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The occurrence of the quartz‐carbonate alteration assemblage (listvenite) in ophiolites indicates that ultramafic rock represents an effective sink for dissolved CO2. However, the majority of earlier studies of ultramafic rock carbonation had to rely on the surface exposure of reaction textures and field relationships. Here we present the first observations on ultramafic rock alteration obtained from the 300 m deep BT1B drill hole, ICDP Oman Drilling Project, allowing for a continuous and high‐resolution investigation. Hole BT1B recovered continuous drill core intersecting surface alluvium, 200 m of altered ultramafic rock comprising mainly listvenite and minor serpentinite bands at 90 and 180 m depth, and 100 m of the underlying metamorphic sole. Textural evidence suggests that the carbonation of fully serpentinized harzburgite commenced by non‐equilibrium growth of spheroidal carbonate characterized by sectorial zoning resulting from radially oriented low‐angle boundaries. In the serpentinite, carbonate spheroids are composed of alternating magnesite cores and dolomite rims, whereas texturally similar carbonate in the listvenite is composed of Fe‐rich magnesite cores and Ca‐Fe‐rich magnesite rims. The distinct compositions and mineral inclusions indicate that the carbonation extent was controlled by fluid accessibility resulting in the simultaneous formation of limited carbonate in the serpentinite bands and complete carbonation in the listvenite parts of BT1B. The presence of euhedral magnesite overgrowing spheroidal carbonate in the listvenite suggests near‐equilibrium conditions during the final stage of carbonation. The carbonate clumped isotope thermometry constrains carbonate crystallization between 50 °C and 250 °C, implying repeated infiltration of reactive fluids during ophiolite uplift and cooling. Key Points: Large‐scale carbonation resulted in pervasive replacement of serpentinite by the magnesite‐quartz‐fuchsite (listvenite) assemblageClumped isotope thermometry indicates carbonation temperatures between 50 °C and 250 °CCarbonation textures indicate a transition from non‐equilibrium spheroidal growth to near‐equilibrium euhedral growth [ABSTRACT FROM AUTHOR]

The first European superconducting winding pack (WP) and the first set of coil cases [toroidal field coil cases (TFCC)] for ITER are going to be delivered in 2017. The TFCC are steel structures that provide structural integrity to the WP, contribute to neutron shielding capacity, provide support to operating forces, and offer interface connections with the rest of the ITER machine. The TFCC assembly is formed by four main parts: two sectors with U-shaped section and two closure plates, which, after being welded together, enclose the WP. Each TFCC weights about 150 t and presents a wall thickness from 60 to 120 mm. The presence of distortions when welding such thick structures is particularly problematic in these components, which require tight tolerances and include several interfaces with other parts of the machine. In order to compensate the distortions, extra material is present in the critical areas to allow postwelding machining. The amount of extra material has to be optimized to reduce machining time and therefore the cost of the manufacturing. Thus, the evaluation of the welding-caused distortions is essential in order to confirm the extra-material strategy. In this scenario, an experimental and simulation campaign has been set up to predict the deformation of the TFCC during welding. First, welding coupons were welded in representative configurations. Then, these data were used to build a preliminary finite element method (FEM) model tool, using ANSYS software, which was then benchmarked against a "blind test" coupon and three TFCC-like mock-ups of 1-m length. Finally, a full FEM model was constructed using the previous outputs and is currently under assessment to predict the deformation of the TFCC during the welding process. This paper presents the numerical and experimental activities carried out so far, being EnginSoft S.p.A. the developer of FEM models, SIMIC S.p.A. the responsible of welding processes and data acquisition, and Fusion for Energy the contractual and technical supervisor. [ABSTRACT FROM AUTHOR]

BL13-XALOC is currently the only macromolecular crystallography beamline at the 3 GeV ALBA synchrotron near Barcelona, Spain. The optics design is based on an in-vacuum undulator, a Si(111) channel-cut crystal monochromator and a pair of KB mirrors. It allows three main operation modes: a focused configuration, where both mirrors can focus the beam at the sample position to 52 µm × 5.5 µm FWHM (H × V); a defocused configuration that can match the size of the beam to the dimensions of the crystals or to focus the beam at the detector; and an unfocused configuration, where one or both mirrors are removed from the photon beam path. To achieve a uniform defocused beam, the slope errors of the mirrors were reduced down to 55 nrad RMS by employing a novel method that has been developed at the ALBA high-accuracy metrology laboratory. Thorough commissioning with X-ray beam and user operation has demonstrated an excellent energy and spatial stability of the beamline. The end-station includes a high-accuracy single-axis diffractometer, a removable mini-kappa stage, an automated sample-mounting robot and a photon-counting detector that allows shutterless operation. The positioning tables of the diffractometer and the detector are based on a novel and highly stable design. This equipment, together with the operation flexibility of the beamline, allows a large variety of types of crystals to be tackled, from medium-sized crystals with large unit-cell parameters to microcrystals. Several examples of data collections measured during beamline commissioning are described. The beamline started user operation on 18 July 2012.