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51.
The [3,3]-sigmatropic rearrangement took place smoothly during the course of trifluoroacetylation of O-phenyloxime at below room temperature to give the dihydrobenzofuran or benzofuran as a result of concomitant cyclization. 相似文献
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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
55.
We synthesized TPP[FeIII(Pc)(CN)2]2, PTMAx[FeIII(Pc)(CN)2]·y(MeCN), and PXX [FeIII(Pc)(CN)2], a new series of charge-transfer salts containing the axially-substituted phthalocyanine (Pc), [FeIII(Pc)(CN)2]−. In this molecular unit, the π conduction electron derived from the Pc-ring coexists with the d electron which is a potential source of a local magnetic moment. Therefore various phenomena associated with the interplay between local magnetic moments and conduction electrons are expected. We observed the giant negative magnetoresistance (GNMR) in all the three salts. The GNMR is highly anisotropic for the magnetic-field direction, and reflects the g-tensor anisotropy of the local magnetic moment in the [FeIII(Pc)(CN)2]− unit. This indicates that the GNMR in these salts originates from the strong π-d interaction in the [FeIII(Pc)(CN)2]− unit. 相似文献
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Naruyoshi Komiya Takeharu Kageyama Masaya Naito Takeshi Naota 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(5):503-505
rac‐Bis{μ‐trans‐2,2′‐[pentane‐1,5‐diylbis(azanediyl)]ditroponato}dipalladium(II), [Pd2(C19H20N2O2)2], has been synthesized and fully characterized using single‐crystal X‐ray diffraction, 1H NMR, FT–IR and mass spectroscopy. The trans coordination, vaulted structure and anti conformation have been unequivocally established from the X‐ray diffraction studies. This is the first example of a bis(aminotroponato)palladium complex. In the crystalline state, the molecule has twofold symmetry and each molecular unit undergoes intermolecular offset π‐stacking of the tropone rings to afford heterochiral interpenetrating dimers that are aligned in a lamellar manner with a herringbone packing motif. 相似文献
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Minemura Y Ito S Miyao T Naito S Tomishige K Kunimori K 《Chemical communications (Cambridge, England)》2005,(11):1429-1431
In preferential CO oxidation in H2-rich gas, K-Pt/Al2O3(K/Pt = 10) was very effective in decreasing CO concentration below 10 ppm in the 375-410 K range, and the turnover frequency of the K-Pt/Al2O3 was 20 times as high as that of Pt/Al2O3 at 353 K; furthermore, the activity of CO oxidation was promoted drastically by the presence of H2. 相似文献
59.
It was found that the periodic change of the solution viscosity and density was generated in the Belousov-Zhabotinsky (BZ) reaction. This rhythmic phenomenon was observed in both the iron catalyst [[Fe(Phen)(3)](2+)-[Fe(Phen)(3)](3+)] and the cerium catalyst [Ce(III)-Ce(IV)] system, where the solution viscosity and density were synchronized with the redox potential in the in-phase mode. However, the time delay existed between the redox potential and the solution viscosity and density. The behavior of the BZ reaction was also monitored in the presence of the nonionic surfactant. This experiment revealed that, beyond the critical micelle concentration, the phase between the redox potential and the solution viscosity and density was synchronized into the antiphase mode. We suggested that the variation of the catalyst drove the oscillation of the solution viscosity and density in the BZ reaction. 相似文献
60.
Flux-flow voltage steps and negative differential resistivity in the cuprate Nd2−xCexCuOy are explained in terms of subbands between the Fermi energy and the energy gap affecting the quasiparticle dynamics. 相似文献