High-pressure 155Gd Mössbauer experiments on Gd intermetallic compounds compared with first-principles band-structure calculations

Surface and quantum-size effects in Pt and Au nanoparticles probed by 197Au Mössbauer spectroscopy

Behaviour of a falling apron made from 'poorly sorted' material

This thesis is about the behaviour of a falling apron made from 'poorly sorted' material. It is a follow-up of a report, which was made by a Dutch student, Marc van der Hoeven, with the title: "The behaviour of a falling apron". In the end of the last century a complex river training work had to be done in con- nection with the construction of...

A new view on falling aprons

In a flume of BallastHam Dredging a falling apron model has been constructed and loaded by current. The tests have been done with different rock sizes, different layer thickness of the top storage of the apron and two different gradings. In summary it was found that for both the narrow graded rock layers as well as for wide graded riprap the...

Electron postgrowth irradiation of platinum-containing nanostructures grown by electron-beam-induced deposition from Pt(PF3)4

The material grown in a scanning electron microscope by electron beam-induced deposition (EBID) using Pt(PF3)4 precursor is shown to be electron beam sensitive. The effects of deposition time and postgrowth electron irradiation on the microstructure and resistivity of the deposits were assessed by transmission electron microscopy, selected area...

Astrobiology and habitability studies in preparation for future Mars missions: Trends from investigating minerals, organics and biota

Several robotic exploration missions will travel to Mars during this decade to investigate habitability and the possible presence of life. Field research at Mars analogue sites such as desert environments can provide important constraints for instrument calibration, landing site strategies and expected life detection targets. We have...

Nepantla, the village in the city

Understanding the carbonation of concrete with supplementary cementitious materials: a critical review by RILEM TC 281-CCC

Blended cements, where Portland cement clinker is partially replaced by supplementary cementitious materials (SCMs), provide the most feasible route for reducing carbon dioxide emissions associated with concrete production. However, lowering the clinker content can lead to an increasing risk of neutralisation of the concrete pore solution and...

Measurement of the thulium ion spin Hamiltonian in an yttrium gallium garnet host crystal

We characterize the magnetic properties for thulium ion energy levels in the (Tm:YGG) lattice with the goal to improve decoherence and reduce linewidth broadening caused by local host spins and crystal imperfections. More precisely, we measure hyperfine tensors for the lowest level of and excited states using a combination of spectral hole...

Optical coherence and energy-level properties of a Tm3+ -doped LiNb O3 waveguide at subkelvin temperatures

We characterize the optical coherence and energy-level properties of the 795-nm H63 to H43 transition of Tm3+ in a Ti4+:LiNbO3 waveguide at temperatures as low as 0.65 K. Coherence properties are measured with varied temperature, magnetic field, optical excitation power and wavelength, and measurement timescale. We also investigate nuclear...

Quadratic Zeeman spectral diffusion of thulium ion population in an yttrium gallium garnet crystal

The creation of well-understood structures using spectral hole burning is an important task in the use of technologies based on rare-earth ion-doped crystals. We apply a series of different techniques to model and improve the frequency dependent population change in the atomic level structure of thulium yttrium gallium garnet (Tm:YGG). In...

The Role of Education and Science-Driven Tools in Scaling Up Photovoltaic Deployment

Accelerating the deployment of Photovoltaic (PV) systems is a key contributing factor in achieving climate neutrality. Even though solar power is one of the cheapest energy sources and its deployment is growing rapidly around the world, an even faster growth is required to achieve existing climate goals. Besides the role that finance and...