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771.
We demonstrated a green all-fiber laser by splicing both ends of a Pr(3+)-doped ZBLAN fiber to silica fibers, whose ends were coated with a dielectric thin film. The output power and the slope efficiency were 322 mW and 53%, respectively, and the coupled pump power of the two blue GaN pump lasers in the silica fiber core was 652 mW. We estimated that the damage threshold of the spliced structure was at least 21 MW/cm2. This splicing technique should be applicable for other wavelengths and glass fibers having low melting temperatures. 相似文献
772.
Hideyuki Horisawa Shigeru Yamaguchi Ikkoh Funaki 《Applied Physics A: Materials Science & Processing》2011,104(3):935-940
Fundamental investigations of plasma diagnostics of a forward laser plasma acceleration employing laser–foil interactions
were conducted for an Al-foil target irradiated with an Nd:YAG laser of 1 J/pulse with pulse width of 10 ns. Temporal evolutions
of electron temperatures and densities were evaluated with electrostatic probes and spectroscopic diagnostics. From the results,
it was shown that an average speed of ions in a forward direction was about 40 km/s. Also, it was shown that the plasma temperature
and density were about 2.5–8 eV and 1010 cm−3, respectively. 相似文献
773.
Hideyuki Suzuki 《The European physical journal. Special topics》2014,223(12):2631-2635
In this paper, we consider a centralized strategy for scheduling charging patterns of electrical vehicles and other batteries in power grids. We formulate it as a load balancing problem with constraints, which tries to distribute the charging loads both spatially and temporally. We show that a variant of herding system can be applied to load balancing. 相似文献
774.
Hideyuki Yoshizawa Takashi Mihara Naoyuki Koide Corresponding author 《Liquid crystals》2013,40(1):143-149
We have synthesized liquid crystalline polymers containing an imidazolium salt moiety and a mesogenic group by the in situ photopolymerization of a liquid crystalline vinylimidazole monomer in order to investigate the relationship between their thermal properties and ionic conductivity. A smectic phase was shown by the vinylimidazole monomer. The in situ photopolymerization of the monomer was carried out in the temperature range of the smectic phase. The polymer thus prepared displayed a highly ordered smectic phase in the temperature range between room temperature and about 200°C. The ionic conductivity of the polymer increased with increasing temperature. Anisotropic ionic conductivity behavior was observed for the polymer. The ionic conductivity of the polymer aligned homogeneously is larger than when homeotropically aligned. 相似文献
775.
Rui Tamura Hiroki Takahashi Hideyuki Miura Zsolt Lepp Yoshitaka Nakajima Ken Hirotsu 《Supramolecular chemistry》2013,25(1):71-78
Abstract The crystal structures of (±)-[2-[4-(3-ethoxy-2-hydroxypropoxy)phenylcarbamoyl]ethyl] trimethylammonium p-chlorobenzenesulfonate [(±)-NCMe3] and its terminal methoxy derivative, (±)-NCMe3-OMe, are compared. The former racemate exhibited the phenomenon of Preferential Enrichment, whereas the latter failed to do so. Crystal data, (±)-NCMe3: CuKα radiation, space group P 1, Z = 2, a = 9.848(5), b = 14.823(3), c = 9.147(1) Å, α = 97.81(1), β = 92.68(3), γ = 105.92(2)°, D calc = 1.355 g/cm3, R = 0.056 for 3213 observed reflections; (±)-NCMe3-OMe: CuKα radiation, space group P 1, Z = 2, a = 11.350(1), b = 14.568(2), c = 8.2981(4) Å, α = 94.346(7), β = 112.376(5), γ = 78.622(9)°, D calc = 1.343 g/cm3, R = 0.069 for 1519 observed reflections. 相似文献
776.
A new parameter estimation method for nonlinear systems from time series data is proposed. For the purpose of unbiased estimation, we employ the idea of bootstrap method on regression problems. Our method can be applied into even short and noisy data and is expected to give us a robust estimation. Some benchmarks of estimating chaotic models show its practical applicability. We also try to apply this method to analysis for intermittent hormonal therapy for prostate cancer by using a mathematical model and real clinical data. 相似文献
777.
Morohashi I Sakamoto T Sotobayashi H Kawanishi T Hosako I Tsuchiya M 《Optics letters》2008,33(11):1192-1194
By combining a Mach-Zehnder-modulator-based flat comb generator (MZ-FCG) with a dispersion-flattened dispersion-decreasing fiber, femtosecond pulses have been generated from a cw light. Near-Fourier-transform-limit picosecond pulses generated from the MZ-FCG were compressed into femtosecond order by pulse compression. Our system enables flexible tuning of the repetition rate and pulse width, because those depend on the driving signal of the MZ-FCG. Pulse trains of 200 fs width were continuously and stably generated without mode hopping, with a repetition rate range from 5 to 17 GHz. Our system consists of a modulator and compression fiber; thus, the configuration is simpler and more stable. 相似文献
778.
779.
Takuma Watabe Prof. Hideyuki Otsuka 《Angewandte Chemie (International ed. in English)》2023,62(9):e202216469
We report a novel and versatile approach to achieving swelling-induced mechanochemistry using a multinetwork (MN) strategy that enables polymer networks to repeatedly swell with monomers and solvents. The isotropic expansion of the first network (FN) provides sufficient force to drive the mechanochemical scission of a radical-based mechanophore, difluorenylsuccinonitrile (DFSN). Although prompt recombination generally occurs in such highly mobile environments, the resulting pink radicals are kinetically stabilized in the gels, probably due to limited diffusion in the extended polymer chains. Moreover, the DFSN embedded in the isotropically strained chain exhibits increased thermal reactivity, which can be reasonably explained by an entropic contribution of the FN to the dissociation. The utility of the MN polymers is demonstrated not only in terms of swelling-force-induced network modification, but also in the context of tunable reactivity of the dissociative unit through proper design of the hierarchical network architecture. 相似文献
780.