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Impact of Sky Conditions on Net Ecosystem Productivity over a “Floating Blanket” Wetland in Southwest China

Advances in Atmospheric Sciences 2024年第2期41卷 355-368页

作者： yamei shao Huizhi LIU Qun DU Yang LIU Jihua SUN Yaohui LI Jinlian LI State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100029China Yunnan Meteorological Observatory Kunming 530100China College of Aviation Meteorology Civil Aviation Flight University of ChinaGuanghan 618307China Meteorological Bureau of Tengchong County Baoshan 679100China

Based on eddy covariance(EC) measurements during 2016–20, the effects of sky conditions on the net ecosystem productivity(NEP) over a subtropical “floating blanket ” wetland were investigated. Sky conditions were divided into overcast, cloudy, and sunny conditions. On the half-hourly timescale, the daytime NEP responded more rapidly to the changes in the total photosynthetic active radiation(PARt) under overcast and cloudy skies than that under sunny skies. The increase in the apparent quantum yield under overcast and cloudy conditions was the greatest in spring and the least in summer. Additionally, lower atmospheric vapor pressure deficit(VPD) and moderate air temperature were more conducive to enhancing the apparent quantum yield under cloudy skies. On the daily timescale, NEP and the gross primary production(GPP) were higher under cloudy or sunny conditions than those under overcast conditions across seasons. The daily NEP and GPP during the wet season peaked under cloudy skies. The daily ecosystem light use efficiency(LUE) and water use efficiency(WUE) during the wet season also changed with sky conditions and reached their maximum under overcast and cloudy skies, respectively. The diffuse photosynthetic active radiation(PAR_d) and air temperature were primarily responsible for the variation of daily NEP from half-hourly to monthly timescales, and the direct photosynthetic active radiation(PAR_b) had a secondary effect on NEP. Under sunny conditions, PAR_b and air temperature were the dominant factors controlling daily NEP. While daily NEP was mainly controlled by PAR_d under cloudy and overcast conditions.

关键词： diffuse radiation eddy covariance NEP controlling factors wetland path analysis

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青藏高原东南缘不同类型生态系统碳、水交换特征

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大气科学 2024年第1期48卷 188-199页

作者：刘辉志杜群许鲁君刘阳蒙小妮邵雅梅郑颖祺中国科学院大气物理研究所大气边界层物理和大气化学国家重点实验室北京100029 云南大学昆明650500 中国科学院大学北京100049 南宁师范大学北部湾环境演变与资源利用教育部重点实验室南宁530001 生态环境部南京环境科学研究所南京210042

青藏高原东南缘横断山脉地区是南亚和东亚季风的交汇处,也是大气变化的敏感区和热源区。开展该地区地气相互作用对区域水热过程影响机制及其参数化研究,对于研究青藏高原大气水汽传输的关键过程问题有重大意义。本文介绍了基于涡动观测... 详细信息

青藏高原东南缘横断山脉地区是南亚和东亚季风的交汇处,也是大气变化的敏感区和热源区。开展该地区地气相互作用对区域水热过程影响机制及其参数化研究,对于研究青藏高原大气水汽传输的关键过程问题有重大意义。本文介绍了基于涡动观测法开展的青藏高原东南缘地区的地气相互作用观测试验,并总结了洱海湖面、丽江高山草甸及腾冲北海湿地的地气交换特征,以及利用数值模式开展复杂山地局地环流特征的研究工作。目前已初步明确和揭示青藏高原东南缘横断山脉不同类型下垫面的地气交换特征及其影响因素,主要结论如下:青藏高原东南缘高山草甸的碳、水交换过程受降水分布影响显著,“浮毯型”湿地(水面常年覆盖有“浮毯”状苔草草排)的碳、水交换除了受气象因素影响外,也受到下垫面植被和水体比例变化的影响。不同类型生态系统的碳、水交换过程在不同时间尺度的影响因子存在差别。风速始终是湖泊潜热和CO_(2)交换的关键影响因子,而降水在较长时间尺度对湖泊CO_(2)通量也有显著影响。此外,青藏高原东南缘的复杂地形对于生态系统的碳、水交换过程也有显著影响。复杂地形产生的不同类型的局地环流对于生态系统的碳、水交换过程有不同的影响。

关键词：地气相互作用潜热通量净碳交换涡动相关

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Optical pulse repetition rate division using an optoelectronic oscillator

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Chinese Optics Letters 2024年第4期22卷 125-129页

作者：李平邵琨麟张亚梅潘时龙 National Key Laboratory of Microwave Photonics Nanjing University of Aeronautics and AstronauticsNanjing 210016China

An approach for frequency division of an optical pulse train(OPT) based on an optoelectronic oscillator(OEO) is proposed and experimentally demonstrated. When the OPT is injected into the OEO, a microwave signal with a frequency equaling fractional multiples of the repetition rate of the OPT is generated. This signal is then fed back to the OEO, maintaining its oscillation, while simultaneously serving as the control signal of a Mach–Zehnder modulator(MZM) in the OEO. The MZM acts as an optical switch, permitting specific pulses to pass through while blocking others. As a result, the repetition rate of the OPT is manipulated. A proof-of-concept experiment is carried out. Frequency division factors of 2 and 3 are successfully achieved. The phase noises of the OPT before and after the frequency division are investigated. Compared to previously reported systems, no external microwave source and sophisticated synchronization structure are needed.

关键词： frequency division optoelectronic oscillator mode-locked laser microwave photonics

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Green Hydrothermal Synthesis and Applications of Sorbus pohuashanensis/Aronia melanocarpa Extracts Functionalized-Au/Ag/AuAg Nanoparticles

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Journal of Renewable Materials 2023年第4期11卷 1807-1821页

作者： Jin Huang Jixiang Sun Kai shao yamei Lin Zhiguo Liu Yujie Fu Liqiang Mu College of Chemistry Chemical Engineering and Resource UtilizationKey Laboratory of Forest Plant Ecology Ministry of EducationNortheast Forestry UniversityHarbin150040China School of Forestry Northeast Forestry UniversityHarbin150040China Heilongjiang Provincial Key Laboratory of Ecological Utilization of Forestry-Based Active Substances Harbin150040China National Engineering Laboratory of Bio-Resource Eco-Utilization Harbin150040China

Nanoparticles(NPs)have already been widely used in catalysis,antibacterial and coating fields.Compared with the traditional toxic and harmful reducing reagents,green synthesis of NPs by using plant extracts is not only environmental-friendly and cost-effective but also conducive to the multi-level and efficient utilization of wild plant resources.In this study,the aqueous extracts from Sorbus pohuashanensis(SP)and Aronia melanocarpa(AM)fruits were used as the reducing and protective reagents for synthesizing Au/AgNPs,with the characteristics of originality operation and high repeatability.The SP/AM fruit extracts functionalized Au/AgNPs were characterized by UV-vis spectroscopy(UV-vis),transmission electron microscopy(TEM),energy dispersive spectroscopy(EDS),scanning electron microscope(SEM),X-ray diffraction(XRD)and Fourier transform infrared spectroscopy(FTIR).UV-vis spectrums showed the NPs peaks verified by the presence between 400–550 nm;TEM and SEM demonstrated NPs displayed approximately spherical structures;EDS confirmed the existence of Au/Ag elements;XRD measurements confirmed that the obtained NPs showed highly crystalline structures;FTIR demonstrated the fruits extracts were adsorbed on the surface of NPs.Primary experiments indicated that SP/AM fruit extracts functionalized-NPs could be used as the reagents for removing the organic dyes efficiently;Zone of inhibition tests(ZOI)explained that NPs have slow-release antibacterial activity.

关键词： Green synthesis nanoparticles Sorbus pohuashanensis Aronia melanocarpa plant extracts dye removal

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Cranial irradiation impairs intrinsic excitability and synaptic plasticity of hippocampal CA1 pyramidal neurons with implications for cognitive function

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Neural Regeneration Research 2022年第10期17卷 2253-2259页

作者： Min-Yi Wu Wen-Jun Zou Pei Yu Yuhua Yang shao-Jian Li Qiang Liu Jiatian Xie Si-Qi Chen Wei-Jye Lin yamei Tang Department of Neurology Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina State Key Laboratory of Organ Failure Research Key Laboratory of Mental Health of the Ministry of EducationGuangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired IntelligenceKey Laboratory of Psychiatric Disorders of Guangdong ProvinceCollaborative Innovation Center for Brain ScienceDepartment of NeurobiologySouthern Medical UniversityGuangzhouGuangdong ProvinceChina Department of Anesthesiology Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation Guangdong-Hong Kong Joint Laboratory for RNA MedicineSun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Medical Research Center Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Guangdong Province Key Laboratory of Brain Function and Disease Zhongshan School of MedicineSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina

Radiation therapy is a standard treatment for head and neck tumors.However,patients often exhibit cognitive impairments following radiation therapy.Previous studies have revealed that hippocampal dysfunction,specifically abnormal hippocampal neurogenesis or neuroinflammation,plays a key role in radiation-induced cognitive impairment.However,the long-term effects of radiation with respect to the electrophysiological adaptation of hippocampal neurons remain poorly characterized.We found that mice exhibited cognitive impairment 3 months after undergoing 10 minutes of cranial irradiation at a dose rate of 3 Gy/min.Furthermore,we observed a remarkable reduction in spike firing and excitatory synaptic input,as well as greatly enhanced inhibitory inputs,in hippocampal CA1 pyramidal neurons.Corresponding to the electrophysiological adaptation,we found reduced expression of synaptic plasticity marker VGLUT1 and increased expression of VGAT.Furthermore,in irradiated mice,long-term potentiation in the hippocampus was weakened and GluR1 expression was inhibited.These findings suggest that radiation can impair intrinsic excitability and synaptic plasticity in hippocampal CA1 pyramidal neurons.

关键词： GABA-mediated hyperfunction GluR intrinsic excitability long-term potentiation radiation-induced cognitive impairment spontaneous excitatory postsynaptic currents spontaneous inhibitory postsynaptic currents synaptic plasticity type I vesicular glutamate transporter vesicular GABA transporter whole-cell patch clamp recording

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13种浙江省野生铁线莲引种驯化与观赏性评价

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中国园林 2022年第11期38卷 116-121页

作者：邵伟丽刘志高申亚梅季梦成浙江农林大学风景园林与建筑学院杭州311300 浙江农林大学杭州311300 浙江农林大学浙江省园林植物种质创新与利用重点实验室杭州311300

为保护和合理开发本土铁线莲属植物资源,对原产浙江省的13种铁线莲进行引种驯化栽培,并结合对叶、花、果表型特征连续4年的物候观测结果,采用层次分析(AHP)和聚类分析法开展观赏性评价。结果显示:13种铁线莲在杭州市临安区引种栽培后均... 详细信息

为保护和合理开发本土铁线莲属植物资源,对原产浙江省的13种铁线莲进行引种驯化栽培,并结合对叶、花、果表型特征连续4年的物候观测结果,采用层次分析(AHP)和聚类分析法开展观赏性评价。结果显示:13种铁线莲在杭州市临安区引种栽培后均能完成生活史;可分为常绿、半常绿和落叶3个生态型;花期覆盖冬季(12—翌年2月)、春季(4—6月)和夏季(7—8月),花萼以白色为主,也有蓝紫、淡紫、紫红等色彩;除重瓣铁线莲外均具有较强的结实能力,是优良的育种亲本资源。根据AHP评价和聚类分析结果,毛叶铁线莲综合评分和观花评分均为最高(I级),观赏性优异;3个常绿种类舟柄铁线莲、单叶铁线莲和柱果铁线莲的观叶评分最高(I级);舟柄铁线莲、单叶铁线莲、柱果铁线莲等7个种类在果序观赏性评分中为I级;13种铁线莲可按照观叶、观花和观果特点进行造景应用,对夏季强光敏感的单叶铁线莲等种类可选择适度荫蔽的小环境栽培。本研究将为中国本土野生铁线莲资源开发和园林应用提供重要参考。

关键词：园林植物铁线莲属浙江省种质资源引种驯化观赏性评价

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CCGD-ESCC： A Comprehensive Database for Genetic Variants Associated with Esophageal Squamous Cell Carcinoma in Chinese Population

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Genomics, Proteomics & Bioinformatics 2018年第4期16卷 262-268页

作者： Linna Peng Sijin Cheng Yuan Lin Qionghua Cui Yingying Luo Jiahui Chu Mingming shao Wenyi Fan yamei Chen Ai Lin Yiyi Xi Yanxia Sun Lei Zhang Chao Zhang Wen Tan Ge Gao Chen Wu Dongxin Lin Department of Etiology and Carcinogenesis National Cancer Center/Cancer Hospital Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China State Key Laboratory of Protein and Plant Gene Research School of Life Sciences Center for Bioinformatics Peking UniversityBeijing 100871China Beijing Advanced Innovation Center for Genomics (ICG) Peking UniversityBeijing 100871China National Engineering Research Center for Beijing Biochip Technology Beijing 102206China School of Life Sciences Peking UniversityBeijing 100871China

Esophageal squamous-cell carcinoma （ESCC） is one of the most lethal malignancies in the world and occurs at particularly higher frequency in China. While several genome-wide association studies （GWAS） of germline variants and whole-genome or whole-exome sequencing studies of somatic mutations in ESCC have been published, there is no comprehensive database publically available for this cancer. Here, we developed the Chinese Cancer Genomic Database-Esophageal Squamous Cell Carcinoma （CCGD-ESCC） database, which contains the associations of 69,593 single nucleotide polymorphisms （SNPs） with ESCC risk in 2022 cases and 2039 controls, survival time of 1006 ESCC patients （survival GWAS） and gene expression （expression quantitative trait loci,eQTL） in 94 ESCC patients. Moreover, this database also provides the associations between8833 somatic mutations and survival time in 675 ESCC patients. Our user-friendly database is a resource useful for biologists and oncologists not only in identifying the associations of genetic variants or somatic mutations with the development and progression of ESCC but also in studying the underlying mechanisms for tumorigenesis of the cancer. CCGD-ESCC is freely accessible at http：//***/ccgd/ESCCdb.

关键词： Esophageal cancer Germline variants Somatic mutations Association databaseChinese population

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转向节耐久性试验系统设计与分析

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机械强度 2022年第6期44卷 1435-1442页

作者：罗雅梅杨练根王斌邵光保何涛朱永平湖北工业大学机械工程学院武汉430068 湖北三环锻造有限公司襄阳441700

传统的转向节耐久性试验台只能进行单轴加载试验,不能完全模拟实际路况下转向节的受力状况。针对此问题,提出了一种模拟实时路况、四轴加载的转向节耐久性试验系统。首先构建了试验系统机械部分的三维模型,对立柱的强度进行了设计并对... 详细信息

传统的转向节耐久性试验台只能进行单轴加载试验,不能完全模拟实际路况下转向节的受力状况。针对此问题,提出了一种模拟实时路况、四轴加载的转向节耐久性试验系统。首先构建了试验系统机械部分的三维模型,对立柱的强度进行了设计并对关键硬件进行了选型;其次利用Ansys Workbench进行模态分析,得到了试验系统的前6阶振型及固有频率,再通过理论计算出轮胎传递给转向节的外界激励频率分别为8.47 Hz和104.4 Hz,与机械子系统的固有频率不一致,验证了试验系统在标准加载频率范围内不会产生共振现象;最后,搭建了试验系统并进行了测试,将采集的数据利用Matlab进行FFT频谱分析,得出加载力的误差最大为0.95 kN,远小于最大允许误差±2.5 kN,频率的平均误差为1.35%。结果表明,转向节耐久性试验系统的性能满足要求,能模拟实际工况,为转向节耐久性试验提供了可靠的理论依据。

关键词：转向节耐久性试验系统模态分析 Ansys

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基于声学特征信号识别的高速机械开关故障检测方法研究

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高压电器 2023年第8期59卷 186-195页

作者：田阳郭媛媛李亚美邵明鑫徐党国中国电力科学研究院有限公司北京100192 国网冀北电力有限公司电力科学研究院北京100045

世界首次研制的500kV高压直流断路器已投入运行,高速机械开关是直流断路器重要部件,对高速机械开关运行过程中机械状态准确评估,是确保直流断路器全寿命周期内长时无故障运行的关键。文中结合张北柔直工程运维需求,分析了高速机械开关... 详细信息

世界首次研制的500kV高压直流断路器已投入运行,高速机械开关是直流断路器重要部件,对高速机械开关运行过程中机械状态准确评估,是确保直流断路器全寿命周期内长时无故障运行的关键。文中结合张北柔直工程运维需求,分析了高速机械开关单元结构特点及工作原理,并结合运行经验,确定主驱动轴松动和储能电容不足两种典型故障类型。提出了声学信号采集关键技术指标,开发设计了声学信号采集和分析系统,开展高速机械开关声学信号采集和快速分闸特性关联测试试验,基本确定声学信号适用性。在声学传感器的15个预置位置分别采集高速机械开关单元正常状态分闸、主驱动轴松动和储能电容容量不足典型故障下分闸时的声学样本数据集,利用构建的EMD-GRU高速机械开关单元故障识别算法模型,对声学信号样本数据集进行训练和验证,获得传感器不同布置位置的准确率。对两种典型故障的声学信号进行了经验模态分解,分析出了两种典型故障声学特征信号窄时域时间点和峰值组数的关联差异。结果表明,文中提出的基于声学特征信号识别的高速机械开关故障检测方法可相对准确区分正常分闸、故障(主驱动轴松动、储能电容量不足)分闸状态下声学信号,识别准确率可达到93.3%,为后续工程化应用打下坚实基础。

关键词：直流断路器高速机械开关声学信号样本数据故障识别

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铁线莲栽培品种观赏性综合评价体系的建立与应用

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浙江农林大学学报 2022年第6期39卷 1229-1237页

作者：邵伟丽廖娣华刘志高申亚梅董彬杨丽媛浙江农林大学风景园林与建筑学院浙江杭州311300 浙江农林大学浙江省园林植物种质创新与利用重点实验室浙江杭州311300

【目的】建立铁线莲属Clematis栽培品种观赏性综合评价体系,为合理引进和应用铁线莲栽培品种资源提供理论依据。【方法】对20个铁线莲品种植株、叶、花、果性状的生长物候期进行调查,采用层次分析和灰色关联度分析法,评价其观赏性。【... 详细信息

【目的】建立铁线莲属Clematis栽培品种观赏性综合评价体系,为合理引进和应用铁线莲栽培品种资源提供理论依据。【方法】对20个铁线莲品种植株、叶、花、果性状的生长物候期进行调查,采用层次分析和灰色关联度分析法,评价其观赏性。【结果】(1)20个铁线莲品种可分为常绿和落叶2种生态型。(2)植株在杭州地区的萌芽期、抽枝展叶期多集中在2月上中旬至3月中下旬,花期多处于4—6月(‘蓝焰’‘Bagatelle’和‘蓝光’‘Blue Light’等7个品种在7—12月可以2次开花)。(3)萼片多为紫红色系、蓝紫色系或具2种颜色以上的复色系。【结论】经观赏性评价和聚类分析,‘蓝焰’和‘茱莉亚夫人’‘Madame Julia Correvon’的综合评价得分最高(Ⅰ级),Ⅱ级含‘羞嗒嗒’‘Innocent Blush’等4个品种,Ⅲ级包括‘乌托邦’‘Utopia’在内的3个品种,Ⅳ级包括‘朱卡’‘Julka’在内的9个品种,Ⅴ级含‘蓝光’和‘丹尼尔德隆达’‘Danniel Deronda’。Ⅰ和Ⅱ级的6个品种可优先在杭州地区推广应用。表12参17。

关键词：铁线莲属栽培品种生长适应性物候观测观赏性评价

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