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长沙市城市公园植物景观分析

绿色科技 2019年第1期21卷 132-134页

作者：陈梦洁李炎林吕长平孙田娇湖南农业大学园艺园林学院湖南长沙410128 湖南省中亚热带优质花木繁育与利用工程技术中心湖南长沙410128

通过对长沙市3个公园实地调查,针对植物种类和配置现状进行了分析,调研发现:长沙市城市公园植物景观整体协调,季相变化明显,观赏效果佳,植物群落景观层次丰富,但存在部分配置对植物长久生长不利,单一植物配置过多,植物色彩搭配单调,水... 详细信息

通过对长沙市3个公园实地调查,针对植物种类和配置现状进行了分析,调研发现:长沙市城市公园植物景观整体协调,季相变化明显,观赏效果佳,植物群落景观层次丰富,但存在部分配置对植物长久生长不利,单一植物配置过多,植物色彩搭配单调,水生植物景观不足等问题,针对这些问题提出了相应的解决办法,期望能为以后长沙市城市公园的建设提供参考。

关键词：城市公园长沙市植物配置

Spatio-temporal Convolutional Network Based Power Forecasting of Multiple Wind Farms

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Journal of Modern Power Systems and Clean Energy 2022年第2期10卷 388-398页

作者： Xiaochong Dong Yingyun sun Ye Li Xinying Wang tianjiao Pu the School of Electrical and Electronic Engineering North China Electric Power UniversityBeijing 102206China he China Electric Power Research Institute Beijing 100192China

The rapidly increasing wind power penetration presents new challenges to the operation of power *** the accuracy of wind power forecasting is a possible solution under this *** the power forecasting of mul-tiple wind farms,determining the spatio-temporal correlation of multiple wind farms is critical for improving the forecasting *** paper proposes a spatio-temporal convolutional network(STCN)that utilizes a directed graph convolutional structure.A temporal convolutional network is also adopted to characterize the temporal features of wind *** data from 15 wind farms in Australia are used in the case *** forecasting results show that the proposed model has higher accuracy than the existing *** on the structure of the STCN,asymmetric spatial correlation at different temporal scales can be observed,which shows the effectiveness of the proposed model.

关键词： Deep learning spatio-temporal correlation wind power forecasting graph conventional network(GCN).

9份湖南本土牡丹资源的形态学和ISSR分子标记分析

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分子植物育种 2020年第15期18卷 5038-5045页

作者：许文婷吕长平孙田娇陈梦洁秧拯民陈海霞李炎林湖南农业大学园艺学院长沙410128 湖南农业大学湖南省中亚热带优质花木繁育与利用工程技术研究中心长沙410128

本研究利用形态学指标和ISSR分子标记对9份湖南本土牡丹资源进行亲缘关系分析,根据9份湖南本土牡丹资源的22个主要性状的形态学聚类分析,Q型聚类分析的结果表明:9份湖南本土牡丹资源分成两大类:第一大类为‘凤优4号’、‘凤丹白’、‘... 详细信息

本研究利用形态学指标和ISSR分子标记对9份湖南本土牡丹资源进行亲缘关系分析,根据9份湖南本土牡丹资源的22个主要性状的形态学聚类分析,Q型聚类分析的结果表明:9份湖南本土牡丹资源分成两大类:第一大类为‘凤优4号’、‘凤丹白’、‘凤丹粉’、‘杨山牡丹’、‘宝庆红’、‘凤优2号’;第二大类为‘凤优1号’、‘凤优3号’、‘凤优5号’;ISSR分子标记分析的结果表明:用13条引物共进行扩增出223条谱带,其中多态性条带213条,多态性比例95.2%,通过NTSYS2.1进行聚类分析,在遗传相似性系数为0.54时,9份湖南本土牡丹资源可分为两大类,第1大类包括‘宝庆红’和‘凤优5号’;第2大类包括‘杨山牡丹’、‘凤丹白’、‘凤丹粉’、‘凤优1号’、‘凤优2号’、‘凤优3号’和‘凤优4号’。ISSR分子标记的遗传聚类分析结果与形态学的遗传聚类分析结果有一定的差异。综合以上,可为湖南本土牡丹种质资源开发利用和耐湿热的新品种育种奠定基础。

关键词：牡丹形态学标记 R型聚类主成分分析 Q型聚类

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一例菌落总数测量审核的回顾与分析

食品安全导刊 2024年第18期 54-56页

作者：孙天娇杨洪银张伟莹丁淑颖尹延柏济宁市质量计量检验检测研究院(济宁半导体及显示产品质量监督检验中心、济宁市纤维质量监测中心) 山东济宁272000 济宁市食品药品检验检测研究院山东济宁272000

目的:借助测量审核提高本实验室检测水平和核心竞争力。方法:以中国检验检疫科学研究院测试评价中心提供的作业指导书为依据,采用平板计数法和测试片法分别对样品进行检测。结果:配对t检验显示两种方法的检测结果不具有显著性差异(P> 0.... 详细信息

目的:借助测量审核提高本实验室检测水平和核心竞争力。方法:以中国检验检疫科学研究院测试评价中心提供的作业指导书为依据,采用平板计数法和测试片法分别对样品进行检测。结果:配对t检验显示两种方法的检测结果不具有显著性差异(P> 0.05),两种方法的|Z|值均小于2,为满意结果。结论:平板计数法和测试片法均可用于菌落总数的检测,检测机构可以依据自身条件选择合适的方法来检测样品中的菌落总数。

关键词：菌落总数测量审核测试片

Random Vibration Analysis of Urban Underground Tunnels Under Vertical Earthquake Excitations Based on Mass–Damper–Spring Model

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Transactions of Tianjin University 2018年第3期24卷 290-300页

作者： Haitao Zhu tianjiao Tang Puyang Zhang Jianqiao sun School of Civil Engineering Tianjin University Key Laboratory of Coast Civil Structure Safety of Ministry of Education Tianjin University School of Engineering University of CaliforniaMerced

In this paper, the verticalseismic effects on tunnels are studied based on a classic mass–damper–spring model. An analyticaldiscrete modelof urban underground tunnels subjected to verticalearthquake excitations is proposed by considering the first verticalvibration mode. Taking a light railproject in Tianjin as an example, this study uses the proposed discrete modelto analyze the displacements of tunneland soilunder verticalearthquake excitations. The soildisplacement responses at different tunnellocations are analyzed with linear random vibration *** computationalcost is greatly reduced using the proposed model. It can be seen that different from the case of horizontalearthquakes, the displacement responses under verticalearthquake excitations keep growing after seismic acceleration reaches its peak for a short duration, and then,they begin to decay. The soils at different positions around the tunnels have large relative displacement under verticalearthquake excitations. Moreover, a finite-element modelis also established for displacement responses using *** comparison with the results of the finite-element modelshows that the results of the proposed discrete modelare available.

关键词： Underground tunnel Vertical seismic action Mass-damper-spring model Random vibration

Temporal and spatial changes of microbial community in an industrial effluent receiving area in Hangzhou Bay

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Journal of Environmental Sciences 2016年第6期28卷 57-68页

作者： Yan Zhang Lujun Chen Renhua sun tianjiao Dai Jinping Tian Wei Zheng Donghui Wen School of Environment Tsinghua University Beijing 100084 China College of Environmental Sciences and Engineering Peking University Belting 100871 China Zhejiang Provincial Key Laboratory of Water Science and Technology Department of Environmental Technology and Ecology Yangtze Delta Region Institute of Tsinghua University Zhejiang Jiaxing 314050 China Zhejiang Shuangyi Eauironmental Technology Develoioment Co. Ltd. Jiaxing 314000 China Rural Energy & Environment Agency Ministry of Agriculture Beijing 100125 China

Anthropogenic activities usually contaminate water environments, and have led to the eutrophication of many estuaries and shifts in microbial communities. In this study, the temporal and spatial changes of the microbial community in an industrial effluent receiving area in Hangzhou Bay were investigated by 454 pyrosequencing. The bacterial community showed higher richness and biodiversity than the archaeal community in all sediments. Proteobacteria dominated in the bacterial communities of all the samples; MarineGroupⅠand Methanomicrobia were the two dominant archaeal classes in the effluent receiving area. PCoA and AMOVA revealed strong seasonal but minor spatial changes in both bacterial and archaeal communities in the sediments. The seasonal changes of the bacterial community were less significant than those of the archaeal community, which mainly consisted of fluctuations in abundance of a large proportion of longstanding species rather than the appearance and disappearance of major archaeal species. Temperature was found to positively correlate with the dominant bacteria, Betaproteobacteria, and negatively correlate with the dominant archaea,MarineGroupⅠ; and might be the primary driving force for the seasonal variation of the microbial community.

关键词： Bacterial community Archaeal community 454 pyrosequencing Effluent receiving area Sediment Hangzhou Bay

Nanostructured Ni/Ti3C2Tx MXene hybrid as cathode for lithium-oxygen battery

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Chinese Chemical Letters 2020年第4期31卷 1000-1003页

作者： Caiying Wen tianjiao Zhu Xingyu Li Huifeng Li Xianqiang Huang Genban sun Beijing Key Laboratory of Energy Conversion and Storage Materials College of ChemistryBeijing Normal UniversityBeijing 100875China Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology School of Chemistry&Chemical EngineeringLiaocheng UniversityLiaocheng 252059China

Ti3C2 belongs to MXenes family,which is a new two-dimensional material and has been applied in many *** simple method of hydrothermal and high temperature calcination,nano structured Ni/Ti3C2Tx hybrid was *** stable layer structure of Ti3C2 MXene providing high surface area as well as excellent electronic conductivity are beneficial for deposition and decomposition of discharge product ***,possessing special catalytic activity,Ni nanoparticles with size of about 20 nm could accelerate Li2O2 breaking *** advantage of two kinds of materials,Ni/Ti3C2Tx hybrid as cathode of Li-O2 battery can achieve a maximal specific capacity of 20,264 mAh/g in 100 mA/g and 10,699 mAh/g in 500 mA/g at the first *** work confirms that the prepared Ni/Ti3C2Tx hybrid exhibiting better cycling stability points out a new guideline to improve the electrochemical performance of lithium-oxygen batteries.

关键词： MXene Nickel Two-dimensional material Electronic conductivity Lithium-oxygen battery

恩诺沙星对17℃负压环境下猪精子保存效果的影响

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黑龙江畜牧兽医 2019年第21期 122-125页

作者：张兆博郑丽云谷圣臣周琳琳王双孙天娇李琦魏国生李井春黑龙江八一农垦大学动物科技学院

为研究猪精子在17℃负压环境下保存时不同浓度恩诺沙星对精子质量的影响,并探讨恩诺沙星的最适添加浓度,试验在Modena基础稀释液中添加不同浓度恩诺沙星并在17℃负压环境下保存猪精液,利用迈朗全自动精子质量检测仪等检查猪精子活率、... 详细信息

为研究猪精子在17℃负压环境下保存时不同浓度恩诺沙星对精子质量的影响,并探讨恩诺沙星的最适添加浓度,试验在Modena基础稀释液中添加不同浓度恩诺沙星并在17℃负压环境下保存猪精液,利用迈朗全自动精子质量检测仪等检查猪精子活率、路径速度、直线速度和畸形率。结果表明:恩诺沙星浓度为50μg/L时,精子活率、路径速度、直线速度和畸形率都显著高于其他浓度(P<0.05)。说明50μg/L的恩诺沙星有利于17℃负压环境下猪精液的保存。

关键词：恩诺沙星 17℃ 负压猪精子精子质量

Bio-inspired nano rotor investigation based on UVLM

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Biosurface and Biotribology 2020年第1期6卷 20-24页

作者： Zhao Shanyong Liu Zhen sun Yachuan Dang tianjiao Li Shiqi Xi’an Jiaotong University State Key Laboratory for Strength and Vibration of Mechanical Structures Xi’anShaanxi 710049People’s Republic of China

Nano rotor is of great value in military and civilian *** to its nano size,it works at an ultra-low Reynolds number and aerodynamic performance deteriorates *** bio-inspired nano rotor is carried out to improve the rotor propulsive *** vortex lattice method(UVLM)model is established fully considering the influence of induced drag and wake vortex distortion on aerodynamic *** aim is to quickly and accurately simulate the flow field around the bio-inspired nano rotor and to efficiently perform the aerodynamic calculation to optimise the design of the bio-inspired *** rotor parameters and motion parameters such as aspect ratio,taper ratio and camber are studied using *** is found that the aerodynamic performance of the rotor increased with the aspect *** quality factor changes parabolically with the taper ratio and camber,and there is an optimal value for the ratio and camber,*** influences of pitching angle and frequency are investigated as *** show that the bio-inspired motion improves the propulsion performance of nano rotor.

关键词： vortex performance parameters