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Valgarður : a database of the petrophysical, mineralogical, and chemical properties of Icelandic rocks

The Valgarður database is a compilation of data describing the physical and geochemical properties of Icelandic rocks. The dataset comprises 1166 samples obtained from fossil and active geothermal systems as well as from relatively fresh volcanic rocks erupted in subaerial or subaqueous environments. The database includes petrophysical properties (connected and total porosity, grain density, perme

Guldgubbar's changing ontology : Scandinavian Late Iron Age gold foil figures through the lens of intra-action

This chapter discusses minuscule gold foil figures from the Scandinavian Late Iron Age anddemonstrates how the figures are continuously in the making, rather than being still representations of gods. In the past, the figures’ affectual qualities, such as their small size, their shininess and their human-like and foldable character, invited play and experimentation, stressing the figures’ ongoingne

Klimatpolitiska rådets rapport 2023

Stigande halter av växthusgaser i atmosfären har rubbat balansen i jordens klimatsystem vilket har medfört en snabbt stigande global medeltemperatur. Den globala uppvärmningen ligger nu på drygt 1,1 grader jämfört med förindustriell tid. Utöver högre temperaturer har detta lett till fler extrema väderhändelser, smältande isar och stigande havsnivåer. De ekologiska, ekonomiska och sociala effektern

Linear and nonlinear optical properties of metallic nanocrystals in sapphire

In this paper we report the linear and non-linear optical properties of metallic nano-clusters in α-Al 2O 3 fabricated by ion implantation (from 2 to 8×10 16 ions/cm 2). Thereafter, the samples were annealed at temperatures from 600 to 1100°C in oxidising, reducing atmospheres. Once spherical nano-particles were synthesized, the samples were further irradiated with Si +++ with different energies a

Size characterisation of noble-metal nano-crystals formed in sapphire by ion irradiation and subsequent thermal annealing

Metallic nano-particles embedded in transparent dielectrics are very important for new technological applications because of their unique optical properties. These properties depend strongly on the size and shape of the nano-particles. In order to achieve the synthesis of metallic nano-particles it has been used the technique of ion implantation. This is a very common technique because it allows

Size-and shape-dependent nonlinear optical response of au nanoparticles embedded in sapphire

Nonlinear optical response of Au metallic nanoparticles, synthesized and embedded in sapphire by using ion implantation, as a function of their size and shape is studied. The size of the Au NPs was varied by controlling the annealing time of the gold-irradiated sapphire in a reducing atmosphere. Their shape was changed from approximately spherical to prolate by swift heavy-ion irradiation using Si

Composition dependent thermal annealing behaviour of ion tracks in apatite

Natural apatite samples with different F/Cl content from a variety of geological locations (Durango, Mexico; Mud Tank, Australia; and Snarum, Norway) were irradiated with swift heavy ions to simulate fission tracks. The annealing kinetics of the resulting ion tracks was investigated using synchrotron-based small-angle X-ray scattering (SAXS) combined with ex situ annealing. The activation energies

Orientation dependence of swift heavy ion track formation in potassium titanyl phosphate

Potassium titanyl phosphate crystals in both x-cut and z-cut were irradiated with 185 MeV Au ions. The morphology of the resulting ion tracks was investigated using small angle x-ray scattering (SAXS), transmission electron microscopy (TEM), and atomic force microscopy (AFM). SAXS measurements indicate the presence of cylindrical ion tracks with abrupt boundaries and a density contrast of 1 ± 0.5%

Composition and orientation dependent annealing of ion tracks in apatite - Implications for fission track thermochronology

The annealing behaviour of swift heavy-ion tracks in apatite from different origins is studied as a function of their crystallographic orientation and the mineral composition. The tracks were generated by irradiating the apatite samples with 2.3 GeV Bi ions, which have a comparable rate of energy loss to fission tracks in this mineral. The track radius was investigated using synchrotron-based smal

Morphology of ion irradiation induced nano-porous structures in Ge and Si1−xGex alloys

Crystalline Ge and Si1−xGex alloys (x = 0.83, 0.77) of (100) orientation were implanted with 140 keV Ge− ions at fluences between 5 × 1015 to 3 × 1017 ions/cm2, and at temperatures between 23 °C and 200 °C. The energy deposition of the ions leads to the formation of porous structures consisting of columnar pores separated by narrow sidewalls. Their sizes were characterized with transmission electr

Effect of annealing high-dose heavy-ion irradiated high-temperature superconductor wires

Heavy-ion irradiation of high-temperature superconducting thin films has long been known to generate damage tracks of amorphized material that are of close-to-ideal dimension to effectively contribute to pinning of magnetic flux lines and thereby enhance the in-field critical current. At the same time, though, the presence of these tracks reduces the superconducting volume fraction available to tr

Elongation of metallic nanoparticles at the interface of silicon dioxide and silicon nitride

In the process of shape transformation of metal nanoparticles (MNPs) embedded in dielectrics resulting from swift heavy-ion irradiation, key parameters such as the energy deposition threshold, the necessity of a molten track and the NP size have been identified for amorphous silicon dioxide. The extension of such parameters to other dielectrics is yet unclear. We present experimental evidence of t

Nanoscale density variations induced by high energy heavy ions in amorphous silicon nitride and silicon dioxide

The cylindrical nanoscale density variations resulting from the interaction of 185 MeV and 2.2 GeV Au ions with 1.0 μm thick amorphous SiNx:H and SiOx:H layers are determined using small angle x-ray scattering measurements. The resulting density profiles resembles an under-dense core surrounded by an over-dense shell with a smooth transition between the two regions, consistent with molecular-dynam

Vaporlike phase of amorphous Si O2 is not a prerequisite for the core/shell ion tracks or ion shaping

When a swift heavy ion (SHI) penetrates amorphous SiO2, a core/shell (C/S) ion track is formed, which consists of a lower-density core and a higher-density shell. According to the conventional inelastic thermal spike (iTS) model represented by a pair of coupled heat equations, the C/S tracks are believed to form via "vaporization" and melting of the SiO2 induced by SHI (V-M model). However, the mo

Structure, morphology and annealing behavior of ion tracks in polycarbonate

Ion tracks created in polycarbonate foils by irradiation with 2.2 GeV Au ions were characterized using a combination of small-angle x-ray and neutron scattering (SAXS/SANS) and Fourier transform infrared spectroscopy (FTIR). The ion tracks were found to consist of a cylindrical damage core with a radius of ∼2.5 ± 0.2 nm and a relative density approximately 5% below that of the pristine polycarbona

Intensified role of the European Union? : European Research Infrastructure Consortium as a legal framework for contemporary multinational research collaboration

This chapter gives an introduction to the European Research Infrastructure Consortium (ERIC) – a European Union (EU) policy tool introduced in 2009 with the purpose to set up and operate collaborative Research Infrastructures by granting them a legal personality and qualities of an international organization. The shared responsibility between the member states and the EU in the research and innova

Conical etched ion tracks in SiO2 characterised by small angle X-ray scattering

We present a systematic study of the evolution of chemically etched ion tracks formed in thermally grown a-SiO2 after irradiation with 1.1 GeV and 185 MeV Au ions. The irradiated material was subsequently etched with 2.5% hydrofluoric acid (HF) for different times yielding hollow conical shaped structures of various sizes. The characterisation of these structures was carried out by synchrotron-bas

“You have to live with some risk, it’s part of the profession”. Specialist ambulance nurses’ perceptions of assignments involving ongoing lethal violence

BackgroundAs a result of several violent terrorist incidents, authorities in Sweden have shifted from previous approaches of being certain that it is safe for the ambulance service to enter the scene, to a one where “safe enough” is sufficient, potentially making it possible to save more lives. The aim was therefore to describe specialist ambulance nurses' perceptions of the new approach to assign