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171.
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Abstract A new type of resin wool filter (RWF) that persists the load with oil droplets was developed by Kimura and colleagues. In the present work, the initial collection performances of RWF (A and C) are measured for various particle sizes (0.03, 0.05, 0.1, 0.15, 0.2, 0.25, and 0.3 μm) with different charging states at various filtration velocities (0.05, 0.1, 0.15, and 0.3 m/s). As a result, it is shown that the present RWF impregnated with PTBP resin can attain high collection efficiency (99.999% at filtration velocity of 0.05 m/s) with a pressure drop of less than 30 Pa. The charge density is estimated by applying prediction equations of single-fiber collection efficiencies of electret filters with a dipolar charge distribution because no other prediction equation for RWF are available at present. The experimental single-fiber efficiencies for uncharged particles are successfully predicted by assigning a single value of charge density in the prediction equations for dipolar fibers. The estimated charge density on RWF fibers is 2.1 × 10? 4 C/m2, which is much higher than those of conventional electret filter media. Therefore, RWF studied in the present work is suitable for the application to respirators as well as room air cleaners. 相似文献
173.
Kazutoshi Ohyama Takashi Sugino Tomohiro Nitta Chiharu Kimura Hidemitsu Aoki 《Electrical Engineering in Japan》2011,174(4):45-50
We have attempted to develop high‐performance and safe fuel cells by using ammonium formate as a solid (powder) fuel. This solid fuel has the potential of safer transportability than liquid fuels such as methanol from the viewpoint of toxicity and flammability. In order to make use of some of the advantages of ammonium formate, we investigated the oxidation characteristics of ammonium formate with respect to a Pt electrode. Cyclic voltammograms indicate that ammonium formate has high oxidation activity with respect to a Pt electrode. We have also found that the oxidation of ammonium formate can be improved by the addition of Ir to Pt catalysts. It is highly likely that ammonium formate will be useful as a solid (powder) fuel for polymer electrolyte membrane (PEM) fuel cells. This new fuel will promote the development of safe fuel cells for PEM. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 174(4): 45–50, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21043 相似文献
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175.
Eiji Takeda Takao Watanabe Shinichiro Kimura Jiro Yugami Keiichi Haraguchi Kei Suzuki Katsuro Sasaki 《Microelectronics Reliability》2000,40(6)
The progress of silicon technology is opening the era of “systems on silicon” in which a large-scale memory, a CPU, and other logic macros will be integrated on a single chip. These kinds of chips, called system LSIs, have an especially promising future in mobile and multimedia applications but face inherent technical problems related to the reliability of ultrathin oxide film, conflict in the processing of different components, increased gate and subthreshold leakage currents, memory bottlenecks, and design complexity. This paper reviews the system LSIs and then introduces related technologies in processing, circuits, chip architecture, and design. It also discusses the influence of the system LSIs on business strategies. 相似文献
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177.
The pharmacokinetics of water-in-oil-in-water-type multiple emulsion of a new tacrolimus formulation
Takeji Uno Takaji Yamaguchi Xiao Kang Li Yoshinari Suzuki Hisakuni Hashimoto Yukio Harada Taizou Kimura Teruhisa Kazui 《Lipids》1997,32(5):543-548
We developed a water-in-oil-in-water (W/O/W)-type multiple emulsion of a new tacrolimus formulation. A potential approach
to avoid the complications of systemic immunosuppression and simultaneously enhance immunosuppressive efficacy is to deliver
immunosuppressive agents locally to the site of the target organs. The W/O/W emulsion is dispersed oil drops containing smaller
water droplets that allow the delivery of drugs preferentially to the reticuloendothelial system (RES). Since the liver and
the spleen are primary components of the RES, and the brain and the kidney have a poor RES, we hypothesized that a W/O/W emulsion
of tacrolimus would prossess the pharmacokinetic benefits of local immunosuppression. We evaluated this hypothesis in a rat
model. The tacrolimus levels of whole blood, the liver, spleen, brain, and kidney in rats given intravenous emulsions of tacrolimus
(W/O/W group) were compared with a group administered tacrolimus alone (T group). There were no significant differences between
the pharmacokinetic parameters of W/O/W group and T group based on whole blood data. However, the W/O/W group had significantly
decreased tacrolimus levels in the brain and kidney, and significantly increased levels in the liver and spleen compared with
the T group. These data suggest that the W/O/W emulsion is applicable as an intravenous drug carrier for local immunosuppression. 相似文献
178.
179.
The fundamental modes in an optical waveguide with multiquantum-well structure are analysed by the matrix method. It is found that the separation between the propagation constants of the TE and TM waves is relatively large and that the equivalent planar slab guide approximation is available only for TE waves. 相似文献
180.
The effects of infusion of trieicosapentaenoyl-glycerol emulsion on extravascular lung water during myocardial ischemia and reperfusion in dogs 总被引:2,自引:0,他引:2
Toshio Izuoka Yutaka Kimura Tomohito Hamazaki Teruhiro Tamura Shuji Kitashiro Tetsuro Sugiura Toshimitsu Jikuhara Toshiji Iwasaka 《Lipids》1997,32(1):109-114
To test the effects of eicosapentaenoic acid (EPA) infusion on pulmonary edema induced by coronary ligation and reperfusion,
extravascular lung water (EVLW) was measured in situ by the thermal-dye double indicator dilution method in dogs. In the control group of five dogs, 30 mL of a 10% soybean oil
emulsion was infused through a leg vein. One hour after infusion, the left anterior descending coronary artery below the first
diagonal branch was ligated for 15 min and then reperfused for 30 min. In the EPA group, six dogs were similarly treated with
an emulsion of a 10% trieicosapentaenoyl-glycerol (90% pure). EVLW, pulmonary capillary wedge pressure, mean pulmonary artery
pressure, mean blood pressure, and cardiac index were measured before and 15 min after coronary ligation, and 15 min and 30
min after coronary reperfusion. There were no significant differences in the hemodynamic indices between the two groups. EVLW
significantly increased up to two times of baseline during coronary ligation in the control group (P< 0.05) and more during reperfusion (P<0.01), whereas EVLW did not increase in the EPA group. In conclusion, EPA inhibited EVLW accumulation and may be useful for
ameliorating one of the ischemia-reperfusion-induced complications, pulmonary edema. 相似文献