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31.
Masaru Takahashi Tetsu Nakatani Shinji Iwamoto Tsunenori Watanabe Masashi Inoue 《Applied catalysis. B, Environmental》2007,70(1-4):73-79
The solvothermal reaction of mixtures of aluminum isopropoxide (AIP) and gallium acetylacetonate (Ga(acac)3) directly yielded the mixed oxides of γ-Ga2O3-Al2O3. In the solvothermal synthesis, the crystal structure of mixed oxides was controlled by the initial formation of γ-Ga2O3 nuclei. The mixed oxides prepared in diethylenetriamine have extremely high activities for selective catalytic reduction (SCR) of NO with methane as a reducing agent. With increasing crystallite size of the spinel structure, the catalytic activity increased. The ratio of the amount of methane consumed by combustion to total methane conversion was proportional to the density of acid sites on the surface of the mixed oxides. The mixed oxide catalysts prepared in diethylenetriamine had lower densities of acid sites and showed a higher methane-efficiency for CH4-SCR than those prepared in other solvents. These catalysts maintained their high activity even when the reaction was carried out under the severe conditions (i.e., high space velocity and low NO concentration). 相似文献
32.
Summary Giant hybrid liposomes of polymerizable lipid and cholesterol were prepared by the hydration method and were polymerized by UV irradiation. The obtained giant liposomes were freeze-dried and washed with chloroform to skeletonize the frame structure of the polymerized membrane. The skeletonized liposomes were directly confirmed by scanning electron microscopy. The single-layered and fully spherical liposome frame were easily confirmed by the stereo-pair of the obtained micrographs. 相似文献
33.
A metric of the 3D image quality of autostereoscopic displays based on optical measurements is proposed. This metric uses each view's luminance contrast, which is defined as the ratio of maximum luminance at each viewing position to total luminance at that position. Conventional metrics of the autostereoscopic display based on crosstalk, which uses “wanted” and “unwanted” lights. However, in case of the multiple‐views‐type autostereoscopic displays, it is difficult to distinguish exactly which lights are wanted lights and which are unwanted lights. This paper assumes that the wanted light has a maximum luminance at the good stereoscopic viewing position, and the unwanted light also has a maximum luminance at the worst pseudo‐stereoscopic viewing position. By using the maximum luminance that is indexed by view number of the autostereoscopic display, the proposed method enables characterizing stereoscopic viewing conditions without using wanted/unwanted light. A 3D image quality metric called “stereo luminance contrast,” the average of both eyes' contrast, is proposed. The effectiveness of the proposed metric is confirmed by the results of optical measurement analyses of different types of autostereoscopic displays, such as the two‐view, scan‐backlight, multi‐view, and integral. 相似文献
34.
High oleic acid oil suppresses lung tumorigenesis in mice through the modulation of extracellular signal-regulated kinase cascade 总被引:2,自引:0,他引:2
Yamaki T Yano T Satoh H Endo T Matsuyama C Kumagai H Miyahara M Sakurai H Pokorny J Shin SJ Hagiwara K 《Lipids》2002,37(8):783-788
This study was undertaken to estimate the effect of dietary high oleic acid oil (OA) on 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone
(NNK)-induced lung tumorigenesis in mice. Diet containing 10% oil was fed to mice through experimental periods. On day 30
after NNK injection (100 mg/kg body weight, i.p.), the treatment increased the level of prostaglandin E2 (PGE2) as well as proliferating cell nuclear antigen, a marker of cell proliferation in a high linoleic acid oil (LA)-fed group
but not in an OA-fed group. The NNK treatment also induced the activation of an extracellular signal-regulated kinase (Erk)
cascade (Erk, Mek and Raf-1) in an LA-fed group. On the other hand, OA feeding abolished the NNK-induced activation of the
Erk cascade. In conjugation with these events, OA feeding reduced lung tumor incidence and tumor multiplicity (percentage
of mice with tumors) in mice compared with LA feeding at the 20th experimental week. These results suggest that OA suppresses
lung tumorigenesis and that this suppression is correlated with the inhibition of PGE2 production and inactivation of the Erk cascade. 相似文献
35.
The synthesis of super-microporous aluminosilicate with a pore diameter of 14.6 Å has been achieved, by means of synthesis under specified conditions with a skeletal material comprising TMOS and a small quantity of sodium aluminate, and a conventional alkyl-trimethylammonium halide (C10TMABr) as a template. This super-microporous aluminosilicate has an adsorption capacity of 0.2 ml/g at a relative water vapor pressure of 0.2, and thus is promising as an adsorbent for an adsorption heat-pump. 相似文献
36.
Masaru Takahashi Noriyuki Inoue Tatsuya Takeguchi Shinji Iwamoto Masashi Inoue Tsunenori Watanabe 《Journal of the American Ceramic Society》2006,89(7):2158-2166
The reaction of mixtures of aluminum isopropoxide and gallium acetylacetonate in 1,4-butanediol or 1,5-pentanediol at high temperatures (glycothermal reaction) directly gave the γ-Ga2 O3 –Al2 O3 solid solutions, which had high catalytic activities for selective reduction of NO using methane as the reducing agent. However, the reaction with a higher Al/(Ga+Al) charged ratio yielded the glycol derivative of boehmite as a by-product and the catalytic activity of the solid solution decreased. Therefore, synthesis of the solid solution using various glycols was examined and it was found that solid solutions with high Al contents without contamination of the glycol derivative of boehmite were obtained by using 1,6-hexanediol as a reaction medium. The solid solution exhibited a higher NO conversion than that synthesized in other glycols. 相似文献
37.
In order to obtain thermoplastic (before curing) and thermosetting (after curing) polyimides with high Tg for adhesive film, we prepared novel polyimides having phenylethynyl group in the side chain (44% of concentration of curing group) from asymmetric 2,3,3′,4′-biphenyltetracarboxylic dianhydride (a-BPDA), 3,4′-oxydianiline (3,4′-ODA) or 1,3-bis(4-aminophenoxy)benzene (1,3,4-APB) or 1,3-bis(3-aminophenoxy)benzene (1,3,3-APB), and 2,4-diamino-1-(4-phenylethynylphenoxy)benzene (mPDAp). Among three kinds of polymer, uncured polyimide of a-BPDA/1,3,4-APB; mPDAp had rather high Tg (265 °C, DMA) and thermoplasticity (E′ drop>103 at Tg). After curing reaction of phenylethynyl group, the Tg of the polyimide was increased dramatically (364 °C, DMA). The polyimide derived from 1,3,4-APB having less concentration of curing group (20%) was also prepared to improve further film flexibility and toughness. 相似文献
38.
Yuji Tatemoto Masaya Tsunekawa Shuji Yano Takenari Takeshita Katsuji Noda 《Chemical engineering science》2007,62(8):2187-2197
A relatively large wet material was immersed in a fluidized bed of hygroscopic porous particle (silica gel beads) under reduced pressure. And then the drying characteristics were compared with those in the case of inert particle (glass beads). The comparison of drying characteristics is performed experimentally and theoretically. In calculation, the water transfer from the sample to the fluidized bed was considered. The calculation results are in good agreement with the experimental data. The effects of the operational conditions (the pressure in the drying chamber and the temperature of the drying gas) on the drying characteristics were also examined in both fluidizing particles.The drying finishes earlier in the case of hygroscopic porous particle than in the case of inert particle regardless of pressure in the drying chamber, since the water transfer from the sample facilitates the drying in the case of hygroscopic porous particles. The temperature decrement in drying appears in the case of inert particle. This phenomenon is also observed in the case of hygroscopic porous particle, but the decrement degree of the temperature is much smaller than that in the case of inert particle. The difference of the minimum temperature in the sample in drying between the cases of hygroscopic porous particle and inert particle is very slight for different pressures in the drying chamber. 相似文献
39.
Toshihiko Tanaka Norio Hasegawa Hiroshi Shiraishi Shinji Okazaki 《Polymer Engineering and Science》1992,32(20):1545-1549
The multiple interference effect is one of the major causes of the fluctuation in critical dimension control (CD) and in mark detection for alignment. Suppressing this effect is critical for future photolithography. We propose a new photolithography technique called anti reflective coating on resist (ARCOR), which improves linewidth accuracy and overlay accuracy by suppressing multiple interference. ARCOR consists of relatively simple processes: A clear antireflective film is spun onto the resist prior to the mark detecting for alignment and exposure. The film is subsequently removed and the resist developed in the conventional way. ARCOR differs from ARC, which suppresses the reflection at the resist/substrate interface. ARCOR suppresses the reflection at the air/resist interface. ARCOR allows mark detection and exposure without light intensity-loss and multiple interference. The experiments mainly examine polysiloxane and perfluoroalkylpolyether as ARCOR materials. It is shown that linewidth accuracy can be improved from 0.3 to 0.03 μm. The signal-to-noise ratio of the alignment signal is drastically improved, and the overlay error is about half that of the conventional method. ARCOR is also effective for directly measuring the reflectivity at the resist/substrate interface, which is a key parameter of the multiple interference effect and the halation. Using ARCOR and a thin resist film, the measured ratio of reflected light to incident light indicates the reflectivity at the resist/substrate interface. Because, the probe light does not reflect off the resist surface and the intensity-loss at the resist surface is suppressed. With perfluoroalkylpolyether film, the measurement error is ~ 1.5%. 相似文献
40.