The wavenumbers, heights, areas, and full widths at half-maximum (FWHM) were determined for the OH-stretching bands at ~3697 ( ν 1 ), ~3670 ( ν 2 ), ~3652 ( ν 3 ), and 3620 cm –1 ( ν 4 ) by decomposition and fitting of the FTIR spectra. The FWHM(ν 1 )/FWHM(ν 4...
摘 要: 以傅里叶红外光谱(FTIR )为分析手段,研究以苯酚为溶剂、酸催化条件下核桃壳纤维素降解过程中其主 要化学基团特征随反应时间的变化。结果表明:上述过程虽然可以用液化来描述,但本质上是核桃壳纤维素的降 解反应,纤维素分子链降解为低聚糖及葡萄糖等低分子物质,最终导致吡喃环开环。关键词: 核桃壳;纤维...
For both wetting states, evanescent waves at higher wavenumbers are found to decay faster with distance, indicating more attenuation of the OH-stretching band. In order to quantitatively characterize the water absorption, the total intensity contributing to the absorption bands is calculated as the ...
3410 cm-1: OH stretching of adsorbed water 1603 cm-1: OH bending mode of adsorbed water1047, ...
The method is based on the finding that the infrared absorptivity of fired clay minerals, measured at the Si–O–Si stretching resonance band, is negatively correlated with firing temperature. Moulds and mould cores dating to the Early Shang period (sixteenth to fourteenth century BCE) are found...
A relatively strong band centered at 3186 cm− 1 corresponding to the OH stretching represents the hydroxyl groups of the flavonoid but can also be an indication that apigenin increases the water fraction bound to the membrane. The spectral shift of the band at 1354 cm− 1, representing ...
This will eliminate the strong C═O stretching absorption band near 1673 cm− 1 from contaminant CF3COO− [5]. Lipid-peptide mixtures are prepared by dissolving them together in a 1:2 MeOH/CH2Cl2 mixture, dispersing the solution on the top of the prism and drying the solution in even...
Fig.2TheOHstretchingbandsofcholicacidatlowtempera tureNosignificantdifferencescanbeobservedbetween thespectrausingK rpelletandFluorolubemullmeth ods 既然压力效应能使不同制样方法所得的胆固醇表现出明 显的光谱差别,那么,为什么在胆酸中却看不到如此明显的光 ...
5, indicate that the broad intermolecular H-bonded OH stretching band (3450–3400 cm−1) is almost unchanged with the surface pressure. Even in the spectrum of LB film fabricated at the surface pressure of 10 mN/m, the OH stretching band appears at 3446 cm−1. Thus, it was believed...
the INTENSITY of the absorption band!!! Here we can see some of the absorbances of the methylene (CH2) fragment in the spectrum of ethyl acetate. Each vibration, called a fundamental mode, has a specific energy (or frequency) which depends on the atoms involved in the motion (i.e., ...