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Hard X-ray diffraction (XRD) using a nanofocused beam is used to measure both lattice contraction and bending in a single nanowire device under electric bias. The shape of the nanowire is reconstructed in 3D with sub-nanometer precision. As the bias voltage is gradually increased, nonreversible structural changes in the contact regions are observed, correlated with degradation of the electrical co

Simultaneous scanning Bragg contrast and small-angle ptychographic imaging of a single solar cell nanowire are demonstrated, using a nanofocused hard X-ray beam and two detectors. The 2.5 μm-long nanowire consists of a single-crystal InP core of 190 nm diameter, coated with amorphous SiO2 and polycrystalline indium tin oxide. The nanowire was selected and aligned in real space using the small-angl

Hard x-ray focusing and imaging on the few nano metre scale has gained a lot of attraction in the last couple of years. Thanks to new developments in fabrication and inspection of high-N.A. optics, focusing of hard x-rays has caught up with the focusing performance for soft x-rays. Here we review the latest imaging experiments of the Göttinger Multilayer zone plate collaboration, summarising our r

This article describes holographic imaging experiments using a hard X-ray multilayer zone plate (MZP) with an outermost zone width of 10nm at a photon energy of 18keV. An order-sorting aperture (OSA) is omitted and emulated during data analysis by a 'software OSA'. Scanning transmission X-ray microscopy usually carried out in the focal plane is generalized to the holographic regime. The MZP focus

We present a fabrication scheme of contacting arrays of vertically standing nanowires (NW) for LEDs (Duan et al. Nature 409:66–69, 2001), photodetectors (Wang et al. Science (NY) 293:1455–1457, 2001) or solar cell applications (Wallentin et al. Science (NY) 339:1057–1060, 2013). Samples were prepared by depositing Au films using nano-imprint lithography (Ma rtensson et al. Nano Lett 4:699–702, 200

Suitable detection systems that are capable of recording high photon count rates with single-photon detection are instrumental for coherent X-ray imaging. The new single-photon-counting pixel detector 'Lambda' has been tested in a ptychographic imaging experiment on solar-cell nanowires using Kirkpatrick-Baez-focused 13.8 keV X-rays. Taking advantage of the high count rate of the Lambda and dynami

Waveguiding of excitation beam and propagation of THz beam in a complex gradient environment were studied in an array of InP nanowires. Measurements by time-resolved THz spectroscopy accompanied by Monte-Carlo calculations of the response of localized charges enabled determination of transversal electron mobility.

Chemical building blocks for plastics can be produced from renewable biomass feedstocks using microbial production organisms, such as yeast or bacteria, in a biorefinery. One class of chemical building blocks that are suitable for production of biobased and biodegradable plastics are dicarboxylic acids, e.g. succinic acid. In order to avoid competition with food and feed production it is desirable

The degradation of the chemotherapy drug 5-fluorouracil by a non-pristine metal surfaces is studied. Using density functional theory, X-ray photoelectron spectroscopy and X-ray absorption spectroscopy we show that the drug is entirely degraded by medical-grade silver surfaces, already at body temperature, and that all of the fluorine has left the molecule, presumably as HF. Remarkably, this degrad

Cereal β-glucan is well known for its beneficial health effects, such as lowering of blood cholesterol values and a reduced risk of coronary heart disease. These effects are often discussed in relation to the dissolution and aggregation behavior of the β-glucan during human digestion. Furthermore, potential proteinaceous material present is believed to have an important impact on the formation of

Fires including flammable gases and/or liquids differ from typical residential fires where the fuel is mainly composed of solid combustibles. The traditional ISO 834 curve was established to represent the timetemperature curve for a fully developed fire. However for combustible gases the type of thermal exposure might be substantially different and therefore other curves have been developed such a

Upholstered furniture is a major contributor to the fuel load in a fire compartment. Modelling the fire behaviour of upholstered furniture would support performance based fire safety engineering, by allowing the specification of realistic fire scenarios. Modelling upholstered furniture composites in cone calorimeter test conditions is undertaken to validate fundamental assumptions about the fire b

A report on a panel convened by the Nordic Association for Romantic Studies at the 'Romanticism Takes to the Hills' conference at Edge Hill University (UK), 29 April 2017

Rare earth elements are strategic commodities in many countries, and an important resource for the growing modern technology industry. As such, there is an increasing interest for development of rare earth element processing, and this work is a part of further development of chromatography as a rare earth element separation process method. Process optimization is pivotal for process development, Rare earth elements are strategic commodities in many countries, and an important resource for the growing modern technology industry. As such, there is an increasing interest for development of rare earth element processing, and this work is a part of further development of chromatography as a rare earth element separation process method. Process optimization is pivotal for process development, a

The combination of coagulation/flocculation and discfiltration with ozonation to reduce nutrients and organic micro-pollutants in secondary effluent was studied in pilot scale at Lundåkraverket wastewater treatment plant in Landskrona, Sweden. With a chemical dose of 4 gAl3þ/m3 and 1.5 g/m3 cationic polymer as active material effluent water quality with regards to total phosphorous (Tot-P), suspenThe combination of coagulation/flocculation and discfiltration with ozonation to reduce nutrients and organic micro-pollutants in secondary effluent was studied in pilot scale at Lundåkraverket wastewater treatment plant in Landskrona, Sweden. With a chemical dose of 4 gAl3+/m3 and 1.5 g/m3 cationic polymer as active material effluent water quality with regards to total phosphorous (Tot-P), suspen

Pilot-scale tests were run with ozonation for reduction of 24 pharmaceuticals at 10 full-scale wastewater treatment plants in southern Sweden. Reduction was evaluated based on doses of 3, 5 and 7 g O3/m3 at all plants. The reduction of pharmaceuticals reached on average 65% at 3 g O3/m3, 78% at 5 g O3/m3 and 88% for 7 g O3/m3 in terms of total concentration of pharmaceuticals. Specific ozone dose Pilot-scale tests were run with ozonation for reduction of 24 pharmaceuticals at 10 full-scale wastewater treatment plants in southern Sweden. Reduction was evaluated based on doses of 3, 5 and 7 g O3/m3 at all plants. The reduction of pharmaceuticals reached on average 65% at 3 g O3/m3, 78% at 5 g O3/m3 and 88% for 7 g O3/m3 in terms of total concentration of pharmaceuticals. Specific ozone dose