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We have characterized the electronic structure of FeSe1−xTex for various x values using soft x-ray photoemission spectroscopy (SXPES), high-resolution photoemission spectroscopy (HRPES) and inverse photoemission spectroscopy (IPES). The SXPES valence band spectral shape shows that the 2 eV feature in FeSe, which was ascribed to the lower Hubbard band in previous theoretical studies, becomes less prominent with increasing x. HRPES exhibits systematic x dependence of the structure near the Fermi level (EF): its splitting near EF and filling of the pseudogap in FeSe. IPES shows two features, near EF and approximately 6 eV above EF; the former may be related to the Fe 3d states hybridized with chalcogenide p states, while the latter may consist of plane-wave-like and Se d components. In the incident electron energy dependence of IPES, the density of states near EF for FeSe and FeTe has the Fano lineshape characteristic of resonant behavior. These compounds exhibit different resonance profiles, which may reflect the differences in their electronic structures. By combining the PES and IPES data the on-site Coulomb energy was estimated at 3.5 eV for FeSe.  相似文献   
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We use the gradient of the energy-integrated angle resolved photoemission (ARPES) intensity in order to define precisely the Fermi surface (FS) in BSCCO superconductors. We show that, independent of the photon energy, the FS is a hole barrel centered at (, ). Then, the superconducting gap along the FS is precisely determined from ARPES measurements on overdoped and underdoped samples of Bi2212. As the doping decreases, the maximum gap increases, but the slope of the gap near the nodes decreases. Though consistent with d-wave symmetry, the gap with underdoping cannot be fit by the simple cos(k x) – cos(k y) form. A comparison of our ARPES results with available penetration depth data indicates that the renormalization of the linear T suppression of the superfluid density at low temperatures due to quasiparticle excitations around the d-wave nodes is large and doping dependent.  相似文献   
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How annealing influences the morphology of a highly regioregular poly(3‐hexylthiophene) (RR‐P3HT) film at the substrate interface as well as the lateral inhomogeneity in the electronic structure of the film are elucidated. Whereas previous studies have reported that high‐molecular‐weight (MW) RR‐P3HT films tend to show low crystallinity even after annealing, it is found that high‐MW RR‐P3HT does show high crystallinity after annealing at high temperature for a long time. Photoemission electron microscopy (PEEM), X‐ray photoemission spectroscopy, and ultraviolet photoemission spectroscopy results clearly resolve a considerable lateral inhomogeneity in the morphology of RR‐P3HT film, which results in a variation of the electronic structure depending on the local crystallinity. The PEEM results show how annealing facilitates crystal growth in a high‐MW RR‐P3HT film.  相似文献   
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The paper discusses SeamlessDesign, a novel collaborative workspace for rapid creation of 3D objects with constraints. Its seamless design supports both shape and behavioral designs of 3D objects in a unified and intuitive manner. Virtual and augmented setups support both multiple perspectives for parallel activity and face-to-face interaction for rich awareness  相似文献   
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Bubble formation from a single-hole nozzle placed vertically upward in a rotating water bath was investigated using a high-speed video camera. Air was used as the working gas. The measured values of the frequency of bubble formation, f B, were compared with those observed in a stationary bath, f B0. The velocity of cross-flow, νθ, affected the bubble formation significantly when it exceeded a critical value, νθc . The ratio of f B to f B0 was unity for νθ≦νθc , but it changed in a complex manner for νθθc . In the latter case, when the air flow rate Q g was relatively low, f B/f B0 became larger than unity irrespective of Q g, and an empirical correlation of f B/f B0 was proposed as a function of νθ and the inner diameter of the nozzle, d ni. As the gas flow rate increased, f B/f B0 decreased monotonically and became smaller than unity, and an empirical correlation of f B/f B0 was derived as a function of Q g, νθ, and d ni. These empirical correlations could approximate the measured values of f B/f B0 within a scatter of −15 to +20 pct.  相似文献   
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A pertinent electrochemical synthesis of 2,4,6-trichloroaniline (TCA) in anhydrous media was studied. The influence of the solvent, the chlorinating reagent, the electricity passed and the nature of the anode material, were investigated. TCA was produced in electrolytic solutions whose solvents were amides with strong nucleophilicity as N,N-dimethylformamide (DMF) and N,N-dimethylacetoamide (DMAc), and was obtained selectively by the controlled potential electrolysis of aniline in the solution containing LiCl. The definition of the experimental conditions corresponding to an optimum and selective electrolysis of TCA was described.  相似文献   
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