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11.
E Kojima M Izumi T Tanabe M Matsuda T Shimizu A Murakami K Murakami 《Canadian Metallurgical Quarterly》1997,(37):171-172
The extent of genetic identity observed in the young individuals which were micropropagated from a single Eucalyptus individual was analyzed by using DNA-fingerprinting. Among 40,000 tissue-cultured-seedings of E.citriodora, 200 plants were randomly chosen so that each total DNA might be extracted from their leaves. Using these DNAs as template, PCR was performed with some primers we found in advance that leads polymorphism for DNA of E. citriodora. In this study, all over the 200 cases, the band pattern formed cDNA fragment on a gel after electrophoresis was the identical one mutually. 相似文献
12.
Satoshi Nishimura Zhi-Gang Zhang Ken-Ichiro Sugiyama Izumi Kinoshita 《Nuclear Engineering and Design》2007,237(23):2201-2209
In order to clarify the fragmentation mechanism of a metallic alloy (U–Pu–Zr) fuel on liquid phase formed by metallurgical reactions (liquefaction temperature = 650 °C), which is important in evaluating the sequence of core disruptive accidents for metallic fuel fast reactors, a series of experiments was carried out using molten aluminum (melting point = 660 °C) and sodium mainly under the condition that the boiling of sodium does not occur. When the instantaneous contact interface temperature (Ti) between molten aluminum drop and sodium is lower than the boiling point of sodium (Tc,bp), the molten aluminum drop can be fragmented and the mass median diameter (Dm) of aluminum fragments becomes small with increasing Ti. When Ti is roughly equivalent to or higher than Tc,bp, the fragmentation of aluminum drop is promoted by thermal interaction caused by the boiling of sodium on the surface of the drop. Furthermore, even under the condition that the boiling of sodium does not occur and the solid crust is formed on the surface of the drop, it is confirmed from an analytical evaluation that the thermal fragmentation of molten aluminum drop with solid crust has a potential to be caused by the transient pressurization within the melt confined by the crust. These results indicate the possibility that the metallic alloy fuel on liquid phase formed by the metallurgical reactions can be fragmented without occurring the boiling of sodium on the surface of the melt. 相似文献
13.
Shionyu-Mitsuyama Clara; Shirai Tsuyoshi; Ishida Hirokazu; Yamane Takashi 《Protein engineering, design & selection : PEDS》2003,16(7):467-478
A computer program system was developed to predict carbohydrate-bindingsites on three-dimensional (3D) protein structures. The programssearch for binding sites by referring to the empirical rulesderived from the known 3D structures of carbohydrateproteincomplexes. A total of 80 non-redundant carbohydrateproteincomplex structures were selected from the Protein Data Bankfor the empirical rule construction. The performance of theprediction system was tested on 50 known complex structuresto determine whether the system could detect the known bindingsites. The known monosaccharide-binding sites were detectedamong the best three predictions in 59% of the cases, whichcovered 69% of the polysaccharide-binding sites in the targetproteins, when the performance was evaluated by the overlapbetween residue patches of predicted and known binding sites. Received April 24, 2003; revised June 2, 2003; accepted June 10, 2003. 相似文献
14.
M Ikeda K Noda M Hiura T Tamaya M Ozaki M Hatae M Ozawa T Yamabe K Tanaka R Izumi H Okada Y Ogita H Hoshiai 《Canadian Metallurgical Quarterly》1998,25(14):2249-2257
We conducted a multi-site late phase II trial of oral etoposide administered for 21 consecutive days in patients with cervical cancer in cooperation with 32 institutes. Fifty mg/body of oral etoposide was administered daily for 21 consecutive days. Treatment cycles were to be repeated at 4- to 5-week intervals. Eighty patients were enrolled and 70 patients were evaluated. The overall response rate (95% CI), including one complete response patient and 18 partial response patients, was 27.1% (19/70). The most commonly observed toxicity was myelosuppression such as leukopenia, neutropenia, hemoglobin decrease and thrombocytopenia. Other adverse effects were gastrointestinal toxicities such as anorexia, nausea, stomatitis and vomiting, as well as fatigue and alopecia. These adverse effects were well tolerated and controlled with medications. From these results we concluded oral etoposide administered for 21 consecutive days was an effective drug against cervical cancer. 相似文献
15.
Various aspects of our communication are well known to have changed over time (1-3). This article describes a cross-sectional study that examined the acoustic characteristics of two groups of Australian women aged 18-25 years from recordings made in 1945 and 1993 and investigated the possible changes in the voice across generations. Archival recordings from 1945 which had been used in a longitudinal study (4) were compared to recordings made in 1993. The results of this study show that women in 1993 have significantly deeper voices than women of the same age recorded in 1945. The possible factors influencing this change are discussed. 相似文献
16.
Tensile properties and plastic deformation modes of zirconium-niobium alloys were investigated at 290 and 77 K in the wide composition range from metastable to stable phase. Three types of plastic deformation modes, {332}113 twinning, {112}111 twinning and slip, were observed depending on alloy composition and temperature. {332}113 twinning, which occurs in metastable zirconium alloys, is related to the stability of phase to decomposition and leads to low yield stress and large elongation. On the other hand, {112}111 twinning, which appears in stable zirconium alloys, results from high critical stress for slip due to solution hardening and high Peierls stress and does not affect tensile properties significantly. The results obtained for zirconium-alloys are similar to those for titanium alloys, strongly suggesting that {332}113 twinning is an important plastic deformation mode which is common to phase alloys containing athermal phase. 相似文献
17.
The effects of temperature and grain size on the deformation and fracture behaviour of recrystallized Ni3Al doped with boron were investigated by tensile tests at temperatures up to 973 K as a function of grain sizes from 1.6 to 105m. The yield stress showed a positive temperature dependence to a peak temperature in somewhat different manners depending on the grain size. For coarse-grained specimens, a rapid drop in elongation was observed with increasing temperature. The predominant fracture mode changed with temperature from the transgranular fracture of {1 1 1} cracking to brittle intergranular fracture. This embrittlement at elevated temperatures was considered to occur by a high stress concentration at grain boundaries arising from increased flow stress level and the occurrence of grain boundary sliding (GBS). In contrast, the elongation was not so markedly decreased with temperature for intermediate- and fine-grained specimens which exhibited ductile intergranular fracture and cavitation fracture, respectively, at elevated temperatures, and a slant-type fracture and cup-cone fracture, respectively, at low temperatures. The suppression of serious high-temperature embrittlement for intermediate-grained specimens was explained in terms of the slow propagation of a crack formed by GBS, owing to stress relaxation by dynamic recrystallization (DR) and plastic deformation. In the case of ultra-fine-grained specimens a large elongation was developed at elevated temperatures, which was interpreted as that the further occurrence of DR with increasing volume fraction of grain boundaries reduces the cavitation promoted by GBS, and that the limited sliding length due to extremely small grain diameter raises the stress for cavity formation. 相似文献
18.
19.
Tomoshi Takahashi Michitomo Kato Yoritoshi Minamino Toshimi Yamane 《Journal of Materials Science》1987,22(9):3194-3202
The interdiffusion coefficients in the f c c phase of Cu-Zn-Sn alloys,
, have been determined at 1073 K. The concentration profiles indicate that the diffusion rate of tin is greater than that of zinc in the Cu-Zn-Sn alloy. The diffusion paths show the typical S-shaped curves. All of the four interdiffusion coefficients are positive and they are very sensitive to the solute concentration. The atomic mobilities of the three diffusing elements in Kirkendall planes increase in the order of Cu, Zn, Sn. The interaction energy of the Cu-Sn bond is much larger than that of the Zn-Sn bond. From the results of the present work it seems that the Onsager reciprocal relation holds in the a phase of the Cu-Zn-Sn system. 相似文献
20.
Upon the application of amperometric biosensor to the biological fluid, ascorbic acid interferes the amperometric determination of analytes, because the oxidative potential of ascorbic acid is lower than that of electro active substances such as H2O2 produced by the enzymatic reaction. In this study we propose a method to block ascorbic acid based on the electrostatic interaction with self-assembled monolayer (SAM) and its application of the surface modified electrode to biosensor. In order to form SAM on the gold electrode with carboxyl group, 7-carboxy-heptanethiol (7-CHT) was used. The 7-CHT modified electrode did not show anodic response to ascorbic acid, but oxidized phenanthroline cobalt complex [Co(phen)32+], which can be used as a mediator of biosensor. Thus, the 7CHT-modified electrode was applied to biosensor mediated with Co(phen)32+. Fructose dehydrogenase (FDH) was immobilized to the 7-CHT modified electrode. Fructose was determined selectively with the FDH/7-CHT modified electrode at the range of 0.2-2 mM. 相似文献