Sponsored by college of chemistry and molecular engineering, Peking University and Thermo Fisher Scientific, The Asian Regional Conference on 2DCOS （2DCOS-2014） was held （19, April, 2014 - 20, April, 2014） at the ...Sponsored by college of chemistry and molecular engineering, Peking University and Thermo Fisher Scientific, The Asian Regional Conference on 2DCOS （2DCOS-2014） was held （19, April, 2014 - 20, April, 2014） at the beautiful campus of Peking University. Prof. lsao Noda,展开更多
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
The complex and diverse environments of Lanxangia tsaoko(LT)have given rise to a wide range of fruit types,however,there are some differences in chemical information between the different fruit types.The phenotypic da...The complex and diverse environments of Lanxangia tsaoko(LT)have given rise to a wide range of fruit types,however,there are some differences in chemical information between the different fruit types.The phenotypic data in this study showed that dry weight and long axis length are somewhat positively correlated with soluble sugar.Further UPLC-MS/MS-based broadly targeted metabolomics results showed that phenolic acids,flavonoids,amino acids and derivatives,terpenoids,and alkaloids differed most among the seven fruit types.Using fourier transform near-infrared spectroscopy(FT-NIRS)and two-dimensional correlation spectroscopy(2DCOS)to characterize the chemical composition of different fruit types of LT and the 5400-4000 cm1 region was identified as the characteristic band for the different fruit types.Subsequently,three identification models,support vector machine(SVM),partial least squares discriminant analysis(PLS-DA),residual convolutional neural network(ResNet),were established in the fruit type recognition all show excellent performance.In particular,ResNet.The accuracies of synchronized 2DCOS images in full and single bands(10000-7600 cm^(-1),7600-5400 cm^(-1) and 5400-4000 cm^(-1))are 100%for both training and test sets.Compared to traditional machine learning models,ResNet does not require complex preprocessing and is a potentially fast way to identify different fruit types in LT.Finally,a partial least squares regression(PLSR)model was developed to predict soluble sugars and soluble proteins in LT with optimal RPD values of 1.5393 and 1.4649,respectively.展开更多
Biochar-derived dissolved organic matter(DOM)is a highly active component that plays a critical and complex role in the immobilization of heavy metals.This study systematically investigated the impact of DOM on Pb(Ⅱ)...Biochar-derived dissolved organic matter(DOM)is a highly active component that plays a critical and complex role in the immobilization of heavy metals.This study systematically investigated the impact of DOM on Pb(Ⅱ)adsorption by comparing the adsorption capacities of biochar before and after DOM removal,thereby unveiling the underlying mechanisms through advanced spectroscopic techniques.Adsorption experiments demonstrated that water-washed biochar(WBC)exhibited a markedly reduced adsorption capacity(35.0 mg g^(−1))compared to untreated biochar(BC)(96.2 mg g^(−1)),highlighting the essential role of DOM in enhancing Pb(Ⅱ)adsorption.Kinetic and isothermal analyses revealed that the adsorption process was predominantly chemical in nature,as evidenced by the excellent fit of experimental data to the pseudo-second-order,Freundlich,and Temkin models.FTIR and XPS analyses confirmed that oxygen-containing functional groups,including hydroxyl,carboxyl,carbonyl,and ether groups,actively participated in Pb(Ⅱ)complexation in BC,WBC,and DOM.Spectral shifts and changes in the relative abundance of C–O and C=O bonds further supported this conclusion.The Pb 4f spectra indicated that Pb(Ⅱ)was primarily retained as Pb_(3)(OH)_(2)(CO_(3))_(2),with complexation identified as the dominant mechanism,followed by co-precipitation.UV differential log-transformed absorption spectra derived from titration experiments,revealed the heterogeneity of Pb(Ⅱ)binding sites within DOM.Furthermore,excitation-emission matrix fluorescence spectroscopy coupled with parallel factor analysis(EEM-PARAFAC)identified three humic-like components.Among these,component C3(humic-like and tyrosine substance)exhibited the strongest binding affinity for Pb(Ⅱ).Hetero-2DCOS analysis,combined with additional spectroscopic techniques,demonstrated that carboxyl groups in humic-like substances were the most reactive sites for Pb(Ⅱ)binding.These findings provide molecular-level insights into the structural and functional characteristics of biochar-derived DOM-Pb(Ⅱ)complexes,offering a scientific basis for optimizing biochar-based strategies for heavy metal pollution remediation.展开更多
Particles of aerodynamic diameter〈2.5 pm （PM/.5） caused extremely severe and persistent haze pollution is of concern in many cities. In this study, samples of PM2.5 were collected from atmosphere environment of Bei...Particles of aerodynamic diameter〈2.5 pm （PM/.5） caused extremely severe and persistent haze pollution is of concern in many cities. In this study, samples of PM2.5 were collected from atmosphere environment of Beijing and Shanxi Province, and analyzed using terahertz （THz） radiation. The transmission spectrum of PM2.5 in Shanxi Province had two distinct absorption peaks at 6.0 and 6.7 THz, and the curve was increasing on the whole. However, the transmission spectrum of PMa.5 in Beijing had obviously different variation tendency and the absorption peak was studied by monitoring PM2.5 masses in conjunction with two-dimensional correlation spectro- scopy （2DCOS）. By comparing the pollutant species and concentrations of Shanxi Province and Beijing over the time of collecting samples, the concentrations of sulfate and ammonium were similar, which contributed to emerge absorption bands in the same position. While the concentrations of organic matter （OM）, nitrate, chloride and elemental carbon （EC） were different. Furthermore, dust and some other inorganic ion are unique to Shanxi province, which lead to different variation tendency of the transmission spectrum of PM2.5. These results will be of importance for environmental monitoring and for control- ling PM emissions. According to this research, optical techniques, and especially spectral methods, should be considered for PM2.5 monitoring.展开更多
Gastrodia elata Blume(G.elata Bl.),with its excellent nutritional and medicinal value from Zhaotong,has been protected by geographical indication(GI).Accurate certification of its origin is a prerequisite to safeguard...Gastrodia elata Blume(G.elata Bl.),with its excellent nutritional and medicinal value from Zhaotong,has been protected by geographical indication(GI).Accurate certification of its origin is a prerequisite to safeguard consumer interests and maintain the market.Four different regions and three varieties of G.elata Bl.from Zhaotong were used in this study(n=262).Tri-step infrared spectroscopy was used for ATR-FTIR spectral analysis to filter out fingerprint regions for data fusion with FT-NIR spectra,after which conventional discriminant models(PLS-DA and GS-SVM)were built.The second derivative(SD),multiple scattering correction(MSC),and Savitzky-Golay(SG)preprocessing were also performed on the spectra,and it was found that the preprocessing improved the performance of the PLS-DA model.The optimal model results in GS-SVM,based on mid-level data fusion of principal components(PCs)and latent variables(LVs),with sensitivity,specificity,accuracy,and Matthews correlation coefficient(MCC)of 1 for the test set.Furthermore,the residual convolutional neural network(ResNet)models were built,based on FT-NIR full spectra,band 36002700 cm^(-1)(MFA)and band 1750500 cm^(-1)(MFB).Their accuracy in both train and test sets exceeds 97%,and the loss function curve is close to 0,which indicates that these three bands can be used as a fingerprint area to verify the GI of Zhaotong G.elata Bl.This study provides a fast,non-invasive method for the authentication of food or medicinal plant GI.展开更多
文摘Sponsored by college of chemistry and molecular engineering, Peking University and Thermo Fisher Scientific, The Asian Regional Conference on 2DCOS （2DCOS-2014） was held （19, April, 2014 - 20, April, 2014） at the beautiful campus of Peking University. Prof. lsao Noda,
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.
基金supported by Science and Technology Special Project for Rural Revitalisation-Science and Technology Mission(Team):Yunnan Province Border Village Science and Technology Special Mission Team(Grant number:202304BI090032)Yunnan Provincial Major Science and Technology Special Project-Nujiang Lanxangia tsao-ko Industry Science and Technology Innovation and Application Research(Grant number:202202AE090035).
文摘The complex and diverse environments of Lanxangia tsaoko(LT)have given rise to a wide range of fruit types,however,there are some differences in chemical information between the different fruit types.The phenotypic data in this study showed that dry weight and long axis length are somewhat positively correlated with soluble sugar.Further UPLC-MS/MS-based broadly targeted metabolomics results showed that phenolic acids,flavonoids,amino acids and derivatives,terpenoids,and alkaloids differed most among the seven fruit types.Using fourier transform near-infrared spectroscopy(FT-NIRS)and two-dimensional correlation spectroscopy(2DCOS)to characterize the chemical composition of different fruit types of LT and the 5400-4000 cm1 region was identified as the characteristic band for the different fruit types.Subsequently,three identification models,support vector machine(SVM),partial least squares discriminant analysis(PLS-DA),residual convolutional neural network(ResNet),were established in the fruit type recognition all show excellent performance.In particular,ResNet.The accuracies of synchronized 2DCOS images in full and single bands(10000-7600 cm^(-1),7600-5400 cm^(-1) and 5400-4000 cm^(-1))are 100%for both training and test sets.Compared to traditional machine learning models,ResNet does not require complex preprocessing and is a potentially fast way to identify different fruit types in LT.Finally,a partial least squares regression(PLSR)model was developed to predict soluble sugars and soluble proteins in LT with optimal RPD values of 1.5393 and 1.4649,respectively.
基金supported by the National Key R&D Program of China(2024YFD1501700)the Distinguished Youth Science Foundation of Heilongjiang Province,China(JQ2023E001)the Young Leading Talents Project of Northeast Agricultural University,China(NEAU2023QNLJ-013,NEAU2024QNLJ-01).
文摘Biochar-derived dissolved organic matter(DOM)is a highly active component that plays a critical and complex role in the immobilization of heavy metals.This study systematically investigated the impact of DOM on Pb(Ⅱ)adsorption by comparing the adsorption capacities of biochar before and after DOM removal,thereby unveiling the underlying mechanisms through advanced spectroscopic techniques.Adsorption experiments demonstrated that water-washed biochar(WBC)exhibited a markedly reduced adsorption capacity(35.0 mg g^(−1))compared to untreated biochar(BC)(96.2 mg g^(−1)),highlighting the essential role of DOM in enhancing Pb(Ⅱ)adsorption.Kinetic and isothermal analyses revealed that the adsorption process was predominantly chemical in nature,as evidenced by the excellent fit of experimental data to the pseudo-second-order,Freundlich,and Temkin models.FTIR and XPS analyses confirmed that oxygen-containing functional groups,including hydroxyl,carboxyl,carbonyl,and ether groups,actively participated in Pb(Ⅱ)complexation in BC,WBC,and DOM.Spectral shifts and changes in the relative abundance of C–O and C=O bonds further supported this conclusion.The Pb 4f spectra indicated that Pb(Ⅱ)was primarily retained as Pb_(3)(OH)_(2)(CO_(3))_(2),with complexation identified as the dominant mechanism,followed by co-precipitation.UV differential log-transformed absorption spectra derived from titration experiments,revealed the heterogeneity of Pb(Ⅱ)binding sites within DOM.Furthermore,excitation-emission matrix fluorescence spectroscopy coupled with parallel factor analysis(EEM-PARAFAC)identified three humic-like components.Among these,component C3(humic-like and tyrosine substance)exhibited the strongest binding affinity for Pb(Ⅱ).Hetero-2DCOS analysis,combined with additional spectroscopic techniques,demonstrated that carboxyl groups in humic-like substances were the most reactive sites for Pb(Ⅱ)binding.These findings provide molecular-level insights into the structural and functional characteristics of biochar-derived DOM-Pb(Ⅱ)complexes,offering a scientific basis for optimizing biochar-based strategies for heavy metal pollution remediation.
文摘Particles of aerodynamic diameter〈2.5 pm （PM/.5） caused extremely severe and persistent haze pollution is of concern in many cities. In this study, samples of PM2.5 were collected from atmosphere environment of Beijing and Shanxi Province, and analyzed using terahertz （THz） radiation. The transmission spectrum of PM2.5 in Shanxi Province had two distinct absorption peaks at 6.0 and 6.7 THz, and the curve was increasing on the whole. However, the transmission spectrum of PMa.5 in Beijing had obviously different variation tendency and the absorption peak was studied by monitoring PM2.5 masses in conjunction with two-dimensional correlation spectro- scopy （2DCOS）. By comparing the pollutant species and concentrations of Shanxi Province and Beijing over the time of collecting samples, the concentrations of sulfate and ammonium were similar, which contributed to emerge absorption bands in the same position. While the concentrations of organic matter （OM）, nitrate, chloride and elemental carbon （EC） were different. Furthermore, dust and some other inorganic ion are unique to Shanxi province, which lead to different variation tendency of the transmission spectrum of PM2.5. These results will be of importance for environmental monitoring and for control- ling PM emissions. According to this research, optical techniques, and especially spectral methods, should be considered for PM2.5 monitoring.
基金supported by Special Program for the Major Science and Technology Projects of Yunnan Province[Grant Number:202202AE090001].
文摘Gastrodia elata Blume(G.elata Bl.),with its excellent nutritional and medicinal value from Zhaotong,has been protected by geographical indication(GI).Accurate certification of its origin is a prerequisite to safeguard consumer interests and maintain the market.Four different regions and three varieties of G.elata Bl.from Zhaotong were used in this study(n=262).Tri-step infrared spectroscopy was used for ATR-FTIR spectral analysis to filter out fingerprint regions for data fusion with FT-NIR spectra,after which conventional discriminant models(PLS-DA and GS-SVM)were built.The second derivative(SD),multiple scattering correction(MSC),and Savitzky-Golay(SG)preprocessing were also performed on the spectra,and it was found that the preprocessing improved the performance of the PLS-DA model.The optimal model results in GS-SVM,based on mid-level data fusion of principal components(PCs)and latent variables(LVs),with sensitivity,specificity,accuracy,and Matthews correlation coefficient(MCC)of 1 for the test set.Furthermore,the residual convolutional neural network(ResNet)models were built,based on FT-NIR full spectra,band 36002700 cm^(-1)(MFA)and band 1750500 cm^(-1)(MFB).Their accuracy in both train and test sets exceeds 97%,and the loss function curve is close to 0,which indicates that these three bands can be used as a fingerprint area to verify the GI of Zhaotong G.elata Bl.This study provides a fast,non-invasive method for the authentication of food or medicinal plant GI.
