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Chinese Science Bulletin 2013年第23期58卷 2883-2892页

作者： QIU BingWen ZHONG Ming TANG ZhengHong CHEN ChongCheng Key Laboratory of Spatial Data Mining & Information Sharing of Ministry of Education Spatial Information Research Centre of Fujian Province Community and Regional Planning Program University of Nebraska-Lincoln

Understanding the seasonal behaviour of a subtropical forest and its inter-annual variation is crucial to understanding and monitoring its ecosystem function in the context of global warming. Based on the Moderate Resolution Imaging Spectroradiometer (MODIS) Enhanced Vegetation Index dataset, a wavelet transform method was used to investigate the inter-annual variations of vegetation phenology in a subtropical mountain and hill region in Fujian, China, during 2001-2010. The results show a distinct inter-annual variation of vegetation phenology related to climate variability even if most areas presented non-significant trends. The start dates significantly advanced and end dates delayed in 2003 and 2008, due to anomalously warm conditions. There was generally a gradient of increasing start dates, and earlier end dates of vegetation growing season, due to colder temperatures at higher altitudes. However, the altitudinal phenology relationship also depends on its corresponding rainfall conditions. Earlier start dates were observed at higher altitudes during rainfall deficit years such as 2008, which coincides with relatively abundant rainfall at higher altitudes. This paper reveals that vegetation phenology was coupled with altitudinal gradient, with distinct responses at different combinations of alternate temperature and precipitation conditions variability.

关键词：全球气候变暖植被物候亚热带山地丘陵地区时空变异海拔高度中国中分辨率成像光谱仪

The Southern Hemisphere sudden stratospheric warming of September 2019

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Science Bulletin 2020年第21期65卷 1800-1802,M0003页

作者： Xiaocen Shen Lin Wang Scott Osprey Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Atmospheric Oceanic and Planetary PhysicsUniversity of OxfordOxford OX13PUUK National centre for Atmospheric Science University of OxfordOxford OX13PUUK

Sudden stratospheric warmings(SSWs)are extreme cases of stratospheric polar vortex weakening[1].They are termed minor when a reversal of the stratospheric meridional temperature gradient in the subpolar region at 10 hPa and poleward of 60occurs,or major when this is accompanied by a complete reversal of the stratospheric circumpolar westerly jet[2].Although SSWs occur in both hemispheres,major SSWs are usually observed in the Northern Hemisphere,with a frequency of approximately six per *** contrast,only one major SSW has been recorded in the Southern Hemisphere,which occurred in 2002[3].

关键词：观测记录南极臭氧洞波流相互作用科学证据南极地区

Paleoarchean bedrock lithologies across the Makhonjwa Mountains of South Africa and Swaziland linked to geochemical,magnetic and tectonic data reveal early plate tectonic genes flanking subduction margins

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Geoscience Frontiers 2018年第3期9卷 603-665页

作者： Maarten de Wit Harald Furnes Scott MacLennan Moctar Doucouré Blair Schoene Ute Weckmann Uma Martinez Sam Bowring AEON-ESSRI (Africa Earth Observatory Network-Earth Stewardship Science Research Institute) Nelson Mandela University Department of Earth Science & centre for Geobiology University of Bergen Department of Geosciences Princeton University Department of Geosciences Nelson Mandela University Department Geophysics GFZ-German Research Centre for GeosciencesHelmholtz Centre GISCAPETOWN Earth Atmosphere and Planetary SciencesMassachusetts Institute of Technology

The Makhonjwa Mountains, traditionally referred to as the Barberton Greenstone Belt, retain an iconic Paleoarchean archive against which numerical models of early earth geodynamics can be tested. We present new geologic and structural maps, geochemical plots, geo- and thermo-chronology, and geophysical data from seven silicic, mafic to ultramafic complexes separated by major shear systems across the southern Makhonjwa Mountains. All reveal signs of modern oceanic back-arc crust and subductionrelated processes. We compare the rates of processes determined from this data and balance these against plate tectonic and plume related models. Robust rates of both horizontal and vertical tectonic processes derived from the Makhonjwa Mountain complexes are similar, well within an order of magnitude, to those encountered across modern oceanic and orogenic terrains flanking Western Pacific-like subduction zones. We conclude that plate tectonics and linked plate-boundary processes were well established by 3.2-3.6 Ga. Our work provides new constraints for modellers with rates of a 'basket' of processes against which to test Paleoarchean geodynamic models over a time period close to the length of the Phanerozoic.

关键词： Paleoarchean Barberton Greenstone Belt Onverwacht Suite Geologic bedrock and structural maps Geochemistry and geophysics Plate tectonics

Determination and Validation of Markers for Heat-Induced Damage in Wool Proteins

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American Journal of Analytical Chemistry 2012年第6期3卷 431-436页

作者： Anita J. Grosvenor James D. Morton Jolon M. Dyer Department of Wine Food and Molecular Biosciences Lincoln University Lincoln New Zealand Food and Bio-based Products Lincoln Research Centre AgResearch Lincoln New Zealand The Biomolecular Interaction centre University of Canterbury Christchurch New Zealand

Protein-based animal fibres of commercial importance are frequently exposed to elevated temperatures during processing treatments. Hydrothermal processes cause protein deterioration, impacting negatively on the value or condition of these materials. This study was designed to investigate hydrothermal damage in wool proteins at the molecular level. The effect of hydrothermal damage on Type I and II intermediate filament proteins (keratins) extracted from wool was characterised using advanced quantitative techniques based on isobaric iTRAQ labelling and mass spectrometry. Many native peptides were observed to be degraded and modified. Amongst these, twenty keratin peptides were observed to consistently degrade during hydrothermal exposure. These peptides acted as molecular markers of damage – specific indicators of the extent of heat-induced protein damage. This technology will be of value in assessing the severity of damage imparted after high temperature exposure of protein-based animal fibres such as wool and cashmere during processes such as dyeing and carbonising, or even after high temperature human hair treatments. The identification of molecular damage markers identified within wool and other materials provides a new route to sensitive and specific evaluation of the effects of protein deterioration. It is anticipated that the utilisation of such markers will facilitate the development of targeted approaches to minimising processing damage to high-value fibres and protein-based biomaterials.

关键词： Wool Proteins Protein Damage Molecular Markers Mass Spectrometry Hydrothermal Heat

New Candidate Massive Clusters from 2MASS

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International Journal of Astronomy and Astrophysics 2013年第2期3卷 161-173页

作者： Dirk Froebrich centre for Astrophysics and planetary Science University of Kent Canterbury UK

Massive stars are important for the evolution of the interstellar medium. The detailed study of their properties (such as mass loss, rotation, magnetic fields) is enormously facilitated by samples of these objects in young massive galactic star clusters. Using 2MASS we have searched for so far unknown candidates of red supergiant clusters along the Galactic Plane. Utilising deep high resolution UKIDSS GPS and VISTA VVV data to study colour-magnitude diagrams, we uncover six new massive cluster candidates in the inner Galaxy. If spectroscopically confirmed as real clusters, two of them could be part of the Scutum-Complex. One cluster candidate has a number of potential red supergiant members comparable to RSGC1 and 3. Our investigation of UKIDSS data reveals for the first time the main sequence of the massive cluster RSGC2. The stars of the sequence show an increased projected density at the same position as the known red supergiants in the cluster and have E(J-K) = 1.6 mag. This either indicates an unusual extinction law along the line of sight or a much lower near infrared extinction to the cluster than previously estimated in the literature. We suggest that psf-photometry in UKIDSS images might be able to uncover the main sequence of other RSGC clusters.

关键词： Open Clusters and Associations General Galaxies Star Clusters

The Asymmetric Connection of SST in the Tasman Sea with Respect to the Opposite Phases of ENSO in Austral Summer

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Advances in Atmospheric Sciences 2022年第11期39卷 1897-1913页

作者： Xueqian SUN Shuanglin LI Stefan LIESS Climate Change Research Center(CCRC) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Department of Atmospheric Science/centre for Severe Weather and Climate and Hydro-geological Hazards China University of GeosciencesWuhan 430074China College of Earth and planetary Science University of Chinese Academy of SciencesBeijing 100049China Department of Soil Waterand ClimateUniversity of MinnesotaTwin CitiesSt.Paul MN 55108MinnesotaUSA

This study uses linear regression and composite analyses to identify a pronounced asymmetric connection of sea surface temperature(SST)in the Tasman Sea with the two opposite phases of El Ni?o-Southern Oscillation(ENSO)during austral *** El Ni?o years,the SST anomalies(SSTAs)in the Tasman Sea exhibit a dipolar pattern with weak warmth in the northwest and modest cooling in the southeast,while during La Ni?a years the SSTAs exhibit a basin-scale warmth with greater *** into the underlying mechanism suggest that this asymmetry arises from a mechanism related to oceanic heat transport,specifically the anomalous Ekman meridional heat transport induced by the zonal wind stress anomalies,rather than the surface heat fluxes on the air-sea *** analysis reveals that the asymmetry of oceanic heat transport between El Ni?o and La Ni?a years is driven by the asymmetric atmospheric circulation over the Tasman Sea stimulated by the asymmetric diabatic heating in the tropical Pacific between the two opposite ENSO phases.

关键词： El Ni?o-Southern Oscillation SST in the Tasman Sea asymmetric connection surface heat fluxes oceanic heat transport

A Study of the Truncated Square Pyramid Geometry for Enhancement of Super-hydrophobicity

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Journal of Bionic Engineering 2020年第4期17卷 843-850页

作者： Wei Gong Yangang Wang Yiyi Chen Xiang Li Kongjing Li Zhongxu Wang Yuying Yan R&D centre:Semiconductors Dynex Semiconductor Ltd.Doddington RoadLincolnLN63LFUK Fluids and Thermal Engineering Research Group Faculty of EngineeringUniversity of NottinghamNottinghamNG72RDUK

Super-hydrophobic surfaces are quite common in nature,inspiring people to continually explore its water-repellence property and applications to our *** has been generally agreed that the property of super-hydrophobicity is mainly contributed by the microscale or nanoscale(or even smaller)architecture on the ***,there is an energy barrier between the Cassie-Baxter wetting state and the Wenzel wetting *** optimized square post micro structure with truncated square pyramid geometry is introduced in this work to increase the energy barrier,enhancing the robustness of *** analysis is conducted based on the wetting transition energy *** simulation based on a phase-field lattice Boltzmann method is carried out to verify the theoretical *** numerical simulation agrees well with the theoretical analysis,showing the positive significance of the proposed micro ***,another novel micro structure of rough surface is presented,which combines the advantages of truncated pyramid geometry and noncommunicating roughness *** analysis shows that the novel micro structure of rough surface can effectively hinder the Cassie-Baxter state to Wenzel state transition,furthefly enhancing the robustness of the surface hydrophobicity.

关键词： truncated square pyramid geometry wetting transition energy barrier super-hydrophobicity lattice Boltzmann method

Testing optically stimulated luminescence dating on sand-sized quartz of deltaic deposits from the Sperchios delta plain, central Greece

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Journal of Palaeogeography 2018年第2期7卷 130-145页

作者： Evangelos Tsakalos Elias Dimitriou Maria Kazantzaki Christos Anagnostou John Christodoulakis Eleni Filippaki Hellenic centre for Marine Research Institute of Inland Waters Laboratory of Archaeometry Institute of Nanoscience and Nanotechnology National Centre for Scientific Research N.C.S.R. "Demokritos" Department of Geophysics Division of Earth and Planetary Sciences Graduate School of Science Kyoto University Hellenic centre of Marine Research Institute of Oceanography Climate Research Group Division of Environmental Physics and Meteorology Faculty of Physics National and Kapodistrian University of Athens

This study reports on the first investigation into the potential of luminescence dating to establish a chronological framework for the depositional sequences of the Sperchios delta plain, central Greece. A series of three borehole cores(20 m deep) and two shallow cores(4 m deep), from across the delta plain, were extracted, and samples were collected for luminescence dating. The luminescence ages of sand-sized quartz grains were obtained from small aliquots of quartz, using the Single-Aliquot Regenerative-dose(SAR) *** equivalent dose determination included a series of tests and the selection of the Minimum Age Model(MAM) as the most appropriate statistical model. This made it possible to confirm the applicability of quartz Optically Stimulated Luminescence(OSL) dating to establish absolute chronology for deltaic sediments from the Sperchios delta *** age results of the five cores showed that the deltaic sediments were deposited during the Holocene.A relatively rapid deposition is implied for the top14 m possibly as a result of the deceleration in the rate of the sea-level rise and the transition to terrestrial conditions, while on the deeper parts, the reduced sedimentation rate may indicate a lagoonal or coastal environment.

关键词： Luminescence dating Holocene Sedimentation rates Deltaic deposits Sperchios delta plain Central Greece

Lower-order zonal gravitational coefficients caused by zonal circulations inside gaseous planets: Convective flows and numerical comparison between modeling approaches

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Earth and planetary Physics 2020年第2期4卷 89-94页

作者： DaLi Kong KeKe Zhang Key Laboratory of planetary Sciences Shanghai Astronomical ObservatoryChinese Academy of Sciences80 Nandan RoadShanghai 200030China State Key Laboratory of Lunar and planetary Sciences Macao University of Science and TechnologyTaipaMacao S.A.RChina centre for Geophysical and Astrophysical Fluid Dynamics College of EngineeringMathematics and Physical SciencesUniversity of ExeterNorth Park RoadExeterEX44QFUK

To infer the internal equilibrium structure of a gaseous planet, especially the equation of state(EOS) and size of its inner core,requires accurate determination of lower-order zonal gravitational coefficients. Modeling of the gravitational signature associated with deep zonal circulation depends critically upon reliable subtraction of the dynamical components from totally derived gravitational coefficients. In the era of the Juno mission and the Grand Finale phase of the Cassini mission, it is timely and necessary to revisit and examine the so-called ‘Thermal Wind Equation(TWE)’, which has been extensively utilized to diagnose the dynamical parts of the gravitational fields measured by the two spacecrafts. TWE treats as negligible a few terms in the full equation of balance. However, the self-gravitational anomaly of the distorted fluid, unlike oblateness effects of solid-body rotation, is not a priori minor and thus should not be neglected in the name of approximation. Another equation, the ‘Thermal Gravitational Wind Equation(TGWE)’, includes this important additional term;we compare it with the TWE and show that physically the TGWE models a fundamentally different balance from the TWE and delivers numerical results considerably different from models based on the TWE. We conclude that the TWE balance cannot be relied upon to produce realistic convection models. Only after the TGWE balance is obtained can the relative importance of terms be *** calculations we report here are based on two types of zonal circulations that are produced by realistically possible convections inside planets, instead of being constructed or assumed.

关键词： gaseous planets gravitation zonal circulation

Grenvillian orogeny in the Southern Cathaysia Block:Constraints from U-Pb ages and Lu-Hf isotopes in zircon from metamorphic basement

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Chinese Science Bulletin 2008年第19期53卷 3037-3050页

作者： WANG LiJuan YU JinHai S.Y. O'REILLY W.L. GRIFFIN SUN Tao WEI ZhenYang JIANG ShaoYong SHU LiangShu State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 210093 China GEMOC National Key centre Department of Earth and Planetary Science Macquarie University Sydney NSW 2109 Australia

Metamorphic basement rocks in the Cathaysia Block are composed mainly of meta-sediments with different ages. New zircon U-Pb geochronological results from the meta-sedimentary rocks exposed in the Zengcheng and Hezi areas, southern Cathaysia Block, show that they consist dominantly of early Neoproterozoic (1.0―0.9 Ga) materials with minor Paleo- to Mesoproterozoic and late Neoproterozoic (0.8―0.6 Ga) components, suggesting that the detritus mostly come from a Grenvillian orogen. The youngest detrital zircon ages place a constraint on the deposition time of these sediments in Late Neoproterozoic. Zircon Hf isotopic compositions indicate that the Grenvillian zircons were derived from the reworking of Mesoproterozoic arc magmatic rocks and Paleoproterozoic continental crust, implying an arc-continent collisional setting. Single-peak age spectra and the presence of abundant euhedral Grenvillian zircons suggest that the sedimentary provenance is not far away from the sample location. Thus, the Grenvillian orogen probably preexisted along the southern margin of the Cathaysia Block, or very close to the south. Similarity in the ages of Grenvillian orogeny and the influence of the assembly of Gondwana in South China with India and East Antarctic are discussed, with suggestion that South China was more likely linked with the India-East Antarctica continents in Early Neoproterozoic rather than between western Laurentia and eastern Australia.

关键词：华夏古大陆格伦维尔期锆石同位素新元古代