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Historians of natural history have shown that the study of plants, animals, and minerals was a form of connoisseurship in the eighteenth century. Historians of early modern experiments have linked scientific knowledge to the manual skills of artisans. I combine these two insights, arguing that connoisseurship in the sciences meant learning to touch, not just learning to look. The focus is on gems and mineralogy in eighteenth-century France. I show, firstly, that the study of gems was linked to the connoisseurship ("connoissance") of paintings. Next, books on gems were closely related to the new mineralogical treatises that emerged in the middle of the eighteenth century. These treatises formalized a distinction between "Oriental" and "Occidental" gems that was also a distinction between hard and soft gems. The best judges of hardness were gem cutters, a group that participated in mineralogy through the culture of collecting. Finally, the knowledge of cutters contributed to the quantification of hardness in the form of the hardness scale and the scratch sclerometer. [ABSTRACT FROM AUTHOR]

Leydetite, monoclinic Fe(UO2)(SO4)2(H2O)11(IMA 2012–065), is a new supergene uranyl sulfate from Mas d''Alary, Lodève, Hérault, France. It forms yellow to greenish, tabular, transparent to translucent crystals up to 2 mm in size. Crystals have a vitreous lustre. Leydetite has a perfect cleavage on (001). The streak is yellowish white. Mohs hardness is ∼2. The mineral does not fluoresce under long- or short-wavelength UV radiation. Leydetite is colourless in transmitted light, non-pleochroic, biaxial, with α = 1.513(2), γ = 1.522(2) (further optical properties could not be measured). The measured chemical composition of leydetite, FeO 9.28, MgO 0.37, Al2O30.26, CuO 0.14, UO340.19, SO321.91, SiO20.18, H2O 27.67, total 100 wt.%, leads to the empirical formula (based on 21 O a.p.f.u.), (Fe0.93Mg0.07Al0.04Cu0.01)Σ1.05(U1.01O2)(S1.96Si0.02)Σ1.98O8(H2O)11. Leydetite is monoclinic, space group C2/c, with a= 11.3203(3), b= 7.7293(2), c= 21.8145(8) Å, β = 102.402(3)°, V= 1864.18(10) Å3, Z= 4, and Dcalc= 2.55 g cm–3. The six strongest reflections in the X-ray powder diffraction pattern are [dobsin Å (I) (hkl)]: 10.625 (100) (002), 6.277 (1) (111), 5.321 (66) (004), 3.549 (5) (006), 2.663 (4) (008), 2.131 (2) (0 0 10). The crystal structure has been refined from single-crystal X-ray diffraction data to R1= 0.0224 for 5211 observed reflections with [I> 3σ(I)]. Leydetite possesses a sheet structure based upon the protasite anion topology. The sheet consists of UO7bipyramids, which share four of their equatorial vertices with SO4tetrahedra. Each SO4tetrahedron, in turn, shares two of its vertices with UO7bipyramids. The remaining unshared equatorial vertex of the bipyramid is occupied by H2O, which extends hydrogen bonds within the sheet to one of a free vertex of the SO4tetrahedron. Sheets are stacked perpendicular to the cdirection. In the interlayer, Fe2+ions and H2O groups link to the sheets on either side via a network of hydrogen bonds. Leydetite is isostructural with the synthetic compound Mg(UO2)(SO4)2(H2O)11. The name of the new mineral honours Jean Claude Leydet (born 1961), an amateur mineralogist from Brest (France), who discovered the new mineral. [ABSTRACT FROM AUTHOR]

Abstract: A new international-patent-pending (PCT/US2010/52887) detector type, named here as 3D-Trench electrode Si detectors, is proposed in this work. In this new 3D electrode configuration, one or both types of electrodes are etched as trenches deep into the Si (fully penetrating with SOI or supporting wafer, or non-fully penetrating into 50–90% of the thickness), instead of columns as in the conventional (“standard”) 3D electrode Si detectors. With trench etched electrodes, the electric field in the new 3D electrode detectors are well defined without low or zero field regions. Except near both surfaces of the detector, the electric field in the concentric type 3D-Trench electrode Si detectors is nearly radial with little or no angular dependence in the circular and hexangular (concentric-type) pixel cell geometries. In the case of parallel plate 3D trench pixels, the field is nearly linear (like the planar 2D electrode detectors), with simple and well-defined boundary conditions. Since each pixel cell in a 3D-Trench electrode detector is isolated from others by highly doped trenches, it is an electrically independent cell. Therefore, an alternative name “Independent Coaxial Detector Array”, or ICDA, is assigned to an array of 3D-Trench electrode detectors. The electric field in the detector can be reduced by a factor of nearly 10 with an optimal 3D-Trench configuration where the junction is on the surrounding trench side. The full depletion voltage in this optimal configuration can be up to 7 times less than that of a conventional 3D detector, and even a factor of two less than that of a 2D planar detector with a thickness the same as the electrode spacing in the 3D-Trench electrode detector. In the case of non-fully penetrating trench electrodes, the processing is true one-sided with backside being unprocessed. The charge loss due to the dead space associated with the trenches is insignificant as compared to that due to radiation-induced trapping in sLHC environment. Since the large electrode spacing (up to 500μm) can be realized in the 3D-Trench electrode detector due to their advantage of greatly reduced full depletion voltage, detectors with large pixel cells (therefore small dead volume) can be made for applications in photon science (e.g. X-ray). [Copyright &y& Elsevier]

Abstract: A replacement of the present CMS pixel detector with a better performing light weight four-layer system is foreseen in 2016. In the lifetime of this new system the LHC will reach and exceed its nominal luminosity of 1034 cm−2 s−1. Therefore the radiation hardness of all parts of the pixel system has to be reviewed. For the construction of the much larger four-layer pixel system, the replacement of the present double sided sensors by much cheaper single sided ones is considered. However, the construction of pixel modules with such sensors is challenging due to the small geometrical distance of the sensor high voltage and the ground of the readout electronics. This small distance limits the sensor bias to about 500V in the tested samples. [Copyright &y& Elsevier]

Abstract: Hadfield steel is well known for its high work hardening capacity and wear resistance. The alloy X120Mn12 is specifically used in railroad castings such as frogs and crossings in west European countries such as France. The influence of various contact parameters on the mechanical behaviour of this alloy was investigated by rolling contact tests. The results are described and discussed using micro-hardness measurements, optical and scanning electronic microscopy and EBSD analyses. [ABSTRACT FROM AUTHOR]

Abstract: Optical links are used for data transmission of the ATLAS inner detector in a radiation hazard environment at the Large Hadron Collider (LHC). The radiation tolerance is studied for the opto-electronics of GaAs VCSEL and epitaxial Si PIN with 30 and 70MeV protons at CYRIC. High speed Si and GaAs PIN photo-diodes are also investigated for upgrade to super-LHC. The annealing of GaAs VCSEL by charge injection is characterized. The GaAs devices show approximately linear degradations to fluence. The dependence on proton energy is compared to the Non-Ionizing Energy Loss calculations. [Copyright &y& Elsevier]