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In this article, we scrutinize a policy area in which the Russian government has had to react to negative publicity in the last few years, namely, the doping scandal surrounding the 2014 Sochi Winter Olympics. This scandal uncovered important aspects of Russia’s vulnerability in the global sports milieu, yet so far, it has remained almost unnoticed in the literature on mega sports events in Russia. Our analysis is premised on the convergence of two types and techniques of control and regulation: anatomopolitics, which presupposes, in Michel Foucault’s interpretation of the term, measures of control over individual bodies, and biopolitics, which refers to policy practices that target and concern the entire population. Their conflation in the Russian context results in a controversial effect: it strengthens relations of hegemony yet also exposes the sovereign power to the regulations of global sports organizations.
The three-dimensional distribution of melt in partially molten synthetic samples compositionally corresponding to diopside (90 wt.%)–anorthite (10 wt.%) and doped with PbO, WO3, MoO3, or Cs2O to enhance contrast was studied by X-ray computed tomography (CT) with synchrotron radiation. The heavy elements were strongly concentrated in the melt and contributed to an increase of the X-ray linear attenuation coefficient (LAC) of it. PbO was found to be compatible with silicate melt (>20 wt.% in solution) and incompatible with diopside crystals. Other oxides WO3 (∼10 wt.%), MoO3 (∼5 wt.%) and Cs2O (< 5 wt.%) are also soluble only in the melt. Such doping is useful not only for LAC control in X-ray CT measurements, but also for systematic control of the structure (wetting properties, distribution and connectivity) of partial melt. This technique gives basic information for discussion of the 3D distribution of partial melt having different wetting properties. As PbO was most effective in visualization of the diopside–anorthite partially molten system, CT images of the PbO-bearing sample were used for further 3D investigation of distribution. A distribution of dihedral angles at solid-melt-solid triple junctions ranging from 22 to 55° was observed with the 3D data. This range in angle distribution was probably caused by anisotropy of crystals and the result supports the argument that there is some limitation in a theoretical framework of stereology which estimates the 3D structure based on 2D observations. Investigators have begun to apply X-ray CT to the study of the 3D distribution of partial melts in rocks using synchrotron radiation. Our study on the effect of doping is one approach for developing a technique to investigate 3D melt distribution.
Pb2+-doped (Sr1−xPbx)3Ti2O7 (SPT) ceramics were fabricated by a solid state reaction. The stability and lattice structure of Sr3Ti2O7 and Sr4Ti3O10 Ruddlesden–Popper (RP) phases were studied as a function of Pb2+ content and sintering atmosphere. X-ray diffraction indicates that SrO(SrTiO3)n RP phase formation is sensitive to the Sr:Ti ratio of the raw materials and is a complex circularly iterative process. When the PbO concentration is less than x = 0.03, pure Sr3Ti2O7 can be obtained. Sr4Ti3O10 was found to be the main phase in the SPT samples for x ≥ 0.075. Pb2+ stabilizes SrO(SrTiO3)n RP phases by substitution for Sr2+ which reduces the lattice stress of the RP phase. It was observed that SrO vaporization losses at high temperature can be compensated by the decomposition of the intermediate SrPbO3 phase at lower temperature.
(Ba0.5Sr0.5)(Co0.8Fe0.2)O3−δ (BSCF) is a promising material with mixed ionic and electronic conductivity which is considered for oxygen separation membranes. Selective improvement of material properties, e.g. oxygen diffusivity or suppression of secondary phase formation, can be achieved by B-site doping. This study is concerned with the formation of Co-oxide precipitates in undoped BSCF at typical homogenization temperatures of 1,000°C, which act as undesirable nucleation sites for other secondary phases in the application-relevant temperature range. Y-doping successfully suppresses Co-oxide formation, whereas only minor improvements are achieved by Sc-doping. To understand the reason for the different behavior of Y and Sc, the lattice sites of dopant cations in BSCF were experimentally determined in this work. Energy-dispersive X-ray spectroscopy in a transmission electron microscope was applied to locate dopant sites exploiting the atom location by channeling enhanced microanalysis technique. It is shown that Sc exclusively occupies B-cation sites, whereas Y is detected on A- and B-cation sites in Y-doped BSCF, although solely B-site doping was intended. A model is presented for the suppression of Co-oxide formation in Y-doped BSCF based on Y double-site occupancy.
Thin films of AlxGa1−xN (0.05 ≤ x ≤ 0.96) having smooth surfaces were deposited directly on both vicinal and on-axis 6H-SiC(0001) substrates. Cross-sectional TEM of Al0.13Ga0.87N revealed stacking faults near the SiC/Nitride alloy interface and numerous threading dislocations. EDX, AES and RBS were used to determine the compositions, which were paired with their respective CL near band-edge emission energies. A negative bowing parameter was determined. The CL emission energies were similar to the bandgap energies obtained by SE. FE-AES of the initial growth of Al0.2Ga0.8N revealed an aluminum rich layer near the interface. N-type (silicon) doping was achieved for AlxGa1−xN for 0.12 ≤ x ≤ 0.42. Al0.2Ga0.8N/GaN superlattices were fabricated with coherent interfaces. Additionally, HEMT structures using an AlN/GaN/AlN buffer structure were fabricated.
Bis(cyclopentadienyl)magnesium (MgCp2) is used commonly as a source for doping nitride materials with magnesium. Increased oxygen incorporation known to accompany the use of MgCp2 makes the purity of this precursor an important consideration in nitride CVD. Gas chromatography-mass spectroscopy (GCMS) methods have now been developed for the identification of volatile impurities in MgCp2. Diethylether, an oxygen containing organic compound (CH3CH2OCH2CH3), and additional organic impurities were found in the MgCp2 supplied by three manufacturers. Subsequent refinements in the synthetic processes by these companies have resulted in the availability of MgCp2 free of ether and other organic impurities as determined by GCMS.
Mg has been widely used as p-doping species despite its intrinsic difficulties. It is nowadays well established that during the growth process of Mg doped GaN, atomic H is generated from the decomposition of NH3 and Mg-H complexes are formed in the layer. This has been for instance shown by the occurrence of LO mode in IR absorption, and by the observation of the Mg-H local vibration modes. This H passivation limits the electrical activity of Mg, therefore an activation process is required to get full activation of the Mg atoms. In the present study, bismethylcyclopentadienyl magnesium [(MeCp)2Mg] was used as precursor. However, this precursor reacts in the gas phase with NH3 to produce tiny solid particles as evidenced by a very bright diffuse emission visible along the laser beam used for reflectometry measurements. This simplest obvious product would be [(MeCp)Mg(NH2)]m(m≥2). To limit this drawback, Ga and Mg precursor lines have been separated. With proper in situ heat treatment, doping densities up to 1.5×1018 cm−3 have been obtained. PL spectra of lightly Mg doped samples (1016 cm−3) are dominated by shallow donor-acceptor pairs whereas for higher doping densities ( 1018 cm−3), the luminescence is dominated by a broad band in the 2.7-2.9 eV range. GaN LEDs were fabricated from Si doped (n-type) and Mg-doped (p-type) GaN, these LEDs emit in the blue-UV range.
Eu3+-doped SmBa3B9O18 luminescent materials were synthesized by high temperature solid state reactions. The structure and photoluminescence properties of Sm(1−x)EuxBa3B9O18 (x = 0.2, 0.4, and 0.6) were investigated by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, and photoluminescence spectra. The results show that doping of Eu3+ ions does not change the structure of SmBa3B9O18. The luminescence is mainly the characteristic Eu3+ ion luminescence. No concentration quenching processes occur with the increment of Eu3+ concentration. The work implies that SmBa3B9O18 is a potential host material and europium-doped SmBa3B9O18 may find application in display and optical devices.
Nearly ten years ago, a research program concerning materials and technologies was defined to develop the very complex cryogenic target for obtaining the combustion of a deuterium-tritium mixture by inertial confinement fusion in the laser megajoule facility. The CEA target fabrication project includes research and development on various organic polymers and materials for the cryogenic laser megajoule target assembly as well as for other targets that can be useful for the fusion program (pre and post-ignition). Recent advances have been accomplished concerning the development of specific organic materials for the fabrication of targets components, including the synthesis of polymers for the laser megajoule microshells and metal-doped organic foams for the elaboration of doped-foam microshells or for the micromachining of components.
Methoxy polyethylene glycol–epoetin β (pegylated epoetin β, peg-epoetin β, Mircera®) is an erythropoiesis-stimulating agent that is synthesized by pegylating epoetin β. It is prohibited in racehorses and humans because it enhances their performance. It is detectable in human urine and plasma using the isoelectric focusing–double-blotting (IEF–DB) method that has been widely applied in human doping control laboratories to detect doping with recombinant erythropoietins (EPOs). Fifty micrograms of peg-epoetin β were administered intravenously to a 450 kg female Thoroughbred, and blood was collected for 48 h. The plasma was processed by immunopurification followed by IEF–DB. The analytical procedures required about 2 days. No peg-epoetin β was detected in the baseline plasma collected prior to drug administration. It was readily detected in samples collected at 2, 4, 6, 8, 24 and 48 h. The isoforms showed a characteristic pattern that differed from epoetin β and was unlike any other known erythrocyte-stimulating agent or recombinant EPO. No peg-epoetin β was detected in plasma from five control horses. The plasma samples were also tested by a rapid, automated and chemiluminescent immunometric assay for EPO (Immulite®). The samples collected from the treated horse at 2–48 h contained the equivalent of approximately 200–800 pg ml− 1 of peg-epoetin β. The samples from the ten control horses were negative. These data show that a small dose of peg-epoetin β is detectable for 48 h by two different methods that are based on two different principles (chemiluminescence immunoassay and IEF–DB). The Immulite® assay is suitable as a screen and the IEF–DB assay as a confirmation method. These studies need to be expanded to other horses. The screen and confirmation tests, if applied, will probably eliminate the use of peg-epoetin β as a horse doping agent.
Zinc oxide (ZnO) nanoparticles have been produced using precipitation
methods from ethanolic solution. Rare-earth metal doping was performed,
and the effect of lithium codoping on the luminescence properties of the
rare-earth doped products was assessed. The resulting particles were
characterized using cathodoluminescence and scanning electron microscopy.
It was found that lithium significantly enhanced the cathodoluminescence
signal from the rare-earth ions, which has been attributed to the
increased integration of the rare-earth ions into the ZnO structure. The
nanophase ZnO products were also annealed in argon, hydrogen, and oxygen,
with hydrogen being the most successful for removing the broad defect
emission present in as-grown samples and enhancing the ZnO near band edge
Based upon recent sales numbers, nutritional supplements play a key role in the lifestyle of a substantial proportion of the population. As well as products such as vitamins or minerals, several precursors of anabolic steroids are marketed as nutritional supplements. Another group of commercially available supplements are products for weight loss based upon herbal formulations originating from Ephedra species. Apart from supplements indicating the presence of these active compounds, numerous non-hormonal nutritional supplements were found that were contaminated with non-labelled anabolic steroids. Stimulating agents other than naturally occurring analogues of ephedrine were detected. A major group using dietary supplements are sportsmen, ranging from amateur level to elite athletes. Besides the possible health risks associated with the use of dietary supplements, athletes should take care not to violate the rules of the World Anti-Doping Agency because athletes remain responsible for substances detected in their biofluids, irrespective of their origin. Several analytical methods have been developed to determine the presence of doping agents as contaminants. The present review attempts to address the issues concerning the use of nutritional supplements and the detection of doping agents as contaminants in dietary supplements.
We discuss the application of ion microscopy and in situ electron
microscopy to the study of electronic and optical materials and devices.
We demonstrate how the combination of in situ transmission electron
microscopy and focused ion beam microscopy provides new avenues for the
study for such structures, enabling extension of these techniques to the
study of dopant distributions, nanoscale stresses, three-dimensional
structural and chemical reconstruction, and real-time evolution of defect
microstructure. We also discuss in situ applications of thermal,
mechanical, electrical, and optical stresses during transmission electron
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