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On generation source sites of internal waves in the Luzon Strait

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Acta Oceanologica Sinica 2008年第3期27卷 38-50页

作者： zheng Quanan SONG y Tony LIN Hui HU Xiaomin MENG Junmin WANG Dan Department of Atmospheric and Oceanic Science University of Maryland College Park Maryland USA Jet Propulsion Laboratory California Institute of Technology Pasadena California USA Institute of Space and Earth Information Sciences The Chinese University of Hong Kong Hong Kong China First Institute of Oceanography. State Oceanic Administration. Oingdao 266061. China

This effort aims to determine the generation source sites in the Luzon Strait for energetic, long-crest, transbasin internal waves （IW） observed in the northern South China Sea （NSCS）. The roles of islands distributed on eastern side of the strait, Kuroshio, submarine ridges, shoaling thennocline, and strait configuration played in the IW generation are examined using the cruise data analysis, satellite data interpretation, and dynamical analysis. The islands and channels on eastern side of the strait are excluded from a list of possible IW source sites owing to their unmatched horizontal dimensions to the scale of IW crest line length, and the relative low Reynolds number. The Kuroshio has a potential to be a radiator for the long-crest IW disturbances, meanwhile, the Kurosbio west （east） wing absorbs the eastward （westward） propagating IW disturbance. Namely, the Kuroshio blockades the outside west-east propagating IW disturbances. The 3-D configuration of the Luzon Strait is characterized by a sudden, more than one order widening of the cross-section areas at the outlets on both sides, providing a favorable condition for IW type initial disturbance formation. In the Luzon Strait, the thermocline is featured by a westward shoaling all the year around, providing the dynamical conditions for the amplitude growth （declination） to the westward （eastward） propagating IW type disturbance. Thus, the west slope of western submarine ridge at the western outlet of the Luzon Strait is a high possibility source sites for energetic, long-crest, transbasin IWs in the NSCS. The interpretation results of satellite SAR images during a 13 a period from 1995 to 2007 provide the convincing evidence for the conclusions.

关键词： ocean internal waves solitary waves Luzon Strait satellite SAR image

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基于双目视觉技术的茶叶嫩芽定位方法研究

农机化研究 2025年第2期47卷 49-53页

作者：朱龙舜郑旻璐东南大学成贤学院南京210088 南京机电职业技术学院南京211306

进一步提升茶叶嫩芽定位的准确性及茶叶嫩芽采摘的作业效率,选取双目视觉技术作为切入点,针对其识别、定位、采摘等环节展开设计研究。考虑茶叶嫩芽采摘的基础特征和双目视觉技术的应用条件,合理搭建双目视觉模型,选用立体匹配的核心定... 详细信息

进一步提升茶叶嫩芽定位的准确性及茶叶嫩芽采摘的作业效率,选取双目视觉技术作为切入点,针对其识别、定位、采摘等环节展开设计研究。考虑茶叶嫩芽采摘的基础特征和双目视觉技术的应用条件,合理搭建双目视觉模型,选用立体匹配的核心定位算法,完成茶叶嫩芽的定位方法与采摘功能优化,并布置相应的试验机构,展开定位采摘验证试验。结果表明:基于双目视觉技术的茶叶嫩芽定位方法应用具有显著的优越性,较普通定位方法而言,识别误匹配率可降低至4.01%,平均漏采率为3.20%,嫩芽采摘完整率达93.40%,可以很好地促进茶叶嫩芽的后续处理加工,是采摘茶叶嫩芽的品质化的重要基础保障。

关键词：茶叶嫩芽定位双目视觉立体匹配采摘完整率品质化

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Trace-element of Tuoyun cli-nopyroxene:Implication for the deep processes of litho-spheric mantle beneath the southwest Tianshan,West China

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Chinese Science Bulletin 2001年第14期46卷 1206-1211页

作者： zheng Jianping LU Fengxiang S.y.O’Reilly LUO Zhaohua Faculty of Earth Sciences China University of GeosciencesWuhan 430074China Department of Earth and Planetary Sciences Macquarie UniversitySydneyNSW2109Australia Faculty of Earth Sciences China University of GeosciencesBeijing 100083China

Based on the LAM-ICPMS analytic results on the trace elements of clinopyroxenes in peridotitic xenoliths occurring in early-Cretaceous basalts from western Xinjiang, the properties and the deep processes, including partial melting and mantle metasomatism, of the subcontinental lithospheric mantle beneath the Tuoyun Basin are analyzed. In the northern edge of the Tarim Basin (southwest Tian-shan), the Mesozoic subcontinental lithosphere which has experienced the effect of partial melting (y Phanerozoic ’ocean-type’ mantle. The superposed influence of SiO2-un-saturated silicate melt and carbonate melt probably results in the metasomatic medium which resembles the hydrous silicated carbonate melt in some aspects. By comparing Tuoyun mantle with Cenozoic main mantle beneath eastern China, the properties are similar, while the former shows finer grain and higher diopside content of the peridotites and more conspicuous modal metasomatism.

关键词： west China mantle clinopyroxene LAM-ICPMS mantle heterogeneity deep process.

Taxuchin B,a New Chlorine-Containing Taxoid

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Chinese Chemical Letters 1997年第3期8卷 231-232页

作者： Fang, WS Fang, QC Liang, XT Lu, y Wu, N zheng, QT CHINESE ACAD MED SCI INST MAT MEDBEIJING 100050PEOPLES R CHINA BEIJING UNION MED COLL BEIJING 100050PEOPLES R CHINA

A new taxoid, taxuchin B[1], has been isolated from twigs and needles of Taxus chinensis. It is the first chlorine-containing taxoid reported to date.

关键词： Zhang Chen

Amyloid,tau,pathogen infection and antimicrobial protection in Alzheimer’s disease-conformist,nonconformist,and realistic prospects for AD pathogenesis

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Translational Neurodegeneration 2018年第1期7卷 362-377页

作者： Hongmei Li Chia-Chen Liu Hui zheng Timothy y.Huang Department of Neuroscience Mayo ClinicJacksonvilleFLUSA Huffington Center on Aging Baylor College of MedicineHoustonTXUSA Neuroscience Initiative Sanford Burnham Prebys Medical Discovery InstituteSan DiegoCAUSA

Background:Alzheimer’s disease(AD)is a fatal disease that threatens the quality of life of an aging population at a global *** hypotheses on the etiology of AD have been developed over the years to guide efforts in search of therapeutic *** body:In this review,we focus on four AD hypotheses currently relevant to AD onset:the prevailing amyloid cascade hypothesis,the well-recognized tau hypothesis,the increasingly popular pathogen(viral infection)hypothesis,and the infection-related antimicrobial protection *** briefly reviewing the main evidence supporting each hypothesis and discussing the questions that need to be addressed,we hope to gain a better understanding of the complicated multi-layered interactions in potential causal and/or risk factors in AD *** a defining feature of AD,the existence of amyloid deposits is likely fundamental to AD onset but is insufficient to wholly reproduce many complexities of the disorder.A similar belief is currently also applied to hyperphosphorylated tau aggregates within neurons,where tau has been postulated to drive neurodegeneration in the presence of pre-existing Aβplaques in the *** infection of the central nerve system by pathogens such as viruses may increase AD risk,it is yet to be determined whether this phenomenon is applicable to all cases of sporadic AD and whether it is a primary trigger for AD ***,the antimicrobial protection hypothesis provides insight into a potential physiological role for Aβpeptides,but how Aβ/microbial interactions affect AD pathogenesis during aging awaits further ***,this hypothesis cautions potential adverse effects in Aβ-targeting therapies by hindering potential roles for Aβin anti-viral ***:AD is a multi-factor complex disorder,which likely requires a combinatorial therapeutic approach to successfully slow or reduce symptomatic memory decline.A better understanding of how various causal a

关键词： Amyloid-beta Alzheimer’s disease Amyloid hypothesis Tau hypothesis Pathogen hypothesis Viral infection Antimicrobial protection

Structure evolution of the Fe_(3)C/Fe interface mediated by cementite decomposition in cold-deformed pearlitic steel wires

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Journal of Materials Science & Technology 2022年第6期101卷 28-36页

作者： y.T.Zhou X.H.Shao S.J.zheng X.L.Ma Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology School of Materials Science and EngineeringHebei University of TechnologyTianjin 300130China

Cold-drawn pearlitic steel wire is irreplaceably used in industry owing to its outstanding mechanical property which is dominated by the cementite/ferrite(Fe_(3)C/Fe) interfaces in the material. However, the fine structures of the Fe3C/Fe interfaces in the deformed wires are less known to date. In this work, transmission electron microscopic investigation was performed on the atomic structures of the interfaces with the Isaichev orientation relationship(OR) in the wires with progressive deformation strains. In addition to the effect of the dislocation/interface interactions, this work revealed that the deformation-induced partial decomposition of cementite plays an important role in the interface reconstruction during deformation. The interfacial carbon vacancies generated by cementite decomposition and particularly, the amorphization of cementite layers in the sample with ε > 1 could effectively.annihilated the interfacial dislocations and consequently relaxed the interfacial stress. The correlations between the interface structure changes and the mechanical properties of the wires were discussed.

关键词： Pearlitic steel Cementite decomposition Interface structure Deformation Transmission electron microscopy

Cascade degradation and electrocatalytic upcycling of waste poly(ethylene terephthalate)to valued products

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Nano Research 2025年第1期18卷 76-93页

作者： Xin Li Zirui Jiang Zongkui Kou John Wang Shiyou zheng School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China Department of Materials Science and Engineering National University of SingaporeSingapore 117574Singapore

The global annual production of poly(ethylene terephthalate)(PET)has reached 82 million tons,yet only a small fraction(less than 20%)is *** ultra-slow degradation rate of PET results in the accumulation of PET waste in the environment,causing serious plastic pollution and posing severe challenges to *** response,great efforts have been directed toward developing a cascade degradation and electrocatalytic upcycling strategy,which serves as a“waste-towealth”*** strategy involves electro-reforming PEThydrolyzed intermediates or using PET pyrolyzed products as electrocatalysts to generate high-value *** review provides an overview of the state-of-the-art strategies for the“degradation-electrocatalytic upcycling(De-eUp)”of PET ***,an introduction to the strategy is provided,categorizing it into two main frameworks:“pyrolysis-electrocatalytic upcycling”and“hydrolysis-electrocatalytic upcycling”.The section on“pyrolysis-electrocatalytic upcycling”delves into the degradation methods for designing derived carbon nanomaterials and their utilization as high-performance ***“hydrolysis-electrocatalytic upcycling”section discusses recent advancements in electro-reforming of PET hydrolyzed intermediates for the production of C_(1) and C_(2) *** review concludes by examining the challenges and future prospects in developing an efficient and economical PET upcycling *** is anticipated that this review will stimulate further progress in plastic waste valorization.

关键词： poly(ethylene terephthalate)waste electrocatalytic upcycling pyrolysis hydrolysis ethylene glycol oxidation reaction

Modelling the Dropout Patterns of MOOC Learners

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Tsinghua Science and Technology 2020年第3期25卷 313-324页

作者： zheng Xie the College of Liberal Arts and Sciences National University of Defense Technology

We conduct a survival analysis for the viewing durations of massive open online *** hazard function of the empirical duration data presents as a bathtub curve with the Lindy effect in its *** understand the evolutionary mechanisms underlying these features,we categorize learners into two classes based on their different distributions of viewing durations,namely lognormal distribution and power law with exponential *** random differential equations are provided to describe the growth patterns of viewing durations for the two classes *** expected duration change rate of the learners featured by lognormal distribution is supposed to be dependent on their past duration,and that of the remainder of learners is supposed to be inversely proportional to *** to the equations predict the features of viewing duration distributions,and those of the hazard *** equations also reveal the features of memory.and memorylessness for the respective viewing behaviors of the two classes.

关键词： data science applications in education distance education and online learning evaluation methodologies

Research trend of large-scale supercomputers and applications from the TOP500 and Gordon Bell Prize

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Science China(Information Sciences) 2020年第7期63卷 128-141页

作者： Weimin zheng Department of Computer Science and Technology Tsinghua University

China is playing an increasingly important role in international supercomputing. In highperformance computing domain, there are two famous awards: The TOP500 list for the fastest 500 supercomputers in the world and the Gordon Bell Prize for the best HPC(high-performance computing)applications. China has been awarded in both TOP500 list and Gordon Bell Prize. In this paper, we review the supercomputers in the latest TOP500 list and seven Gordon Bell Prize applications to show the research trend of the large-scale supercomputers and applications. The first trend we observe is that heterogeneous architectures are widely used in the construction of supercomputing systems. The second trend is that artificial intelligence applications are expected to become one of the main stream applications of *** third trend is that applying heterogeneous systems to complex scientific simulation applications will be more difficult.

关键词： TOP500 Gordon Bell Prize large-scale supercomputer