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21.
Magnetic susceptibility measurements are widely used to map and monitor the heavy metal pollution of soils. However, the magnetic properties of soils are influenced significantly by the bedrock lithology and soil-forming processes. Therefore, a main challenge in the data interpretation is to filter out the anthropogenic pollution signal. In this study we address this problem by analysing susceptibility values, heavy metal concentrations, as well as pedological parameters in a large soil data set from the eastern segment of Austria, covering a wide range of different lithologies and soil types. The statistic assessment demonstrates an influence of lithology and soil type on the magnetic susceptibility signal. Therefore anomalies are defined in sub sets of different soil types separately. Three different methods were applied to detect susceptibility anomalies: the median absolute deviation method, the boxplot method, and the population modelling method. These methods evaluate topsoil data only and can therefore also be applied to field measurements of magnetic susceptibility. The results were compared to the conventional method of calculating the difference of topsoil and subsoil susceptibility. All three approaches identify the main anomalies in the study area and are successful in circumventing the problem of erroneous anomaly definition due to pedological processes. However, knowledge of the lithological background is still necessary for a meaningful interpretation and can only be substituted by a large amount of data. The tested methods lead to thresholds of different height and therefore act as filters of different strength for the definition of anomalies.  相似文献   
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This paper presents an extension to the existing dynamic relaxation method to include equality constraint conditions in the process. The existing dynamic relaxation method is presented as a general, gradient‐based, minimization technique. This representation allows for the introduction of the projected gradient, discrete parallel transportation and pull back operators that enable the formulation of the geodesic dynamic relaxation method, a method that accounts for equality constraint conditions. The characteristics of both the existing and geodesic dynamic relaxation methods are discussed in terms of the system's conservation of energy, damping (viscous, kinetic, and drift), and geometry generation. Particular attention is drawn to the introduction of a novel damping approach named drift damping. This technique is essentially a combination of viscous and kinetic damping. It allows for a smooth and fast convergence rate in both the existing and geodesic dynamic relaxation processes. The case study was performed on the form‐finding of an iconic, ridge‐and‐valley, pre‐stressed membrane system, which is supported by masts. The study shows the potential of the proposed method to account for specified (total) length requirements. The geodesic dynamic relaxation technique is widely applicable to the form‐finding of force‐modeled systems (including mechanically and pressurized pre‐stressed membranes) where equality constraint control is desired. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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A micro/nano‐fabrication process of a nanochannel electroporation (NEP) array and its application for precise delivery of plasmid for non‐viral gene transfection is described. A dip‐combing device is optimized to produce DNA nanowires across a microridge array patterned on the polydimethylsiloxane (PDMS) surface with a yield up to 95%. Molecular imprinting based on a low viscosity resin, 1,4‐butanediol diacrylate (1,4‐BDDA), adopted to convert the microridge‐nanowire‐microridge array into a microchannel‐nanochannel‐microchannel (MNM) array. Secondary machining by femtosecond laser ablation is applied to shorten one side of microchannels from 3000 to 50 μm to facilitate cell loading and unloading. The biochip is then sealed in a packaging case with reservoirs and microfluidic channels to enable cell and plasmid loading, and to protect the biochip from leakage and contamination. The package case can be opened for cell unloading after NEP to allow for the follow‐up cell culture and analysis. These NEP cases can be placed in a spinning disc and up to ten discs can be piled together for spinning. The resulting centrifugal force can simultaneously manipulate hundreds or thousands of cells into microchannels of NEP arrays within 3 minutes. To demonstrate its application, a 13 kbp OSKM plasmid of induced pluripotent stem cell (iPSC) is injected into mouse embryonic fibroblasts cells (MEFCs). Fluorescence detection of transfected cells within the NEP biochips shows that the delivered dosage is high and much more uniform compared with similar gene transfection carried out by the conventional bulk electroporation (BEP) method.  相似文献   
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The reinforcement of a specifically developed fine grained cement matrix with glass fibre textiles in high fibre volume fractions creates a fire safe composite that has-besides its usual compressive strength-an important tensile capacity and omits the need for any steel reinforcement. Strongly curved shells made of textile reinforced cement composites (TRC) can cover medium (up to 15 m) span spaces with three times smaller shell thicknesses than conventional steel-reinforced concrete shells. This paper presents a methodology to generate force-modelled anticlastic shell shapes that exploit both the tensile and compressive load carrying capacities of TRC. The force-modelling is based on the dynamic relaxation form finding method developed for gravity (in this case self-weight) loaded systems. The potential of the presented methodology to develop structurally sound anticlastic shell shapes is illustrated by four case studies.  相似文献   
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Zusammenfassung Die Angaben über den Fischotter(Lutra lutra), die in den deutschen und österreichischen Jagdstatistiken aus der Zeit von 1830 bis 1936 enthalten sind, werden ausgewertet. Ziel ist es, anhand der Fang-und Abschußziffern Grundlagen für die Schätzung der Populationsentwicklung und der Populationsdichte zu erarbeiten. Der Betrachtung liegt ein Territorium von ca. 641 000 km2 — das Deutsche Reich vor 1914 und Österreich in seinen heutigen Grenzen — zugrunde. Eine etwa sechs Jahrzehnte umfassende dynamische Betrachtung der ausgewiesenen Wildertragszahlen läßt einen von wirtschaftlichen Überlegungen bestimmten verstärkten Eingriff in den Fischotterbestand während der letzten zwei Jahrzehnte des 19. Jahrhunderts erkennen, doch weichen die Fang- und Abschußziffern vor und nach dieser als Ottersturm bezeichneten Periode nicht wesentlich voneinander ab. Lokale Populationen mögen hierdurch bereits stark dezimiert worden sein. Eine Gefährdung der Art bestand jedoch noch nicht. Der rapide Rückgang bis zum völligen Zusammenbruch der Fischotterpopulation vollzog sich erst vom zweiten bis vierten Jahrzehnt unseres Jahrhunderts und ist vornehmlich auf veränderte Umweltbedingungen zurückzuführen. Die Zahlen für das der Untersuchung zugrunde liegende Territorium lassen außerdem eine abnehmende Populationsdichte von Norden und Westen nach Süden und Osten erkennen. In Pommern, Schleswig-Holstein, Hessen-Nassau und Brandenburg lebten auf je 10 000 ha erheblich mehr Fischotter als in Süd- und Ostdeutschland oder gar in Österreich. Eine konsequente Deutung der statistischen Zahlen erlaubt die Ermittlung der Kreise (in Deutschland) bzw. der Bezirkshauptmannschaften in Österreich als kleinsten territorialen Einheiten mit dem an der Jagdfläche gemessenen höchsten Fischotterertrag. In den achtziger und neunziger Jahren des vorigen Jahrhunderts wurden im Deutschen Reich und den deutsch sprechenden Teilen Österreichs etwa 6000 bis 6500, in den vorhergehenden Jahrzehnten des vorigen und im ersten Jahrzehnt unseres Jahrhunderts etwa 3500 bis 4500 Fischotter erlegt.
The otter (Lutra lutra) as seen in German and Austrian hunting statistics between 1830 and 1936
Summary The data on the otter(Lutra lutra) which appear in the German and Austrian hunting statistics for the period 1830 to 1936 are analysed. The aim is to work out bases for the estimation of population development and density with the aid of the figures for capture and shooting. The study is based on a territory of around 641 000 km2 — the German Reich prior to 1914 and Austria within its present borders. A dynamic study, covering almost six decades, of the game statistics shows an increased attack on the otter population for commercial reasons during the last two decades of the 19th century. The capture and shooting figures before and after this period of otter attack do not, however, differ from one another to any great extent. Many local populations may well have been decimated as a result. However, the species was not endangered by it. The rapid decline, leading to the complete collapse of the otter population, took place only from the 2nd to the 4th decades of the 20th century and is attributable to changed environmental conditions. Figures for the study area also show a decreasing population density from the north and west to the south and east. In Pomerania, Schleswig-Holstein, Hessen-Nassau and Brandenburg there lived considerably more otters per 10 000 ha than in south and east Germany or in the whole of Austria. Using these statistics, one is able to discover those Kreise (in Germany) and Bezirkshauptmannschaften (in Austria), being the smallest territorial unites in each case, with the highest otter potential measured against the hunting area. In the 1880s and 1890s between 6000 and 6500 otters were killed in the German Reich and the German-speaking parts of Austria. In the previous decades of last century and in the first decade of this century, the figure was between 3500 and 4500.

La Loutre (Lutra lutra) à travers les statistiques de chasse allemandes et autrichiennes entre 1830 et 1936
Résumé Un dépouillement des données sur la Loutre(Lutra lutra), contenues dans les statistiques de chasse allemandes et autrichiennes des années 1830 à 1936, s'est fixé pour objectif de rassembler des éléments, à partir des tableaux de tir et de capture, permettant d'évaluer la dynamique et la densité de population de l'espèce. La référence territoriale porte sur quelque 641 000 km correspondant à l'Empire germanique d'avant 1914 et les limites actuelles de l'Autriche. L'évolution de la production de gibier au cours de quelque 6 déciennes révèle un prélèvement accru, économiquement justifié, dans la population de la Loutre au cours des deux dernières décennies de ce siècle; les chiffres de capture et de tir relevés avant et après cette période — connue sous le nom de «période d'invasion de la Loutre» («Ottersturm») —, ne s'écartent cependant pas significativement les uns des autres. Ceci n'exclut pas que des populations locales aient d'ores et déjà pu être décimées; une menace pour l'espèce n'existait pas encore. La régression rapide précédant l'écroulement total de la population de la Loutre ne se consomma qu'à partir de la 2ème à la 4ème décienne du siècle présent et doit être attribuée principalement à l'altération des conditions de milieu. Les chiffres disponibles pour l'étude de la région géographique considérée laissent en outre apparaître une densité de population décroissante du Nord vers l'Ouest, vers le Sud et vers l'Est. En Poméranie, Schleswig-Holstein, Hesse-Nassau et Brandebourg se tenait un nombre beaucoup plus important de loutres par unité de surface de 10 000 ha que dans le Sud et l'Est de l'Allemagne voire même qu'en Autriche. Une interprétation conséquente des données statistiques permet de relever les districts, soit les unités territoriales les plus petites, pour lesquels la production de loutres par territoire de chasse était la plus élevée. Au cours des années 80 et 90 du siècle passé, 6.000 à 6.500 loutres ont été tirées dans l'Empire germanique et dans les régions germanophones de l'Autriche; au cours des décennies antérieures du XIXème siècle et pendant la première décennie du XXème siècle, 3.500 à 4.500 loutres ont été abattues.
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27.
Cerium vanadate films on glass substrate were obtained by sol–gel process. The morphology of these nanostructured and porous films was studied by grazing-incidence small-angle X-ray scattering (GISAXS) at synchrotron ELETTRA, Trieste, Italy. The aim of the GISAXS study was to investigate the changes in grain sizes due to the temperature evolution with three different time intervals (5, 15 and 30 min) of annealing at 673 K. We found that the effects of the different times of annealing are different for surface and bulk properties of this V/Ce oxide.  相似文献   
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