Epsilon iron as a spin-smectic state.

Using X-ray emission spectroscopy, we find appreciable local magnetic moments until 30 GPa to 40 GPa in the high-pressure phase of iron; however, no magnetic order is detected with neutron powder diffraction down to 1.8 K, contrary to previous predictions. Our first-principles calculations reveal a "spin-smectic" state lower in energy than previous results.

XRD and XAS structural study of CuAlO2 under high pressure.

We present the results of x-ray diffraction and x-ray absorption spectroscopy experiments in CuAlO(2) under high pressure. We discuss the polarization dependence of the x-ray absorption near-edge structure at the Cu K-edge. XRD under high pressure evidences anisotropic compression, the a-axis being more compressible than the c-axis.

CO2-helium and CO2-neon mixtures at high pressures.

The properties of mixtures of carbon dioxide with helium or neon have been investigated as a function of CO(2) concentration and pressure up to 30 GPa at room temperature. The binary phase diagrams of these mixtures are determined over the full range of CO(2) concentrations using visual observations and Raman scattering measurements. Both diagrams are of eutectic type, with a fluid-fluid miscibility gap for CO(2) concentrations in the range [5, 75] mol.

Iron under pressure: "Kohn tweezers" and remnant magnetism.

In this work we investigate the magnetic and structural properties of bulk Fe and Fe nanoparticles under pressure with x-ray absorption and emission spectroscopies providing answers to two fundamental questions: (a) the chicken-or-egg problem for the magnetic and structural transitions and (b) magnetism in the high pressure hcp phase. The two transitions, inextricably linked in the bulk, are clearly decoupled in the nanoparticles, with the magnetic collapse preceding the structural transition. Ultrafast x-ray emission spectroscopy detects remnant magnetism, probably antiferromagnetic fluctuations, up to pressures of about 40 GPa in the hcp phase.

Structure of carbon dioxide phase IV: breakdown of the intermediate bonding state scenario.

The existence of "intermediate bonding states" in solid CO2, separating the low-pressure molecular phases from the high-pressure polymeric forms, has been the matter of a long-standing debate. Here we determine the structure of CO2-IV using x-ray diffraction of single crystals grown inside a diamond anvil cell at 11.7 GPa and 830 K.

Liquid mercury sound velocity measurements under high pressure and high temperature by picosecond acoustics in a diamond anvils cell.

Recent improvements to measure ultrasonic sound velocities of liquids under extreme conditions are described. Principle and feasibility of picosecond acoustics in liquids embedded in a diamond anvils cell are given. To illustrate the capability of these advances in the sound velocity measurement technique, original high pressure and high temperature results on the sound velocity of liquid mercury up to 5 GPa and 575 K are given.

Pressure transmitting medium Daphne 7474 solidifying at 3.7 GPa at room temperature.

A pressure transmitting medium named Daphne 7474, which solidifies at P(s)=3.7 GPa at room temperature, is presented. The value of P(s) increases almost linearly with temperature up to 6.

Experimental and theoretical investigation on the relative stability of the PdS2- and pyrite-type structures of PdSe2.

Under ambient condition PdSe2 has the PdS2-type structure. The crystal structure of PdSe2 under pressure (up to 30 GPa) was investigated at room temperature by X-ray diffraction in an energy-dispersive configuration using a diamond anvil cell with a mixture of water/ethanol/methanol as a pressure transmitting medium. A reversible structural transition from the PdS2-type to the pyrite-type structure occurs around 10 GPa, and the applied pressure reduces the spacing between adjacent 2/proportional to [PdSe2] layers of the PdS2-type structure to form the three-dimensional lattice of the pyrite-type structure.

Pseudomonas costantinii sp. nov., another causal agent of brown blotch disease, isolated from cultivated mushroom sporophores in Finland.

Pathogenic bacteria are frequently associated with mushroom sporophores exhibiting brown blotch disease symptoms. These bacteria belong mainly to Pseudomonas tolaasii or occasionally to 'Pseudomonas reactans'. Although a group of isolates originating from some Finnish mushroom farms satisfied the two characteristic criteria for diagnosis of infection with P.

Several pseudomonads, associated with the cultivated mushrooms Agaricus bisporus or Pleurotus sp., are hemolytic.

Pseudomonas tolaasii, causing brown blotch disease on cultivated mushrooms, and yielding a white line precipitate towards P. "reactans", has been shown to induce lysis of erythrocytes. Some Finnish strains isolated from diseased mushroom fruit bodies, although harboring the typical features of P.

Evidence for genotypic differences between the two siderovars of Pseudomonas tolaasii, cause of brown blotch disease of the cultivated mushroom Agaricus bisporus.

Sixteen representative isolates of Pseudomonas tolaasii, the causal agent of brown blotch of the cultivated mushroom Agaricus bisporus, were previously assigned to two siderovars (sv1 and sv2) on the basis of pyoverdines synthesized. Each isolate was pathogenic and produced a typical white line precipitate when cultured adjacent to Pseudomonas "reactans" strain LMG 5329. These 16 isolates of P.

The white-line-in-agar test is not specific for the two cultivated mushroom associated pseudomonads, Pseudomonas tolaasii and Pseudomonas "reactans".

A sharply defined white line in vitro forms between the pathogenic form of Pseudomonas tolaasii and another Pseudomonas bacterium, referred to as "reactans". This interaction has been considered as highly specific. However, results presented in this study rise doubt about the strict specificity of this interaction, as some other pseudomonads, associated with the cultivated mushroom Agaricus bisporus, also yielded a white line precipitate when they were streaked towards Pseudomonas tolaasii LMG 2342T.

The structure of a pyoverdine produced by a Pseudomonas tolaasii-like isolate.

Cultures of Agaricus bisporus, the most extensively cultivated mushroom, can be infected severely by Pseudomonas tolaasii. This pathogen is characterized by the so-called white line reaction, a precipitate formed on agar plates between its colonies and those of P. reactans, both belonging to the collective species P.

Application of siderotyping for characterization of Pseudomonas tolaasii and "Pseudomonas reactans" isolates associated with brown blotch disease of cultivated mushrooms.

Pyoverdine isoelectric focusing analysis and pyoverdine-mediated iron uptake were used as siderotyping methods to analyze a collection of 57 northern and central European isolates of P. tolaasii and "P. reactans.