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Minaeralization in variably saturated porous media and its consequential changes on effective Diffusivity
No full textDevelopment of a two-dimensional Raman spectroscopy measuring technique for the visualization of mass transfer during droplet formation
No full textA novel two-dimensional Raman spectroscopy measurement setup is developed to visualize mass transfer during droplet formation and applied to the water/acetonitrile/toluene system. This setup enables direct observation of local solute contents. Experiments were conducted using 2 mm and 4 mm droplets with an initial acetonitrile content of 10 wt%. The results are qualitatively consistent with findings reported in the literature for similar systems. Initial calibration measurements using single-phase systems demonstrated linear correlations between measured intensities and solute contents in both phases, though a baseline shift in the organic phase was attributed to the presence of toluene. Applying these correlations to droplet formation experiments resulted in an overestimation of local acetonitrile contents. Future work will focus on further refining the quantification capabilities of the measurement setup
Mapping proton and carbon dioxide electrocatalytic reductions at a Rh complex by in situ spectroelectrochemical NMR
No full textDetailed molecular level understanding of organometallic electrocatalytic systems is required to fully exploit their technological potential to store, distribute, and utilise renewable energy in chemical form. However, in situ methods providing high resolution information on the structure and reactivity of transient intermediates remain challenging due to incompatible requirements for standard electrochemical and spectroscopic cell designs. Here, we demonstrate the use of spectroelectrochemical nuclear magnetic resonance (SEC-NMR) to enable operando characterisation of molecular species during organometallic electrocatalysis. The electroreduction of a prototypical molecular rhodium(+I) diphosphine complex was studied under aprotic conditions and in the presence of H2O and/or CO2. By combining multinuclear SEC-NMR, chemical reductions, modelling and simulations, we determine the involved species, their relative concentrations and the competing interconversions. The bielectronic reduction leading to the highly reactive low-valent rhodium(−I) intermediate and subsequent protonation of that species into a Rh–hydride complex was followed in a time-resolved manner. Deuterium labelling and ex situ NMR analysis after SEC-NMR electrolysis revealed that under aprotic conditions the proton source substantially arises from Hofmann elimination of the nBu4NPF6 electrolyte in addition to the acetonitrile solvent. The reactivities of the Rh(−I) and the Rh–H complexes were further monitored under turnover conditions, providing direct molecular insights into bifurcating electrocatalytic pathways for hydrogen evolution and CO2 reduction
interTwin: Advancing Scientific Digital Twins through AI, Federated Computing and Data
No full textThe EU project interTwin, co-designed and implemented the prototype of an interdisciplinary Digital Twin Engine (DTE), an open-source platform that provides generic and domain-specific software components for modelling and simulation to integrate application-specific Digital Twins (DTs). The DTE is built upon a co-designed conceptual model - the DTE blueprint architecture - guided by open standards and interoperability principles. The ambition is to develop a unified approach to the implementation of DTs that is applicable across diverse scientific disciplines to foster collaborations and facilitate developments. Co-design involved DT use cases from high-energy physics, radio astronomy, astroparticle physics, climate research, and environmental monitoring, which drove advancements in modelling and simulation by leveraging heterogeneous distributed digital infrastructures, enabling dynamic workflow composition, real-time data management and processing, quality and uncertainty tracing of models, and multi-source data fusion
CrIS Code Collection (v1.2)
No full textThis repository provides a collection of codes for the analysis of observations of the Cross Track Infrared Sounder (CrIS)
