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1.
2.
Shouko Nishida Masaya Shibano Hiroshi Kamitakahara Toshiyuki Takano 《International journal of molecular sciences》2015,16(12):29093-29102
We recently observed that the decanoylation of N-phenylthiocarbamoyl chitosan (2) with a mixture of decanoic anhydride and pyridine at 60 °C for 24 h afforded N,N-(decanoyl)phenythiocarbamoyl-/2-isothiocynato chitosan decanoate (3b) rather than the expected product N,N-(decanoyl)phenylthiocarbamoyl chitosan decanoate (3a). This result suggested that some of the N,N-(decanoyl)phenylthiocarmbamoyl groups had been converted to isothiocyanate groups during the decanoylation process. The subsequent reaction of compound 3b with aniline gave N,N-(decanoyl)phenylthiocarbamoyl/N-phenylthiocarbamoyl chitosan decanoate (4) in high yield. A solution of compound 4 in CHCl3 was then added to a solution of copper decanoate (5) in the same solvent, and the resulting mixture was cast onto a glass plate to give a cast film. The film was annealed at 200 °C in an oven to give a greenish film, which showed good near-infrared absorption characteristic in the range of 800–2200 nm. 相似文献
3.
Toshiyuki MasuiTakanobu Chiga Nobuhito Imanaka Gin-ya Adachi 《Materials Research Bulletin》2003,38(1):17-24
Fine particles of a blue emission phosphor Sr2CeO4 have been synthesized using a chemical co-precipitation technique, and the textual and luminescent properties were compared with the one synthesized by the conventional solid-state reaction method. Particle size and distribution of the Sr2CeO4 fine powder prepared by the co-precipitation process were smaller and narrower than those obtained by the samples prepared from the conventional one. The emission intensity of the fine particles was equal to that of the larger particles prepared from the solid-state reaction, on the contrary to the general tendency that emission intensity decrease with particle size reduction. Although no Ce3+ peaks were observed in EPR measurements, X-ray photoelectron spectra of the samples clearly elucidated the existence of Ce3+ only on the surface of Sr2CeO4. 相似文献
4.
Hiroto Imai Toshiyuki Ogawa Kazuo Sugimoto Masakazu Kataoka Yumo Tanaka Takehiko Ono 《Applied catalysis. B, Environmental》2005,55(4):259-265
The Co/MFI(SiO2/Al2O3 = 30) were prepared by a precipitation method with NaOCl in alkali solutions exhibited high activities to N2 at 250 °C for the selective catalytic reduction (SCR) of NOx. These catalysts showed two UV–vis bands at 700 and 400 nm, indicating the presence of octahedral Co(III) as well as tetrahedral Co(II). The high SCR activity over such Co(III, II)/MFI(30) seems to come from Co(III)---O moieties. The Co(II)MFI(30) catalysts prepared from Co(II)Cl2 exhibited low SCR activities due to the presence of tetrahedral Co(II) ions in MFI. Less CO formation occurred over Co/MFI catalysts. The Fe/MFI(30) catalyst exhibited high activity due to the presence of some Fe---O species in MFI but more amount of CO were produced during SCR. H/MFI(30) catalyst exhibited a good SCR activity. However, more amount of carbonaceous deposits were produced on it. The correlation between acid concentration and SCR activity was discussed over H/MFIs. 相似文献
5.
Shingo Hirano Akio Kawabata Masaru Yoshinaka Ken Hirota Osamu Yamaguchi 《Journal of the American Ceramic Society》1995,78(5):1414-1416
A compound denoted as (Ce0.75 Zr0.25 )O2 (Ce, ZrO8 ) is formed near room temperature from cerium and zirconium nitrates using hydrazine monohydrate. It has a cubic unit cell with a = 0.5342 nm. Characterization of powders heated to various temperatures at 10°C/min demonstrates that the specific surface area does not decrease below 20 mVg until >1000°C. 相似文献
6.
This paper proposes a new belt drive control method for reducing a belt velocity-fluctuation that is caused by a belt thickness-variation in the circumferential direction. A belt driving system performs feedback control with a rotary encoder-output mounted on a driven roller. This proposed method correct the reference value of the feedback control for the purpose of the belt velocity regulation. The correction includes two steps. The first step acquires the encoder-output of the driven roller and calculates the rotational angular velocity-fluctuation with one cycle of the belt rotation. The second step converts from the velocity-fluctuation to the correction value of the feedback reference. The correction value cancels a detection error of the driven roller caused by the belt thickness-variation. After these steps, the belt driving system controls the belt velocity as compensating the belt velocity-fluctuation. Experimental result showed the significant fluctuation reduction on a typical tandem-engine printer. 相似文献
7.
Hydrothermal Synthesis and Low-Temperature Sintering of Zinc Gallate Spinel Fine Particles 总被引:1,自引:0,他引:1
Nanosized powders of single-phase zinc gallate (ZnGa2 O4 ) spinel were hydrothermally synthesized from solutions in the presence of NaOH over the pH range of 1.9 to 7.0 and from solutions above pH 7.0, i.e., the very basic medium (pH of 13.85), by removing the residual ZnO phase by washing with aqueous H2 SO4 from the precipitate mixtures of zinc gallate spinel particles and ZnO. A very wide compositional range (Zn/2Ga = 0.705–1.157) of zinc gallate spinel solid solutions could be hydrothermally synthesized in the form of nanosized particles from acid and very basic mediums (pH of 2.4–13.85) in the presence of NaOH. These hydrothermally synthesized spinel powders showed good sinterability and almost full densification at 1100°C for 1 h. Dense sintered bodies consisting of single-phase zinc gallate spinel were fabricated at 1100°C using zinc gallate spinel powders having almost stoichiometric composition formed from the solution at pH 9.95 in the presence of aqueous ammonia. 相似文献
8.
Morihiko Nakamura Naoyuki Itoh Kenki Hashimoto Tokuzo Tsujimoto Toshiyuki Suzuki 《Metallurgical and Materials Transactions A》1994,25(2):321-330
Isothermally forged TiAl-base alloys (Al-rich, Mn-containing, and Cr-containing TiAl) were heat-treated in various conditions,
and equiaxed grain structures consisting of γ and α2 or Β phases were obtained. The heat-treated alloys were tensile tested in vacuum and air at room temperature, and the environmental
effect on tensile elongation was studied. The ductility of the alloys consisting of equiaxed γ grains and a large amount of
α2 grains was not largely affected by laboratory air, and a decrease in the amount of α2 grains resulted in a large reduction of ductility in air. The Β phase in the Cr-containing alloy improved the ductility in
vacuum, but it resulted in a large reduction of ductility in air.
Formerly with Kougakuin University, Shinjyuku-ku, Tokyo,
Formerly with National Research Institute for Metals, Meguro-ku, Tokyo, 相似文献
9.
Yukihisa Tanaka Jiro Hirano Tadashi Funada 《Journal of the American Oil Chemists' Society》1992,69(12):1210-1214
In an attempt to concentrate the content of DHA (docosahexaenoic acid) in a glyceride mixture containing triglyceride, diglyceride
and monoglyceride, fish oil was hydrolyzed with six kinds of microbial lipase. After the hydrolysis, free fatty acid was removed
and fatty acid components of the glyceride mixtures were analyzed. When the hydrolysis withCandida cylindracea lipase was 70% complete, the DHA content in the glyceride mixture was three times more than that in the original fish oil.
The EPA (eicosapentaenoic acid) content became almost 70% of the original fish oil. Hydrolysis with other lipases did not
result in an increase in the DHA content in the glyceride mixtures. Hydrolysis of DHA-rich tuna oil (DHA content is about
25%) withCandida cylindracea lipase resulted in 53% DHA in the glyceride mixture. The EPA content, however, remained close to that of the original tuna
oil. In this report, the acyl chain specificity of lipases is evaluated in terms of hydrolysis resistant value (HRV). HRV
is the ratio between the DHA contents in the glyceride mixture of hydrolyzed oil and original oil. HRV clearly indicates differences
in hydrolysis between DHA and other fatty acids (e.g., saturated and monoenoic acids). 相似文献
10.
The restoration of the red colour of carthamine (photo-bleached in polymeric heterosaccharide gels) was investigated using sodium salts, potassium salts, and alkali. Ca-alginate gel was stained with carthamine, and the red-dish membranes were exposed to fluorescent light for 2·5, 4·0 and 20 h (at 28°C). The resulting orange-yellow gel membranes were treated with Na- or K-citrate solution and the restoration of the red colouration was followed spectrophoto-metrically. The results indicate that the red colour of carthamine can be retained within the gel membranes, while yellow-coloured compounds were removed and/or transformed by the alkaline salt solutions. 相似文献