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An infinite plate with an asymmetric bilaterally-bent crack is analyzed as a bending problem of a thin plate. Stress distributions and stress intensity factors are obtained for some angles and length of bent crack. These are obtained for the some Poisson's ratio. Influence of the initial crack width on the stress intensity factor are also investigated. Three loading conditions are taken into consideration: uniform out of plane bending at infinity in the and directions and uniform out of plane twist. The rational mapping function in the form of a sum of fractional expressions and the complex variable method are used for the analysis. 相似文献
94.
95.
By use of carbon black containing quaternary ammonium carboxylate (COO?N+R4) groups as catalyst, the anionic ring opening polymerization of β-propiolactone (PL) was carried out at 50°C. Although carbon black itself was unable to initiate the polymerization of PL, carbon black containing COO?N+R4 groups, which was prepared by the reaction of carboxyl groups with corresponding quaternary ammonium hydroxide, was found to be able to initiate the polymerization. The carbon black obtained from the polymerization gave a stable colloidal dispersion in an organic solvent, and it was confirmed that the polyester formed was effectively grafted onto the surface. In addition, the effect of quaternary ammonium countercation on the polymerization was investigated. 相似文献
96.
In this study, we have carried out fundamental research on lubricant depletion due to laser heating in thermally assisted magnetic recording. In particular, we investigated the effects of lubricant film thickness and lubricant bonding ratio on lubricant depletion. Conventional lubricants Zdol2000 and Ztetraol2000 were used. The lubricant depletion characteristics due to laser heating were found to depend largely on the lubricant film thickness and material. That is, for films thicker than one monolayer, the lubricant depletion depth increased with the laser-irradiation duration, whereas the thickness of the lubricant after laser irradiation on the diamond-like carbon (DLC) films tended to remain at a constant film thickness of one monolayer. The lubricant depletion width gradually increased as the laser irradiation duration increased. The increasing trends for the lubricant depletion width were quantitatively very similar and almost independent of the initial lubricant film thickness. However, for lubricant films with thicknesses less than one monolayer, the lubricant depletion depth was very small. The lubricant depletion width increased remarkably to several hundred micrometers as the laser irradiation duration increased. The lubricant depletion depth and width were much smaller for Ztetraol2000 than Zdol2000. In addition, the lubricant-bonding ratio was found to greatly affect the lubricant depletion characteristics due to laser heating. In other words, the lubricant depletion depth and width decreased as the bonding ratio increased. The lubricant depletion mechanism involves the evaporation of mobile lubricant molecules when the maximum attained temperature is less than 100 °C. Another suggested lubricant depletion mechanism involves the thermocapillary stress effect, which is induced by the disk surface temperature gradient resulting from the non-uniformity of the laser spot intensity distribution. 相似文献
97.
Norio Sakai Hideki Horie Hiromasa Yanagisawa Tadashi Fujii Shinya Mizokami Koji Okamoto 《Journal of Nuclear Science and Technology》2014,51(7-8):951-963
The Modular Accident Analysis Program (MAAP) model enhancement items to improve the simulation capability for molten corium behavior in the accidents at the Fukushima Dai-ichi nuclear power plants were validated with the Phenomena Identification and Ranking Table (PIRT). The importance ranks of the identified phenomena were evaluated for each time phase through brainstorming and discussion with the experts in the Atomic Energy Society of Japan and the members of the MAAP model enhancement project. When the current MAAP evaluation models were reviewed with the PIRT, it is found that 95 of the 386 high-ranked phenomena were not considered in MAAP 5.0.1. While 62 of these phenomena will have been addressed in the MAAP enhancement project and 25 others are not suitable to be analyzed by MAAP, 8 important phenomena should be considered in post-MAAP enhancement project with additional experiments or fundamental studies. 相似文献
98.
Shuichi Nakamura Kengo Hyodo Yuko Nakamura Norio Shibata Takeshi Toru 《Advanced Synthesis \u0026amp; Catalysis》2008,350(10):1443-1448
Enantioselective Friedel–Crafts alkylations of a variety of indoles with ethyl 3,3,3‐trifluoropyruvate catalyzed by novel chiral m‐phenylenebis(imidazoline)‐copper(II) complexes or the bis(imidazoline)‐achiral acid combination afforded products with high enantioselectivity. Both enantiomers of indole derivatives can be prepared with high enantioselectivities by tuning the N‐substituents of the imidazoline. 相似文献
99.
Oya-Ito T Naitou H Masuda S Kinae N Ohashi N 《Molecular nutrition & food research》2008,52(3):360-369
Diabetic patients are prone to severe bacterial infections. The functional alterations of neutrophils by hyperglycemia are thought to be partially responsible for such infections. In this study, we investigated the functional changes of neutrophil-like differentiated cell lines (dHL-60, dTHP-1, and dNB-4) by treatment with 5.5 mM, 11 mM, or 35 mM of glucose. In dHL-60 cells, the incubation with high glucose (35 mM) resulted in the enhancement of cell aggregation, the suppression of cellular fragility, the induction of reactive-oxygen species (ROS) production by phorbol myristate acetate (PMA) stimulation, and the impairment of phagocytosis. In dTHP-1 cells, the treatment with higher glucose generated the suppression of cellular fragility and extremely impaired phagocytosis (by 35 mM), and induced ROS production due to PMA stimulation (by 11 mM). Furthermore, the higher glucose exposure to dNB-4 cells enlarged intracellular vacuoles (by 35 mM) and induced ROS production due to PMA stimulation (by 11 mM). Since the ROS generation of those cells was enhanced only after PMA stimulation under the higher glucose conditions, glucose may have a priming effect rather than a triggering effect. These extraordinary sensitivities caused by the higher glucose treatments may reflect the dysfunction or overactivation of neutrophils. 相似文献
100.
Tani Hiroshi Uesaraie Yuki Lu Renguo Koganezawa Shinji Tagawa Norio 《Microsystem Technologies》2018,24(11):4641-4648
Microsystem Technologies - In this study, the smear by the lubricant and siloxane pickup at the laser heating in the heat assisted magnetic recording (HAMR) was evaluated using our developed... 相似文献