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Geoscience Frontiers 2016年第6期7卷 875-889页

作者： wolfgang D.Maier Bartosz T.Karykowski Sheng-Hong Yang School of Earth and Ocean Sciences Cardiff UniversityUK Oulu Mining School University of OuluFinland

The formation of anorthosites in layered intrusions has remained one of petrology＇s most enduring enigmas. We have studied a sequence of layered chromitite, pyroxenite, norite and anorthosite overlying the UG2 chromitite in the Upper Critical Zone of the eastern Bushveld Complex at the Smokey Hills platinum mine. Layers show very strong medium to large scale lateral continuity, but abundant small scale irregularities and transgressive relationships. Particularly notable are irregular masses and seams of anorthosite that have intrusive relationships to their host rocks. An anorthosite layer locally transgresses several 10 s of metres into its footwall, forming what is referred to as a ＂pothole＂ in the Bushveld Complex. It is proposed that the anorthosites formed from plagioclase-rich crystal mushes that originally accumulated at or near the top of the cumulate pile. The slurries were mobilised during tectonism induced by chamber subsidence, a model that bears some similarity to that generally proposed for oceanic mass flows. The anorthosite slurries locally collapsed into pull-apart structures and injected their host rocks. The final step was down-dip drainage of Fe-rich intercumulus liquid, leaving behind anorthosite adcumulates.

关键词： Anorthosite Layered intrusion Bushveld Complex South Africa Chromitite

Effects of newly devised plasma lice comb on human hair

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Plasma Science and Technology 2019年第12期21卷 78-84页

作者： Lars TEN BOSCH Andreas HUBER Philipp SAUERBIER Robert KOHLER Georg AVRAMIDIS wolfgang VIOL University of Applied Sciences and Arts HAWK Faculty NVon-Ossietzky-Strasse 99/10037085 GottingenGermany Neaspec GmbH Eglfinger Weg 285540 Munich-HaarGermany Wood Biology and Wood Products Faculty of Forest Sciences and Forest EcologyUniversity of GoettingenBüsgenweg 437077 GottingenGermany

A plasma device was developed showing high potential for a pesticide-free treatment of pediculosis. As a first safety assessment of the device was presented earlier, this present paper focuses on the damage introduced to human hair during a plasma treatment for pediculosis control. Therefore, human hairs were treated repeatedly to assess the possible occurring damage developing with increasing treatment durations. To analyse the inflicted changes on human hair examinations using x-ray photoelectron spectroscopy(XPS/ESCA), scanning nearfield optical microscopy(SNOM) and scanning electron microscopy were conducted, to compare the modifications of surface chemistry and mechanical alterations. The investigations revealed a mild impact on the surface chemistry(XPS/SNOM), while more distinct morphological changes on the hair surface could be observed. The authors conclude that an effect of the plasma comb device on the hair during a real-life treatment is negligible, due to the very short contact times during a standard combing procedure for pediculosis control.

关键词： atmospheric pressure plasma dielectric barrier discharge pediculosis SEM SNOM ESCA XPS hair smoothing plasma based pest management

Surface Activation of Plane and Curved Automotive Polymer Surfaces by Using a Fittable Multi-Pin DBD Plasma Source

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Plasma Science and Technology 2014年第6期16卷 593-597页

作者： Jrn HEINE Roland DAMM Christoph GERHARD Stephan WIENEKE wolfgang VIL University of Applied Sciences and Arts Laboratory of Laser and Plasma TechnologyVon-Ossietzky-Stra?e 99 37085 Gttingen Germany Fraunhofer Institute for Surface Engineering and Thin Films Application Center for Plasma and Photonic Von-Ossietzky-Stra?e 99 37085 Gttingen Germany

In this work, surface activation of automotive polymers using atmospheric pressure plasmas was investigated. The aim was to increase the polar fraction of the surface energy of both plane and convex polymer devices with a radius in the range of 30 mm. For this purpose, a fittable low temperature atmospheric pressure plasma source based on capacitively coupled multi-pin electrodes was set up and applied. Each single electrode generates a treatment spot of approximately 2 cm2 with a tunable power density of up to 1.4 W/cm2. The surface energy was evaluated by contact angle measurements. After treatment at a low energy density of 1.01 J/cm2, the polar fraction of the surface energy of the investigated polymers was increased by a factor of 3.3 to 132, depending on the polymer materials. It was shown that by applying the presented fittable plasma source, this effect is independent of the surface radius of the polymer sample.

关键词： surface activation atmospheric pressure plasma adhesion lacquering surfaceenergy

Corrosion Protection of AM50 Magnesium Alloy by Nafion/DMSO Organic Coatings

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Journal of Wuhan University of Technology(Materials Science) 2008年第2期23卷 204-206页

作者： SONG Renguo ZHENG Xiaohua BAI Shuju BLAWERT Carsten DIETZEL wolfgang The MOE Key Laboratory of Mechanical Manufacture and Automation Zhejiang University of Technology Hangzhou 310014 China Tieling Base Property Company of NEPPC Tieling 112001 China Institute of Materials Research GKSS-Forschungszentrum Geesthacht GmbH Geesthacht D-21502 Germany

The effectiveness of the corrosion protection of Nafion/Dimethysulfoxid （DMSO） organic coatings for AM50 magnesium alloy prepared by simple immersion and heat treatment was investigated. Its corrosion resistance and morphologies of the Nafion/DMSO organic coatings were studied by electrochemical corrosion testing and optical microscopy. The results show that Nafion/DMSO organic coatings can improve the corrosion resistance of AM50 magnesium alloy effectively. Also, the corrosion resistance increases with the surface density of the organic coatings.

关键词： corrosion protection magnesium alloy organic coatings

Electrochemical drag effect on grain boundary motion in ionic ceramics

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npj Computational Materials 2020年第1期6卷 305-311页

作者： K.S.N.Vikrant wolfgang Rheinheimer R.Edwin García School of Materials Engineering Purdue UniversityWest LafayetteIN 47907USA

The effects of drag imposed by extrinsic ionic species and point defects on the grain boundary motion of ionic polycrystalline ceramics were quantified for the generality of electrical,chemical,or structural driving *** the absence of,or for small driving forces,the extended electrochemical grain boundary remains pinned and symmetrically distributed about the structural *** the grain boundary begins to move,charged defects accumulate unsymmetrically about the structural grain boundary *** the critical driving force for motion,grain boundaries progressively shed individual ionic species,from heavier to lighter,until they display no interfacial electrostatic charge and zero Schottky *** p-n junction moving grain boundaries that induce a finite electrostatic potential difference across entire grains are identified for high velocity *** developed theory is demonstrated for Fe-doped SrTiO_(3).The increase in average Fe concentration and grain boundary crystallographic misorientation enhances grain boundary core segregation and results in thick space charge layers,which leads to a stronger drag force that reduces the velocity of the *** developed theory sets the stage to assess the effects of externally applied fields such as temperature,electromagnetic fields,and chemical stimuli to control the grain growth for developing textured,oriented microstructures desirable for a wide range of applications.

关键词： grain boundary ceramics

Diagnostic criteria for acute liver failure due to Wilson disease

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World Journal of Gastroenterology 2007年第11期13卷 1711-1714页

作者： Christoph Eisenbach Olivia Sieg wolfgang Stremmel Jens Encke Uta Merle University Hospital of Heidelberg Department of Gastroenterology and Hepatology Im Neuenheimer Feld 410 Heidelberg D-69120 Germany

AIM： To describe the diagnostic criteria for acute liver failure due to Wilson disease （WD）, which is an uncommon cause of acute liver failure （ALF）. METHODS： We compared findings of patients presenting with ALF due to WD to those with ALF of other etiologies. RESULTS： Previously described criteria, such as low alkaline phosphatase activity, ratio of low alkaline phosphatase to total bilirubin or ratio of high aspartate arninotransferase （AST） to alanine arninotransferase （ALT）, failed to identify patients with ALF due to WD. There were significant differences in low ALT and AST activities （53 ± 43 vs 1982 ± 938, P 〈 0.0001 and 87 ± 44 vs 2756 ± 2941, P = 0.037, respectively）, low choline esterase activity （1.79 ± 1.2 vs 4.30 ± 1.2, P = 0.009）, high urine copper concentrations （93.4 ± 144.0 vs 3.5 ± 1.8, P = 0.001） and low hemoglobin （7.0 ± 2.2 vs 12.6 ± 1.8, P 〈 0.0001） in patients with ALF caused by WD as compared with other etiologies. Interestingly, 4 of 7 patients with ALF due to WD survived without liver transplantation. CONCLUSION： In ALF, these criteria can help establish a diagnosis of WD. Where applicable, slitlamp examination for presence of Kayser-Fleischer rings and liver biopsy for determination of hepatic copper concentration still remain important for the diagnosis of ALF due to WD. The need for liver transplantation should be evaluated carefully as the prognosis is not necessarily fatal.

关键词： Acute liver failure Copper metabolism Fulminant hepatic failure Wilson disease Liver transplantation

Are heat stroke and physical exhaustion underestimated causes of acute hepatic failure?

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World Journal of Gastroenterology 2007年第2期13卷 306-309页

作者： Kilian Weigand Carina Riediger wolfgang Stremmel Christa Flechtenmacher Jens Encke Department of Gastroenterology and Hepatology Medicine Ⅳ University of Heidelberg 69120 Heidelberg Germany Department of Pathology University of Heidelberg 69120 Heidelberg Germany

While cardiopulmonary symptoms are common in patients undergoing dassical or, due to physical exercise, exertional heat stroke, the failure of other organs is a rarely described phenomenon. Here we present two cases of acute hepatic failure, one due to classic heat shock, while the other occurred while the patient was doing a marathon-type running. Both cases presented with very high transaminases and significantly elevated international normalized ratio （INR）. No other causes for liver failure could be identified but physical exhaustion and hyperthermia.

关键词： Heat stroke Acute hepatic failure Heat shock Liver failure Hyperthermia

In-silico synthesis of lowest-pressure high-T_(c) ternary superhydrides

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npj Computational Materials 2022年第1期8卷 1119-1125页

作者： Roman Lucrezi Simone Di Cataldo wolfgang von der Linden Lilia Boeri Christoph Heil Institute of Theoretical and Computational Physics Graz University of TechnologyNAWI Graz8010GrazAustria Dipartimento di Fisica Sapienza Universitàdi Roma00185RomeItaly Enrico Fermi Research Center Via Panisperna 89 A00184RomeItaly

We report the theoretical prediction of two high-performing hydride superconductors BaSiH_(8)and SrSiH_(8).They are thermodynamically stable above pressures of 130 and 174 GPa,respectively,and metastable below *** anharmonic phonon calculations,we determine the minimum pressures of dynamical stability to be around 3 GPa for BaSiH8 and 27 GPa for SrSiH_(8),and using the fully anisotropic Migdal-Eliashberg theory,we predict Tc’s around 71 and 126 K,*** also introduce a method to estimate the lowest pressure of synthesis,based on the calculation of the enthalpy barriers protecting the BaSiH_(8)Fm3¯m structure from decomposition at various *** kinetic pressure threshold is sensibly higher than the one based on dynamic stability,but gives a much more rigorous limit for synthesizability.

关键词： synthesis stability high

Exogenous nitrogen input skews estimates of microbial nitrogen use efficiency by ecoenzymatic stoichiometry

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Ecological Processes 2023年第1期12卷 625-631页

作者： Lifei Sun Daryl L.Moorhead Yongxing Cui wolfgang Wanek Shuailin Li Chao Wang CAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Department of Environmental Sciences University of ToledoToledo 43606USA Sino-French Institute for Earth System Science College of Urban and Environmental SciencesPeking UniversityBeijing 100871China Division of Terrestrial Ecosystem Research Center of Microbiology and Environmental Systems ScienceUniversity of ViennaDjerassiplatz 11030 ViennaAustria

Background Ecoenzymatic stoichiometry models(EEST)are often used to evaluate microbial nutrient use efficiency,but the validity of these models under exogenous nitrogen(N)input has never been ***,we investigated the effects of long-term N addition(as urea)on microbial N use efficiency(NUE),compared EEST and^(18)O-labeling methods for determining NUE,and evaluated EEST’s theoretical assumption that the ratios of standard ecoenzymatic activities balance resource availability with microbial *** We found that NUE estimated by EEST ranged from 0.94 to *** contrast,estimates of NUE by the^(18)O-labeling method ranged from 0.07 to *** large differences in NUE values estimated by the two methods may be because the sum ofβ-N-acetylglucosaminidase and leucine aminopeptidase activities in the EEST model was not limited to microbial N acquisition under exogenous N inputs,resulting in an overestimation of microbial NUE by *** addition,the acquisition of carbon by N-acquiring enzymes also likely interferes with the evaluation of NUE by *** Our results demonstrate that caution must be exercised when using EEST to evaluate NUE under exogenous N inputs that may skew standard enzyme assays.

关键词： Extracellular enzyme Resource allocation Nitrogen addition Microbial metabolism limitation Isotope labeling

Current collectors based on multiwalled carbon-nanotubes and fewlayer graphene for enhancing the conversion process in scalable lithium-sulfur battery

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Nano Research 2023年第6期16卷 8433-8447页

作者： Vittorio Marangon Edoardo Barcaro Luca Minnetti wolfgang Brehm Francesco Bonaccorso Vittorio Pellegrini Jusef Hassoun Graphene Labs Istituto Italiano di TecnologiaGenoa 16163Italy Department of Chemical Pharmaceutical and Agricultural SciencesUniversity of FerraraFerrara 44121Italy BeDimensional S.p.A. Genoa 16163Italy National Interuniversity Consortium of Materials Science and Technology(INSTM) University of Ferrara Research UnitFerrara 44121Italy

We investigated herein the morphological,structural,and electrochemical features of electrodes using a sulfur(S)-super P carbon(SPC)composite(i.e.,S@SPC-73),and including few-layer graphene(FLG),multiwalled carbon nanotubes(MWCNTs),or a mixture of them within the current collector ***,we studied the effect of two different electron-conducting agents,that is,SPC and FLG,used in the slurry for the electrode *** supports have high structural crystallinity,while their morphologies are dependent on the type of material *** voltammetry(CV)shows a reversible and stable conversion reaction between Li and S with an activation process upon the first cycle leading to the decrease of cell *** activation process is verified by electrochemical impedance spectroscopy(EIS)with a decrease of the resistance after the first CV ***,CV at increasing scan rates indicates a Li+diffusion coefficient(D)ranging between 10^(−9) and 10^(−7) cm^(2)·s^(−1)in the various states of charge of the cell,and the highest D value for the electrodes using FLG as electron-conducting *** tests performed at constant current of C/5(1 C=1675 mA·g_(s)^(−1))show high initial specific capacity values,which decrease during the initial cycles due to a partial loss of the active material,and subsequently increase due to the activation *** the electrodes show a Coulombic efficiency higher than 97%upon the initial cycles,and a retention strongly dependent on the electrode ***,this study suggests a careful control of the electrode in terms of current collector design and slurry composition to achieve good electrode morphology,mechanical stability,and promising electrochemical performance in practical Li-S cells.

关键词： lithium-sulfur battery current collector few-layer graphene carbon nanotubes scalability sulfur loading