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41.
Sasamori T Hironaka K Sugiyama Y Takagi N Nagase S Hosoi Y Furukawa Y Tokitoh N 《Journal of the American Chemical Society》2008,130(42):13856-13857
Synthesis and isolation of the stable diaryldibromodisilene, Bbt(Br)SiSi(Br)Bbt, has been accomplished for the first time. The dibromodisilene underwent substitution reactions with organometallic reagents on the low-coordinated silicon atom to afford the corresponding substituted disilenes. Furthermore, the reaction of 1 with t-BuLi afforded the corresponding 1,2-diaryldisilyne, BbtSi[triple bond]SiBbt, the characters of which were revealed by spectroscopic and crystallographic analyses. 相似文献
42.
Hosoi H Yamaguchi S Mizuno H Miyawaki A Tahara T 《The journal of physical chemistry. B》2008,112(10):2761-2763
Precise two-photon absorption spectra of the green fluorescent protein (GFP) and the mutants sapphire-GFP (T203I) and enhanced GFP (S65T/F64L), as well as a model compound for the chromophore, 4'-hydroxybenzylidene-2,3-dimethylimidazolinone (HBDI) were measured by multiplex two-photon absorption spectroscopy. The observed TPA bands of the anionic forms of enhanced GFP and HBDI were significantly shifted to the higher energy compared with the lowest-energy bands in one-photon absorption spectra. This result indicated the existence of a hidden electronic excited state in the vicinity of the lowest excited singlet (S1) state of the anionic form of the GFP chromophore, which is the origin of the blue shift of the two-photon absorption spectra as well as two-photon fluorescence excitation spectra. 相似文献
43.
Iida T Ogawa S Hosoi K Makino M Fujimoto Y Goto T Mano N Goto J Hofmann AF 《The Journal of organic chemistry》2007,72(3):823-830
tert-Butyl hydroperoxide catalyzed by (5,10,15,20-tetramesitylporphyrinate) osmium(II) carbonyl [Os(TMP)CO] complex was found to be a highly efficient versatile oxidant for C-H carbons in steroid substrates. When reacted with representative steroids with an estrane, pregnane, 5beta-cholane, or 5alpha-cholestane structure, regioselective oxyfunctionalization and/or oxidative degradation occurred to give a variety of novel and uncommon derivatives in one step. 相似文献
44.
Tanaka M Ubukata M Matsuo T Yasue K Matsumoto K Kajimoto Y Ogo T Inaba T 《Organic letters》2007,9(17):3331-3334
A ring-opening reaction of cyclopropanes with five-membered heteroaromatics having a leaving group at C(2) was found to provide heteroaromatic-fused pyrrolidines in one step. This reaction was successfully applied to the synthesis of the protein kinase C-beta inhibitor JTT-010, which possesses a dihydropyrrolo[1,2-a]indole core. 相似文献
45.
The concentration dependence of the CO stretching (νCO) band of N,N-dimethylacetamide (NdMA) in cyclohexane, n-hexane, and CCl4 has been investigated by infrared (IR) and polarized Raman spectroscopy. For the neat liquid of NdMA, the noncoincidence of the aniso- and isotropic Raman wavenumbers is evident. In the 0.47 M cyclohexane solution of NdMA, the noncoincidence effect almost disappears and the νCO envelopes in both the Raman and IR spectra are asymmetric to the low-wavenumber side. When the concentration of NdMA decreases from 0.33 to 0.023 M, the peak of these bands slightly shifts to a higher wavenumber and the band shape becomes symmetric. The shape of the νCO envelope does not show any significant change below 0.023 M. These results suggest that the asymmetric shape of the νCO band observed for the 0.33 M cyclohexane solution is associated with the intermolecular interaction among NdMA molecules, which vanishes at around 0.02 M. Spectral changes for the CCl4 solution of NdMA show a similar tendency. However, the shape and peak wavenumber of the νCO band observed in a highly diluted CCl4 solution (≤0.023 M) indicate that the solvation effect of CCl4 is more complicated than those of cyclohexane and n-hexane. The analyses of the νCO band, which is sensitive to the intermolecular interaction between solutes and between solute and solvent for NdMA dissolved in nonpolar solvents, would serve to clarify the electronic property of the molecule in a solution. 相似文献
46.
Fumio Hosoi Yasushi Aoki Miyuki Hagiwara Hideki Omichi M. Mat. Salleh 《辐射效应与固体损伤》2013,168(1-4):351-354
Abstract Substituting metallic or rare-earth atoms or removing O in the superconductor YBa2Cu3O7 usually has a strong effect on the superconducting properties. We have made extensive XAFS studies on Co, Fe, Ni, Zn, Gd, and Pr substituted materials including some thin film samples. In nearly all cases, significant distortions are found. Although the lattice constant change is small (< 0.05 Å) the local distortions can be significant larger (~ 0.1 to 0.3 Å). The observed large local distortions of the lattice together with a change in the charge distribution at a site indicate that the interior of the unit cell is easily distorted. The correlation of a strong Tc suppression with large local distortions suggests that distortions of the nearby layers must play a significant role in models for superconductivity in high Tc materials. 相似文献
47.
Within the framework of the general theory of stochastic calculus of variations, we examine mainly the notion of second variation in the stochastic mechanics of E. Nelson, a representative of quantum mechanics in which the concept of path for particles keep a sense. We show that the two approaches used in classical calculus of variation to know if a path is not only an extremum but also the minimum of the action, namely, the local one (weak minimum) and the global one (strong minimum), can be generalized to include the quantum-mechanical paths. Thus, we can prove that locally, a solution of the classical equation of motion is really the minimum, even in a large class of quantum paths containing the semi-classical trajectories. By introducing a stochastic version of the excess function of Weierstrass, we show the analogous global property. There, of course, one can speak of the principle of least action in a strict sense. Several explicit examples are discussed. 相似文献
48.
S. Toyooka Y. Iwaasa M. Kawahashi K. Hosoi M. Suzuki 《Optics and Lasers in Engineering》1985,6(4):203-212
A new method for the automatic processing of Young's fringes in speckle photography is described, based on the technique of spatial phase detection. The amount of calculation is reduced, yet accuracy is of an order comparable with that of the Fourier transform method. Furthermore, orientation of fringes is determined as well as fringe spacing. 相似文献
49.
S. Kubono N. Ikeda M. Yasue T. Nomura Y. Fuchi H. Kawashima S. Kato H. Orihara T. Shinozuka H. Ohnuma H. Miyatake T. Shimoda 《Zeitschrift für Physik A Hadrons and Nuclei》1988,331(3):359-360
The first excited state above the p +19Ne threshold in20Na has been identified at 2.637 MeV (± 15 keV) with Jπ=0+ or 1+ from the20Ne(3He, t)20Na reaction, suggesting this state to be the s-wave resonance in the p +19Ne scattering at stellar energies. 相似文献
50.
D. Fink R. Klett M. Müller H. Omichi F. Hosoi J. Vacik V. Hnatowicz L. T. Chadderton 《Applied Physics A: Materials Science & Processing》1996,63(5):441-446
Li salts of acrylic acid were grafted to polyethylene, PE. It is known that li is mobile in this material at room temperature, and hence can act as a probe for newly introduced defects. After irradiation of PE(Li) with 100 keV He+ ions at different fluences the Li depth distributions were measured by NDP. Changes in the Li distributions are observed which are ascribed to bonding at oxygen, the latter one preferentially penetrating into the PE via the irradiation-damaged sample surface. With increasing sample age, i.e. after exposure to ambient atmosphere for more than half a year, Li appears to lose its original mobility. 相似文献