This thesis focuses on the X-ray spectral analysis of merging galaxy clusters and the plasma code development for future high-resolution X-ray spectroscopy observations.

Promotor: A. Achúcarro Co-promotor: A. Boyarsky

Visualizing the internal structure is a crucial step in acquiring knowledge about the origin, state, and composition of cultural heritage artifacts. Among the most powerful techniques for exposing the interior of cultural heritage objects is computed tomography (CT), a technique that computationally…

Promotor: J.S. Kaastra Co-promotor: E. Constantini

In this thesis, we present new laboratory data of interstellar dust analogues.

This thesis surveys the intersection of computed tomography (CT) and machine learning (ML), treating CT as an ill-posed inverse problem shaped by object properties, imaging physics, and data limitations.

Hot astrophysical plasma is ubiquitous in the Universe, from comets in our Solar system to the largest scale structures -- the cosmic web filaments. These hot plasmas, with the temperature of a few millions of degrees, are often observed in the X-ray wavelength range.

This thesis examines silicon pore optics (SPO), a technology that exploits silicon wafers from the semiconductor industry to create extremely high quality X-ray optics, by studying its manufacturing process, applications, and prospects.

The overall theme of this thesis is to complement the electrochemical data acquired in fuel cell research with in situ X-ray photoelectron spectroscopy (XPS) and soft X-ray absorption spectroscopy (XAS).

I have studied the hot, diffuse gas around and between galaxies. Specifically, I have used the EAGLE numerical simulations of galaxy formation to predict the properties of this gas, and I have used those properties to predict specific observables: soft X-ray absorption and emission lines.

The intracluster medium (ICM) is a hot, tenuous and X-ray emitting gas that pervades galaxy clusters.

Forming at the nodes of the Cosmic Web and growing hierarchically via mass accretion, galaxy clusters are the largest virialized halos in our universe, composed of dark matter (DM; ≥85%), ionized hot plasma in the intracluster medium (ICM; ≥10-15%), and galaxies (≥1-5%).

Pulsars were first discovered in 1967 and since then the population has grown and expanded over several wavelengths.

The largest structures in the Universe are clusters of galaxies. Each can contain hundreds to thousands of galaxies.

Promotor: Prof.dr. M. Ubbink

Promotor: J.W.M. Frenken Co-Promotor: R. Felici

Promotor: Jelle S. Kaastra Co-promotor: Jelle de Plaa

Humanity stands at a pivotal juncture, facing the dual challenge of environmental sustainability and rapid population growth, projected to exceed 11 billion by century’s end.

This thesis comprises the development of reproducible synthesis procedures for two-dimensional materials (composed of boron, nitrogen and carbon) on different metallic surfaces.

Promotor: Prof.dr. J.W.M. Frenken

Nowadays, it is well known that hydrogen and helium (and small traces of lithium and beryllium) were created shortly after the Big Bang, while the heavier elements are created in the cores of stars at different evolutionary stages. When these stars explode as supernovae, they expel metals synthesised…

The research aims to explore the evolutionary adaptability of enzymes and the impact of temperature on protein evolution pathways, using M. tuberculosis β-lactamase BlaC as the object of study. Enzymes inherently embody a delicate balance between activity and stability, and the acquisition of new enzymatic…

Following the Big Bang, structure in the Universe started collapsing under the force of gravity. This resulted in the formation of the first stars, galaxies and clusters of galaxies.

It has now been well established that shocks and turbulent motions in the intra-cluster medium (ICM) generated through cluster mergers can produce large-scale synchrotron emission.

Promotor: K.J. Batenburg

Radiography is an important technique to inspect objects, with applications in airports and hospitals. X-ray imaging is also essential in industry, for instance in food safety checks for the presence of foreign objects.

Promotor: J. A. Bouwstra

The lipids in the uppermost layer of the skin, the stratum corneum (SC), play an important role in the skin barrier function. The three main SC lipid classes are ceramides (CER), cholesterol and free fatty acids.

The confinement of molecular catalysts in metal-organic frameworks has the potential to lead to significant improvements in selectivity, long term activity and catalyst stability.

The origin and evolution of galaxies are closely linked to many different physical phenomena.

In this thesis, I studied the origin and evolution of the non-thermal radiation in merging galaxy clusters.

Promotor: Prof. dr. A.G.G.M. Tielens

In this thesis, topics relating to the optimization of high-throughput pipelines used for imaging are discussed. In particular, different levels of implementation, i.e., conceptual, software, and hardware, are discussed and the thesis outlines how advances on each level need to be made to make gains…

Cathodic corrosion is a relatively unknown phenomenon that can severely etch metallic electrodes at cathodic (negative) potentials.

Promotor: W. Jaffe, Co-promotor: K. Meisenheimer

This thesis focus on the interaction between M dwarf stellar winds and Galactic cosmic rays and the possible effects on the habitability of exoplanets.

Tomography is a powerful technique to non-destructively determine the interior structure of an object.Usually, a series of projection images (e.g.\ X-ray images) is acquired from a range of different positions.

Promotores: S.F. Portegies Zwart, E. M. Rossi

In this thesis, I study the formation of large-scale structure and the physics of particle acceleration at large scales (~Mpc).

The research in this thesis is focused on tomographic reconstruction based on two imaging modalities in electron microscopy.

Promotor: K.J. Batenburg, Co-promotor: A.W. van der Vaart, B. de Smit

Hydrodesulfurization (HDS) is an ubiquitous part of oil refining that ensures that fuels are cleaned of impurities and environment release of pollutants such as SOx and NOx gasses are minimized.

Promotor: Prof.dr. J.P. Abrahams, Co-Promotor: N.S. Pannu

Promotor: R. Tijdeman, Co-promotor: H.J.J. te Riele

In surface science there is great effort to move from studying simple, flat model surfaces in vacuum to investigating more complex model catalysts in gas environments (in situ). This thesis gives three examples of such studies using microscopy and spectroscopy.

Computers worden steeds krachtiger en krijgen steeds ingewikkelder taken. Het Leiden Institute of Advanced Computer Science (LIACS) doet baanbrekend wetenschappelijk onderzoek en past nieuwe vindingen toe in actuele maatschappelijke vraagstukken.