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M. Lavagnini F. Pfuner R. Monnier L. Degiorgi H.-M. Eiter L. Tassini B. Muschler R. Hackl J.-H. Chu N. Ru K.Y. Shin I.R. Fisher 《Physica B: Condensed Matter》2012,407(11):1864-1867
We summarize our recent efforts in investigating the charge–density-wave (CDW) state of the rare-earth tri-tellurides RTe3 by means of infrared and Raman techniques. We identify the CDW gap, as order parameter of the broken-symmetry ground state, as well as the collective mode of the CDW condensate. 相似文献
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In this work, a projection algorithm is considered for treating strongly continuous semigroups of demicontinuous pseudocontractions. Theorems of strong convergence of fixed points are established in the framework of real Hilbert spaces. 相似文献
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As stimulated Brillouin scattering (SBS) materials, solids have many advantages such as compactness, innoxiousness, and ease of handling. The SBS threshold and reflectivity of K8 glass, a solid material, are investigated. A SBS phase control experiment using K8 glass to achieve coherent beam combination is performed with a self-phase-control technique below the optical damage threshold. The experimental results show that the short-term phase has been stabilized well with λ/33.8 fluctuation during 256 shots (25.6 s), and that the long-term phase change with non-convective K8 glass is much slower than that with convective HT-70 liquid. 相似文献
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Catalytic Enantioselective CH Functionalization of Alcohols by Redox‐Triggered Carbonyl Addition: Borrowing Hydrogen,Returning Carbon 下载免费PDF全文
John M. Ketcham Inji Shin T. Patrick Montgomery Prof. Michael J. Krische 《Angewandte Chemie (International ed. in English)》2014,53(35):9142-9150
The use of alcohols and unsaturated reactants for the redox‐triggered generation of nucleophile–electrophile pairs represents a broad, new approach to carbonyl addition chemistry. Discrete redox manipulations that are often required for the generation of carbonyl electrophiles and premetalated carbon‐centered nucleophiles are thus avoided. Based on this concept, a broad, new family of enantioselective C? C coupling reactions that are catalyzed by iridium or ruthenium complexes have been developed, which are summarized in this Minireview. 相似文献
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The performance enhancement of 3D-printed electrode comprised of polylactic acid (PLA) and graphite (Gr) doped with graphene oxide (GO) was studied to detect five heavy metal ions in trace level. The pretreatment of PLA/Gr/GO electrode with potential cycling in H2SO4 solution achieved the most sensitive response. The characteristics of the composite electrodes were verified using XPS, FE-SEM, EDXS, Raman, and impedance spectroscopy. The experimental variables affecting the response current were optimized with respect to pH, deposition time, ratio of PLA/Gr/GO, and supporting electrolytes. The pretreated 3D-PLA/Gr/GO electrode showed a wide dynamic range from 0.5 ppb to 1.0 ppm with low detection limits of 0.039–0.13 ppb. The reliability of the PLA/Gr/GO electrode was evaluated by analyzing the reference samples of European Reference Materials. 相似文献
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Ryugo S. HAYANO Masaharu TSUBOKURA Makoto MIYAZAKI Hideo SATOU Katsumi SATO Shin MASAKI Yu SAKUMA 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2013,89(4):157-163
The Fukushima Dai-ichi NPP accident contaminated the soil of densely-populated regions in Fukushima Prefecture with radioactive cesium, which poses significant risks of internal and external exposure to the residents. If we apply the knowledge of post-Chernobyl accident studies, internal exposures in excess of a few mSv/y would be expected to be frequent in Fukushima.Extensive whole-body-counter surveys (n = 32,811) carried out at the Hirata Central Hospital between October, 2011 and November, 2012, however show that the internal exposure levels of residents are much lower than estimated. In particular, the first sampling-bias-free assessment of the internal exposure of children in the town of Miharu, Fukushima, shows that the 137Cs body burdens of all children (n = 1,383, ages 6–15, covering 95% of children enrolled in town-operated schools) were below the detection limit of 300 Bq/body in the fall of 2012. These results are not conclusive for the prefecture as a whole, but are consistent with results obtained from other municipalities in the prefecture, and with prefectural data. 相似文献