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991.
Toshimasa Hashimoto Kiyoshi Ogita Susumu Umemoto Tetsuya Sakai 《Journal of Polymer Science.Polymer Physics》1983,21(8):1347-1356
Thermoluminescence (TL) has been observed in γ-irradiated extended-chain crystals of polyethylene above room temperature. The TL curve, which exhibits four peaks at 50, 90, 120, and 140°C, is different from that given by folded-chain crystals, in both shape and intensity. In particular, a shape, strong glow peak is observed at 140°C, corresponding to the melting temperature of the extended chain crystals. These results are discussed in relation to independent measurements by differential scanning calorimetry and electron spin resonance. 相似文献
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996.
Amorphous carbon nitride film preparation by plasma-assisted pulsed laser deposition method 总被引:1,自引:0,他引:1
M. Itoh Y. Suda M.A. Bratescu Y. Sakai K. Suzuki 《Applied Physics A: Materials Science & Processing》2004,79(4-6):1575-1578
Amorphous carbon nitride (aCNx) films were prepared by pulsed laser ablation of graphite in N2 RF plasma. The film property was compared with that prepared in N2 gas. The N2 plasma was generated by a mesh electrode, which was inserted between a graphite target and a Si substrate. The gas pressure pN2 was varied from 10 to 100 mTorr. The film deposition rate exponentially decreased with pN2 for both the plasma and gas environment. X-ray photoelectron spectroscopy analysis showed that the ratio of nitrogen content to the carbon one ([N]/[C]) of the aCNx film surface deposited in the N2 plasma was 2 times higher than that obtained in the N2 gas. The film structure was shown by Raman spectroscopy analysis that sp2 clustering was enhanced with increasing the [N]/[C]. The effect of plasma on aCNx film deposition was discussed. PACS 81.15.Fg; 79.60.-i; 81.05.Uw 相似文献
997.
Sakai H Sekiguchi K Witala H Glockle W Hatano M Kamada H Kato H Maeda Y Nogga A Ohnishi T Okamura H Sakamoto N Sakoda S Satou Y Suda K Tamii A Uesaka T Wakasa T Yako K 《Physical review letters》2000,84(23):5288-5291
The cross section, the deuteron vector A(d)(y) and tensor analyzing powers A(ij), the polarization transfer coefficients K(y('))(ij), and the induced polarization P(y(')) were measured for the dp elastic scattering at 270 MeV. The cross section and A(d)(y) are well reproduced by Faddeev calculations with modern data-equivalent nucleon-nucleon forces plus the Tucson-Melbourne three-nucleon force. In contrast, A(ij), K(y('))(ij), or P(y(')) are not described by such calculations. These facts indicate the deficiencies in the spin dependence of the Tucson-Melbourne force and call for extended three-nucleon force models. 相似文献
998.
Y. Okano T. Suzumura S. Sakai Y. Hayakawa M. Kumagawa A. Hirata S. Dost 《Mechanics Research Communications》2004,31(5):605-610
The effect of coexistence of Marangoni and natural convections was studied numerically in melting of a GaSb/InSb/GaSb sandwich sample. Fluid flow and concentration fields are oscillatory when the solutal natural convection coexists with the thermal Marangoni convection. The coexistence of solutal and thermal natural convections, without Marangoni convection, however, does not lead to fluid flow oscillations in spite of the existence of two flow cells in opposite directions. The conclusion is that not the presence of two opposite flow cells but the flow structure itself, due to the presence of a free surface, is responsible for such an oscillatory behaviour. 相似文献
999.
Katsuhiro Sakai 《国际流体数值方法杂志》1995,21(11):1041-1048
In order to obtain stable and accurate numerical solutions for the convection-dominated steady transport equations, we propose a criterion for constructing numerical schemes for the convection term that the roots of the characteristic equation of the resulting difference equation have poles. By imposing this criterion on the difference coefficients of the convection term, we construct two numerical schemes for the convection-dominated equations. One is based on polynomial differencing and the other on locally exact differencing. The former scheme coincides with the QUICK scheme when the mesh Reynolds number (Rm) is $\mathop \[{\textstyle{{\rm 8} \over {\rm 3}}}\] $, which is the critical value for its stability, while it approaches the second-order upwind scheme as Rm goes to infinity. Hence the former scheme interpolates a stable scheme between the QUICK scheme at Rm = $\mathop \[{\textstyle{{\rm 8} \over {\rm 3}}}\] $ and the second-order upwind scheme at Rm = ∞. Numerical solutions with the present new schemes for the one-dimensional, linear, steady convection-diffusion equations showed good results. 相似文献
1000.
Oxidative Coupling of Terminal Alkynes with Aldehydes Leading to Alkynyl Ketones by Using Indium(III) Bromide
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Dr. Yohei Ogiwara Masahito Kubota Kotaro Kurogi Dr. Takeo Konakahara Prof. Dr. Norio Sakai 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(51):18598-18600
An indium(III)‐promoted direct acylation of terminal alkynes using aldehydes leading to ynones was developed. In contrast to the previous addition reactions of alkynes to aldehydes, which provide propargylic alcohols, the oxidative coupling proceeded exclusively to afford alkynyl ketones. The products were likely generated through an Oppenauer oxidation of the indium propargylic alkoxide species by excess amounts of aldehydes. 相似文献