3-Nitro-1,2,4-triazol-5-one(NTO)is a typical high-energy,low-sensitivity explosive,and accurate concentration monitoring is critical for crystallization process control.In this study,a high-precision quantitative anal...3-Nitro-1,2,4-triazol-5-one(NTO)is a typical high-energy,low-sensitivity explosive,and accurate concentration monitoring is critical for crystallization process control.In this study,a high-precision quantitative analytical model for NTO concentration in ethanol solutions was developed by integrating real-time ATR-FTIR spectroscopy with chemometric and machine learning techniques.Dynamic spectral data were obtained by designing multi-concentration gradient heating-cooling cycle experiments,abnormal samples were eliminated using the isolation forest algorithm,and the effects of various preprocessing methods on model performance were systematically evaluated.The results show that partial least squares regression(PLSR)exhibits superior generalization ability compared to other models.Vibrational bands corresponding to C=O and–NO_(2)were identified as key predictors for concentration estimation.This work provides an efficient and reliable solution for real-time concentration monitoring during NTO crystallization and holds significant potential for process analytical applications in energetic material manufacturing.展开更多
Comparison of the ATR-FITR spectra of nature and artificial leather shows that their feature peak positions do not overlap,By analysing their spectra and their corresponding second derivative infrared spectra we can d...Comparison of the ATR-FITR spectra of nature and artificial leather shows that their feature peak positions do not overlap,By analysing their spectra and their corresponding second derivative infrared spectra we can discriminate them easily.Analysis and discrimination of leather products by ATR-FTIR is an accurate,sensitive,quick method.展开更多
The mechanism of enhancers (methanol,chloroform,azone and thiozone) was studied in vitro in mouse stratum corneum (SC).Attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR) was applied ...The mechanism of enhancers (methanol,chloroform,azone and thiozone) was studied in vitro in mouse stratum corneum (SC).Attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR) was applied to monitor the wavenumber shifts of CH2 stretching absorbance as well as the lipid content in the SC,which were used as criteria to explain the effect of the enhancers on mouse SC.The FTIR spectra record that treatment with these four enhancers would result in significant shifts toward higher wavenumber at vasCH2 and vsCH2 and the integration areas of vasCH2 and vsCH2 decrease when treatment of methanol and choloroform.It is concluded that these four enhancers could increase the gauche conformational isomer content of lipid CH2,made the lipid in the SC a more fluid state,thus the resistance of drug transdermal delivery was reduced.展开更多
To consider the reliability and performance of electronic devices based on polyimide derivatives, dynamic water sorption and diffusion behavior in a polyimide derivative: poly(4'4 oxydiphenylene pyromellitimide) ...To consider the reliability and performance of electronic devices based on polyimide derivatives, dynamic water sorption and diffusion behavior in a polyimide derivative: poly(4'4 oxydiphenylene pyromellitimide) (PMDA-ODA)/silica nanocomposite was investigated by two-dimensional ATR-FTIR spectroscopy, by which three states of water molecules owning different H-bonding strength were distinguished. The amounts and strength of H-bonding also played a significant role in determining the diffusion rate of the different states of water molecules. The type of aggregated water molecules which also formed H-bonding with silicic acid (residues) or polyimide system was the last one diffusing to the polymer side in contact with the ATR crystal element because the polymeric matrix blocked their diffusion to a great extent. The diffusion coefficient was also estimated to gain the information of the dynamic diffusion behavior.展开更多
基金supported by the Aeronautical Science Foundation of China(Grant No.20230018072011)。
文摘3-Nitro-1,2,4-triazol-5-one(NTO)is a typical high-energy,low-sensitivity explosive,and accurate concentration monitoring is critical for crystallization process control.In this study,a high-precision quantitative analytical model for NTO concentration in ethanol solutions was developed by integrating real-time ATR-FTIR spectroscopy with chemometric and machine learning techniques.Dynamic spectral data were obtained by designing multi-concentration gradient heating-cooling cycle experiments,abnormal samples were eliminated using the isolation forest algorithm,and the effects of various preprocessing methods on model performance were systematically evaluated.The results show that partial least squares regression(PLSR)exhibits superior generalization ability compared to other models.Vibrational bands corresponding to C=O and–NO_(2)were identified as key predictors for concentration estimation.This work provides an efficient and reliable solution for real-time concentration monitoring during NTO crystallization and holds significant potential for process analytical applications in energetic material manufacturing.
文摘Comparison of the ATR-FITR spectra of nature and artificial leather shows that their feature peak positions do not overlap,By analysing their spectra and their corresponding second derivative infrared spectra we can discriminate them easily.Analysis and discrimination of leather products by ATR-FTIR is an accurate,sensitive,quick method.
文摘The mechanism of enhancers (methanol,chloroform,azone and thiozone) was studied in vitro in mouse stratum corneum (SC).Attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR) was applied to monitor the wavenumber shifts of CH2 stretching absorbance as well as the lipid content in the SC,which were used as criteria to explain the effect of the enhancers on mouse SC.The FTIR spectra record that treatment with these four enhancers would result in significant shifts toward higher wavenumber at vasCH2 and vsCH2 and the integration areas of vasCH2 and vsCH2 decrease when treatment of methanol and choloroform.It is concluded that these four enhancers could increase the gauche conformational isomer content of lipid CH2,made the lipid in the SC a more fluid state,thus the resistance of drug transdermal delivery was reduced.
基金supported by the National Natural Science Foundation of China(No.20573022,No.20425415)the National Basic Research Pro-gram of China(2005CB623800),the PHD Program of M0E(20050246010)the"Qimingxing"Project(No.04QM1402)of Shanghai Municipal Science and Technology Commission,and the"Shuguang"Project(No.01SG05)of the Shanghai Municipal Education Commission and Shanghai Education Development Foundation.
文摘To consider the reliability and performance of electronic devices based on polyimide derivatives, dynamic water sorption and diffusion behavior in a polyimide derivative: poly(4'4 oxydiphenylene pyromellitimide) (PMDA-ODA)/silica nanocomposite was investigated by two-dimensional ATR-FTIR spectroscopy, by which three states of water molecules owning different H-bonding strength were distinguished. The amounts and strength of H-bonding also played a significant role in determining the diffusion rate of the different states of water molecules. The type of aggregated water molecules which also formed H-bonding with silicic acid (residues) or polyimide system was the last one diffusing to the polymer side in contact with the ATR crystal element because the polymeric matrix blocked their diffusion to a great extent. The diffusion coefficient was also estimated to gain the information of the dynamic diffusion behavior.