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Accelerating ions with high-energy short laser pulses from submicrometer thick targets

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High Power Laser Science and Engineering 2016年第4期4卷 1-8页

作者： f.wagner C.Brabetz O.Deppert M.Roth T.Stohlker An.Tauschwitz A.Tebartz B.Zielbauer V.Bagnoud GSI Helmholtzzentrum für Schwerionenforschung GmbH Helmholtz Institut Jena Institut für Kernphysik Technische Universitat Darmstadt Institute for Theoretical Physics Frankfurt University

Using the example of the PHELIX high-energy short pulse laser we discuss the technical preconditions to investigate ion acceleration with submicrometer thick targets. We show how the temporal contrast of this system was improved to prevent pre-ionization of such targets on the nanosecond timescale. furthermore the influence of typical fluctuations or uncertainties of the on-target intensity on ion acceleration experiments is discussed. We report how these uncertainties were reduced by improving the assessment and control of the on-shot intensity and by optimizing the positioning of the target into the focal plane. finally we report on experimental results showing maximum proton energies in excess of 85 MeV for ion acceleration via the target normal sheath acceleration mechanism using target thicknesses on the order of one micrometer.

关键词： high-power laser technique laser-ion acceleration relativistic laser plasma interaction target normal sheath acceleration temporal contrast

Geostatistical seismic inversion and 3D modelling of metric flow units,porosity and permeability in Brazilian presalt reservoir

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Petroleum Science 2024年第3期21卷 1699-1718页

作者： Rodrigo Penna wagner Moreira Lupinacci Exploratory Interpretation and Reservoir Characterization Group(GIECAR) Department of Geology and GeophysicsUniversidade Federal FluminenseNiteroiRJ24210-346Brazil Petrobras Rio de JaneiroRJ20031-912Brazil

flow units(fU)rock typing is a common technique for characterizing reservoir flow behavior,producing reliable porosity and permeability estimation even in complex geological ***,the lateral extrapolation of fU away from the well into the whole reservoir grid is commonly a difficult task and using the seismic data as constraints is rarely a subject of *** paper proposes a workflow to generate numerous possible 3D volumes of flow units,porosity and permeability below the seismic resolution limit,respecting the available seismic data at larger *** methodology is used in the Mero field,a Brazilian presalt carbonate reservoir located in the Santos Basin,who presents a complex and heterogenic geological setting with different sedimentological processes and diagenetic *** generated metric flow units using the conventional core analysis and transposed to the well log ***,given a Markov chain Monte Carlo algorithm,the seismic data and the well log statistics,we simulated acoustic impedance,decametric flow units(DfU),metric flow units(MfU),porosity and permeability volumes in the metric *** aim is to estimate a minimum amount of MfU able to calculate realistic scenarios porosity and permeability scenarios,without losing the seismic lateral *** other words,every porosity and permeability volume simulated produces a synthetic seismic that match the real seismic of the area,even in the metric *** achieved 3D results represent a high-resolution fluid flow reservoir modelling considering the lateral control of the seismic during the process and can be directly incorporated in the dynamic characterization workflow.

关键词： flowunits Geostatistical inversion Presalt reservoir 3D reservoir modelling Petrophysical modelling

Stochastic seismic inversion and Bayesian facies classification applied to porosity modeling and igneous rock identification

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Petroleum Science 2024年第2期21卷 918-935页

作者： fábio Júnior Damasceno fernandes Leonardo Teixeira Antonio fernando Menezes freire wagner Moreira Lupinacci Exploratory Interpretation and Reservoir Characterization Group(GIECAR) Department of Geology and GeophysicsFederal Fluminense UniversityNiter oiRJ24210-346Brazil Petrobras Rio de JaneiroRJ20231-030Brazil National Institute of Science and Technology of Petroleum Geophysics(INCT-GP/CNPQ) Niter oiRJ24210-346Brazil

We apply stochastic seismic inversion and Bayesian facies classification for porosity modeling and igneous rock identification in the presalt interval of the Santos Basin. This integration of seismic and well-derived information enhances reservoir characterization. Stochastic inversion and Bayesian classification are powerful tools because they permit addressing the uncertainties in the model. We used the ES-MDA algorithm to achieve the realizations equivalent to the percentiles P10, P50, and P90 of acoustic impedance, a novel method for acoustic inversion in presalt. The facies were divided into five: reservoir 1,reservoir 2, tight carbonates, clayey rocks, and igneous rocks. To deal with the overlaps in acoustic impedance values of facies, we included geological information using a priori probability, indicating that structural highs are reservoir-dominated. To illustrate our approach, we conducted porosity modeling using facies-related rock-physics models for rock-physics inversion in an area with a well drilled in a coquina bank and evaluated the thickness and extension of an igneous intrusion near the carbonate-salt interface. The modeled porosity and the classified seismic facies are in good agreement with the ones observed in the wells. Notably, the coquinas bank presents an improvement in the porosity towards the top. The a priori probability model was crucial for limiting the clayey rocks to the structural lows. In Well B, the hit rate of the igneous rock in the three scenarios is higher than 60%, showing an excellent thickness-prediction capability.

关键词： Stochastic inversion Bayesian classification Porosity modeling Carbonate reservoirs Igneous rocks

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制取生物表面活性剂的技术路线

日用化学工业译丛 1989年第4期 6-13页

作者： f.wagner 胡征宇

前言生物表面活性剂是由细菌、酵母和真菌等多种微生物产生的。基本上可分为五种主要类型: 1.糖脂 2.脂肽/脂蛋白 3.脂多糖 4.取代脂肪酸 5.磷脂最近Kosacic等综述了这些细胞外两亲代谢物的产生、性质及各种应用。生物表面活性剂的生物... 详细信息

前言生物表面活性剂是由细菌、酵母和真菌等多种微生物产生的。基本上可分为五种主要类型: 1.糖脂 2.脂肽/脂蛋白 3.脂多糖 4.取代脂肪酸 5.磷脂最近Kosacic等综述了这些细胞外两亲代谢物的产生、性质及各种应用。生物表面活性剂的生物合成常涉及微生物在烃类或其他亲脂性底物上的生长。生物表面活性剂在烃代谢中的生理作用与亲脂底物和微生物细胞间的起始作用机理有关。除烃外,油脂、甘油或碳水化合物等非烃类也可作为微生物合成生物活性剂的碳底物。视所用的微生物种类,合成过程可以是生长相关或非生长相关的。

关键词：生物表面活性剂微生物糖脂

Organic petrographic and mineralogical composition of the No. 6 coal seam of the Soutpansberg Coalfield, South Africa: Insights into paleovegetation and depositional environment

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International Journal of Coal Science & Technology 2024年第3期11卷 190-207页

作者： Sanki Biswas Nicola J.wagner Ofentse M.Moroeng DSI-NRf CIMERA/PPM Research Group Department of GeologyUniversity of JohannesburgJohannesburgSouth Africa

This study investigates the paleodepositional conditions of the No.6 Seam of the Madzaringwe formation in Makhado and Voorburg south area of the Soutpansberg Coalfield(Limpopo Province,South Africa)utilizing organic petrography and inorganic geochemical *** coals are predominantly high-volatile bituminous B-A rank with high ash yields(avg.36.1 wt%),characterized by high-vitrinite(~41.5 vol%),moderate-to-high inertinite(9.8 vol%–33.7 vol%)and low liptinite(~2.3 vol%).The distribution of inertinite varies among different coal horizons(from bottom-lower to middle-upper),suggesting differential oxidation conditions and/or paleofire ***-to-inertinite(V/I)ratio,tissue preservation–gelification index(TPI–GI),and groundwater–vegetation index(GWI–VI)plots,indicate that the peat-forming forest-swamp vegetation accumulated under mesotrophic-to-rheotrophic hydrological *** presence of structured macerals(i.e.,telinite,collotelinite,fusinite,and semifusinite)suggests well-preserved plant tissues,whereas framboidal pyrite and sulphur content(0.24 wt%–2.16 wt%)point to brackish-water influence at the peat *** coals contain quartz,kaolinite,siderite,muscovite,dolomite,calcite,and pyrite minerals,most of which were likely sourced from felsic igneous *** Al/(Al+fe+Mn)and(fe+Mn)/Ti ratios for the studied samples range between 0.24–0.97 and 0.57–70.10,*** ratios,Al–fe–Mn plot,and presence of massive botryoidal-type pyrite imply some influence of meteoric waters or fluids from hydrothermal activity ***,the chemical index of alteration(CIA:98.25–99.67),chemical index of weathering(CIW:92.04–97.66),and A–CN–K ternary diagram suggest inorganic matter suffered strong chemical weathering,indicating warm paleoclimatic conditions during the coal formation.

关键词： Macerals Coal facies Geochemical-indices Hydrothermal Madzaringwe formation Soutpansberg Coalfield

Light correcting light with nonlinear optics

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Advanced Photonics 2024年第2期6卷 41-49页

作者： Sachleen Singh Bereneice Sephton wagner Tavares Buono Vincenzo D'Ambrosio Thomas Konrad Andrew forbes University of the Witwatersrand School of Physics Università degli studi di Napoli “federico Ⅱ” Dipartimento di Fisica “E.Pancini” University of Kwa Zulu-Natal School of Chemistry and Physics

Structured light, where complex optical fields are tailored in all their degrees of freedom, has become highly topical of late, advanced by a sophisticated toolkit comprising both linear and nonlinear *** undesired structure from light is far less developed, leveraging mostly on inverting the distortion,e.g., with adaptive optics or the inverse transmission matrix of a complex channel, both requiring that the distortion be fully characterized through appropriate measurement. We show that distortions in spatially structured light can be corrected through difference-frequency generation in a nonlinear crystal without any need for the distortion to be known. We demonstrate the versatility of our approach using a wide range of aberrations and structured light modes, including higher-order orbital angular momentum(OAM) beams,showing excellent recovery of the original undistorted field. To highlight the efficacy of this process, we deploy the system in a prepare-and-measure communications link with OAM, showing minimal cross talk even when the transmission channel is highly aberrated, and outline how the approach could be extended to alternative experimental modalities and nonlinear processes. Our demonstration of light-correcting light without the need for measurement opens an approach to measurement-free error correction for classical and quantum structured light, with direct applications in imaging, sensing, and communication.

关键词： phase conjugation aberration correction orbital angular momentum nonlinear optics

Mechanical upper bowel obstruction caused by a large trichobezoar in a young woman: A very unusual case report

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World Journal of Clinical Cases 2024年第4期12卷 777-781页

作者： Magdalena Scherrer Peter Kornprat Robert Sucher Johanna Muehlsteiner Doris wagner Department of Surgery Division for GeneralVisceral and Transplantation SurgeryMedical University of GrazGraz 8036Austria Department of Surgery Clinic RohrbachRohrbach 4150Austria

BACKGROUND Bezoars usually compile human fibers and debris.A special form of bezoar in case of psychologically altered individuals is the *** consists of voluntarily swallowed hair bulks and is normally removed via *** leading to ileus have rarely been *** SUMMARY A 24-year-old female patient presented to the emergency room with abdominal pain,nausea,and vomiting for 3 *** previous medical and psychiatric history was *** analysis showed iron deficiency anemia,leukocytosis,and elevated liver *** abdominal CT scan revealed a dense structure in the patients’stomach which turned out to be a huge trichobezoar completely obstructing the *** trichobezoar had to be removed *** her postoperative course,a subcutaneous seroma *** a single puncture,the rest of the recovery process was unremarkable,and the patient recovered *** A mechanical bowel obstruction is a potentially life-threatening event for every *** our case a young female was suffering from severe symptoms of an obstruction which might have resulted in serious harm without successful surgical management.

关键词： Rapunzel syndrome Hair ingestion Gastroscopy Bezoar Case report

Bolstering integrity in environmental data science and machine learning requires understanding socioecological inequity

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frontiers of Environmental Science & Engineering 2024年第5期18卷 171-179页

作者： Joe f.Bozeman III School of Civil and Environmental Engineering Georgia Institute of TechnologyAtlantaGA30332USA School of Public Policy Georgia Institute of TechnologyAtlantaGA30332USA

Socioecological inequity in environmental data science—such as inequities deriving from data-driven approaches and machine learning(ML)—are current issues subject to debate and *** is growing consensus around embedding equity throughout all research and design domains—from inception to administration,while also addressing procedural,distributive,and recognitional ***,practically doing so may seem onerous or daunting to *** current perspective helps to alleviate these types of concerns by providing substantiation for the connection between environmental data science and socioecological inequity,using the Systemic Equity framework,and provides the foundation for a paradigmatic shift toward normalizing the use of equity-centered approaches in environmental data science and ML *** the integrity of environmental data science and ML is just beginning from an equity-centered tool development and rigorous application *** this end,this perspective also provides relevant future directions and challenges by overviewing some meaningful tools and strategies—such as applying the Wells-Du Bois Protocol,employing fairness metrics,and systematically addressing irreproducibility;emerging needs and proposals—such as addressing data-proxy bias and supporting convergence research;and establishes a ten-step path ***,the work that environmental scientists and engineers do ultimately affect the well-being of us all.

关键词： Equity Bias Machine Learning Data Science Justice Systemic Equity

Premature axon-oligodendrocyte interaction contributes to stalling of experimental axon regeneration after injury to the white matter

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Neural Regeneration Research 2024年第3期19卷 469-470页

作者： Ephraim f.Trakhtenberg Department of Neuroscience University of Connecticut School of MedicineFarmingtonCTUSA

Studies from nearly 3 decades ago suggested that,in the central nervous system(CNS),myelination of axons by oligodendrocytes not only helps improve axonal conductivity but also stabilizes circuitry(Colello and Schwab,1994).Over the years,myelin sheaths produced by oligodendrocytes have been found to contain multiple molecules that are inhibitory to axonal growth(e.g.,MAG,NogoA,OMgp,Semaphorins)(Yiu and He,2006;Silver et al.,2014).After white matter injury in the adult CNS,myelin debris from damaged axons and dead oligodendrocytes accumulates in the forming glial scar and exposes these myelin-associated axon growth-inhibitory molecules to the injured axonal stumps,thereby contributing to the inhibition of axonal *** development,CNS axons reach their postsynaptic targets and stop growing before oligodendrocytes appear and myelinate them(foran and Peterson,1992;Dangata et al.,1996).Therefore,myelin-associated axon growth-inhibitory molecules interacting with already grown axons during myelination were thought to block axons from promiscuous sprouting and miswiring,thereby stabilizing neural circuitry in the CNS(Colello and Schwab,1994).

关键词： thereby white injury