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941.
Takuya Oda M Masaaki Sakagami Hiroyuki Ito M Hiroshi Yano Shiba K. Rai Masato Kawabata Shoji Uga 《Water research》2000,34(18):4477-4481
We describe a size selective continuous flow filtration method for detecting Cryptosporidium oocyst and Giardia cyst in finished water. Twenty liters of finished water spiked with Cryptosporidium oocysts (110) and Giardia cysts (60) were filtered through macro (5.0–10.0 μm) and micro (3.0 μm) pore-sized polycarbonate-track-etch (PCTE) membrane filters housed into two separate 47 mm diameter filter holders joined with a stainless steel nipple. The macro-pore-sized filters removed larger unwanted particles while allowing the Cryptosporidium oocysts and Giardia cysts to pass through, these being subsequently captured on the micro-pore-sized filter. The eluted oocysts and cysts were transferred onto the well-slide, stained by IFA and examined microscopically. The mean recovery efficiencies obtained for Cryptosporidium oocysts using the filter pairs of macro 5 μm and micro 3 μm, macro 8 μm and micro 3 μm, and macro 10 μm and micro 3 μm were 67.3%, 77.2–85.0% and 76.9–82.2%, respectively. Whereas the recovery rates for Giardia cysts using the same filter pairs were 0, 55 and 77.1%. The filter pair having the pore size of macro 10 μm and micro 3 μm was found to be most efficient in the simultaneous detection of Cryptosporidium and Giardia in the finished water. This method is simple, easy, rapid and economical. 相似文献
942.
<正>多摩美术大学图书馆是日本建筑大师伊东丰雄(Toyo Ito)的新作,坐落在东京多摩美术大学八王子校区内,位于一座公园后略微倾斜的草坪上。设计伊始,伊东丰雄领导的团队计划将整座图 相似文献
943.
Satoshi Sakauchi Makoto Hattori Tadashi Yoshida Takahiro Yagishita Koichi Ito Shin-ichi Akemitsu Koji Takahashi 《Journal of food science》2010,75(2):C177-C183
ABSTRACT: The particular effect of 4 kinds of amino acid and peptide-rich food material (APRM) containing different charged amino acid contents on the gelatinization and retrogradation behavior of potato starch granules and on the water-vaporization behavior was analyzed by differential scanning calorimetry, rapid viscoanalysis, x-ray diffractometry, thermal gravimetry-differential thermal analysis, and pulsed NMR. APRM with a high-charged amino acid content produced unique gelatinization and retrogradation behavior in terms of an elevated gelatinization temperature, reduced viscosity, higher setback, and lower retrograded starch melting enthalpy. The recovered x-ray diffraction intensity decreased with increasing charged amino acid content. APRM with high-charged amino acid content could provide an improved paste having easy vaporization of external water in the swollen starch granules due to the reduced swelling. 相似文献
944.
Dongyun Guo Akihiko Ito Takashi Goto Rong Tu Chuanbin Wang Qiang Shen Lianmeng Zhang 《Journal of Materials Science: Materials in Electronics》2013,24(6):1941-1946
BaTi5O11 films were prepared on Pt/Ti/SiO2/Si substrates by a laser chemical vapor deposition method. The effect of laser power (P L) on the electrical conductivity of the BaTi5O11 films was investigated. The electrical resistivity of the grains was much higher than that of the grain boundaries, which indicated that the electrical conductivity along the grain boundary was dominant. For the BaTi5O11 films, the conduction was mainly attributed to oxygen vacancies, and the electrical conductivity was strongly affected by their microstructures and the concentration of the charge carriers. With increasing the P L, the grain size increased and the grain-boundary density decreased, which resulted in the decrease of the electrical conductivity. At the same time, the increase of T dep led to higher concentration of charge carriers, which resulted in the increase of electrical conductivity. 相似文献
945.
Yu-Ya Hosokawa Hideki Hakamata Tomonori Murakami Sakae Aoyagi Minpei Kuroda Yoshihiro Mimaki Ayumi Ito Sayaka Morosawa Fumiyo Kusu 《Electrochimica acta》2009,54(26):6412-6416
Cholesterol was shown to be oxidized at the glassy carbon electrode in an acetonitrile–2-propanol mixture and this oxidation reaction was applied to the determination of serum total cholesterol by high-performance liquid chromatography with electrochemical detection (K. Hojo, H. Hakamata, A. Ito, A. Kotani, C. Furukawa, Y.Y. Hosokawa, F. Kusu, J. Chromatogr. A 1166 (2007) 135–141). To gain insight into the detection mechanisms of cholesterol, an electrolytic product of cholesterol was collected and characterized by infrared spectroscopy, one- and two-dimensional nuclear magnetic resonance, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The three techniques, together with comparisons of literature spectral data, confirmed the formation of cholesta-4,6-dien-3-one. The conversion of cholesterol to cholesta-4,6-dien-3-one, a four-electron, four-proton electrochemical process, has been proposed as an electrochemical oxidation mechanism of cholesterol in acetonitrile. 相似文献
946.
Saba Samatya Hidenobu Mizuki Yudai Ito Hidetaka Kawakita Kazuya Uezu 《Reactive and Functional Polymers》2010,70(1):63-68
A novel adsorbent, Zr(IV)-immobilized resin, was prepared by surface template polymerization. This adsorbent, prepared by adding polystyrene (PS) to resin, has a high adsorption capacity for the removal of fluoride ion from aqueous solutions. The adsorption capacity increased with rising PS concentration, since the specific surface area can be effectively increased by adding polystyrene as a porogen. The adsorption isotherm has been modeled by the Langmuir and Freundlich equations. The adsorption isotherms were well described by the Langmuir equation. The removal of fluoride was also carried out using a column method. The presence of PS in the resin exerted a remarkable influence on the uptake of fluoride ion. The fluoride adsorbed on the resin was quantitatively eluted with 0.1 M NaOH. 相似文献
947.
Akira Ito Masashige Shinkai Kazumi Hakamada Hiroyuki Honda Takeshi Kobayashi 《Journal of Bioscience and Bioengineering》2001,92(6):598
We demonstrated the effectiveness of radiation-inducible expression of the TNF-α gene for cancer therapy in vitro. The TNF-α gene under the control of the stress-inducible promoter, gadd 153, was introduced into the human glioma cell line, U251-SP. Without cobalt-60 gamma irradiation, no cytotoxicity against the transfected cells was observed. When the transfected cells were irradiated with 10 or 20 gray (Gy), the gadd 153 promoter was highly induced and the expression level of TNF-α increased. Five days after the irradiation, the TNF-α productions of each cell irradiated with 10 and 20 Gy were 30 and 100 times higher than the basal level, respectively. The cytotoxicities against the transfected cells 5 d after irradiation with 10 and 20 Gy were 79% or 91%, respectively, which are much higher than those against the nontransfected cells that were irradiated at the same dose (43% and 78%, respectively). These results demonstrate that the gadd 153-TNF-α system may be an effective tool for radiosurgery of malignant brain tumors. 相似文献
948.
Hironori Tohmyoh Yusuke Ito Kazuteru Eguchi Wataru Daido Jiro Utsunomiya Yoshikatsu Nakano 《应用聚合物科学杂志》2012,124(5):4213-4221
The creep properties, that is, the velocity constant, activation energy, stress index, and time index, of a test piece (TP) cut from a glass‐fiber‐reinforced nylon 6 product were successfully determined by a compression creep test. In the determination of the creep properties, the experimental creep curves for the TP were fitted by finite element analysis (FEA). Fiber‐reinforced nylon 6 beams with different fiber orientations were also prepared, and their creep properties were successfully determined by a combination of the bending creep test and the corresponding analysis. The creep behavior of the press‐fit component composed of a metal collar and a fiber‐reinforced nylon 6 product was predicted by FEA with the determined creep properties of the TP. The predicted retention forces were in good agreement with the experimental ones. The effects of the fiber orientation on the long‐term reliability of the press‐fit component are also discussed. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
949.
In this research, we have developed a swimming robot with a fluttering kick with two legs, which can swim freely both on the
surface of water and under water. We have established a control method for all the different types of motion of this robot,
e.g., swimming in a straight line, turning, diving, or rising up in the water. Furthermore, by optimizing the three-dimensional
action of this underwater robot, we can expect an improvement in its performance for complex work. 相似文献
950.
Kun'ichi Miyazawa Kunio Ito Joachim Mayer Manfred Rühle 《Journal of the American Ceramic Society》1998,81(9):2333-2341
Multilayer PZT films were prepared by sol-gel processing, and their structure and composition were investigated by cross-sectional TEM and EDX analyses. The films made by firing at 600°C (as-deposited films) are composed of alternating porous and dense layers, and the porosity increases by a factor of 2 through heating at 750°C. The pyrochlore phase observed in the as-deposited films turns to the perovskite phase by the heat treatment at 750°C. The Ti/Zr ratio along the film stacking direction is shown to change with the elevation of heat treatment temperature. The porous soft layers are considered to reduce the thermal stress and prevent the introduction of cracks during the firing process. 相似文献