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GCR算法的残量与系数阵谱分布界间的关系
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作者 陈金如 《南京师大学报(自然科学版)》 CAS CSCD 1990年第2期12-21,共10页
本文探讨了GCR算法的残量与系数阵谱分布界间的关系,分析了其局限性及可行性,给出了粗略的判别标准,并与古典的共轭斜量法解法方程组的方法作了比较。最后的数值试验验证了所得结论。
关键词 正实阵 GCR算法 残量 谱分布界
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Energy Dependence of Interface Trap Density——Investigated by Relaxation Spectral Technique
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作者 霍宗亮 毛凌锋 +1 位作者 谭长华 许铭真 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2003年第1期18-23,共6页
According to the definition of interface traps,a new application of relaxation spectral technique to sub-threshold swing shift and sub-threshold gate voltage shift is proposed to extract interface trap density in 1.9n... According to the definition of interface traps,a new application of relaxation spectral technique to sub-threshold swing shift and sub-threshold gate voltage shift is proposed to extract interface trap density in 1.9nm MOSFET.And thus the energy distribution of interface trap can be determined.According to the two methods,the energy profile of interface traps agrees with those reported in literature.Compared to other methods,this method is simpler and more convenient. 展开更多
关键词 relaxation spectral technique interface trap MOS structure
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Chiral Separation of Ibuprofen by Supercritical Fluid Chromatography 被引量:2
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作者 HAN Soonkoo ROW Kyungho 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第6期741-746,共6页
The separation method using chiral stationary phase (CSP) for the preparation of enantioselective compound was widely used. In this work, supercritical fluid chromatography(SFC) was proposed to resolve the chiral ... The separation method using chiral stationary phase (CSP) for the preparation of enantioselective compound was widely used. In this work, supercritical fluid chromatography(SFC) was proposed to resolve the chiral mixtures. To determine the optimum operating conditions for the chiral separation of the racemic ibuprofen, the retention factors and resolutions with the change in pressure, temperature and the content of IPA (%, by volume) in supercritical CO2 were investigated. Experiments showed that the retention factor decreased with the increase of pressure and decrease in temperature. The retention factor was also influenced by the content of IPA in mobile phase, as the content of IPA in the supercritical fluid increased, the retention factor decreased. The resolution of the enantiomers became worse with the increase of IPA in the supercritical fluid. Through optimizing the experimental conditions, a SFC procedure with 13MPa, 311.15K and 4% IPA in CO2 was obtained. The peak shape of the enantiomers was symmetric with supercritical fluid chromatography when compared to the asymmetric peak shape obtained by the conventional liquid chromatography. This work demonstrated that the developed supercritical fluid chromatography procedure was suitable for the chiral separation of ibuprofen enantiomers. 展开更多
关键词 chiral separation IBUPROFEN retention factor RESOLUTION supercritical fluid chromatography
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Almost Regularity Conditions of Spectral Problems for a Second Order Equation
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作者 Yu.A.Mamedov H.I.Ahmadov 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第5期649-654,共6页
The asymptotic distributions are exactly solved for linearly independent solutions considering problem of the second order and for the coefficients of asymptotic distribution the recurrent formulas are obtained. Furth... The asymptotic distributions are exactly solved for linearly independent solutions considering problem of the second order and for the coefficients of asymptotic distribution the recurrent formulas are obtained. Further, using obtained recurrent formulas the necessary and sufficient conditions for almost regularity of spectral problem for the equation of the second order is proved. 展开更多
关键词 spectral problem asymptotic distribution
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