Martin Luther University of Halle-Wittenberg

About: Martin Luther University of Halle-Wittenberg is a education organization based out in Halle, Germany. It is known for research contribution in the topics: Population & Liquid crystal. The organization has 20232 authors who have published 38773 publications receiving 965004 citations. The organization is also known as: MLU & University of Wittenberg.

Chernozem-soil of the year 2005.

Abstract: The proclamation of the “Soil of the Year” was made for the first time in Germany in 2005 on occasion of the World Soil Day. Chernozems were selected for this purpose. In this paper an overview of these groups of soils is given. Chernozems are concentrated in the drought region of Central Germany. A standard profile from the core area of Chernozems developed from loess is presented with comprehensive laboratory analysis. Chernozems developed primarily upon carbonatic loess substrates under summer-dry climatic conditions in an open park-like landscape with isolated forest stands. The development of Chernozems began as early as the late glacial period, and they were fully developed by the Atlantikum age. The far-reaching, uniformly thick humus horizons indicate substrate differences in the loess cover, which are partly the result of bioturbation. Within Germany, Chernozems and Chernozem-like soils make up approx. 3% of the surface area and 5% (approx. 11,000 km2) of the arable land. The results of the Static Fertilization Experiment in Bad Lauchstadt, founded in 1902, clarify the high value of Chernozem for biomass production and the environment. Each loss due to erosion or decrease in surface area reduces the fulfillment of soil ecological functions of the soils and is comparable to a loss of animal and plant species. Therefore, soil scientists and the results of soil research must be more comprehensively implemented for soil preservation, protection, and politics. For acceptance of these goals among the general public and the political-decision makers, the campaign “Soil of the Year” should give some thought-provoking impulses. Schwarzerde – Boden des Jahres 2005 Anlasslich des Weltbodentages wurde in Deutschland fur 2005 mit der Schwarzerde erstmalig ein „Boden des Jahres” proklamiert. Damit soll in der Bevolkerung und bei politischen Entscheidungstragern ein starkeres Bewusstsein fur den Boden und ein hoheres Engagement fur den Bodenschutz angeregt werden. Im Beitrag wird ein Uberblick uber diese Bodengruppe gegeben und ein Standardprofil aus dem Kerngebiet der Schwarzerden aus Loss (Mitteldeutsches Trockengebiet) mit umfassenden Laboranalysen exemplarisch prasentiert. Schwarzerden entwickelten sich vorwiegend auf kalkreichen Lossen unter sommertrockenen Klimabedingungen in einer offenen parkahnlichen Landschaft mit Waldinseln. Die Entstehung der Schwarzerden setzte bereits im Spatglazial ein, und im Atlantikum waren sie voll entwickelt. Die weitraumig gleiche Machtigkeit der Humushorizonte zeichnet primare Substratunterschiede in der Lossdecke nach; sie sind nicht nur das Ergebnis einer Bioturbation. In Deutschland nehmen die Schwarzerden und schwarzerdeahnlichen Boden etwa 3 % der Bodenflache bzw. 5 % (ca. 11.000 km2) der landwirtschaftlichen Nutzflache ein. Die Ergebnisse des seit 1902 bestehenden Statischen Dungungsversuchs Bad Lauchstadt verdeutlichen den hohen Wert der Schwarzerden fur Biomasseproduktion und Umwelt. Jeder Verlust durch Erosion oder Flachenentzug mindert die Erfullung okologischer Funktionen der Boden und ist dem Artenverlust von Tieren und Pflanzen gleichzustellen. In der Bodenpolitik mussen deshalb die Ergebnisse der Bodenforschung zum Erhalt und Schutz unserer Boden umfassender als bisher umgesetzt und Bodenwissenschaftler starker in politische Entscheidungen eingebunden werden. Fur die Akzeptanz und Umsetzung dieser Ziele in der Offentlichkeit soll der „Boden des Jahres” Impulse geben.

The effect of specific β‐nucleation on morphology and mechanical behavior of isotactic polypropylene

Abstract: The commercial grade of isotactic polypropylene was modified by a specific β-nucleating agent in a broad concentration range. The supermolecular structure of the specimens prepared by injection molding was characterized by X-ray scattering and correlated with mechanical behavior. It was found that at a critical nucleant concentration of 0.03 wt % the content of the β-modification virtually reaches a saturation level. With further addition of the nucleant, the β-phase content increases only slightly. The long period passes through a distinct maximum at the same nucleant concentration. This singularity in structure remarkably correlates with a minimum of the yield stress and maxima of strain at break and fracture toughness. Such general behavior is also reflected in the correlation between the β-phase concentration and fracture toughness profiles along the injection-molded bars. It is suggested that in the critically nucleated material an optimum thickness of the amorphous interlayer with connecting chains between the β-crystallites is established, rendering the material the highest possible ductility and toughness. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1174–1184, 2002

Beyond skyrmions: Review and perspectives of alternative magnetic quasiparticles

Abstract: Magnetic skyrmions have attracted enormous research interest since their discovery a decade ago. The non-trivial real-space topology of these nano-whirls leads to fundamentally interesting and technologically relevant consequences - the skyrmion Hall effect of the texture and the topological Hall effect of the electrons. Furthermore, it grants skyrmions in a ferromagnetic surrounding great stability even at small sizes, making skyrmions aspirants to become the carriers of information in the future. Still, the utilization of skyrmions in spintronic devices has not been achieved yet, among other reasons, due to shortcomings in their current-driven motion. In this review, we present recent trends in the field of topological spin textures that go beyond skyrmions. The majority of these objects can be considered a combination of multiple subparticles, such as the bimeron, or the skyrmion analogues in different magnetic surroundings, such as antiferromagnetic skyrmions, as well as three-dimensional generalizations, such as hopfions. We classify the alternative magnetic quasiparticles - some of them observed experimentally, others theoretical predictions - and present the most relevant and auspicious advantages of this emerging field.

Corundum Structure Oxides Studied by XPS

Abstract: The electronic structure behaviour of Me2O3 oxides (Me = Ti, V, Cr) has been determined from XPS valence band and core level measurements. From Ti to Cr sesquioxide the relative intensity of the 3d band increases systematically which can be explained by the (atomic) photoelectric cross section and the number of 3d electrons. Simultaneously the 3d-2p band separation decreases indicating a more stronger band overlap equivalent an enhanced covalent bonding component. The different electrical properties among the corundum structure oxides are determined by the trigonal field splitted a1g and eg orbitals, their occupation and relative energy position at the Fermi level. The observations confirm the change from itinerant to more localized behaviour of d electrons caused by crystal structure parameter change (c/a ratio).