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71.
72.
The effects of the stress intensity factor and dissolved hydrogen on the crack growth rate in primary water reactor environments
was investigated with alloy 600 with continuous carbide films at grain boundaries. A primary water stress corrosion cracking
of intergranular fracture mode was observed. The intergranular crack growth rate decreased with a decreasing stress intensity
factor, and the dissolved hydrogen content influenced the crack growth rate. Such results are consistent with those reported
previously. 相似文献
73.
Bum-Jin Chung Jeong-Hwan Heo Min-Hwan Kim Gyeong-Uk Kang 《International Journal of Heat and Mass Transfer》2011,54(1-3):135-141
Natural convection experiments inside a vertical cylindrical cavity were performed for Rayleigh numbers of 1.08 × 1010–2.11 × 1013 and for four different geometrical arrangements: both-open (pipe-shape), bottom-closed (cup-shape), top-closed (cap), and both-closed (cavity) cylinders. A copper electroplating system was employed for the measurements of heat transfer rates using analogy concept. The lids used to close top or bottom were adiabatic; i.e. inactive surfaces in the electrodeposition experiments. The bottom-closed cavity showed the highest heat transfer rates and then followed both-closed, both-open, top-closed ones in both laminar and turbulent flows. The results were in satisfactory agreements with the existing correlations developed for similar geometrical configurations and the empirical correlations were derived. The numerical simulations were carried out using the FLUENT 6.2 to explain the measured results. The analysis of the streamline and the local Nusselt number gave explanations for the observation. 相似文献
74.
After final annealing, the cube + Goss texture is stronger at the higher final thickness reduction. The annealing texture becomes stronger with the decreasing bulk sulfur content. At a fixed bulk sulfur content, the cube + Goss texture is well developed under a pure hydrogen atmosphere compared with a mixed-gas atmosphere. The excellent magnetic properties are obtained from the strip containing the bulk sulfur content of 6 ppm. 相似文献
75.
The carbide growth kinetics enhanced in grain interiors is mainly due to the increased diffusivity in the direction normal
to the tensile stress. The accelerated kinetics at the grain boundaries normal to the tensile stress is due to the increased
grain boundary energy and the widened grain boundary path producing the increased diffusivity in the direction normal to the
tensile stress. A strong segregation behavior of impurities to the grain boundary carbide interfaces follows the enhanced
grain boundary carbide growth kinetics. 相似文献
76.
77.
Yasantha Athukorala Ki‐Wan Lee Eun‐Ju Park Moon‐Soo Heo In‐Kyu Yeo Young‐Don Lee You‐Jin Jeon 《Journal of the science of food and agriculture》2005,85(14):2341-2348
The antioxidant activity of an extract of Grateloupia filicina was evaluated using linoleic acid and fish oil as substrates in an induct period at 65 °C. Furthermore, the algal extract was subjected to comet assay to evaluate its protecting ability for H2O2‐induced DNA damage in rat lymphocytes. Progression of oxidation was examined using weight gain, peroxide value (PV), 2‐thiobarbituric acid reactive substances and conjugated diene data. Effectiveness of the extract at 0.03 and 0.05% levels was superior to that of α‐tocopherol at 0.01% and the activity of 0.05% extract was higher than that of butylated hydroxyanisole and butylated hydroxytoluene at 0.01%. Also, the algal extract significantly inhibited H2O2 induced DNA damage in comet assay. The maximum DNA damage inhibition (68.9%) was recorded from the 50 µg ml−1 alga extract when the rat lymphocyte cells were treated with 50 µM H2O2. Copyright © 2005 Society of Chemical Industry 相似文献
78.
Keun Heo JuHwan Lim Mun J. SungWoo Hwang 《Microwave and Wireless Components Letters, IEEE》2007,17(3):160-162
We report fabrication of miniaturized low temperature co-fired ceramic helical (3-D) inductors with more than seven layers of helices and the conductor linewidth of 100mum. We achieve the QmaxLeff/A product ranging from 200 to 370. Such high values are possible thanks to the drastic reduction of the active area and still acceptably large Qmax and self-resonant frequency. High frequency characterization of the inductors is performed up to 12GHz, and a new equivalent circuit model considering vertical electromagnetic coupling between conductors is shown to reproduce all the measured characteristics 相似文献
79.
Abstract. The objective of this paper is to develop default priors when the parameter of interest is the autocorrelation coefficient in normal regression models with first-order autoregressive residuals. Jeffreys' prior as well as reference priors are found. These priors are compared in the light of how accurately the coverage probabilities of Bayesian credible intervals match the corresponding frequentist coverage probabilities. It is found that the reference priors have a definite edge over Jeffreys' prior in this respect. Also, the credible intervals based on these reference priors seem superior to similar intervals based on certain divergence measures. 相似文献
80.