RESUMO
Under acidic conditions, aniline can react with nitrite diazotization, then diazotization can reaction products under the condition of alkaline naphthol coupled with armor and color. The product of this reaction has a maximum absorption at 495 nm. By using a series of optimized experiments, we obtained the optimum instrument operation parameters and reaction conditions to analyze aniline in leather extract solutions. Under optimal conditions, aniline concentration was within the range of 0.002-2.0 mg/L, and peak height (H, mV) and concentration (c, mg/L) had a linear relationship. The linear correlation coefficient was R2 = 0.9997, the detection limit was 1.62 µg/L, and the RSD was 0.71%. Aniline in leather extract after accelerated aging was calculated using our calculation method, and the range of standard addition recovery was recorded to be between 97.8% and 103.8%. Compared with the national standard anti-interference method, our result recorded more accurate results and the relative mean absolute error (RAAE) was smaller. Our flow injection analysis combined with ultraviolet visible spectrophotometry (FIA-UV) method can eliminate interference due to trace elements in the extraction solution, as well as effectively improving accuracy and reliability for the determination of aniline in chrome-free leather extraction solution.
RESUMO
The low hydrothermal stability of the raw collagen restricts its usage. To improve the hydrothermal stability of collagen, two kinds of materials with weak astringency were used by experts. The research proved that the synergistic effect was formed during the process. In this study, by using UV, FT-IR, 13CNMR spectra and elemental analysis on the salicylic acid and metal-salicylic complexes, we could get the structural formula of every compound. And then, the hide powder was treated with the compounds. At last, the treated hide powder was tested by DSC. It could be presumed that the Rigid Matrix formed between the collagen doses can increase the hydrothermal stability of raw collagen, The result indicated that salicylic-chrome with large stable constant was better than others in improving the heat resistance of raw collagen, and the denaturalization temperature of hide powder treated with salicylic-chrome was 146.7 degrees C. Salicylic-aluminum was in the second place, the relevant temperature being 145.7 degrees C.
