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澜沧县桉树引种对林下植物多样性及生境质量的影响研究

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云南大学学报（自然科学版） 2024年第2期46卷 345-354页

作者：周世杰赵筱青黄佩冯严董雯雯唐媛媛刘玉杰熊波云南大学地球科学学院云南昆明650500 云南大学国际河流与生态安全研究院云南昆明650500 云南省国土资源规划设计研究院云南昆明650200

外来树种桉树(Eucalyptus robusta Smith)的林下植物物种组成及多样性对区域生态系统功能有显著影响,桉树引种对林下植物多样性的影响一直存在争议,同时桉树引种对区域生境质量的影响尚不明晰.作者以典型桉树引种区云南省澜沧拉祜族自... 详细信息

外来树种桉树(Eucalyptus robusta Smith)的林下植物物种组成及多样性对区域生态系统功能有显著影响,桉树引种对林下植物多样性的影响一直存在争议,同时桉树引种对区域生境质量的影响尚不明晰.作者以典型桉树引种区云南省澜沧拉祜族自治县为研究区,运用空间代替时间及典型抽样法,分析成熟桉树人工林对林下植物多样性的影响;并基于物种多样性指数和NDVI修正InVEST模型参数,揭示成熟桉树人工林的生境质量特征.结果表明:(1)从整个群落看,桉树替代常绿阔叶林、思茅松林、灌木林后,成熟桉树人工林的林下植物多样性降低,所有对比样地的Sorensen指数低,且2/3的桉树林样地Shannon-Wiener指数较低;(2)低生境分布在北部和西部地区的建设用地、旱地、水田等区域,大面积的林地生境质量较高,其中常绿阔叶林、思茅松林、灌木林和成熟桉树人工林的生境质量均值分别为0.994 1、0.996 7、0.993 3、0.923 1,成熟桉树人工林的生境质量最低;(3)通过生态安全系数验证,修正生境适宜度参数后的InVEST模型,生境质量更具有科学性和合理性.

关键词：成熟桉树人工林林下植物多样性生境质量 InVEST模型参数修正澜沧

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大跨变高度组合钢箱连续梁桥空间效应分析

公路 2024年第8期69卷 71-76页

作者：周纪同郏亚坤李盘山苏秀丽陶延军王宇锋山东易方达建设项目管理有限公司济南市250000 上海市政工程设计研究总院(集团)有限公司上海市200092 济南城市建设集团有限公司济南市250000

不同于混凝土梁桥及钢箱梁桥,大跨变高度组合钢箱连续梁桥具有独特的空间受力特性。本研究以某大跨变高度组合钢箱连续梁桥为研究对象,建立空间有限元模型,从端横梁和中支点横梁的竖向剪力分配规律及偏载系数3个方面,探究其空间受力特... 详细信息

不同于混凝土梁桥及钢箱梁桥,大跨变高度组合钢箱连续梁桥具有独特的空间受力特性。本研究以某大跨变高度组合钢箱连续梁桥为研究对象,建立空间有限元模型,从端横梁和中支点横梁的竖向剪力分配规律及偏载系数3个方面,探究其空间受力特性。结果表明,组合钢箱梁端横梁处,顶板混凝土承受很小的竖向剪力,剪力主要由钢箱梁腹板承受;组合钢箱梁中支点横梁处,顶板混凝土承受很小的竖向剪力,剪力主要由底板混凝土和钢箱梁腹板承受,越靠近中支点横梁,底板混凝土承受竖向剪力所占比例越大,最大为45%;汽车偏载作用下,正应力偏载系数很小,腹板剪力偏载系数较大,支点处的剪力偏载系数最大可达1.76。研究结果对大跨组合钢箱梁桥的设计计算具有一定的指导意义。

关键词：桥梁工程组合钢箱连续梁空间效应剪力分配底板混凝土偏载系数

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Room-temperature coherent manipulation of single-spin qubits in silicon carbide with a high readout contrast

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National Science Review 2022年第5期9卷 89-98页

作者： Qiang Li Jun-feng Wang Fei-Fei Yan Ji-Yang zhou Han-feng Wang He Liu Li-Ping Guo Xiong zhou Adam Gali Zheng-Hao Liu Zu-Qing Wang Kai Sun Guo-Ping Guo Jian-Shun Tang Hao Li Li-Xing You Jin-Shi Xu Chuan-feng Li Guang-Can Guo CAS Key Laboratory of quantum Information University of Science and Technology of China CAS Center for Excellence in quantum Information and quantum Physics University of Science and Technology of China Key Laboratory of Artificial Micro-and Nano-structures of Ministry of Education and School of Physics and Technology Wuhan University Department of Atomic Physics Budapest University of Technology and Economics Wigner Research Centre for Physics State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences(CAS)

Spin defects in silicon carbide(SiC) with mature wafer-scale fabrication and micro/nano-processing technologies have recently drawn considerable *** room-temperature single-spin manipulation of colour centres in SiC has been demonstrated,the typically detected contrast is less than 2%,and the photon count rate is also ***,we present the coherent manipulation of single divacancy spins in 4 H-SiC with a high readout contrast(-30%) and a high photon count rate(150 kilo counts per second)under ambient conditions,which are competitive with the nitrogen-vacancy centres in *** between a single defect spin and a nearby nuclear spin is also *** further provide a theoretical explanation for the high readout contrast by analysing the defect levels and decay *** the high readout contrast is of utmost importance in many applications of quantum technologies,this work might open a new territory for SiC-based quantum devices with many advanced properties of the host material.

关键词： silicon carbide single divacancy defects spin coherent control high readout contrast bright photon emission

Low-complexity and high-performance receive beamforming for secure directional modulation networks against an eavesdropping-enabled full-duplex attacker

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Science China(Information Sciences) 2022年第1期65卷 290-291页

作者： Yin TENG Jiayu LI Mengxing HUANG Lin LIU Guiyang XIA Xiaobo zhou feng SHU Jiangzhou WANG School of Electronic and Optical Engineering Nanjing University of Science and Technology School of Information and Communication Engineering Hainan University School of Physics and Electronic Engineering Fuyang Normal University School of Engineering and Digital Arts University of Kent

Dear editor,Directional modulation(DM), as an advanced physical-layer security(PLS) transmission technique, is suitable for the line-of-sight(Lo S) propagation channel. In [1], the authors presented a DM technique that uses the phased arrays to generate modulation and provides security by deliberately distorting the received signals in other directions.

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Abandoned land identification in karst mountain area based on time series SAR characteristics at geo-parcels scale

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山地科学学报（英文） 2023年第3期20卷 792-809页

作者： zhou Zhong-fa WANG Ling-yu CHEN quan LUO Jian-cheng ZHAO Xin ZHANG Shu ZHANG Wen-hui LIAO Juan LYU Zhi-jun School of Karst Science Guizhou Normal UniversityGuiyang 550001China Key Laboratory of Natural Resources Monitoring in Tropical and Subtropical Area of South China Ministry of Natural ResourcesGuangzhou 510670China Department of Information Engineering Guizhou Institute of Light IndustryGuiyang 550001China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100101China Hengyang Normal University Hengyang 421000China

Mapping abandoned land is very important for accurate agricultural ***,in karst mountainous areas,continuous high-resolution optical images are difficult to obtain in rainy weather,and the land is fragmented,which poses a great challenge for remote sensing monitoring of agriculture *** this study,a new method for identifying abandoned land is proposed:firstly,a few Google Earth images are used to transform arable land into accurate vectorized geo-parcels;secondly,a time-series data set was constructed using Sentinel-1A Alpha parameters for 2020 on each farmland geoparcel;thirdly,the semi-variation function(SVF)was used to analyze the spatial-temporal characteristics,then identify abandoned *** results show:(1)On the basis of accurate spatial information and boundary of farmland land,the SAR time-series dataset reflects the structure and time-series *** land with an accuracy of 80.25%.The problem of remote sensing monitoring in rainy regions and complex surface areas is well-resolved.(2)The spatial heterogeneity of abandoned land is more obvious than that of cultivated land within *** step size for significant changes in the SVF of abandoned land is shorter than that of cultivated land.(3)The SVF time sequence curve presented a strong peak feature when farmland was *** reveals that the internal spatial structure of abandoned land is more disordered and *** showed that time-series variations of spatial structure within cultivated land have broader applications in remote sensing monitoring of agriculture in complex imaging environments.

关键词： Sentinel-1 SAR Abandoned farmland Semi variogram function Farmland geo parcel Time seriescharacteristics Texture feature Karst mountainous area

Phenolic glycosides from Boschniakia himalaica

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Chinese Chemical Letters 2012年第5期23卷 579-582页

作者： Jin Fu Wan Jing quan Yuan Zhi Nan Mei Xin zhou Yang Yunnan Baiyao Group Co.LTD Kunming 650032China College of Pharmacy South-Central University for NationalitiesWuhan 430074China Guangxi Institute of Medicinal Plants Nanning 530023China

Two new phenylethanoid glycosides,himalosides A（1） and B（2）,were isolated from the whole plant of Boschniakia himalaica, together with four known *** structures were elucidated on the basis of spectral and chemical *** A（1） and（＋）-lariciresinol 4＇-O-β-D-glucopyranoside（4） exhibited antibacterial activity with the MIC values at 50 and 25μg/mL against Staphylococcus aureus and ***,respectively.

关键词： Boschniakia himalaica Phenylethanoids Phenolic glycosides Antibacterial

A proteome-wide screen identifies valosin-containing protein as an essential regulator of podocyte endoplasmic reticulum stress

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Chinese Science Bulletin 2012年第20期57卷 2493-2505页

作者： HUANG ZhiYong HONG quan XUE Peng PAUL Goulding feng Zhe WANG LiYuan MEI Yan WU LingLing CHEN XiangMei WU Di State Key Laboratory of Kidney Disease(2011DAV00088) Kidney Department&Institute of NephrologyDivision of Clinical Internal MedicineChinese People’s Liberation Army General HospitalBeijing 100853China Laboratory of Proteomics Institute of BiophysicsChinese Academy of SciencesBeijing 100101China Nonlinear Dynamics Ltd Keel HouseGarth HeadsNewcastle upon TyneNE12JEUK

To investigate proteins expressed in the renal tissue of the passive Heymann nephritis (pHN) rat model,we prepared pHN rat models with anti-FxA1 serum and analyzed the proteins differentially expressed in the kidney tissue with label-free liquid chromatography-tandem mass *** then analyzed in depth the endoplasmic reticulum stress (ERS)-related protein using an online bioinformatics ***-one differential proteins and their annotations were *** Ontology (GO) function analysis showed that 16 proteins were involved in cellular metabolism and 22 were proteins related to catalytic activity,including protein folding or ***-GO networks indicated that VCP could interact with the ERS marker HSPa5,with both involved in a single *** inhibition of podocyte VCP by RNAi under normal conditions,the HSPa5 expression level did not change,but when the cell was subjected to ERS by tunicamycin,HSPa5 expression significantly increased with RNAi of VCP when compared with the tunicamycin-treated *** results showed that ERS plays an important role in podocyte injury of membranous nephropathy and is mediated by an HSPa5-VCP signaling pathway,in which the most predominant proteins are those related to cellular metabolism and catalytic activity.

关键词：蛋白质折叠内质网应激细胞损伤 Networks公司宽屏幕标识大鼠模型催化活性

Intelligent droplet tracking with correlation filters for digital microfluidics

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Chinese Chemical Letters 2021年第11期32卷 3416-3420页

作者： Libin Li Zhen Gu Jia-Le zhou Bingyong Yan Cong Kong Hua Wang Hui-feng Wang Key Laboratory of Advanced Control and Optimization for Chemical Processes Ministry of Education East China University of Science and TechnologyShanghai 200237China Key Laboratory of East China Sea Fishery Resources Exploitation Ministry of Agriculture and Rural AffairsEast China Sea Fisheries Research InstituteChinese Academy of Fishery SciencesShanghai 200090China Department of Laboratory Medicine Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200137China

Tracking the movement of droplets in digital microfluidics is essential to improve its control stability and obtain dynamic information for its applications such as point-of-care testing,environment monitoring and chemical ***,an intelligent,accurate and fast droplet tracking method based on machine vision is developed for applications of digital *** continuously recognize the transparent droplets in real-time and avoid the interferes from background patterns or inhomogeneous illumination,we introduced the correlation filter tracker,enabling online learning of the multi-features of the droplets in Fourier *** show the proposed droplet tracking method could accurately locate the *** also demonstrated the capacity of the proposed method for estimation of the droplet velocity as faster as 20 mm/s,and its application in online monitoring the Griess reaction for both colorimetric assay of nitrite and study of reaction kinetics.

关键词： Digital microfluidics Correlation filter trackers Machine vision Reaction kinetics Colorimetric assay

秦巴山区生态系统服务对植被覆盖变化的响应阈值

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生态学报 2024年第15期44卷 6811-6827页

作者：王晓峰白娟冯晓明周继涛王筱雪尧文洁涂又孙泽冲马嘉豪长安大学土地工程学院西安710054 陕西省土地整治重点实验室西安710054 长安大学地质工程与测绘学院西安710054 中国科学院生态环境研究中心城市与区域生态国家重点实验室北京100085

秦巴山区地处我国南北气候、生物区系的交汇地带,具有十分重要的地理与生态价值,蕴藏着巨大的发展潜力。确定生态系统服务对植被覆盖变化的响应阈值是实现秦巴山区环境资源有效配置、管理政策科学制定以及生态效益最大化的重要前提。在... 详细信息

秦巴山区地处我国南北气候、生物区系的交汇地带,具有十分重要的地理与生态价值,蕴藏着巨大的发展潜力。确定生态系统服务对植被覆盖变化的响应阈值是实现秦巴山区环境资源有效配置、管理政策科学制定以及生态效益最大化的重要前提。在分析秦巴山区产水、固碳、土壤保持和生境质量4项生态系统服务时空特征的基础上,综合运用聚类分析、方差分析和弹性分析对比不同植被类型和地形梯度下生态系统服务的异同进而分区计算植被覆盖变化的影响阈值。结果表明:(1)2000—2020年,产水、固碳、土壤保持和生境质量服务整体提升且均表现为东南高西北低的空间分布。(2)不同类型植被下,生态系统服务整体供应能力从大到小依次为林地、草地和农田。不同地形变化下,除生境质量呈持续增长态势外,其他3项服务均出现了先提高后衰减的非线性趋势。(3)植被覆盖度对生态系统服务有促进作用,但超过一定阈值后这种作用会逐渐减弱。植被覆盖影响阈值在林地、草地和农田区分别为0.85、0.80和0.78;且该阈值随地形因子增加先增大后减小。本研究结果可以转变秦巴山区单纯依靠扩大森林面积提升生态系统服务供给的简单化生态保护模式,为构建分区管理、全面系统和动态平衡的生态可持续发展体系提供依据。

关键词：生态系统服务植被覆盖变化阈值植被类型地形梯度