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太平洋十年涛动对全球地表气温变化的影响足迹

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Science Bulletin 2024年第4期69卷 445-448页

作者：梁莉莉 Alan D.ziegler 陈德亮 Philippe Ciais 李肇新梁时婧王大山徐荣嵘曾振中 School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen 518055China SUSTech Energy Institute for Carbon Neutrality Southern University of Science and TechnologyShenzhen 518055China Faculty of Fisheries Technology and Aquatic Resources Mae Jo UniversityChiang Mai 50000Thailand Regional Climate Group Department of Earth SciencesUniversity of GothenburgGothenburg 40530Sweden Laboratoire des Sciences du Climat et de l’Environnement UniversitéParis-SaclayGif-sur-Yvette 91191France Laboratoire de Météorologie Dynamique Centre national de la recherche scientifiqueSorbonne UniversitéÉcole Normale SupérieureÉcole PolytechniqueParis 75000France Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control School of Environmental Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China

Sea surface temperature modes have been found to modulate anthropogenic global warming rates on annual and decadal timescales,sometimes leading to periods of“slowdown”despite increasing greenhouse gas emissions^([1]).

关键词：太平洋十年涛动地表气温 greenhouse

miniSCIDOM: a scintillator-based tomograph for volumetric dose reconstruction of single laser-driven proton bunches

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High Power Laser Science and Engineering 2024年第2期12卷 41-50页

作者： A.Corvino M.Reimold E.Beyreuther F.-E.Brack F.Kroll J.Pawelke J.D.Schilz M.Schneider U.Schramm M.E.P.Umlandt K.Zeil T.ziegler J.Metzkes-Ng Helmholtz-Zentrum Dresden–Rossendorf DresdenGermany Technische Universität Dresden DresdenGermany OncoRay–National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav CarusTUD Dresden University of TechnologyHelmholtz-Zentrum Dresden–RossendorfDresdenGermany Current affiliation:Institut Curie UniversitéPSLCNRS UMR3347OrsayFrance Current affiliation:Universitätsklinikum Freiburg FreiburgGermany

Laser plasma accelerators(LPAs)enable the generation of intense and short proton bunches on a micrometre scale,thus offering new experimental capabilities to research fields such as ultra-high dose rate radiobiology or material *** spectrally broadband,laser-accelerated proton bunches allow for tailored volumetric dose deposition in a sample via single bunches to excite or probe specific sample *** rising number of such experiments indicates a need for diagnostics providing spatially resolved characterization of dose distributions with volumes of approximately 1 cm^(3) for single proton bunches to allow for fast online *** we present the scintillator-based miniSCIDOM detector for online single-bunch tomographic reconstruction of dose distributions in volumes of up to approximately 1 cm^(3).The detector achieves a spatial resolution below 500μm and a sensitivity of 100 *** detector performance is tested at a proton therapy cyclotron and an LPA proton *** experiments’primary focus is the characterization of the scintillator’s ionization quenching behaviour.

关键词： beam monitoring detectors laser-driven proton beams scintillator-based diagnostics ultra-high dose rate

Nano-Morphology of a Polymer Electrolyte Fuel Cell Catalyst Layer Imaging, Reconstruction and Analysis

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Nano Research 2011年第9期4卷 849-860页

作者： Simon Thiele Roland Zengerle Christoph ziegler Laboratory for MEMS Applications Department of Microsystems Engineering--IMTEK University of Freiburg Georges-Koehler-Allee106 79110 Freiburg Germany

The oxygen reduction reaction （ORR） in the cathode catalyst layer （CCL） of polymer electrolyte fuel cells （PEFC） is one of the major causes of performance loss during operation. In addition, the CCL is the most expensive component due to the use of a Pt catalyst. Apart from the ORR itself, the species transport to and from the reactive sites determines the performance of the PEFC. The effective transport properties of the species in the CCL depend on its nanostructure. Therefore a three-dimensional reconstruction of the CCL is required. A series of two-dimensional images was obtained from focused ion beam- scanning electron microscope （FIB-SEM） imaging and a segmentation method for the two-dimensional images has been developed. The pore size distribution （PSD） was calculated for the three-dimensional geometry. The influence of the alignment and the anisotropic pixel size on the PSD has been investigated. Pores were found in the range between 5 nm and 205 nm. Evaluation of the Knudsen number showed that gas transport in the CCL is governed by the transition flow regime. The liquid water transport can be described within continuum hydrodynamics by including suitable slip flow boundary conditions.

关键词： Cathode catalyst layer (CCL), polymer electrolyte fuel cell (PEFC), tomograph three-dimensional reconstruction

Chronic Hyperinsulinism Induced Down-regulation of Insulin Post-Receptor Signaling Transduction in Hep G2 Cells

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Journal of Huazhong University of Science and Technology(Medical Sciences) 2002年第4期22卷 313-316页

作者：袁莉 Reinhard ziegler Andreas Hamann DepartmentofEndocrinologyandMetabolism

To study the regulatory effect of acute and chronic insulin treatmenton insulin post- re- ceptor signaling transduction pathway in a human hepatom a cell line (Hep G2 ) ,Hep G2 cells were incubated in the presence or absence of insulin with different concentrations in serum free m edia for16 h and then stim ulated with10 0 nmol/ L insulin for1m *** levels of insulin receptor β- subunit(IRβ) ,insulin receptor substrate- 1(IRS- 1) and p85 subunit of phosphatidylinositol3- kinase(PI3- kinase) were determined in total cell lysates by Western- im ***- ed proteins IRβ,IRS- 1and interaction of PI3- kinase with IRS- 1were determ ined by im munopre- *** showed that 1- min insulin stimulation rapidly induced tyrosine phosphorylation of IRβ and IRS- 1,which in turn,resulting in association of PI 3- kinase with IRS- 1.1- 10 0 nm ol/ L chronic insulin treatment induced a dose- dependent decrease in the protein level of IRβ and a slight decrease in the protein level of IRS- *** was a m ore marked reduction in the phospho- rylation of IRβ,IRS- 1,reaching a nadir of2 2 % (P<0 .0 1) and15 % (P<0 .0 1) of control lev- els,respectively,after16 h treatment with 10 0 nm ol/ L *** association between IRS- 1 and PI3- kinase was decreased by6 6 % (P<0 .0 1) .There was no significant change in PI3- ki- nase protein levels. These data suggest that chronic insulin treatm ent can induce alterations of IRβ,IRS- 1and PI 3- kinase three early steps in insulin action,which contributes significantly to insulin resistance,and may account for desensitization of insulin action.

关键词： insulin insulin signaling transduction insulin resistance

Numerical studies of the Kelvin-Hemholtz instability in a coronal jet

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Research in Astronomy and Astrophysics 2018年第4期18卷 91-104页

作者： Tian-Le Zhao Lei Ni Jun Lin Udo ziegler Yunnan Observatories Chinese Academy of Sciences Kunming 650216 China University of Chinese Academy of Sciences Beijing 100049 China Center for Astronomical Mega-Science Chinese Academy of Sciences Beijing 100101 China Leibniz-Institut fur Astrophysik Potsdam Potsdam D-14482 Germany

Kelvin-Hemholtz（K-H）instability in a coronal EUV jet is studied via 2.5D MHD numerical *** jet results from magnetic reconnection due to the interaction of the newly emerging magnetic field and the pre-existing magnetic field in the *** results show that the Alfv e′n Mach number along the jet is about 5–14 just before the instability occurs,and it is even higher than 14 at some local *** the K-H instability process,several vortex-like plasma blobs with high temperature and high density appear along the jet,and magnetic fields have also been rolled up and the magnetic configuration including anti-parallel magnetic fields forms,which leads to magnetic reconnection at many X-points and current sheet fragments inside the vortex-like *** magnetic islands appear inside the main current sheet,the total kinetic energy of the reconnection outflows decreases,and cannot support the formation of the vortex-like blob along the jet any longer,then the K-H instability eventually *** also present the results about how the guide field and flux emerging speed affect the K-H *** find that a strong guide field inhibits shock formation in the reconnecting upward outflow regions but helps secondary magnetic islands appear earlier in the main current sheet,and then apparently suppresses the K-H *** the speed of the emerging magnetic field decreases,the K-H instability appears later,the highest temperature inside the vortex blob gets lower and the vortex structure gets smaller.

关键词： Sun corona jet — Kelvin-Hemholtz instability — guide-field — method numerical simulations

Numerical experiments of disturbance to the solar atmosphere caused by eruptions

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Science China(Physics,Mechanics & Astronomy) 2012年第7期55卷 1316-1329页

作者： MEI ZhiXing UDO ziegler LIN Jun Yunnan Astronomical Observatory Chinese Academy or'SciencesP.O.Box 110Kunming 650011China Graduate University of the Chinese Academy of Sciences Beijing 100049China Leibniz-lnstitut filer A strophysik Potsdam Potsdam D-14482Germany Harvard-Smithsonian Center for Astrophysics 60 Garden StreetCambridge 02138USA

Despite extensive research on various global waves in solar eruptions, debate continues on the intrinsic nature of them. In this work, we performed numerical experiments of the coronal mass ejection with emphases on the associated large-scale MHD waves. A fast-mode shock forms in front of the flux rope during the eruption with a dimming region following it, and the development of a three-component structure of the ejecta is observed. At the flank of the flux rope, the slow-mode shock and the velocity vortices are also invoked. The dependence of the eruption energetics on the strength of the background field and the coronal plasma density distribution is apparent： the stronger the background field is, and/or the lower the coronal plasma density is, the more energetic the eruption is. In the lower Alfven speed environment, the slow mode shock and the large scale velocity vortices may be the source of the EIT wave. In the high Alfvdn speed environment, on the other hand, the echo due to the reflection of the fast shock on the bottom boundary could be so strong that its interaction with the slow mode shock and the velocity vortices produces the second echo propagating downward and causing the secondary disturbance to the boundary surface. We suggest that this second echo, together with the slow shock and the velocity vortices, could constitute a possible candidate of the source for the EIT wave.

关键词： sun: coronal mass ejections sun: flares sun: magnetic fields plasmas: MHD waves plasma: shock waves

The Ellerman bomb and ultraviolet burst triggered successively by an emerging magnetic flux rope

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Research in Astronomy and Astrophysics 2021年第9期21卷 163-179页

作者： Guan-Chong Cheng Lei Ni Ya-Jie Chen Udo ziegler Jun Lin Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China CAS Key Laboratory of Solar Activity National Astronomical ObservatoriesBeijing 100101China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100101China School of Earth and Space Sciences Peking UniversityBeijing 100871China Astrophysikalisches Institut Potsdam D-14482 Potsdam Germany

Ellerman bombs(EBs)and ultraviolet(UV)bursts are common brightening phenomena,which are usually generated in the low solar atmosphere of emerging flux *** this paper,we have investigated the emergence of an initial un-twisted magnetic flux rope based on three-dimensional(3 D)magneto-hydrodynamic(MHD)*** EB-like and UV burst-like activities successively appear in the U-shaped part of the undulating magnetic fields triggered by the Parker *** EB-like activity starts to appear earlier and lasts for about 80 *** minutes later,a much hotter UV burstlike event starts to appear and lasts for about 60 *** the direction vertical to the solar surface,both the EB and UV burst start in the low chromosphere,but the UV burst extends to a higher altitude in the up *** regions with apparent temperature increase in the EB and UV burst are both located inside the small twisted flux ropes generated in magnetic reconnection processes,which are consistent with the previous 2 D simulations that most hot regions are usually located inside the magnetic ***,the twisted flux rope corresponding to the EB is only strongly heated after it floats up to an altitude much higher than the reconnection site during that *** analyses show that the EB is heated by the shocks driven by the strong horizontal flows at two sides of the U-shaped magnetic *** twisted flux rope corresponding to the UV burst is heated by the driven magnetic reconnection process.

关键词： magnetic reconnection (magnetohydrodynamics)MHD shocks Sun:heating Sun:low solar atmosphere Sun:magnetic flux emergence

Estimation of sediment sources using selected chemical tracers in the Perry lake basin,Kansas,USA

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International Journal of Sediment Research 2009年第1期24卷 108-125页

作者： K. E. JURACEK A. C. ziegler Hydrologist U.S. Geological Survey 4821 Quail Crest Place Lawrence KS USA 66049

The ability to achieve meaningful decreases in sediment loads to reservoirs requires a determination of the relative importance of sediment sources within the contributing basins. In an investigation of sources of fine-grained sediment(clay and silt) within the Perry Lake Basin in northeast Kansas,representative samples of channel-bank sources,surface-soil sources(cropland and grassland),and reservoir bottom sediment were collected,chemically analyzed,and compared. The samples were sieved to isolate the <63 μ m fraction and analyzed for selected nutrients(total nitrogen and total phosphorus),organic and total carbon,25 trace elements,and the radionuclide cesium-137(137Cs). On the basis of substantial and consistent compositional differences among the source types,total nitrogen(TN),total phosphorus(TP),total organic carbon(TOC),and 137Cs were selected for use in the estimation of sediment sources. To further account for differences in particle-size composition between the sources and the reservoir bottom sediment,constituent ratio and clay-normalization techniques were used. Computed ratios included TOC to TN,TOC to TP,and TN to TP. Constituent concentrations(TN,TP,TOC) and activities(137Cs) were normalized by dividing by the percentage of clay. Thus,the sediment-source estimations involved the use of seven sediment-source indicators. Within the Perry Lake Basin,the consensus of the seven indicators was that both channel-bank and surface-soil sources were important in the Atchison County Lake and Banner Creek Reservoir subbasins,whereas channel-bank sources were dominant in the Mission Lake subbasin. On the sole basis of 137Cs activity,surface-soil sources contributed the most fine-grained sediment to Atchison County Lake,and channel-bank sources contributed the most fine-grained sediment to Banner Creek Reservoir and Mission Lake. Both the seven-indicator consensus and 137Cs indicated that channel-bank sources were dominant for Perry Lake and that channel-bank sour

关键词： Sediment Source Tracer Perry Lake Kansas

The TRANSMED Atlas： geological-geophysical fabric of the Mediterranean region——Final report of the project

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Episodes 2004年第4期27卷 244-254页

作者： WilliamCavazza FrancoisRoure WimSpakman GèrardM.Stampfli PeterA.ziegler DepartmentofEarthandGeoenvironmentalSciences UniversityofBolognaItaly InstitutFrancaisduPetrole Rueil-MalmaisonFrance FacultyofEarthSciences UniversityofUtrechtTheNetherlands DepartmentofEarthSciences UniversityofLausanneSwitzerland DepartmentofGeosciences UniversityofBaselSwitzeland

Geological research on the Mediterranean region is presently characterized by the transition from disciplinary to multidisciplinary research, as well as from national to international investigations. In order to synthesize and integrate the vast disciplinary and national datasets which are available, it is necessary to implement maximum interaction among geoscientists of different backgrounds. The creation of project-oriented task forces in universities and other research institutions, as well as the development of large international cooperation programs, is instrumental in pursuing such a multidisciplinary and supranational approach. The TRANSMED Atlas, an official publication of the 32nd International Geological Congress (Florence 2004), is the result of an international scientific cooperation program which brought together for over two years sixtythree structural geologists, geophysicists, marine geologists, petrologists, sedimentologists, stratigraphers, paleogeographers, and petroleum geologists coming from eighteen countries, and working for the petroleum industry, academia, and other institutions, both public and private. The TRANSMED Atlas provides an updated, synthetic, and coherent portrayal of the overall geological-geophysical structure of the Mediterranean domain and the surrounding areas. The initial stimulus for the Atlas came from the realization of the extremely heterogeneous nature of the existing geological-geophysical data about such domain. These data have been gathered by universities, oil companies, geological surveys and other institutions in several countries, often using different procedures and standards. In addition, much of these data are written in languages and published in outlets that are not readily accessible to the general international reader. By synthesizing and integrating a wealth of preexisting and new data derived from surficial geology, seismic sections at various scales, and mantle tomographies, the TRANSMED Atlas provide

关键词：地质构造地中海地球物理学海洋沉降