| Near-infrared spectroscopy (NIRS) is an efficient and fast analytical technique. Near infrared spectroscopy consists of frequency doubling and combination band of molecular vibration spectrum, but frequency doubling and combination band of molecular vibration spectrum in NIR zone is weak, band is complex and overlay. So NIRS is a technique of weak signal and multivariate information. With the development of optical, electronics technology and computer software and hardware technique in last decade, theory and technique of weak signal processing in analytical chemistry is farther more mature, research and application of NIRS has developed rapidly, NIRS has been generally accepted by scientific researches and official. Advantages of NIRS are quick, no pre-processing, simultaneous determination, non-destructive, unpolluted. These advantages have made NIRS used in Agriculture, petrochemical, Pharmaceutical, Food Processing.Under the support of Chongqing Science and Technology Commission program (CSTC2008EA5008), this thesis studies on analysis and application of simultaneous determination in different fields by NIRS:1.Simultaneous determination of chlorogenic acid and baicalin in Heat-clearing and Detoxicating Oral Liquid by near infrared spectroscopy, prediction results are accurate and reliable. This method can be applied in rapid analysis of Heat-clearing and Detoxicating Oral Liquid, and it is fit for on-line detection and has a wind application prospect; 2. Simultaneous determination of chlorogenic acid and baicalin in Yinhuang granules by near infrared spectroscopy, the model of solid preparations of traditional Chinese medicine had been set, and the resonance peaks of spectrum was researched; 3.Determination of Coptis chinensis'quality by near infrared spectroscopy, the Coptis chinensis of Shizhu was inspected by NIRS. Building models from calibration set and validation set for prediction set obtained the better results, this model could be extended to determination of the related products of Coptis chinensis, which is of great explored potentiality and utilized value; 4. Simultaneous determination of maltose, lactose and sucrose in aqueous solution by short-wavelength near infrared spectroscopy, the model could be applied in drinks;5.Simultaneous determination of melamine and formaldehyde in aqueous solution by short-wavelength near infrared spectroscopy, determination of melamine plastic was researched. 1.Simultaneous determination of chlorogenic acid and baicalin in Heat-clearing and Detoxicating Oral Liquid by near infrared spectroscopyThe calibration model for simultaneous determination of chlorogenic acid and baicalin in Heat-clearing and Detoxicating Oral Liquid was built by partial least squares and near infrared spectroscopy,and discuss the method of spectral pretreatment. Building models from calibration set and validation for prediction set obtained the better results. According to Heat-clearing and Detoxicating Oral Liquid from 30 batches of 6 factory, the correlation coefficient of chlorogenic acid and baicalin model are 0.9993 and 0.9923,RMSECV are 0.467 and 0.480. The correlation coefficients in prediction set are 0.9997 and 0.9969, prediction results are accurate and reliable. This method can be applied in rapid analysis of Heat-clearing and Detoxicating Oral Liquid, and it is fit for on-line detection and has a wind application prospect.2. Simultaneous determination of chlorogenic acid and baicalin in Yinhuang granules by near infrared spectroscopyChlorogenic acid and baicalin in Yinhuang granules were determined by near infrared spectroscopy in this experiment, resonance peaks of spectrum was researched, and discuss the method of spectral pretreatment. Building models from calibration set and validation for prediction set obtained the better results. According to Yinhuang granules, the correlation coefficient of chlorogenic acid and baicalin model are 0.9324 and 0.9263,RMSECV are 0.234 and 0.198. The correlation coefficients in prediction set are 0.9300 and 0.9279, RMSEP are 0.108 and 0.094, prediction results are accurate and reliable. This method can be applied in rapid analysis of Yinhuang granules.3. Determination of Coptis chinensis' quality by near infrared spectroscopyThe calibration model for Determination of Coptis chinensis' quality was built by partial least squares and near infrared spectroscopy,and discuss the method of spectral pretreatment. Building models from calibration set and validation set for prediction set obtained the better results. According to the model of calibration set, The correlation coefficients are 0.9298 and 0.8898, RMSECV are 0.239 and 0.00302. The correlation coefficients in prediction set are 0.9347 and 0.9146, RMSEP are 0.104 and 0.0033,prediction results are accurate and reliable. This method can be applied in rapid analysis of Coptis chinensis. The method is suitable for production fields and circulation fields, and has a wide application prospect. The experiment also proves that this model could be extended to determination of the related products of Coptis chinensis, which is of great explored potentiality and utilized value.4. Simultaneous determination of maltose, lactose and sucrose in aqueous solution by short-wavelength near infrared spectroscopyThe calibration model for simultaneous determination of maltose,lactose and sucrose in aqueous solution was built by partial least squares and short-wavelength near infrared spectroscopy (800-1100 nm),and discuss the method of spectral pretreatment. Building models from calibration set and validation for prediction set obtained the better results. For concentrations of maltose, lactose and sucrose in the ranges of 10-60 mg.L"1,2-12 mg.L-1,10-60 mg.L-1,the correlation coefficient in the calibration set are 0.9904,0.9971 and 0.9926 respectively, RMSECV are 0.0213,0.2525 and 0.1859, and the relative standard deviations in the prediction set are 3.54%, 3.55%,3.32%,respectively. In application, it makes initial exploration of models in actual samples. The advantages of the method are simple and effective, with low cost for the simultaneous5. Simultaneous determination of melamine and formaldehyde in aqueous solution by short-wavelength near infrared spectroscopyThe calibration model for simultaneous determination of melamine and formaldehyde in aqueous solution was built by partial least squares and short-wavelength near infrared spectroscopy (800-1100 nm), and discuss the method of spectral pretreatment. Building models from calibration set and validation for prediction set obtained the better results. For concentrations of melamine and formaldehyde in the ranges of 0-3.58 mg.L-1,0-8.02 mg.L-1,the correlation coefficient in the calibration set are 0.9996,0.9950 respectively, RMSECV are 0.170,0.223.In application, it makes initial exploration of models in actual samples. The advantages of the method are simple and effective, with low cost for the simultaneous determination of multi-component system. It may be applied in practice easily.
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