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61.
Ling Xiao Jinlong Zhang Ye Cong Baozhu Tian Feng Chen Masakazu Anpo 《Catalysis Letters》2006,111(3-4):207-211
Fe3+ doped together with Au deposited TiO2 (Au/Fe3+–TiO2) was successfully prepared, which shows excellent photocatalytic activity for degradation of methyl orange (MO) under both
UV and visible light (λ > 420 nm) illumination. Fe3+ has been confirmed by EPR to substitute for Ti4+ in the TiO2 lattice, and Au exists as Au0 on the surface of the photocatalyst indicated by the results of XRD. Fe3+ and Au have synergistic effects on improving the photocatalytic activity of TiO2. A proposed mechanism concerning the synergistic effects is discussed to explain the improvement of the photocatalytic activities. 相似文献
62.
Masayoshi Ohashi Kazuo Nakamura Kiyoshi Hirao Shuzo Kanzaki Stuart Hampshire 《Journal of the American Ceramic Society》1995,78(1):71-76
Homogeneous Y-Si-O-N glasses containing 15 or 20 eq% nitrogen (N) were prepared from compositions with Y/Si ratios in the vicinity of that of the lowest eutectic point on the Y2 O3 –SiO2 phase diagram. The liquidus on the phase diagram shifted toward lower temperatures by incorporation of N. The density, the elastic moduli, and the glass transition temperature of the Y-Si-O-N glasses increased with incorporation of N. This is due to the closer packing of atoms in the glasses by the substitution of N, which is in three-fold coordination with Si, for O which is in two-fold coordination, and the stronger covalent nature of the Si–N bond compared with the Si–O bond. The coefficient of thermal expansion of the Y-Si-O-N glasses increased with increasing Y content, because the discontinuity of the glass network developed with increasing nonbridging anions by the introduction of Y. In contrast, the glass transition temperature and the elastic moduli increased with Y content due to the high coordination of Y for O, and the relatively high cationic field strength of Y. Furthermore, the effect of cationic field strength on properties of Ln-Si-O-N glasses (Ln = lanthanides or Y) is discussed. 相似文献
63.
Chlorinated polyvinyl chloride (CPVC) is often used in injection molding for products that demand high heat resistance. However, proper control of its flow properties is difficult. To improve flow behavior some internal lubricants are usually used, but they reduce heat resistance of the products. Upper critical solution temperature (UCST) lubricants were found to enhance its flow properties, and also high heat resistance was retained. They act as internal lubricants during processing, improving flow and phase separation during cooling. Therefore they are present essentially as inert filler and thus have little effect on heat distortion temperature. 相似文献
64.
Styrene was grafted onto cellulose acetate p-nitrobenzoate (CANB) by chain transfer reaction of growing polymer radicals to the pendant nitro groups of CANB. A copolymer with a branch for every 17.2 nitro groups was obtained. This result indicates that the pendant aromatic nitro group is more effective in obtaining a graft copolymer by radical mechanism than pendant double bond on the trunk polymer previously reported, where graft copolymers with a branch for several hundred of double bonds are produced. 相似文献
65.
Hiroshi Mori Noritaka Mizuno Masahiro Tajima Shuichi Kagawa Masakazu Iwamoto 《Catalysis Letters》1991,10(1-2):35-39
Proton exchanged ultrastable Y-type zeolite with silica/alumina = 40 showed a pronounced catalytic activity for the formation of ethyl methyl ketone directly from 1-butene and water. The formation rate of ethyl methyl ketone was much higher than those on MoO3-based catalysts in the oxidation of 1-butene by oxygen. It was suggested that the basic site necessary for the formation of ethyl ketone directly from 1-butene and water would be the pentacoordinated Al. 相似文献
66.
Electro-rheological (ER) effect of a blend composed of two liquid crystalline materials with different molecular weights is described in this article. The results indicated that ER effect of the blend was observed at the temperature range where each neat sample did not show ER effect. Furthermore, both storage modulus (G′) and loss modulus (G″) decreased drastically at the temperature range for the blend in dynamic viscoelastic measurements. We show that steady ER effect could be obtained by using a blend made up of two liquid crystalline components, whereas remarkable increment in shear stress was not observed for each component under applied electric field. 相似文献
67.
The complexation between poly(ethylene oxide) (PEO) and poly(acrylic acid) (PAA) was made by using double the molar quantity of either polymer component at pH 2 where the resulting complex completely precipitates. After the removal of the precipitate, PEO or PAA remaining in the supernatant was subjected to gel permeation chromatography to investigate the change in the molecular weight distribution (MWD) caused by the complexation. No remarkable difference is observed in the MWD curves for PEO[1] (Mw=1.37 × 104) before and after the complexation with PAA[1] (Mw=1.10 × 103) and PAA[2] (Mw=4.16 × 105). However, the MWD curves of PEO[2] (Mw=1.26 × 105) and PAA[2] become shortened and shift to the low molecular weight side after the complexation with PAA[1] or [2] and PEO[2], respectively. This tendency is enhanced by increasing the complexation temperature. From these results, it is indicated that the complexation between PEO and PAA deals with an equilibrium reaction, and the equilibrium constant is dependent on the chain length of both polymer components and also on the complexation temperature. 相似文献
68.
Summary Segmented polymers with random sequences of conjugated and non-conjugated blocks are produced by partial dehydrogenation of poly(-thiophenediyl)benzylidene. The fraction of conjugated block was controlled by the elimination time. The polymers gave photoluminescence. Absorption coefficients of the polymers increased with the rate of dehydrogenation, and the highest fluorescence intensity were achieved around 9 % conjugation conversion. The polymers were characterized by 1H- and 13C-n.m.r. and infrared spectra, and were soluble in common organic solvents, which suggests a good processability. 相似文献
69.
Yamauchi Toshihiro Akao Yohei Yoshitani Ryota Nakamura Yuichi Hashimoto Masaki 《International Journal of Information Security》2021,20(4):461-473
International Journal of Information Security - Cyberattacks, especially attacks that exploit operating system vulnerabilities, have been increasing in recent years. In particular, if administrator... 相似文献
70.
Combustion, Explosion, and Shock Waves - Zero-dimensional computations of nanosecond-order ignition using a nanosecond discharge are performed with two constraints. The effects of these constraints... 相似文献