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191.
采用分子动力学(MD)模拟方法在COMPASS力场下,研究了不同质量比(10/90,30/70,50/50,70/30和90/10)聚乳酸(PLA)/聚酰胺11(PA11)共混物的相容性.研究结果表明:不同比例下PLA/PA11共混物的Gibbs自由能变化均大于零,其共混物很难形成均相体系;共混体系结合能的计算以及不同组分分子间C—C原子对径向分布函数的分析揭示了PLA和PA11的相互作用主要源自其分子间的范德华力;此外,模拟得到的所有比例下共混物的Flory-Huggins相互作用参数(χ)均大于临界Flory-Huggins相互作用参数(χcritical),进一步证明PLA与PA11不能形成相容体系。 相似文献
192.
用自行组装的直流辉光放电原子发射光谱(dc G D A E S)仪器对分析铜合金的某些基本特性进行了研究 探讨了光源放电室结构、放电气体压力、放电电压等操作参数以及试样尺寸大小对放电性能及元素谱线强度的影响,并进行了优化 考察了在不同放电气压条件下样品的溅射率和优化条件下辉光放电的稳定性最后,分析了铜合金标准样品中的 Al和 Mn,结果较满意 相似文献
193.
以3-氨基-5-硝基2,1-苯并异噻唑(BIT) 为重氮组分,在适当的条件下,与单苯胺类及萘胺磺酸类衍生物偶联, 得到了从红到兰色的一系列分散染料. 这些染料均未见报导,并对其中部分染料进行了检测,证明各项性能优良,应用前景看好. 相似文献
194.
195.
INFLUENCE OF C+-IMPLANTATION DOSE ON BLUE EMISSION AND MICROSTRUCTURES OF Si-BASED POROUS β-SIC
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Crystal Si were implanted with different doses of C+ from 1011 to 1017 cm-2 at an energy of 50 keV. β-SiC precipitates were formed by thermal annealing at 1050 ℃ for 1 h and porous structures were prepared by electrochemical anodization. Under the excitation of ultraviolet, the samples, with C+ dose ≥1015 cm-2 have intense blue emission which is stronger than the photoluminescence (PL) intensity of reference porous silicon (PS), and increases as C+ dose increases; the samples with C+ dose ≤1014 cm-2 show similar PL spectra to those of PS. The blue peak intensity in PL spectra is correlated with the TO phonon absorption strength of β-SiC in infrared absorption spectra. The transmission electron microscopy study shows that the blue peak is also correlated with the microstructures. Because porous β-SiC is nanometer in size, it is suggested that the quantum confinement effect be responsible for the blue light emission. 相似文献
196.
We study the information transfer and entanglement transfer in a system consisting of single trapped ions in cavities by the three-mode cross-Kerr-like interaction among the cavity field (photons), the centre-of-mass motion (phonons) and the internal state of the trapped ion in the Lamb-Dicke and large detuning regime. 相似文献
197.
We investigate theoretically the electron transport of a two-level quantum dot irradiated under a weak laser field at low temperatures in the rotating wave approximation. Using the method of the Keldysh equation of motion for nonequilibrium Green function, we examine the conductance for the system with photon polarization perpendicular to the tunnelling current direction. It is demonstrated that by analytic analysing and numerical examples, a feature of conductance peak splitting appears, and the dependence of conductance on the incident laser frequency and self-energy are discussed. 相似文献
198.
Vapour-to-Liquid Nucleation in Associating Lennard-Jones Fluids with Multiple Association Sites
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The excess Helmholtz free energy functional for associating Lennard-Jones (L J) fluid is formulated in terms of a weighted density approximation for short-ranged interactions and a Weeks-Chandler-Andersen approximation for long-range attraction. Within the framework of density functional theory, phase equilibria, vapour-liquid surface tension and vapour-liquid nucleation properties including the density profile, work of formation, excess number of particles and critical supersaturation are investigated for associating LJ fluids with different numbers of association sites (M =1,2, 3, 4) per particle. The influences of association energy and association sites on phase equilibria, surface tension and vapour-liquid nucleation properties are discussed. 相似文献
199.
本文简要介绍了计算C G系数的生群元矩阵方程法,给出计算二十面体群C G系数时采用的简化计算方法,并给出了Ⅰ群C G系数的计算结果。 相似文献
200.
ZHOU Xin FANG JianShu LIAO XiangPing ZHU QianQuan LIU ZhiMin TANG Bin 《中国科学:物理学 力学 天文学(英文版)》2013,(9):1664-1669
The effects of different defects on optical properties and plasmon resonances properties of Au nanoshell arrays were investigated by using the finite-difference time-domain(FDTD) theory.It is found that the optical properties of the nanoshell arrays are strongly influenced by different defects.We show that when the hollow Au nanoshell arrays are placed in air,there is a wide photonic band gap(PBG) in the infrared region,but the band gap becomes narrower as we introduced different defects.Based on the distributions of electric field component E z and the total energy distribution of the electric and the magnetic field,we show that there exhibit dipoles field distributions for the plasmon mode at the long-wavelength edge of the band gap,but composite higher order modes are excited at the short-wavelength edge of the band gap.The plasmon resonant modes also can be controlled by introducing defects. 相似文献