The infrared absorption method for methane concentration detection is an ideal way to detect methane at present. However, it is difficult to spread this method due to its high cost. In this paper, by using a wideband ...The infrared absorption method for methane concentration detection is an ideal way to detect methane at present. However, it is difficult to spread this method due to its high cost. In this paper, by using a wideband infrared light emitting di- ode （LED） accompanied with a PIN photo electric diode, a low-cost methane detection system was designed. To overcome the shortcomings caused by the wide working band, a differential light path was designed. By means of a differential ratio algo- rithm, the stability and the accuracy of the system were guaranteed. Finally, the validity of the system with the proposed algo- rithm was verified by the experiment results.展开更多
The aim of the study was to describe the binding of cholic acid by hemicellulose and pectin of yard-long bean at gastrointestinal system （in vitro）, through variation of acidity （pH 3, 5 and 7） and boiling time （...The aim of the study was to describe the binding of cholic acid by hemicellulose and pectin of yard-long bean at gastrointestinal system （in vitro）, through variation of acidity （pH 3, 5 and 7） and boiling time （raw/0, 5, 20 and 35 minutes） of yard-long bean. Two-way Anova （α= 5%） and functional groups analysis by infrared spectrophotometer were applied for the binding description. The results of the study showed： （1） The highest binding percentage of cholic acid by dietary fiber of yard-long bean at pH 3-raw treatment （76.603%）; （2） Cholic acid binding via C = O/ester or acid of hemicellulose, C-O-C/cyclic ether of pectin, while C = O/ester or acid of oectin through iron.展开更多
The effect of a novel active nucleating agent(TBC8-eb) on the isothermal crystallization of poly(L-lactic acid) (PLLA) was studied by differential scanning calorimetry(DSC) and Fourier transform infrared spectroscopy(...The effect of a novel active nucleating agent(TBC8-eb) on the isothermal crystallization of poly(L-lactic acid) (PLLA) was studied by differential scanning calorimetry(DSC) and Fourier transform infrared spectroscopy(FTIR) . The analysis on kinetics demonstrates that TBC8-eb can not only accelerate the crystallization rate but also transform most of the original spherulite crystals of PLLA into sheaf-like crystals. Furthermore,the free energy of folding(σe) of PLLA and PLLA with TBC8-eb is 0.15 and 0.06 J·m-2,respectively,which suggests that the addition of TBC8-eb favors the regular folding of molecule chains in the crystallization of PLLA,improv-ing its crystallization rate. The FTIR results show that TBC8-eb can accelerate the conformational ordering of PLLA in the isothermal crystallization. The conformational ordering of PLLA nucleated with TBC8-eb begins with the interchain interaction of CH3,and then a short helix emerges where a couple of CH3 groups interact.展开更多
文摘The infrared absorption method for methane concentration detection is an ideal way to detect methane at present. However, it is difficult to spread this method due to its high cost. In this paper, by using a wideband infrared light emitting di- ode （LED） accompanied with a PIN photo electric diode, a low-cost methane detection system was designed. To overcome the shortcomings caused by the wide working band, a differential light path was designed. By means of a differential ratio algo- rithm, the stability and the accuracy of the system were guaranteed. Finally, the validity of the system with the proposed algo- rithm was verified by the experiment results.
文摘The aim of the study was to describe the binding of cholic acid by hemicellulose and pectin of yard-long bean at gastrointestinal system （in vitro）, through variation of acidity （pH 3, 5 and 7） and boiling time （raw/0, 5, 20 and 35 minutes） of yard-long bean. Two-way Anova （α= 5%） and functional groups analysis by infrared spectrophotometer were applied for the binding description. The results of the study showed： （1） The highest binding percentage of cholic acid by dietary fiber of yard-long bean at pH 3-raw treatment （76.603%）; （2） Cholic acid binding via C = O/ester or acid of hemicellulose, C-O-C/cyclic ether of pectin, while C = O/ester or acid of oectin through iron.
基金Supported by the National Natural Science Foundation of China （20876042） Program of Shanghai Subject Chief Scientist （10XD1401500） Research Fund for the Doctoral Program of Higher Education of China
文摘The effect of a novel active nucleating agent(TBC8-eb) on the isothermal crystallization of poly(L-lactic acid) (PLLA) was studied by differential scanning calorimetry(DSC) and Fourier transform infrared spectroscopy(FTIR) . The analysis on kinetics demonstrates that TBC8-eb can not only accelerate the crystallization rate but also transform most of the original spherulite crystals of PLLA into sheaf-like crystals. Furthermore,the free energy of folding(σe) of PLLA and PLLA with TBC8-eb is 0.15 and 0.06 J·m-2,respectively,which suggests that the addition of TBC8-eb favors the regular folding of molecule chains in the crystallization of PLLA,improv-ing its crystallization rate. The FTIR results show that TBC8-eb can accelerate the conformational ordering of PLLA in the isothermal crystallization. The conformational ordering of PLLA nucleated with TBC8-eb begins with the interchain interaction of CH3,and then a short helix emerges where a couple of CH3 groups interact.
