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近年来, 设计合成荧光碱基类似物成为科学家研究的一个热点. 利用含时密度泛函理论考察了腺嘌呤类似物x-腺嘌呤的电子激发态性质, 计算了其电子吸收光谱和荧光光谱, 并对其若干低能电子激发态进行了详细解析归属. 同时考察了甲醇溶剂、糖环和与胸腺嘧啶配对对其光谱性质的影响. 研究表明, 在低能区域, x-腺嘌呤的吸收光谱与天然腺嘌呤相比发生了很大红移, 使其可以被选择性地激发. 计算得到的吸收光谱和荧光光谱与实验值符合很好. 溶剂化和糖环对x-腺嘌呤的电子吸收光谱具有增色效应, 同时发现溶剂化和糖环均使其荧光发生红移, 而碱基配对对其最低激发态ππ* 和荧光发射无显著影响, 但使其最低nπ* 态发生显著蓝移.
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x-腺嘌呤')" href="#">x-腺嘌呤
电子吸收光谱
荧光光谱
含时密度泛函 相似文献
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The behavior of ion-beam-induced crystallization of a buried amorphous layer created by means of MeV Si+ irradiation at 300℃ in Si(100) was studied by Rutherford backscattering and channeling technique. Sohd phase epitaxial crystallizations occurred from both the front and the back amorphous-crystalline(a/c) interfaces with the growth thickness being increased linearly with increasing dose of the annealing ion beam, Nuclear energy deposition was proved to play a dominant role in the process of ion-beam-induced crystallization. The high density of electronic excitation, which could enhance defect production near or at the a/c interface, may thus enhance the nuclearly normalized growth rate of ion-beam-induced crystallization at the front a/c interface. 相似文献
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根据群论及原子分子反应静力学的有关原理,推导出NaH和AlH分子基态(X~1Σ~+)的合理离解极限.使用密度泛函方法中的B3LYP、B3PW91和MPW1PW91方法,在6-311++G,6-311++G(3df,3pd),cc-pVQZ和aug-cc-pVQZ基组下对NaH和AlH分子的基态进行结构优化计算,使用优选的B3PW91/6-311++G(3df,3pd)对基态单点能扫描计算,然后用最小二乘法拟合Murrell-Sorbie函数,得到对应的势能函数参数及光谱常数.结果表明,采用Murrell-Sorbie函数计算所得的光谱常数与实验结果符合的很好,能精确地描述NaH和AlH分子基态的势能函数. 相似文献
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A pulsed master oscillator power amplifier system is constructed using a double-cladding polarized Ybdoped fiber and an all-fiber Q-switched narrow-linewidth pulsed laser used as seed laser.This system has a high repetition rate and provides a nanosecond pulsed laser with a narrow linewidth and linear polarization.Moreover,it generates amplified radiation with up to 14 W of average power,narrow linewidth(full-width at half-maximum is smaller than 0.12 nm),linear polarization at 1 080-nm wavelength,repetition rate of 51 kHz,and pulse duration of approximately 50 ns.Based on this pulsed amplified radiation,3.5 W of green laser,with an optical-to-optical efficiency of 27.3%,is obtained via single-pass frequency doubling using a noncritical phase matching KTP crystal. 相似文献
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用卢瑟福背散射/沟道技术和光致发光测试技术研究了室温下350keVYb~+以1×10~(15)Yb·cm~(-2)的剂量注入单晶硅后,在不同快速热退火温度下表面非晶层的固相外延结晶,结晶过程中Yb的迁移和其光致发光发射。在800,900和1000℃快速热退火温度下,表面非晶层的固相外延结晶都在掺杂区域发生中断,同时观察到Yb在晶体/非晶界面和表面的双偏析新现象,并且Yb的光致发光强度随退火温度的增加而增加。但在1200℃退火温度下,表面非晶层则完全结晶,伴随着结晶过程Yb几乎全部堆积到了表面附近,并导致了
关键词: 相似文献