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The reactive mass transfer around isolated bubbles of pure oxygen rising in a thin‐gap cell filled with acetonitrile at rest is investigated. A colorimetric technique based on the bio‐inspired copper(I) complex [Cu(TMG2tol)]OTf is used. The gap‐ and time‐averaged dissolved oxygen concentration fields can be measured in the far‐wake of the bubbles with 3 < d < 47 mm. The variations of the Sherwood numbers with the Péclet numbers indicate that the mass transfer results obtained are identical with the ones measured earlier with the copper(I) complex [Cu(btmgp)I]. This demonstrates the independency of mass transfer from the properties of the chemical system used. The results significantly enlarge the existing database, which is of great importance to establish robust scaling laws. [ABSTRACT FROM AUTHOR]

Design for deconstruction (DfD) considers the end-of-life scenario of buildings at an early design stage to ensure that these buildings (or parts of the buildings) can be deconstructed without unproportional effort and material loss. After deconstruction, the elements or materials can be used for future purposes such as reusing (preferably), remanufacturing, or recycling. This opinion paper is aimed to advocate for DfD in timber–concrete composite (TCC) floors as it represents an important contribution toward circular economy design and creates a more sustainable built environment. Different end-of-life scenarios for TCC floors according to their original design and connection type were initially explored. Existing deconstructable connection systems that could enable DfD in TCC floors were reviewed. Furthermore, potential challenges relating to the implementation of DfD in TCC floors are briefly highlighted. Finally, a discussion around the outlook and actions that might be needed to address some of the identified challenges is provided. This paper proposes directions for future developments and contributes to the understanding and promotion of DfD in TCC floors with an emphasis on deconstructable connectors that can enable material recovery and reuse as the preferred end-of-life scenario. [ABSTRACT FROM AUTHOR]

Salvaged timber elements often have length limitations, and therefore, their reuse in structural products normally would require additional processing and end-to-end joining. This increases the costs of reusing such materials, which makes them even less attractive to the timber sector. In the presented research, a new approach is proposed for reusing short, salvaged timber elements combined with new (full-scale) timber boards to fabricate dowel-laminated timber (DLT) panels without significant processing or end-to-end joining or gluing. In this approach, salvaged timber elements are pressed in the system in such a way that they can contribute to the bending performance of the DLT panels by resisting compression stress. In order to evaluate the effectiveness, several small-scale and large-scale DLT panels were fabricated. Salvaged plywood tenons were used as connectors. The bending stiffness of the small-scale DLT panels and the first eigenfrequency, damping ratio, bending properties, and failure modes of the large-scale DLT panels were evaluated. The results exhibited that by using the proposed approach, the short, salvaged timber elements can contribute substantially to the bending stiffness of the DLT panels without requiring end-to-end joining or gluing. On average, about a 40% increase in the bending stiffness could be achieved by pressing in the salvaged timber elements, which results in relatively similar stiffness properties compared to conventional DLT panels. One further characteristic is that the failure of the panels, and therefore the panel's strength, is mainly governed by the quality of the full-scale timber boards instead of the salvaged ones. This can be beneficial for practical use as the qualitative assessment of the strength properties of salvaged timber becomes less critical. [ABSTRACT FROM AUTHOR]