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This paper presents a method that can predict the load variations on propellers of ships that are maneuvering in waves. A two time-scales approach is followed. The method consist of a calm water maneuvering time simulation method and a frequency domain seakeeping method. The mean and low frequent wave drift forces are applied as an external force in the maneuvering simulations. The wave frequent motions and propeller inflow variations are superimposed on the simulation result. These inflow variations are used to predict the propeller thrust and torque variations. The results are compared with model experiments for the DTMB 5415M combatant. The experiments and simulations are in reasonably good agreement. The simulation method can capture several relevant phenomena that are observed in the model experiments.

Heterogeneous catalysis plays a pivotal role in the current chemical and energy vectors production. Notably, to fully utilize the intrinsic activity and selectivity of a catalyst, the chemical reactor has to be designed and operated optimally to achieve enhanced heat/mass transfer, well-defined contact time of reactants, uniform flow pattern, and high permeability. Structured catalysts are a promising strategy to overcome the major drawbacks encountered in the traditional packed-bed reactor technology due to the improved hydrodynamics in combination with enhanced heat/mass transfer. Newly emerged fiber/foam-substrates, with an entirely open 3D network structure, bring distinct advantages over the honeycomb and micro-channel contacting methods, including free radial diffusion, eddy-mixing driven heat/mass transfer, large area-to-volume ratio, and high contacting efficiency. However, how to place the nanocatalysts onto the fiber/foam-substrates is a challenging problem because the commercial washcoating method has great limitations such as the nonuniformity and easy exfoliation of coatings. This review discusses the newly developed non-dip-coating methods for the fiber/foam-structured catalysts and their promising applications in the strongly exo-/endo-thermic and/or high throughput reaction processes., Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., ChemE/Product and Process Engineering, ChemE/Catalysis Engineering

The feasibility of gas phase deposition using a Ti alkoxide precursor for precise surface modification of catalysts was demonstrated by modifying a mesoporous alumina support with a Ti oxide overcoat. Titanium tetra-isopropoxide yields a Ti oxide layer that covers homogeneously the alumina surface. Uniformity of the deposited TiO2 was verified by SEM-EDX, on both intra-particle and inter-particle levels. Only a few atomic layer deposition (ALD) cycles were required in order to obtain Ti contents with a relevance for industrial application. The pore size distribution of the overcoated catalyst support was barely affected by the coating process. Synthesized CoMo catalysts based on the Ti-alumina carrier showed up to 40% higher activity compared to a catalyst supported on pristine alumina, in hydroprocessing under industrial testing conditions. The TiO2 coating appeared to be stable, showing no agglomeration characteristics after reaction as corroborated by TEM-EDX. ALD provides a scalable route with low waste generation for the production of precisely structured TiO2-Al2O3 hydroprocessing catalyst supports., ChemE/Product and Process Engineering

The authors regret that the original graphical abstract contained an error by accident. In particular, the values of the OH density for the calcined SBA-15 and solvent-&-Fenton-treated SBA-15 were swapped. These values contradict the main message of the study. The values contained in the paper are however correct. In summary, the paper's data are correct but the graphical abstract contained swapped data leading to a contradiction. Below, an amended graphical abstract can be found, as well as in the online journal website. The authors would like to apologise for any inconvenience caused. [Figure presented], Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., ChemE/Catalysis Engineering