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Song Chen Toshiyuki Ikoma Nobuhiro Ogawa Satoshi Migita Hisatoshi Kobayashi Nobutaka Hanagata 《Science and Technology of Advanced Materials》2010,11(3)
Novel type I collagen hybrid fibrils were fabricated by neutralizing a mixture of type I fish scale collagen solution and type I porcine collagen solution with a phosphate buffer saline at 28 °C. Their structure was discussed in terms of the volume ratio of fish/porcine collagen solution. Scanning electron and atomic force micrographs showed that the diameter of collagen fibrils derived from the collagen mixture was larger than those derived from each collagen, and all resultant fibrils exhibited a typical D-periodic unit of ∼67 nm, irrespective of volume ratio of both collagens. Differential scanning calorimetry revealed only one endothermic peak for the fibrils derived from collagen mixture or from each collagen solution, indicating that the resultant collagen fibrils were hybrids of type I fish scale collagen and type I porcine collagen. 相似文献
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Yi Zhang Jun Bao Satoshi Nagamori Noritatsu Tsubaki 《Applied Catalysis A: General》2009,352(1-2):277-281
A bimodal iron-based catalyst was prepared by a new one-step impregnation method. The active components were used as the “brick” to directly build the small pores inside the large pores of support, which was quite different from the previous bimodal catalysts that were prepared once more on a bimodal support. Comparing with the unimodal catalysts and conventional co-precipitated catalyst, the prepared bimodal catalyst exhibited excellent activity in Fischer–Tropsch synthesis due to the improved active metal dispersion and fastened diffusion efficiency. This preparation method is much simpler than the previous methods and can be extended to prepare various bimodal catalysts with different chemical compositions. 相似文献
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Qiang Dong Nobuhiro Kumada Yoshinori Yonesaki Takahiro Takei Nobukazu Kinomura Dan Wang 《Journal of Materials Science》2010,45(20):5685-5691
Hollow hematite (α-Fe2O3) microspheres with an average diameter of 3-4 μm and a shell thickness of approximate 150 nm was synthesized by a simple
hydrothermal route using FeCl3·6H2O solution and acetic acid without using any templates. The hollow microspheres were composed of α-Fe2O3 nanoparticles with the diameter range from 20 to 40 nm. The effects of reaction parameters such as reaction time, temperature,
concentration of FeCl3·6H2O solution, and initial pH on the morphology of the final products were investigated. A possible formation mechanism of hollow
α-Fe2O3 microspheres was also proposed, where the acetic acid played a role of etching in the formation of hollow structure. 相似文献
149.
Satoshi Tominaka 《Journal of power sources》2009,192(2):316-323
Catalyst layers of direct methanol fuel cells (DMFCs) are modified by in situ electropolymerization of m-aminobenzenesulfonic acid. By using electrochemical impedance spectroscopy and porosimetry, this modification is found to add polymer electrolyte into primary pores (<10 nm), where ionic resistance is high for lack of polymer electrolyte (i.e., Nafion), and the additional electrolyte successfully decreases the ionic resistance by 10-15% compared to the plain carbon surface with a slight ion-conductivity (>40 kΩ cm). In view of methanol oxidation characteristics, this modification decreases the resistance by ca. 25% (from 5.1 Ω cm2 to 3.7 Ω cm2) at 0.6 V vs. DHE, resulting in the increase in the cell voltage of DMFC test by ca. 20 mV. The clear relation between the performance and the microstructures is concluded to be helpful to understand the performance of fuel cell electrodes in detail. 相似文献
150.
Hashimoto T Matsuoka S Yoshimatsu SA Miki K Nishibori N Nishio S Noguchi T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2002,43(1):1-5
The mussel Mytilus edulis and the cultured ark shell Anadara broughtonii in the southeast coasts of the Seto Inland Sea were contaminated with paralytic shellfish poison (PSP) following the appearance of the dinoflagellate Alexandrium tamiyavanichii in early December 1999. A. tamiyavanichii plankton collected around the Straits of Naruto on December 3, 1999 showed PSP toxicity, of which 83 mol% was accounted for by GTX2, GTX3 and GTX4. Its specific toxicity was 112.5 fmol/cell, and one MU was equivalent to 7,200 cells. Toxicity values at the beginning of toxification were 4.7 MU/g for the ark shell and 7.3 MU/g for the mussel. In the former, the value remained at almost 4 MU/g, resulting in prohibition of marketing for about two months. In the latter, it sharply decreased to less than 4 MU/g. These bivalves collected during the toxification period were dissected into five tissues, mantle, adductor muscle, hepatopancreas, gills and "others", and submitted to high-performance liquid chromatography (HPLC). The cultured ark shell accumulated GTX2, GTX3 and STX as major components and GTX1, GTX4, GTX5, neoSTX, dcSTX and PX1-3 (C1-C3) as minor ones. The amount of GTX3 decreased with time, while STX tended to increase. At the early stage of PSP toxification, toxins were accumulated in the gills and "others", most of which were quickly detoxified. On the other hand, PSP of the toxified mussel consisted of GTX4 as a main component, and GTX1, GTX2, GTX3, GTX5, STX and PX1-2 (C1-C2) as minor ones. Its toxin composition pattern was similar to that of the ingested causative plankton. Its total toxin decreased soon after disappearance of the dinoflagellate. During the decrease of toxicity, PSP tended to be retained in the hepatopancreas, resulting in accumulation of 50 mol% of total toxin. 相似文献