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991.
Atsushi Unemoto Yoshiki IwaiSatoshi Mitani Seung-Wook BaekSeitaro Ito Takaaki TomaiJunichi Kawamura Itaru Honma 《Solid State Ionics》2011,201(1):11-20
Lithium ion conducting solid-state composites consisting of lithium ion conducting ionic liquid, lithium bis(trifluoromethanesulfonyl)amide (Li-TFSA) dissolved 1-ethyl-3-methyl imidazolium bis(trifluoromethylsulfonyl)amide (EMI-TFSA), denoted by [yMLi+][EMI+][TFSA−] in this study, and various oxide particles such as SiO2, Al2O3, TiO2 (anatase and rutile) and 3YSZ are synthesized via a liquid route for the molar concentration of lithium, y, to be 1. The composite consists of SiO2 and the ionic liquid with y = 0.2 was also prepared. The ionic liquid are quasi-solidified at the above oxide particle surfaces when x is below 40 for y = 1 and x is below 30 for y = 0.2, corresponding to the confinable thickness of the ionic liquid at the oxides' surfaces to be approximately 5-10 nm regardless of the oxide compositions. The electrical conductivities of x vol.%[yMLi+][EMI+][TFSA-]-SiO2, Al2O3, TiO2s or 3YSZ composites are evaluated by ac impedance measurements. The quasi-solid-state composites exhibited liquid-like high apparent conductivity, e.g. 10− 3.3-10− 2.0 S cm− 1 in the temperature range of 323-538 K for SiO2-ionic liquid composites with y = 1. The self-diffusion coefficients of the constituent species of x vol.% [yMLi+][EMI+][TFSA−] (x is below 40, y = 0.2 and 1) − SiO2 are evaluated by the Pulse Gradient Spin Echo (PGSE)-NMR technique in the temperature range of 298-348 K. By the quasi-solidification of the ionic liquid at SiO2 particle surfaces, the absolute values of the diffusion coefficients of all constituent species decreased. The SiO2 surfaces work to promote ionization of ion pair, [EMI+][TFSA−], while significant influence on the solvation coordination, [Li(TFSA)n + 1]n−, was not observed. The apparent transport numbers of Li-containing species both in the bulk and the quasi-solidified ionic liquid showed similar values with each other, which was evaluated to be in the range of 0.010-0.017 for y = 0.2 and 0.051-0.093 for y = 1 in the abovementioned temperature range. 相似文献
992.
We propose the generation of entangled states with trapped calcium ions using a combination of an rf dressed state and a spin-dependent force. By using this method, a decoherence-free entangled state of rf qubits can be directly generated, and ideally its fidelity is close to unity. We demonstrate an rf entangled state with a fidelity of 0.68±0.08, which has a coherence time of more than 200 ms by virtue of the fact that it is an eigenstate with energy gaps between adjacent levels. Using the same technique, we also produce a qutrit-qutrit entangled state with a fidelity of 0.77±0.09, which exceeds the threshold value for separability of 2/3. 相似文献
993.
Acousto-electric force microscopy (AEFM), developed as a technique for high-resolution mapping of carrier characteristics in solids is described. This technique is based on an acousto-electric voltage (AEV) detection scheme where AEV pulses are obtained from the cantilever deflection caused by the electrostatic force acting between the cantilever tip and the sample surface. AEFM appears to be feasible, but an improved AEV detection scheme is required. 相似文献
994.
LU ZhongDao SA BenHao Masanori Matsuda Junichi Nagata Atsushi Nakamura Osamu Miyamura 《中国物理C(英文版)》2000,24(8):743-747
The Λ multiplicity and Λ/p ratio are studied by hadron transportation-string fragmentation model in relativistic heavy ion collisions. Firstly, the dependence of Λ multiplicity and Λ/p ratio on the system size and the collision centrality is studied. It shows that the Λ and p multiplicities go up as the increase of system size and the increase of collision centrality. However, their ratio keeps almost a constant. The effect of Λ annihilation cross section to Λ multiplicity and Λ/p ratio is also studied. It is found that this effect is weak: Λ multiplicity and Λ/p ratio have a little amount of increase by the decrease of Λ annihilation cross section. Even the cross section is down to zero, Λ/p ratio is only 1.2 in 200A GeV AuAu head on collision. The Λ/p ratio is obtained to be 0.28 in pp collision, lying in the range of experimental data:0.2—0.3. It is also obtained that the ratio in AA collisions is 3—5 times of that in pp collision. 相似文献
995.
We demonstrate an optical orthogonal frequency division multiplexing (OFDM) demultiplexer with an optical discrete Fourier transform circuit fabricated using silica planar lightwave circuit technology. This compact device can process an arbitrary number of subcarriers. The operation of a ten-channel device is demonstrated by demultiplexing a 100 Gbit/s (10 subcarrier × 10 Gbits/s) OFDM signal. We also discuss a main factor affecting characteristics degradation of the device. 相似文献
996.
997.
We investigate the dynamics of probability distributions of an initially one-mode coherent field interacting with a four-state molecular system, which is a single magnet with a tunneling across an anisotropic barrier, using a numerically exact approach. The population for each state, the phase properties of and
, and
), the entropy are calculated for a model system. The model predicts that the molecule and field become asymptotically disentangled at half of the revival time, and that optical Schrödinger-cat and magnetic Schrödinger-cat states are generated.This paper was originally presented at the 5th International Conference on NEAR FIELD OPTICS and RELATED TECHNOLOGIES (NFO-5), which was held on December 6–10, 1998 at Coganoi Bay Hotel, Shirahama, Japan, in cooperation with the Japan Society of Applied Physics and Mombusho Grant-in Aid for Scientific Research on Priority Areas “Near-field Nano-optics” Project, sponsored by Japan Society for the Promotion of Science. 相似文献
998.
Bernold Fiedler Atsushi Mochizuki Gen Kurosawa Daisuke Saito 《Journal of Dynamics and Differential Equations》2013,25(3):563-604
We consider systems of differential equations which model complex regulatory networks by a graph structure of dependencies. We show that the concepts of informative nodes (Mochizuki and Saito, J Theor Biol 266:323–335, 2010) and determining nodes (Foias and Temam, Math Comput 43:117–133, 1984) coincide with the notion of feedback vertex sets from graph theory. As a result we can determine the long-time dynamics of the entire network from observations on only a feedback vertex set. We also indicate how open loop control at a feedback vertex set, only, forces the remaining network to stably follow prescribed stable or unstable trajectories. We present three examples of biological networks which motivated this work: a specific gene regulatory network of ascidian cell differentiation (Imai et al., Science 312:1183–1187, 2006), a signal transduction network involving the epidermal growth factor in mammalian cells (Oda et al., Mol Syst Biol 1:1–17, 2005), and a mammalian gene regulatory network of circadian rhythms (Mirsky et al., Proc Natl Acad Sci USA 106:11107–11112, 2009). In each example the required observation set is much smaller than the entire network. For further details on biological aspects see the companion paper (Mochizuki et al., J Theor Biol, 2013, in press). The mathematical scope of our approach is not limited to biology. Therefore we also include many further examples to illustrate and discuss the broader mathematical aspects. 相似文献
999.
Atsushi Takeuchi 《随机分析与应用》2019,37(2):155-170
Consider real-valued processes determined by stochastic differential equations driven by Lévy processes. The jump parts of the driving Lévy process are not always α-stable ones, nor symmetric ones. In the present article, we shall study the pathwise uniqueness of the solutions to the stochastic differential equations under the conditions on the coefficients that the diffusion and the jump terms are Hölder continuous, while the drift one is monotonic. Our approach is based on Gronwall’s inequality. 相似文献
1000.
Atsushi Okamoto Hisashi Matsuoka Motoki Saito Yoshihisa Takayama Mototsugu Takamura 《Optical Review》1999,6(3):189-195
We propose a new optical network device photorefractive connection module (PRCM) which operates as optical switch, amplifier and signal distributor controlled by parallel optical signals. Simple optical control bus systems can be realized by cascade connection of PRCMs. PRCM branches off a desired channel from the spatial multiplexed optical bus line by appropriate setting of the control beam pattern. PRCM uses cross polarized four wave mixing (CPFWM) with extraordinary polarized writing beams and an ordinary polarized reading beam to achieve a high connection gain to the next PRCM stage. We analyze the phase matching angle of CPFWM in which the optical paths of two pump beams are slightly different. The phase conjugate reflectivity indicating a branching ratio of optical signal is derived and calculated in consideration of the phase mismatching Δk. The optimum pump ratio and the grating vector orientation for the largest phase conjugate reflectivity and signal amplification factor are discussed for optical design of PRCM. Since the measured signal beam power after passing through the BaTiO3 crystal is three or four times higher than its incident power, PRCM has a sufficient connection gain for optical bus and interconnection systems. 相似文献