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101.
We give a decomposition formula for the zeta function of a group covering of a graph. 相似文献
102.
103.
Motohiro Mizuno Yoji Aoki Darius Greenidge 《Journal of Physics and Chemistry of Solids》2006,67(4):705-709
The angular dependence of the 27Al NMR spectrum was measured for single crystals of smoky and colorless topaz, Al2SiO4(F,OH)2. Smoky topaz was obtained by irradiating high energy neutrons to colorless topaz. The quadrupole coupling constant e2Qq/h and the asymmetry parameter η were obtained from the analysis of the angular dependences of quadrupole splitting of the 27Al NMR spectrum. The local structures around the aluminum atoms in smoky and colorless topaz were discussed from the magnitude and the direction of the electric field gradient. The directions of principal axes of the EFG tensor of 27Al were close to the directions of Al-O and Al-F bonds. The difference in the bond lengths between Al(1)-F(1) and Al(1)-F(2) was found to affect the x and y components of the EFG tensor. 相似文献
104.
A cyclic dimer of chiral saddle-shaped porphyrin with p-xylylene linkers, upon interaction with mandelic acid, showed an enhanced circular dichroism activity, which was more than 7 times as large as that of a monomeric reference. 相似文献
105.
Shimizu H Fujimoto K Furusyo M Maeda H Nanai Y Mizuno K Inouye M 《The Journal of organic chemistry》2007,72(4):1530-1533
We newly prepared para- and meta-linked alkynylpyrene oligomers and examined their photophysical properties. Oligomerization of monomeric building blocks was performed by CuI-promoted oxidative coupling reaction. The resulting oligomers mainly consist of 2-mer to 6-mer that were assigned on the basis of MALDI-TOF mass spectra, and the 2-mer, 3-mer, and 4-mer were isolated and fully characterized. From their absorption and fluorescence spectra, the para-linked oligomers were found to be somewhat pi-conjugated compared with meta-linked ones, and the fluorescence quantum yields decreased with increasing oligomer length (Phif = 0.79-0.55). 相似文献
106.
Uemura T Kitagawa K Horike S Kawamura T Kitagawa S Mizuno M Endo K 《Chemical communications (Cambridge, England)》2005,(48):5968-5970
The first radical polymerisation of styrene in porous coordination polymers has been carried out, providing stable propagating radicals (living radicals), and a specific space effect of the host frameworks on the monomer reactivity is demonstrated. 相似文献
107.
Dr. Kuirun Zhang Dr. Soonchul Kang Dr. Zi‐shuo Yao Kazusa Nakamura Dr. Takashi Yamamoto Prof. Dr. Yasuaki Einaga Nobuaki Azuma Dr. Yuji Miyazaki Prof. Dr. Motohiro Nakano Dr. Shinji Kanegawa Prof. Dr. Osamu Sato 《Angewandte Chemie (International ed. in English)》2016,55(20):6047-6050
Heterometallic Prussian blue analogues are known to exhibit thermally induced charge transfer, resulting in switching of optical and magnetic properties. However, charge‐transfer phase transitions have not been reported for the simplest FeFe cyanide‐bridged systems. A mixed‐valence FeII/FeIII cyanide‐bridged coordination polymer, {[Fe(Tp)(CN)3]2Fe(bpe)?5 H2O}n, which demonstrates a thermally induced charge‐transfer phase transition, is described. As a result of the charge transfer during this phase transition, the high‐spin state of the whole system does not change to a low‐spin state. This result is in contrast to FeCo cyanide‐bridged systems that exhibit charge‐transfer‐induced spin transitions. 相似文献
108.
Two polyoxometalate assemblies, TBA(9)[{γ-H(2)SiW(10)O(36)Al(2)(μ-OH)(2)(μ-OH)}(3)] (1; TBA = tetra-n-butylammonium) and TBA(6)Li(3)[{γ-H(2)SiW(10)O(36)Al(2)(μ-OH)(2)(μ-OH)}(3)]·18H(2)O (2), were synthesized by trimerization of a dialuminum-substituted silicotungstate monomer. Both 1 and 2 possessed a layered structure composed of a basal sheet unit [TBA(3){γ-H(2)SiW(10)O(36)Al(2)(μ-OH)(2)(μ-OH)}(3)](6-) and interlayer cations. The interconversion between 1 and 2 reversibly took place through interlayer cation exchange. 相似文献
109.
Anisotropic optical properties of mechanically aligned single-walled carbon nanotubes in polymer 总被引:1,自引:0,他引:1
M.?IchidaEmail author S.?Mizuno H.?Kataura Y.?Achiba A.?Nakamura 《Applied Physics A: Materials Science & Processing》2004,78(8):1117-1120
We have prepared aligned single-walled carbon nanotubes in polymer by mechanical stretching. The polarized absorption and Raman spectra of the aligned samples have been investigated. The optical transitions in nanotubes strongly depend on the angle between the polarization of the incident light and the nanotube axis: the absorbance measured at the peak energy shows a maximum at =0°, and they are suppressed at =90°. Raman spectra also show strong polarization dependence, which is mainly determined by the dependence of the oscillator strength of optical transitions in nanotubes. PACS 71.35.Cc; 78.30.-j; 78.67.Ch; 73.22.-f 相似文献
110.
Decomposition of Benzene in Air in a Plasma Reactor: Effect of Reactor Type and Operating Conditions 总被引:2,自引:0,他引:2
Ogata A. Miyamae K. Mizuno K. Kushiyama S. Tezuka M. 《Plasma Chemistry and Plasma Processing》2002,22(4):537-552
The decomposition of benzene was carried out in two types of plasma reactors packed with BaTiO3 pellets: one reactor had two stainless steel electrodes (SUS reactor), and the other reactor had a glass layer between two concentric electrodes (GL reactor). The decomposition efficiency and the suppression of formation of N2O and NOx were greater in the GL reactor than in the SUS reactor. In contrast, the suppression of O3 formation and the oxidation to COx in the SUS reactor were superior to those in the GL reactor. The effect of wa eform and frequency of applied ac power was in estigated for each reactor. 相似文献