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61.
Watanabe S Sonobe M Arai M Tazume Y Matsuo T Nakamura T Yoshida K 《Chemical communications (Cambridge, England)》2002,(23):2866-2867
A gold nanoparticle surface-modified with amide ligands shows enhanced optical sensing of anions: the detection limit is increased by about three orders of magnitude higher than that originally expected from the anion binding ability of neutral amide ligands. 相似文献
62.
63.
T. Matsuo T. Maekawa A. Inaba O. Yamamuro M. Ohama M. Ichikawa T. Tsuchida 《Journal of Molecular Structure》2006,790(1-3):129
The heat capacities of HCrO2 and DCrO2 have been measured at temperatures between 5 and 360 K. A lambda anomaly occurred at 320 K for DCrO2 but not for HCrO2. Infrared spectra were recorded at temperatures between 5 and 405 K. The spectrum of DCrO2 changed at 320 K with respect to the peak wave-number and splitting of some of the vibrations, while those of HCrO2 depended smoothly on temperature. These experimental results are discussed in terms of a deuteration-induced phase transition. 相似文献
64.
S. Juodkazis H. Okuno N. Kujime S. Matsuo H. Misawa 《Applied Physics A: Materials Science & Processing》2004,79(4-6):1555-1559
We report on the ablation and hole drilling in stainless steel SUS304 and Si by femtosecond pulses (wavelength 800 nm; pulse duration >80 fs) at the room and low (5 Torr) air pressure ambient. It was found that the quality of surface processing is improved at low pressure avoiding debris formation. The improvement is due to suppression of the conical emission, resulting from the air optical breakdown at a pre-surface area of sample. Debris-free processing of the movable Si-MEMS components is demonstrated. Techniques for the precise measurement of focal spot size and pulse duration are discussed. PACS 87.80.Mj; 78.66.Bz; 42.62.Cf; 61.82.Bg; 61.80.-x 相似文献
65.
66.
Yasumitsu Tamura Yasuyoshi Miki Jun-Ichi Minamikawa Masazunu Ikeda 《Journal of heterocyclic chemistry》1974,11(5):675-679
The mono-N-amino salts of 3-phenylcinnoline, phthalazine, 1-phenylphthalazine, 4-phenylquinazoline, 2-phenylquinoxaline, 1,5- and 1,8-naphthyridines are in high yields prepared by direct N-amination of the parent heterocycles with O-mesitylenesulfonylhydroxylamine. With the one expection of 3-phenylcinnoline, the site of N-amination was determined by mass and nmr spectral techniques. The results indicate that the N-amination occurs preferentially at the least sterically hindered nitrogen atom. 相似文献
67.
The absorption bands arising from overtones of the CH stretching vibration of liquid benzene were measured up to the v = 0–9 transition. The transition energies at the band maxima are expressed by a cubic equation. Their bandwidths and oscillator strengths are discussed. 相似文献
68.
The heat capacity of thallium dihydrogen phosphate was measured from 12 to 300 K. A lambda anomaly with a small first order discontinuity was found at 229.76 K with the integrated enthalpy and entropy changes equal to 370 J mol-1 and 1.8 J K-1 mol-1, respectively. The entropy discontinuity at the first order transition is 0.25 J K-1 mol-1. The Landau theory of phase transitions of the second kind reproduces closely the temperature dependence of the anomalous heat capacity. This, together with the small discontinuity in the entropy, implies that the phase transition is close to a classical critical point of higher order. The relative dielectric permittivity ?r(b) along the b-axis at 1 kHz is anomalously large and strongly temperature dependent, while the ?r(a1) and ?r(c) are not. A broad absorption centered at 1700 cm-1 was observed in the infrared absorption spectrum, indicating presence of hydrogen bonding of the length ~ 0.25 nm. Occurrence of a phase transition at 127 ± 2 K was suggested by differential thermal analysis of thallium dideuterium phosphate. 相似文献
69.
H.?SegawaEmail author S.?Matsuo H.?Misawa 《Applied Physics A: Materials Science & Processing》2004,79(3):407-409
Surface corrugation has been photo-induced in a single-step process in hybrid sol-gel thin films. A model based on elastic deformation under photo-induced stress is developed to explain relief formation in this material. Computation is carried out with finite-element software. Theoretical and experimental values of relief amplitude variation with film thickness and grating period agree for small deformations. Mass transfer from illuminated to non-illuminated areas has to be associated with the elastic model to account for surface corrugation in the case of large photo-induced deformation. A comparison with a fluid mechanics model is presented. PACS 81.65.C; 81.20.F; 81.40.L 相似文献
70.
Matsuo Y Tahara K Sawamura M Nakamura E 《Journal of the American Chemical Society》2004,126(28):8725-8734
Selective penta-addition of a methylcopper reagent followed by addition of a phenylcopper reagent to a suitably modified synthetic intermediate results in creation of 40pi-electron systems-hoop- and bowl-shaped cyclic benzenoid compounds, [10]cyclophenacene, and dibenzo-fused corannulene derivatives. The 40pi-electron cyclophenacene derivatives have been found to be chemically stable, yellow-colored, luminescent (560 nm), and EPR-silent. X-ray crystallographic analysis provided precision structural data sets. The dibenzo-fused corannulene derivatives exhibit blue-green (460 nm) to red (649 nm) fluorescence. 相似文献