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11.
A constitutive equation taking into account corner formation on the yield surface and the Bauschinger effect is developed. The behaviour of circular long tubes subjected to external pressure and axial load under plane strain and generalized plane-strain conditions are analyzed in conjunction with the proposed constitutive equation. The influence of axial load, the Bauschinger effect and corner formation, including the corner angle, and the mobility of the corner axis to the direction of stress history upon such global deformation behaviour as maximum pressure, pressure vs displacement relation and axial strain, are clarified. With regard to local deformation, these effects on the strain rate and strain localization, surface unevenness and shear band formation from the highly strained internal surface are investigated. 相似文献
12.
Following a linear theory of magneto-thermo-elasticity with thermal relaxation, the propagation of Rayleigh waves in a semi-infinite body permeated by an uniform magnetostatic field parallel to the boundary surface is investigated. It is assumed that the elastic medium under consideration is a homogeneous, isotropic, electrically and thermally conducting one. The roots of the frequency equation are calculated numerically. The approximate solution for small thermoelastic and magnetoelastic coupling is obtained and compared with the exact solution. 相似文献
13.
The primary objective of this paper is to study the influence of the electroelastic interactions on the stress intensity factor
in bonded layers of piezoelectric and orthotropic materials containing a crack along the interface under antiplane shear.
Attention is given to a two-layer hybrid laminate formed by adding a layer of piezoelectric ceramic to a unidirectional graphite/epoxy
composite or an aluminum layer. Electric displacement or electric field is prescribed on the surfaces of the piezoelectric
layer. The problem is formulated in terms of a singular integral equation which is solved by using a relatively simple and
efficient technique. A number of examples are given for various material combinations. The results show that the effect of
the electroelastic interactions on the stress intensity factor and the energy release rate can be highly significant.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
14.
Junko Shindo 《Nutrient Cycling in Agroecosystems》2012,94(1):47-61
Gross and per unit agricultural land area nitrogen balance (NB G and NB A, respectively) in agricultural areas were estimated with a nitrogen-flow model for 13 Asian countries, for regions within a country, and for individual grid cells, from 1970 to 2005. Country- and regional-level estimates showed that NB A is higher in Japan and South Korea than in other Asian countries, but has recently been stable or decreasing. The contribution of inorganic fertilizer to the nitrogen input is decreasing, whereas that of livestock manure is increasing in these countries. In many other countries, the primary nitrogen source is inorganic fertilizer and its input rate and NB A have increased sharply since the 1980s. NB A of some Chinese provinces and Indian states were as high as those of Japan and South Korea. The results suggest that regional-scale estimation is necessary because of the large spatial variability in nitrogen flows within a country. Based on the NB G estimated for each 0.5°?×?0.5° grid cell, nitrogen outflow from agriculture into major river basins was evaluated. About 20?% of the nitrogen balance flowed into China??s Changjiang River basin, versus 10?% into the Ganges River basin. Uncertainties in the basic data and estimation results, and the use of an alternative measure of a country??s environmental performance were discussed. 相似文献
15.
Hyun Soon Park Yasukazu Murakami Keiichi Yanagisawa Tsuyoshi Matsuda Ryosuke Kainuma Daisuke Shindo Akira Tonomura 《Advanced functional materials》2012,22(16):3434-3437
Peculiar magnetic domain walls produced in Heusler alloys, which have attracted renewed interest due to their potential application to actuators and spintronic devices, are studied here using electron holography. The observations reveal unexpectedly narrow magnetic domain walls, the width of which showed perfect agreement with that of the antiphase boundaries (APB, e.g., only 3 nm). While the results can be explained by the significant depression of ferromagnetism due to the local chemical disorder, the electron phase shift indicates that ferromagnetic correlation still remains in the APB region. 相似文献
16.
Naohiro Gotoh Shino Miyake Hiroko Takei Kumi Sasaki Saori Okuda Michitaka Ishinaga Shun Wada 《Food Analytical Methods》2011,4(4):525-530
We developed a simple method for quantification of the peroxide value (PV) in colored lipids on the basis of the reaction
between triphenylphosphine (TPP) and oxidized oil to afford triphenylphosphineoxide (TPPO). Diphenylphosphineoxide (DPPO)
was employed as internal standard. The formed TPPO was analyzed by high-pressure liquid chromatography–UV spectroscopy with
absorption at 260 nm. The conditions that gave the highest correlative calibration curve between the peak area on the chromatogram
and peroxide value were identified: the optimum TPP–oxidized oil mix ratio, reaction temperature, and reaction time were found
to be 2:1, 40 °C, and 30 min, respectively. Linear calibration curves, passing through the origin, were obtained for PV versus
TPPO and TPPO versus DPPO. The quantification limit for this method was 2.01 pmol hydroperoxyl group, which corresponds to
a PV value of 0.2 meq/kg in a 10-mg oil sample. This method was used to measure the PV in colored fats and oils or lipids
extracted from dark meat and processed food containing a coloring agent. Though the official method could not measure the
PVs in the colored lipids, the method proposed here, which uses an inexpensive chemical reagent and machine, could. The developed
method could play an important role for food quality control. 相似文献
17.
Tetsuo Suga Yasuoa Murai Taizo Kobashi Kunika Ueno Minoru Shindo Katsunori Kanno 《Welding International》2016,30(3):166-174
In many industries, there are applications that require the joining of stainless steel and copper components; therefore, the welding of dissimilar stainless steel/copper joints is a common process. For this investigation, the optimal brazing conditions and suitable filler metals for laser brazing of stainless steel/copper lap joints were studied. Tensile shear force increases with increases in the laser spot diameter or in the laser irradiation angle, which is associated with increased bonding width; however, as bonding width approaches 2 mm, tensile shear force reaches a saturated value due to fracturing at the HAZ of the Cu base plate. In order to obtain joints with high tensile shear strength, laser brazing was optimized by using Cu–Si-based filler metal under the following conditions: laser power, 4 kW; spot diameter, 3 mm; laser irradiation angle, 80°; irradiation position shift, 0.6 mm; brazing speed, 0.30 m/min; and filler metal feed speed, 0.30 min. Concerning filler metals, it was found that the Ni–Cu type showed relatively large tensile shear force even at high welding speeds in comparison with those of the Cu–Si, Cu, Cu–Ni, Ni–Cu and Ni types, respectively. 相似文献
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