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111.
Prevention of catalyst deactivation in carbon monoxide methanation on a highly active Ni-based composite catalyst has been investigated. The composite catalyst, Ni-La2O3-Ru supported on silica, has greater activity than that of a Ni catalyst, but the decrease of the catalyst activity with reaction time is greater than that of the Ni catalyst, especially when the CO conversion is low. The reason for this behaviour is found in the relation between the amount of surface-carbon species and the degree of deactivation. When the CO methanation reaction is operated at above the temperature of complete CO conversion, catalyst deactivation is avoided. At such high temperatures the amount of surface-carbon species is small. The catalyst deactivation is considerably suppressed with a low concentration, e.g. 1–3 kPa, of additional CO2 or CO2 + H2O. The cause of this suppression is considered to be the renewal of the covered surface with the carbon-species by the competitive adsorption of these additives. 相似文献
112.
Itoh H Iwasaki M Nakajima Y Endo Y Hanaoka T Sasaki H Tanaka T Yang B Tsugane S 《The Science of the total environment》2008,402(2-3):171-175
Cadmium may act like an estrogen and be a potential risk factor for estrogen-related diseases such as breast cancer and endometriosis. Here, we tested the hypothesis that higher cadmium exposure is associated with endometriosis among infertile Japanese women in a hospital-based case-control study. We recruited consecutive female patients aged 20-45 years who had complained of infertility and presented to a university hospital in Tokyo. The subjects were interviewed and provided a urine sample prior to a laparoscopic diagnosis of endometriosis between January 2000 and December 2001. The severity of endometriosis was then dichotomized into controls (stage 0 and I) and cases (stage II-IV). We finally measured urinary total cadmium concentration in 54 cases and 74 controls as a biomarker of long-term cumulative exposure. Odds ratios were adjusted for average menstrual cycle length, body-mass index and smoking status using unconditional logistic regression. Results showed no association between endometriosis and urinary cadmium concentration. Medians (interquartile ranges) of urinary cadmium concentration in cases and controls were 0.53 (0.40-0.73) and 0.54 (0.34-0.76) microg/g creatinine, respectively (P for difference=0.88). Adjusted odds ratio (95% confidence interval) for the highest versus lowest tertile of urinary creatinine-adjusted cadmium concentration was 0.86 (0.30 to 2.49, P for trend=0.79). Our results do not support the hypothesis that higher urinary cadmium concentration is associated with the risk of endometriosis. 相似文献
113.
Ito T Fujimura S Uchino M Tanaka N Matsufuji Y Miyaji T Takano K Nakagawa T Tomizuka N 《Yeast (Chichester, England)》2007,24(6):523-532
In this study, we attempted to classify the methylotrophic yeasts based on diversities of alcohol oxidase (AOD), i.e. zymogram patterns and partial amino acid sequences. According to zymogram patterns for AOD, members of the methylotrophic yeasts separate into two major lineages, one group involving strains having a single AOD and the other group, including Pichia methanolica, Candida pignaliae and C. sonorensis, showing nine AOD isozymes. Based on partial amino acid sequences of AOD, the methylotrophic yeasts could be divided into five groups, and this classification agrees mostly with grouping based on 26S domain D1/D2 rDNA nucleotide sequences, except for some strains. Moreover, the strains having AOD isozymes constitute one group with P. trehalophila, P. glucozyma and Pichia sp. strain BZ159, although these strains are divided into two types, based on amino acid sequences of second AODs. On the other hand, these AOD isozymes consist of two subunits; the first subunits are induced not only by methanol but also by glycerol and pectin, although the second subunits are mainly induced by methanol. These data indicate that AOD isozymes and second AOD genes distribute widely in several methylotrophic yeasts in the natural environment, and second AOD genes may have evolved as methylotrophic genes that can adapt to the environmental conditions of higher methanol concentrations. 相似文献
114.
Masanobu Yoshida Toshihiro Takahashi Masayuki Hikita Hiroyuki Watanabe Naomi Hashimoto Hitoshi Okubo 《Electrical Engineering in Japan》1999,129(4):58-65
We observed current pulse waveforms of partial discharge (PD) in SF6 gas so as to investigate the PD mechanism. We also measured light intensity and light emission image of PD simultaneously under different conditions of applies voltage and SF6 gas pressure. From these experiments, we found that the “double-peak current waveform” appeared at high pressure and high voltage conditions. We also analyzed the mutual correlation of waveforms between a single current and the light emission. Moreover, we obtained experimental evidence of filmentlike light image appearing at the PD tip under the same condition with double-peak current waveform. From the electric field analysis around the needle electrode tip, we believe that the filamentlike light image expands beyond the critical electric field of SF6 gas. Thus, we concluded that these current waveforms with double peaks showed evidence of leader-type PD, leading to breakdown. Finally, we could point out that leader-type PD should be distinguished and measured for the diagnosis of GIS insulation performance. © 1999 Scripta Technica, Electr Eng Jpn, 129(4): 58–65, 1999 相似文献
115.
This paper describes a transient cooling technology for electronic equipments using phase-change material (PCM). The module is made of low-cost materials, yet it is designed to achieve a reasonably high level of heat transfer performance. Paraffin is used as the PCM. In previous our report, we can estimate the cooling performance of PCM by using a thermal network method, which cannot calculate melted PCM flow. In this paper, we consider the heat transfer phenomena of PCM module more deeply by using computational fluid dynamics (CFD) analysis with an enthalpy porosity method. By using this method, we can calculate phase-change phenomena and flow phenomena of melted PCM with CFD analysis. First, we briefly explain the results of the experiment and the thermal network analysis. Then we describe the details of CFD analysis with the enthalpy porosity method. In this calculation, melted PCM flow and heat absorption of latent heat can be analyzed. Therefore, we can discuss the reason why the thermal network analysis can estimate cooling performance of PCM module without dealing with melted PCM flow. The calculation results showed that natural convective flow of melted PCM affects the cooling performance of the PCM module. In the case where the PCM module is set vertically, high temperature and low temperature locations exist on the substrate. If several devices are cooled with the PCM module, device consuming the most power must be set in the lower part of the PCM module. From these results, we can conclude that no natural convective flow occurs in our experiment due to the shape of the PCM module. 相似文献
116.
Hyunjae Lee Sunghoon Lee Wonryung Lee Tomoyuki Yokota Kenjiro Fukuda Takao Someya 《Advanced functional materials》2019,29(48)
Skin‐based electrical‐signal monitoring is one of the basic and noninvasive diagnostic methods for observing vital signals that contain valuable information about the dynamic status of the inner body. Soft bioelectronic devices are developed for the acquisition of high‐quality biosignals by taking advantage of their inherent thin and soft bodies. Among these devices, the organic electrochemical transistor (OECT) is a promising local transducing amplifier because of its key advantages, such as low operating voltage, high transconductance, and biocompatibility. However, the transistor's direct electrolyte‐gated operation limits its ability to measure biosignals only when the electrolyte exists. Here, an ultrathin OECT‐based wearable electrophysiological sensor based on a thin (≈6 µm) and nonvolatile gel electrolyte is reported, which can operate on dry biological surfaces. This sensor can measure biopotentials with a high mechanical stability and high signal‐to‐noise ratio (24 dB) even from dry surfaces of the human body and also shows stable performance during long‐term continuous monitoring and multiple reuse in a test that lasted more than a week. 相似文献
117.
Trans‐fatty acid promotes thrombus formation in mice by aggravating antithrombogenic endothelial functions via Toll‐like receptors 下载免费PDF全文
Kensuke Kondo Tatsuro Ishida Tomoyuki Yasuda Hideto Nakajima Kenta Mori Nobuaki Tanaka Takeshige Mori Tomoko Monguchi Masakazu Shinohara Yasuhiro Irino Ryuji Toh Yoshiyuki Rikitake Kazunobu Kiyomizu Yoshiaki Tomiyama Junichiro Yamamoto Ken‐ichi Hirata 《Molecular nutrition & food research》2015,59(4):729-740
118.
Implementation of a decision support system using an interactive large-scale high-resolution display
Tomoyuki Ishida Yusuke Hirohara Nobuyuki Kukimoto Yoshitaka Shibata 《Artificial Life and Robotics》2017,22(3):385-390
In this research, we propose and evaluate a decision support system using an interactive large-scale high-resolution display. This decision support system supports the summarization and decision-making of a large amount of disaster information during the occurrence of a large-scale natural disaster. Municipal employees at the disaster control headquarters can display disaster information on the large-scale display with a touch or flick on a laptop or tablet. To evaluate the operability, readability, functionality, and necessity of the decision support system, we surveyed 23 municipal employees in the disaster prevention division using a questionnaire. The system received a great evaluation in all the evaluation items. 相似文献
119.
Tomoyuki Hoshino 《Microscopy research and technique》1990,15(2):104-114
The cochleas of four human fetuses ranging 22–25 weeks gestation were studied by scanning electron microscopy (SEM) for the purpose of obtaining a better understanding of the nerve fiber arrangement in the human ear. After critical point drying, the specimens were dissected and the floor of the tunnel of Corti and the outer wall of Nuel's space were exposed for observation. Upper cochlear turns, especially the apical turn, seemed to be still immature. Observed nerve fibers were classified into three types:
- 1 Spiral fibers: Fibers traveling basalward and following the shape of the cochlea were found in both the tunnel of Corti and Nuel's space and believed to be the afferent nerves responsible for innervating the outer hair cells
- 2 Radial fibers: radiating outward from the osseous spiral lamina—one such radial fiber transversing high in the tunnel space (supposedly the efferent nerve servicing the outer hair cells), and another sort of radial fiber (found crossing the tunnel floor), the nature of which was uncertain.
- 3 Irregular fibers: Consisting of thin, randomly running fibers within the cochlea. The destination of these fibers was not determined, but possibly they represent transitory nerve branchings of afferent or more probably efferent nerves, which would later regress during maturation.
120.
The statistical information processing can be characterized by the likelihood function defined by giving an explicit form
for an approximation to the true distribution. This mathematical representation, which is usually called a model, is built
based on not only the current data but also prior knowledge on the object and the objective of the analysis. Akaike2,3) showed that the log-likelihood can be considered as an estimate of the Kullback-Leibler (K-L) information which measures
the similarity between the predictive distribution of the model and the true distribution. Akaike information criterion (AIC)
is an estimate of the K-L information and makes it possible to evaluate and compare the goodness of many models objectively.
In consequence, the minimum AIC procedure allows us to develop automatic modeling and signal extraction procedures. In this
article, we give a simple explanation of statistical modeling based on the AIC and demonstrate four examples of applying the
minimum AIC procedure to an automatic transaction of signals observed in the earth sciences.
Genshiro, Kitagawa, Ph.D.: He is a Professor in the Department of Prediction and Control at the Institute of Statistical Mathematics. He is currently
Deputy Director of the Institute of Statistical Mathematics and Professor of Statistical Science at the Graduate University
for Advanced Study. He obtained his Ph.D. from the Kyushu University in 1983. His primary research interests are in time series
analysis, non-Gaussian nonlinear filtering, and statistical modeling. He has published over 50 research papers. He was awarded
the 2nd Japan Statistical Society Prize in 1997.
Tomoyuki Higuchi, Ph.D.: He is an Associate Professor in the Department of Prediction and Control at the Institute of Statistical Mathematics. He
is currently an Associate Professor of Statistical Science at the Graduate University for Advanced Study. He obtained his
Ph.D. from the University of Tokyo in 1989. His research interests are in statistical modeling of space-time data, stochastic
optimization techniques, and data mining. He has published over 30 research papers. 相似文献