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Progress on multi-order hard x-ray imaging with multilayer zone plates

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

Towards multi-order hard X-ray imaging with multilayer zone plates

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

Processing and characterization of nanowire arrays for photodetectors

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

High-flux ptychographic imaging using the new 55 μm-pixel detector 'Lambda' based on the Medipix3 readout chip

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

Dicarboxylic acids from xylose, using natural and engineered hosts

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

Degradation of the chemotherapy drug 5-fluorouracil on medical-grade silver surfaces

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

Interaction between cereal β-glucan and proteins in solution and at interfaces

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

Analysis of fire barriers with respect to fires with combustible gases and liquids

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

Experimental and numerical investigation on fire behaviour of foam/fabric composites

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

Robust Multi-Objective Optimization of Chromatographic Rare Earth Element Separation

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

Discfiltration and ozonation for reduction of nutrients and organic micro-pollutants from wastewater - a pilot study

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

Removal of pharmaceuticals with ozone at 10 Swedish wastewater treatment plants

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

Application of ozone in wastewater treatment : Oxidation of pharmaceuticals and filamentous bulking sludge

As pharmaceutical removal was not part of the of the modern wastewater treatment plant (WWTP) design, it is not surprising that WWTPs have been identified as major point sources of pharmaceuticals entering the environment. The oxidation of pharmaceuticals in the WWTP effluent is one of the-end-of-pipe solutions that are considered most ready for full-scale use. However, there are several aspects oAs pharmaceutical removal was not part of the of the modern wastewater treatment plant (WWTP) design, it is not surprising that WWTPs have been identified as major point sources of pharmaceuticals entering the environment. The oxidation of pharmaceuticals in the WWTP effluent is one of the-end-of-pipe solutions that are considered most ready for full-scale use. However, there are several aspects o

Influence of Small Pilot on Main Injection in a Heavy-Duty Diesel Engine

Factors influencing the effect of pilot-injection on main-injection combustion were investigated using heat release analysis in a heavy-duty diesel engine fuelled with standard diesel fuel, and included the effect of those factors on engine performance and emissions.Combinations of pilot injection parameters i.e. pilot start of injection, pilot mass, pilot-main injection separation, and rail pressFactors influencing the effect of pilot-injection on main-injection combustion were investigated using heat release analysis in a heavy-duty diesel engine fuelled with standard diesel fuel, and included the effect of those factors on engine performance and emissions.Combinations of pilot injection parameters i.e. pilot start of injection, pilot mass, pilot-main injection separation, and rail press