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Two new CdⅡ-based coordination polymers(CPs) with mixed adenine(Hade) nucleobase and 5-nitroisophathalate(nip) ligands, {[Cd(Hade)_(0.5)(H_2O)_2(nip)]·H_2O}n 1 and {[Cd(Hade)(H_2O)_(1.25)(CH_3OH)0.75(nip)]·0.75 CH_3OH·0.5H_2 O}_n 2, were successfully obtained by varying the preparation methods and structurally characterized. Crystal data for 1: monoclinic, C2/c space group with a = 10.5546(6), b = 17.3496(6), c = 16.1198(9) ?, β = 104.2800(10)o, V = 2860.6(2) ?3, Dc = 2.058 g/cm~3, Mr = 443.13, Z = 8, F(000) = 1752, μ = 1.585 mm~(–1), the final R = 0.0394 and wR = 0.1109 for 2285 observed reflections with I 2σ(I). For 2: triclinic, P1 space group with a = 10.2032(7), b = 10.5098(8), c = 11.0223(8) ?, a = 65.7050(10)o, β = 74.5750(10)o, g = 61.5280(10)o, V = 943.38(12) ?~3, Dc = 1.888 g/cm3, Mr = 536.24, Z = 2, F(000) = 537, μ = 1.225 mm~(–1), the final R = 0.0225 and wR = 0.0702 for 3143 observed reflections with I 2σ(I). 1 presents a crisscrossed layer with mutually orthogonal {Cd(nip)} chains aggregated by neutral m-N(7),N(9)-Hade connector. By contrast, 2 displays a linear chain with CdⅡ ions extended by bis-bidentate chelating-nip2–connectors, which are further assembled into a broad ribbon by N-H···N hydrogen-bonding interactions. Additionally, the two solid-state samples with comparable thermal stability exhibit favorable luminescent emissions at room temperature, suggesting their potential applications as fluorescence materials. 相似文献
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大尺度正压大气环流的波动特征对理解气候变化具有重要的意义,而非线性浅水波方程组是描述大尺度正压大气环流的原始控制方程.本文对线性方程的复变函数解,通过二次适当的移植,求得浅水波方程组的发展方程的扰动位势的实变函数解,该实变函数解析解由基流项和波动项两部分组成.其中基流由波数、波速、β效应、变形半径和时间的任意函数共同决定;波动项与β效应有关.分析表明,在大尺度正压大气环流中扰动位势存在曲面的周期波和孤波的现象,周期波与孤波相互调制而呈现不稳定性;当多个周期孤波同时出现时,则彼此独立传播;扰动位势波动项中的时间任意函数对曲面周期孤波的波幅有调制作用,可控制波的产生、发展和消失.所得结果对研究大气波动现象和气候变化具有一定的理论参考价值. 相似文献
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在高功率光纤激光系统中,包层光滤除器能将光纤中包层光滤除以保证输出激光光束质量,光纤端帽通过对输出激光扩束降低输出光纤端面的光功率密度,从而保护光纤端面不受损坏,两者都是高功率光纤激光系统稳定运行的重要核心器件。将包层光滤除器和光纤端帽进行一体化设计,制备了一体化高功率光纤包层光滤除器和光纤端帽并分别应用于20 kW合束系统和单纤系统中,输出功率达到20 kW时,端帽的最高温度约为40℃,温升速率约为0.8℃/kW。 相似文献
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给定一个离散且有限随机变量的信息熵,求其对应的概率分布需要解多元非线性方程,文中提出了一个将n元信息熵方程化为至多(n-1)个一元非线性方程求解的算法,证明了算法的正确性,给出了算法误差估计;运用熵方程求解算法设计了一种基于信息熵的文本数字水印方案. 相似文献