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An effective route is developed to fabricate ultrathin rhenium diselenide (ReSe2) nanosheets anchored on reduced graphene oxide (rGO) nanoflakes (ReSe2@rGO). When the ReSe2@rGO is used as an anode material in the potassium-ion batteries (PIBs), the graphene offers a conductive matrix to buffer the volume alteration during repeated K+ insertion/extraction cycles. The stable interfacial connection between ReSe2 and graphene greatly promotes the integration of the active ReSe2 nanosheets, preventing their agglomeration. At the same time, these ultrathin nanosheets shorten the ion/electron diffusion path, leading to stable cyclic performance. As a result, the ReSe2@rGO anode enhances the electrochemical performance of the as-synthesized PIB with a high specific capacity of over 250 mAh g-1 at a current density of 500mA g-1 even after 200 cycles. Excellent rate performance and lengthy cyclic performance with 150 mAh g-1 at 2 A g-1 are also observed even after 500 cycles. [ABSTRACT FROM AUTHOR]

A new type of a mesoporous carbon-coated bismuth (Bi@C) composite in the form of nanorods is fabricated and used as anode material in a potassiumion battery (KIB). The rod-like Bi core is composed of nanoparticles and confined by a shell of amorphous carbon. The KIB with such Bi@C anode exhibits a high storage capacity of 425 mAh g-1 at 0.2 A g-1. The mesoporous Bi@C, with a large surface area and an appropriate pore size is in close contact with the electrolyte and facilitates the diffusion of K+ ions. The carbon shell soothes the mechanical stresses owing to the volumetric changes of the anode during charging and discharging of the battery, preventing the degradation of active material and delivering a cyclic stability of over 500 cycles. This superior performance demonstrates the importance of a structural design that can offer a new pathway to anode development in KIB as well as in other energy storage devices. [ABSTRACT FROM AUTHOR]

The article focuses on the necessity of adapting cartographic design to mobile devices due to the predominant use of maps on such platforms today. It reports that the traditional cartographic canon designed for printed maps needs to evolve to cater to the constraints and user experience considerations of mobile devices, and it emphasizes a mobile-first design philosophy.

Road networks are important for modelling the urban geographic environment. It is necessary to determine the spatial relationships of road intersections when using maps to help researchers conduct virtual urban geographic experiments (because a road intersection might occur as a connected cross or as an unconnected bridge overpass). Based on the concept of using different map layers to organize the render order of each road segment, three methods (manual, semi-automatic and mask-based automatic) are available to help map designers arrange the rendering order. However, significant efforts are still needed, and rendering efficiency remains problematic with these methods. This paper considers the Discrete, Crossing, Overpass, Underpass, Conjunction, Up-overlap and Down-overlap spatial relationships of road intersections. An automatic method is proposed to represent these spatial relationships when drawing road networks on a map. The data-layer organization method (reflecting road grade and elevation-level information) and the symbol-layer decomposition method (reflecting road covering order in the vertical direction) are designed to determine the rendering order of each road element when rendering a map. In addition, an "auxiliary-drawing-action" (for drawing road segments belonging to different grades and elevations) is proposed to adjust the rendering sequences automatically. Two experiments are conducted to demonstrate the feasibility and efficiency of the method, and the results demonstrate that it can effectively handle spatial relationships of road networks in map representations. Using the proposed method, the difficulty of rendering complex road networks can be reduced. [ABSTRACT FROM AUTHOR]