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81.
Zegers RG Abend H Akimune H van den Berg AM Fujimura H Fujita H Fujita Y Fujiwara M Galès S Hara K Harakeh MN Ishikawa T Kawabata T Kawase K Mibe T Nakanishi K Nakayama S Toyokawa H Uchida M Yamagata T Yamasaki K Yosoi M 《Physical review letters》2003,90(20):202501
The excitation and subsequent proton decay of the isovector spin-flip giant monopole resonance (IVSGMR) is studied via the 208Pb(3He,t) reaction at 410 MeV. In the inclusive spectrum (60+/-5)% of the non-energy-weighted sum-rule strength for this 2 variant Planck's over 2h omega resonance was found in the region 29相似文献
82.
Suzuki M Waraksa CC Nakayama H Hanabusa K Kimura M Shirai H 《Chemical communications (Cambridge, England)》2001,(19):2012-2013
L-Lysine derivatives of viologens form supramolecular assemblies of fibers and ribbons in some aromatic solvents, and the charge separation reaction in these self-assembling systems proceeds with a similar efficiency to the MV2+ system. 相似文献
83.
Takeshi Yabuta Kanji Tsuru Satoshi Hayakawa Chikara Ohtsuki Akiyoshi Osaka 《Journal of Sol-Gel Science and Technology》2000,19(1-3):745-748
Bioactive organic-inorganic hybrids were synthesized through sol-gel processing starting from -methacryloxypropyltrimethoxysilane. NMR-spectroscopic studies showed the presence of silanol groups (Si–OH) and Si–O–Si bonds. In vitro tests of the hybrids for bioactivity with a simulated body fluid (Kokubo solution) indicated that only calcium-containing hybrids could form apatite on their surfaces. Thus the presence of calcium ions was no less important to deposit apatite than the formation of silanol groups or Si–O–Si bonds. 相似文献
84.
M. Andachi T. Nakayama M. Kawasaki S. Kurokawa H.-P. Loock 《Applied physics. B, Lasers and optics》2007,88(1):131-135
Visible and near-infrared laser light pulses were coupled into two different types of optical fiber cavities. One cavity consisted
of a short strand of fiber waveguide that contained two identical fiber Bragg gratings. Another cavity was made using a loop
of optical fiber. In either cavity ∼40 ps laser pulses, which were generated using a custom-built gain-switched diode laser,
circulated for a large number of round trips. The optical loss of either cavity was determined from the ring-down times. Cavity
ring-down spectroscopy was performed on 200 pL volumes of liquid samples that were injected into the cavities using a 100 μm
gap in the fiber loop. A detection limit of 20 ppm of methylene blue dye in aqueous solution, corresponding to a minimum absorptivity
of εC<6 cm-1, was realized.
PACS 42.62.Fi; 42.81.-i 相似文献
85.
M.-W. Chu Y. Shingaya T. Nakayama 《Applied Physics A: Materials Science & Processing》2007,86(1):101-106
A combined transmission electron microscopy (TEM) and Raman spectroscopy study has been performed on nanocrystalline Ba0.9Sr0.1TiO3 (BST) crystals and tubes. TEM investigations revealed the existence of 90 deg ferroelastic twins in the materials. Raman spectra showed an obvious shoulder (∼750 cm-1) from the broad band at ∼720 cm-1 that nominally represents the quasimode of E(LO4) and A1(LO3). The intensity of this shoulder increases with the twin population in the nanocrystalline materials, suggesting a correlation between the lattice dynamical characteristics and the long-range ferroelastic strain of the twin wall. The ferroelastic strain is mainly constrained along the c-axis of the BST unit cell, and the effect of this constraint is more pronounced in nanocrystalline materials than in bulks due to a significant wall volume ratio in twinned nano-materials. A1 phonons showing collective ion dynamics along the c-direction could be then hardened by the strain, while E symmetry exhibiting vibrations perpendicular to the c-axis would be less affected. The theoretically predicted giant LO–TO coupling in tetragonal ferroelectric perovskites [18] suggests that the hardening of the softest A1(TO1) mode in A1 symmetry is accompanied by that of the hardest A1(LO3) phonon. Consequently, the shoulder could be ascribed to the ferroelastic strain induced hardening of the quasimode with a considerable contribution from the A1(LO3) phonon. PACS 61.72.Ff; 63.22.+m; 77.80.Bh; 77.80.Dj 相似文献
86.
87.
Antiviral activity of natural occurring flavonoids in vitro 总被引:2,自引:0,他引:2
Y Tsuchiya M Shimizu Y Hiyama K Itoh Y Hashimoto M Nakayama T Horie N Morita 《Chemical & pharmaceutical bulletin》1985,33(9):3881-3886
88.
We have investigated the nonradiative deactivation process of malachite green in the singlet excited states, S(1) and S(2), by high-level ab initio quantum chemical calculations using the CASPT2//CASCF approach. The deactivation pathways connecting the Franck-Condon region and conical intersection regions are identified. The initial population in the S(1) state is on a flat surface and the relaxation involves a rotation of phenyl rings, which leads the molecule to reach the conical intersection between the S(1) and S(0) states, where it efficiently decays back to the ground state. There exists a small barrier connecting the Franck-Condon and conical intersection regions on the S(1) potential energy surface. The decay mechanism from the S(2) state also involves the twisting motion of phenyl rings. In contrast to the excitation to the S(1) state, the initial population is on a downhill ramp potential and the barrierless relaxation through the rotation of substituted phenyl rings is expected. During the course of relaxation, the molecule switches to the S(1) state at the conical intersection between S(2) and S(1), and then it decays back to the ground state through the intersection between S(1) and S(0). In relaxation from both S(1) and S(2), large distortion of phenyl rings is required for the ultrafast nonradiative decay to the ground state. 相似文献
89.
H. Akimune T. Yamagata S. Nakayama M. Fujiwara K. Fushimi K. Hara K. Y. Hara K. Ichihara K. Kawase K. Matsui K. Nakanishi A. Shiokawa M. Tanaka H. Utsunomiya M. Yosoi 《Physics of Atomic Nuclei》2004,67(9):1721-1725
Trinucleon molecular structures in 6He and 6Be were investigated by using the 6Li(7Li, 7Be)6He reaction at 455 MeV and 6Li(3He, t)6Be reaction at 450 MeV, respectively. Binary decays into t + t from a broad state at E x =18.0±1.0 MeV in 6He and into 3He + 3He from one at E x =18.0±1.2 MeV in 6Be, respectively, were observed by measuring trinucleon cluster decays in coincidence with reaction particles. The branching ratios for binary decay were estimated to be about 0.7 for 6He and 6Be. These large branching ratios show that a trinucleon cluster state exists as an isobaric partner around E x =18 MeV in 6He and 6Be. 相似文献
90.
Koutaro Shiraishi Hironobu Koseki Toshiyuki Tsurumoto Koumei Baba Mariko Naito Koji Nakayama Hiroyuki Shindo 《Surface and interface analysis : SIA》2009,41(1):17-22
Photocatalysis with anatase Titanium dioxide (TiO2) under ultraviolet A (UVA) has a well recognized bactericidal effect. There have been a few reports, however, on the effects of photocatalysis on bio‐implant‐related infections. The purpose of present study was to evaluate the photocatalytic bactericidal effects of anatase TiO2 on Staphylococcus aureus (S. aureus) associated with surgical site infections. TiO2 films were synthesized on commercially pure titanium substrates and SUS316 stainless steel using a plasma source ion implantation method followed by annealing. The chemical composition of the surface layers was determined using GXRD and XPS. The disks were seeded with cultured S. aureus and exposed to UVA illumination from black light. The bactericidal effect of the TiO2 films was evaluated by counting the survived colonies statistically. A structural gradient anatase type TiO2 layer formed on all substrates. The viability of the bacteria on the photocatalytic TiO2 film coated on titanium was suppressed to 7.0% at 30 minutes and 5.5% at 45 minutes, whereas that on a similarly coated stainless steel was suppressed to 45.8% at 30 minute and 28.6% at 45 minutes (ANOVA: p < 0.05). Complete bacterial inactivation was achieved after 90 minutes on titanium and after 60 minutes on stainless steel. The photocatalytic bactericidal effect of TiO2 is useful for sterilizing the contaminated surfaces of bioimplants. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献