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81.
Hiroaki Matsueda Akihiro Ando Sadamichi Maekawa 《Journal of Physics and Chemistry of Solids》2008,69(12):3070-3073
We examine the single-particle excitation and linear optical absorption spectra in the one-dimensional (1D) extended Hubbard-Holstein model. We perform dynamical density matrix renormalization group calculations with use of pseudo-site representation of phonons. We focus on the interplay among phonons and elementary excitations in 1D Mott insulators. The excitations in the Mott insulators are easily modified by the phonons. We discuss implications of the present results in light of spectroscopic measurements in 1D cuprates. 相似文献
82.
Optical Review - This paper proposes a novel steganography method to show an aerial image that is formed with aerial imaging by retro-reflection by use of dual transparent balls made of acrylic... 相似文献
83.
84.
Nuclear magnetic resonance studies of alkaline earth phosphosilicate and aluminoborosilicate glasses
Hiroshi Yamashita Hidetake Yoshino Keishi Nagata Hyuma Inoue Takeshi Nakajin Takashi Maekawa 《Journal of Non》2000,270(1-3):48-59
The 11B, 27Al, 29Si and 31P magic angle spinning (MAS) NMR spectra of MO–P2O5, MO–SiO2–P2O5 and MO(M′2O)–SiO2–Al2O3–B2O3 (M=Mg, Ca, Sr and Ba, M′=Na) glasses were examined. In binary MO–P2O5 (M=Ca and Mg) glasses, the distributions of the phosphate sites, P(Qn), can be expressed by a theoretical prediction that P2O5 reacts quantitatively with MO. In the ternary 0.30MO–0.05SiO2–0.65P2O5 glasses, the 6-coordinated silicon sites were detected, whose population increases in the order of MgOxCaO–0.05SiO2–(0.95−x)P2O5 glasses, its population increases with an increase in f (=([P2O5]−[MO]−[B2O3]−[Na2O])/[SiO2]) and has maximum at f=9. The signal due to the 5-coordinated silicon atoms is also observed when x is smaller than 0.45. When three network-forming oxides such as SiO2, Al2O3 and B2O3 coexist, Al2O3 reacts preferably with MO. The populations of 4-coordinated boron atoms, N4, are expressed well with r/(1−r), where r=([Na2O]−[Al2O3])/([Na2O]−[Al2O3]+[B2O3]). The correlation of the Raman signal at 1210 and 1350 cm−1 with the NMR signal of Si(Q6) at −215 ppm is also seen. 相似文献
85.
Acyloxymethyl radicals were generated from the corresponding iodomethyl esters and successfully underwent addition to the CN bond of N-Ts, N-PMP, and N-Dpp imines by the action of dimethylzinc or triethylborane. Ethyl acetate, toluene, and benzene as well as dichloromethane were suitable solvents. The utility of acyloxymethyl radicals as a hydroxymethyl anion equivalent was highlighted by the facile hydrolysis of the acyloxy moiety of the adducts to give the corresponding amino alcohol derivatives in good to high yield. 相似文献
86.
Equilibrium conditions for clathrate hydrates formed from methane and different concentrations of 1-propanol or 2-propanol aqueous solutions were experimentally determined at temperatures of 274.0–287.1 K and pressures up to 11.0 MPa. Each propanol has an inhibiting and/or promoting effect on hydrate formation depending on the propanol concentration. A structural transition from a structure I to a different hydrate structure occurred at concentrations between 3 and 5 mass% for 1-propanol and between 2 and 3 mass% for 2-propanol. 相似文献
87.
88.
Thomas TD Püttner R Fukuzawa H Prümper G Ueda K Kukk E Sankari R Harries J Tamenori Y Tanaka T Hoshino M Tanaka H 《The Journal of chemical physics》2007,127(24):244309
The boron 1s photoelectron spectrum of (11)BF(3) has been measured at a photon energy of 400 eV and a resolution of about 55 meV. The pronounced vibrational structure seen in the spectrum has been analyzed to give the harmonic and anharmonic vibrational frequencies of the symmetric stretching mode, 128.1 and 0.15 meV, as well as the change in equilibrium BF bond length upon ionization, -5.83 pm. A similar change in bond length has been observed for PF(3) and SiF(4), but a much smaller change for CF(4). Theoretical calculations for BF(3) that include the effects of electron correlation give results that are in reasonable accord with the experimental values. The Lorentzian (lifetime) width of the boron 1s core hole in BF(3) is found to be 72 meV, comparable to the value of 77 meV that has been reported for CF(4). 相似文献
89.
In this review, we describe the regulation of photomovement responses by phototropin and phytochrome photoreceptors. The blue light receptor phototropin mediates various photomovement responses such as phototropism, chloroplast movement and stomatal opening. In cryptogamic plants including ferns, mosses and green alga, red as well as blue light mediates phototropism and chloroplast movement. The red/far-red light reversibility suggests the involvement of phytochrome in these responses. Thereby, plant growth is presumably promoted by coordinating these photomovements to capture efficiently light for photosynthesis. 相似文献
90.
Kanji Suyama Shizue Yamaguchi Masamitsu Shirai Masahiro Tsunooka 《Journal of polymer science. Part A, Polymer chemistry》2000,38(17):3043-3051
Copolymers bearing photoacid generating groups and/or photobase generating groups were dyed after UV irradiation with a dye bath containing both an acid dye and a basic dye. Acetophenone O‐acryloyloxime (AAPO) was used as a monomer bearing acyloxyimino (AOI) group that generates a primary amino group upon irradiation, which is followed by hydrolysis. Phenacylsulfonylstyrene (PSSt) and 1,2,3,4‐tetrahydronaphthylideneamino p‐styrenesulfonate (NISS) were chosen as monomers having β‐keto sulfone (β‐KS) and iminosulfonate (IS) groups, respectively, which yielded acid groups when irradiated. Copolymers of AAPO and methyl methacrylate (MMA) were dyed with only the acid dye, and those of PSSt or NISS were dyed with only the basic dye after irradiation. AAPO‐PSSt‐MMA films became dyeable with the acid dye when irradiated for a short time and with the basic dye with further irradiation. However, AAPO‐NISS‐MMA copolymers showed the reverse dyeing behavior. IR spectra revealed that AOI groups were photochemically decomposed prior to the β‐KS groups for AAPO‐PSSt‐MMA, and AOI and IS groups decomposed simultaneously for AAPO‐NISS‐MMA. These results suggested the possibility of adsorption of different ionic dyes on the films by a change of irradiation time; in fact, color patterns could be obtained in a single staining process using the dye bath. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 3043–3051, 2000 相似文献