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Coherent X-ray imaging techniques, such as in-line holography, exploit the high brilliance provided by diffraction-limited storage rings to perform imaging sensitive to the electron density through contrast due to the phase shift, rather than conventional attenuation contrast. Thus, coherent X-ray imaging techniques enable high-sensitivity and low-dose imaging, especially for low-atomic-number (Z) chemical elements and materials with similar attenuation contrast. Here, the first implementation of in-line holography at the NanoMAX beamline is presented, which benefits from the exceptional focusing capabilities and the high brilliance provided by MAX IV, the first operational diffraction-limited storage ring up to approximately 300 eV. It is demonstrated that in-line holography at NanoMAX can provide 2D diffraction-limited images, where the achievable resolution is only limited by the 70 nm focal spot at 13 keV X-ray energy. Also, the 3D capabilities of this instrument are demonstrated by performing holotomography on a chalk sample at a mesoscale resolution of around 155 nm. It is foreseen that in-line holography will broaden the spectra of capabilities of MAX IV by providing fast 2D and 3D electron density images from mesoscale down to nanoscale resolution.

Many buildings built in the 1960s are inefficient when it comes to their energy use. A lot of them are also in need of renovating. Therefore, this project is aiming to investigate five different scenarios where the decrease in electricity demand is in focus.One scenario is energy-saving behavior which does not need any investment for a renovation but just decreases the electricity demand by changing the behavior of the people living there.Another option is the building envelope renovation where added insulation to the outer walls, the roof and the floor is added. The windows and entrance doors are also upgraded to more efficient options. A return air only ventilation system is installed as well. The third option is to renovate the reference house to achieve the status of passive house set by Boverket. This is done by adding a much thicker layer of insulation to the building components and adding a FTX ventilation system and at the same time changing the direct electric heating system to a bed rock geothermal heating system. The last two scenarios, net-zero energy building and off-grid building, also use a FTX ventilation system and bed rock geothermal heating system. They have the same thickness as the building envelope renovation. The biggest difference is that the net-zero energy building uses solar power to match the yearly electricity demand and therefore be able to call it net-zero energy. The off-grid house has an electricity storage as well as the solar panels. This is to be able to disconnect from the electric grid completely and only consume electricity produced by the building itself.The last three scenarios all achieve a primary energy below that of what Boverket demand fornew buildings of 90 kWh/m^2, year. The building with the lowest cumulative cost over 50 years is the off-grid building, though this result could vary depending on the price of electricity. The scenario with the lowest investment cost per kWh saved is the net-zero energy building.

Scientific reports 9(1), 3435 (2019). doi:10.1038/s41598-019-39934-4, Biomaterials often display outstanding combinations of mechanical properties thanks to theirhierarchical structuring, which occurs through a dynamically and biologically controlled growth andself-assembly of their main constituents, typically mineral and protein. However, it is still challenging toobtain this ordered multiscale structural organization in synthetic 3D-nanocomposite materials. Herein,we report a new bottom-up approach for the synthesis of macroscale hierarchical nanocompositematerials in a single step. By controlling the content of organic phase during the self-assembly ofmonodisperse organically-modified nanoparticles (iron oxide with oleyl phosphate), either purelysupercrystalline or hierarchically structured supercrystalline nanocomposite materials are obtained.Beyond a critical concentration of organic phase, a hierarchical material is consistently formed. In sucha hierarchical material, individual organically-modified ceramic nanoparticles (Level 0) self-assembleinto supercrystals in face-centered cubic superlattices (Level 1), which in turn form granules of up tohundreds of micrometers (Level 2). These micrometric granules are the constituents of the final mmsizedmaterial. This approach demonstrates that the local concentration of organic phase and nanobuildingblocks during self-assembly controls the final material’s microstructure, and thus enables thefine-tuning of inorganic-organic nanocomposites’ mechanical behavior, paving the way towards thedesign of novel high-performance structural materials., Published by Springer Nature, London

Data in Brief 21, 1924 - 1936 (2018). doi:10.1016/j.dib.2018.10.076, This data article describes the detailed parameters for synthesizing mullite inverse opal photonic crystals via Atomic Layer Deposition (ALD), as well as the detailed image analysis routine used to interpret the data obtained by the measurement of such photonic crystals, before and after the heat treatment, via Ptychographic X-ray Computed Tomography (PXCT). The data presented in this article are related to the research article by Furlan and co-authors entitled “Photonic materials for high-temperature applications: Synthesis and characterization by X-ray ptychographic tomography” (Furlan et al., 2018). The data include detailed information about the ALD super-cycle process to generate the ternary oxides inside a photonic crystal template, the raw data from supporting characterization techniques, as well as the full dataset obtained from PXCT. All the data herein described is publicly available in a Mendeley Data archive “Dataset of synthesis and characterization by PXCT of ALD-based mullite inverse opal photonic crystals” located at https://data.mendeley.com/datasets/zn49dsk7x6/1 for any academic, educational, or research purposes., Published by Elsevier, Amsterdam [u.a.]

24th International Congress on X-ray Optics and Microanalysis, ICXOM24, Trieste, Italy, 25 Sep 2017 - 29 Sep 2017, Nanoporous gold (NPG) is the structure resultant from dealloying an Ag-rich AgAu alloy. It displays a high specific surface area, high electrical conductivity and good mechanical properties, making it very interesting for sensing and actuating applications [1]. The structural length-scales of NPG can be tailored to different structural thicknesses ranging from 20 nm up to 1 μm, which allows a tailorable mechanical response [2]. Recent Focused Ion Beam (FIB) based tomography measurements have identified critical topological characteristics shown to correlate to mechanical response [1-2]. However, the destructive nature of the method negates the possibility to investigate the evolution of the network structure with deformation. X-ray Tomographic Microscopy (XTM) on the other hand allows for in situ observation of the 3D nanostructural evolution during mechanical testing. Since gold is high absorbing for X-rays, NPG is also an optimal sample for evaluating the capability of an XTM setup.A NPG sample was scanned with XTM at the P05 beamline at Petra III, to determine the inner structure of the sample. One major challenge in XTM is the overall stability of the setup, e.g. to minimize sample drifts and time-induced shifts from e.g. the motorized sample stages. In order to achieve the best possible data reconstruction even small shifts have to be corrected for. Therefore, projection images were first corrected for horizontal and vertical shifts [3], whereinafter the data was reconstructed with TomoPy, using an iterative reconstruction algorithm [4]. Morphological structure parameters such as Percentage Volume (VV), Structure thickness (St.Th), Specific Surface Area (SV) of NPG were evaluated using Pore3d [5] and compared to parameters obtained by FIB based tomography [2]. NPG is an optimal material for evaluating and improving the capabilities of the XTM setup at the P05 Beamline at PETRA III, which will also be presented more in detail.

¨This thesis focuses on evaluating the dual-modal Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) capabilities of contrast agents. For such purposes a gadolinium based contrast agent is of high interest, due to its paramagnetic properties, which while present inside a magnetic field will hence interact with the protons spins of water (in tissue and fat) and shorten their the T1 relaxation time, thereby creating a positive image contrast in MRI. Furthermore, the X-ray Mass Attenuation Coefficient (MAC) of gadolinium is relatively high, thus suggesting its potential use, also as a CT contrast agent. Gadolinium nanoparticles (GdNPs) can be loaded into cells, such as macrophages, which offers the possibility to track cells inside entire organisms. In the first step the uptake of GdNPs inside cells was investigated, together with a test for toxicity. To show the potential of using GdNP loaded macrophages for functional imaging of inflammation, an acute allergic airway inflammation mouse model (mimicking asthma in humans) was used and analyzed by in-situ synchrotron phase contrast CT. In the first step this approach was evaluated using macrophages loaded with a clinical contrast agent containing barium sulphate (BaSO4), since this agent is known to provide high contrast in CT. In the ultimate step a combination of both BaSO4 and GdNP loaded macrophages was used in the same asthmatic mouse model and analyzed by dual modal Synchrotron phase contrast CT and Micro Magnetic Resonance Imaging (μ-MRI). Complementary results in terms of the biodistribution of injected macrophages could only be obtained by the combination of both synchrotron phase contrast CT and μ-MRI, where the first modality allows a detailed localization of clustered BaSO4 loaded macrophages, but fails to detect single macrophages, which could instead be indirectly observed by μ-MRI as an increase of the T1-contrast, coming from the soft tissue of mice injected with GdNP loaded macrophages.

The study of internal structure of materials has always been an essential issue in a variety of application fields, from the medical radiology to the materials science. X-ray computed microtomography (with both conventional and synchrotron radiation sources) has a great potential for these purposes because its three-dimensional and non destructive nature as well as the fact that it does not require any sample preparation and it allows to study samples under stress or after consecutive treatments. The recent developments of new X-ray sources with innovative imaging techniques, as well as novel high resolution detectors, allow moving forward the maximum achievable resolution of this technique to a few micrometers or even less. This contributed to increase its application in biomedical purposes, but also to raise the need for quantitative analysis of the reconstructed data. Indeed in most of the cases a quantitative characterization of the samples microstructures is needed to better understand their physical and chemical behavior, the effects of manufacturing process or the response to stress. Dedicated software packages have been developed to perform a geometrical and morphological characterization of the samples texture and to evaluate some typical parameters commonly used to classify porous media such as porosity, cell size distribution, connectivity and anisotropy. In this work two case studies have been considered for the application of a quantitative analysis approach to microtomography datasets: the first concerns the characterization of bone ingrowth within tissue engineering scaffolds, while the second is related to the extraction of morphological descriptors for the architecture of human skull bones. It will be shown how suitable image processing and analysis techniques are able to effectively quantify significant parameters such as the trabecular thickness of the skull bones as well as the porosity and the degree of connectivity of bone tissue engineering scaffolds. Similar quantitative analysis methods applied to microtomography images have to be considered as an effective methodology for a comprehensive characterization of other biomedical samples.