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101.
Nano-sized LiMn2O4 particles were prepared at 1023 K by electrospray pyrolysis in which they were directly deposited on a Pt substrate in gas phase. Cyclic voltammetry gave very sharp and symmetrical redox peaks at ca. 4.0 and 4.1 V vs. Li/Li+ owing to the insertion and extraction of lithium-ion at LiMn2O4. However, the redox peaks broadened and their peak separation in an electrode potential increased when aggregated nano-sized LiMn2O4 particles were used. In Nyquist plots, a semi-circle due to lithium-ion transfer resistance appeared at potentials above 3.90 V. The values of the lithium-ion transfer resistances were small for dispersed nano-sized LiMn2O4 particles. On the other hand, the lithium-ion transfer resistances increased and the Warburg impedance became obvious as the nano-sized LiMn2O4 particles aggregated. These results clearly indicate that the apparent rapid diffusion of lithium-ion can be attained using well-dispersed nano-sized particles of electroactive materials. 相似文献
102.
Yoshimasa Yamamoto Phan Trung Nghia Warunee Klinklai Takayuki Saito Seiichi Kawahara 《应用聚合物科学杂志》2008,107(4):2329-2332
The removal of proteins from natural rubber through a batch process was studied by the incubation of the rubber latex with urea in the presence of sodium dodecyl sulfate. Under suitable conditions, the total nitrogen content of deproteinized natural rubber (DPNR) decreased from 0.38 to 0.02 wt % after incubation for 10 min; this was similar to that of the rubber deproteinized with a proteolytic enzyme for 12 h. For applications, continuous incubation and centrifugation were individually investigated by the use of a semicircular channel and a continuous centrifuge, respectively, to scale up DPNR preparation. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
103.
Katsumi Tsuchiya Masanobu Koshihata Tahei Tomida Takayuki Saito 《Korean Journal of Chemical Engineering》1999,16(5):635-639
The dynamic process of gas absorption from a CO2 bubble into a liquid is examined in the presence of satellite bubbles. The bubble under consideration is held stationary,
except its jittering, by the liquid flowing downward. The mass transfer rate is determined by monitoring the rate of reduction
in the equivalent bubble diameter during the initial absorption process. It is found that the interaction with the satellite
bubbles generally hampers the dissolution of the primary bubble. The extent of reduction in the dissolution rate increases
with the net contacting time during the interaction. When the secondary bubbles interact with the primary bubble mainly outside
of its wake, however, the dissolution tends to be enhanced due to induced turbulence in the surrounding liquid flow. A simple
theoretical model is developed to simulate the observed results as well as the basic features prevailing in a recently proposed
scheme, called the GLAD system, for shallow injection of CO2 gas into seawater. 相似文献
104.
Monoclinic hydrous-zirconia fine particles that contained cerium(IV) hydroxide (Ce(OH)4 ) were heated from 200°C to 600°C, to investigate the phase transformation to CeO2 -doped tetragonal ZrO2 . Both ZrOCl2 ·8H2 O and CeCl3 ·7H2 O were dissolved in aqueous solutions and then boiled to prepare the hydrous-zirconia particles. The Ce(OH)4 -containing hydrous-zirconia particles were prepared by adding aqueous ammonia into the boiled solutions. The monoclinic-to-tetragonal ( m right arrow t ) phase transformation of the Ce(OH)4 -containing hydrous zirconias was observed at 300°C using X-ray diffraction (XRD). XRD and Brunauer-Emmett-Teller (BET) specific surface area measurements revealed that the Ce(OH)4 -containing hydrous zirconias had a tendency to transform from the monoclinic phase to the tetragonal phase at lower temperatures as the primary particle size of the hydrous zirconia decreased and the Ce(OH)4 content increased. These tendencies for the m right arrow t phase transformation agree with the conclusions that have been derived from thermodynamic and kinetic considerations. 相似文献
105.
Satoshi Kaneco Kenji Iiba Nobu-hide Hiei Kiyohisa Ohta Takayuki Mizuno Tohru Suzuki 《Electrochimica acta》1999,44(26):4701
The electrochemical reduction of CO2 with a Cu electrode in CsOH/methanol-based electrolyte was investigated. The main products from CO2 were methane, ethylene, ethane, carbon monoxide and formic acid. A maximum Faradaic efficiency of ethylene was 32.3% at −3.5 V vs. Ag/AgCl saturated KCl. The best methane formation efficiency was 8.3% at −4.0 V. The ethylene/methane current efficiency ratio was in the range 2.9–7.9. In the CsOH/methanol, the efficiency of hydrogen formation, being a competitive reaction against CO2 reduction, was depressed to below 23%. 相似文献
106.
Koji Matsui Hidehiro Yoshida Yuichi Ikuhara 《Journal of the European Ceramic Society》2010,30(7):1679-1690
Microstructure development during sintering in 3 mol% Y2O3-stabilized tetragonal zirconia polycrystal doped with a small amount of Al2O3 was investigated in the isothermal sintering conditions of 1300–1500 °C. At the low sintering temperature at 1300 °C, although the density was relatively high, the grain-growth rate was much slow. In the specimen sintered at 1300 °C for 50 h, Y3+ and Al3+ ions segregated along grain boundaries within the widths of about 10 and 6 nm, respectively. In grain interiors, the cubic-phase regions were formed by not only a grain-boundary segregation-induced phase-transformation mechanism but also by spinodal decomposition. The grain-growth behavior was kinetically analyzed using the grain-size data in 1300–1500 °C, which indicated that the grain-growth rate was enhanced by Al2O3-doping. These phase-transformation and grain-growth behaviors are reasonably explained by the diffusion-enhanced effect of Al2O3-doping. 相似文献
107.
Takayuki Saito Warunee Klinklai Yoshimasa Yamamoto Seiichi Kawahara Yoshinobu Isono Yoshito Ohtake 《应用聚合物科学杂志》2010,115(6):3598-3604
Reaction between epoxidized natural rubber and poly(L ‐lactide) (PLLA) was investigated quantitatively in terms of conversion of the epoxidized natural rubber. The epoxidized natural rubber was prepared by epoxidation of high ammonia natural rubber (HA‐NR) or deproteinized natural rubber (DPNR) with peracetic acid followed by depolymerization with ammonium persulfate. The resulting liquid HA‐NR having epoxy group (LENR) or liquid DPNR having epoxy group (LEDPNR) were subjected to heating at 473 K for 20 min, after blending with PLLA. The products were characterized through morphology observation, DSC measurement, and 1H‐NMR spectroscopy. The conversions of the rubbers were estimated from intensity ratio of signals in 1H‐NMR spectrum for the products after removing unreacted rubber with toluene. Difference in the estimated conversion between the LENR/PLLA and LEDPNR/PLLA blends was interpreted in relation to proteins present in the rubber. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
108.
109.
110.
In photodynamic therapy (PDT) for neoplasms, photosensitizers selectively accumulate in cancer tissue. Upon excitation with light of an optimal wavelength, the photosensitizer and surrounding molecules generate reactive oxygen species, resulting in cancer cell-specific cytotoxicity. Porphylipoprotein (PLP) has a porphyrin-based nanostructure. The porphyrin moiety of PLP is quenched because of its structure. When PLP is disrupted, the stacked porphyrins are separated into single molecules and act as photosensitizers. Unless PLP is disrupted, there is no photosensitive disorder in normal tissues. PLP can attenuate the photosensitive disorder compared with other photosensitizers and is ideal for use as a photosensitizer. However, the efficacy of PLP has not yet been evaluated. In this study, the mechanism of cancer cell-specific accumulation of PLP and its cytotoxic effect on cholangiocarcinoma cells were evaluated. The effects were investigated on normal and cancer-like mutant cells. The cytotoxicity effect of PLP PDT in cancer cells was significantly stronger than in normal cells. In addition, reactive oxygen species regulated intracellular PLP accumulation. The cytotoxic effects were also investigated using a cholangiocarcinoma cell line. The cytotoxicity of PLP PDT was significantly higher than that of laserphyrin-based PDT, a conventional type of PDT. PLP PDT could also inhibit tumor growth in vivo. 相似文献