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南海北部内孤立波影响海域悬浮颗粒物特征变化研究

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海洋学报 2024年第6期46卷 114-129页

作者：王宏威乔玥冯学志朱超祁陈天胡聪孙中强孙均凯单红仙贾永刚中国海洋大学山东省海洋环境地质工程重点实验室山东青岛266100 中国海洋大学海洋环境与生态教育部重点实验室山东青岛266100 中国海洋大学海底科学与探测技术教育部重点实验室山东青岛266100

悬浮颗粒物在“源-汇”沉积体系中扮演着关键角色,而南海常见的动力现象—内孤立波,则被证实是影响悬浮颗粒物分布和沉积过程的重要因素。该项研究于2022年9月在吕宋海峡至东沙群岛海域开展,采用LISST-deep与CTD设备进行同步观测,以研... 详细信息

悬浮颗粒物在“源-汇”沉积体系中扮演着关键角色,而南海常见的动力现象—内孤立波,则被证实是影响悬浮颗粒物分布和沉积过程的重要因素。该项研究于2022年9月在吕宋海峡至东沙群岛海域开展,采用LISST-deep与CTD设备进行同步观测,以研究悬浮颗粒物的粒径及体积浓度分布。通过调查期内的卫星遥感数据,划定了内孤立波的影响范围,并结合海床基观测内孤立波影响悬浮颗粒物分布过程,从动力学的角度揭示了内孤立波对悬浮颗粒物在输运过程中特征变化的影响。研究发现:(1)在内孤立波的振幅深度区间(6~79 m)内,以较小粒径的悬浮颗粒物(15~25μm)分布为主,且越接近内孤立波的波谷深度,出现较小粒径悬浮颗粒物的频率越高。(2)悬浮颗粒物分布由内孤立波波峰线中心区域扩散到两侧,在中心为体积浓度低值区(≤91μL/L),而波峰线两侧区域与内孤立波传播路径远端区域为体积浓度高值区(≥500μL/L)。此外,研究进一步揭示了内孤立波通过改造作用使聚集状态的悬浮颗粒物被分解为粒径较小、组成单一的颗粒,通过控制作用改变悬浮颗粒物在波峰线不同位置、传播路径和振幅深度上的体积浓度分布,为理解南海源-汇沉积体系提供了重要的理论依据。

关键词：内孤立波悬浮颗粒物粒径分布颗粒特征改造控制作用

Effect of Uncertainty of Grid DEM on TOPMODEL:Evaluation and Analysis

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Chinese Geographical Science 2006年第4期16卷 320-326页

作者： WANG Peifa DU Jinkang feng xuezhi KANG Guoding Department of Geographic Information Science Nanfing University Nanfing 210093 China Department of Demography and Economics Nanjing College for Population Programme Management Nanfing 210042 China

TOPMODEL,a semi-distributed hydrological model,has been widely *** the process of simulation of the model,Digital Elevation Model(DEM) is used to provide the input data,such as topographic index and distance to the drainage outlet;thus DEM plays an important role in *** study aims at examining the impacts of DEM uncertainty on the simulation results of *** this paper,the effects were evaluated mainly from quantitative and qualitative ***,DEM uncertainty was simulated by using the Monte Carlo method,and for every DEM realization,the topographic index and distance to the drainage outlet were ***,the obtained topographic index and the distance to the drainage outlet were input to the TOPMODEL to simulate seven rain-storm-flood events,and four evaluation indices,such as Nash and Sutcliffe efficiency criterion(EFF),sum of squared residuals over all time steps(SSE),sum of squared log residuals over all time steps(SLE) and sum of absolute errors over all time steps(SAE) were ***,these four evaluation indices were analyzed in statistical manner(minimum,maximum,range,standard deviation and mean value),and effect of DEM uncertainty on TOPMODEL was quantitatively ***,the simulated hydrographs from TOPMODEL using the original DEM and realizations of DEM were qualitatively evaluated under each flood *** show that the effect of DEM uncertainty on TOPMODEL is inconsiderable and could be ignored in the model’s *** can be explained by:1) TOPMODEL is not sensitive to the distribution of topographic index and distance to the drainage outlet;2) the distri-bution of topographic index and distance to the drainage outlet are slightly affected by DEM uncertainty.

关键词：网格DEM TOPMODEL 不确定性蒙特卡罗模拟水位图原始数据

A Method for Retrieving Water-leaving Radiance from Landsat TM Image in Taihu Lake, East China

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Chinese Geographical Science 2007年第4期17卷 364-369页

作者： WANG Deyu feng xuezhi MA Ronghua KANG Guoding Department of Geographic and Information Science Nanjing University Nanjing 210093 China Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China Department of Demography and Economics Nanjing College for Population Programme Management Nanjing 210042 China

The visible and infrared bands of Landsat Thematic Mapper (TM) can be used for inland water studies. A method of retrieving water-leaving radiance from TM image over Taihu Lake in Jiangsu Province of China was investigated in this article. To estimate water-leaving radiance, atmospheric correction was performed in three visible bands of 485nm, 560nm and 660nm. Rayleigh scattering was computed precisely, and the aerosol contribution was estimated by adopting the clear-water-pixels approach. The clear waters were identified by using the Landsat TM middle-infrared band (2.1μm), and the water-leaving radiance of clear water pixels in the green band was estimated by using field data. Aerosol scattering at green band was derived for six points, and interpolated to match the TM image. Assuming the atmospheric correction coefficient was 1.0, the aerosol scattering image at blue and red bands were derived. Based on a simplified atmospheric radiation transfer model, the water-leaving radiance for three visible bands was retrieved. The water-leaving radiance was normalized to make it comparable with that estimated from other remotely sensed data acquired at different times, and under different atmospheric conditions. Additionally, remotely sensed reflectance of water was computed. To evaluate the atmospheric correction method presented in this article, the correlation was analyzed between the corrected remotely sensed data and the measured water parameters based on the retrieval model. The results show that the atmospheric correction method based on the image itself is more effective for the retrieval of water parameters from Landsat TM data than 6S (Second Simulation of the Satellite Signal in the Solar Spectrum) code based on standard atmospheric and aerosol models.

关键词：提取方法中国太湖陆地卫星 TM成像

Using autologistic spatial models to simulate the distribution of land-use patterns in Zhangjiajie, Hunan Province

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Journal of Geographical Sciences 2010年第2期20卷 310-320页

作者： WU Guiping ZENG Yongnian XIAO Pengfeng feng xuezhi HU Xiaotian Department of Geographical Information Sciences Nanjing University Nanjing 210093 China School of Info-Physics and Geomatics Engineering Central South University Changsha 410083 China

Nowadays, spatial simulation on land use patterns is one of the key contents of LUCC. Modeling is an important tool for simulating land use patterns due to its ability to integrate measurements of changes in land cover and the associated drivers. The conventional regression model can only analyze the correlation between land use types and driving factors but cannot depict the spatial autocorrelation characteristics. Land uses in Yongding County, which is located in the typical karst mountain areas in northwestern Hunan province, were investigated by means of modeling the spatial autocorrelation of land use types with the purpose of deriving better spatial land use patterns on the basis of terrain characteristics and infrastructural conditions. Through incorporating components describing the spatial autocorrelation into a conventional logistic model, we constructed a regression model （Autologistic model）, and used this model to simulate and analyze the spatial land use patterns in Yongding County. According to the comparison with the conventional logistic model without considering the spatial autocorrelation, this model showed better goodness and higher accuracy of fitting. The distribution of arable land, wood land, built-up land and unused land yielded areas under the ROC curves （AUC） was improved to 0.893, 0.940, 0.907 and 0.863 respectively with the autologistic model. It is argued that the improved model based on autologistic method was reasonable to a certain extent. Meanwhile, these analysis results could provide valuable information for modeling future land use change scenarios with actual conditions of local and regional land use, and the probability maps of land use types obtained from this study could also support government decision-making on land use management for Yongding County and other similar areas.

关键词： land-use patterns spatial simulation autologistic model spatial autocorrelation Yongding County of Zhangjiajie City

Poisoning effect of polyvinyl chloride on the catalytic pyrolysis of mixed plastics over zeolites

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Science China Chemistry 2024年第7期67卷 2265-2273页

作者： Jiangchun Yuan Wenjie Wang Weixiao Sun Zhirong Yang Yueqiang Cao Wenyao Chen Xiaohu Ge Gang Qian Xiang feng xuezhi Duan Xinggui Zhou Kevin M.Van Geem Jing Zhang State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China Laboratory for Chemical Technology(LCT) Department of MaterialsTextiles and Chemical EngineeringFaculty of Engineering&ArchitectureGhent UniversityZwijnaarde B-9052Belgium State Key Lab of Heavy Oil Processing China University of PetroleumQingdao 266580China

Nowadays,the chemical recycling is applied for only 1%of total waste plastics,largely due to contaminants in plastic waste and difficulty in product *** the major contaminant,polyvinyl chloride(PVC)often forms corrosive hydrogen chloride(HCl)during the chemical recycling,which may cause severe catalyst deactivation and equipment ***,the investigation on catalytic pyrolysis(the major route for plastics chemical recycling)of the PVC containing mixed plastics has been rarely ***,catalytic co-pyrolysis of PVC and polyethylene(PE)was studied over an aromatization catalyst,Pt/ZSM-5,since the basic building block aromatics are desired products from plastics chemical *** poisoning effect of PVC vapor on the catalyst stability was explored by collective efforts of thorough product analysis and catalyst *** was found that the HCl evolving from PVC has an autocatalytic effect that promotes the scission of dehydrochlorinated PVC,resulting in the high yield of benzene and acetylene from *** the other hand,the presence of PVC suppressed the aromatics formation from PE,largely due to the poisoning effect of PVC-derived HCl on the Pt/*** deactivation is irreversible as evidenced by the decreased zeolite crystallinity and the loss of strong acid sites that are key to the aromatization,possibly due to the removal of framework Al upon the interaction with *** modification with octadecylphosphonic acid only slightly alleviated the PVC poisoning *** insights on the PVC poisoning of zeolite catalysts provided in this work may guide the process design of chemical recycling of PVC containing waste plastics.

关键词： polyvinyl chloride polyethylene zeolite aromatics deactivation

China's lakes at present:Number,area and spatial distribution

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Science China Earth Sciences 2011年第2期54卷 283-289页

作者： MA RongHua YANG GuiShan DUAN HongTao JIANG JiaHu WANG SuMin feng xuezhi LI AiNong KONG FanXiang XUE Bin WU JingLu LI ShiJie State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China Department of Geographic Information Science Nanjing University Nanjing 210093 China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China

Based on 11004 satellite images from CBERS CCD and Landsat TM/ETM,changes in the spatial characteristics of all lakes in China were determined following pre-established interpretation *** dataset was supported by 6843 digital raster images(1:100000 and 1:50000),a countrywide digital vector dataset(1:250000),and historical *** data were corrected for seasonal variations using precipitation *** are presently 2693 natural lakes in China with an area greater than 1.0 km2,excluding *** lakes are distributed in 28 provinces,autonomous regions and municipalities and have a total area of 81414.6 km2,accounting for-0.9% of China's total land *** the past 30 years,the number of newly formed and newly discovered lakes with an area greater than 1.0 km2 is 60 and 131,***,243 lakes have disappeared in this time period.

关键词：湖泊变化湖泊面积中国空间分布中巴地球资源卫星陆地卫星TM 〇平方技术手册

基于道路网络分析的Voronoi面域图构建算法

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测绘学报 2010年第1期39卷 88-94页

作者：谢顺平冯学智鲁伟南京大学地理与海洋科学学院江苏南京210093

提出一种基于网络分析的Voronoi面域图和加权Voronoi面域图构建算法。鉴于道路网络在城市中心地、公共设施引力传导与功能覆盖上的重要作用,采用网络最短路径距离分析和最短路径时间分析构建的Voronoi面域图可以模拟出中心功能的辐射影... 详细信息

提出一种基于网络分析的Voronoi面域图和加权Voronoi面域图构建算法。鉴于道路网络在城市中心地、公共设施引力传导与功能覆盖上的重要作用,采用网络最短路径距离分析和最短路径时间分析构建的Voronoi面域图可以模拟出中心功能的辐射影响范围空间划分的实际情形,进而为空间分析和空间优化提供有力支持。算法过程主要包括:设施邻近道路结点检索和分界结点计算;基于网络最短路径分析Dijkstra算法和分界结点计算的网络Voronoi划分;基于空间离散化、邻近道路分析的空间Voronoi划分及其矢量化处理算法。计算实验结果表明本文提出算法可靠和高效,能够模拟出具有预期精度和形态复杂的网络Voronoi面域图形。

关键词：网络Vo ronoi面域图网络分析空间划分功能辐射域路径时间距离

基于多分类器结合的IKONOS影像城市植被类型识别

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东南大学学报（自然科学版） 2007年第3期37卷 399-403页

作者：张秀英冯学智刘伟浙江大学农业遥感与信息技术应用研究所杭州310029 南京大学地理与海洋科学学院南京210093

采用多分类器结合的方法对城市植被进行分类.首先,以分割获得的城市植被分布斑块为处理基元,在不同特征空间中采集不同的样本,通过ISODATA、马氏距离、最大似然、人工神经网络和专家系统法进行分类,并计算各分类结果的关联程度和各植被... 详细信息

采用多分类器结合的方法对城市植被进行分类.首先,以分割获得的城市植被分布斑块为处理基元,在不同特征空间中采集不同的样本,通过ISODATA、马氏距离、最大似然、人工神经网络和专家系统法进行分类,并计算各分类结果的关联程度和各植被类型识别的先验概率;然后利用专家投票的大多数规则对分类结果组合,未分类的对象按照先验识别概率最高的结果归类.精度评价表明:多分类器结合方法显著提高了信息识别的能力;采用多分类器结合的方法比单个分类器获得的最高分类精度提高5.5%,Kappa系数提高7.4%;Z统计值均为负,且均通过95%的置信水平检验.

关键词：城市植被投票规则多分类器

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苏北原生金刚石找矿现存问题探讨

中国地质调查 2022年第5期9卷 79-88页

作者：张琪周琦忠王博王国强冯学知罗跃江苏省地质矿产局第五地质大队江苏徐州221004

苏北第二轮金刚石找矿历时8 a,尚未发现含矿的金伯利岩或金刚石矿床。从苏北找矿实际出发,结合最新的金刚石成矿理论和进展,提出和探讨了制约苏北原生金刚石找矿的几个问题,进一步探讨了找矿方向。研究认为:苏北原生金刚石找矿的首要目... 详细信息

苏北第二轮金刚石找矿历时8 a,尚未发现含矿的金伯利岩或金刚石矿床。从苏北找矿实际出发,结合最新的金刚石成矿理论和进展,提出和探讨了制约苏北原生金刚石找矿的几个问题,进一步探讨了找矿方向。研究认为:苏北原生金刚石找矿的首要目标为古生代金伯利岩,在郯庐断裂带西侧,由于徐宿弧形构造的存在,可能使得该期金伯利岩被掩盖于推覆体之下;郯庐断裂带与古生代金伯利岩没有成因联系,但其在伸展阶段控制发育的断陷红盆,可能使得带内的古生代金伯利岩被掩盖在白垩系之下。今后的找矿方向应重点集中在郯庐断裂带内的城岗隆起上,郯庐断裂带西侧的含角砾基性岩亦是值得关注的对象。在开展找矿勘查时,应充分考虑工作区地质与地形条件、方法适应性和局限性等因素,因地制宜选择勘查方法组合。

关键词：苏北地区原生金刚石找矿金伯利岩构造找矿方向