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Taking the wide band gap one-dimensional (1-D) tungsten oxide nanowires as an example, we here demonstrate systematically the physical characteristics of thermally processed nanowires at temperatures ranging from 400°C to 1000°C, for the first time. Accompanied by a significant drop of specific surface area from 151 m²/g for the as-prepared nanowires to 109 m²/g and 66 m²/g subject to annealing at 400°C and 450°C, dramatically morphology evolution and phase transformation have also been observed. The nanostructured bundles became straighter, larger in diameters and shorter in length, and eventually became irregular particles with size up to 5 µm. The Brunauer-Emmett-Tettler (BET) result suggests that 400°C can be considered as a top temperature limit in nanodevice design where high surface area is important, e.g. in gas sensors. A protocol for thermally processing of these bundled tungsten nanowires has been established.

The derivation of the standard model from a higher-dimensional action suggests a further study of the fiber bundle formulation of gauge theories to determine the variations in the choice of structure group that are allowed in this geometrical setting. The action of transformations on the projection of fibers to their submanifolds are characteristic of theories with fewer gauge vector bosons, and specific examples are given, which may have phenomenological relevance. The spinor space for the three generations of fermions in the standard model is described algebraically.

Recently, a new gauging procedure called Sculpting mechanism was proposed to obtain the M-theory origin of type II gauged Supergravity theories in 9D. We study this procedure in detail and give a better understanding of the different deformations and changes in fiber bundles that are able to generate new relevant physical gauge symmetries in the theory. We discuss the geometry involved in the standard approach (Noether-like) and in the new Sculpting-like one and comment on possible new applications.

Approaches based on the concept of ecosystem services need analyses of the sets of spatially correlated services (i.e. bundles) and of the external factors that modify the ecosystem service supply (i.e. drivers of change). At present, appropriate methods to analyse bundles and drivers of change are still under development. This study proposes a method based on a combination of spatial and statistical analyses to define bundles and to explain the drivers of change of 24 ecosystem services in Trentino, an Alpine region of Italy. Results show that multiple services can be grouped in a few number of bundles with a complex shape. When mapping multiple services across the territory, the spatial units of representation are a combination of the intrinsic units of representation of single ecosystem services and land use classes. Land use management was found as the external factor that causes the greatest variability of the ecosystem services distribution across the region.

Critical yarning conditions from vertically aligned carbon nanotubes (VACNTs) using a chemical vapor deposition have been investigated. VACNTs with a diameter of around 15 nm have been synthesized with a length up to 3.7 mm. The yarning was realized exclusively in a limited range of the CNT lengths of about 170–1500 μm. Although CNTs became long for longer growth times, some of the CNTs were plucked out from the bottom substrate during growth so that the CNT density decreased at later stages of growth, prohibiting continuous yarning by the suppression of interconnection between CNTs at the bottom part of VACNTs.