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The crystal structure of YMgGa, yttrium magnesium gallide, is isotypic with LaMgGa and crystallizes in the hexagonal ZrNiAl type structure. It consists of a three-dimensional network of Mg and Ga atoms, in which Y atoms fill channels. There are two crystallographically independent Ga sites. One Ga atom (Ga1) has three Mg atoms as near neighbours and six Y atoms at a slightly longer distance, giving rise to a [3 + 6] coordination. Another Ga atom (Ga2) is also nine-coordinate but has six near Mg neighbours and three Y at a somewhat longer distance in a [6 + 3] coordination. The Mg atom is tetrahedrally coordinated by four Ga atoms and has two additional Mg neighbours at a slightly longer distance. The site symmetries for Y, Ga1, Ga2 and Mg are m2m, , 2m and m2m, respectively. The crystal used was an inversion twin.

A new compound, Mn3Pd20P6, has been synthesized and the crystal and magnetic structures have been determined by neutron powder diffraction. The crystal structure is cubic, with a = 11.9563(2) angstrom, space group Fm (3) over barm, and is isostructural to Mn3Ni20P6, a ternary ordering variant of the Cr23C6-type structure. The magnetic properties of Mn3Pd20P6 and Mn3Ni20P6 were studied by magnetization measurements. For Mn3Pd20P6 a transition, suggested to be of first order, to a ferromagnetic structure takes place at 110 K, whereas the saturation magnetization shows unusual temperature dependence. Magnetization vs. field loops show very weak coercivity, and the magnitude of the saturation magnetization agrees well with parallel Mn magnetic moments on two different sublattices of 4.24(8) mu(B), and 2.88(8) mu(B), respectively, found by neutron powder diffraction at 10 K. Magnetization vs. temperature measurements for Mn3Ni20P6 do not show a well-defined transition temperature, but show signatures of magnetic order with small excess magnetic moments aligned by the applied field below about 240 K. Further, signatures of a spin reorientation process at around 30 K are noted.

The effect of Cu substitution on the structural and magnetic properties of TbNi5-xCux (x=0,0.5,1.0,1.5,2.0) have been investigated by x-ray diffraction, magnetization measurements and neutron powder and single crystal diffraction. The electronic and the magnetic structures of TbNi5 were studied using first principles theory. All samples were found to have the CaCu5-type structure, space group P6/mmm. The lattice parameters increase monotonically with increasing Cu concentration. The Curie temperature T-c has a maximum value of 29 K at x=1.0. The magnetic structure of TbNi5 at 10 K is incommensurate with a helimagnetic component [wave vector q similar to 2 pi/c(0,0,0.02)] perpendicular to a ferromagnetic one. In contrast, the substituted TbNi5-xCux alloy is ferromagnetic. All magnetic moments are observed to be located on the Tb atoms. The magnetocrystalline anisotropy in the ab plane is observed to be strongly increased by the Cu substitution, whereas the magnetization decreases with the Cu concentration. The observed magnetic structure of TbNi5 is consistent with first principles calculations regarding both the magnetic moments and the helimagnetic structure. The microscopical origin of the helimagnet is analyzed and correlated to the Fermi surface topology.

We have recently proposed a new method to design one-dimensional structures of MgH2 in the nano- and micrometer ranges by hydrogen-induced disproportionation of bulk Mg24Y5. The present study confirms the same behavior in hydrogenated Mg5Ga2 and Mg6Pd. Single-crystalline one-dimensional structures and microparticles of MgH2 are formed by hydrogen absorption and subsequent partial disproportionation of Mg5Ga2 and Mg6Pd. The MgH2 whiskers and particles grow with different morphologies for different alloying partners. Growth mechanisms are proposed in relation to the morphology and the chemical surface composition of original compounds.

Remarkable formation of one-dimensional single crystalline MgH2 structures in the nano- and micro-meters ranges is reported. These structures have been tailored by hydrogen absorption and subsequent disproportionation of bulk Mg24Y5. The MgH2 whiskers have been structurally and morphologically characterized by X-rays diffraction, scanning and transmission electron microcopies. A growth model is proposed for the early stage of the whiskers formation by combining surface chemical and morphological investigations. The formation of MgH2 whiskers opens new engineering explorations and challenges for further experimental and theoretical studies.

Estimates on drinking water consumption are necessary in risk assessments on microbial hazardsin drinking water. Large differences in consumption habits between countries have beenreported. In order to establish estimates for the Swedish population, water consumption datafrom a waterborne outbreak investigation (157 people), a small water consumption study(75 people) and a large study on health and environmental factors (10,957 people) were analysed.A lognormal distribution for the daily direct/cold water intake in litres with m¼20.299 ands ¼ 0.570 was fitted to the quantitative data, representing the general population. The averagedaily consumption of tap water as plain drinking water and as heated tap water, e.g. in coffeeand tea, was 0.86 ^ 0.48 l and 0.94 ^ 0.69 l, respectively. Women consumed more cold tap waterthan did men, while men appeared to have a higher consumption of heated tap water. Cold tapwater intake was highest in the oldest age group, ($70 years). The consumption of bottled waterwas very low (mean 0.06 l/d) when compared to other countries.

A new compound, IrMnSi, has been synthesized, and its crystal structure and magnetic properties have been investigated by means of neutron powder diffraction, magnetization measurements, and first-principles theory. The crystal structure is found to be of the TiNiSi type (ordered Co2P, space group Pnma). The Mn-projected electronic states are situated at the Fermi level, giving rise to metallic binding, whereas a certain degree of covalent character is observed for the chemical bond between the Ir and Si atoms. A cycloidal, i.e., noncollinear, magnetic structure was observed below 460 K, with the propagation vector q=[0,0,0.4530(5)] at 10 K. The magnetism is dominated by large moments on the Mn sites, 3.8μB∕atom from neutron diffraction. First-principles theory reproduces the propagation vector of the experimental magnetic structure as well as the angles between the Mn moments. The calculations further result in a magnetic moment of 3.2μB for the Mn atoms, whereas the Ir and Si moments are negligible, in agreement with observations. A calculation that more directly incorporates electron-electron interactions improves the agreement between the theoretical and experimental magnetic moments. A band mechanism is suggested to explain the observed magnetic order.

A new compound, Mn8Pd15Si7, is reported to crystallize in a face centered cubic unit cell of dimension a = 12.0141(2) Å, space group, and can thus be classified as a G-phase. The crystal structure was studied by single crystal X-ray diffraction, X-ray and neutron powder diffraction and electron diffraction. A filled Mg6Cu16Si7 type structure was found, corresponding to the Sc11Ir4 type structure. The magnetic properties were investigated by magnetization measurements and Reverse Monte Carlo modeling of low temperature magnetic short-range order (SRO). Dominating near neighbor antiferromagnetic correlations were found between the Mn atoms and geometric frustration in combination with random magnetic interactions via metal sites with partial Mn occupancy were suggested to hinder formation of long-range magnetic order.

Two compounds, Mn3CoSi and Mn3CoGe have been synthesized and found to crystallize in the AlAu4 type structure, an ordered form of the β-Mn structure. The magnetic structure and properties have been studied by magnetometry and neutron powder diffraction and the theoretical work is based on first principles total energy calculations. Comparison is made with the magnetic properties of the isostructural compounds Mn3IrGe and Mn3IrSi. The solid solutions Mn3Ir1–yCoySi (0y1) and Mn3CoSi1–xGex (0x1) are also studied. A noncollinear antiferromagnetic structure is experimentally observed for y=0.20 as well as for x=0.50 and 1.0, similar to that of Mn3IrSi and Mn3IrGe, with 120° angles between magnetic moments on a triangular network of Mn atoms, and this finding is corroborated by theoretical calculations. For y=0.80–1.0 a transformation to a new type of magnetic structure takes place. The magnetic transition temperature decreases on decreasing unit cell dimension, with good qualitative agreement with the decay of the calculated interatomic exchange energy. Both theory and experiments find the magnitude of the Mn magnetic moment to decrease on decreasing unit cell volume, the same trend is found in calculations for β-Mn.

Wedged Mg–Y films with compositions ranging from pure Mg to Mg0.83Y0.17 were grown by dc-magnetron sputtering and hydrogenated. Mg1–xYx forms a substitutional alloy, ranging from 0 to at least 17 at. % in thin films. The c lattice parameter of the film containing 17 at. % of yttrium is determined to be approximatively 1% larger than in pure Mg. Upon exposure to 1 bar of hydrogen at 300 K, the samples switch from shiny metals to colorless semiconductor. Different characteristic hydrogen depth distributions are found for different Y concentrations. At low yttrium contents, a large concentration gradient is observed, with the highest hydrogen concentration close to the Pd/Mg1–xYx interface. For yttrium concentrations larger than 7 at. %, the obtained hydrogen distribution is almost independent of depth. The optical band gap is determined to be 3.6 eV, for all the Y concentrations. The optical transmission is found to decrease for increasing Y content, which is associated with an incomplete hydride formation in the films.

A new ternary phase, Mn4Ir7−xMnxGe6 (0x1.3), was studied by X-ray and neutron powder diffraction and SQUID magnetometry. The crystal structure is cubic, of the U4Re7Si6 type, space group , Z=2, with the lattice parameter at 295 K. Within the limited range of homogeneity small variations of the composition yield dramatic changes of the magnetic structure. For x=0 long-range antiferromagnetic order is formed below the transition temperature 228 K, with large magnetic moments on Mn, 4.11(9) μB at 10 K, in a magnetic unit cell , cM=2aC. In contrast, for x=1.3 spin glass behavior is observed below 90 K. The Mn atoms form an ideal cubic framework, on which geometric frustration of competing nearest and next nearest neighbor antiferromagnetic interactions is suggested to explain the composition sensitive magnetic properties. A TiNiSi-type phase, IrMnGe, is found in samples of 1:1:1 composition quenched from the melt.

A new ternary Ir-Mn-Si phase with stoichiometry Mn3IrSi has been synthesized and found to crystallize in the cubic AlAu4-type structure, space group P213 with Z=4, which is an ordered form of the β-Mn structure. The unit cell dimension was determined by x-ray powder diffraction to a=6.4973(3)Å. In addition to the crystal structure, we have determined the magnetic structure and properties using superconducting quantum interference device magnetometry and Rietveld refinements of neutron powder diffraction data. A complex noncollinear magnetic structure is found, with magnetic moments of 2.97(4)μB at 10 K only on the Mn atoms. The crystal structure consists of a triangular network built up by Mn atoms, on which the moments are rotated 120° around the triangle axes. The magnetic unit cell is the same as the crystallographic and carries no net magnetic moment. The Néel temperature was determined to be 210 K. A first-principles study, based on density functional theory in a general noncollinear formulation, reproduces the experimental results with good agreement. The observed magnetic structure is argued to be the result of frustration of antiferromagnetic couplings by the triangular geometry.

The Structural and magnetic propertiesof a new ternary Ir-Mn-Ge phase, Mn3IrGe, as well as the solid solution Mn3Ir(Si1_xGex), O

Pd3P, which crystallises in the cementite, Fe3C-type structure, forms a solid solution with nickel. The crystal structure contains two crystallographically different palladium sites (8d and 4c). Refinements of neutron powder diffraction intensities using the Rietveld method show that all nickel atoms occupy the eight-fold position. The unit cell parameters were refined to a=5.7812(4) Å, b=7.4756(6) Å and c=5.1376(4) Å, for Pd2.7Ni0.3P0.94.

Ti3Sn forms an orthorhombic metal hydride phase at 25-kPa deuterium pressure and 650 °C. The unit cell parameters were determined to be a=6.179(1) Å, b=9.877(2) Å and c=4.7898(6) Å and the space group to beC2221. The crystal structure was determined from neutron powder diffraction data with the Rietveld method. Three phases are formed in the Ti3Sn–D system upon hydrogenation, and appear in the following order at increasing deuterium pressures: an orthorhombic structure (Ti3SnD0.80), a hexagonal phase and a cubic metal hydride phase (Ti3SnD). The cubic phase, Ti3SnD, crystallises in the CaTiO3-type structure, space group Pm3m, with the unit cell parameter a=4.1776(2) Å. The stability of the three Ti3SnDx phases is in agreement with calculated total energies, based on first principles theory.

Two new ternary intermediate phases in the Pd-Ni-P system have been synthesized and the crystal structures have been determined by single-crystal X-ray diffraction. PdNi2P crystallizes in the MgCuAl2-type structure with the unit cell parameters a = 3.4708(3) Å, b = 8.4437(8) Å, c = 6.6083(5) Å, Z = 4, space group Cmcm. Pd8Ni31P16 is tetragonal with the unit cell parameters crystallographic non-equivalent positions This Hnes nnt crystallographic non-equivalent positions. This does not correspond to any previously reported structure.

The effect of the surface coating on the magnetic properties of superparamagnetic iron oxide nanoparticles (SPION) with 8 nm in size has been studied. Four different biocompatible coating layers are considered: poly L,L-lactic acid (PLLA), poly e-caprolactone (PCL), bovine serum albumin (BSA) and gold. The presence of coating layer on the surface of SPION is confirmed by FT-IR spectroscopy. Mössbauer spectroscopy and magnetic susceptibility measurements show that for uncoated SPION and Au@SPION the superparamagnetic fraction is retained. The formation of clusters in the case of BSA@SPION and chain-like structure for PCL@SPION and PLLA@SPION increase the inter-particle interactions resulting in hyperfine magnetic structure observed in the Mössbauer spectra at ambient temperature.

The hydrogen uptake and distribution in wedged Mg–Ni films, with composition ranging from Mg0.85Ni0.15 to Mg0.55Ni0.45, were investigated. Upon hydrogen loading at 298 K these films undergo a transition from a mirror-like metallic to a semiconducting transparent state. After exposure to a hydrogen pressure of 1 bar, the samples exhibit large variation in optical appearance, ranging from a pale yellowish (Mg rich side) to a brownish shade (Ni rich side). The change in the effective optical band gap Egeff as a function of sample composition and hydrogen concentration was determined; it showed changes from 3.6 eV in the Ni poor domain to 2.4 eV in the Ni rich domain. Composition analysis using the 15N nuclear resonance method showed close to homogeneous hydrogen distribution throughout the film and close to linear increase in the hydrogen uptake with increasing Mg content. The thermal stability of the films is limited; annealing above 393 K results in significant redistribution of the constituents. Mg is enriched at the surface, reacting with Pd and thereby degrading the capping layer through the formation of Mg6Pd and MgO, as determined by x-ray diffraction, x-ray photoelectron spectroscopy and Rutherford backscattering studies. This redistribution results in a severe decrease of the hydrogen uptake rate, as monitored by in situ resistivity measurements.

The present study investigated the prediction that the stereotype physical attractiveness produces automatic memory, this means automatic encoding and retrieval of stereotype congruent information. Furthermore, subjects' relationship between automatic memory and explicit prejudice was explored. Forty-seven subjects participated in a novel implicit memory test. After conceptual priming, they judged the valence of "face-trait word" pairs, in old and new stimuli. Reaction times and self-reported prejudice levels were recorded. Results confirmed automatic memory. However, participants failed to exhibit better automatic memory for stereotype congruent stimuli than for stereotype incongruent stimuli. Significant interactions showed that participants unintentionally retrieved positive and negative traits together with attractive faces faster. A positive trend was found between subjects' automatic memory for stereotype prejudice information and their explicit prejudice attitude. The findings support automaticity of memory.

Queer theory is a rather new branch of study, as it has only been named as an area since about 1991. But in Sweden it has also been rather influential, both in the scientific field and outside it; in the media, exemplified by the television serial Queer as folks, and in the political discourse. Nowadays politicians not only describes themselves as ‘feminists’ but also as ‘pro queerness’. Maybe queer is on its way to become a widely disseminated and even trendy term? But, when looking at the scientific field in Sweden, one recognise that the influents from queer theory is only visible in film- and theatre studies and, of course, in the area of gender studies. In media studies, on the other hand, queer and queer theory is still rather unknown. Therefor, what this paper is aiming to is, first, to investigate queer theory and, second, to estimate what the concept and the theory can do for media studies. The question is why it has been so widely adopted and why it might be important to consider it? And what, if something, might media studies, on the other hand, bring to queer theory?

This study tests the hypothesis that participants primed with intuition make stronger and quicker moral judgements, than participants primed with rationality. 68 students (51 female and 17 male) were primed and then asked to read stories describing morally questionable actions. Strength and time of moral judgement ratings were recorded, as well as self-reported rationality, experientiality (intuition) and disgust levels. There was no effect of priming on moral judgement. However, there was a significant main effect of experientiality. Participants high in experientiality made stronger moral judgements ( p < .006). There was also a significant interaction effect between rationality and disgust level, where participants low in rationality and high in disgust level made the strongest moral judgements (p < .001). Results are discussed in terms of Haidt's (2001) Social Intuitionist Model. Keywords: Moral judgement, intuition, priming, disgust.