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YUN-LIANG LI CHEONG WAN LEE KING HUNG LEUNG GUO ZHONG HE DAVID LEE PHILLIPS 《Molecular physics》2013,111(16):2659-2663
We report ultraviolet resonance Raman spectra of bromoform (CHBr3) in cyclohexane solution. The resonance Raman spectra show significant intensity in the overtones of the nominal Br-C-Br symmetric bend (v 6), the nominal H-C-Br asymmetric bend (v3), the nominal Br-C-Br symmetric stretch (v 2) and the nominal Br-C-Br asymmetric stretch (v 5) vibrational modes suggesting that the short-time photodissociation dynamics have noticeable multidimensional character. The lack of strong combination bands between several of the Franck-Condon active modes suggests that more than one electronic transition contribute to the resonance Raman spectra. We briefly discuss the ultraviolet short-time photodissociation dynamics of bromoform and the potential implications for the secondary photodissociation reactions of the initially formed CHBr2 radical. 相似文献
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The (ν,0) bands, for ν = 0–5, of the B1Π-X1Σ transition of YBr between 806.2–891.2 nm have been studied using the technique of laser vaporization/reaction with supersonic cooling and laser-induced fluorescence spectroscopy. Spectra of both the Y79Br and Y81 Br isotopic molecules were observed and analysed. A least-squares fit of all the measured line positions yielded vibrational and rotational constants for the B1Π state. The equilibrium bond length of the B1Π state is determined to be 2.622 5(2) Å. 相似文献
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HOPF BIFURCATION ANALYSIS OF A ROTOR/SEAL SYSTEM 总被引:2,自引:0,他引:2
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两种新型双极有机小分子发光材料的合成与发光 总被引:3,自引:0,他引:3
设计和合成了两种新的具有“双极(bipolar)”性质和发光性能的有机小分子化合物N-[4-(5-(2-苯基喹啉-4)-1,3,4-噁二唑-2)苯基]-N'-苯基-N,N'-二苯基-1,1'-联苯基-4,4'-二胺(TPDOPQ)和N,N'-双{4-[5-(2-苯基喹啉-4-基)-1,3,4-噁二唑-2]苯基}-N,N'-二苯基-1,1'-联苯基-4,4'-二胺[TPD(OPQ)2]. 用1H NMR, MS和元素分析进行了表征, 研究了化合物的热稳定性和光致发光性质, 并用循环伏安法测定了其电化学性能. 结果表明, 这两种合成的有机化合物同时具备空穴传导和电子输入双重功能, 光致发光性能优良, 热稳定性好, 能形成均衡薄膜, 因此可作为制作有机电致发光器件的候选材料. 相似文献
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含芳胺和1,3,4-噁二唑的星型有机分子合成及光电性质 总被引:2,自引:0,他引:2
通过分子设计, 采用多步反应合成了2种新型的具有“双极”(Bipolar)性质和发光性能的以N原子为中心的星型有机分子. 用1H NMR, MS和元素分析进行了表征, 研究了化合物的热稳定性和固体粉末的光致发光性质, 并用循环伏安法测定了其电化学性能. 结果表明, 这种同时具备空穴传导和电子输入双重功能基团的星型有机小分子的光致发光性能优良(量子效率达到82%—95%), 热稳定性好, 可以作为有机电致发光器件材料. 相似文献
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WANG Xiao-Ru HU Guang-Lin CHEN Bin CHEN Den-Yun ZHUANG Zhi-Xia Frank S. C. LEE LEUNG Hei-Wun YEUNG Hin-Wing C. W. MCLEED 《高等学校化学学报》2000,21(Z1):25
One of the major problems in marketing Chinese Medicinal (CM) material product is the issue of product safety. Alarm has been heightened internationally in recent years to control the contents of metals such as Cd, Pb, Hg and As and toxic contaminants such as residue pesticides in CM product. Cases of severe and fatal poisoning have occurred after the consultation of contaminated CM products, or adulterated ones containing toxic substitutions. Such incidences have severely damaged the overall image of CM products. It therefore comes as no surprise that in the recommendations put forward recently in China, the control of metals and toxic contaminants in CM products is a top priority item requiring proper action. 相似文献
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炮附片、黑顺片和白附片二维红外相关光谱的分析研究 总被引:8,自引:2,他引:6
采用红外光谱法(FTIR)并结合二维相关(Two-dimensional Correlation Spectroscopy)分析技术,对炮附片、黑顺片和白附片进行了无损快速鉴别研究。炮附片、黑顺片和白附片在一维谱图上差别不明显,而在二维谱图上凭借各官能团相互作用强度的不同而可以进行一一鉴别。在900~1500cm~(-1)波段内,炮附片在同步图上有一个较强的自动峰,在1220cm~(-1)附近。而黑顺片和白附片不仅在1220cm~(-1)有一个较强的自动峰,还在1200和1400cm~(-1)附近出现了自动峰,且白附片在1400cm~(-1)附近的自动峰比黑顺片的要更强一些;在交叉线的两侧,三者各官能团正的交叉峰白附片最多,黑顺片次之,炮附片最少。结果表明:凭借炮附片、黑顺片和白附片的二维红外相关谱可以作为药材不同炮制法的鉴别依据。该法快速、准确,为中药材的炮制鉴别提供了一种新的方法和手段。 相似文献
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