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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 management.This study proposed a novel approach to predict SOM with high accuracy using multiyear synthetic remote sensing variables on a monthly scale.We 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 images.Then 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 variables.Results showed that firstly,all monthly synthetic spectral bands of Sentinel-2 showed a significant correlation with SOM(P<0.05)for the months of January,March,April,October,and November.Secondly,in terms of single-monthly composite variables,the prediction accuracy was relatively poor,with the highest R^(2)value of 0.36 being observed in January.When monthly synthetic environmental 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 accuracy.The overall best performance was observed when all monthly synthetic variables were incorporated into the models.Thirdly,among the three models compared,the RF model was consistently more accurate than the SVM and GBRT models,achieving an R^(2)value of 0.56.Except for band 12 in December,the importance of the remaining bands did not exhibit significant differences.This 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

Molecular phylogeny and historical biogeography of the cave fish genus Sinocyclocheilus(Cypriniformes:Cyprinidae)in southwest China

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Integrative Zoology 2022年第2期17卷 311-325页

作者： Huamei WEN Tao LUO Yali wang siwei wang Tao LIU Ning XIAO Jiang ZHOU School of Life Sciences Central China Normal UniversityWuhanChina School of Karst Sciences Guizhou Normal UniversityGuiyangChina School of Life Sciences Guizhou Normal UniversityGuiyangChina Department of Senior High School Liupanshui No.4 Higth SchoolLiupanshuiChina Department of Basic Medicine Guiyang Nursing Vocational CollegeGuiyangChina

Modern accumulations of genetic data offer unprecedented opportunities for understanding the systematic classification and origins of specific groups of organisms.The genus Sinocyclocheilus is among the most cave abundant genera in Cyprinidae,with 76 recognized species,belonging to 4 species groups.Recent phylogenetic studies have shown that the classification of species groups within the genus Sinocyclocheilus remains controversial.In this study,we constructed a sequence supermatrix of 26 species from 4 species groups of the genus Sinocyclocheilus using the mitochondrial genome to reveal phylogenetic relationships,historical biogeography and patterns of species diversification in the genus Sinocyclocheilus.Phylogenetic analysis strongly supports the monophyletic groups of the 3 species groups(S.jii,S.cyphotergous,and S.tingi groups)except the S.angularis group.Phylogenetic analysis showed that S.anshuiensis and S.microphthalmus,which were recognized as numbers of S.angularis group,formed a strongly supported independent clade.Therefore,we propose a new species group,the S.microphthalmus group,which contains S.anshuiensis and S.microphthalmus.Biogeographic reconstruction suggests that the living Sinocyclocheilus may have originated in north-central Guangxi at the late Eocene and dispersed outward after a vicariance at 32.31 Million years ago(Ma).Early diversification is focused on the late Oligocene(ca.25 Ma),which is related to the second uplift of the Qinghai−Tibetan Plateau and the lateral extrusion of the Indochina at the Oligocene/Miocene boundary.Our results suggest that 2 uplifts of the Qinghai−Tibetan Plateau and climate change in the Miocene may have influenced the diversification of the Sinocyclocheilus lineage.

关键词： biogeography cave fish karst phylogeny Sinocyclocheilus

Photodegradation of new herbicide HW-02 in organic solvents

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Journal of Environmental Sciences 2010年第11期22卷 1774-1778页

作者： Zhongbin Lu Zhiguang Hou Xiumei wang siwei wang Yanyan Shang Xing Yuan College of Urban and Environmental Science Northeast Normal University Changchun 130024 China. College of Resource and Environmental Science Jilin Agricultural University Changchun 130118 China The Center for Measurement and Test Jilin Agricultural University Changchun 130118 China Institute of Modernization Jilin Agricultural University Changchun 130118 China

HW-02 is a new organophosphates herbicide which is discovered and developed in China. The kinetics and mechanism of HW-02 photodegradation in the organic solvents were studied at 25°C under the irradiation of ultraviolet light. The results showed that photochemical reaction of HW-02 in organic solvents such as n-hexane, methanol, dimethyl benzene and acetone under UV light could be well described by the first kinetic equation, and the photodegradation efficiency decreased with a order of n-hexane methanol xylene acetone. The photodegradation efficiency constant of HW-02 in n-hexane, methanol, xylene and acetone were 4.951 × 10^-2 , 3.253 × 10^-2 , 2.377 × 10^-2 and 1.628 × 10^-2 min 1 , and the corresponding half-lives were 13.99, 21.20, 29.15 and 42.56 min, respectively. By separation and identification of photoproducts using GC-MS, it could be concluded that HW-02 was photolyzed through ester cleavage, photo-dechlorination and photoisomerization of the molecule itself.

关键词： HW-02 organic solvent photodegradation kinetics degradation mechanism

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吉林省伊舒盆地地热流体特性及储量计算

中国地质调查 2024年第1期11卷 36-44页

作者：王思维王思微姜峰何双凤高鹤吉林省水文地质调查所吉林长春130103

吉林省伊舒盆地地层富水性良好、地热资源丰富,具有良好的地热资源开发利用前景。基于研究区伊舒盆地已有地热地质调查和评价资料,结合相关标准、规范和水化学方法,梳理分析研究区水文地质和地热地质条件,探讨了研究区内地热流体赋存条... 详细信息

吉林省伊舒盆地地层富水性良好、地热资源丰富,具有良好的地热资源开发利用前景。基于研究区伊舒盆地已有地热地质调查和评价资料,结合相关标准、规范和水化学方法,梳理分析研究区水文地质和地热地质条件,探讨了研究区内地热流体赋存条件、水化学和同位素组成特征,并利用热储岩体参数计算研究区的地热储量。结论表明:研究区地热流体主要赋存于深层碎屑岩类裂隙孔隙中,形成条件具有较高相似性和一定的同源性,溶解性固体(total dissolved solids,TDS)较高、含氟和偏硅酸的低温碱性地下热水,水化学类型为HCO_(3)^(-)-Na^(+)型。氢氧同位素组成表明,研究区地下流体补给以古降水为主,地热流体年龄为27 Ka。地热流体储存水量为4.20×10^(10)m^(3),年可开采量为3446.94×10^(4)m^(3)/a。研究成果可为吉林省后续地热资源管理、开发和利用提供科学依据。

关键词：吉林省伊舒盆地地热流体水化学特征地热储量

Frequent detection of genetic aberrations reveals novel pathogenesis and treatment modalities in systemic juvenile xanthogranuloma

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Pediatric Investigation 2023年第3期7卷 212-215页

作者： Jiaosheng Xu Hongyan Ma Xingfeng Yao Xiaofeng Han Yang Wen siwei wang Zigang Xu Lin Ma Department of Dermatology Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina Department of Dermatology Children’s Hospital of Xinjiang Uygur Autonomous RegionXinjiang Hospital of Beijing Children’s HospitalXinjiangChina Department of Pathology Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina Department of Radiology Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina Department of Ultrasound Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina

Juvenile xanthogranuloma(JXG),the most common form of non-Langerhans cell histiocytosis(non-LCH),is generally confined to the skin during infancy and early childhood.^(1)JXG rarely involves extracutaneous tissues or systemic organs,resulting in high morbidity and mortality rates.Clonality in JXG has been verified by histopathological and genetic analyses,which have shown it to be tumorous rather than a reactive disorder of JXG.^(2)However,the exact etiopathogenesis of JXG remains unclear.

关键词： treatment organs exact

A New Species of Odorous Frog Genus Odorrana(Anura,Ranidae) from Southern Guizhou Province,China

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Asian Herpetological Research 2021年第4期12卷 381-398页

作者： Tao LUO siwei wang Ning XIAO Yali wang Jiang ZHOU School of Karst Science Guizhou Normal UniversityGuiyang 550001GuizhouChina School of Life Sciences Guizhou Normal UniversityGuiyang 550001GuizhouChina Guiyang Nursing Vocational College Guiyang 550003GuizhouChina

We describe Odorrana liboensis sp.nov.,a new species from the Maolan National Nature Reserve,Libo County,Guizhou Province,China.Phylogenetic analyses based on DNA sequences of the mitochondrial 12 S rRNA,16 S rRNA,and ND2 genes supported the new species as an independent lineage,closely related to O.lipuensis.The uncorrected genetic distances between the 12 S rRNA and16 S rRNA in the new species and its closest congener,O.lipuensis,were 6.06%and 5.19%,respectively.The new species is distinguished from its congeners by a combination of the following morphological characters:(1)having medium body size,with the snout-vent length(SVL)of adult females approximately 1.2 times as long as males at 56.9±1.0(55.8-58.2 mm,n=9)in females and 48.7±1.2(47.1-49.9 mm,n=5)in males;(2)head length greater than width in males and females;(3)tympanum distinctly visible,greater than one-half the diameter of the eye;(4)eyes big and prominent,width of upper eyelid(UEW)approximately3/4 of eye diameter(ED);(5)dorsolateral folds absent;(6)two metacarpal tubercles;(7)relative finger lengths:Ⅱ<Ⅰ<Ⅳ<Ⅲ;(8)subarticular tubercles on fingers prominent:1,1,2,2;(9)one metatarsal tubercle;(10)tibiotarsal articulation reaching to between the eye and nostril when the leg is stretched forward;(11)toes with entire webbing to disks;(12)subarticular tubercles on toes prominent:1,1,2,3,2;(13)dorsal surfaces of limbs with distinct brownish-black bands;(14)smooth,grass-green dorsum with irregular brown mottling;(15)venter smooth,lacking black spots;and(16)lacking pectoral spinules,lacking vocal sacs,and light white nuptial pad present on finger I in males.The new species is currently only known from the type locality.

关键词： Taxonomy morphology Odorrana Odorrana liboensis sp.nov. karst cave Guizhou

基于超级电容器的核聚变磁体电源系统环形场线圈电源设计

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南方能源建设 2024年第3期11卷 117-125页

作者：许一泽林睿王思巍中国能源建设集团广东省电力设计研究院有限公司广东广州510663

[目的]研究旨在为核聚变磁体电源系统中的环形场线圈开发一种高效可靠的脉冲电源系统。针对核聚变装置在高功率需求下的挑战,提出了一种基于超级电容器的电源解决方案,旨在增强能量存储的效率和系统的稳定性。[方法]通过采用模块化多级... 详细信息

[目的]研究旨在为核聚变磁体电源系统中的环形场线圈开发一种高效可靠的脉冲电源系统。针对核聚变装置在高功率需求下的挑战,提出了一种基于超级电容器的电源解决方案,旨在增强能量存储的效率和系统的稳定性。[方法]通过采用模块化多级转换器技术,开发了一种新型的脉冲电源结构。利用超级电容器的高功率密度和快速充放电能力,作为主要的能量存储单元,以满足环形场线圈的高频脉冲运行需求。此外,探讨了超级电容器与模块化多级转换器技术结合的优势,如系统的灵活性和可扩展性。[结果]研究结果显示,所开发的电源系统能够有效支持核聚变反应堆的脉冲操作需求,确保了能量的高效输送和转换。[结论]基于超级电容器的脉冲电源系统为核聚变装置提供了一种有效的能量解决方案。该系统不仅提高了能量转换的效率,也增强了整个设备的运行稳定性和可靠性。未来的研究将进一步优化电源结构和性能,以适应更广泛的应用场景。

关键词：核聚变磁体电源系统飞轮发电机环形场线圈超级电容器模块化多电平转换器

国际碳减排机制中的碳信用适用冲突问题研究——以国际航空碳减排为视角

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国际法研究 2024年第2期 113-126页

作者：李万强王思炜西安交通大学法学院

作为碳减排机制核心要素的两种排放单位之一,碳信用在国际航空碳减排领域得到了更为广泛的适用。实践中,国际航空运输所具备的跨国性特征使其相较于其他行业更容易受到多项减排机制的规制和管辖,国际航班运营人也需要依照不同机制的要... 详细信息

作为碳减排机制核心要素的两种排放单位之一,碳信用在国际航空碳减排领域得到了更为广泛的适用。实践中,国际航空运输所具备的跨国性特征使其相较于其他行业更容易受到多项减排机制的规制和管辖,国际航班运营人也需要依照不同机制的要求提交碳信用、履行减排义务。但包括国际民航组织“国际航空碳抵消与减排计划”在内的不同减排机制对碳信用的适用规则与认定标准存在差异,在国际碳减排机制存在交叉或重叠适用的背景下,不可避免地会产生碳信用的种类、期限与效力等冲突。此外,因欧盟碳交易机制拒绝承认碳信用的抵免资格,又会引发碳信用的资格冲突。以上冲突不仅阻碍国际航空碳减排工作的开展,还不合理地增加了各减排责任主体的抵免负担。为解决前述问题,国际社会可尝试从明确各机制间的关系、规范减排项目及其成果的认定程序以及回应欧盟对碳信用质量的关切等方面有针对性地采取措施。中国作为经济发展与碳排放大国,有必要结合航空产业现状,制定能够维护中国合法利益、兼顾各方需求的有效应对方案。

关键词：国际航空碳减排排放单位碳信用适用冲突