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81.
Kohtani S Yoshida K Maekawa T Iwase A Kudo A Miyabe H Nakagaki R 《Physical chemistry chemical physics : PCCP》2008,10(20):2986-2992
Superoxide anion radical (O(2)(-*)) and OH radical generations in suspensions of Ag metal-, Ag(2)O-, or AgO-loaded TiO(2) and BiVO(4) photocatalysts in alkaline conditions (pH 12.0) were examined by means of a luminol chemiluminescence (CL) technique and a spin-trapping fluorescence one in which terephthalic acid reacts with an OH radical to afford the highly fluorescent 2-hydroxyterephthalic acid (TAOH), respectively. The observed luminol CL intensity was remarkably enhanced by the AgO loading on TiO(2) as well as BiVO(4). This can be explained by enhancement of O(2)(-*) production on the AgO-loaded photocatalysts caused by the synergetic effects on the thermocatalytic activity upon the AgO surface and the efficient electron-hole separation at the photocatalyst/AgO interface. On the other hand, loading effects of AgO on the TAOH formation were not so significant compared to those on the CL observation, though the TAOH formation rates for the TiO(2) samples were much larger than those for the BiVO(4) ones by about three orders of magnitude. The properties of O(2)(-*) and OH radical generations on these photocatalysts are discussed on the basis of the luminol CL kinetics and approximate band edge positions of TiO(2), BiVO(4), and silver oxides. 相似文献
82.
Haruya Inuzuka Daisuke Urushihara Toru Asaka 《Journal of solid state chemistry》2010,183(11):2570-2575
A new aluminum oxycarbonitride, Al5(OxCyN4−x−y) (x∼1.4 and y∼2.1), has been synthesized and characterized by X-ray powder diffraction, transmission electron microscopy and electron energy loss spectroscopy (EELS). The title compound was found to be hexagonal with space group P63/mmc, Z=2, and unit-cell dimensions a=0.328455(6) nm, c=2.15998(3) nm and V=0.201805(6) nm3. The atom ratios O:C:N were determined by EELS. The final structural model, which is isomorphous with that of (Al4.4Si0.6)(O1.0C3.0), showed the positional disordering of one of the three types of Al sites. The maximum-entropy method-based pattern fitting (MPF) method was used to confirm the validity of the split-atom model, in which conventional structure bias caused by assuming intensity partitioning was minimized. The reliability indices calculated from the MPF were Rwp=6.94% (S=1.22), Rp=5.34%, RB=1.35% and RF=0.76%. The crystal was an inversion twin. Each twin-related individual was isostructural with Al5C3N (space group P63mc, Z=2). 相似文献
83.
Novel terephthalic acid host compounds having aromatic substituent 1-4 have been prepared and their inclusion properties were investigated. These host compounds enclathrated several kinds of alcohols, ethers, ketones, amides, and sulfoxides. The X-ray structures of 1:1 2a/EtOH, 1:2 2b/DMF, 1:2 3/MeOH, and 1:1 4/EtOH complexes revealed complexation mode. 相似文献
84.
Synergistic hybrid catalyst for cyclic carbonate synthesis: remarkable acceleration caused by immobilization of homogeneous catalyst on silica 总被引:3,自引:0,他引:3
Takahashi T Watahiki T Kitazume S Yasuda H Sakakura T 《Chemical communications (Cambridge, England)》2006,(15):1664-1666
The catalytic activity of phosphonium salts towards cyclic carbonate synthesis from propylene oxide and CO2 has been enormously enhanced by their immobilization onto silica that itself has no catalytic activity. 相似文献
85.
Poly(epsilon-caprolactone) (PCL) composite samples were prepared by polymerization and direct molding. The starting compound was epsilon-caprolactone monomer liquid combined with cellulose and inorganic fillers, using aluminium triflate as a catalyst at 80 degrees C, for 6 or 24 h. Cylinder-shaped PCL composite samples with a homogeneously dispersed cellulose filler were prepared with (-)M(n) = 4 600 ((-)M(w)/(-)M(n) = 2.9). The mechanical properties of the PCL composite samples were studied using compression test methods. The strength of a PCL composite with 50 wt.-% cellulose filler (10.8 MPa) was found to be lower than the PCL sample without fillers (19.2 MPa). The biobased content of the PCL composite with 50 wt.-% cellulose filler (51.67%) measured using accelerated mass spectrometry (AMS) was slightly higher than the carbon ratio of cellulose in the starting powder samples (41.3 mol-%). The biobased content of the polymer composite powders by AMS was found not to be affected by the presence of inorganic fillers, such as talc. The rate and extent of biodegradation, caused by Amano Lipase PS, of the PCL composite sample with cellulose filler (40% degradation in 4 d) was the same as that of a PCL sample without the cellulose filler. 相似文献
86.
Maho Morita Osamu Ohno Toshiaki Teruya Takao Yamori Toshiyasu Inuzuka Kiyotake Suenaga 《Tetrahedron》2012,68(30):5984-5990
Bioassay-guided fractionation of the marine cyanobacterium Lyngbya sp. led to the isolation of biselyngbyasides B (3), C (4), and D (5), novel analogs of biselyngbyaside (1) and biselyngbyolide A (2). The gross structures of 3–5 were determined by NMR spectral analyses, and their stereochemistries were established based on NOESY spectra and CD data. Biselyngbyasides (1–3) showed growth-inhibitory activity and apoptosis-inducing activity against both HeLa S3 cells and HL60 cells. The fura-2 method revealed that biselyngbyasides (1–3) increased the cytosolic Ca2+ concentration in HeLa S3 cells. 相似文献
87.
Toshiyasu Arai 《Annals of Pure and Applied Logic》2010,162(2):107-143
In this paper, we give two proofs of the wellfoundedness of a recursive notation system for ΠN-reflecting ordinals. One is based on distinguished classes, and the other is based on -inductive definitions. 相似文献
88.
Toshiyasu Arai 《Archive for Mathematical Logic》2018,57(5-6):649-664
In this note the well-ordering principle for the derivative \(\mathsf{g}^{\prime }\) of normal functions \(\mathsf{g}\) on ordinals is shown to be equivalent to the existence of arbitrarily large countable coded \(\omega \)-models of the well-ordering principle for the function \(\mathsf{g}\). 相似文献
89.
90.
Imidoyl chlorides were successfully transformed into ketimines when treated with organotin compounds in the presence of palladium complex catalysts. 相似文献