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基于红(R)绿(G)蓝(B)三波段的典型港湾透明度反演研究

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海洋与湖沼 2024年第3期55卷 651-659页

作者：朱元励毛铭郭然杜萍陶邦一江志兵曾江宁自然资源部第二海洋研究所自然资源部海洋生态系统动力学重力实验室浙江杭州310012 浙江省近海海洋工程环境与生态安全重点实验室浙江杭州310012 浙江工商大学环境科学与工程学院浙江杭州310012 浙江省海洋科学院海洋空间资源管理技术重点实验室浙江杭州310012 自然资源部长三角海洋生态环境科学野外观测研究站浙江舟山316021 自然资源部第二海洋研究所卫星海洋环境动力学国家重点实验室浙江杭州310012

基于卫星遥感的透明度(Secchi depth,SD)反演方法已经在大洋、近海、湖泊等不同水体开展了广泛应用。富营养化河口港湾等水体具有水域面积小且受陆地影响大等特点,并且在此类水体开展环境监测具有时效性要求。受时间空间分辨率以及云层... 详细信息

基于卫星遥感的透明度(Secchi depth,SD)反演方法已经在大洋、近海、湖泊等不同水体开展了广泛应用。富营养化河口港湾等水体具有水域面积小且受陆地影响大等特点,并且在此类水体开展环境监测具有时效性要求。受时间空间分辨率以及云层覆盖、大气校正等影响,基于卫星遥感方法在河口港湾等小水域进行透明度反演会受到一定的应用限制,因此在此类特征水体建立一种高效便捷的透明度反演方法作为卫星遥感方法的有益补充就十分迫切。本研究尝试通过无人机和智能手机应用程序HydroColor APP搭载的普通光学相机构建基于红(red,R)绿(green,G)蓝(blue,B)三波段的象山港透明度反演方法。结果表明,无人机和HydroColor的红蓝波段比值(R/B)和红绿波段比值(R/G)与透明度具有显著负相关,相关系数R为–0.88~–0.93.n=16,P3.HydroColor反演模型要优于无人机反演模型。通过以上结果分别构建基于无人机DJI-R/G和HydroColor-R/G最优透明度指数反演模型。DJI-R/G模型平均相对误差和均方根误差为29%和0.3.m,HydroColor-R/G模型为21.9%和0.27 m。以上结果表明,通过无人机和手机获取RGB信息均可用于对象山港透明度进行反演。该方法的建立为快速便捷开展河流港湾等水体的水质监测和赤潮防控提供了新的技术支持。

关键词：透明度红绿蓝(red green blue,RGB) 遥感反演无人机手机APP 象山港

Climate change risk assessment for ski areas in china

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Advances in Climate Change Research 2023年第2期14卷 300-312页

作者： Jie DENG tao CHE Yan-Xing HU Shan-Na yue Jing-Hu PAN Li-Yun DAI Heihe Remote Sensing Experimental Research Station Key Laboratory of Remote Sensing of Gansu ProvinceNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China state key laboratory of Tibetan Plateau Earth System Resources and EnvironmentInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100049China College of resource and Environment University of Chinese Academy of SciencesBeijing 100049China College of Geography and Environment Science Northwest Normal UniversityLanzhou 730070China

The successful bid for the 2022 Winter Olympics has provided a strong impetus for the development of china's ski *** areas have sprung up throughout the country,even in the low latitudes south of 3.°***,ski tourism is extremely susceptible to weather and climate *** the context of global warming,it has become important to assess the climate reliability of ski ***,this study demonstrates a novel approach to assessing the ski tourism sector's climate risks,which can be easily applied in other markets catering to the same *** the random forest regression model based on climate projections and survey data,we projected the ski season start dates,end dates and season lengths of 694 existing ski areas in china under three emission scenarios(RCP2.6,RCP4.5 and RCP8.5).Climate projections,including air temperature,snowfall,rainfall,wind speed and air humidity,were the ensemble means from five climate *** indicate that ski areas in china may have later start dates,earlier end dates and shorter ski seasons before *** the 2090s,under RCP2.6,RCP4.5 and RCP8.5,20%(13.),28%(195)and 3.%(245)of ski areas are projected to be at high climate risk(ski season less than 60 d),respectively,while 28%(197),23.(157)and 8%(56)of ski areas are at low climate risk(ski season with at least 100 d),*** climate risks are ranked from the highest to lowest in East,Central,Southwest,North,Northwest and Northeast ***,the ski tourism sector in the latitudes south of 40°N is exposed to much higher climate risks than in areas north of 40°***,climatic reliability should be carefully considered before establishing or expanding ski areas to avoid unnecessary {3. waste and ecological damage,as well as to promote sustainable development in mountain areas.

关键词： Climate risk Ski tourism Sustainability Machine learning china

Geology and mineralization of the Daheishan supergiant porphyry molybdenum deposit(1.65 Bt),Jilin,china:A review

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china Geology 2023年第3期6卷 494-530页

作者： Nan Ju Di Zhang guo-bin Zhang Sen Zhang Chuan-tao Ren Yun-sheng Ren Hui Wang yue Wu Xin Liu Lu Shi Rong-rong guo Qun Yang Zhen-ming Sun Yu-jie Hao Shenyang Center China Geological SurveyMinistry of Natural Resources(Northeast Geological S&T Innovation Center)Shenyang 110034China Mining College Liaoning Technical UniversityFuxin 123000China Cores and Samples Centre of Natural resources China Geological SurveyMinistry of Natural ResourcesLangfang 065200China Mudanjiang Natural resources Survey Center China Geological SurveyMinistry of Natural ResourceMudanjiang 157000China Institute of Disaster Prevention Langfang 065200China College of Earth Sciences Jilin UniversityChangchun 130000China School of Earth Science and resources Chang'an UniversityXi'an 710000China School of resources and Civil Engineering Northeastern UniversityShenyang 110031China School of prospecting&Surveying Engineering Changchun Institute of TechnologyChangchun 130000China

The Daheishan supergiant porphyry molybdenum deposit(also referred to as the Daheishan deposit)is the second largest molybdenum deposit in Asia and ranks fifth among the top seven molybdenum deposits globally with total molybdenum reserves of 1.65 billion tons,an average molybdenum ore grade of 0.081%,and molybdenum resources of 1.09 million *** main ore body is housed in the granodiorite porphyry plutons and their surrounding inequigranular granodiorite plutons,with high-grade ores largely located in the ore-bearing granodiorite porphyries in the middle-upper part of the porphyry ***,it appears as an ore pipe with a large upper part and a small lower part,measuring about 1700 m in length and width,extending for about 500 m vertically,and covering an area of 2.3.km^(2).Mineralogically,the main ore body consists of molybdenite,chalcopyrite,and sphalerite horizontally from its center outward and exhibits molybdenite,azurite,and pyrite vertically from top to *** primary ore minerals include pyrite and molybdenite,and the secondary ore minerals include sphalerite,chalcopyrite,tetrahedrite,and scheelite,with average grades of molybdenum,copper,sulfur,gallium,and rhenium being 0.081%,0.03.%,1.67%,0.001%,and 0.0012%,*** ore-forming fluids of the Daheishan deposit originated as the CO_(2)-H_(2)O-NaCl multiphase magmatic fluid system,rich in CO_(2)and bearing minor amounts of CH4,N2,and H2S,and later mixed with meteoric *** various mineralization stages,the ore-forming fluids had homogenization temperatures of>420℃‒400℃,3.0℃‒3.0℃,3.0℃‒23.℃,220℃‒210℃,and 180℃‒160℃and salinities of>41.05%‒9.8%NaCleqv,3..16%‒4.48%NaCleqv,3..78%‒4.49%NaCleqv,7.43.NaCleqv,and 7.8%‒9.5%NaCleqv,*** mineralization of the Daheishan deposit occurred at 186‒167 *** granites closely related to the mineralization include granodiorites(granodiorite porphyries)and monzogranites(monzogranite porphyries),which were mineralized after magma

关键词： Molybdenum deposit Porphyry type Granodiorite porphyry Crust-mantle mixing Metallization U-Pb age O-S-Pb isotope Re isotope Inclusion type Ore-bearing fluid Metallogenic model prospecting model Mineral exploration engineering

Mechanical properties and energy evolution of jointed rock specimens containing an opening under uniaxial loading

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International Journal of Minerals,Metallurgy and Materials 2021年第12期28卷 1875-1886页

作者： Peng Li Mei-feng Cai Pei-tao Wang Qi-feng guo Sheng-jun Miao Fen-hua Ren School of Civil and resource Engineering University of Science and Technology BeijingBeijing 100083China key laboratory of High-Efficient Mining and Safety of Metal Mines(Ministry of Education of china) University of Science and Technology BeijingBeijing 100083China beijing key laboratory of Urban Underground Space Engineering University of Science and Technology BeijingBeijing 100083China

To investigate the impact of an opening and joints with different inclination angles on the mechanical response behavior,the energy evolution characteristics,and distribution law of granite specimens,uniaxial loading tests were performed on the parallel jointed rock samples with an *** indicated an initial decreasing trend of the strength and deformation parameters,which later increases with increased inclination angle,reaching minimum values when the inclination angle is 45°.Evolution curves of the elastic strain energy and dissipated energy with strain of the samples showed step-like gradual mutation *** peak total energy,peak elastic strain energy,peak dissipated energy,and total input energy during the failure of the samples showed significant nonlinear characteristics with increasing inclination *** opening and joints as well as the change of the inclination angle had significant influences on the proportion of the elastic strain energy of the samples prior to the peak,resulting in the difference of the distribution law of input ***,the energy mechanism of the sample failure was *** showed that the energy release was the internal cause of the sudden destruction of the entire rock mass.

关键词： deformation energy rock

One-step Synthesis of 5-Ethyl-2-methylpyridine from NH4HCO3.and C2H5OH Under Hydrothermal Condition

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Chemical Research in Chinese Universities 2015年第2期31卷 249-252页

作者： TIAN Zhenzhen ZHANG Dong guo Biao TIAN Ge LIU Xinxin yue Huijuan FENG Shouhua state key laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry key laboratory of Physics and Technology for Advance Batteries Ministry of Education College of Physics Jilin University Changchun 130012 P. R. China

A simple one-pot approach to synthesizing 5-ethyl-2-methylpyridine（EMP） was established using NHaHCO3.and C2H5OH as starting materials and commercial Cu2O as catalyst and oxidant under hydrothermal con- dition. Different reaction conditions were researched and the optimal ones were achieved by studying the parameters, that could affect the yield of product and by considering the energy and resource saving. The present study provided an eco-friendlv way to obtaining EMP with lower volatility using fewer toxic starting materials.

关键词： 5-Ethyl-2-methylpyridine Hydrothermal condition NH4HCO3 C2H5OH CU2O

Comparative Transcriptome Analysis Reveals Different Mechanisms of Adaptation to Environment among Three Species of Saussurea DC.

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Phyton-International Journal of Experimental Botany 2022年第7期91卷 1517-1528页

作者： Weimin Zhao Fengzhen Li guomin Shi Jialei guo Guifang He tao He School of Ecol-Environmental Engineering Qinghai UniversityXining810016China state key laboratory of Plateau Ecology and Agriculture Qinghai UniversityXining810016China key laboratory of Landscape Plants of Qinghai Province Qinghai UniversityXining810016China

Saussurea medusa,Saussurea hypsipeta and Saussurea obvallata are typical alpine snowline plants growing in the Qinghai-Tibet *** are characterized by a specialized *** and *** have very dense trichomes on whole plant,whereas *** has transparent bracts covered *** different forms reflect their adaptation to cold *** investigate the different mechanisms of adaptation of these species to cold temperatures,transcriptome sequencing was performed in three species of Saussurea DC.A total of 1163.413.23. and 113.79 Unigenes were identified from ***,*** and ***,*** these,55909(48.03.),65519(47.74%)and 51889(45.56%)Unigenes were matched in public *** analysis identified that most of annotated Unigenes in the three species of plants were related to cellular,metabolic,and single−organism processes,and binding and catalytic *** differential expression of 3. genes related to environmental adaptation were discovered by pairwise *** these,two candidate genes(Interaptin-like and CSLB3.related to trichome development were identified only in *** and ***,which was consistent with their distinct *** data can provide a valuable resource for the further studies on the adaptive mechanisms of molecular and functional ecology in Saussurea DC.

关键词： Saussurea DC. transcriptome adaptive mechanisms

基于杉楠近自然改造后的杉木直径分布模型研究

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林业科学研究 2024年第5期37卷 85-93页

作者：江怡航刘振华胡宇欣潘红林陈涵玥张建国张雄清林木资源高效生产全国重点实验室国家林业和草原局林木培育重点实验室中国林业科学研究院林业研究所北京100091 南京林业大学南方现代林业协同创新中心江苏南京210037 湖南省林业科学院湖南长沙410000

[目的]杉木闽楠近自然改造模式是当前我国杉木人工林近自然改造的主要技术模式。研究杉楠近自然改造后的杉木直径分布模型,可为精准预测近自然改造后的杉木材种出材量提供重要依据。[方法]以湖南郴州西山林场杉木闽楠近自然改造试验林... 详细信息

[目的]杉木闽楠近自然改造模式是当前我国杉木人工林近自然改造的主要技术模式。研究杉楠近自然改造后的杉木直径分布模型,可为精准预测近自然改造后的杉木材种出材量提供重要依据。[方法]以湖南郴州西山林场杉木闽楠近自然改造试验林为研究对象,利用Normal分布、Lognormal分布、Weibull分布和Gamma分布4种常用的概率密度函数模拟杉楠近自然改造后的杉木直径分布,并通过偏度和峰度分析了杉木直径分布的特点。[结果]研究发现相对于对照纯林模式,近自然改造增加了杉木大径级的株数占比,杉木平均直径与杉木直径分布的偏度正相关。根据各模式林分直径分布的卡方检验结果,Normal分布和Weibull分布拟合近自然改造下杉木直径分布效果较优。[结论]结合Weibull函数的适应性和灵活性的特点,Weibull分布可用于杉楠不同近自然改造模式下的杉木直径分布,研究结果对于精准预测近自然改造下杉木的材种出材量具有重要意义。

关键词：杉木闽楠近自然改造直径分布

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不同变异系数煤层应力场与瓦斯场规律的数值模拟研究

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西安科技大学学报 2024年第2期44卷 268-278页

作者：王峰刘强邱黎明刘勇徐九洲郭明功马涛张国雷永贵能源开发有限责任公司西秀分公司贵州安顺561001 北京科技大学土木与资源工程学院北京100083 河南理工大学瓦斯地质与瓦斯治理国家重点实验室培育基地河南焦作454000 平顶山天安煤业股份有限公司河南平顶山467100

为揭示煤层厚度变化对煤层突出危险性的影响,建立了煤层变形场和瓦斯场耦合模型,并基于高斯分布建立了不同煤层变异系数的煤层模型,揭示了不同变异系数下的煤层应力场和瓦斯场分布规律。结果表明:稳定煤层与非稳定煤层应力场差别显著,... 详细信息

为揭示煤层厚度变化对煤层突出危险性的影响,建立了煤层变形场和瓦斯场耦合模型,并基于高斯分布建立了不同煤层变异系数的煤层模型,揭示了不同变异系数下的煤层应力场和瓦斯场分布规律。结果表明:稳定煤层与非稳定煤层应力场差别显著,非稳定煤层在煤层较薄处产生了应力集中现象,向厚煤层区域掘进时呈线性减小;煤层较厚处稳定煤层的应力大于非稳定煤层,且随着煤层变异系数的增加进一步减小;不同变异系数煤层随着变异系数的增加应力逐渐增加,主应力的增长速率随着掘进距离的增加逐渐增加;煤层厚度变化导致了煤层受到顶板的水平应力作用,在煤层较薄处,顶板水平应力指向煤层,导致煤层较薄处产生了应力集中,在煤层较厚处,顶板水平应力背离煤层,导致煤层应力相比较薄处小,且瓦斯浓度大、渗透率小、构造煤发育较多,在扰动下容易发生突出。

关键词：煤与瓦斯突出煤层厚度煤层变异系数多物理场瓦斯压力

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Properties of a new type Al/Pb-0.3.Ag alloy composite anode for zinc electrowinning

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International Journal of Minerals,Metallurgy and Materials 2013年第10期20卷 986-993页

作者： Hai-tao Yang Huan-rong Liu Yong-chun Zhang Bu-ming Chen Zhong-cheng guo Rui-dong Xu Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology Faculty of Land resource Engineering Kunming University of Science and Technology Kunming Hendera Science and Technology Co.Ltd. state key laboratory Breeding Base of Complex Nonferrous Metal {3.s Cleaning Utilization

An A1/Pb-0.3.Ag alloy composite anode was produced via composite casting. Its electrocatalytic activity for the oxygen evolution reaction and corrosion resistance was evaluated by anodic polarization curves and accelerated corro- sion test, respectively. The microscopic morphologies of the anode section and anodic oxidation layer during accelerated corrosion test were obtained by scanning electron microscopy. It is found that the composite anode （hard anodizing） dis- plays a more compact interracial combination and a better adhesive strength than plating tin. Compared with industrial Pb-0.3.Ag anodes, the oxygen evolution overpotentials of A1/Pb-0.3.Ag alloy （hard anodizing） and A1/Pb-0.3.Ag alloy （plating tin） at 500 A.m-2 were lower by 57 and 14 mV, respectively. Furthermore, the corrosion rates of Pb-0.3.Ag alloy, A1/Pb-0.3.Ag alloy （hard anodizing）, and A1/Pb-0.3.Ag alloy （plating tin） were 13.977, 9.487, and 11.824 g.m-2.h-1, respectively, in accelerated corrosion test for 8 h at 2000 A-m-2. The anodic oxidation layer of A1/Pb-0.3.Ag alloy （hard anodizing） is more compact than Pb-0.3.Ag alloy and A1/Pb-0.3.Ag alloy （plating tin） after the test.

关键词： composite anodes corrosion resistance oxygen evolution reaction electrocatalytic activity zinc electrowin-ning