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991.
Yu You Mikako Kato Makoto Ohtsuka Hiroyuki Fukuyama 《Journal of the American Ceramic Society》2013,96(10):3054-3060
The effects of ZrO2 additions to Al2O3 were investigated to improve the evaporation rate of Al2O3 for bulk AlN crystal growth. The evaporation rate of Al2O3 increased concomitantly with increasing ZrO2 concentration under a nitrogen gas stream at 2223 K. The ZrO2 was predominantly nitrided. The nitridation of ZrO2 kept the local oxygen partial pressure high at the pellet surface, which suppressed the nitridation of Al2O3. The nitridation of ZrO2 caused the outward diffusion of ZrO2 (Zr4+ and O2?) in the pellet, which was accelerated further by the presence of Al2O3–ZrO2 liquid phase in grain boundaries, leading to the prompt formation of ZrN porous layer on the pellet surface. The suppressed nitridation of Al2O3 and the formation of porous ZrN layer were the reasons for the enhanced evaporation of Al2O3, leading to enhanced bulk AlN growth. 相似文献
992.
Makoto Souwa Daichi Yamazaki Michio Okada Akitaka Yoshigoe Yuden Teraoka Toshio Kasai 《Electrical Engineering in Japan》2011,175(4):43-47
We report the results of a study of the natural oxidation of Cu3Au(110) with high‐resolution X‐ray photoemission spectroscopy in conjunction with synchrotron radiation. The clean surface of Cu3Au(110) is terminated with 50% Au and 50% Cu atoms. After natural oxidation in the air, Cu atoms segregate on the surface and produce Cu‐oxide. As a result, Au atoms move into the bulk. Au atoms below the oxide reduce the diffusion of O atoms farther into bulk and limit the oxide thickness. The face dependence of natural oxidation indicates that the diffusion of Cu atoms also contributes to oxide formation. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 175(4): 43–47, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21149 相似文献
993.
Evidence for Charge‐Trapping Inducing Polymorphic Structural‐Phase Transition in Pentacene
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994.
Takao Ito Seigo Matsuno Zengyu Xia Makoto Sakamoto Rajiv Mehta 《Artificial Life and Robotics》2010,15(3):249-252
In a keiretsu, i.e., a set of companies with interlocking business relationships, it is important for corporate management to identify
those companies over which they reciprocally exercise greater influence and power. In this article we employ a DEcision MAking
Trial and Evaluation Laboratory (DEMATEL) to illustrate the reciprocal influence of each company in Mazda’s Yokokai keiretsu, as measured by the number of transactions and cross-shareholdings. Furthermore, we calculate the centrality index of each
company, and then analyze the relationship between centrality index and influence in order to identify the determinants of
the influence. Based on the findings, we identify some characteristics of effective relationships which have important managerial
implications. 相似文献
995.
996.
997.
The diffusion coefficients of pullulan added in gellan gum solutions as a probe polymer were measured using pulsed-field-gradient stimulated-spin-echo (PFG-Ste) 1H NMR in order to investigate the gelation mechanism and gel structure. The echo intensity of gellan was steeply decreased at around the gelling temperature Tgel indicating stiffening of the gellan chains upon aggregation and formation of the network. The diffusion coefficient of pullulan Dpull increased with decreasing temperature below Tgel. This result suggests that the decrease in concentration of solute gellan in the interspaces of the network below Tgel, as evidenced by the decrease in its echo intensity, leads to an overall decrease of hydrodynamic interactions between gellan and pullulan. The characteristic hydrodynamic shielding length ξ was calculated from the relation Dpull/Dpull,0 = exp(−Rh/ξ), where Dpull,0 is Dpull in dilute solution and Rh is the hydrodynamic radius of pullulan. The temperature dependence of ξ, which was investigated for varying concentrations of several cations, was found to follow closely the gelling temperature, and in particular, showing a very similar thermal hysteresis. 相似文献
998.
Yasuhiro Teranishi Hiroshi Kuwahara Masaru Ueda Tadashi Takemura Masanori Kusumoto Keiji Nakamura Jun Sakai Toru Kimura Yasuji Furutani Makoto Kawashima Genji Imokawa Mari Nogami-Itoh 《International journal of molecular sciences》2020,21(22)
A ceramide deficiency in the stratum corneum (SC) is an essential etiologic factor for the dry and barrier-disrupted skin of patients with atopic dermatitis (AD). Previously, we reported that sphingomyelin (SM) deacylase, which hydrolyzes SM and glucosylceramide at the acyl site to yield their lysoforms sphingosylphosphorylcholine (SPC) and glucosylsphingosine, respectively, instead of ceramide and/or acylceramide, is over-expressed in AD skin and results in a ceramide deficiency. Although the enzymatic properties of SM deacylase have been clarified, the enzyme itself remains unidentified. In this study, we purified and characterized SM deacylase from rat skin. The activities of SM deacylase and acid ceramidase (aCDase) were measured using SM and ceramide as substrates by tandem mass spectrometry by monitoring the production of SPC and sphingosine, respectively. Levels of SM deacylase activity from various rat organs were higher in the order of skin > lung > heart. By successive chromatography using Phenyl-5PW, Rotofor, SP-Sepharose, Superdex 200 and Shodex RP18-415, SM deacylase was purified to homogeneity with a single band of an apparent molecular mass of 43 kDa with an enrichment of > 14,000-fold. Analysis by MALDI-TOF MS/MS using a protein spot with SM deacylase activity separated by 2D-SDS-PAGE allowed its amino acid sequence to be determined and identified as the β-subunit of aCDase, which consists of α- and β-subunits linked by amino bonds and a single S-S bond. Western blotting of samples treated with 2-mercaptoethanol revealed that, whereas recombinant human aCDase was recognized by antibodies to the α-subunit at ~56 kDa and ~13 kDa and the β-subunit at ~43 kDa, the purified SM deacylase was detectable only by the antibody to the β-subunit at ~43 kDa. Breaking the S-S bond of recombinant human aCDase with dithiothreitol elicited the activity of SM deacylase with ~40 kDa upon gel chromatography. These results provide new insights into the essential role of SM deacylase expressed as an aCDase-degrading β-subunit that evokes the ceramide deficiency in AD skin. 相似文献
999.
1000.
Makoto Fujie Hirofumi TakamotoTakeru Kawasaki Akiko FujiwaraTakashi Yamada 《Journal of Bioscience and Bioengineering》2010,109(2):153-158
We monitored growth and movement of Ralstonia solanacearum harboring the plasmid pRSS12 in tomato seedlings. The plasmid contains a gene for green fluorescent protein (GFP) and is stably maintained in R. solanacearum cells without selection pressure. Bacteria harboring the plasmid can be tracked in planta by visualizing GFP fluorescence. Stems of seedlings were infected with R. solanacearum cells transformed with pRSS12, and bacterial growth and movement, particularly around the vascular bundles, were monitored for more than 7 days. Our results showed that vascular bundles are independent of each other within the stem, and that it takes a long time for R. solanacearum cells to migrate from one vascular bundle to another. For real-time monitoring of bacteria in planta, tomato seedlings were grown on agar medium and bacterial suspension was applied to the root apex. The bacterial invasion process was monitored by fluorescent microscopy. Bacteria invaded taproots within 6 h, and movement of the bacteria was observed until 144 h after inoculation. In susceptible tomato cultivars, strong GFP fluorescence was observed in hypocotyls and lateral roots as well as the taproot. In resistant cultivars, however, GFP fluorescence was rarely observed on lateral roots. Our results show that this monitoring system can be used to assess bacterial pathogenicity efficiently. 相似文献