996 resultados para FT-Raman
Resumo:
The C-H stretching, C-H bending, C-C stretching and the low-frequency vibration regions have been investigated by Raman spectroscopy for [n-CnH2n+1NH3]2 ZnCl4 with n=7 approximately 12, 16. It is found that their frequency and relative intensities are related to the length of carbon chain in the molecules and present the odd-even effect to carbon atom numbers in chain. Some changes in spectra are interpreted in terms of the different molecular packing and interaction of chain.
Resumo:
嵌段高聚物、均聚物共混体系相容性是近年来研究的热点。本工作以光学显微镜、DSC、FT-IR为手段,研究了三嵌段高聚物苯乙烯-丁二烯-苯乙烯(SBS);SBS-48、SBS-30,SBS-28与聚乙烯基甲基醚共混体系的相容性。DSC结果表明,随SBS中PS含量的升高,体系相容性变好,PS段分子量增大,也有助于体系相容。FT-IR结果表明PVME中COCH_3在1100cm~(-1)附近呈现的双峰的相对强度对体系的相容性十分敏感,而由于苯环C—H振动产生的698cm~(-1)峰位却不象PS/PVME体系那样随相容性的改变而有显著的改变。总而言之,嵌段高聚物SBS/均聚物PVME共混体系中,体系的相容性依赖于嵌段高聚物在体系中的组份含量及嵌段高聚物中PS的重量百分含量,PS段分子量的大小对体系相容性也有影响。
Resumo:
测定了[n-C_nH_(2n+1)NH_3]ZnCl_4(n=7~12,16)配合物在碳氢伸缩、碳氢弯曲、碳碳伸缩和低频区的Raman光谱.发现它们的频率和相对强度与分子中烷基链的链长有关,并且表现出碳原子数的奇偶效应.从不同的分子堆积结构和分子间相互作用的角度讨论了光谱变化.
Resumo:
The C-H stretching, C-H bending, C-C stretching and the low-frequency vibrational regions have been investigated by Raman spectroscopy for [n-CnH2n+1NH3]2ZnCl4 with n = 7-12, 16. The frequencies and relative intensities are related to the length of the carbon chain in the molecules and present the odd-even effect of the carbon atom numbers in the chains. Some changes in the spectra are interpreted in terms of the different molecular packing.
Resumo:
The low-frequency Raman spectrum of n-decylammonium chloride was measured as a function of temperature in the temperature range from 290 to 340K, and the longitudinal acoustical mode vibration band was assigned. The results showed that there are two phase transitions at 313K and 321K, respectively. The phase transition at 313K is mainly induced by change of hydrocarbon chain conformations, while that at 321K is mainly induced by change of order degree of molecular packing. The results suggest low-frequency Raman spectroscopy is a useful probe of structural phase transition for long-chain compounds.
Resumo:
The complexes of rare earth ions with glutathione were prepared and charactrized by IR and Raman spectroscopy in the solid state. Based on the spectral results, the structure and coordination sites of the ligand in these complexes were determined.
Resumo:
谷胱甘肽是广泛存在于体内的重要三肽,在体内主要以还原型(GSH)存在,其中血液红细胞内浓度高达2mmol·L~(-1)。GSH不但是清除体内过氧化物的还原剂,而且与某些金属的配合物具有酶活性,有重要的生理生化功能,成为生物无机化学研究的重要课题。随着稀土的广泛应用,稀土的生物效应已引起广泛关注。研究稀土与GSH的配合物结构和性质,将有利于了解稀土在体内的代谢和作用。个别稀土与GSH在溶液中的配合物生成虽有报道,但系列稀土配合物的光谱和结构迄今未被研究。我们合成了十五种稀土与GSH的固体配合物,用IR和Raman光谱研究了配体在配合物中的变化及与稀土的配合位置。
Resumo:
Adsorption and oxidation of chlorobenzene on Al(2)O(3), TiO(2)-Al(2)O(3), and MnO(x)/TiO(2)-Al(2)O(3) have been studied by in situ Fourier transform infrared (FT-IR) spectroscopy. At room temperature, chlorobenzene is only physisorbed on Al(2)O(3), TiO(2)-Al(2)O(3), and MnO(x)/TiO(2)-Al(2)O(3), and gives the same IR spectrum as that for liquid-phase chlorobenzene. On Al(2)O(3) no further interaction and reaction take place with treatment, at higher temperatures (up to 773 K), while phenolates are observed for TiO(2)-Al(2)O(3) and MnO(x)/TiO(2)-Al(2)O(3) at 773 K. When the adsorbed chlorobenzene coexists with oxygen, formates are detected for Al(2)O(3), while acetates are additionally observed for TiO(2-)Al(2)O(3) above 573 K. For MnO(x)/TiO(2-)Al(2)O(3), maleates are present at 573 And 673 K, while formates and acetates develop at 473 and 573 K. Almost all IR bands due to formates, acetates, and maleates disappear at 773 K, indicating that these oxygen-containing species are potential intermediates for the total oxidation of chlorobenzene.