红外ATR光谱法(ATR-IR)用于山茶油中棕榈酸和十四烷酸含量的快速分析。配制了72个山茶油样本用于ATR光谱的采集,不同的光谱预处理方法用于光谱有效信息的提取,小波压缩(wavelet compression,WC)方法用于建模变量的优化,偏最小二乘回归(p...红外ATR光谱法(ATR-IR)用于山茶油中棕榈酸和十四烷酸含量的快速分析。配制了72个山茶油样本用于ATR光谱的采集,不同的光谱预处理方法用于光谱有效信息的提取,小波压缩(wavelet compression,WC)方法用于建模变量的优化,偏最小二乘回归(partial least square,PLS)用于脂肪酸含量的定量分析模型的构建。结果表明,ATR光谱经小波导数(wavelet derivative,WD)―标准正态变量变换(standard normal variate,SNV)预处理后,棕榈酸模型的预测相关系数(correlation coefficient of prediction,Rp)和预测均方根误差(root mean square error of prediction,RMSEP)分别为由原始光谱的0.789和3.332改善为0.908和2.653;十四烷酸模型的Rp和RMSEP分别由0.870和0.087改善为0.948和0.058;建模变量经WC预处理后由原始光谱的2 500个分别减小为190和180个,为山茶油中脂肪酸含量的测定提供了一种简便快速的分析方法。展开更多
Fourier transform infrared attenuated total reflectance (FTIR-ATR) spectroscopy was employed to characterize rapeseed oils. The spectral features of rapeseed oils were first investigated. Spectral data was processed...Fourier transform infrared attenuated total reflectance (FTIR-ATR) spectroscopy was employed to characterize rapeseed oils. The spectral features of rapeseed oils were first investigated. Spectral data was processed using principal component analysis (PCA) and linear discriminant analysis (LDA) to discriminate the oils from three cultivars of rapeseeds. As a result, 100% discrimination accuracy was obtained by LDA. Furthermore, the applicability of FTIR-ATR spectroscopy to characterize the changes of rapeseed oils caused by thermal treatment was studied. The rapeseed oil at 60 ℃ was regularly subjected to spectral measurement, and the spectral changes induced by thermal treatment were analyzed and discussed. This study had demonstrated the good performance of FTIR-ATR spectroscopy in characterizing rapeseed oils.展开更多
Heparin was grafted onto polycarbonate urethane (PCU) surface via a three-step procedure utilizing α, ωdiamino-poly(ethylene glycol) (APEG, M n =2 000) as a spacer. In the first step, isocyanate functional groups we...Heparin was grafted onto polycarbonate urethane (PCU) surface via a three-step procedure utilizing α, ωdiamino-poly(ethylene glycol) (APEG, M n =2 000) as a spacer. In the first step, isocyanate functional groups were introduced onto PCU surface by the treatment of hexamethylene diisocyanate (HDI) in the presence of di-n-butyltin dilaurate (DBTDL) as a catalyst. In the second step, APEG was linked to the PCU surface to obtain the APEG conjugated PCU surface (PCU-APEG). In the third step, heparin was covalently coupled with PCU-APEG in the presence of N-hydroxysuccinimide (NHS) and 1-ethyl-3-(3-dimethylamidopropyl) carbodiimide (EDAC). The amount of heparin (1.639 μg/cm 2 ) covalently immobilized on the PCU-APEG surface was determined by the toluidine blue method. The modified surface was characterized by water contact angle, attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). The hemocompatibility was preliminarily studied by platelet adhesion test. The results indicated that heparin was successfully grafted onto the PCU surface, and meanwhile the hydrophilicity and hemocompatibility of the modified PCU surface were improved significantly compared with the blank PCU surface.展开更多
The aim of this present study is to investigate the effect of Zanthoxylum bungeanum oil (essential oil from Z. bungeanum Maxim.) on cytotoxicity and the transdermal permeation of 5-fluorouracil and indomethacin. The...The aim of this present study is to investigate the effect of Zanthoxylum bungeanum oil (essential oil from Z. bungeanum Maxim.) on cytotoxicity and the transdermal permeation of 5-fluorouracil and indomethacin. The cy- totoxicity of Z. bungeanum oil on dermal fibroblasts and epidermal keratinocytes was studied using an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The rat skin was employed to determine the percutaneous penetration enhancement effect of Z. bungeanum oil on hydrophilic and lipophilic model drugs, i.e., 5-fluorouracil and indomethacin. The secondary structure changes of the rat stratum comeum (SC) were determined using attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), and saturated solubilities and SC/vehicle partition coefficients of two model drugs with and without Z. bungeanum oil were also measured to un- derstand its related mechanisms of action. It was found that the half maximal inhibitory concentration (ICs0) values of Z. bungeanum oil were significantly lower in HaCaT and CCC-ESF-1 cell lines compared to the well-established and standard penetration enhancer Azone. The Z. bungeanum oil at various concentrations effectively facilitated the percutaneous penetration of two model drugs across the rat skin. In addition, the mechanisms of permeation en- hancement by Z. bungeanum oil could be explained with saturated solubility, SC/vehicle partition coefficient, and secondary structure changes of SC.展开更多
The catalytic performance of carbide slag in transesterification is investigated and the reaction kinetic parameters are calculated. After being activated at 650℃, calcium compounds of carbonate and hydroxide in the ...The catalytic performance of carbide slag in transesterification is investigated and the reaction kinetic parameters are calculated. After being activated at 650℃, calcium compounds of carbonate and hydroxide in the carbide slag are mainly transformed into calcium oxide. The activated carbide slag utilized as the transesterification catalyst is characterized by X-ray diffraction (XRD), attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), nitrogen adsorption-desorption and the Hammett indicator method. Compared with the carbide slag activated at 700 and 800℃, the largest surface area of 22.63 m2g^-1, the smallest particle size of 265.12 nm and the highest catalytic efficiency of the carbide slag activated at 650℃ guarantee its capacity in catalyzing transesterification. Then, the influences of activated temperature (Ta), molar ratio of methanol to oil (γ), catalyst added amount (ζ), reaction temperature (Tr) and reaction time (τ) on the catalytic performance are investi- gated. Under the optimal transesterification condition of Ta=650℃, γ=15, ζ=3%, Tr=60℃ and τ=-110 rain, the catalytic efficiency of 92.98% can be achieved. Finally, the kinetic parameters of transesterification catalyzed by the activated carbide slag are calculated, where activation energy (E) is 68.45 kJ mol^-1 and pre-exponential factor (k0) is 1.75×10^9 min^-1. The activated carbide slag shows better reused property than calcium hydroxide.展开更多
A simple approach has been developed to functionalize various substrates, such as gold and polyvinylchloride, with dopamine methacrylamide—a molecule with adhesive properties that mimic those of mussels—to produce a...A simple approach has been developed to functionalize various substrates, such as gold and polyvinylchloride, with dopamine methacrylamide—a molecule with adhesive properties that mimic those of mussels—to produce a versatile and general platform for subsequent surface modification. With active double bonds on the surface, various polymers, such as poly([2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl) ammonium hydroxide(PMEDSAH) and poly(N-vinylpyrrolidone)(PVP), can be grafted by conventional radical polymerization. Double bond surface functionalization and subsequent polymer grafting have been verified by static water contact angle, Fourier transform infrared–attenuated total reflectance(FTIR-ATR) spectroscopy and X-ray photoelectron spectroscopy(XPS) measurements. Protein adsorption assays showed that the polymermodified substrates have good protein-resistant properties. Considering the advantages of facility, versatility and substrate- independence, this method should be useful in designing functional interfaces for bioengineering applications.展开更多
文摘红外ATR光谱法(ATR-IR)用于山茶油中棕榈酸和十四烷酸含量的快速分析。配制了72个山茶油样本用于ATR光谱的采集,不同的光谱预处理方法用于光谱有效信息的提取,小波压缩(wavelet compression,WC)方法用于建模变量的优化,偏最小二乘回归(partial least square,PLS)用于脂肪酸含量的定量分析模型的构建。结果表明,ATR光谱经小波导数(wavelet derivative,WD)―标准正态变量变换(standard normal variate,SNV)预处理后,棕榈酸模型的预测相关系数(correlation coefficient of prediction,Rp)和预测均方根误差(root mean square error of prediction,RMSEP)分别为由原始光谱的0.789和3.332改善为0.908和2.653;十四烷酸模型的Rp和RMSEP分别由0.870和0.087改善为0.948和0.058;建模变量经WC预处理后由原始光谱的2 500个分别减小为190和180个,为山茶油中脂肪酸含量的测定提供了一种简便快速的分析方法。
文摘Fourier transform infrared attenuated total reflectance (FTIR-ATR) spectroscopy was employed to characterize rapeseed oils. The spectral features of rapeseed oils were first investigated. Spectral data was processed using principal component analysis (PCA) and linear discriminant analysis (LDA) to discriminate the oils from three cultivars of rapeseeds. As a result, 100% discrimination accuracy was obtained by LDA. Furthermore, the applicability of FTIR-ATR spectroscopy to characterize the changes of rapeseed oils caused by thermal treatment was studied. The rapeseed oil at 60 ℃ was regularly subjected to spectral measurement, and the spectral changes induced by thermal treatment were analyzed and discussed. This study had demonstrated the good performance of FTIR-ATR spectroscopy in characterizing rapeseed oils.
基金Supported by International Cooperation from Ministry of Science and Technology of China(No.2008DFA51170)Science and Technology Project of Tianjin Municipal Science and Technology Commission(No.08ZCKFSF03300)
文摘Heparin was grafted onto polycarbonate urethane (PCU) surface via a three-step procedure utilizing α, ωdiamino-poly(ethylene glycol) (APEG, M n =2 000) as a spacer. In the first step, isocyanate functional groups were introduced onto PCU surface by the treatment of hexamethylene diisocyanate (HDI) in the presence of di-n-butyltin dilaurate (DBTDL) as a catalyst. In the second step, APEG was linked to the PCU surface to obtain the APEG conjugated PCU surface (PCU-APEG). In the third step, heparin was covalently coupled with PCU-APEG in the presence of N-hydroxysuccinimide (NHS) and 1-ethyl-3-(3-dimethylamidopropyl) carbodiimide (EDAC). The amount of heparin (1.639 μg/cm 2 ) covalently immobilized on the PCU-APEG surface was determined by the toluidine blue method. The modified surface was characterized by water contact angle, attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). The hemocompatibility was preliminarily studied by platelet adhesion test. The results indicated that heparin was successfully grafted onto the PCU surface, and meanwhile the hydrophilicity and hemocompatibility of the modified PCU surface were improved significantly compared with the blank PCU surface.
基金supported by the National Natural Science Foundation of China(No.81073059)the Beijing Natural Science Foundation(No.7132127)the Innovative Research Team in Beijing University of Chinese Medicine(No.2011-CXTD-13),China
文摘The aim of this present study is to investigate the effect of Zanthoxylum bungeanum oil (essential oil from Z. bungeanum Maxim.) on cytotoxicity and the transdermal permeation of 5-fluorouracil and indomethacin. The cy- totoxicity of Z. bungeanum oil on dermal fibroblasts and epidermal keratinocytes was studied using an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The rat skin was employed to determine the percutaneous penetration enhancement effect of Z. bungeanum oil on hydrophilic and lipophilic model drugs, i.e., 5-fluorouracil and indomethacin. The secondary structure changes of the rat stratum comeum (SC) were determined using attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), and saturated solubilities and SC/vehicle partition coefficients of two model drugs with and without Z. bungeanum oil were also measured to un- derstand its related mechanisms of action. It was found that the half maximal inhibitory concentration (ICs0) values of Z. bungeanum oil were significantly lower in HaCaT and CCC-ESF-1 cell lines compared to the well-established and standard penetration enhancer Azone. The Z. bungeanum oil at various concentrations effectively facilitated the percutaneous penetration of two model drugs across the rat skin. In addition, the mechanisms of permeation en- hancement by Z. bungeanum oil could be explained with saturated solubility, SC/vehicle partition coefficient, and secondary structure changes of SC.
基金supported by the National Natural Science Foundation of China(Grant No.51206098)the Shandong Province Outstanding Young and Middle-Aged Scientists Research Award Fund(Grant No.BS2012NJ005)
文摘The catalytic performance of carbide slag in transesterification is investigated and the reaction kinetic parameters are calculated. After being activated at 650℃, calcium compounds of carbonate and hydroxide in the carbide slag are mainly transformed into calcium oxide. The activated carbide slag utilized as the transesterification catalyst is characterized by X-ray diffraction (XRD), attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), nitrogen adsorption-desorption and the Hammett indicator method. Compared with the carbide slag activated at 700 and 800℃, the largest surface area of 22.63 m2g^-1, the smallest particle size of 265.12 nm and the highest catalytic efficiency of the carbide slag activated at 650℃ guarantee its capacity in catalyzing transesterification. Then, the influences of activated temperature (Ta), molar ratio of methanol to oil (γ), catalyst added amount (ζ), reaction temperature (Tr) and reaction time (τ) on the catalytic performance are investi- gated. Under the optimal transesterification condition of Ta=650℃, γ=15, ζ=3%, Tr=60℃ and τ=-110 rain, the catalytic efficiency of 92.98% can be achieved. Finally, the kinetic parameters of transesterification catalyzed by the activated carbide slag are calculated, where activation energy (E) is 68.45 kJ mol^-1 and pre-exponential factor (k0) is 1.75×10^9 min^-1. The activated carbide slag shows better reused property than calcium hydroxide.
基金supported by the National Science Fund for Distinguished Young Scholars(21125418)the National Natural Science Foundation of China(21174098,21304062 and 21334004)+1 种基金the Natural Science Foundation of Jiangsu Higher Education Institutions of China(13KJB430020)the China Postdoctoral Science Foundation(2013M541714)
文摘A simple approach has been developed to functionalize various substrates, such as gold and polyvinylchloride, with dopamine methacrylamide—a molecule with adhesive properties that mimic those of mussels—to produce a versatile and general platform for subsequent surface modification. With active double bonds on the surface, various polymers, such as poly([2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl) ammonium hydroxide(PMEDSAH) and poly(N-vinylpyrrolidone)(PVP), can be grafted by conventional radical polymerization. Double bond surface functionalization and subsequent polymer grafting have been verified by static water contact angle, Fourier transform infrared–attenuated total reflectance(FTIR-ATR) spectroscopy and X-ray photoelectron spectroscopy(XPS) measurements. Protein adsorption assays showed that the polymermodified substrates have good protein-resistant properties. Considering the advantages of facility, versatility and substrate- independence, this method should be useful in designing functional interfaces for bioengineering applications.