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In this paper, we have systematically analyzed the degenerate and nondegenerate two-photon polarization ratios of various point groups. We present the maximum of symmetry assignments of two-photon transition with the combination of degenerate and nondegenerate two-photon absorption. These results provide the theoretical basis for the experimental assignments. 相似文献
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光学多道分析仪是七十年代发展起来的一种光谱同时探测仪器.光谱信息的获取通常有两种方式:一是对感兴趣的波段进行依次扫描,二是对该波段进行同时探测.前者是以出缝-光电倍增管组合的方法为代表,后者则是以光谱干板的应用最为广泛.但是,这种同时探测器的灵敏度低,转换特性一般不呈线性(即乳剂特性γ≠1),其准确度和精密度也很差,波长定标比较麻烦.而且,所收集到的光谱信息只有在感光板显影后才能证实其有效性?... 相似文献
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三(2-苯并咪唑甲基)胺-锌(Ⅱ)配合物模拟水解酶催化酯类水解研究 总被引:3,自引:0,他引:3
研究了三(2-苯并咪唑甲基)胺-锌(II)配合物作为水解酶模拟物催化乙酸对硝基苯酯(NA)水解动力学.结果表明,催化水解速率对NA及配合物浓度呈一级反应.水解速率遵循速率方程v=(kcat[Zn]+kOH[OH-]+k0)[NA].在298K,I=0.10mol/LKNO3,0.02mol/LTris,40%CH3CN水溶液中,二级反应速率常数kcat和kOH分别为0.12、1.45mol-1·L·S-1,k0为NA溶剂解的速率常数,其值为3.70×10-6s-1.与10%CH3CN溶液中的k0值相比,40%CH3CN水溶液中的k0值明显降低.本研究表明三(2-苯并咪唑甲基)胺-锌(II)配合物能有效地催化NA的水解.配合物对NA水解的催化作用受酸碱平衡控制.根据实验结果提出了催化反应的机理. 相似文献
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There are two dynamical stable zones in the operation of solid laser containing a thermal lens. In this paper, we point out that in the two stable zones two kinds of dynamical stable states can exist in a laser resonator: mode-steady thermo-stable state and power-steady thermo-stable state. They are different from each other in general. The operating conditions for power-steady thermo-stable state are presented. A cw Nd: YAG thermo-stable resonator operating in power-steady states has been designed, and 40 W TEM00 output power in 1.06μm is obtained experimentally. 相似文献
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A polarization-selected three-photon resonant multiphoton ionization investigation of the 3p Rydberg region of the spectra of m-dimethylbenzene has been conducted. Several vibronic states have been discovered and also assigned for the first time. 相似文献
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含新型亲核体大环多胺锌(II)配合物对水解酶的模拟研究 总被引:5,自引:0,他引:5
本文探讨苯酚功能化的大环多胺配体6-(2'-羟基-3', 5'-二溴)-苄基-1, 4, 8, 11-四氮杂环十四烷(L)锌(II)配合物作为水解酶模拟物催化4-硝基苯酚醋酸酯(NA)水解的动力学。研究表明催化水解速率对NA及配合物浓度皆呈一级反应。水解速率遵循速率方程V=(kcat[Zn]+kOH[OH^-]+k0)[NA]。其二级反应速率常数kcat在一定范围内随着pH值的增加而增加, kcat的最大值(k)和kOH分别为0.12, 8.55mol^-^1.L.s^-^1。k0为NA的溶剂解速率常数, 其值为1.122×10^-^5s^-^1(298K, I=0.10,0.02mol.L^-^1tris缓冲溶液)。kcat值较以前报道的配合物更大, 催化活性更高。显示配位酚羟基可作为一种新型亲核体有效地催化NA的水解。配合物对NA水解的催化作用受酸碱平衡控制。根据实验结果提出了催化反应的机理。 相似文献