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Overstory functional groups indicate the legacy of land use in a secondary tropical forest in southwestern China

Journal of Forestry Research 2024年第5期35卷 91-105页

作者： Yun Deng Wenfu Zhang Min Cao jinlong dong Hui Chen Xiaobao Deng Jiajia Liu Xiaoyang Song Shangwen Xia Liqing Sha Shengdong Yuan Luxiang Lin CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303People’s Republic of China Center for Plant Ecology Core Botanical GardensChinese Academy of SciencesMengla 666303People’s Republic of China National Forest Ecosystem Research Station at Xishuangbanna Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303People’s Republic of China Department of Life Sciences Fudan UniversityShanghai 570228People’s Republic of China Department of Life Sciences University of Chinese Academy of SciencesBeijing 100049People’s Republic of China

Anthropogenic disturbances are widespread in tropical forests and influence the species composition in the ***,the impacts of historical disturbance on tropical forest overstory recovery are unclear due to a lack of disturbance data,and previous studies have focused on understory *** this study,the purpose was to deter-mine the influence of historical disturbance on the diver-sity,composition and regeneration of overstory species in present *** the 20-ha Xishuangbanna tropical sea-sonal rainforest dynamics plot in southwestern China,the historical disturbance boundaries were delineated based on panchromatic photographs from *** that drove species clustering in the overstory layer(DBH≥40 cm)were analyzed and the abundance,richness and composition of these species were compared among different tree groups based on multiple regression tree *** coefficient of variation of the brightness value in historical panchro-matic photographs from 1965 was the primary driver of spe-cies clustering in the overstory *** abundance and richness of overstory species throughout the regeneration process were similar,but species composition was always *** the proportion of large-seeded and vigorous-sprouting species showed no significant differ-ence between disturbed and undisturbed forests in the tree-let layer(DBH<20 cm),the difference became significant when DBH *** findings highlight that historical disturbances have strong legacy effects on functional group composition in the overstory and the recovery of overstory species was *** group composi-tion can better indicate the dynamics of overstory species replacement during secondary succession.

关键词： Historical disturbance Legacy effects Secondary forests Overstory species Functional groups

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改进生成对抗网络的雾霾天气交通标志识别算法

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重庆理工大学学报（自然科学） 2024年第6期38卷 203-211页

作者：董金龙贾志绚太原科技大学车辆与交通学院太原030024

为提高雾霾天气下交通标志识别的准确性,提出一种改进生成对抗网络(GAN)的雾霾天气交通标志识别算法。该算法主要分为2个部分:第1部分是多尺度GAN的图像去雾,在生成器中增加多尺度卷积和感知损失函数,多尺度卷积有利于提取特征,感知损... 详细信息

为提高雾霾天气下交通标志识别的准确性,提出一种改进生成对抗网络(GAN)的雾霾天气交通标志识别算法。该算法主要分为2个部分:第1部分是多尺度GAN的图像去雾,在生成器中增加多尺度卷积和感知损失函数,多尺度卷积有利于提取特征,感知损失可以在图像的深度特征上保留内容、风格等高级语义信息,使去雾效果更符合人眼对图像质量的感受;第2部分是交通标志识别,在原有YOLOX-S模型的基础上增加感受野更小的160×160检测层来降低小尺度交通标志的漏检率,其次在主干网络中增加坐标注意力(CA)机制强化特征网络。实验结果表明,提出的去雾模型具有较好的效果,评价指标PSNR和SSIM的结果都优于其他代表性算法;交通标志识别算法与原模型进行比较,准确率、mAP值、召回率分别提高了2%、4%和7%,验证了模型的有效性。

关键词：多尺度卷积交通标志感知损失 YOLOX 注意力机制

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Nitrogen slow-release behavior of oxamide granules in two different types of paddy soils

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Pedosphere 2022年第6期32卷 856-865页

作者： Xun LI jinlong dong Jingjing DUAN Wenzhong SHEN Zengqiang DUAN State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) School of the Environment and Safety Engineering Jiangsu UniversityZhenjiang 212013(China) Agricultural Technology Promotion Center Taicang Agriculture CommitteeSuzhou 215400(China)

Oxamide is a potential slow-release nitrogen(N)fertilizer,especially under waterlogged conditions,due to its low solubility in water and the slow-release of ammonium by soil *** investigate the effects of oxamide granules(2.00-2.38 mm in diameter)as a single basal fertilizer(180 or 144 kg N ha^(-1))on rice growth,soil properties,and N use efficiency in terms of N recovery efficiency(NRE),we conducted field experiments on two different types of paddy soils over two rice-growing *** showed that the fertilization effects of oxamide granules varied between the two types of paddy *** the red clayey paddy soil,the grain yields for both rice-growing seasons were high with a significantly higher NRE in the oxamide treatment than in the urea ***,in the alluvial sandy paddy soil,the grain yields in the oxamide treatment were slightly lower than those in the urea ***,oxamide produced little improvement in NRE in the alluvial sandy paddy *** incubation experiments over 98 d were also carried out to evaluate the factors affecting the N release behavior of oxamide granules in the two types of paddy *** found that the amidase activity was higher and,therefore,the oxamide hydrolysis rate was faster in the alluvial sandy paddy soil,which had a higher soil pH value and organic matter content,compared to the red clayey paddy *** faster N release and the longer growth period resulted in a mismatch between N supply by oxamide and rice demand,which,in turn,led to little improvement in NRE and a decreased grain yield in the alluvial sandy paddy soil,especially in the reduced oxamide *** results could help select the appropriate size of oxamide granules for use as a slow-release N fertilizer depending on the soil properties and growth period of rice.

关键词： amidase activity grain yield nitrogen use efficiency organic matter content pH slow-release fertilizer

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First discovery of coesite in eclogite from East Kunlun, northwest China

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Science Bulletin 2018年第23期63卷 1536-1538页

作者： Hengzhe Bi Shuguang Song jinlong dong Liming Yang Shengsheng Qi Mark B.Allen MOE Key Laboratory of Orogenic Belt and Crustal Evolution School of Earth and Space SciencesPeking UniversityBeijing 100871China Qinghai Bureau of Geological Survey Xining 810012China Department of Earth Sciences Durham UniversityDurham DH13LEUK

Ultrahigh-pressure (UHP)metamorphism plays important roles in continental *** of this process has been enhanced by the discovery of coesite and micro-diamond from supracrustal rocks [1].Such UHP mineral inclusions provide unequivocal evidence that the least dense part of the lithosphere can be buried to 100-150km or more,and then returned to the ***,an ultrahigh-pressure polymorph of SiO2stable above 2.7GPa at metamorphic temperatures,is one of the most important index minerals for UHP metamomhism [1,2].

关键词： Cobalt feldspar East Kunlun eclogite

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Current Researches on Blocks in North Great Xing'an Range and Its Geological Significance

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Journal of Landscape Research 2014年第4期6卷 25-26,30页

作者： dong jinlong dong Jinyuan YANG Zhenjun College of Geosciences and Resources China University of Geosciences Gansu Seismological Bureau Beijing Institute of Geology for Mineral Resources Beijing Donia Resources Co. Ltd.

Boundary properties,collage and collision time of Erguna and Xing'an block,and old crystal substrate of the blocks are basic geological scientific issues for studying the evolution of north Great Xing'an *** study reviewed researches on Erguna and Xing'an block in the past years,and summarized two major problems: one is collage and collision time of both blocks; the other is ancient crystal substrate of the *** two problems are significant for understanding tectonic-magma evolution of the north Great Xing'an Range.

关键词： Blocks Boundary Collage and collision Time Crystal substrate

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Passive daytime radiative cooling coatings with renewable self-cleaning functions

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Chinese Chemical Letters 2024年第2期35卷 257-262页

作者： Qian Wu Yubo Cui Guifeng Xia jinlong Yang Shuming Du Xinhong Xiong Li Yang dong Xu Xu Deng Jiaxi Cui Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China Yangtze Delta Region Institute (Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China Beijing Key Laboratory of Power Generation System Functional Material CHN Energy New Energy Technology Research Institute Ltd.Beijing 102209China Institute for Advanced Study Chengdu UniversityChengdu 610106China

Passive daytime radiative cooling(PDRC)technology is emerging as one of the most promising solutions to the global problem of spacing cooling,but its practical application is limited due to reduced cooling effectiveness caused by daily wear and tear,as well as dirt *** tackle this problem,we report a novel strategy by introducing a renewable armor structure for prolonging the anti-fouling and cooling effectiveness properties of the PDRC *** armor structure is designed by decorating fluorinated hollow glass microspheres(HGM)inside rigid resin composite *** HGM serve triple purposes,including providing isolated cavities for enhanced solar reflectance,reinforcing the matrices to form robust armored structures,and increasing thermal *** the coatings are worn,the HGM on the surface expose their concave cavities with numerous hydrophobic fragments,generating a highly rough surface that guarantee the superhydrophobic *** coatings show a high sunlight reflectance(0.93)and thermal emittance(0.94)in the long-wave infrared window,leading to a cooling of 5℃ below ambient temperature under high solar flux(∼900 W/m^(2)).When anti-fouling functions are reduced,they can be regenerated more than 100 cycles without compromising the PDRC function by simple wearing ***,these coatings can be easily prepared using a one-pot spray method with low-cost materials,exhibit strong adhesion to a variety of substrates,and demonstrate exceptional environmental ***,we anticipate their immediate application opportunities for spacing cooling.

关键词： Superhydrophobic Passive radiative cooling Wearing Regeneration Glass resin armor

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红心莲毁灭炭疽病菌生物学特性及高效安全药剂筛选

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福建农业学报 2022年第8期37卷 1067-1071页

作者：董金龙长泰金诺农业科技有限公司福建漳州363902

【目的】明确红心莲炭疽病菌毁灭炭疽菌(Colletotrichum destructivum)的生物学特性。测定不同化学结构和作用机制的6种杀菌剂对毁灭炭疽菌的室内毒力,筛选高效安全杀菌剂。【方法】采用菌丝生长速率法测定温度、pH、光周期和碳、氮源... 详细信息

【目的】明确红心莲炭疽病菌毁灭炭疽菌(Colletotrichum destructivum)的生物学特性。测定不同化学结构和作用机制的6种杀菌剂对毁灭炭疽菌的室内毒力,筛选高效安全杀菌剂。【方法】采用菌丝生长速率法测定温度、pH、光周期和碳、氮源对菌丝生长的影响,以及6种杀菌剂对毁灭炭疽菌抑制效果。【结果】毁灭炭疽菌菌丝生长最适温度为30℃、最适pH为8,光周期对菌丝生长影响小,最适碳、氮源分别为淀粉和酵母。室内毒力测定结果表明,所选的6种杀菌剂对病原菌毒力差异大,其中咯菌腈的毒力最强,EC50为0.0236 mg·L^(-1);其次为咪鲜胺和吡唑醚菌酯,EC50分别为0.0306和0.0487 mg·L^(-1);甲基硫菌灵和苯醚甲环唑的毒力较弱,EC50分别为0.1526和0.1955 mg·L^(-1);多菌灵的毒力最弱,EC50为0.2199 mg·L^(-1)。【结论】温度、pH、碳氮源对毁灭炭疽菌菌丝生长具有一定影响。咯菌腈、咪鲜胺和吡唑醚菌酯等杀菌剂对毁灭炭疽菌有较好的室内毒力。

关键词：红心莲毁灭炭疽菌生物学特性药剂毒力测定

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GH4169晶粒尺寸的双目标超声评价方法

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航空动力学报 2021年第4期36卷 816-825页

作者：陈曦董金龙陈昊黎明彭思琴南昌航空大学无损检测技术教育部重点实验室南昌330063 南昌航空大学信息工程学院南昌330063

针对仅以评价准确性为目标的多超声评价方法易失去单调可评价性这一问题,同时以准确性、单调性为优化目标,提出一种面向GH4169晶粒尺寸的双目标多超声参数评价方法。根据相关性准则选取多超声参数,并构建二次多项式评价关系模型;以平均... 详细信息

针对仅以评价准确性为目标的多超声评价方法易失去单调可评价性这一问题,同时以准确性、单调性为优化目标,提出一种面向GH4169晶粒尺寸的双目标多超声参数评价方法。根据相关性准则选取多超声参数,并构建二次多项式评价关系模型;以平均绝对误差为准确性评价目标,以斯皮尔曼相关系数为单调性评价目标,构建以评价模型待定参数为决策变量的双目标优化问题,并利用多目标优化算法求解获得最终的超声评价模型。结果表明:该方法所确定的模型的偏差与相对误差分别为3.05%与10.69%,这表明其准确度及稳定性均显著优于其他模型。

关键词： GH4169合金晶粒尺寸超声评价多目标优化多参数

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大兴安岭牙克石地区新元古代与晚古生代两类岩石组合的构造属性及其地质意义

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岩石学报 2018年第6期34卷 1758-1774页

作者：董金龙白志达徐德兵罗志波北京大学地球与空间科学学院教育部造山带与地壳演化重点实验室北京100871 中国地质大学(北京)地球科学与资源学院北京100083 天津市地球物理勘探中心天津300170

在内蒙牙克石地区发育两种不同构造属性的岩石组合:一类为乌奴耳-头道桥蛇绿混杂岩,另一类为晚古生代弧属性侵入岩。乌奴耳-头道桥蛇绿混杂岩由辉长岩、辉长辉绿岩、辉绿玢岩(岩墙?)、变玄武岩和放射虫硅质岩组成;地球化学特征显示基性... 详细信息

在内蒙牙克石地区发育两种不同构造属性的岩石组合:一类为乌奴耳-头道桥蛇绿混杂岩,另一类为晚古生代弧属性侵入岩。乌奴耳-头道桥蛇绿混杂岩由辉长岩、辉长辉绿岩、辉绿玢岩(岩墙?)、变玄武岩和放射虫硅质岩组成;地球化学特征显示基性岩类属于拉斑玄武岩系列,具有相似的稀土和原始地幔标准化配分模式,与N-MORB的特征类似,不具有Nb-Ta负异常,Nb/Nb~*值平均>1;构造环境判别图显示该蛇绿混杂岩可能形成于扩张脊。晚古生代弧属性侵入岩出露于白井山、乌尔其汗,由中基性单元(辉长岩、辉长闪长岩和石英闪长岩)和酸性单元(花岗闪长岩和二长花岗岩)组成;地球化学特征显示中基性单元和酸性单元属于钙碱性岩系列,富集LREEs和LILEs,具有Nb-Ta负异常,高Sr、Sr/Y值,低HREEs和Y,Eu异常不明显;酸性单元显示埃达克质岩的地球化学特征。乌奴耳-头道桥蛇绿混杂岩可能形成于新元古代,与头道桥蓝片岩、吉峰蛇绿混杂岩、新林蛇绿岩构成一条重要的缝合带,暗示本区古洋盆的存在。晚古生代弧属性侵入岩中,辉长岩的结晶年龄为326±1.9Ma,花岗闪长岩的结晶年龄为323.7±1.9Ma;微量元素的组成特征显示,中基性单元和酸性单元的形成与早石炭世洋壳板片的俯冲作用有关,暗示兴安地块和松嫩地块之间洋盆的萎缩。

关键词：蛇绿混杂岩扩张脊弧属性新元古代晚古生代牙克石地区

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GH4169晶粒尺寸的多参数超声评价方法

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机械工程学报 2018年第24期54卷 18-26页

作者：陈昊董金龙陈曦邬冠华周正干南昌航空大学无损检测技术教育部重点实验室南昌330063 北京航空航天大学机械工程及自动化学院北京100191

考虑到单个超声响应特性参数反应出晶粒尺寸的特征信息不够全面,提出将多个超声参数相结合,构建面向GH4169晶粒尺寸无损定量表征的多参数超声评价方法。依据相关性度量准则,从声速、衰减系数、非线性系数等8个超声参数中选取有效参数;... 详细信息

考虑到单个超声响应特性参数反应出晶粒尺寸的特征信息不够全面,提出将多个超声参数相结合,构建面向GH4169晶粒尺寸无损定量表征的多参数超声评价方法。依据相关性度量准则,从声速、衰减系数、非线性系数等8个超声参数中选取有效参数;构建二次多项式的映射模型,将选取的多维参数降成单维参数并进行量纲一化处理;在对单维参数与晶粒尺寸拟合过程中,构建以两者平均绝对误差最小为目标的优化问题并结合进化算法进行求解,寻找最佳的映射函数和拟合函数系数;最终建立多参数超声评价模型。经测试样本验证表明,与单一参数的声速法模型、衰减系数法模型和背散射EMD法模型相比,所建模型评价结果精度高,性能稳定、误差小且有着良好的评价效应;融合了多个超声检测参数而保留了对晶粒尺寸的响应信息,提高了测量精度和抗干扰能力。

关键词：多参数映射模型超声评价晶粒尺寸进化算法

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