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We present an approach towards four dimensional (4d) movies of materials, showing dynamic processes within the entire 3d structure. The method is based on tomographic reconstruction on dynamically curved paths using a motion model estimated by optical flow techniques, considerably reducing the typical motion artefacts of dynamic tomography. At the same time we exploit x-ray phase contrast based on

Metallic cast components inevitably contain defects such as shrinkage cavities which are inherent to the solidification process. Those defects are known to significantly alter the fatigue life of components. Yet very little is known, quantitatively, on the dangerosity of internal casting defects compared to surface ones. In this study, fatigue specimens containing controlled internal defects (shri

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Water drainage from porous media is a highly dynamic process often marked by rapid piston-like air invasion events at the front and other rapid interfacial reconfigurations. Liquid phase entrapped behind the moving front drains at significantly slower rates often via gravity driven flow through corners and crevices. This distribution of slowly draining residual water phase determines the plant ava

Series of fast synchrotron X-ray tomographies are taken continuously at a rate of up to 5Hz, while aluminium alloy precursors are foamed in an X-ray transparent setup for several minutes using infra-red (IR) lasers for heating. The entire foaming process from the solid precursor to the expanded liquid foam is captured. The analysis of the sequence of tomographies is done with an emphasis on nuclea

Ductile failure of three 6xxx serie aluminium alloys has been characterized and modelled for about thirty hardening conditions each. These alloys involve relatively similar composition and volume fraction of second phase particles. The tensile mechanical properties show the expected decrease of fracture strain with increasing strength but also major differences among the different alloys with a fa

The complexity of microwave heating stems to a large extent from the intrinsic complexity of the materials exposed to microwave irradiation. For simple ideal homogeneous material, its size, shape and orientation with respect to the electromagnetic field influence the microwave absorption properties at the macroscopic scale. Furthermore, a number of material parameters, namely the complex permittiv

Visualizing fast micrometer scale internal movements of small animals is a key challenge for functional anatomy, physiology and biomechanics. We combine phase contrast tomographic microscopy (down to 3.3 μm voxel size) with retrospective, projection-based gating (in the order of hundreds of microseconds) to improve the spatiotemporal resolution by an order of magnitude over previous studies. We de

In butterflies, bees, flies and true bugs specific mouthparts are in close contact or even fused to enable piercing, sucking or sponging of particular food sources. The common phenomenon behind these mouthpart types is a com-plex composed of several consecutive mouthparts which structurally interact during food uptake. The single mouthparts are thus only functional in con-junction with other adjac

Dual-energy or K-edge imaging is used to enhance contrast between two or more materials in an object and is routinely realised by acquiring two separate X-ray images each at different X-ray wavelength. On a broadband synchrotron source an imaging system to acquire the two images simultaneously was realised. The single-shot approach allows dual-energy and stereo imaging to be applied to dynamic sys

Abstract The microstructure of porous silver layers produced under different low temperature pressure-assisted sintering conditions is characterized and linked with the mechanical behavior studied insitu during X-ray diffraction. Peak profile analysis reveals important strain recovery and hardening mechanism during cyclic deformation. The competition between both mechanisms is discussed in terms o

Visible light Zernike phase contrast (ZPC) microscopy is a well established method for imaging weakly absorbing samples. The method is also used with hard x-ray photon energies for structural evaluation of material science and biological applications. However, the method suffers from artifacts that are inherent for the Zernike image formation. In this Letter, we investigate their origin and experi

Spiral decorated Iron Age Scottish glass beads are a group of highly decorated objects about which very little is known. Despite considerable debate in the past, their technical complexity and elaborate design have always hindered the understanding of their method of production. The innovative application of X-ray micro-computed-tomography (μCT), with synchrotron light, rendered detailed informati

When projects are used as an organisational platform to conduct business, a project can be the only project in the organisation or one amongst several others. The latter case is called multi-project organisation. Usually an organization with a multi-project environment has a base organisation, which can be functional, matrix structure or another. The purpose of this article is to develop a model b

Recently, decreased levels of apolipoprotein M (ApoM) were shown to be associated with higher risk of recurrent venous thromboembolism (VTE) in male patients. However, the role of ApoM in primary VTE is unknown. We aimed in our study to analyze the plasma levels of ApoM in patients with VTE in order to evaluate the diagnostic importance of ApoM in primary VTE. A total of 357 patients with suspecte