Polypropene （PP） plastics can be effectively degraded by natural volatile con- stituents from Ledum palustre catalyzed by atmospheric air dielectric barrier （DBD） plasma. The electron spin resonance （ESR） result...Polypropene （PP） plastics can be effectively degraded by natural volatile con- stituents from Ledum palustre catalyzed by atmospheric air dielectric barrier （DBD） plasma. The electron spin resonance （ESR） result indicates that the volatile constituents produce radicals in aerobic condition energized by power sources such as light, UV, plasma and so on. The degradation is a novel chemically oxidative way and it is initiated by a series of radical reactions. Lots of active cud oxidative species, radicals, products cud high euergy electromagnetic field in plasma aggravate the degradation process. The results about PP maximum tensile strength （Crbmax） confirm this conclusion. PP plastic heavily loses its extensibility, mechanical integrity and strength in a short time after suffering a synergetic treatment of the herb extract and air DBD plasma with no toxic residues left. The components of herb extract keep almost unchanged and may be reused. This study offers a new approach to manage and recycle typical plastics.展开更多
This study was conducted to evaluate the diurnal effect on essential oil yield and composition of Ledum palustre L. grown in northern Inner Mongolia, China. Essential oil content and composition were determined and co...This study was conducted to evaluate the diurnal effect on essential oil yield and composition of Ledum palustre L. grown in northern Inner Mongolia, China. Essential oil content and composition were determined and compared as a function of different harvesting times viz. 7:00 AM, 11:00 AM, 3:00 PM, 7:00 PM, and 11:00 PM within a day. The essential oil obtained by hydrodistillation was investigated by gas chromatography-mass spectrometry (GC-MS). The yield of essential oil was varied from 1.21% to 1.62%;the maximum oil yield was obtained at 3:00 PM and the minimum at 7:00 PM. Similar to oil yield, qualitative difference in essential oil composition of L. palustre was observed. For the best essential oil yields, L. palustre should be harvested during 11:00 AM to 3:00 PM.展开更多
A novel phenomenon of degradation ofpolypropylene plastic by volatile constituents of Ledum palustre is reported in this study. The characteristic ofdegradation is described by tensile strength, melting point,and scan...A novel phenomenon of degradation ofpolypropylene plastic by volatile constituents of Ledum palustre is reported in this study. The characteristic ofdegradation is described by tensile strength, melting point,and scanning electron micrographs as well as opticalmicrographs. The chemical composition of volatile oil ofLedum palustre is analyzed by gas chrography and massspectrometry. The mechanism of degradation and problemsneeded to be solved are also discussed.展开更多
基金supported by National Natural Science Foundation of China (No.20706060)Specialized Research Fund for the Doctoral Program of Higher Education of China (No.20070425515)+1 种基金Natural Science Foundation of Shandong Province,China (No.Q2007B06)PetroChina Innovation Foundation (No.07E1022)
文摘Polypropene （PP） plastics can be effectively degraded by natural volatile con- stituents from Ledum palustre catalyzed by atmospheric air dielectric barrier （DBD） plasma. The electron spin resonance （ESR） result indicates that the volatile constituents produce radicals in aerobic condition energized by power sources such as light, UV, plasma and so on. The degradation is a novel chemically oxidative way and it is initiated by a series of radical reactions. Lots of active cud oxidative species, radicals, products cud high euergy electromagnetic field in plasma aggravate the degradation process. The results about PP maximum tensile strength （Crbmax） confirm this conclusion. PP plastic heavily loses its extensibility, mechanical integrity and strength in a short time after suffering a synergetic treatment of the herb extract and air DBD plasma with no toxic residues left. The components of herb extract keep almost unchanged and may be reused. This study offers a new approach to manage and recycle typical plastics.
文摘This study was conducted to evaluate the diurnal effect on essential oil yield and composition of Ledum palustre L. grown in northern Inner Mongolia, China. Essential oil content and composition were determined and compared as a function of different harvesting times viz. 7:00 AM, 11:00 AM, 3:00 PM, 7:00 PM, and 11:00 PM within a day. The essential oil obtained by hydrodistillation was investigated by gas chromatography-mass spectrometry (GC-MS). The yield of essential oil was varied from 1.21% to 1.62%;the maximum oil yield was obtained at 3:00 PM and the minimum at 7:00 PM. Similar to oil yield, qualitative difference in essential oil composition of L. palustre was observed. For the best essential oil yields, L. palustre should be harvested during 11:00 AM to 3:00 PM.
文摘A novel phenomenon of degradation ofpolypropylene plastic by volatile constituents of Ledum palustre is reported in this study. The characteristic ofdegradation is described by tensile strength, melting point,and scanning electron micrographs as well as opticalmicrographs. The chemical composition of volatile oil ofLedum palustre is analyzed by gas chrography and massspectrometry. The mechanism of degradation and problemsneeded to be solved are also discussed.
