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Mapping landslide susceptibility at the Three Gorges Reservoir, China, using gradient boosting decision tree,random forest and information value models

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Journal of Mountain Science 2020年第3期17卷 670-685页

作者： CHEN Tao ZHU Li niu Rui-qing TRINDER C John PENG Ling LEI Tao Institute of Geophysics and Geomatics China University of GeosciencesWuhan 430074China Geomatics Technology and Application key Laboratory of qinghai Province Xining 810001China School of Civil and Environmental Engineering The University of New South WalesSydneyNSW 2052Australia China Institute of Geo-Environment Monitoring Beijing 100081China School of Electronical and Information Engineering Shaanxi University of Science and TechnologyXi’an 710021China

This work was to generate landslide susceptibility maps for the Three Gorges Reservoir(TGR) area, China by using different machine learning models. Three advanced machine learning methods, namely, gradient boosting decision tree(GBDT), random forest(RF) and information value(InV) models, were used, and the performances were assessed and compared. In total, 202 landslides were mapped by using a series of field surveys, aerial photographs, and reviews of historical and bibliographical data. Nine causative factors were then considered in landslide susceptibility map generation by using the GBDT, RF and InV models. All of the maps of the causative factors were resampled to a resolution of 28.5 m. Of the 486289 pixels in the area,28526 pixels were landslide pixels, and 457763 pixels were non-landslide pixels. Finally, landslide susceptibility maps were generated by using the three machine learning models, and their performances were assessed through receiver operating characteristic(ROC) curves, the sensitivity, specificity,overall accuracy(OA), and kappa coefficient(KAPPA). The results showed that the GBDT, RF and In V models in overall produced reasonable accurate landslide susceptibility maps. Among these three methods, the GBDT method outperforms the other two machine learning methods, which can provide strong technical support for producing landslide susceptibility maps in TGR.

关键词： Mapping landslide susceptibility Gradient boosting decision tree Random forest Information value model Three Gorges Reservoir

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Control core of safety management: the reasonable distribution of safety resources

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Journal of Coal Science & Engineering(China) 2009年第3期15卷 328-331页

作者： YAO qing-guo ZHANG Xue-mu College of Economic and Management Shandong University of Science and Technology Qingdao 266510 China

The distribution of resources is the basis of safety *** on thesystematic analysis of a resource distribution system affecting the level of safety,the bestdistribution proportion between safety activities and production and best resources distributionproportion among the various links of security activities are ***,itis stated that the distribution of resources law needs to be researched deeply in practicalwork to achieve optimization of safety management practice.

关键词： safety management safety resource resource distribution

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Spatial confinement of copper single atoms into covalent triazinebased frameworks for highly efficient and selective photocatalytic CO_(2)reduction

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Nano Research 2022年第9期15卷 8001-8009页

作者： Guocheng Huang qing niu Yuxin He Jinjin Tian Mingbin Gao Chaoyang Li Ning An Jinhong Bi Jiangwei Zhang Department of Environmental Science and Engineering Fuzhou UniversityFuzhou 350108China Advanced Chemical Engineering and Energy Materials Research Center China University of Petroleum(East China)Qingdao 266580China State Key Laboratory of Photocatalysis on Energy and Environment Fuzhou UniversityFuzhou 350108China National Engineering Laboratory for Methanol to Olefins Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Anhui Chuangpu Instrument Technology Co. LTD.Hefei 230088China

Converting CO_(2)into carbonaceous fuels via photocatalysis represents an appealing strategy to simultaneously alleviate the energy crisis and associated environmental problems,yet designing with high photoreduction activity catalysts remains a compelling ***,combining the merits of highly porous structure and maximum atomic efficiency,we rationally constructed covalent triazine-based frameworks(CTFs)anchoring copper single atoms(Cu-SA/CTF)photocatalysts for efficient CO_(2)*** Cu single atoms were visualized by high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM)images and coordination structure of Cu-N-C2 sites was revealed by extended X-ray absorption fine structure(EXAFS)*** as-prepared Cu-SA/CTF photocatalysts exhibited superior photocatalytic CO_(2)conversion to CH4 performance associated with a high selectivity of 98.31%.Significantly,the introduction of Cu single atoms endowed the CuSA/CTF catalysts with increased CO_(2)adsorption capacity,strengthened visible light responsive ability,and improved the photogenerated carriers separation efficiency,thus enhancing the photocatalytic *** work provides useful guidelines for designing robust visible light responsive photoreduction CO_(2)catalysts on the atomic scale.

关键词： covalent triazine-based frameworks Cu single atoms photocatalytic CO_(2)reduction visible light selectivity

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Fine mapping and characterization of the awn inhibitor B1 locus in common wheat(Triticum aestivum L.)

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The Crop Journal 2020年第4期8卷 613-622页

作者： Jianqing niu Shusong Zheng Xiaoli Shi Yaoqi Si Shuiquan Tian Yilin He Hong-qing Ling State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental BiologyThe Innovative Academy of Seed DesignChinese Academy of SciencesBeijing 100101China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China

Awns play an important role in seed dispersal and photosynthesis of *** major awn inhibitors(Hd,B1,and B2)are reported in ***,the molecular mechanism underlying awnlessness remained unknown until *** this study,we identified two F8 recombinant inbred lines(RILs)that were segregating for awn *** order to identify the causal gene for awn length in the heterozygous inbred families(HIFs),SNPs were called from RNA sequencing(RNA-Seq)data for HIF-derived progenies with long and short *** between long and short awn plants were evenly distributed on chromosomes(chr)other than chromosome 5 *** on chr 5 A were clustered in a region distal 688 Mb on the long arm,where inhibitor B1 was *** suggested that B1 was the causal segregating *** precisely mapped B1 to^1 Mb region using two HIF-derived *** that the lines segregated for long,intermediate and short awn phenotypes we speculated that B1 should have a dosage effect on awn *** differentially expressed genes(DEGs)located in the candidate region were regarded as candidate genes for B1,because the molecular expression pattern was consistent with the *** with long and short awns showed no difference on grain yield and other agronomic traits.

关键词： dosage mapping evenly

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One-pot synthesis of PVP-coated Ni_(0.6)Fe_(2.4)O_4 nanocrystals

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Chinese Science Bulletin 2010年第30期55卷 3472-3478页

作者： LU XianYong niu mu YANG ChunHui YI LuoXin QIAO RuiRui DU MeiHong GAO MingYuan Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China School of Chemistry and Environment Beijing University of Aeronautics and Astronautics Beijing 100191 China Beijing Center for Physical and Chemical Analysis Beijing 100089 China

Novel poly(N-vinyl-2-pyrrolidone) (PVP)-coated nickel ferrite nanocrystals were prepared by simultaneously pyrolyzing nickel(Ⅱ) acetylacetonate (Ni(acac)2) and iron(Ⅲ) acetylacetonate (Fe(acac)3) in N-vinyl-2-pyrrolidone (NVP). The PVP coating was formed in situ through polymerization of NVP. The crystalline structure of the resultant nickel ferrite was analyzed by high-resolution transmission electron microscopy,electron diffraction patterns,and powder X-ray diffraction. In addition,the valence state of Ni and the metal contents of Ni and Fe in different valence states were analyzed by X-ray photoelectron spectroscopy (XPS),atomic absorption and the phenanthroline method. The surface coating layer of PVP and its binding states were characterized by Fourier transform infrared spectroscopy in combination with XPS. Colloidal stability experiments revealed that the nanocrystals could be dispersed well in both phosphate-buffered saline and Dulbecco's Modified Eagle Medium.

关键词：聚乙烯吡咯烷酮高分辨透射电子显微镜纳米涂层 X射线光电子能谱粉末X射线衍射傅里叶变换红外光谱镍铁氧体合成

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The physiological and pathological mechanisms of early embryonic development

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Fundamental Research 2022年第6期2卷 859-872页

作者： Jian mu Zhou Zhou qing Sang Lei Wang The State Key Laboratory of Genetic Engineering Institute of PediatricsChildren's Hospital of Fudan UniversityThe Institutes of Biomedical SciencesFudan UniversityShanghai 200032China NHC Key Lab of Reproduction Regulation Shanghai Institute for Biomedical and Pharmaceutical TechnologiesShanghai 200032China

Early embryonic development is a complex *** zygote undergoes several rounds of division to form a blastocyst,and during this process,the zygote undergoes the maternal-to-zygotic transition to gain control of embryonic development and makes two cell fate decisions to differentiate into an embryonic and two extra-embryonic *** the use of new molecular biotechnologies and animal models,we can now further study the molecular mechanisms of early embryonic development and the pathological causes of early embryonic ***,we first summarize the known molecular regulatory mechanisms of early embryonic development in *** we discuss the pathological factors leading to the early embryonic *** hope that this review will give researchers a relatively complete view of the physiology and pathology of early embryonic development.

关键词： Early embryonic development Physiology Pathology Molecular mechanism Pathogenesis

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Cobalt-loaded carbon nanotubes boosted aerobic ciprofloxacin transformation driven by sulfide:A comprehensive mechanism investigation

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Chinese Chemical Letters 2024年第3期35卷 127-134页

作者： Han-qing Zhao Peili Lu Fei Chen Chen-Xuan Li Rui Yan Yang mu State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044China CAS Key Laboratory of Urban Pollutant Conversion Department of Environmental Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment College of Environment and EcologyChongqing UniversityChongqing 400045China College of Resources and Environmental Engineering Hefei University of TechnologyHefei 230009China

Sulfide oxidation under aerobic conditions can produce active oxygen for the transformation of organic pollutants in aquatic ***,the catalytic performance of transition metal-supported carbon material on this process is poor *** study found that Co-loaded carbon nanotubes(CNTs)was able to realize the efficient aerobic transformation of antibiotic ciprofloxacin(CIP)by sulfide,with the pseudo-first order reaction rate constant improved from 0.013 h^(-1)without catalyst to 0.44–0.71 h^(-1)with 100 mg/L Co-loaded *** oxygen(^(1)O_(2))was the main active specie playing key roles in the process of CIP aerobic transformation with presence of Co-loaded *** studies indicated that the excellent electron transfer ability of Co-loaded CNTs might play an important role to promote the electron transfer and facilitate the formation of intermediate H_(2)O_(2)and^(1)O_(2).Additionally,the Co-loaded CNTs/sulfide system effectively reduced the acute toxicity of organic pollutant,and Co-loaded CNTs showed remarkable cycling stability and negligible *** study gives a better understanding for the Co-loaded CNTs mediated aerobic antibiotics transformation by sulfide,and provide a reference for the application of Co-loaded carbon materials on organics aerobic transformation by sulfide.

关键词： Ciprofloxacin Aerobic transformation Co-loaded carbon nanotubes Sulfide Singlet oxygen

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Components of Volatile Oil from Water-caltrop and Their Anti-tumor Effect in vitro

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Chemical Research in Chinese Universities 2009年第1期25卷 56-59页

作者： ZHAO Wen-jing niu Feng-lan LI Jing DONG qing HUANG Zhan-you School of Public Health Jilin University Changchun 130021 P. R. China

The volatile oil was extracted from water caltrop by steam distillation; it was then analyzed by GC-MS to obtain 16 components, 8 of which were identified. Apocynin was the most abundant one, accounting for 81.41% of the total oil. The in vitro inhibitory effects of the volatile oil on SMMC-7721, MCF-7, Hela, HL-60 cells, and human peripheral blood mononuclear cells（PBMC） were investigated via the MTT method. The morphological changes of the tumor cells were observed and the apoptosis of HL-60 cells was detected by flow cytometry. The proliferation of the tumor cells could be significantly inhibited and the apoptosis of HL-60 cells could be induced by the volatile oil. The proliferation inhibition effect of the volatile oil on HL-60 tumor cells and the induction of the apoptosis of ilL-60 cells had dose-dependent feature.

关键词： Water caltrop Volatile oil Tumor Apoptosis

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Design and synthesis of hybrid solids based on the tetravanadate core toward improved catalytic properties

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Chinese Chemical Letters 2016年第5期27卷 649-654页

作者： Yan-Hong niu Song Yang Ji-Kun Li Yan-qing Xu Chang-Wen Hu Key Laboratory of Cluster Science Ministry of Education of China Beijing Key Laboratory of PhotoelectronicElectrophotonic School of Chemistry Beijing Institute of Technology

Five inorganic-organic hybrid vanadates based on tetravanadate cores, transition metals and N-donor ligands have been designed and synthesized under hydrothermal conditions, namely, [Zn（elM）312V4O12 （1）, [Zn（plM）3]2V4O12.H2O （2）, [Zn（iplM）3]2V4O12 （3）, [Co（eIM）3]2V4O12.H2o （4）, [Cu（eIM）2（H20）]2V4O12 （5）（eIM = 1-ethylimidazole, plM = 1-propylimidazole, ipIM = isopropylimidazole）. All compounds were fully characterized by single-crystal XRD, powder XRD, elemental analysis, TGA, and FT-IR spectroscopy. The hybrid zinc vanadates （1-3） and cobalt vanadate （4） exhibit interesting 2D folded structures and the hybrid copper vanadate （5） presents a 1D chain configuration. All compounds can catalyze olefin epoxidation reactions when using TBHP （TBHP = tert-butyl hydroperoxide） as an oxidant in acetonitrile. The introduction of transition metal ions into tetravanadate cores not only improved the catalytic activity but also fulfilled the heterogeneous catalytic behavior. 1-5 all exhibit extraordinary efficiency in converting olefins to the corresponding epoxides with high conversion and selectivity （particularly, cony. up to 97.1%, sele. up to 100% for 1 ）. Leaching test was also carried out to prove the heterogeneous behavior.

关键词： Hybrid Tetrvanadate core Heterogeneous catalysts Olefin epoxidation

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Human induced dryland degradation in Ordos Plateau,China,revealed by multilevel statistical modeling of normalized difference vegetation index and rainfall time-series

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Journal of Arid Land 2014年第2期6卷 219-229页

作者： Jing ZHANG JianMing niu Tongliga BAO Alexander BUYANTUYEV qing ZHANG JianJun DONG XueFeng ZHANG College of Life Sciences Inner Mongolia University College of Environment and Resources Dalian Nationalities University Sino-US Center for Conservation Energyand Sustainability ScienceInner Mongolia University Faculty of Resources and Environment Baotou Teachers College Department of Botany and Plant Sciences University of California

Land degradation causes serious environmental problems in many regions of the world, and although it can be effectively assessed and monitored using a time series of rainfall and a normalized difference vegetation index （NDVI） from remotely-sensed imagery, dividing human-induced land degradation from vegetation dynamics due to climate change is not a trivial task. This paper presented a multilevel statistical modeling of the NDVI-rainfall relationship to detect human-induced land degradation at local and landscape scales in the Ordos Plateau of Inner Mongolia, China, and recognized that anthropogenic activities result in either positive （land restoration and re-vegetation） or negative （degradation） trends. Linear regressions were used to assess the accuracy of the multi- level statistical model. The results show that：（1） land restoration was the dominant process in the Ordos Plateau between 1998 and 2012; （2） the effect of the statistical removal of precipitation revealed areas of human-induced land degradation and improvement, the latter reflecting successful restoration projects and changes in land man- agement in many parts of the Ordos; （3） compared to a simple linear regression, multilevel statistical modeling could be used to analyze the relationship between the NDVI and rainfall and improve the accuracy of detecting the effect of human activities. Additional factors should be included when analyzing the NDVI-rainfall relationship and detecting human-induced loss of vegetation cover in drylands to improve the accuracy of the approach and elimi- nate some observed non-significant residual trends.

关键词： NDVl-rainfall relationship anthropogenic activities multilevel statistical modeling land degradation dryland Ordos Plateau

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