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Electron–plasmon and electron–magnon scattering in ferromagnets from first principles by combining GW and GT self-energies

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npj Computational Materials 2021年第1期7卷 1619-1632页

作者： Dmitrii Nabok Stefan blügel Christoph Friedrich Peter Grünberg Institut and Institut for Advanced Simulation Forschungszentrum JülichJülich 52425Germany

This work combines two powerful self-energy techniques:the well-known GW method and a self-energy recently developed by us that describes renormalization effects caused by the scattering of electrons with magnons and Stoner *** GT selfenergy,which is fully k-dependent and contains infinitely many spin-flip ladder diagrams,was shown to have a profound impact on the electronic band structure of Fe,Co,and *** the present work,we refine the method by combining GT with the GW *** resulting GWT spectral functions exhibit strong lifetime effects and emergent dispersion *** are in an overall better agreement with experimental spectra than those obtained with GW or GT alone,even showing partial improvements over local-spin-density approximation dynamical mean-field *** performed analysis provides a basis for applying the GWT technique to a wider class of magnetic materials.

关键词： materials theory infinitely

Mobile NMR for geophysical analysis and materials testing

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Petroleum Science 2009年第1期6卷 1-7页

作者： blüMICH Bernhard MAULER jrg HABER Agnes PERLO juan DANIELI Ernesto CASANOVA Federico Institut für Technische und Makromolekulare Chemie RWTH Aachen University

Initiated by well logging NMR, portable NMR instruments are being developed for a variety of novel applications in materials testing, process analysis and control, which provides new opportunities for geophysical investigations. Small-diameter cylindrical sensors can probe short distances into the walls of slim-line logging holes, and single-sided sensors enable non-destructive testing of large objects. Both sensors are characterized by small sensitive volumes. Barrel-shaped magnets that accommodate the sample in their center have higher sensitivity due to a larger sensitive volume but can accommodate only samples like drill cores, which fit in size to the diameter of the magnet bore. Both types of magnets can be scaled down to the size of a coffee mug to arrive at sub-compact NMR equipment. Portable NMR magnets are reviewed in the context of applications related to geophysics.

关键词： Mobile NMR portable NMR relaxation imaging spectroscopy

The AiiDA-KKR plugin and its application to highthroughput impurity embedding into a topological insulator

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npj Computational Materials 2021年第1期7卷 108-116页

作者： Philipp Rüßmann Fabian Bertoldoand Stefan blügel Peter Grünberg Institut and Institute for Advanced Simulation Forschungszentrum Jülich and JARAD-52425 JülichGermany

The ever increasing availability of supercomputing resources led computer-based materials science into a new era of highthroughput ***,Pizzi et *** the AiiDA framework that provides a way to automate calculations while allowing to store the full provenance of complex workflows in a *** present the development of the AiiDA-KKR plugin that allows to perform a large number of ab initio impurity embedding calculations based on the relativistic full-potential Korringa-Kohn-Rostoker Green function *** capabilities of the AiiDA-KKR plugin are demonstrated with the calculation of several thousand impurities embedded into the prototypical topological insulator *** results are collected in the juDiT database which we use to investigate chemical trends as well as Fermi level and layer dependence of physical properties of *** includes the study of spin moments,the impurity’s tendency to form in-gap states or its effect on the charge doping of the *** properties depend on the detailed electronic structure of the impurity embedded into the host crystal which highlights the need for ab initio calculations in order to get accurate predictions.

关键词： method topological embedding

Effects of external temperature and dead volume on laboratory measurements of pore pressure and injected volume in a rock fracture

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journal of Rock Mechanics and Geotechnical Engineering 2022年第5期14卷 1461-1469页

作者： Yinlin ji Christian Kluge Hannes Hofmann Guido blöcher Helmholtz Centre Potsdam GFZ German Research Centre for GeosciencesPotsdam14473Germany State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou221116China

The accurate evaluation of pore pressure and injected volume is crucial for the laboratory characterization of hydromechanical responses of rock fractures. This study reports a series of laboratory experiments to systematically demonstrate the effects of external temperature and dead volume on laboratory measurements of pore pressure and injected volume in a rock fracture. We characterize the hydraulic aperture of the fracture as a function of effective normal stress using the exponential aperture *** model is then employed to predict the pore pressure change and injected volume in the fracture without the influences of external temperature and dead volume. The external temperature changes in the cyclic loading test due to the joule-Thompson effect for fluids. The effect of external temperature on pore pressure change in the fracture can be well explained by thermal pressurization of fluids. Our results also show that the external dead volume can significantly lower the pore pressure change in the fracture during the cyclic loading test under undrained conditions. The injected volume can also be substantially enlarged due to the external dead volume in a typical pore pressure system. Internal measurement of the pore pressure in the fracture using a fiber optic sensor cannot exclude the influences of external temperature and dead volume, primarily because of the good hydraulic communication between the fracture and pore pressure system. This study suggests that the effects of external temperature and dead volume on pore pressure response and injected volume should be evaluated for accurate laboratory characterization and inter-laboratory comparison.

关键词： Fracture aperture Thermal pressurization External dead volume Pressure attenuation Injected volume Fiber optic sensor

Tree diversity and nectar composition affect arthropod visitors on extrafloral nectaries in a diversity experiment

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journal of Plant Ecology 2017年第1期10卷 201-212页

作者： Michael Staab joel Methorst jan Peters Nico blüthgen Alexandra-Maria Klein Faculty of Environment and Natural Resources Chair of Nature Conservation and Landscape EcologyUniversity of FreiburgTennenbacher Straße 479106 FreiburgGermany Institute of Ecology Leuphana University of LüneburgScharnhorststraße 121335 LüneburgGermany Ecological Network Group Department of BiologyTechnical University DarmstadtSchnittspahnstraße 1064287 DarmstadtGermany

Aims Plants with extrafloral nectaries(EFNs)are common in tropical and subtropical habitats and,despite many other arthropods also forage for EFN,most studies solely focused on the defense mutualisms between EFN plants and *** study aims at a quantitative assessment of the entire arthropod community that visits EFN trees to compare visitor communities between different tree species to disentangle the mechanisms that may drive EFN visitor community *** also test for tree diversity effects on EFN visitors,as it is unknown if local tree species richness relates to the abundance and species richness of arthropods foraging for *** We sampled EFN-visiting arthropods in the experimental tree species richness gradient of the BEF-China Experiment,the currently largest forest diversity experiment in the world,and tested if tree species richness affects EFN visitors and if visitor community composition differs between EFN tree *** a second step,we analyzed the EFN of Ailanthus altissima and Triadica cochinchinensis,the two EFN tree species with highest visitor abundance,for sugars and amino acids(AA)to test if tree species-specific differences in nectar chemistry translate to differing visitor ***,we conducted a choice experiment using different artificial nectar solutions to test if nectar quality affects foraging decisions of ants,the most frequent EFN visitors in our study *** Findings EFN trees in young successional forests in subtropical South-East China are visited by a diverse assemblage of arthropods including ants,beetles,flies,and *** ants accounted for about 75%of all individuals,non-ant visitors were by far more species *** abundance and species richness declined with increasing tree species richness,suggesting a resource dilution effect,because plots with more tree species had proportionally less EFN tree individuals and thus lower nectar *** altissima and ***

关键词： amino acids BEF-China choice experiment formicidae HPLC chemical analysis

Bioelectrochemically-assisted degradation of chloroform by a coculture of Dehalobacter and Dehalobacterium

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Environmental Science and Ecotechnology 2022年第4期12卷 81-86页

作者： David Fernandez-Verdejo Pilar Cortés Albert Guisasola Paqui blánquez Ernest Marco-Urrea Biorem UAB Department of ChemicalBiological and Environmental EngineeringSchool of EngineeringUniversitat Autonoma de Barcelona08193BellaterraBarcelonaSpain Departament de Genetica i de Microbiologia Facultat de BioCienciesUniversitat Autonoma de Barcelona08193BellaterraBarcelonaSpain GENOCOV Department of ChemicalBiological and Environmental EngineeringSchool of EngineeringUniversitat Autonoma de Barcelona08193BellaterraBarcelonaSpain

Using bioelectrochemical systems(BESs)to provide electrochemically generated hydrogen is a promising technology to provide electron donors for reductive dechlorination by organohalide-respiring *** this study,we inoculated two syntrophic dechlorinating cultures containing Dehalobacter and Dehalobacterium to sequentially transform chloroform(CF)to acetate in a BES using a graphite fiber brush as the *** this co-culture,Dehalobacter transformed CF to stoichiometric amounts of dichloromethane(DCM)via organohalide respiration,whereas the Dehalobacterium-containing culture converted DCM to acetate via *** were initially inoculated with Dehalobacter,and sequential cathodic potentials of-0.6,-0.7,and -0.8 V were poised after consuming three CF doses(500 μM)per each potential during a time-span of 83 *** the end of this period,the accumulated DCM was degraded in the following seven days after the inoculation of *** this point,four consecutive amendments of CF at increasing concentrations of 200,400,600,and 800 μM were sequentially transformed by the combined degradation activity of Dehalobacter and *** Dehalobacter 16S rRNA gene copies increased four orders of magnitude during the whole *** coulombic efficiencies associated with the degradation of CF reached values>60% at a cathodic potential of -0.8 V when the degradation rate of CF achieved the highest *** study shows the advantages of combining syntrophic bacteria to fully detoxify chlorinated compounds in BESs and further expands the use of this technology for treating water bodies impacted with pollutants.

关键词： Dehalobacter Dehalobacterium Chloroform Dichloromethane Bioelectrochemistry Bioremediation

TCP14 and TCP15 Mediate the Promotion of Seed Germination by Gibberellins in Arabidopsis thaliana

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Molecular Plant 2015年第3期8卷 482-485页

作者： Francesca Resentini Amelia Felipo-Benavent Lucia Colombo Miguel A. blázquez David Alabadí Simona Masiero Dipartimento di Bioscienze Università. degli Studi di Milano via Celoria 26 20133 Milano Italy Instituto de Biologfa Molecular y Celular de Plantas (CSIC-Universidacl Politécnica de Valencia) Ingeniero Fausto Elio sin 46022 Valencia Spain

Dear Editor,Seed germination is a major developmental transition in a plant＇s life that involves the concerted action of several genetic and physiological pathways （Holdsworth et al., 2008）, and mostly consists of the resumption of embryo growth after a long quiescence imposed during seed maturation. In mature seeds, germination is repressed by abscisic acid （ABA）, while favorable environmental conditions promote gibberellin （GA） biosynthesis and decrease ABA （Holdsworth et al., 2008）. The increase in GA levels is essential for the rupture of testa and endosperm （Lee et al., 2002）. The activation of cell division in the embryo is an integral part of germination that precedes the protrusion of the root through the seed coat. In Arabidopsis, this activation has been linked to significant early changes in the expression of cell-cycle elements （Masubelele et al., 2005）. In the root apical meristem （RAM）, GAs regulate cell divisions （Achard et al., 2009; 0beda-Tomás et al., 2009）. Similarly, the transcription factors （TFs） TEOSINTE BRANCHED1/ CYCLOIDEA/PROLIFERATING CELL FACTOR14 （TCP14） and TCP15 have been proposed to regulate cell proliferation （Kieffer et al., 2011）. Moreover, the activity of TCP14 is necessary to undergo seed germination and, remarkably, seeds lacking this activity are hypersensitive to the negative effects on germination of GA biosynthesis inhibitor paclobutrazol, suggesting a functional relationship between this TF and GAs （Tatematsu et al., 2008）. Taking these observations into account, we hypothesized that TCP14 and TCP15 mediate GA-dependent activation of the cell cycle during germination.

关键词： @@

Permanent Grasslands in an Anthropogenically Burdened Region,and Their Contribution to Sustainable Development

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Agricultural Sciences 2017年第8期8卷 816-824页

作者： jaroslava Vráblíková Petr Vráblík Eliska Wildova Miloslav Soch Department of Natural Sciences Faculty of EnvironmentJ.E.Purkyne University in Usti nad LabemUsti nad LabemCzech Republic Faculty of Agriculture University of South Bohemia in Ceske BudejoviceCeske BudejoviceCzech Republic

The landscape of the northern part of the Czech Republic (the Chomutov, Most, Teplice and ústí nad Labem districts) has long been burdened by the surface mining of brown coal. Within the reclamation and restoration processes, the anthropogenic formations which were created have been successfully integrated into the surrounding landscape. One of the important regional elements which have been utilized during the regeneration is permanent grasslands (PGL). They are of considerable importance not only for cattle grazing, but also for the preservation of the region’s biodiversity and protection of the soil. The contribution deals with the production and non-production functions of permanent grasslands in the landscape, and their significance within the scope of the permanently sustainable development of an anthropogenically burdened region. Permanent grasslands are part of the agricultural landscape, but their significance is multifunctional, because they not only provide an environment for cattle grazing, but also protect soil, the nutrient cycle and the microclimate, and preserve biodiversity. At the same time, the article analyzes in detail the development of this vegetation in the area of interest-Northern Bohemia. During the period of the greatest mining boom (1967-1990), its rapid decrease-by as much as 4500 ha-was recorded in some areas. Since the year 1990, there has been a significant growth in the most damaged areas. At present, the development of PGLs has stabilized.

关键词： Soil land Use Agricultural Land Permanent Grasslands Sustainable Development Northern Bohemia

Evaluation of the Forest Reclamation of the Anthroposoil Dump at the Bilina Mines Created from Marlstone

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Open journal of Soil Science 2018年第12期8卷 360-367页

作者： Petr Vráblík Michal Rehor Pavel Schmidt jaroslava Vráblíková Department of Natural Sciences Faculty of EnvironmentJ.E.Purkyne University in Usti nad LabemUsti nad LabemCzech Republic Research Institute for Brown Coal in Most MostCzech Republic

When reclaiming the surface of the Radovesická dump in the North Bohemian brown coal basin, the most commonly used marls and marlstones are extracted in the foreland of filled-in territory. The most frequent reclamations are the formation of overgrown and humus anthroposoil. The soil properties of the anthroposoils for forestry purposes and the growth vitality of a broader assortment of woody plants in the age of 12 - 14 years are evaluated. It has been found that the very good growth vitality on these anthroposoils is shown by most of the trees of domestic origin (Populus nigra L., Acer pseudoplatanus L., Pinus sylvestris L., Alnus glutinosa (L.) Gaertn., Fraxinus excelsior L., Betula verrucosa Ehrh., Quercus robur L., Tilia cordata Mill.), including some of the tree species introduced (Larix decidua L., Pinus nigra Arn.) and reclamations of atypical atrophic soil horizons did not negatively affect their development.

关键词： Anthroposoil Landfill Forest Reclamation Marlstone Loamy Clay Soil Properties Growth Vitality