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The multiple roles of crop structural change in productivity,nutrition and environment in China:A decomposition analysis

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Journal of Integrative Agriculture 2024年第5期23卷 1763-1773页

作者： Xiangyang Zhang Yumei Zhang Shenggen Fan College of Economics and Management China Agricultural UniversityBejing 100083China Academy of Global Food Economics and Policy China Agricultural UniversityBejing 100083China

China's crop structure has undergone significant changes in the last two decades since 2000,with an increase in the share of cereals,vegetables,and fruit,squeezing out other *** a result,land productivity,nutrient supply,and carbon emissions have *** to reallocate limited farmland among crops to achieve the multiple goals of agrifood systems becomes an important *** study explores the sources of land productivity and nutrition supply growth and carbon emissions reduction,and identifies the multiple roles of crop structural change from 2003 to 2020 based on a decomposition *** results reveal that the growth within crops is still the primary driver in land productivity and nutrition supply and the reduction in carbon ***,structural change also plays various roles at different *** 2003 to 2010,crop structural change increased the total calorie supply but lowered land productivity and contributed at least 70%of the total growth of carbon *** crop structure was relatively stable,and their effects were modest from 2010 to *** 2015 to 2020,the crop structural change began to play a greater role and generate synergistic effects in improving land productivity,micronutrient supply,and reducing carbon emissions,contributing to approximately a quarter of the growth of land productivity and 30%of total carbon emissions *** results suggest that strategies for crop structural change should comprehensively consider its multiple impacts,aiming to achieve co-benefits while minimizing trade-offs.

关键词： crop structural change land productivity nutrition carbon emissions

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Mold breakout prediction based on computer vision and machine learning

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Journal of Iron and Steel Research International 2024年第8期31卷 1947-1959页

作者： Yan-yu Wang Qi-can Wang Yong-chang Zhang Yong-hui Cheng Man Yao Xu-dong Wang School of Materials science and Engineering Dalian University of TechnologyDalian 116024LiaoningChina Key Laboratory of Solidification Control and Digital Preparation Technology Dalian University of TechnologyDalian 116024LiaoningChina

Breakout is the most serious production accident in continuous casting and must be detected and predicted by stable and reliable *** sticking region,which forms on the local copper plate and expanded into a"V"shape,is the typical precursor of ***,computer vision technology was exploited to visualize the temperature change rate of the copper plate based on the temperature signals from thermocouples;then,the static and dynamic features of the abnormal sticking region were ***,logistic regression and Adaboost models were used to study and identify these features,resulting in the development of a mold breakout prediction model based on computer vision and machine *** test results demonstrate that the proposed model can effectively distinguish anomalous temperature patterns and considerably reduce false alarms without any missing *** a result,the proposed method could offer valuable insights into the realm of abnormality detection and prediction during continuous casting process.

关键词： Abnormality detection Image processing Adaboost Logistic regression Continuous casting

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Degree of shade tolerance shapes seasonality of chlorophyll, nitrogen and phosphorus levels of trees and herbs in a temperate deciduous forest

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Journal of Forestry Research 2024年第4期35卷 60-72页

作者： Jiajia Zeng Fan Liu Yuan Zhu Jiayi Li Ying Ruan Xiankui Quan Chuankuan Wang Xingchang Wang Aulin College Northeast Forestry UniversityHarbin 150040People’s Republic of China Center for Ecological Research Northeast Forestry UniversityHarbin 150040People’s Republic of China Key Laboratory of Agricultural Water Resources Center for Agricultural Resources ResearchInstitute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021People’s Republic of China Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016People’s Republic of China Key Laboratory of Sustainable Forest Ecosystem Management Ministry of EducationNortheast Forestry UniversityHarbin 150040People’s Republic of China

Forest productivity is closely linked to seasonal variations and vertical differentiation in leaf ***,leaf structural and chemical traits variation among co-existing species,and plant functional types within the canopy are poorly *** this study,the seasonality of leaf chlorophyll,nitrogen(N),and phosphorus(P)were quantified vertically along the canopy of four major tree species and two types of herbs in a temperate deciduous *** role of shade tolerance in shaping the seasonal variation and vertical differentiation was *** the entire season,chlorophyll content showed a distinct asymmetric unimodal pattern for all species,with greater chlorophyll levels in autumn than in spring,and the timing of peak chlorophyll per leaf area gradually decreased as shade tolerance *** a:b ratios gradually decreased with increasing shade *** N and P contents sharply declined during leaf expansion,remained steady in the mature stage and decreased again during leaf *** the seasons,the lower canopy layer had significantly higher chlorophyll per leaf mass but not chlorophyll per leaf area than the upper canopy layer regardless of degree of shade ***,N and P per leaf area of intermediate shade-tolerant and fully shade-tolerant tree species were significantly higher in the upper canopy than in the *** variations in N:P ratios suggest changes in N or P *** findings indicate that shade tolerance is a key feature shaping inter-specific differences in leaf chlorophyll,N,and P contents as well as their seasonality in temperate deciduous forests,which have significant implications for modeling leaf photosynthesis and ecosystem production.

关键词： Leaf traits Leaf nutrients Seasonal variations Chlorophyll Nitrogen Phosphorus Shade tolerance Canopy layers

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Modulating low-frequency tribocatalytic performance through defects in uni-doped and bi-doped SrTiO_(3)

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Journal of Advanced Ceramics 2024年第8期13卷 1153-1163页

作者： Yjing Xu Yingzhi Meng Xu Xiang Qing Tang Hongfang Zhang Lajun Liu Ju Gao Bo Xu Renhong Liang Longlong Shu Yanmin Jia Wanping Chen School of Physical science and Technology Suzhou University of Science and TechnologySuzhou 215009China College of Materials science and Engineering Guilin University of TechnologyGuilin 541004China Key Laboratory of Advanced Electrode Materials for Novel Solar Cells for Petroleum and Chemical Industry of China Suzhou University of Science and TechnologySuzhou 215009China School of science and Key Laboratory of Biomedical Functional Materials China Pharmaceutical UniversityNanjing 211198China School of Physics and Materials science Guangzhou UniversityGuangzhou 510006China School of Physics and Materials science Nanchang UniversityNanchang 330031China School of Physics and Information Technology Shaanxi Normal UniversityXi'an 710062China School of Physics and Technology Wuhan UniversityWuhan 430072China

Triboelectrification,a process that transforms mechanical energy into electrical energy through friction,holds promise for eco-friendly wastewater *** study delves into the enhancement of tribocatalytic dye degradation using SrTiO_(3),a material notable for its non-piezoelectric and centrosymmetric *** synthesis of uni-and bi-doped SrTiOs particles,achieved through a solid-state reaction at 100℃,results in a high-purity cubic perovskite *** with rhodium(Rh)and carbon(C)causes crystal lattice contraction,internal stress,and significant oxygen *** changes notably improve tribocatalytic efficiency under solar irradiation,with Rh-doped SrTiO_(3) demonstrating an impressive degradation rate of approximately 88% for Rhodamine B(RhB),along with reaction rate constants near 0.9 h^(-1) at 554 nm and a noticeable *** study highlights that defects introduced by doping are integral to this process,boosting catalytic activity through energy state modification and enhancing surface redox radical ***,these defects are instrumental in generating a flexoelectric field,which markedly influences the separation of electron-hole pairs under solar *** findings illuminate the complex interplay between material composition,defect states,and environmental conditions,paving the way for advanced strategies in environmental remediation through optimized tribocatalytic activity.

关键词： tribocatalysis SrTiO_(3)(STO) doping-induced defects blueshift flexoelectric field

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Material-SAM:Adapting SAM for Material XCT

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Computers, Materials & Continua 2024年第3期78卷 3703-3720页

作者： Xuelong Wu Junsheng Wang Zhongyao Li Yisheng Miao Chengpeng Xue Yuling Lang Decai Kong Xiaoying Ma Haibao Qiao School of Materials science and Engineering Beijing Institute of TechnologyBeijing100081China Senior Engineer at the Simulation Center Citic Dicastal Co.Ltd.Qinhuangdao066010China

X-ray Computed Tomography(XCT)enables non-destructive acquisition of the internal structure of materials,and image segmentation plays a crucial role in analyzing material XCT *** paper proposes an image segmentation method based on the Segment Anything model(SAM).We constructed a dataset of carbide in nickel-based single crystal superalloys XCT images and preprocessed the images using median filtering,histogram equalization,and gamma ***,SAM was fine-tuned to adapt to the task of material XCT image segmentation,resulting in *** compared the performance of threshold segmentation,SAM,U-Net model,and *** method achieved 88.45%Class Pixel Accuracy(CPA)and 88.77%Dice Similarity Coefficient(DSC)on the test set,outperforming SAM by 5.25%and 8.81%,respectively,and achieving the highest ***-SAM demonstrated lower input requirements compared to SAM,as it only required three reference points for completing the segmentation task,which is one-fifth of the requirement of ***-SAM exhibited promising results,highlighting its potential as a novel method for material XCT image segmentation.

关键词： Segment Anything model X-ray computed tomography U-Net Ni-based superalloys foundation models

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Online estimation and characteristic analysis of double nugget diameters during aluminum/steel resistance spot welding process

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Journal of Iron and Steel Research International 2024年第8期31卷 2053-2067页

作者： Kang Zhou Wen-xiao Yu Bao-kai Ren Gang Wang School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

Online estimation of the double nugget diameters was performed by means of a back propagation neural *** double nugget diameters were obtained using actual welding experiment and numerical simulation,according to different characteristics of aluminum nugget and steel *** input of the neural network was some key characteristic parameters extracted from dynamic power signal,which were peak point,knee point and their variation rate over time,as well as heat energy delivered into the welding *** architecture of the neural network was confirmed by confirming the number of neurons in hidden layer through a series of *** key parameters of the neural network were obtained by means of training 81 arrays of data ***,the neural network was used to test the remaining 20 arrays of verifying data set,and the results showed that both of the mean errors for the two nugget diameters were below 3%.In addition,corresponding analyses showed that the accuracy of two nugget diameters was higher than that of tensile-shear strength.

关键词： Resistance spot welding Aluminum Steel Double nugget Dynamic power signal.Neural network

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Polystyrene microplastics disrupted physical barriers, microbiota composition and immune responses in the cecum of developmental Japanese quails

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Journal of Environmental sciences 2024年第10期144卷 225-235页

作者： Lingyang Jing Yuxin Zhang Qingyu Zhang Hongfeng Zhao College of Life sciences Shaanxi Normal UniversityXi’an 710119China

Microplastics,a new type of emerging pollutant,is ubiquitous in terrestrial and water *** have become a growing concern due to their impacts on the environment,animal,and human *** also suffer from microplastics *** this study,we examined the toxic effects of polystyrene microplastics(PS-MPs)exposure on physical barrier,microbial community,and immune function in the cecum of a model bird species—Japanese quail(Coturnix japonica).The one-week-old birds were fed on environmentally relevant concentrations of 20μg/kg,400μg/kg,and 8 mg/kg PS-MPs in the diet for 5 *** results showed that microplastics could cause microstructural damages characterized by lamina propria damage and epithelial cell vacuolation and ultrastructural injuries including microvilli breakage and disarrangement aswell asmitochondrial vacuolation in the cecum of *** particular,blurry tight junctions,wider desmosomes spacing,and gene expression alteration indicated cecal tight junction ***,mucous layer breakdown andmucin decrease indicated that chemical barrier was disturbed by ***-MPs also changed cecal microbial *** addition,structural deformation of cecal tonsils and increasing proinflammatory cytokines suggested cecal immune disorder and inflammation responses by PS-MPs *** results suggested that microplastics negatively affected digestive system and might pose great health risks to terrestrial birds.

关键词： Microplastics Gut barrier Histology Inflammation Immunity Oxidative stress

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Linear mathematical model for the unique solution of 3D ptychographic iterative engine

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Chinese Optics Letters 2024年第5期22卷 1-7页

作者：吴丽青齐乃杰昌成成陶华何小亮刘诚朱健强 Key Laboratory of High Power Laser and Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China national Laboratory on High Power Laser and Physics China Academy of Engineering PhysicsChinese Academy of SciencesShanghai 201800China University of Chinese Academy of sciences Beijing 100049China

Diffraction intensities of the 3D ptychographic iterative engine(3PIE)were written as a set of linear equations of the selfcorrelations of Fourier components of all sample slices,and an effective computing method was developed to solve these linear equations for the transmission functions of all sample slices *** both theoretical analysis and numerical simulations,this study revealed the underlying physics and mathematics of 3PIE and demonstrated for the first time,to our knowledge,that 3PIE can generate mathematically unique reconstruction even with noisy data.

关键词： 3D imaging 3D ptychographic iterative engine linear equation group unique solution

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Milestone progress of the HEPS booster commissioning

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Nuclear science and Techniques 2024年第1期35卷 170-177页

作者： Yue-Mei Peng Jian-She Cao Jin-Hui Chen Hai-Yi Dong Ping He Yi Jiao Ling Kang Wen Kang Jian Li Jing-Yi Li Guo-Ping Lin Fang Liu Feng-Li Long Cai Meng Xin Qi Hua-Min Qu Yan-Feng Sui Sheng Wang Gang Xu Qiang Ye Jing Zhang Pei Zhang Wei-Min Pan Key Laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of Sciences19B Yuquan RoadShijingshan DistrictBeijing 100049China University of the Chinese Academy of sciences 19A Yuquan RoadShijingshan DistrictBeijing 100049China

The high-energy photon source(HEPS)is the first fourth-generation synchrotron light source facility in *** HEPS injector consists of a linear accelerator(Linac)and a full energy *** booster captures the electron beam from the Linac and increases its energy to the value required for the storage *** full-energy beam could be injected to the storage ring directly or after“high-energy accumulation.”On November 17,2023,the key booster parameters successfully reached their corresponding target *** milestone results were achieved based on numerous contributions,including nearly a decade of physical design,years of equipment development and installation,and months of beam *** measured at the extraction energy of 6 GeV,the averaged beam current and emittance reached 8.57 mA with 5 bunches and 30.37 nm rad with a single-bunch charge of 5.58 nC,compared with the corresponding target values of 6.6 mA and 35 nm rad,*** paper presents the physical design,equipment development,installation,and commissioning process of the HEPS booster.

关键词： High energy photon source Booster Beam commissioning

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A super sandstorm altered the abundance and composition of airborne bacteria in Beijing

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Journal of Environmental sciences 2024年第10期144卷 35-44页

作者： Fanxuan Xia Zhuo Chen Enze Tian Jinhan Mo Beijing Key Laboratory of Indoor Air Quality Evaluation and Control Department of Building ScienceTsinghua UniversityBeijing 100084China Songshan Lake Materials Laboratory Dongguan 523808China Institute of Physics Chinese Academy of SciencesBeijing 100190China College of Civil and Transportation Engineering Shenzhen UniversityShenzhen 518060China Key Laboratory of Coastal Urban Resilient Infrastructures(Shenzhen University) Ministry of EducationShenzhen 518060China Key Laboratory of Eco Planning&Green Building(Tsinghua University) Ministry of EducationBeijing 100084China

Sandstorm,which injects generous newly emerging microbes into the atmosphere covering cities,adversely affects the air quality in built ***,few studies have examined the change of airborne bacteria during severe sandstorm *** this work,we analyzed the airborne bacteria during one of the strongest sandstorms in East Asia onMarch 15th,2021,which affected large areas of China and *** characteristics of the sandstorm were compared with those of the subsequent clean and haze *** composition of the bacterial community of air samples was investigated using quantitative polymerase chain reaction(qPCR)and high-throughput sequencing *** the sandstorm,the particulate matter(PM)concentration and bacterial richnesswere extremely high(PM2.5:207μg/m3;PM10:1630μg/m3;5700 amplicon sequence variants/m3).In addition,the sandstorm brought 10 pathogenic bacterial genera to the atmosphere,posing a grave hazard to human *** the sandstorm subsided,small bioaerosols(0.65–1.1μm)with a similar bacterial community remained suspended in the atmosphere,bringing possible long-lasting health risks.

关键词： Airborne bacteria Sandstorm Bioaerosol Haze Pathogen

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