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基于实际和模型树木的TreeQSM建模估计树木参数性能分析

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中国激光 2023年第22期50卷 157-166页

作者：吴毓涵汪沛李雅新刘重男李汉隆任竞北京林业大学理学院北京100083

树木的量化模型对分析树木拓扑结构和生物量等信息非常重要。树木定量结构模型(TreeQSM)作为主流建模方法,被广泛使用,但在估计树高、胸径和体积的精度上缺少全面分析。实验中用地面激光雷达多扫描角分辨率多站点扫描2棵模型树和5棵真... 详细信息

树木的量化模型对分析树木拓扑结构和生物量等信息非常重要。树木定量结构模型(TreeQSM)作为主流建模方法,被广泛使用,但在估计树高、胸径和体积的精度上缺少全面分析。实验中用地面激光雷达多扫描角分辨率多站点扫描2棵模型树和5棵真实杏树,通过TreeQSM建模单站和多站融合数据估计得到较精确的树高、胸径和体积参数,同时分析不同角度分辨率、不同站点数量对估计树高、胸径和体积的影响。实验结果表明:树高和胸径的平均估计精度均在90%以上;对树木体积而言,结构较为简单的模型树平均估计精度为92.00%,结构较为复杂的真实杏树平均估计精度71.32%。由实验数据可知,扫描角分辨率和融合站数对精度有一定的影响,且不同参数最优估计结果的配置存在差别,同时TreeQSM也会受到点云数据基础、数据完整性和噪声等多因素影响,特别是针对复杂分枝结构和体积进行建模时仍存在一定的偏差,所提模型的改进空间巨大。

关键词：遥感地面激光雷达定量结构模型点云树木重建

“Unveiling the antiviral mechanism of Forsythia suspense: A comprehensive analysis of screening targets and components

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Journal of Chinese Pharmaceutical Sciences 2024年

作者： Na Sun Shuo Ma Linxuan Jin Xin Zhang Miao Zhou Huanhuan Yang Wenqian Li Xinru wu Yanyan Hou yuhan Yuan Yu Zhang Penghua Shu Food and Pharmacy College， Xuchang University

List of Supporting InformationTable S1 The PDB ID， Resolution， and ligand of key antiviral target p

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有机硅烷功能化碳点的制备及应用进展

复合材料学报 2022年第3期39卷 884-895页

作者：曹文兵孙争光武钰涵张玉红詹园湖北大学材料科学与工程学院功能材料绿色制备与应用教育部重点实验室武汉430062 湖北大学化学化工学院武汉430062

碳点(Carbon dots,CDs)因其合成方法简单、原料来源广泛、光致发光性能优异、生物相容性好等优点,在生物成像、荧光探针等方面引起了广泛的研究兴趣。然而,CDs仍存在荧光量子产率低、聚集诱导荧光猝灭等不足,限制了其在光电器件领域中... 详细信息

碳点(Carbon dots,CDs)因其合成方法简单、原料来源广泛、光致发光性能优异、生物相容性好等优点,在生物成像、荧光探针等方面引起了广泛的研究兴趣。然而,CDs仍存在荧光量子产率低、聚集诱导荧光猝灭等不足,限制了其在光电器件领域中的应用。有机硅烷功能化CDs(SiCDs)不仅具有良好的液态荧光,而且能够保持其固态荧光性能,对拓展CDs的应用领域具有重要意义。综述了近年来国内外SiCDs的制备方法、性能调控与应用,总结了SiCDs在发展中存在的问题,并对SiCDs的发展方向进行了展望。

关键词：有机硅烷功能化CDs 制备方法固态荧光生物应用光电器件

Ballistic performances of the hourglass lattice sandwich structures under high-velocity fragments

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Defence Technology（防务技术） 2024年第1期31卷 312-325页

作者： He-xiang wu Jia Qu Lin-zhi wu Key Laboratory of Advanced Ship Materials and Mechanics College of Aerospace and Civil EngineeringHarbin Engineering UniversityHarbin150001China School of Civil Engineering Northeast Forestry UniversityHarbin150040China

In this paper,the numerical simulation method is used to study the ballistic performances of hourglass lattice sandwich structures with the same mass under the vertical incidence of *** is paid to elucidating the influences of rod cross-section dimensions,structure height,structure layer,and rod inclination angle on the deformation mode,ballistic performances,and ability to change the ballistic direction of *** results show that the ballistic performances of hourglass lattice sandwich structures are mainly affected by their structural *** this respect,structural parameters optimization of the hourglass lattice sandwich structures enable one to effectively improve their ballistic limit velocity and,consequently,ballistic performances.

关键词： Hourglass lattice sandwich structures Ballistic performances high-velocity Finite element analysis

Resilience-incorporated seismic risk assessment of precast concrete frames with“dry”connections

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 403-425页

作者： wu Chenhao Tang Yuchuan Cao Xuyang wu Gang Key Laboratory of Concrete and Prestressed Concrete Structures of the Ministry of Education Nanjing 211102China Department of Civil and Environmental Engineering University of CaliforniaLos AngelesCA 90095USA School of Civil Engineering Southeast UniversityNanjing 211102China College of Civil and Transportation Engineering Hohai UniversityNanjing 210024China

A resilience-incorporated risk assessment framework is proposed and demonstrated in this study to manifest the advantageous seismic resilience of precast concrete frame(PCF)structures with“dry”connections in terms of their low damage and rapid *** framework integrates various uncertainties in the seismic hazard,fragility,capacity,demand,loss functions,and post-earthquake *** this study,the PCF structures are distinguished from ordinary reinforced concrete frame(RCF)structures by characterizing multiple limit states for the PCF based on its unique damage ***,probabilistic story-wise pushover analyses are performed to yield story-wise capacities for the predefined limit *** the seismic resilience analysis,a step-wise recovery model is proposed to idealize the functionality recovery process,with separate considerations of the repair and non-repair *** recovery model leverages the economic loss and downtime to delineate the stochastic post-earthquake recovery curves for the resilience loss *** such,contingencies in the probabilistic post-earthquake repairs are incorporated and the empirical judgments on the recovery parameters are largely *** proposed framework is demonstrated through a comparative study between two“dry”connected PCFs and one RCF designed as alternative structural systems for a prototype *** results from the risk quantification indicate that the PCFs show reduced loss hazards and lower expected losses relative to the ***,the PCF equipped with energy dissipation devices at the“dry”connections largely reduces the expected economic loss,downtime,and resilience loss by 29%,56%,and 60%,respectively,compared to the RCF.

关键词： precast concrete frame non-emulative precast system seismic resilience seismic risk functional recovery

New findings on the influence of El Nino events on tropical cyclone formation

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Science China Earth Sciences 2024年第3期67卷 892-893页

作者： Liguang wu Department of Atmospheric and Oceanic Sciences Institute of Atmospheric SciencesFudan UniversityShanghai 200438China

Tropical cyclones typically form over warm tropical and subtropical ocean surfaces, as their formation and intensification rely primarily on the energy provided by the ocean. Pioneering research by Gray (1968) revealed that the formation of tropical cyclones requires the sea surface temperature (SST) to be no less than 26.5℃. Consequently, SST is commonly recognized as a crucial parameter among the environmental factors influencing tropical cyclone formation(Gray, 1979;Emanuel and Nolan, 2004).

关键词： tropical cyclone ocean

一株安庆六白猪源乳酸菌的分离鉴定及生物特性研究

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动物营养学报 2022年第8期34卷 5415-5425页

作者：吴雨晗吴婷涂健李哲盛婷婷李峰姚皓洲安徽农业大学动物科技学院合肥230000

本试验旨在筛选优质猪源乳酸菌,为开发微生态制剂奠定基础。通过加入碳酸钙的MRS固体培养基分离纯化出6株疑似乳酸菌,对上述菌株进行耐受试验、抑菌试验,挑选出1株优秀菌株,再进行产酸试验、黏附性试验,测定其生长曲线和产酸曲线。结果... 详细信息

本试验旨在筛选优质猪源乳酸菌,为开发微生态制剂奠定基础。通过加入碳酸钙的MRS固体培养基分离纯化出6株疑似乳酸菌,对上述菌株进行耐受试验、抑菌试验,挑选出1株优秀菌株,再进行产酸试验、黏附性试验,测定其生长曲线和产酸曲线。结果表明:从六白猪粪样中分离筛选出1株抗逆性好且抑菌活性强的菌株,经过16S rRNA测序、生化鉴定、革兰氏染色鉴定,该菌株为约翰氏乳杆菌(Lactobacillus johnsonii),命名为Tβ。Tβ可以耐受高温与低pH,在pH为2.0时的存活率为12.1%,90℃时的存活率为14.02%。Tβ具有优秀的产酸能力,最低可达到pH 3.4。Tβ对大肠杆菌、沙门氏菌、金黄色葡萄球菌皆具有良好的抑菌效果。体外黏附试验证明Tβ具有较低的自聚合能力,较高的疏水能力,与金黄色葡萄球菌的共凝集性为52.11%,与沙门氏菌的共凝集性为75.64%,与大肠杆菌的共凝集性为73.95%。肠道内定植观察可以明显观察到异硫氰酸荧光素(FITC)标记的Tβ荧光,说明其黏附能力较为优秀。由此可见,Tβ是一株抗逆性、抑菌效果、黏附效果都十分优秀的猪源乳酸菌微生态制剂备用菌株。

关键词：安庆六白猪乳酸菌分离鉴定

Two-dimensional semiconductor heterostructures for photocatalytic CO_(2)conversion

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Science China Chemistry 2024年第8期67卷 2434-2447页

作者： Yang wu Mingyu wu Yongfu Sun Yi Xie Hefei National Research Center for Physical Sciences at Microscale University of Science and Technology of ChinaHefei 230026China

The CO_(2)reduction into carbon-contained fuel via solar energy offers the powerful tools to realize the zero-emission carbon *** to the intriguing features of the two-dimensional(2D)heterostructures,it is susceptible to modulate the electronic structure as well as the surface geometry for optimizing the photocatalytic CO_(2)*** this perspective,we surveyed the fundamental insights of 2D semiconductor heterostructures,involving the fabrication strategies and classification of the 2D semiconductor ***,we have detailly discussed the overview of 2D semiconductor heterostructure for optimizing CO_(2)photocatalytic influenced factors,including the solar energy utilization,photogenerated carriers separation,and redox reaction ***,we showed the significant advantages of 2D heterostructures in elevating CO_(2)photoreduction performance,focusing on activity,selectivity and *** analyzing the limitations and developments,we ended by putting forward insights into the further researches about the CO_(2)photocatalysts and reactor design,even industrial applications.

关键词： two-dimensional semiconductor heterostructures photocatalysis CO_(2)conversion

浸液pH值对铂催化剂反应性能和表面性质的影响

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燃料化学学报 1990年第2期18卷 15-21页

作者：孙予罕吴东陈诵英彭少逸中国科学院山西煤炭化学研究所中国科学院山西煤炭化学研究所太原

本文研究浸液pH值对铂催化剂性能的影响。用烷烃连续流动反应技术以及TPR、XPS、DRS和IR等手段表征催化剂表面性质因强酸处理产生的变化。结果表明:浸液pH值显著影响催化剂的反应性能。随浸液酸度增加,正己烷异构化和芳构化选择性呈线... 详细信息

本文研究浸液pH值对铂催化剂性能的影响。用烷烃连续流动反应技术以及TPR、XPS、DRS和IR等手段表征催化剂表面性质因强酸处理产生的变化。结果表明:浸液pH值显著影响催化剂的反应性能。随浸液酸度增加,正己烷异构化和芳构化选择性呈线性增大,但却不影响铂的脱氢性能;并且酸度增加导致催化剂酸性（异丙苯裂解活性）下降和高温（>300℃）吸氢中心增加。测试数据也表明,酸处理导致载体表面性质发生了较大变化,氧化态铂物种与载体相互作用增强,部分铂变得较难还原。上述现象归因于在酸性条件下,酸解生成的Al3+离子的再吸附,以及催化剂表面铂簇团短程有序结构的形成和非零价铂的存在。

关键词：溶液pH值铂催化剂烃转化反应