水的拉曼光谱信噪比及水分子振动分析研究
时间:2018-05-05 21:02 来源:毕业论文 作者:毕业论文 点击:次
| 本文通过用光谱仪分别检测获取自来水、饮用瓶装水和超纯水的拉曼光谱，着重研究分析了 2700～3900 cm-1范围内水的宽峰特征拉曼谱线数据，依次提取曲线的峰值、左右基线值、左右峰高差、峰值信噪比、基线高差、基线高比、一阶导数、二阶导数等数值，并进行信噪比分析以及导数和高斯分解分析。结果表明，就本文所检测研究的实验样品，在 2700～3900 cm-1 范围内，（1）饮用瓶装水和超纯水的拉曼光谱峰值信噪比数值比自来水的相应数值大 2 倍以上；（2）自来水和白开水以及怡宝水的拉曼光谱左右基线的差值小于0，其他水样大于 0，并且，自来水和白开水的差值的绝对值比其他水样大 3 倍以上。上述结果表明：拉曼光谱的峰值信噪比、基线高差和基线高比都可以作为量化的指标，能有效鉴别区分饮用瓶装水与自来水；并且，峰值信噪比和基线高差这两个指标可以相互参照与佐证，同时使用能有效提高其鉴别的可信度。分析认为，相比于饮用瓶装水和超纯水，自来水中含有较多胶体颗粒杂质，其丁达尔光散射相应较大，导致其拉曼光谱曲线的基线显著抬升，这是自来水拉曼光谱的峰值信噪比显著小于饮用瓶装水和超纯水的主要原因。22271 此外，对水样的拉曼光谱曲线进行导数分析，进而进行高斯分解分析，各种水样高斯分解后的基元数目、基元中心位置等表现极其相似，反映了自来水与饮用瓶装水在水分子振动方面的一致性，表明自来水也是比较洁净的水。 毕业论文关键词： 拉曼光谱；水；信噪比；振动谱Title The Raman Spectra of Signal-to-noise Ratio and Water Molecular Vibration Analysis Abstract The Raman Spectra of tap water,drinking bottled water and ultrapure water have been tested and acquired by spectrometer. In this experiment ,curvilinear peak value,baseline value of the left and right,the height difference of peak value of the left and right,peak signal to noise ratio(PSNR),the height difference of baseline value,the height ratio of baseline value and other values are successively extracted from Raman spectral data of broad peak characteristic of water which is from 2700 to 3900 cm-1 .Then, a comparative analysis is performed of the corresponding values term by term.The following conclusions can be drawn.(1): Raman spectrum of peak signal to noise ratio value of drinking bottled water and ultrapure water is 2 times greater than tap water (2) Tap water and water and diet treasure water around the Raman spectra of the difference between the baseline value less than zero, other sample is greater than zero, and the absolute value of difference between tap water and water more than three times larger than the other samples. The results show that PSNR,the height difference of baseline and the height ratio of baseline can be as quantitative indices which are able to identify drinking bottled water with tap water;Besides PSNR and the height difference of baseline are reciprocal references and evidences,so using the two indices at the same time improves the credibility of identifying effectively。 Analysis, compared to drinking bottled water and ultrapure water, tap water contains more colloid particle impurities，Ding light scattering corresponding larger， causing the Raman spectrum curve of the baseline rise significantly, is this tap water Raman spectrum peak signal-to-noise ratio was significantly less than the main cause of drinking bottled water and ultrapure water. In addition, Raman spectra derivative curve analysis of the water samples, and then gaussian decomposition analysis.All kinds of water samples show extremely similar, Reflect the tap water and the drinking bottled water in the consistency of the molecular (责任编辑：qin) |