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991.
Kerim Isik Yoshinori Yoshida Lin Chen Till Clausmeyer A. Erman Tekkaya 《Comptes Rendus Mecanique》2018,346(8):770-778
This paper presents a methodology to model a blanking process using a continuum mechanical damage model. A variant of the Lemaitre model, in which the quasi-unilateral conditions are taken into consideration to modify the damage behavior under compressive stress states, is selected as material model. S45C high-carbon steel is analyzed experimentally. To characterize the damage behavior of the material, notched round bar tensile tests with three different notch radii (6 mm, 10 mm, and 20 mm) using image analysis are performed. Using digital image processing, the strain at the deformation zone can be computed for the load–strain curves. Those curves are used as an objective function to determine the parameters of the Lemaitre damage model. The experimental results are compared with the results of the FE analysis of the tensile test. The identified model parameters are used in numerical investigations of axisymmetric blanking. The effect of the model's extension to quasi-unilateral damage evolution is discussed. The crack progress in high-carbon steel sheet during blanking and the final sheared part morphology are predicted and compared with the experimental results. Sheared surface and burr height obtained by the analysis coincide with the results of the blanking experiment. 相似文献
992.
993.
Mayumi B. Takeyama Atsushi Noya Shozo Kambara Yuichiro Hayasaka Hideaki Machida Kazuya Masu 《Applied Surface Science》2009,256(4):1222-1226
We have prepared thin Zr-B films at low temperatures as a new material applicable to an extremely thin barrier against Cu diffusion in Si-ULSI metallization. The obtained Zr-B films mainly consist of the ZrB2 phase with a nanocrystalline texture on SiO2 and a fiber texture on Cu. The resistivity of the Zr-B films depends on the substrate of SiO2 or Cu. The constituent ratio of B/Zr is almost 2, though the contaminants of oxygen, nitrogen, and carbon are incorporated in the film. The nanocrystalline structure of the Zr-B film on SiO2 is stable due to annealing at temperatures up to 500 °C for 30 min. We applied the 3-nm thick Zr-B film to a diffusion barrier between Cu and SiO2, and the stable barrier properties were confirmed. We can demonstrate that the thin Zr-B film is a promising candidate for thin film application to a metallization material in Si-ULSIs. 相似文献
994.
R. Yoshida H. Okazaki K. Iwai K. Noami T. Muro M. Okawa K. Ishizaka S. Shin Z. Li J.L. Luo G.-Q. Zheng T. Oguchi M. Hirai Y. Muraoka T. Yokoya 《Physica C: Superconductivity and its Applications》2009,469(15-20):1034-1036
We present the data from ultrahigh-resolution laser-excited photoemission spectroscopy on a newly discovered noncentrosymmetric superconductor Mg10Ir19B16. We observed the evidences for the opening of superconducting gap where numerical fittings show that isotropic s-wave model can satisfactorily explain the behavior of spectra near the Fermi level. We also present the valence band photoemission spectrum and B K fluorescence spectrum to discuss the basic electronic structure of Mg10Ir19B16. 相似文献
995.
996.
997.
998.
Keiichiro Yoshida Toshiaki Yamamoto Tomoyuki Kuroki Masaaki Okubo 《Plasma Chemistry and Plasma Processing》2009,29(5):373-386
A pilot-scale pulse corona induced plasma chemical process (PPCP) reactor for controlling gas-phase dioxins and NO
x
simultaneously is installed in a garbage incineration plant. The flow rate of the sampled flue gas is 5,000 Nm3/h (N: standard state) in maximum at the PPCP reactor, which consists of 22 wire-cylinder electrodes and is energized by a
50 kW nanosecond pulse high voltage generator. With an applied plasma energy density of 2.9–6.1 Wh/Nm3, the decomposition efficiency for dioxins is 75–84% based on TEQ (toxic equivalents); the conversion efficiency of NO to
NO2 is ~93% at maximum. The flue gas treated by the PPCP reactor is introduced at a rate of 50 Nm3/h to a wet-type chemical reactor, which uses an aqueous solution of sodium sulfite (Na2SO3). More than 90% of NO
x
is reduced to nitrogen, with negligible byproducts such as NO2
− or NO3
− ions left in the solution. 相似文献
999.
Atsuya Muranaka Dr. Osamu Matsushita Kengo Yoshida Shigeki Mori Dr. Masaaki Suzuki Dr. Taniyuki Furuyama Masanobu Uchiyama Prof. Dr. Atsuhiro Osuka Prof. Dr. Nagao Kobayashi Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(15):3744-3751
Expanded porphyrins : The electronic excited states of two forms of meso‐hexakis(pentafluorophenyl)‐substituted gold(III) hexaphyrin(1.1.1.1.1.1), such as that depicted, have been investigated by density functional calculations and magnetic circular dichroism spectroscopy to assign their low‐energy excited singlet states.
1000.
Jun Oshitani Shiho Takashina Mikio Yoshida Kuniaki Gotoh 《Colloids and surfaces. A, Physicochemical and engineering aspects》2009,350(1-3):136-140
The objective of this study is to estimate the contribution of Na+ as a counterion in the formation of H-AOT&Na-AOT-based W/O microemulsions using aqueous NaOH solution by pyranine absorbance measurements. A mixture of an aqueous NaOH solution containing pyranine/H-AOT&Na-AOT/isooctane was emulsified by changing the mixing ratio of Na-AOT (XNa-AOT = 0–1) and the mole fraction of NaOH (XNaOH = [NaOH]/the AOT− concentration in the water pool = 0–1). The phase behavior of the emulsified mixture was evaluated from the absorbance of pyranine at the isosbestic point and by visual observations. W/O microelumsions are formed at the mid-range of XNa-AOT, whereas the emulsified mixture separates into two phases at lower XNa-AOT and higher XNa-AOT. The two phase boundaries shift toward lower XNa-AOT as with increasing XNaOH. The phase behavior depends on the degree of screening of electrostatic repulsions between the polar headgroups of AOT− by the Na+ counterion. Interestingly, nano-sized W/O microemulsions are formed without phase separation using a highly concentrated NaOH aqueous solution when the Na-AOT mixing ratio is appropriately adjusted. The phase behavior was plotted as XNaOH versus XNa-AOT, and the correlation equations for the two phase boundaries were obtained by fitting the points. The contribution of the Na+ counterion from NaOH to W/O microemulsion formation was estimated by the correlation equations. The absorbance of pyranine and the size of W/O microemulsions, as measured by DLS, were plotted as a function of XNa+=(x[Na+ from NaOH]+[Na+ from Na-AOT])/[AOT−], in which x is the ratio contributed by NaOH. The absorbance and size correlates well with XNa+, indicating that XNa+ is a meaningful parameter for quantitatively estimating phase behavior and size variation. 相似文献