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We report on the preparation and characterization of two dimensional (2D) films of (S,S,P)-1 and (R,R,M)-1ortho-oligophenylene ethylene (o-OPE) enantiomers presenting high values of circularly polarized luminescence (CPL). The amphiphilic character of these two molecules allows a precise 2D self-assembly at the air/water interface and an efficient transfer onto a glass solid support. The morphological and chiroptical characterization of the solid supports after the transfer of 1, 8, 16 and 32 Langmuir films of (S,S,P)-1 and (R,R,M)-1 has been carried out. The strong chiroptical values of these monomers allow reliable ECD measurements to be obtained after a single transfer, with ECD values increasing as the number of transferred films increases. The semi-liquid behavior of the monomers on the solid substrate allows CPL measurements free of photoselection artifacts that show values similar to those obtained in solution and independent of monomer concentration. All these properties have allowed us to develop the first simple organic molecule (SOM)-based chiroptical barcoding presenting positive and negative regions as a proof of concept.

Rail freight transport is a key economic activity; many businesses and people rely on it. It should be available when needed and efficient in use. There are however factors that may reduce the availability and quality of a rail freight service offering. A distinction can be made between what may be called systemic factors, like congestion, accidents and technical failures, and external factors like weather conditions and natural disasters. Rail infrastructure managers and users of rail services have learned from experience to anticipate or adapt to systemic factors. They are, to some extent, also able to cope with certain weather conditions. A rather different situation occurs when the weather becomes more extreme and less predictable. Water management systems are usually not developed for excess amounts of rain and hence will fail. Terrestrial water can turn into a devastating flood that may (temporarily) incapacitate railway infrastructure. With this (partially) out of service, freight trains have to be rerouted. This may lead to severe delays, additional costs and externalities, in particular more emissions. This paper deals with the question: What are options for governments to make rail freight transport more resilient to disruptions triggered by climate change, while limiting the externalities caused by rerouting? The paper is an extension of earlier research on this topic. Methods used in the research were a case study, the data of which were fed into a simulation model, which was used to estimate route length, fuel consumption and emissions. The main outcome of the study is that there are interesting options to make rail freight transport networks more resilient. In order to reap their benefits, interoperability should be improved considerably.

To face unmet energy demands, the search for more stable, low-cost, and scalable electrocatalyst materials is imperative. Within this context, single-atom catalysts (SACs) have drawn considerable attention due to their maximum atom utilization. With this idea in mind, we have synthesized a new ultrathin and water-stable 2D Cu-based metal-organic framework (2DCIFs), which presents a notable electrocatalytic activity for oxygen reduction reaction (ORR) in alkaline media without the need of calcination, which makes the difference when compared to most MOF-based electrocatalysts. The designed MOF-based SAC consists of single-atom sites (isolated and accessible Cu) coordinated to imidazole carboxylic ligands, giving rise to Cu-N4O actives sites confined into a 2D-nanostructured network. This unique structure, along with the ultrathin nature of nanosheets that favors mass transport and electrical conductivity, and the high chemical stability of these 2DCIFs are the key features of the excellent ORR performance, which occurs by a direct four-electron transfer pathway, an onset potential of 0.86 V vs RHE and a maximum current density of 6.4 mA·cm-2. These good catalytic properties of 2DCIFs have allowed their use as efficient air electrodes in alkaline flooded and all-solid-state Zn-air batteries. In the former case, 2DCIFsbased air electrodes presented a specific power density of 91.2 kW·cm-2·kg-1 and a specific capacity of 296.2 A·h·g-1, significantly exceeding the specific capacity values reported previously for other Cu-based catalysts. Besides, the specific capacity increased to 389.1 A·h·g-1 when 2DCIFs were tested in an all-solid-state Zn-air battery.