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Erosion and covered zones altered by surface coverage effects on soil nitrogen and carbon loss from an agricultural slope under laboratorysimulated rainfall events

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International Soil and Water Conservation Research 2022年第3期10卷 382-392页

作者： Linhua wang haw Yen Chi-hua Huang Yafeng wang Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems South China Botanical GardenChinese Academy of SciencesGuangzhou510650China USDA-ARS National Soil Erosion Research Laboratory West LafayetteIN47907-2077USA Blackland Research and Extension Center Texas A&M Agrilife ResearchTexas A&M UniversityTexas76502USA Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing100101China

Soil erosion,one of the most serious environmental concerns,might remove topsoil and essential element from terrestrial ***,few attentions have been given to investigating how soil erosion regimes affect soil carbon and nitrogen ***,this study investigated the effects of surface coverage rates(83%,67%,50%,33%,17%and 0%)and two positions(up-and downslope)on erosion regimes and its associated soil nitrogen and carbon loss under a sequence of six rainfalls(R1-R6).These results showed that the sediment concentrations with 33%(R4)and 17%(R5)coverage downslope were significantly lower than those with coverage upslope,whereas there was no significant difference between the runoff rates of the two ***,surface coverage at different positions induced two soil erosion regimes(deposition-and transport-dominated processes).Dynamics of the DON and DIN concentrations indicated different release processes of soil nitrogen into *** DON contributed to a substantial amount of soil nitrogen loss,which accounted approximately 81%of the organic *** SBOC is significantly correlated with sediment-enriched clay particles from the deposition-dominated processes and is higher than that from the transport-dominated *** DOC is significantly correlated with Rr for transport-dominated *** results illustrated the critical role of erosion regimes in soil organic carbon loss in dissolved or sediment-bound *** is concluded that erosion/covered zones altered by surface coverage could produce transport-and deposition-dominated erosion regimes and consequently affect soil carbon and nitrogen *** addition,these results demonstrated that surface coverage pattern may efficiently control soil erosion and soil carbon and nitrogen loss.

关键词： Erosion regimes Carbon and nitrogen loss Surface coverage Coverage position

Wafer-Scale Vertical 1D GaN Nanorods/2D MoS₂/PEDOT:PSS for Piezophototronic Effect-Enhanced Self-Powered Flexible Photodetectors

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NANO-MICRO LETTERS 2025年第1期17卷 1-15页

作者： Tang, Xin Jiang, Hongsheng Lin, Zhengliang wang, Xuan wang, Wenliang Li, Guoqiang South China Univ Technol State Key Lab Luminescent Mat & Devices Guangzhou 510640 Peoples R China South China Univ Technol Sch Mat Sci & Engn Dept Elect Mat Guangzhou 510640 Peoples R China

Vertical 1D GaN nanorod arrays/2D MoS2/PEDOT:PSS heterostructures in wafer scale have been fabricated for flexible photodetection ***-powered flexible photodetector at compressive strain reveals a significantly enhanced photoresponse with a responsivity of 2.47 A W-1 and response times of 40/45 mu s, which are superior to the state-of-the-art flexible *** work not only provides a valuable strategy for the design and construction of tunable van der Waals heterostructures, but also opens a new opportunity for flexible sensors. van der Waals (vdW) heterostructures constructed by low-dimensional (0D, 1D, and 2D) materials are emerging as one of the most appealing systems in next-generation flexible photodetection. Currently, hand-stacked vdW-type photodetectors are not compatible with large-area-array fabrication and show unimpressive performance in self-powered mode. Herein, vertical 1D GaN nanorods arrays (NRAs)/2D MoS2/PEDOT:PSS in wafer scale have been proposed for self-powered flexible photodetectors arrays firstly. The as-integrated device without external bias under weak UV illumination exhibits a competitive responsivity of 1.47 A W-1 and a high detectivity of 1.2 x 1011 Jones, as well as a fast response speed of 54/71 mu s, thanks to the strong light absorption of GaN NRAs and the efficient photogenerated carrier separation in type-II heterojunction. Notably, the strain-tunable photodetection performances of device have been demonstrated. Impressively, the device at - 0.78% strain and zero bias reveals a significantly enhanced photoresponse with a responsivity of 2.47 A W-1, a detectivity of 2.6 x 1011 Jones, and response times of 40/45 mu s, which are superior to the state-of-the-art self-powered flexible photodetectors. This work presents a valuable avenue to prepare tunable vdWs heterostructures for self-powered flexible photodetection, which performs well in flexible sensors.

关键词： Vertical nanorod arrays van der Waals heterostructure Piezophototronic effect Self-powered photodetection Flexible sensors

Occurrence, spatial distribution and ecological risks of antibiotics in soil in urban agglomeration

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Journal of Environmental Sciences 2023年第3期125卷 678-690页

作者： Min Li Lei Yang haw Yen Fangkai Zhao Xinmiao wang Tianhui Zhou Qingyu Feng Liding Chen State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China School of Forestry and Wildlife Sciences Auburn UniversityTexas 36849USA School of Ecology and Environmental Science Yunnan UniversityKunming 650500China

Antibiotics in soil environment are regarded as emerging pollutants and have introduced increasing risks to soil ecosystem and human health in rapid urbanization areas. Identifying the occurrence and spatial variability of antibiotics in soils is an urgent issue in sustaining soil security. In this study, antibiotics in soils were investigated and analyzed in BeijingTianjin-Hebei urban agglomeration. The occurrence, spatial distribution, and related affecting factors of antibiotics in soils were identified and ecological risks of antibiotics in soil environment were assessed. Results showed that(1) The mean concentration of soil antibiotics in Beijing-Tianjin-Hebei urban agglomeration was 21.79 μg/kg. Land use substantially affected the occurrence and concentration of antibiotics in soils. Concentrations of antibiotics in cropland and orchard soils were 2-3 times higher than the other land use types.(2)The concentrations of antibiotics in soils in Beijing-Tianjin-Hebei urban agglomeration presented a spatial pattern of high values in southeast, and low values in northwest. Spatial variability of antibiotics in soils was closely related to the application of organic fertilizer and wastewater irrigation as well as topographical features. Furthermore, soil properties and land management policy had substantial influences on soil antibiotics, and soil heavy metals may aggravate the accumulation of antibiotics in soils.(3) Ecological risks assessment of antibiotics in soils demonstrated that erythromycin(ERY), sulfamethoxazole(SMX), and doxycycline(DOX) may introduce high risks to soil ecosystem health, and more attention should be paid to the areas with intensive human activities that had potential high risk to soil ecosystem health. This study suggests that scientific land and soil management should be considered to prevent soil antibiotic pollution and sustain soil security in urban agglomeration.

关键词： Antibiotics Urban agglomeration Land use Land management Urban-rural environmental gradient

Applying model simulation and photochemical indicators to evaluate ozone sensitivity in southern Taiwan

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Journal of Environmental Sciences 2011年第5期23卷 790-797页

作者： Yen-Ping Peng Kang-Shin Chen Hsin-Kai wang Chia-Hsiang Lai Ming-Hsun Lin Cheng-haw Lee Graduate Institute of Environmental Engineering "National" Taiwan University Institute of Environmental Engineering National Sun Yat-Sen University Institute of Environmental Engineering National Sun Yat-Sen University Department of Health Safety and Environmental Engineering Central Taiwan University of Science and Technology Department of Resources Engineering National Cheng-Kung University

Ozone sensitivity was investigated using CAMx simulations and photochemical indicator ratios at three sites （Pingtung City, Chao-Chou Town, and Kenting Town） in Pingtung County in southern Taiwan during 2003 and 2004. The CAMx simulations compared fairly well with the hourly concentrations of ozone. Simulation results also showed that Pingtung City was mainly a volatile organic compounds （VOC）-sensitive regime, while Chao-Chou Town was either a VOC-sensitive or a NOx-sensitive regime, depending on the seasons. Measurements of three photochemical indicators （H202, HNO3, and NOy） were conducted, and simulated three transition ranges of H202/HNO3 （0.5-0.8）, O3/HNO3 （10.3-16.2） and O3/NOy （5.7-10.8） were adopted to assess the ozone sensitive regime at the three sites. The results indicated that the three transition ranges yield consistent results with CAMx simulations at most times at Pingtung City. However, both VOC-sensitive and NOx-sensitive regimes were important at the rural site Chao-Chou Town. Kenting Town, a touring site at the southern end of Taiwan, was predominated by a NOx-sensitive regime in four seasons.

关键词： photochemical indicator ozone sensitivity volative organic compounds NOx CAMx

Alkali and alkaline ions co-substitution of P2 sodium layered oxides for sodium ion batteries

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Chinese Journal of Structural Chemistry 2023年第5期42卷 13-21页

作者： Yuncai Chen Maolin Yang Liangtao Yang Ziwei Chen Huiyun Li haw Jiunn Woo Shang-Sen Chi Yinguo Xiao Jun wang Chaoyang wang Yonghong Deng Key University Laboratory of Highly Efficient Utilization of Solar Energy and Sustainable Development of Guangdong Department of Materials Science&EngineeringSchool of Innovation and EntrepreneurshipSouthern University of Science and TechnologyShenzhen518055China Centre for Ionics University Malaya Department of PhysicsFaculty of ScienceUniversity of MalayaKuala Lumpur50603Malaysia School of Advanced Materials Peking UniversityShenzhen Graduate SchoolShenzhen518055China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen518055China Research Institute of Materials Science South China University of TechnologyGuangzhou510640China

Alkali and alkaline ion substitutions enhance the electrochemical properties of P2 sodium layered oxide,while the effect on electrochemical property enhancement of alkali and alkaline ions co-substitution is still *** this work,the structural and electrochemical properties of the Li alkali and Mg alkaline ions co-substituted P2 layered oxide Na_(0.67)(Li_(0.5)Mg_(0.5))_(0.1)(Ni_(0.33)Mn_(0.67))_(0.9)O_(2)are investigated in *** to the pristine and single-ion substituted materials,the co-substituted material shows an enhanced cycling performance with a reversible ca-pacity of 127 mAh/g and a capacity retention of 75%over 100 cycles at *** intermittent titration technique(GITT)and cyclic voltammetry(CV)results show that the Li and Mg synergistically improve the ion ***,the structure stability is also improved by the Li and Mg co-substitution that is clarified by operando X-ray diffraction(XRD)*** results explain the origin of the enhanced electrochemical properties of the Li/Mg co-substituted P2 layered oxides for sodium ion batteries.

关键词： Sodium ions batteries Sodium layered oxides Alkali and alkaline elements co-substitution Neutron diffraction Structural evolution

The correlation between plasma cytokine levels in jaundice-free children with biliary atresia

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World Journal of Pediatrics 2015年第4期11卷 352-357页

作者： Zhi-Hong Jian Li-Ching wang Chieh-Chung Lin Jiaan-der wang Division of Pediatric Gastroenterology Department of PediatricsTaichung Veterans General HospitalTaichung City 40705TaiwanChina Department of Public Health and Institute of Public Health Chung Shan Medical UniversityTaichung City 40201TaiwanChina School of Medicine China Medical UniversityTaichungTaiwanChina

Background:T helper(Th)cell cytokines modulate inflammation and play a role in biliary atresia(BA).The aim of the study is a cross-sectional assessment of the levels of Th cytokines in the jaundice-free post Kasai procedure ***:There were 40 jaundice-free patients with BA and 28 normal controls *** were divided into 3 groups,including normal liver function,impaired liver function,and portal *** concentration of Th1[interferon-γ(INF-γ),interleukin(IL)-2],Th2(IL-4,IL-10),Th3[transforming growth factor-β1(TGF-β1)],Th17(IL-17)cytokines,and stromal cell-derived factor-1α(SDF-1α)were ***:The IFN-γ level was significantly higher in the BA patients with impaired liver function and portal hypertension than controls(P<0.0001 andP<0.0001,respectively).There was a signifi cantly increase of TGF-β1 in all BA groups compared with controls(P=0.003).The reduction of SDF-1αexpression was found in BA groups(P<0.0001).IL-10 levels significantly correlated with aspartate aminotransferase to platelet ratio index(r=0.496,P=0.001).For the cytokine correlations,there were no correlations of Th1,Th2 and Th17 cytokine with the other measured cytokines,but TGF-β1 was negatively correlated with SDF-1αlevels(r=-0.327,P=0.039).Conclusions:IFN-γand IL-10 are likely to be involved in the disease progression in ***,TGF-β1 is found to be a suppression marker associated with SDF-1αlevels and reduced production of TGF-β1 may be associated with the disease progression.

关键词： biliary atresia gastroenterology immunology pediatric disease

A generic high-throughput microstructure classification and quantification method for regular SEM images of complex steel microstructures combining EBSD labeling and deep learning

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Journal of Materials Science & Technology 2021年第34期93卷 191-204页

作者： Chunguang Shen Chenchong wang Minghao Huang Ning Xu Sybrand van der Zwaag Wei Xu State key laboratory of rolling and automation Northeastern UniversityShenyangLiaoning 110819China Novel Aerospace Materials Group Faculty of Aerospace EngineeringDelft University of Technology2629 HS Delftthe Netherlands

We present an electron backscattered diffraction(EBSD)-trained deep learning(DL)method integrating traditional material characterization informatics and artificial intelligence for a more accurate classification and quantification of complex microstructures using only regular scanning electron microscope(SEM)*** this method,EBSD analysis is applied to produce accurate ground truth data for guiding the DL model *** U-Net architecture is used to establish the correlation between SEM input images and EBSD ground truth data using only small experimental *** proposed method is successfully applied to two engineering steels with complex microstructures,i.e.,a dual-phase(DP)steel and a quenching and partitioning(Q&P)steel,to segment different phases and quantify phase content and grain ***,once properly trained the method can also produce quasi-EBSD maps by inputting regular SEM *** good generality of the trained models is demonstrated by using DP and Q&P steels not associated with the model ***,the method is applied to SEM images with various states,i.e.,different imaging modes,image qualities and magnifications,demonstrating its good robustness and strong application ***,the visualization of feature maps during the segmenting process is utilised to explain the mechanism of this method’s good performance.

关键词： Microstructure quantification Deep learning Electron backscatter diffraction Small sample problem

Minimal Lagrangian submanifolds of the complex hyperquadric

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Science China Mathematics 2020年第8期63卷 1441-1462页

作者： Haizhong Li Hui Ma Joeri Van der Veken Luc Vrancken Xianfeng wang Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China Department of Mathematics KU LeuvenLeuven 3001Belgium Institut des Sciences et Techniques de Valenciennes Universite Polytechnique Hauts-de-FranceCampus du Mont HouyValenciennes 59313France School of Mathematical Sciences and LPMC Nankai UniversityTianjin 300071China Mathematical Sciences Institute Australian National UniversityCanberraACT 2601Australia

We introduce a structural approach to study Lagrangian submanifolds of the complex hyperquadric in arbitrary dimension by using its family of non-integrable almost product *** particular,we define local angle functions encoding the geometry of the Lagrangian submanifold at *** prove that these functions are constant in the special case that the Lagrangian immersion is the Gauss map of an isoparametric hypersurface of a sphere and give the relation with the constant principal curvatures of the *** also use our techniques to classify all minimal Lagrangian submanifolds of the complex hyperquadric which have constant sectional curvatures and all minimal Lagrangian submanifolds for which all local angle functions,respectively all but one,coincide.

关键词： minimal Lagrangian submanifolds the complex hyperquadric constant sectional curvature Gauss map isoparametric hypersurface

Sintering of WC-Co powder with nanocrystalline WC by spark plasma sintering

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Rare Metals 2006年第3期25卷 246-252页

作者： wang Xingqing XIE Yingfang GUO Hailiang O.Van der Biest J.Vleugels School of Materials Science and Engineering Shanghai University Shanghai 200072 China Materials Engineering Faculty of Engineering Katholikeke Universiteit Leuven Leuven 3000 Belgium

A 92WC-8Co powder mixture with 33 nm WC grains was prepared by strengthening ball milling and was then sintered by spark plasma sintering （SPS） at 1000-1200℃ for 5-18 rain under 10-25 kN, respectively. Movement of the position of low punch shown shrinkage of the sintered body began above 800℃. The shrinkage slowly rose as the temperature rose from 800 to 1000℃ and then quickly rose at above 1000℃ and then gradually rose at above 1150℃. The densities of the samples increased with an increase in sintering temperature, rapidly below 1100℃, and then gradually above 1100℃. WC grains grow gradually with increasing sintering temperature. The powder was sintered to near full density at 1100℃ for 5 rain under 10 kN. The best result of the sample with 275 nm WC grains and no pores was obtained at 1150℃ under 10 kN for 5 rain. The research found the graphite die had a function of carburization, which could compensate the sintered body for the lack of carbon, and had the normal microstructure.

关键词： nanocrystalline cemented carbide spark plasma sintering low temperature sintering strengthening ball milling