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3D-macroporous chitosan-based scaffolds with in situ formed Pd and Pt nanoparticles for nitrophenol reduction

3D-macroporous chitosan-based scaffolds (cryogels) were produced via growth of metal-polymer coordinated complexes and electrostatic interactions between oppositely charged groups of chitosan and metal ions under subzero temperatures. A mechanism of reduction of noble metal complexes inside the cryogel walls by glutaraldehyde is proposed, which produces discrete and dispersed noble metal nanoparti

An insight into molecular motions and phase composition of gliadin/glutenin glycerol blends studied by 13C solid-state and 1H time-domain NMR

Monitoring of the molecular motions and secondary structures of gliadin (Gli) and glutenin (Glu) in blends with 10, 20, 30, and 40% glycerol was performed by solid-state (SS) and time domain (TD) NMR spectroscopy. Increasing the glycerol content increased the relative amount of β-sheets and disordered structures, while decreasing α-helices in Gli/Glu–glycerol blends studied by 13C CPMAS NMR. For ≥

Highly refractory Archaean peridotite cumulates : Petrology and geochemistry of the Seqi Ultramafic Complex, SW Greenland

This paper investigates the petrogenesis of the Seqi Ultramafic Complex, which covers a total area of approximately 0.5 km2. The ultramafic rocks are hosted by tonalitic orthogneiss of the ca. 3000 Ma Akia terrane with crosscutting granitoid sheets providing an absolute minimum age of 2978 ± 8 Ma for the Seqi Ultramafic Complex. The Seqi rocks represent a broad range of olivine-dominated plutonic

Urban sharing in smart cities : the cases of Berlin and London

Addressing urban sustainability challenges requires changes in the way systems of provision and services are designed, organised and delivered. In this context, two promising phenomena have gained interest from the academia, the public sector and the media: “smart cities” and “urban sharing”. Smart cities rely on the extensive use of information and communications technology (ICT) to increase effi

Faster Protocol for Endogenous Fatty Acid Esters of Hydroxy Fatty Acid (FAHFA) Measurements

Fatty acid esters of hydroxy fatty acids (FAHFAs) are a recently discovered class of endogenous lipids with antidiabetic and anti-inflammatory activities. Interest in these lipids is due to their unique biological activites and the observation that insulin-resistant people have lower palmitic acid esters of hydroxystearic acid (PAHSA) levels, suggesting that a FAHFA deficiency may contribute to me

A decision support framework for fatigue assessment of steel bridges

Many bridges are approaching or have already passed their expected service life. For steel bridges, fatigue is often the decisive degradation phenomenon that theoretically puts restrictions on a continued use. At the same time, fatigue is also afflicted with large uncertainties on the resistance side as well as on the action effect side. An accurate assessment of the service life will require meas

Media, Knowledge and Trust : The Deepening Epistemic Crisis of Democracy

The argument has two related parts: firstly, we are witnessing an “epistemic” crisis in public spheres that threatens to undermine political agency. This crisis has to do with the massive amounts and speed of information, the processes by which we construct knowledge, as well as the new forms of knowledge deriving from digital technologies. Many developments in information technologies benefit dem

Fast Laplace Transforms for the Exponential Radon Transform

The Fourier slice theorem for the standard Radon transform generalizes to a Laplace counterpart when considering the exponential Radon transform. We show how to use this fact in combination with algorithms for the unequally spaced fast Laplace transform to construct fast and accurate methods for computing both the forward exponential Radon transform and the corresponding back-projection operator.

The Great Ordovician Biodiversification Event (GOBE) : definition, concept and duration

The Ordovician biodiversification has been recognized since the 1960s; the term ‘The Great Ordovician Biodiversification Event’, abbreviated by many as the ‘GOBE’, has been used for the past 20 years. The conceptual development and terminology applied to this crucial episode in marine life signify its considerable complexity. The GOBE includes successive biodiversity phases of the pelagic and bent

Anchorless cooperative tracking using multipath channel information

Highly accurate location information is a key facilitator to stimulate future services for the commercial and public sectors. Positioning and tracking of absolute positions of wireless nodes usually requires information provided from technical infrastructure, e.g., satellites or fixed anchor nodes, whose maintenance is costly and whose limited operating coverage narrows the positioning service. In

Ultrahigh vacuum dc magnetron sputter-deposition of epitaxial Pd(111)/Al2O3(0001) thin films

Pd(111) thin films, ∼245 nm thick, are deposited on Al2O3(0001) substrates at ≈0.5Tm, where Tm is the Pd melting point, by ultrahigh vacuum dc magnetron sputtering of Pd target in pure Ar discharges. Auger electron spectra and low-energy electron diffraction patterns acquired in situ from the as-deposited samples reveal that the surfaces are compositionally pure 111-oriented Pd. Double-axis x-ray

Towards Nanowire Tandem Junction Solar Cells on Silicon

The development of photovoltaics as a serious means of producing renewable energy has accelerated greatly in the last ten years, with prices for silicon-based solar cell systems dropping dramatically in the last few years. The next great opportunity for photovoltaics following this competitiveness in prices will be to enhance the cell and panel efficiencies. It is quite generally seen that the mos

The Church of Yimrhane Kristos : An Archaeological Investigation

The purpose of this thesis is to augment our understanding of the Church of Yimrhane Kristos, and the Lasta period in which it was built, from the study of a variety of source materials. Due to the fact that the Lasta period suffers from the absence of adequate and reliable literary sources, this study largely depends on the elements of historic buildings as the basic data source. Using archaeomet