microaerobic Fe (Ⅱ) oxidation coupled to carbon assimilation processes driven by microbes from paddy soil

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Science China Earth Sciences 2019年第11期62卷 1719-1729页

作者： Xiaomin LI Shan MOU Yating CHEN Tongxu LIU Jun DONG Fangbai LI SCNU environmental Research Institute Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety&MOE Key Laboratory of Environmental Theoretical ChemistrySouth China Normal UniversityGuangzhou 510006China Guangdong key laboratory of Integrated Agri-Environment Pollution Control and Management Guangdong Institute of Eco-Environmental Science&TechnologyGuangzhou 510650China School of Micro-Electronics and Solid-State Electronics University of Electronic Science and Technology of ChinaChengdu 610054China Institute for Disaster Management and Reconstruction Sichuan University-Hong Kong Polytechnic UniversityChengdu 610207China

Microaerobic Fe(Ⅱ) oxidation process at neutral pH, driven by microbes can couple to carbon assimilation process in iron-rich freshwater and marine environments;however, few studies report such coupled processes in paddy soil of the critical zone in South China. In this study, rhizosphere soil from flooded paddy field was used as the inoculum to enrich the microaerophilic Fe(Ⅱ)-oxidizing bacteria(FeOB) in gradient tubes with different Fe(Ⅱ) substrates(FeS and FeCO_3) and ^(13)C-biocarbonate as inorganic carbon source to track the carbon assimilation. Kinetics of Fe(Ⅱ) oxidation and biomineralization were analyzed, and the composition and abundance of the microbial community were profiled using 16 S rRNA gene-based highthroughput sequencing. Results showed that microbial cell bands were formed 0.5–1.0 cm below the medium surface in the inoculated tubes with Fe(Ⅱ) substances, while no cell band was found in the non-inocula controls. The protein concentrations in the cell bands reached the highest values at 18.7–22.9 mg m^L(-1) on 6 d in the inocula tubes with Fe(Ⅱ) substrates. A plateau of the yields of ^(13)C-biocarbonate incorporation was observed during 6–15 d at 0.44–0.54% and 1.61–1.98% in the inocula tubes with FeS and FeCO_3, respectively. The inocula tube with FeS showed a higher Fe(Ⅱ) oxidation rate of 0.156 mmol L^(-1) d^(-1) than that with FeCO_3(0.106 mmol L^(-1) d^(-1)). Analyses of X-ray diffraction and scanning electron microscopy with energy-dispersive X-ray spectroscopy revealed that amorphous iron oxide was formed on the surface of rod-shaped bacteria after Fe(Ⅱ) *** to the agar only control, the abundances of Clostridium and Pseudogulbenkiania increased in the inocula tube with FeS,while those of Vogesella, Magnetospirillum, Solitalea, and Oxalicibacterium increased in the inocula tube with FeCO_3, all of which might be the potential microaerophilic FeOB in paddy soil. The findings in this study suggest that microbes that couple micro

关键词： Microaerobic Fe(Ⅱ)oxidation Paddy soil Carbon assimilation Microorganism

Simultaneous removal of chromium and arsenate from contaminated groundwater by ferrous sulfate:Batch uptake behavior

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Journal of environmental Sciences 2011年第3期23卷 372-380页

作者： Xiaohong Guan Haoran Dong Jun Ma Irene M. C. Lo State key laboratory of Urban Water Resource and Environment Harbin Institute of Technology Harbin 150090 China Department of Civil and environmental Engineering The Hong Kong University of Science and Technology Hong Kong 999077 China

Chromium and/or arsenate removal by Fe（Ⅱ） as a function of pH, Fe（Ⅱ） dosage and initial Cr（Ⅵ）/As（Ⅴ） ratio were examined in batch tests. The presence of arsenate reduced the removal efficiency of chromium by Fe（Ⅱ）, while the presence of chromate significantly increased the removal efficiency of arsenate by Fe（Ⅱ） at pH 6-8, In the absence of arsenate, chromium removal by Fe（Ⅱ） increased to a maximum with increasing pH from 4 to 7 and then decreased with a further increase in pH. The increment in Fe（Ⅱ） dosage resulted in an improvement in chromium removal and the improvement was more remarkable under alkaline conditions than that under acidic conditions. Chromium removal by Fe（Ⅱ） was reduced to a larger extent under neutral and alkaline conditions than that under acidic conditions due to the presence of 10 μtmol/L arsenate. The presence of 20 μmol/L arsenate slightly improved chromium removal by Fe（Ⅱ） at pH 3.9-5,8, but had detrimental effects at pH 6.7-9.8. Arsenate removal was improved significantly at pH 4-9 due to the presence of 10μmol/L chromate at Fe（Ⅱ） dosages of 20-60 μmol/L. Elevating the chromate concentration from 10 to 20μmol/L resulted in a further improvement in arsenate removal at pH 4.0-4.6 when Fe（Ⅱ） was dosed at 30-60 μmol/L.

关键词： chromium removal arsenate removal ferrous iron groundwater treatment

Adaptive Multi-Step Evaluation Design With Stability Guarantee for Discrete-Time Optimal Learning Control

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IEEE/CAA Journal of Automatica Sinica 2023年第9期10卷 1797-1809页

作者： Ding Wang Jiangyu Wang Mingming Zhao Peng Xin Junfei Qiao IEEE Faculty of Information technology the Beijing Key Laboratory of Computational Intelligence and Intelligent Systemthe Beijing Laboratory of Smart Environmental Protectionand the Beijing Institute of Artificial IntelligenceBeijing University of TechnologyBeijing 100124China

This paper is concerned with a novel integrated multi-step heuristic dynamic programming(MsHDP)algorithm for solving optimal control *** is shown that,initialized by the zero cost function,MsHDP can converge to the optimal solution of the Hamilton-Jacobi-Bellman(HJB)***,the stability of the system is analyzed using control policies generated by ***,a general stability criterion is designed to determine the admissibility of the current control *** is,the criterion is applicable not only to traditional value iteration and policy iteration but also to ***,based on the convergence and the stability criterion,the integrated MsHDP algorithm using immature control policies is developed to accelerate learning efficiency ***,actor-critic is utilized to implement the integrated MsHDP scheme,where neural networks are used to evaluate and improve the iterative policy as the parameter ***,two simulation examples are given to demonstrate that the learning effectiveness of the integrated MsHDP scheme surpasses those of other fixed or integrated methods.

关键词： Adaptive critic artificial neural networks Hamilton-Jacobi-Bellman(HJB)equation multi-step heuristic dynamic programming multi-step reinforcement learning optimal control