Solving Elliptic Eigenproblems with Adaptive Multimesh hp-FEM

This paper proposes a novel adaptive higher-order nite element (hp-FEM) method for solving elliptic eigenvalue problems, where n eigenpairs are calculated simultaneously, but on individual higher-order nite element meshes. The meshes are automatically hp-rened independently of each other, with the goal to use an optimal mesh sequence for each eigenfunction. The method and the adaptive algorithm are described in detail. Numerical examples clearly demonstrate the superiority of the novel method over the standard approach where all eigenfunctions are approximated on the same nite element mesh

The source and the age of the soil organic matter of Anthrosols in SW Norway

Recent investigations showed that humus‑rich topsoil’s around the Baltic Sea have been formed by the application of pyrogenic organic matter (Acksel et al., 2016, Geoderma Reg. 7, 187–200) and organic materials (e.g. animal manure, organic waste) linked with human activity and, consequently, these soils were classified as Anthrosols (Acksel et al., 2017 (submitted)). Such humus‑rich topsoil’s, which were strongly influenced by anthropogenic activities and classified as plaggic Anthrosols, were described in SW Norway (Schnepel et al., 2014, J. Plant Nutr. Soil Sci., 177 (4), 638–645.). However, the source and the formation time of the Anthrosols in Norway have not been investigated in detail. Therefore, we characterized the soil organic matter composition by pyrolysis-field ionisation-mass spectrometry (Py-FIMS), benzene polycarboxylic acids (BPCA) determination, examined the source of the SOM by isotopic signatures (d34S) and estimated the age of the SOM by 14C AMS dating in order to find out the beginning of Anthrosol formation. Py-FIMS revealed high portions of sterols and fatty acids, indicating inputs of manure, similar to plaggic Anthrosols in NW Germany. The BC portions (≈ 19 % BC of Corg) were similar to various Anthrosols (≈ 25 % BC of Corg) and Chernozems (≈ 13 % BC of Corg) worldwide and indicated an input of combustion residues to soils by early fire events. The d34S isotope signature of the SOM ranged from 10 to 13.4 ‰ at the islands and 10.6 to 15.2 in the Jaeren region of SW Norway, corresponded to the Anthrosols in the Baltic Sea region (Median: d34S = 11.5 ‰) and indicated an input of marine biomass (d34S of seaweed = 20 ‰). All these results complemented the study of Schnepel et al. (2014) and provided strong evidence that these soils were formed by human activities. Ongoing analyses of 14C ages from these soils enable to estimate the timing of the soil formation and link it to settlement history

Nuclear and Non-Ionizing Energy-Loss for Coulomb Scattered Particles from Low Energy up to Relativistic Regime in Space Radiation Environment

In the space environment, instruments onboard of spacecrafts can be affected by displacement damage due to radiation. The differential scattering cross section for screened nucleus--nucleus interactions - i.e., including the effects due to screened Coulomb nuclear fields -, nuclear stopping powers and non-ionization energy losses are treated from about 50 keV/nucleon up to relativistic energies.Comment: Accepted for publication in the Proceedings of the ICATPP Conference on Cosmic Rays for Particle and Astroparticle Physics, Villa Olmo (Como, Italy), 7--8 October, 2010, to be published by World Scientifi

GEANT4 low energy electromagnetic models for electrons and photons

A set of physics processes has been developed in the Geant4 Simulation Toolkit to describe the electromagnetic interactions of photons and electrons with matter down to 250 eV. Preliminary comparisons of the models with experimental data show a satisfactory agreement

GEANT simulation of energy losses of slow hadrons

The algorithm of the simulation of energy losses for hadrons with kinetic energy down to few eV is described. The details of its implementation in Geant4 are discussed. The comparison of the results of simulation with the experimental data is presented

GIANO-TNG spectroscopy of red supergiants in the young star cluster RSGC2

The inner disk of the Galaxy has a number of young star clusters dominated by red supergiants that are heavily obscured by dust extinction and observable only at infrared wavelengths. These clusters are important tracers of the recent star formation and chemical enrichment history in the inner Galaxy. During the technical commissioning and as a first science verification of the GIANO spectrograph at the Telescopio Nazionale Galileo, we secured high-resolution (R~50,000) near-infrared spectra of three red supergiants in the young Scutum cluster RSGC2. Taking advantage of the full YJHK spectral coverage of GIANO in a single exposure, we were able to identify several tens of atomic and molecular lines suitable for chemical abundance determinations. By means of spectral synthesis and line equivalent width measurements, we obtained abundances of Fe and other iron-peak elements such as V, Cr, Ni, of alpha (O, Mg, Si, Ca and Ti) and other light elements (C, N, Na, Al, K, Sc), and of some s-process elements (Y, Sr). We found iron abundances between half and one third solar and solar-scaled [X/Fe] abundance patterns of iron-peak, alpha and most of the light elements, consistent with a thin-disk chemistry. We found a depletion of [C/Fe] and enhancement of [N/Fe], consistent with CN burning, and low 12C/13C abundance ratios (between 9 and 11), requiring extra-mixing processes in the stellar interiors during the post-main sequence evolution. Finally, we found a slight [Sr/Fe] enhancement and a slight [Y/Fe] depletion (by a factor of <=2), with respect to solar.Comment: Paper accepted on A&

A New Biocomposite Material Based on Wheat Waste and Suitable for 3D Printing Applications

Biopolymers, such as poly(lactic) acid (PLA), which is obtained through green synthesis pathways from renewable resources, has attracted considerable interest in recent years because of the increasing need to reduce petroleum-based plastic pollution and bringing their prices comparable with conventional thermoplastic commodities’ price (e.g., polyethylene, polypropylene, and polystyrene). The present work investigates the employment of 10%&nbsp;wt of natural materials, deriving from wheat milling process, as biofiller of PLA to develop a biocomposite filament suitable for 3D-printing technique. The inclusion of a cost-free natural material leads to a strong reduction of the whole material cost. Implementing this new class of composite material to additive manufacturing technique allows to dramatically reduce the environmental impact of 3D printed products