A number of useful techniques associated with two-dimensional correlation spectroscopy(2DCOS)to improve its performance and utility have been developed in the last 30years.Evolution of these 2DCOS techniques,including...A number of useful techniques associated with two-dimensional correlation spectroscopy(2DCOS)to improve its performance and utility have been developed in the last 30years.Evolution of these 2DCOS techniques,including some of the very recent developments,is reviewed with examples.Topics include merged or modified asynchronous 2Dcorrelation spectrum,two-dimensional codistribution spectroscopy(2DCDS),Pareto scaling,and null-space projection treatment of spectral dataset.展开更多
A series of soy protein isolate(SPI)films plasticized by glycerol(Gly)were studied using attenuated total reflectance-Fourier transform infrared spectroscopy(ATR/FTIR).Perturbation-correlation movingwindow two-dimensi...A series of soy protein isolate(SPI)films plasticized by glycerol(Gly)were studied using attenuated total reflectance-Fourier transform infrared spectroscopy(ATR/FTIR).Perturbation-correlation movingwindow two-dimensional(PCMW2D)and two-dimensional correlation(2DCOS)analyses were applied to the amideⅠband and thus the hydrogen bond interaction between SPI and Gly was systematically investigated.When Gly concentrations were in the range 0~35%,the hydrogen bond amongβ-sheets was replaced by the one between SPI chain and Gly molecule,which caused these protein chains being changed toα-helix.However,the transformation ofβ-sheet toα-helix was saturated and both of them tend to change to random coil when Gly concentrations were in the range 35%~60%.展开更多
Aim:The fast and nondestructive identification of Cortex Periplocae and Cortex Acanthopanacis by Fourier transform near infrared spectroscopy and generalized two-dimensional(2D) correlation spectroscopy were perform...Aim:The fast and nondestructive identification of Cortex Periplocae and Cortex Acanthopanacis by Fourier transform near infrared spectroscopy and generalized two-dimensional(2D) correlation spectroscopy were performed.Methods:Near infrared spectra of Cortex Periplocae and Cortex Acanthopanacis was used for computation of the 2D correlation spectra and comparison of the synchronous and asynchronous 2D correlation spectra.Results:Two of the analytes had similar spectral characteristics in one-dimensional near infrared while quite different in 2D correlation spectra.Cortex Periplocae and Cortex Acanthopanacis were identified visually using the 2D correlation spectra in region 5 600~4 700 cm-1and 7 200~6 600 cm-1.Conclusion:The results prove that 2D correlation spectra could enhance the resolution of near infrared spectra and increase the capacity of identification.The combination of 2D correlation spectroscopy and near infrared spectroscopy allow a new and convenient approach for evaluating the medicinal herbs.展开更多
文摘A number of useful techniques associated with two-dimensional correlation spectroscopy(2DCOS)to improve its performance and utility have been developed in the last 30years.Evolution of these 2DCOS techniques,including some of the very recent developments,is reviewed with examples.Topics include merged or modified asynchronous 2Dcorrelation spectrum,two-dimensional codistribution spectroscopy(2DCDS),Pareto scaling,and null-space projection treatment of spectral dataset.
文摘A series of soy protein isolate(SPI)films plasticized by glycerol(Gly)were studied using attenuated total reflectance-Fourier transform infrared spectroscopy(ATR/FTIR).Perturbation-correlation movingwindow two-dimensional(PCMW2D)and two-dimensional correlation(2DCOS)analyses were applied to the amideⅠband and thus the hydrogen bond interaction between SPI and Gly was systematically investigated.When Gly concentrations were in the range 0~35%,the hydrogen bond amongβ-sheets was replaced by the one between SPI chain and Gly molecule,which caused these protein chains being changed toα-helix.However,the transformation ofβ-sheet toα-helix was saturated and both of them tend to change to random coil when Gly concentrations were in the range 35%~60%.
文摘Aim:The fast and nondestructive identification of Cortex Periplocae and Cortex Acanthopanacis by Fourier transform near infrared spectroscopy and generalized two-dimensional(2D) correlation spectroscopy were performed.Methods:Near infrared spectra of Cortex Periplocae and Cortex Acanthopanacis was used for computation of the 2D correlation spectra and comparison of the synchronous and asynchronous 2D correlation spectra.Results:Two of the analytes had similar spectral characteristics in one-dimensional near infrared while quite different in 2D correlation spectra.Cortex Periplocae and Cortex Acanthopanacis were identified visually using the 2D correlation spectra in region 5 600~4 700 cm-1and 7 200~6 600 cm-1.Conclusion:The results prove that 2D correlation spectra could enhance the resolution of near infrared spectra and increase the capacity of identification.The combination of 2D correlation spectroscopy and near infrared spectroscopy allow a new and convenient approach for evaluating the medicinal herbs.