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191.
Takaaki Sakai Hiroshige Matsumoto Reiri Yamamoto Takao Kudo Sachio Okada Masato Watanabe Shin-ichi Hashimoto Hitoshi Takamura Tatsumi Ishihara 《Ionics》2009,15(6):665-670
An electrode design with no use of three-phase boundary was investigated using palladium electrode. The hydrogen evolution
rate of the palladium electrode cell using SrZr0.9Y0.1O3 − α
electrolyte followed Faraday’s law up to 180 mA cm−2, and the anode and cathode overpotentials were significantly lower than those of a platinum electrode cell, suggesting that
the palladium electrode is effective to improve the performance of the hydrogen-pumping cell using SrZrO3-based electrolyte. The rate-determining step (RDS) for electrode reaction was also investigated by changing the electrode
morphology and hydrogen partial pressure, and it was suggested that the RDS of the anode is a reaction at electrode/electrolyte
interface. 相似文献
192.
The plasma potential and its distribution play an important role in the highly-charged ion production and it is an important parameter of the electron cyclotron resonance (ECR) plasma. Emitting probes have been successfully used to determine plasma potential distributions in many plasma machines. In the framework of the ATOMKI-ECRIS plasma diagnostics research project, plasma-induced emitting probe was developed. It was proved that in certain conditions such probes could be reliably used without being damaged and without disturbing the plasma. Important observations were made related to the biased-disc effect. In favor of establishing the method of emitting probe usage in ECR plasma, dedicated experiments were performed at the NIRS-Kei2 all permanent compact ECR ion source. Based on the experiences gained after the NIRS experiments, the ATOMKI plasma-induced probe measurements could be interpreted. It was shown that biasing the Disc electrode negatively with respect to the source potential, the plasma potential measured on the resonant zone decreased, while the well-known ion beam current increase was obtained. This result proves the previous assumption [K.E. Stiebing, O. Hohn, S. Runkel, L. Schmidt, H. Schmidt-Böcking, V. Mironov, G. Shirkov, Phys. Rev. ST Accel. Beams 2 (1999) 123501], that the biased-disc changes the plasma potential distribution creating favorable conditions for ion beam extraction. 相似文献
193.
Yoong Ahm Kim Masashito Kojima Hiroyuki Muramatsu Daisuke Shimamoto Takuya Hayashi Morinobu Endo Mauricio Terrones Mildred S. Dresselhaus 《Journal of Raman spectroscopy : JRS》2008,39(9):1183-1188
We have carried out in situ Raman studies during the electrochemical insertion of lithium ions (Li+) into pristine and thermally treated multiwalled carbon nanotubes (MWNTs). We found an improved structural integrity as well as the removal of defects in the thermally treated tubes. The different Li+ insertion behaviors above 0.5 V in as‐grown and thermally treated tubes could be explained by the presence of defects on the outer surface of the tubes. No change of Raman spectra from 2.8 to 0.8 V is characterized by the coverage of Li+ on the outer surface of tubes, whereas the upshift of G band and the absence of a separated G band below 0.75 V indicate the formation of diluted graphite intercalation below the stage‐2 phase (LiC12). Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
194.
The purpose of this work is to study the potentialities of phase-shifting real-time holographic interferometry for the analysis of light-induced lens in photorefractive and nonlinear optical materials. We show that this technique can be used for quantitative evaluation of the phase distribution of a wavefront changed by a light-induced lens and, consequently, the refractive index changes in these materials. The basic principle of this technique combines real-time holographic interferometry with phase-shifting technique for interferogram analysis. This method is demonstrated with in situ visualization, monitoring and analysis in real-time and uses a Bi12SiO20 crystal as the holographic medium and a Bi12TiO20 as the test sample. 相似文献
195.
Love W Savinov V Mendez H Ge JY Miller DH Shipsey IP Xin B Adams GS Anderson M Cummings JP Danko I Hu D Moziak B Napolitano J He Q Insler J Muramatsu H Park CS Thorndike EH Yang F Artuso M Blusk S Khalil S Li J Mountain R Nisar S Randrianarivony K Sultana N Skwarnicki T Stone S Wang JC Zhang LM Bonvicini G Cinabro D Dubrovin M Lincoln A Naik P Rademacker J Asner DM Edwards KW Reed J Briere RA Ferguson T Tatishvili G Vogel H Watkins ME Rosner JL Alexander JP Cassel DG Duboscq JE Ehrlich R 《Physical review letters》2008,101(15):151802
We search for a non-SM-like CP-odd Higgs boson (a(1)(0)) decaying to tau(+)tau(-) or mu(+)mu(-) in radiative decays of the Upsilon(1S). No significant signal is found, and upper limits on the product branching ratios are set. Our tau(+)tau(-) results are almost 2 orders of magnitude more stringent than previous upper limits. Our data provide no evidence for a Higgs state with a mass of 214 MeV decaying to mu(+)mu(-), previously proposed as an explanation for 3 Sigma(+)-->pmu(+)mu(-) events observed by the HyperCP experiment. Our results constrain NMSSM models. 相似文献
196.
Bennett JV Mitchell RE Shepherd MR Besson D Pedlar TK Cronin-Hennessy D Gao KY Hietala J Kubota Y Klein T Lang BW Poling R Scott AW Zweber P Dobbs S Metreveli Z Seth KK Tan BJ Tomaradze A Libby J Martin L Powell A Wilkinson G Ecklund KM Love W Savinov V Mendez H Ge JY Miller DH Shipsey IP Xin B Adams GS Hu D Moziak B Napolitano J He Q Insler J Muramatsu H Park CS Thorndike EH Yang F Artuso M Blusk S Khalil S Li J Mountain R Nisar S Randrianarivony K Sultana N Skwarnicki T Stone S Wang JC 《Physical review letters》2008,101(15):151801
Using a total of 2.74 x 10(7) decays of the psi(2S) collected with the CLEO-c detector, we present a study of chi(cJ)-->gammaV, where V=rho(0), omega, phi. The transitions chi(c1)-->gammarho(0 and chi(c1)-->gammaomega are observed with B(chi(c1)-->gammarho(0))=(2.43+/-0.19+/-0.22) x 10(-4) and B(chi(c1)-->gammaomega)=(8.3+/-1.5+/-1.2) x 10(-5). In the chi(c1)-->gammarho(0) transition, the final state meson is dominantly longitudinally polarized. Upper limits on the branching fractions of other chi(cJ) states to light vector mesons are presented. 相似文献
197.
198.
We previously reported on the water soluble, optically active polymer, poly[N-(L)-(1-hydroxymethyl)propylmethacrylamide] (P(L-HMPMA)), which has lower critical solution temperatures of approximately 30 and 21 degrees C upon heating and cooling, respectively. The phase separation behavior of the P(L-HMPMA)-water binary system has a reversible and clear hysteresis during heating and cooling cycles. The present study describes the thermosensitive properties of the optically active polymer and its hydrogel. Circular dichroism and microcalorimetric measurements of the polymer in water supported the hypothesis that the soluble polymer chains might be compactly folded with an interaction between optically active side chains. In addition, these measurements showed the polymer chains in a state of relatively low hydration compared to that of P(D,L-HMPMA), which was free-radically synthesized from racemates of monomers. The solution properties reflected the swollen-shrunken behavior of corresponding hydrogels in response to temperature changes. The microscopic observation of aqueous polymer solutions and hydrogels also confirmed that the optically active properties of polymer chains affect their structure and thermosensitivity. SEM micrograph of the surfaces of the crosslinked P(L-HMPMA). 相似文献
199.
Muramatsu M Nagatani T 《Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics》1999,60(1):180-187
Soliton density wave is investigated numerically and analytically in the optimal velocity model (a car-following model) of a one-dimensional traffic flow with open boundaries. Soliton density wave is distinguished from the kink density wave. It is shown that the soliton density wave appears only at the threshold of occurrence of traffic jams. The Korteweg-de Vries (KdV) equation is derived from the optimal velocity model by the use of the nonlinear analysis. It is found that the traffic soliton appears only near the neutral stability line. The soliton solution is analytically obtained from the perturbed KdV equation. It is shown that the soliton solution obtained from the nonlinear analysis is consistent with that of the numerical simulation. 相似文献
200.
The resonance Raman profile of the Jahn-Teller coupled vibrations has been investigated in croconate ion, both experimentally and theoretically. A good qualitative agreement between theory and experiment is found for two non-totally symmetric vibrations which are taken into account in the theoretical calculation. 相似文献