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The present study deals with the numerical modelling of hybridlaminated composites, which can be proved especially useful in theengineering and maintenance of advanced aerospace primary structures. Thelamina is comprised of continuous carbon fibers, thermosetting epoxypolymer matrix, as well as carbon nanostructures, such as graphene orcarbon nanotubes, inclusions. Halpin-Tsai equations combined with resultsobtained from nanomechanical analysis are employed in order to evaluatethe elastic properties of the carbon nanostructure/polymer matrix. Then, theobtained elastic properties of the hybrid matrix are used to calculate theorthotropic macro-mechanical properties of the unidirectional compositelamina. A hybrid composite plate is modelled as a 2D structure via theutilization of 4-node, quadrilateral, stress/displacement shell finite elementswith reduced integration formulation. The convergence and analysisaccuracy are tested. The mechanical performance of the hybrid compositesis investigated by considering specific configurations and applyingappropriate loading and boundary conditions. The results are compared withthe corresponding ones found in the open literature, where it is possible.
Tourism is on course to thwart humanity’s efforts to reach a zero carbon economy because of its high growth rates and carbon intensity. To get out of its carbon predicament, the tourism sector needs professionals with carbon literacy and carbon capability. Providing future professionals in the full spectrum of tourism-related study programmes with the necessary knowledge and skills is essential. This article reports on ten years of experience at a BSc tourism programme with a carbon footprint exercise in which students calculate the carbon footprint of their latest holiday, compare their results with others and reflect on options to reduce emissions. Before they start, the students are provided with a handout with emission factors, a brief introduction and a sample calculation. The carbon footprints usually differ by a factor of 20 to 30 between the highest and lowest. Distance, transport mode and length of stay are almost automatically identified as the main causes, and as the main keys for drastically reducing emissions. The link to the students’ own experience makes the exercise effective, the group comparison makes it fun. As the exercise requires no prior knowledge and is suitable for almost any group size, it can be integrated into almost any tourism-related study programme.
While Amazonian forests are extraordinarily diverse, the abundance of trees is skewed strongly towards relatively few ‘hyperdominant’species. In addition to their diversity, Amazonian trees are a key component of the global carbon cycle, assimilating and storing morecarbon than any other ecosystem on Earth. Here we ask, using a unique data set of 530 forest plots, if the functions of storing andproducing woody carbon are concentrated in a small number of tree species, whether the most abundant species also dominate carboncycling, and whether dominant species are characterized by specific functional traits.
MULTIFILE
In this proposal, a consortium of knowledge institutes (wo, hbo) and industry aims to carry out the chemical re/upcycling of polyamides and polyurethanes by means of an ammonolysis, a depolymerisation reaction using ammonia (NH3). The products obtained are then purified from impurities and by-products, and in the case of polyurethanes, the amines obtained are reused for resynthesis of the polymer. In the depolymerisation of polyamides, the purified amides are converted to the corresponding amines by (in situ) hydrogenation or a Hofmann rearrangement, thereby forming new sources of amine. Alternatively, the amides are hydrolysed toward the corresponding carboxylic acids and reused in the repolymerisation towards polyamides. The above cycles are particularly suitable for end-of-life plastic streams from sorting installations that are not suitable for mechanical/chemical recycling. Any loss of material is compensated for by synthesis of amines from (mixtures of) end-of-life plastics and biomass (organic waste streams) and from end-of-life polyesters (ammonolysis). The ammonia required for depolymerisation can be synthesised from green hydrogen (Haber-Bosch process).By closing carbon cycles (high carbon efficiency) and supplementing the amines needed for the chain from biomass and end-of-life plastics, a significant CO2 saving is achieved as well as reduction in material input and waste. The research will focus on a number of specific industrially relevant cases/chains and will result in economically, ecologically (including safety) and socially acceptable routes for recycling polyamides and polyurethanes. Commercialisation of the results obtained are foreseen by the companies involved (a.o. Teijin and Covestro). Furthermore, as our project will result in a wide variety of new and drop-in (di)amines from sustainable sources, it will increase the attractiveness to use these sustainable monomers for currently prepared and new polyamides and polyurethanes. Also other market applications (pharma, fine chemicals, coatings, electronics, etc.) are foreseen for the sustainable amines synthesized within our proposition.
The primary objective of the project is to identify policies for the transformation of the Norwegian tourism sector to become resilient to climate change and carbon risks; to maintain and develop its economic benefits; and to significantly reduce its emissions-intensity per unit of economic output. Collaborative partnersStiftinga Vestlandforsking, Stiftelsen Handelshoyskolen, Stat Sentralbyra, Norges Handelshoyskole, Stiftelsen Nordlandsforskning, Fjord Norge, Hurtigruten, Neroyfjorden Verdsarvpark, Uni Waterloo, Uni Queensland, Desinasjon Voss, Stift Geirangerfjorden Verdsarv, Hogskulen Pa Vestlandet.
The seaweed aquaculture sector, aimed at cultivation of macroalgal biomass to be converted into commercial applications, can be placed within a sustainable and circular economy framework. This bio-based sector has the potential to aid the European Union meet multiple EU Bioeconomy Strategy, EU Green Deal and Blue Growth Strategy objectives. Seaweeds play a crucial ecological role within the marine environment and provide several ecosystem services, from the take up of excess nutrients from surrounding seawater to oxygen production and potentially carbon sequestration. Sea lettuce, Ulva spp., is a green seaweed, growing wild in the Atlantic Ocean and North Sea. Sea lettuce has a high nutritional value and is a promising source for food, animal feed, cosmetics and more. Sea lettuce, when produced in controlled conditions like aquaculture, can supplement our diet with healthy and safe proteins, fibres and vitamins. However, at this moment, Sea lettuce is hardly exploited as resource because of its unfamiliarity but also lack of knowledge about its growth cycle, its interaction with microbiota and eventually, possible applications. Even, it is unknown which Ulva species are available for aquaculture (algaculture) and how these species can contribute to a sustainable aquaculture biomass production. The AQULVA project aims to investigate which Ulva species are available in the North Sea and Wadden Sea which can be utilised in onshore aquaculture production. Modern genomic, microbiomic and metabolomic profiling techniques alongside ecophysiological production research must reveal suitable Ulva selections with high nutritional value for sustainable onshore biomass production. Selected Ulva spp lines will be used for production of healthy and safe foods, anti-aging cosmetics and added value animal feed supplements for dairy farming. This applied research is in cooperation with a network of SME’s, Research Institutes and Universities of Applied Science and is liaised with EU initiatives like the EU-COST action “SeaWheat”.