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1.
Tatsuo Inoue Nobutada Ohno Akihiko Suzuki Toshihide Igari 《Nuclear Engineering and Design》1989,114(3)
Uniaxial tests to identify plasticity-creep interaction in
steel at 600°C were carried out as the Benchmark Project by the Subcommittee on Inelastic Analysis and Life Prediction, JSMS. The purpose of this paper is to present recent experimental data and predictions of constitutive models obtained in the project. Ten types of constitutive models were utilized to compare analytical predictions to sixteen benchmark experiments which are grouped into four categories: (I) tensile and creep tests under monotonic loading, (II) mixed mode tests under plastic and creep loading, (III) ratcheting deformation tests under program loads, and (IV) cyclic deformation tests under the combination of different strain rates. The benchmark tests in Group IV are used to estimate the creep-fatigue life of
steel; the results will be published in a separate paper. 相似文献
2.
Persistence of the hypoglossal artery is an unusual congenital abnormality of the carotid arterial system, and the simultaneous occurrence of atheromatous disease in the internal carotid artery and persistent hypoglossal artery is even more uncommon. Carotid surgery in this situation is challenging, and the surgeon must be aware of potential inherent pitfalls. A 74-year-old woman with asymptomatic stenosis of both internal carotid and hypoglossal arteries associated with occlusion of the contralateral internal carotid artery underwent successful revascularization. The anatomy of this unusual lesion and the surgical strategies, which included cranial nerve dissection and mandibular subluxation, are reviewed. 相似文献
3.
4.
H Saitoh T Ono A Nomura Y Iwasaki N Ohno S Matsumoto Y Kobayashi H Atarashi T Katoh H Kishida H Hayakawa 《Canadian Metallurgical Quarterly》1998,46(10):1043-1048
Although diagnosis of neurally mediated syncope (NMS) using head-up tilt (HUT) test has been established, the exact mechanism of NMS has not yet been elucidated. We evaluated beta and alpha-adrenergic function in NMS patients by pharmacological autonomic function test. The alpha-adrenergic sensitivity of NMS patients was significantly lower than that of control subjects. The patients who need low dose isoproterenol for provocation of syncope showed higher beta-adrenergic sensitivity than patients who developed syncope without isoproterenol. Thus, pharmacological autonomic function test was useful for evaluation of NMS patients. 相似文献
5.
We investigated the mechanisms of renal vascular wall thickening in a rat model of N-nitro L-arginine methyl ester (L-NAME)-induced hypertension. To separate the effects of L-NAME-induced hypertension from other effects of nitric oxide (NO) inhibition, we created two models of L-NAME-induced hypertension: both had the same blood pressure level but NO inhibition was moderate in one group (group M) and severe in the other (group S). Urinary excretion of nitrates and nitrites was lower in group S than in group M. Wall thickening and lipid deposition in renal vessels were significantly greater in group S than in groups M. Simple and multiple regression analyses indicated that renal vascular wall thickening was more strongly correlated with lipid deposition than with blood pressure. The number of vessels positive for staining with Sudan black B was negatively correlated with urinary NO excretion. Expression of fibronectin and transforming growth factor-beta was greater in the Sudan black B-positive than in the Sudan black B-negative vessels, suggesting that extracellular matrix production was increased in vessels with lipid deposition. Lipid deposition and increased production of extracellular matrix may contribute to renal vascular wall thickening in L-NAME-induced hypertension. Some mechanisms independent of hypertension play important roles in vascular wall thickening induced by NO inhibition. 相似文献
6.
In an assembly line of a just-in-time (JIT) production system, workers have the power and the responsibility to stop the line when they fail to complete their operations within their work zones. This paper deals with a sequencing problem for the mixed-model assembly conveyor line in the JIT production system. In some environment, the most important criterion is the line stoppage rather than the variation of production rates. The problem is to find an optimal sequence of units that minimizes the total line stoppage time. Lower and upper bounds of the total line stoppage time are derived and the branch-and-bound method is applied to the problem. A numerical example is given. 相似文献
7.
Active 4-dodecanoyl-2-nitrophenyl esters of β-alanine, β-alanyl-β-alanine, and β-alanyl-β-alanyl-β-alanine were prepared, and tried to polymerize in various solvents. Nonpolar solvents were found to be convenient for the polycondensation reaction. The yield of the polycondensation was high for the monopeptide ester, and less for the dipeptide and tripeptide esters. The effect of temperature on the polycondensation reaction was also studied. 相似文献
8.
Several onium cations having vinyl group formed ionic liquids after coupling with bis(trifluoromethanesulfonyl)imide. These monomers were polymerized, and the relation between onium cation structure and properties of thus polymerized ionic liquids was investigated. The polymerized ionic liquid having ethylimiadzolium cation unit showed the highest ionic conductivity of around 10−4 S cm−1 at 30 °C among the obtained polymers reflecting the lowest glass transition temperature of −59 °C. These polymers were thermally stable and their decomposition temperatures were about 350 °C. The ionic conductivity of the polymerized ionic liquids decreased by both the addition of lithium bis(trifluoromethanesulfonyl)imide and the polymerization in the presence of cross-linker. However, the polymerized ionic liquid having 1-methylpiperidinium cation structure showed good lithium ion transference number of 0.43 at room temperature. 相似文献
9.
Summary Giant hybrid liposomes of polymerizable lipid and cholesterol were prepared by the hydration method and were polymerized by UV irradiation. The obtained giant liposomes were freeze-dried and washed with chloroform to skeletonize the frame structure of the polymerized membrane. The skeletonized liposomes were directly confirmed by scanning electron microscopy. The single-layered and fully spherical liposome frame were easily confirmed by the stereo-pair of the obtained micrographs. 相似文献
10.
The oxidative coupling of methane has been tested over alkali- and alkaline earth-phosphate catalysts at 700 and 775 °C with and without the introduction of a small quantity of tetrachloromethane (TCM) to the feedstream. In general, the conversion of methane was enhanced by the addition of TCM but the effect on selectivity was dependent on the catalyst being examined. The selectivity to C2 and higher hydrocarbons and that to oxidation products have been shown to have a dependence on the cation radius/charge ratio. 相似文献