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101.
证明了一个因式相通定理,它是奇点理论中等价性定理的一个推广.这个定理表明单纯高阶项的开折对普适开折因式相通中的参数映射没有贡献.据此本文提出了一种因式相通中参数映射的简洁有效的近似计算方法 相似文献
102.
In this paper the miscibility of poly (ε-caprolactone) (PCL) and aliphatic polycarbonate (APC) is studied by using DSC. The results show that PCL and APC are miscible in all ranges of composition. The interaction parameter between the polymers is calculated from the melting point depression data. Using optical microscope, the shapes of the PCL spherulites in the blends are observed. 相似文献
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COMPATIBILITY IN POLYMER BLENDS OF POLY (VINYL ACETATE) AND POLY (METHYL METHACRYLATE)STUDIED BY NMR
Compatibility of poly (vinyl acetate) (PVAc) with poly (methyl methacrylate) (PMMA) mixtures has been studied by using nuclear magnetic relaxation, differential scanning calorimeter and small-angle X-ray scattering techniques. The nuclear magnetic relaxation time T_1's were measured as a function of composition in blends of PMMA and PVAc prepared from chloroform solution. The results show that the system is miscible for casting from chloroform solution. 相似文献
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The photoassociation reactions H+D^+ and H+ +D induced by the one- and two-colour laser pulses are theoretically studied. The reactions occur through two channels: (i) H(1S)+D^+ →HD^+, and (ii) H^+ +D(1S)→HD^+. The reaction probability through channel (ii) is higher than through channel (i). The populations of the products H^+ +D and HD+ and the ratio of H^+ +D to HD+ can be controlled by laser pulses. The two-colour laser pulses can more efficiently lower the dissociation probability and therefore enhance the yield ratio of the product HD+. 相似文献
108.
A Comparison between AlN Films Grown by MOCVD Using Dimethylethylamine Alane and Trimethylaluminium as the Aluminium Precursors 下载免费PDF全文
HU Wei-Guo LIU Xiang-Lin ZHANG Pan-Feng ZHAO Feng-Ai JIAO Chun-Mei WEI Hong-Yuan ZHANG Ri-Qing WU Jie-Jun CONG Guang-Wei PAN Yi 《中国物理快报》2007,24(2):516-517
Aluminium nitride (AlN) films grown with dimethylethylamine alane (DMEAA) are compared with the ones grown with trimethylaluminium (TMA). In the high-resolution x-ray diffraction Ω scans, the full width at half maximum (FWHM) of (0002) AlN films grown with DMEAA is about 0.70 deg, while the FWHM of (0002) AlN films grown with TMA is only 0.11 deg. The surface morphologies of the films are different, and the rms roughnesses of the surface are approximately identical. The rms roughness of AlN films grown with DMEAA is 47.4nm, and grown with TMA is 69.4nm. Although using DMEAA as the aluminium precursor cannot improve the AlN crystal quality, AlN growth can be reached at low temperature of 673K. Thus, DMEAA is an alternative aluminium precursor to deposit AlN film at low growth temperatures. 相似文献
109.
Autler-Townes Splitting in Photoelectron Spectrum of Three-Level Li2 Molecule in Ultrashort Pulse Laser Fields 下载免费PDF全文
The Autler-Townes (AT) splitting in femtosecond photoelectron spectrum of three-level Li2 molecules is theoretically investigated using time-dependent quantum wave packet method. With proper femtosecond laser pulses, three peaks of the AT splitting can be observed in the photoelectron spectrum. The AT splitting stems from rapid Rabi oscillation caused by intense ultrashort laser pluses. The effects of laser parameters on the molecular ionization dynamics are also discussed. 相似文献
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