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51.
Hiroki Nagasawa Akihiro Yamasaki Atsushi Iizuka Kazukiyo Kumagai Yukio Yanagisawa 《American Institute of Chemical Engineers》2009,55(12):3286-3293
Bipolar membrane electrodialysis is applied to CO2 recovery from alkaline carbonate solution. CO2 in flue gas is captured by an alkaline hydroxide absorbing solution to form an alkaline carbonate solution. The captured CO2 is recovered from the alkaline carbonate solution via bipolar membrane electrodialysis, and the alkaline solution is regenerated simultaneously. To reduce the power requirement for CO2 recovery, this study considers optimal design and operation. Three membrane arrangements were compared, and the results indicate the membrane arrangement comprising a bipolar membrane and cation exchange membrane is the most energy saving. With further optimization of operation conditions, the minimum power requirement for CO2 recovery was reduced to 2.1 MJ/kg‐CO2 (or 2.1 GJ/t‐CO2). © 2009 American Institute of Chemical Engineers AIChE J, 2009 相似文献
52.
Satoshi Azuma Hisanori Yamasaki Daisuke Itoh Takafumi Maruyama 《Electrical Engineering in Japan》2008,165(4):84-91
A newly proposed energy‐compensating active control is implemented to reduce the return current noise which is caused by inverter‐driven electric car systems. The energy‐compensating active control detects the energy charged at the filter capacitor, and reduces the energy and current of the noise frequency component by simple feedback loop incorporated with the conventional motor torque controller. No additional sensors or circuit arrangements are necessary; therefore, the return current can be attenuated effectively without any further cost. The return current with an inverter system is measured using a current probe and an FFT analyzer, and it is shown that the 25‐Hz noise current is reduced by up to 10 dB with the control. The results reveal that the low‐frequency return current noise can be attenuated with the simple control scheme, which would expectedly reduce the size of filter reactors and capacitors to meet the current limit level of the signaling system's track relays. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 165(4): 84–91, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20615 相似文献
53.
Yamasaki T. Shima K. Komori S. Takata H. Tamura T. Asai F. Ohno T. Tomisawa O. Terada H. 《Solid-State Circuits, IEEE Journal of》1989,24(4):933-937
A VLSI-oriented variable-length pipeline structure for data-driven processors is presented. Ordinary inline pipelines have the problem of minimizing the average total processing time through the pipeline, since subdivision of a function along the pipeline is usually optimized for the most complex operations in spite of the fact that simpler operations need fewer stages. As a solution to this problem, a variable-length pipeline scheme in which data go through only the necessary stages according to information contained within is proposed. The scheme has been implemented on a test chip to verify performance. The chip demonstrated a minimum fall-through time (data transmission time from input to output) of 14.4 ns and a data transmission rate in the pipeline of 59 megaword/s (that is, 1/16.9 ns) as a first-in first-out (FIFO) store. By modifying the data transfer control and allocating the processing functions corresponding to the data interval of 16.9 ns, this scheme is applicable as a high-performance processing unit for data-driven processors 相似文献
54.
K Tokinaga K Inoue I Yamasaki A Yamashita M Yamashita T Shuin Y Kamei 《Canadian Metallurgical Quarterly》1997,43(10):731-733
A 33-year-old man who had been treated for chronic prostatitis was diagnosed to have urachal cysts by transabdominal ultrasonography. Cystoscopy revealed protuberance at the dome of the bladder. Computerized tomography scan and magnetic resonance imaging showed the mass to be mostly cystic but partly solid. Resection of the urachal cysts and partial cystectomy were performed. Histopathologically, most cysts had a normal cylindrical epithelium with retention of mucinous substance. However, several small cysts contained epithelial cells resembling tubulo-villous adenoma and showing mitotic figures. This case was concluded as urachal carcinoma detected in its very early stage. 相似文献
55.
Origin of the Red Color of Satsuma Copper-Ruby Glass as Determined by EXAFS and Optical Absorption Spectroscopy 总被引:1,自引:0,他引:1
Izumi Nakai Chiya Numako Hideo Hosono Kazuo Yamasaki 《Journal of the American Ceramic Society》1999,82(3):689-695
The origin of the ruby color of Satsuma glass, a famous copper-ruby glass produced in Japan in the mid-19th century, has been examined by electron microprobe analysis (EPMA), X-ray absorption fine structure (XAFS), and optical absorption spectroscopy analyses. Cu K XAFS analysis reveals that the major component of copper in the ruby glass consists of Cu(I) ions in the glass structure. This species is distinct from Cu2 O (cuprite), which we conclude is not responsible for the ruby color. Optical absorption spectra measured at 300 and 77 K clearly distinguishes the absorptions due to the colloidal particles of metallic copper and Cu2 O. It is concluded that the trace amount of copper in the ruby glass, which is below the detection limit of the EPMA and XAFS techniques, exists as metallic copper particles of nanometer size and is responsible for the ruby-red appearance of the Satsuma glass. 相似文献
56.
Catalytic gasification of a woody biomass, Japanese cypress, was investigated under a prepared nickel-loaded brown coal (LY-Ni) char in a two-stage fixed-bed reactor. The nickel-loaded brown coal was prepared by ion-exchange method with a nickel loading rate of 8.3 wt.%. Nickel species dispersed well in the brown coal, and the LY-Ni char via devolatilization at 600 °C showed a great porous property with a specific surface area of 382 m2 g− 1.The LY-Ni char was confirmed to be quite active for the Japanese cypress volatiles gasification at a relatively low-temperature range from 450 to 650 °C. For example, at 550 °C, 16.6 times hydrogen gas and 6.3 times total gases were yielded from the catalytic steam gasification of Japanese cypress volatiles under the LY-Ni char, compared with the case of non-catalyst. The biomass tar decomposition showed a dependence on catalyst temperatures. When the catalyst temperature was higher than 500 °C, Japanese cypress tar converted much efficiently, high gas yields and high carbon balances were obtained. 相似文献
57.
Furukawa S Narisawa N Watanabe T Kawarai T Myozen K Okazaki S Ogihara H Yamasaki M 《International journal of food microbiology》2005,102(1):107-111
Effects of the clumping of bacterial spores on their heat resistance as a result of heat treatment were investigated. Spore suspensions of Bacillus cereus, Bacillus coagulans and Bacillus licheniformis were heated at 85 degrees C. Survivor curves of the three strains showed tailing in all treatments after 30 min. As the treatment time increased, the formation of spore clumps increased in all strains after 20 min. Relative hydrophobicity of the spore surface increased as a result of heat treatment. The effect of spore concentration on the inactivation of the B. licheniformis spores was investigated, and surviving curves showed no tailing below a concentration of 4.9 log CFU/ml. 相似文献
58.
Lactoperoxidase (LPO) is a milk protein with antimicrobial function. The present study was undertaken to examine the correlation between LPO activity and somatic cell count (SCC) in milk to use LPO activity as an indicator of mastitis. Composite milk of 36 cows and quarter milk of 3 cows were collected once per week from 0 to 300 d postpartum and twice per day for 1 wk, respectively. For the measurement of LPO activity, milk was mixed with tetramethylbenzidine solution and incubated at 37°C for 30 min, followed by the measurement of optical density. When only milk with low SCC (132 ± 12 × 103 cells/mL) was used, a significant decrease in LPO activity was detected in primiparous cows from 0 to 4 mo postpartum. Lactoperoxidase activities of primiparous cows in mo 1, 2, and 3 postpartum were significantly higher than those in multiparous cows. When composite milk was divided based on LPO activity, the SCC was significantly higher in the groups with LPO activity >5 and from 3 to 3.9 U/mL in the second- and fourth-parity cows, respectively, compared with the group with LPO activity <2 U/mL. Extremely high SCC were found in the ≥fifth-parity cows, even in low-LPO activity groups. In the case of quarter milk, higher LPO activity was associated with increased SCC in all 3 cows. The percentage of quarter milk samples with high SCC (4,062 ± 415 × 103 cells/mL) increased with an increase in the LPO activity. The percentage of quarter milk samples with high SCC was 50.0 to 100% in the milk with LPO activity ≥5 U/mL. These results indicate that the correlation of LPO activity to the SCC in bovine milk may point to the potential use of the former as an indicator of SCC. 相似文献
59.
Kim J Yamasaki R Park J Jung H Lee H Kawai T 《Journal of Bioscience and Bioengineering》2004,97(2):138-140
Protein adsorption on a gold surface is investigated by comparing the results of quartz crystal microbalance method and atomic force microscopy. The adsorption of streptavidin on functional gold surfaces is directly monitored by a quartz crystal microbalance, and confirmed by atomic force microscopy. For this investigation, a modified gold substrate is fabricated to obtain a topographic image of streptavidin molecules. Both methods show a correlation in terms of the highly dense protein single-layer formation, and the modified gold electrode shows a slightly denser protein layer formation because of the difference in substrate geometry as compared with that of a mica surface. 相似文献
60.
DNA环介导等温扩增(LAMP)方法是一种新型的核酸扩增技术,该方法是在等温的条件下进行的,具有反应时间短、灵敏度高、特异性强的特点.本文以产麻痹性贝毒(PSP)的亚历山大藻为研究对象,采用简易法提取DNA模板,设计特异性LAMP引物,利用LAMP技术进行产毒藻种的快速检测,同时,着重对LAMP技术与PCR技术在检测微小亚历山大藻细胞的灵敏度方面做了比较.向LAMP终产物中加入SYBR Green I 染料后可直接用肉眼观察结果而不需要通过凝胶电泳来观察.结果表明,LAMP技术在恒温65℃,1h内就可以检测到产毒藻种;LAMP技术检测微小亚历山大藻的最低检测限为200个/ml,而PCR技术的最低检测限为1000个/ml,LAMP扩增方法比PCR扩增方法的程序简单、反应时间短、灵敏度高;LAMP技术不需要精密的温度循环装置,有恒温加热设备就可以满足检测条件,可用于野外检测. 相似文献