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Decomposition dynamics and ecological stoichiometry of Quercus acutissima and Pinus densiflora li.ter in the Grain to Green Program Area of northern China

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Journal of Forestry Research 2020年第5期31卷 1613-1623页

作者： Jianni Sun Peng Gao Haidong Xu cheng li.Xiang Niu Forestry College Mountain Tai Forest Ecosystem Research Station of State Forestry AdministrationShandong Provincial Key Laboratory of Soil Erosion and Ecological RestorationShandong Agricultural UniversityTai’an 271018ShandongPeople’s Republic of China Research Institute of Forest Ecology Environment and ProtectionChinese Academy of ForestryBeijing Collaborative Innovation Center for Eco-Environmental Improvement With Forestry and Fruit TreesBeijing 100091People’s Republic of China

li.ter decomposition and ecological stoichiometry of nutrient release is an important part of material cycli.g and energy flow in forest *** a study of the ecological stoichiometry and nutrient release during li.ter decomposition in a pine–oak forest ecosystem of the Grain to Green Program(GTGP)area of northern China,a typical pine and oak species(PDS:Pinus densiflora Sieb.,QAC:Quercus acutissima Carr.)were selected in the Taiyi Mountain study *** ecological stoichiometry characteristics of carbon(C),nitrogen(N)and phosphorus(P)and li.ter decomposition dynamics were studied by field sampli.g and quantitative *** results showed the following.(1)The decomposition dynamics of both li.ters was *** most important cli.atic factor affecting the li.ter decomposition rate from May to October was precipitation and temperature from November to April of the following year.(2)Throughout the 300-day study,in both li.ters,C of the two li.ters was released,N first accumulated and was then released,and P exhibited a release-accumulate-release pattern.(3)C:P was significantly higher than C:N and N:P(pli.ter was higher than that of QAC(pli.ter was higher than that of PSD li.ter(pli.ters was very high in the study area,indicating that the nutrient release abili.y during li.ter decomposition in the two typical pine–oak forest ecosystems was relatively weak;therefore,more attention should be paid to nitrogen-fixing species and mixed forests in the GTGP area of northern China.

关键词： Decomposition dynamics Ecological stoichiometry li.ter Pinus densiflora Quercus acutissima Grain to Green Program(GTGP)

Submesoscale motions and their seasonali.y in the northern Bay of Bengal

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Acta Oceanologica Sinica 2022年第4期41卷 1-13页

作者： Lanman li.Xuhua cheng Zhiyou Jing Haijin Cao Tao Feng College of Oceanography Hohai UniversityNanjing 210098China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China

The unbalanced submesoscale motions and their seasonali.y in the northern Bay of Bengal(BoB)are investigated using outputs of the high resolution regional oceanic modeli.g *** motions in the forms of filaments and eddies are present in the upper mixed layer during the whole annual *** motions show an obvious seasonali.y,in which they are active during the winter and spring but weak during the summer and *** seasonali.y is associated with the mixed layer instabili.y that depends on the mixed layer depth(MLD).During the winter,the MLD provides a much greater reservoir of the available potential energy,which promotes mixed layer instabili.y to develop active submesoscale *** variations of MLD are li.ely modulated by the larger scale motions and the influxes of *** investigations imply that the MLD and the stratified barrier layer are combined to determine the vertical structure of the submesoscale *** shallow MLD and strong stratification below during the summer and fall seem to prevent the downward extension of submesoscale *** in spring when the weak stratification exists,the penetration depth exceeds the base of the barrier layer.

关键词： submesoscale motions seasonali.y northern BoB mixed layer instabili.y stratification

基于ZYNQ的水下双目实时图像采集与处理系统设计

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光学仪器 2024年第3期46卷 73-79页

作者：张崇丙李晓伟魏柠阳成月李锦中国船舶科学研究中心江苏无锡214082

针对水下机器人近距离作业过程的水下目标探测需求,设计了一种基于ZYNQ的双目实时图像采集与处理系统,研制了水下双目相机工程样机。该系统由FPGA采集OV5640图像传感器的视频数据,经IP核转换为VDMA支持的接口类型,通过AXI4总线将数据传... 详细信息

针对水下机器人近距离作业过程的水下目标探测需求,设计了一种基于ZYNQ的双目实时图像采集与处理系统,研制了水下双目相机工程样机。该系统由FPGA采集OV5640图像传感器的视频数据,经IP核转换为VDMA支持的接口类型,通过AXI4总线将数据传输到PS端的DDR中缓存,然后通过PS端的以太网将数据发送至上位机软件,数据经上位机软件解析后即可实现双目图像的实时显示与处理。实验结果表明:系统实现了在25frame/s帧率下1600 pixel×600 pixel图像的实时采集和存储,双目图像标定后的重投影误差平均值为0.0542 pixel,通过立体校正实现了双目图像行对齐。这为进一步测试和实现水下目标测量定位及三维重建提供了可靠平台。

关键词：双目相机 ZYNQ 图像处理相机标定

Organoimido functionali.ed trinuclear gold(Ⅰ)clusters with fluorescent chromophore

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Rare Metals 2021年第6期40卷 1437-1442页

作者： Chun-li. Lv Chen-Huai Yang li.Ya li. Zhi-cheng Zhang Key Laboratory of Ethnomedicine(Minzu University of China) Ministry of EducationBeijing 100081China School of Pharmacy and Center on Translational Neuroscience Minzu University of ChinaBeijing 100081China Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of ScienceTianjin University&Collaborative Innovation Center of Chemical Science and EngineeringTianjin 300072China College of li.e and Environmental Sciences Minzu University of ChinaBeijing 100081China

The post-functionali.ation of gold nanoclusters with organic molecules into organic-inorganic hybrid functional materials is an efficient approach to develop multifunctional *** introducing 1-pyrenamine and 3-aminofluoranthene into[O(AuPPh_(3))_(3)][BF_(4)]with a covalent bond,two novel organoimido functionali.ed trinuclear gold nanoclusters[C_(16)H_(9)N(AuPPh_(3))_(3)][BF_(4)](Au_(3)-P)and[C_(6)H_(4)-C_(10)H_(5)N(AuPPh_(3))_(3)][BF_(4)](Au_(3)-F)have been successfully *** structures have been determined by electrospray ionization mass spectroscopy(ESI-MS)and single-crystal X-ray diffraction(SC-XRD),and the photoluminescence properties have been investigated from both experimental and theoretical *** is found that the lowest-energy electronic transitions in the ultraviolet-visible(UV-Vis)absorption spectra of Au_(3)-P(403 nm)and Au_(3)-F(425 nm)exhibit a sli.ht bathochromic shift compared to the corresponding transitions in the spectra of 1-pyrenamine and 3-aminofluoranthene,*** addition,the dichloromethane solutions of Au_(3)-P and Au_(3)-F complexes clearly display blue and yellowish-green fluorescence,*** results will help to design and prepare organic-inorganic nanocluster hybrid luminescent materials for potential appli.ations in(bio)sensors,bioimaging and optoelectronic devices.

关键词： Nanoclusters Gold Organoimido Photoluminescence

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多发性硬化和视神经脊髓炎的脑灰质结构分析

解剖学报 2024年第1期55卷 17-24页

作者：刘晓丽许琳吴爱雪闻彩云李如画吴安婷陈黛茜陈成春温州医科大学基础医学院解剖学教研室浙江温州325000 荆门市第一人民医院检验科湖北荆门448001 温州医科大学附属第一医院放射科浙江温州325000 温州医科大学附属第一医院中医科浙江温州325000

目的利用基于体素的形态学测量(VBM)和基于皮层的脑形态学测量(SBM)方法对多发性硬化(MS)和视神经脊髓炎(NMO)患者脑灰质体积及皮层厚度进行比较分析,探讨这两种疾病的脑灰质结构变化的差异。方法对21例MS患者,16例NMO患者以及19例健康... 详细信息

目的利用基于体素的形态学测量(VBM)和基于皮层的脑形态学测量(SBM)方法对多发性硬化(MS)和视神经脊髓炎(NMO)患者脑灰质体积及皮层厚度进行比较分析,探讨这两种疾病的脑灰质结构变化的差异。方法对21例MS患者,16例NMO患者以及19例健康对照者行磁共振常规序列扫描,基于Matlab2014a平台的统计参数工具SPM12以及SPM12下的小工具CAT12,对VBM和SBM方法处理的数据进行分析。结果MS组与正常对照(NC)组相比,经高斯随机场(GRF)校正后,MS组在左侧枕上回、左侧楔叶、左侧距状皮质、左侧楔前叶、左侧中央后回、左侧中央旁小叶、右侧楔叶、左侧额中回、左侧额上回和左侧额内侧回灰质体积显著性减少(P<0.05);经族系错误(FWE)法校正后,MS组在左侧中央旁小叶、左侧额上回和左侧楔前叶皮层厚度显著性减少(P<0.05)。NMO组与NC组相比,经GRF校正后,NMO组在左侧中央后回、左侧中央前回、左侧顶下小叶、右侧中央前回和右侧额中回灰质体积显著性增加(P<0.05);NMO组在左侧枕中回、左侧枕上回、左侧颞下回、右侧枕中回、左侧额上回眶部、右侧中扣带回、左侧前扣带回、右侧角回和左侧楔前叶灰质体积显著性减少(P<0.05);经FWE校正后,NMO组与NC组相比皮层厚度没有显著性差异的脑区。MS组与NMO组相比,经GRF校正后,MS组在右侧梭状回和右侧额中回灰质体积显著性增加(P<0.05);MS组在左侧丘脑、左侧苍白球、左侧中央前回、左侧额中回、左侧颞中回、右侧苍白球、左侧顶下小叶和右侧顶上小叶灰质体积显著性减少(P<0.05);经FWE校正后,MS组在左侧顶下小叶、左侧顶上小叶、左侧缘上回、左侧中央旁小叶、左侧额上回和左侧楔前叶皮层厚度显著性减少(P<0.05)。结论MS患者脑灰质结构萎缩主要累及左侧顶叶区域,NMO患者对于脑灰质结构的改变不敏感。MS患者与NMO患者差异显著性的脑区主要位于脑深部灰质相关核团。

关键词：多发性硬化视神经脊髓炎脑结构基于体素的形态学分析基于皮层的脑形态学分析人

胎盘NLRP3和TLR4及Fasl对未足月胎膜早破产妇宫内感染的诊断价值

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中华医院感染学杂志 2024年第4期34卷 571-575页

作者：雷世正喻萍程蓉胡秦菲李永文四川省人民医院东院妇产科四川成都610000

目的探讨胎盘NOD样受体热蛋白结构域相关蛋白3(NLRP3)、Toll样受体4(TLR4)、脂肪酸合成酶配体(Fasl)对未足月胎膜早破产妇宫内感染的诊断价值.方法回顾性分析2021年3月—2023年3月四川省人民医院收治的未足月胎膜早破产妇172例的临床资... 详细信息

目的探讨胎盘NOD样受体热蛋白结构域相关蛋白3(NLRP3)、Toll样受体4(TLR4)、脂肪酸合成酶配体(Fasl)对未足月胎膜早破产妇宫内感染的诊断价值.方法回顾性分析2021年3月—2023年3月四川省人民医院收治的未足月胎膜早破产妇172例的临床资料,根据宫内感染分为感染组53例和非感染组119例;分析两组临床资料,归纳未足月胎膜早破产妇宫内感染的危险因素;采用免疫组化法和实时荧光定量聚合酶链反应(RT-qPCR)分别检测胎盘NLRP3阳性率及Toll样受体4(TLR4)、脂肪酸合成酶l(Fasl)水平;比较两组胎盘NLRP3阳性率、TLR4、Fasl表达水平;采用受试者工作特征(ROC)曲线分析NLRP3、TLR4、Fasl单独及联合检测对未足月胎膜早破产妇宫内感染的诊断价值.结果阴道检查次数、破膜孕周、中性粒细胞与淋巴细胞比值(NLR)、红细胞分布宽度(RDW)及降钙素原(PCT)是未足月胎膜早破产妇宫内感染的危险因素(P<0.05);感染组胎盘NLRP3阳性表达率及TLR4、Fasl水平均高于非感染组(P<0.05);绘制ROC曲线获得NLRP3、TLR4、Fasl单独及联合检测诊断未足月胎膜早破产妇宫内感染的曲线下面积(AUC)分别为0.787、0.744、0.721和0.917,联合检测的AUC高于各项单独检测(P<0.05),且联合检测的敏感度和特异度为84.90%,84.00%.结论未足月胎膜早破产妇宫内感染患者胎盘NLRP3、TLR4、Fasl呈高表达;联合检测NLRP3、TLR4、Fasl有助于诊断未足月胎膜早破产妇宫内感染;阴道检查次数、破膜孕周、NLR、RDW及PCT是未足月胎膜早破产妇宫内感染的危险因素.

关键词：胎膜早破宫内感染危险因素 NOD样受体热蛋白结构域相关蛋白3 Toll样受体4 脂肪酸合成酶配体诊断价值受试者工作特征曲线

High performance of hot-carrier generation,transport and injection in TiN/TiO_(2)junction

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Frontiers of physics 2022年第5期17卷 35-45页

作者： Tingting li. Qianjun Wang cheng Zhang Xiaofeng li.Jun Hu School of Optoelectronic Science and Engineering&Collaborative Innovation Center of Suzhou Nano Science and Technology Soochow UniversitySuzhou 215006China Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province&Key Lab of Modern Optical Technologies of Education Ministry of China Soochow UniversitySuzhou 215006China School of Physical Science and Technology Soochow UniversitySuzhou 215006China School of Physical Science and Technology Ningbo UniversityNingbo 315211China

Improving the performance of generation,transport and injection of hot carriers within metal/semiconductor junctions is critical for promoting the hot-carrier ***,the conversion efficiency of hot carriers in the commonly used noble metals(e.g.,Au)is extremely ***,through a systematic study by first-principles calculation and Monte Carlo simulation,we show that TiN might be a promising plasmonic material for high-efficiency hot-carrier *** with Au,TiN shows obvious advantages in the generation(high density of low-energy hot electrons)and transport(long li.etime and mean free path)of hot *** further performed a device-oriented study,which reveals that high hotcarrier injection efficiency can be achieved in core/shell cyli.drical TiN/TiO_(2)*** findings provide a deep insight into the intrinsic processes of hot-carrier generation,transport and injection,which is helpful for the development of hot-carrier devices and appli.ations.

关键词： metal/semiconductor junction plasmonic material hotcarrier generation li.etime and mean free path injection efficiency

Dynamic mass variation and multiphase interaction among steel, slag, li.ing refractory and nonmetalli. inclusions: Laboratory experiments and mathematical prediction

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International Journal of Minerals,Metallurgy and Materials 2021年第8期28卷 1298-1308页

作者： Ju-jin Wang li.feng Zhang Gong cheng Qiang Ren Ying Ren School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China

The mass transfer among the multiphase interactions among the steel, slag, li.ing refractory, and nonmetalli. inclusions during the refining process of a bearing steel was studied using laboratory experiments and numerical kinetic prediction. Experiments on the system with and without the slag phase were carried out to evaluate the influence of the refractory and the slag on the mass transfer. A mathematical model coupled the ion and molecule coexistence theory, coupled-reaction model, and the surface renewal theory was establi.hed to predict the dynamic mass transfer and composition transformation of the steel, the slag, and nonmetalli. inclusions in the steel. During the refining process,Al_(2)O_(3) inclusions transformed into Mg O inclusions owing to the mass transfer of [Mg] at the steel/refractory interface and(Mg O) at the slag/refractory interface. Most of the aluminum involved in the transport entered the slag and a small part of the aluminum transferred to li.ing refractory, forming the Al_(2)O_(3) or Mg O·Al_(2)O_(3). The slag had a significant acceleration effect on the mass transfer. The mass transfer rate(or the reaction rate) of the system with the slag was approximately 5 times larger than that of the system without the slag. In the first 20 min of the refining, rates of magnesium mass transfer at the steel/inclusion interface, steel/refractory interface, and steel/slag interface were x, 1.1 x, and 2.2 x,respectively. The composition transformation of inclusions and the mass transfer of magnesium and aluminum in the steel were predicted with an acceptable accuracy using the establi.hed kinetic model.

关键词： mass transfer steel slag li.ing refractory nonmetalli. inclusions kinetic model

Understanding urban structures and crowd dynamics leveraging large-scale vehicle mobili.y data

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Frontiers of Computer Science 2020年第5期14卷 77-88页

作者： Zhihan Jiang Yan li. Xiaoli.ng Fan cheng Wang Jonathan li.Longbiao Chen Fujian Key Laboratory of Sensing and Computing for Smart Cities School of Information Science and EngineeringXiamen UniversityXiamen361005China

A comprehensive understanding of city structures and urban dynamics can greatly improve the efficiency and quali.y of urban planning and management,while the traditional approaches of which,such as manual surveys,usually incur substantial labor and *** this paper,we propose a data-driven framework to sense urban structures and dynamics from large-scale vehicle mobili.y ***,we divide the city into fine-grained grids,and cluster the grids with similar mobili.y features into structured urban areas with a proposed distance-constrained clustering algorithm(DCCA).Second,we detect irregular mobili.y traffic patterns in each area leveraging an ARIMA-based anomaly detection algorithm(ADAM),and correlate them to the urban social and emergency ***,we build a visuali.ation system to demonstrate the urban structures and crowd *** evaluate our framework using real-world datasets collected from Xiamen city,China,and the results show that the proposed framework can sense urban structures and crowd comprehensively and effectively.

关键词： vehicle mobili.y big data spatial clustering event detection urban computing ubiquitous computing