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Dominant woody plant species recognition with a hierarchical model based on multimodal geospatial data for subtropical forests

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Journal of Forestry Research 2024年第3期35卷 111-130页

作者： Xin chen Yujun Sun State Forestry&Grassland Administration Key Laboratory of Forest Resources&Environmental management Beijing Forestry UniversityBeijing 100083People's Republic of China

Since the launch of the Google Earth Engine(GEE)cloud platform in 2010,it has been widely used,leading to a wealth of valuable ***,the potential of GEE for forest resource management has not been fully *** extract dominant woody plant species,GEE combined Sen-tinel-1(S1)and Sentinel-2(S2)data with the addition of the National Forest Resources Inventory(NFRI)and topographic data,resulting in a 10 m resolution multimodal geospatial dataset for subtropical forests in southeast *** and texture features,red-edge bands,and vegetation indices of S1 and S2 data were computed.A hierarchical model obtained information on forest distribution and area and the dominant woody plant *** results suggest that combining data sources from the S1 winter and S2 yearly ranges enhances accuracy in forest distribution and area extraction compared to using either data source ***,for dominant woody species recognition,using S1 winter and S2 data across all four seasons was *** terrain factors and removing spatial correlation from NFRI sample points further improved the recognition *** optimal forest extraction achieved an overall accuracy(OA)of 97.4%and a maplevel image classification efficacy(mICE)of 96.7%.OA and mICE were 83.6%and 80.7%for dominant species extraction,*** high accuracy and efficacy values indicate that the hierarchical recognition model based on multimodal remote sensing data performed extremely well for extracting information about dominant woody plant *** the results using the GEE application allows for an intuitive display of forest and species distribution,offering significant convenience for forest resource monitoring.

关键词： Google Earth Engine Sentinel Forest resource inventory data Dominant woody plant species Subtropics model performance

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Efficient Removal of Phosphate from Aqueous Solutions Using Corundum-hollow-spheres Supported Caclined Hydrotalcite Porous Thin Films

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Journal of Wuhan University of Technology(materials Science) 2024年第1期39卷 44-49页

作者：刘云才 ZHU chen School of Architecture and materials Engineering Hubei Second Normal UniversityWuhan 430205China

Phosphate was removed from aqueous environment by corundum-hollow-spheres supported caclined hydrotalcite (cHT) thin films. mg-Al-CO3 hydrotalcite (HT) thin films were deposited on corundumhollow-sphere substrates by hydrothermal homogeneous precipitation at 120℃for 30-240 min and cHT thin films were obtained by annealing of the HT thin films at 500℃for 180 min. Their crystal phase, morphology and microstructure were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEm).The results show that homogeneous, well-crystallized and hierarchical flower-like thin films were deposited firmly on the surface of the corundum. The mechanism of nucleation and growth of the HT thin films was fitted well with the anion coordination polyhedron growth unit model. To determine the absorption of phosphate by this adsorbent, different bed depth (10-30 cm) and flow rate (1.0-3.0 m L/min) were examined by column experiments. The highest removal efficiency of phosphate amounted to 98.5%under optimum condition (pH=7.2). The adsorption capacity increased as the bed depth increased and decreased as the flow rate increased.

关键词： adsorption phosphate hydrotalcite corundum-hollow-sphere hydrothermal homogeneous precipitation thermal anneal

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Numerical simulation on the multiphase flow and reoxidation of the molten steel in a two-strand tundish during ladle change

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International Journal of minerals,metallurgy and materials 2024年第7期31卷 1540-1553页

作者： Jingcheng Wang Zhentong Liu Wei chen Hongliang chen Lifeng Zhang School of mechanical Engineering Yanshan UniversityQinhuangdao 066004China School of materials Science and Engineering Tianjin UniversityTianjin 300350China School of mechanical and materials Engineering North China University of TechnologyBeijing 100144China

A 3D mathematical model was proposed to investigate the molten steel–slag–air multiphase flow in a two-strand slab continuous casting(CC)tundish during ladle *** study focused on the exposure of the molten steel and the subsequent reoxidation *** exposure of the molten steel was calculated using the coupled realizable k–εmodel and volume of fluid(VOF)*** diffusion of dissolved oxygen was determined by solving the user-defined scalar(UDS)***,the user-defined function(UDF)was used to describe the source term in the UDS equation and determine the oxidation rate and oxidation *** effect of the refilling speed on the molten steel exposure and dissolved oxygen content was also *** the refilling speed during ladle change reduced the refilling time and the exposure duration of the molten ***,the elevated refilling speed enlarged the slag eyes and increased the average dissolved oxygen content within the tundish,thereby exacerbating the reoxidation *** addition,the time required for the molten steel with a high dissolved oxygen content to exit the tundish varied with the refilling *** the inlet speed was 3.0 m·s^(-1)during ladle change,the molten steel with a high dissolved oxygen content exited the outlet in a short period,reaching a maximum dissolved oxygen content of 0.000525wt%.Conversely,when the inlet speed was 1.8 m·s^(-1),the maximum dissolved oxygen content was 0.000382wt%.The refilling speed during the ladle change process must be appropriately decreased to minimize reoxidation effects and enhance the steel product quality.

关键词： tundish ladle change reoxidation multiphase flow numerical simulation

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Effect of carbon material and surfactant on ink property and resulting surface cracks of fuel-cell microporous layers

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Chinese Journal of Chemical Engineering 2024年第5期69卷 1-12页

作者： Zhekun chen Weitong Pan Longfei Tang Xueli chen Fuchen Wang Engineering Research Center of Resource Utilization of Carbon-containing Waste with Carbon Neutrality Ministry of EducationEast China University of Science and TechnologyShanghai 200237China Key Laboratory of Pressure Systems and Safety Ministry of EducationEast China University of Science and TechnologyShanghai 200237China

Ensuring the consistency of electrode structure in proton-exchange-membrane fuel cells is highly desired yet challenging because of wide-existing and unguided cracks in the microporous layer(mPL). The first thing is to evaluate the homogeneity of mPL with cracks quantitatively. This paper proposes the homogeneity index of a full-scale mPL with an area of 50 cm~2, which is yet to be reported in the literature to our knowledge. Besides, the effects of the carbon material and surfactant on the ink and resulting mPL structure have been studied. The ink with a high network development degree produces an mPL with low crack density, but the ink with high PDI produces an mPL with low crack homogeneity. The polarity of the surfactant and the non-polarity of polytetrafluoroethylene(PTFE) are not mutually soluble,resulting in the heterogeneous PTFE distribution. The findings of this study provide guidelines for mPL fabrication.

关键词： Proton-exchange-membrane fuel cell microporous layer Crack density Crack homogeneity Polytetrafluoroethylene distribution Surfactant

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Thirty-day Outcomes of First-in-man Implantation of a Novel Transcatheter Edge-to-edge mitral Repair System in Patients With Severe mitral Regurgitation

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Cardiology Discovery 2024年第2期4卷 142-147页

作者： Kai Xu Yan Wang Shaoliang chen Xiangbin Pan ben He Ruiyan Zhang Bin Wang Junjie Zhang Zhengbin Zhu Bin Wang Da Zhu Yaling Han Department of Cardiology General Hospital of Northern Theater CommandShenyangLiaoning 110016China Department of Cardiology Xiamen Cardiovascular Hospital Xiamen UniversityXiamenFujan 361102China Department of Cardiology Nanjing First HospitalNanjingJiangsu 210006China Department of Structure Heart Disease Fuwai Yunnan Cardiovascular HospitalKunmingYunnan 650102China Department of Cardiology Shanghai Chest HospitalShanghai 200030China Department of Cardiology Rujin Hospital Shanghai Jiaotong University School of MedicineShanghai 200025China

Objectives:The aim of this multicenter,prospective,single-arm pilot study(*** number:NCT05040074)was to observe the procedural and 30-day results of the novel transcatheter mitral valve repair system,SQ-Kyrin-m Clip(Shenqi medical,Shanghai,China),in patients with severe mitral regurgitation(mR).methods:The heart team considered patients from 5 centers in China with clinically significant functional mitral regurgitation≥3+despite optimal medical therapy or degenerative mitral regurgitation≥3+with high surgical risk as candidates for transcatheter *** patients received transcatheter edge-to-edge mitral valve repair under general *** primary outcome was technical success,which included all of the following measured at the exit from the catheterization laboratory:(1)absence of procedural mortality;(2)successful access,delivery,and retrieval of the device delivery system;(3)successful deployment and correct positioning of the frst intended device;and(4)no emergency surgery or reintervention related to the device or access *** secondary outcomes included all-cause mortality,serious adverse events,device success,and procedural success 30 d after the ***:From June 2021 to December 2021,18 patients were enrolled in this study with age(75.7±7.4)*** patients had mR 4+,while 3 had mR 3+.Technical success was achieved in all patients,including 6 degenerative mitral regurgitation and 12 functional mitral regurgitation *** was no all-cause mortality at 30 *** patient had single leaflet device attachment within 30 d,which was regarded as a serious adverse event,and the patient was successfully treated with reintervention by implanting another *** patient's transmitral gradient was 6 mmHg(>5 mmHg),with an effective orifice area of 2.57 cm?after the *** patients had device success and procedural success at 30 d *** patients had mR 1+,3 had mR 2+,and only 1 pati

关键词： Heart failure mitral regurgitation Transcatheter mitral valve repair Transcatheter edge-to-edge repair

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Link between mutations in ACVRL1 and PLA2G4A genes and chronic intestinal ulcers:A case report and review of literature

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 932-943页

作者： Yong-Jing Tang Jian Zhang Jie Wang Ren-Dong Tian Wei-Wei Zhong ben-Sheng Yao Bing-Yu Hou Ying-Hua chen Wei He Yi-Huai He Department of Infectious Diseases The Affiliated Hospital of Zunyi Medical UniversityZunyi 563000Guizhou ProvinceChina Department of Gastroenterology Dafang County People's HospitalBijie 551600Guizhou ProvinceChina Department of Internal medicine Puchang BranchMedical CommunitySuiyang County People's HospitalZunyi 563300Guizhou ProvinceChina Department of Infectious Diseases Jingmen Central HospitalJingmen 448000Hubei ProvinceChina Department of Infectious Diseases Dafang County People's HospitalBijie 551600Guizhou ProvinceChina

BACKGROUND Genetic factors of chronic intestinal ulcers are increasingly garnering *** present a case of chronic intestinal ulcers and bleeding associated with mu-tations of the activin A receptor type II-like 1(ACVRL1)and phospholipase A2 group IVA(PLA2G4A)genes and review the available relevant *** SUmmARY A 20-year-old man was admitted to our center with a 6-year history of recurrent abdominal pain,diarrhea,and dark *** the onset 6 years ago,the patient had received treatment at a local hospital for abdominal pain persisting for 7 d,under the diagnosis of diffuse peritonitis,acute gangrenous appendicitis with perforation,adhesive intestinal obstruction,and pelvic *** surgical treat-ment included exploratory laparotomy,appendectomy,intestinal adhesiolysis,and pelvic abscess *** patient’s condition improved and he was ***,the recurrent episodes of abdominal pain and passage of black stools started again one year after *** the basis of these features and results of subsequent colonoscopy,the clinical diagnosis was established as in-flammatory bowel disease(IBD).Accordingly,aminosalicylic acid,immunotherapy,and related symptomatic treatment were administered,but the symptoms of the patient did not improve *** investigations revealed mutations in the ACVRL1 and PLA2G4A ***1 and PLA2G4A are involved in angiogenesis and coagulation,*** suggests that the chronic intestinal ulcers and bleeding in this case may be linked to mutations in the ACVRL1 and PLA2G4A *** Kangfuxin liquid was administered to promote healing of the intestinal mucosa and effectively manage clinical *** mutations in the ACVRL1 and PLA2G4A genes may be one of the causes of chronic intestinal ulcers and bleeding in *** administered Kangfuxin liquid may have therapeutic potential.

关键词： Intestinal ulcers Crohn’s disease Ulcerative colitis Activin A receptor type II-like 1 Phospholipase A2 group 4A Case report

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Analytical evaluation of steady-state solute distribution in through- diffusion and membrane behavior test under non-perfectly flushing boundary conditions

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Journal of Rock mechanics and Geotechnical Engineering 2024年第1期16卷 258-267页

作者： Guannian chen Yuchao Li Kristin mSample-Lord Shan Tong School of Civil&Environmental Engineering and Geography Science Ningbo UniversityNingbo315211China mOE Key Laboratory of Soft Soils and Geoenvironmental Engineering College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou310058China Ningbo ZCONE High-tech Company Limited Ningbo315000China Department of Civil and Environmental Engineering Villanova UniversityVillanovaPAUSA

The through-diffusion and membrane behavior testing procedure using a closed-system apparatus has been widely used for concurrent measurement of diffusion and membrane efficiency coefficients of low-permeability clay-based barrier ***,the common assumption of perfectly flushing conditions at the specimen boundaries could induce errors in analyses of the diffusion coefficients and membrane *** this study,an innovative pseudo three-dimensional(3D)analytical method was proposed to evaluate solute distribution along the boundary surfaces of the soil-porous disks system,considering the non-perfectly flushing *** results were consistent with numerical models under two scenarios considering different inflow/outflow *** proposed model has been demonstrated to be an accurate and reliable method to estimate solute distributions along the *** calculated membrane efficiency coefficient and diffusion coefficient based on the proposed analytical method are more accurate,resulting in up to 50%less relative error than the traditional approach that adopts the arithmetic mean value of the influent and effluent *** retar-dation factor of the clay specimen also can be calculated with a revised cumulative mass ***,the simulated transient solute transport matched with experimental data from a multi-stage through-diffusion and membrane behavior test,validating the accuracy of the proposed method.

关键词： Diffusion testing membrane behavior Coupled transport Clay barrier Transport modeling

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碱激发矿渣混凝土密实性超声无损检测法及其影响因素

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材料导报 2024年第11期38卷 166-172页

作者：李静张灵王昊陈犇陈东彬黄莹陈正广西大学土木建筑工程学院工程防灾与结构安全教育部重点实验室南宁530004

研究了碱激发矿渣混凝土水胶比、模数、碱当量及粗骨料含量对其抗压强度、超声波速的影响,并通过分析混凝土配合比参数与密度、弹性模量、孔隙率之间的关系来揭示超声波速的变化机理。结果表明:不同配合比参数的碱激发矿渣混凝土超声波... 详细信息

研究了碱激发矿渣混凝土水胶比、模数、碱当量及粗骨料含量对其抗压强度、超声波速的影响,并通过分析混凝土配合比参数与密度、弹性模量、孔隙率之间的关系来揭示超声波速的变化机理。结果表明:不同配合比参数的碱激发矿渣混凝土超声波速与弹性模量成正比,与密度、孔隙率成反比,在超声无损检测过程中可将碱激发矿渣混凝土近似作为均质性实体材料进行建模计算,发现其超声波速与抗压强度呈线性关系。基于理论分析与试验结果建立了碱激发矿渣混凝土的密实性计算模型,可以为检测碱激发矿渣混凝土密实性作参考。

关键词：碱激发矿渣混凝土抗压强度超声波速无损检测密实性

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Neural networks-based iterative learning control consensus for periodically time-varying multi-agent systems

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Science China(Technological Sciences) 2024年第2期67卷 464-474页

作者： chen JiaXi LI Junmin chen WeiSheng GAO WeiFeng School of mathematics and Statistics Xidian UniversityXi'an 710071China School of Aerospace Science and Technology Xidian UniversityXi'an 710071China

In this paper,the problem of adaptive iterative learning based consensus control for periodically time-varying multi-agent systems is studied,in which the dynamics of each follower are driven by nonlinearly parameterized terms with periodic *** networks and Fourier base expansions are introduced to describe the periodically time-varying dynamic *** this basis,an adaptive learning parameter with a positively convergent series term is constructed,and a distributed control protocol based on local signals between agents is designed to ensure accurate consensus of the closed-loop ***,consensus algorithm is generalized to solve the formation control ***,simulation experiments are implemented through mATLAB to demonstrate the effectiveness of the method used.

关键词： multi-agent systems adaptive iterative learning control nonlinearly parameterized dynamics Fourier series expansion neural networks

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Integrating phosphorus management and cropping technology for sustainable maize production

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Journal of Integrative Agriculture 2024年第4期23卷 1369-1380页

作者： Haiqing Gong Yue Xiang Jiechen Wu Laichao Luo Xiaohui chen Xiaoqiang Jiao chen chen State Key Laboratory of Nutrient Use and management College of Resources and Environmental SciencesCollege of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China Department of Sustainable Development Environmental Science and Engineering(SEED)KTH Royal Institute of TechnologyStockholm SE-10044Sweden Anhui Province Key Lab of Farmland Ecological Conservation and Pollution Prevention School of Resources and EnvironmentAnhui Agricultural UniversityHefei 230036China ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering National Observations and Research Station for Wetland Ecosystems of the Yangtze EstuaryInstitute of Biodiversity Science and Institute of Eco-ChongmingCollege of Life SciencesFudan UniversityShanghai 200438China

Achieving high maize yields and efficient phosphorus(P)use with limited environmental impacts is one of the greatest challenges in sustainable maize *** plant density is considered an effective approach for achieving high maize ***,the low mobility of P in soils and the scarcity of natural P resources have hindered the development of methods that can simultaneously optimize P use and mitigate the P-related environmental footprint at high plant *** this study,meta-analysis and substance flow analysis were conducted to evaluate the effects of different types of mineral P fertilizer on maize yield at varying plant densities and assess the flow of P from rock phosphate mining to P fertilizer use for maize production in China.A significantly higher yield was obtained at higher plant densities than at lower plant *** application of single superphosphate,triple super-phosphate,and calcium magnesium phosphate at high plant densities resulted in higher yields and a smaller environmental footprint than the application of diammonium phosphate and monoammonium *** scenario analyses suggest that combining the optimal P type and application rate with a high plant density could increase maize yield by 22%.Further,the P resource use efficiency throughout the P supply chain increased by 39%,whereas the P-related environmental footprint decreased by 33%.Thus,simultaneously optimizing the P type and application rate at high plant densities achieved multiple objectives during maize production,indicating that combining P management with cropping techniques is a practical approach to sustainable maize *** findings offer strategic,synergistic options for achieving sustainable agricultural development.

关键词： maize plant density mineral phosphorus fertilizer meta-analysis substance flow analysis

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