Modifiers have a broad array of influences on extraction with liquids in standard state, supercritical fluid extraction (SFE), trapping by SFE and supercritical fluid chromatography (SFC). They can significantly chang...Modifiers have a broad array of influences on extraction with liquids in standard state, supercritical fluid extraction (SFE), trapping by SFE and supercritical fluid chromatography (SFC). They can significantly change the qualitative and quantitative results. Quantitative and qualitative results can be influenced by different extractants and modifiers in different ways as it was shown by Brondz et al. at 2007 in “The real nature of the indole alkaloids in Cortinarius infractus: Evaluation of artifact formation through solvent extraction method development”, J. Chromatography A, 1148, 1-7. The choice of correct extractant, modifier, and trapper to the bulk mobile phase for supercritical fluids (SFs) or for liquids in subcritical or in the liquids in standard state is a challenge in any extraction procedure. This is the second paper in a sequence that describes the influence of extractants and modifiers on the performance of SFs and results of extraction with liquids in standard state and SFE. Here, attention is given to possible mistakes in qualitative and quantitative results by poor understanding of the influence of extractants, modifiers, and trappers on extraction and trapping process by a careless choice of extractant, modifier, and trapper for extraction with liquids in standard state and SFE. The SF chosen for discussion in the paper is CO2. However, similar effects can be observed with use of other SFs and fluids in subcritical and standard states. In this paper, the discussion of lipids, fatty and carboxylic acids have been chosen as target analytes for extraction, trapping and analysis. Some examples from extraction with liquids in the standard state and trapping in the supercritical state (collection) have been furnished with the wrong extractant, modifier, or trapper which is presented for illustration of inappropriate choice of extractants, modifiers, and trappers.展开更多
[ Objective ] To figure out the optimal setting height of gyplure trappers for controlling such pests as Spodoptera litura, Helicoverpa assuha, Helicoverpa armigera Hubner and Agrotis ypsilon that endanger tobacco lea...[ Objective ] To figure out the optimal setting height of gyplure trappers for controlling such pests as Spodoptera litura, Helicoverpa assuha, Helicoverpa armigera Hubner and Agrotis ypsilon that endanger tobacco leaves, and screen trappers suitable for the tobacco production. [ Method] In the growth season of to- bacco plants, moth trapper, new moth trapper lure/insect inlet are set up at four different heights (70, 110, 150 and 190 cm vertically from soil surface in the field), to investigate the quantity of trapped moths. [ Result ] For both trappers, the height of trapping the most moths is 70 - 150 cm, so the initial height of lure/ insect inlet should be 120 cm, considering the 1-m mature tobacco plant height and the 20-cm distance between lure/insect inlet and crop canopy. [ Conclusion] Mother trapper is cheaper, and the new moth trapper is convenient and requires less management cost. The former is favorable for trapping S. litura, and the latter for H. assulta, H. armigera Hubner, and both of them are suitable for trapping A. ypsilon. In tobacco producing regions of Yunnan, population bases of the four noctuids endangering tobacco leaves show the sequence of S. litura 〉 A. ypsilon 〉 H. armigera Hubner 〉 H. assuha. But in tobacco production, H. armigera Hubner, H. assuha, and A. ypsilon cause the most serious damages, so the four noctuids must be controlled. Key words Tobacco noctuid; Sex lure; Trapper; Setting height展开更多
Bi/semiconductor photocatalysts have extensively been applied in the production of hydrogen,CO_(2) reduction and environmental remediation in recent years.This short review summarizes the role of Bi metal as a plasma ...Bi/semiconductor photocatalysts have extensively been applied in the production of hydrogen,CO_(2) reduction and environmental remediation in recent years.This short review summarizes the role of Bi metal as a plasma photocatalyst and cocatalyst.As a cocatalyst,Bi metal can be electron/hole trappers,charge transfer mediators,or oxygen vacancy coordinators.In addition,the preparation methods of the Bi/semiconductor photocatalysts are also reviewed.Challenges and future research directions related to Bi/semiconductor photocatalysts are discussed and summarized,including the use of advanced characterization techniques to refine the reaction mechanism,the difficulties of preparing Bi single atom catalyst,and the improvement of the reduction ability of Bi-based photocatalysts.This review helps understand the reaction mechanisms of the composite photocatalytic systems containing Bi metal and proposes new perspectives for designing the photocatalysts which can control air pollution via a reductive process.展开更多
The interfacial electrification properties play an important role in the electrochemical corrosion reaction which leads the electrostatic charge to generate and accumulate on the metal surface when the insulating oil ...The interfacial electrification properties play an important role in the electrochemical corrosion reaction which leads the electrostatic charge to generate and accumulate on the metal surface when the insulating oil flows through a metal pipe. In this paper, the interfacial electrification properties resulted by the oil flow rate and the action of electric charge trapper are investigated by measuring the current and potential on the surface of the test metal pipe. The measured results showed that the current and potential between the metal pipe and the earth increased with the rise of flow rate; and as the flow rate increased, the growth trends of the current and potential difference between two close flow rates increased and decreased, respectively, while there was an electric charge trapper set in the radial direction of the pipe, the measured current and potential decreased compared with that of without electric charge trapper, which was because it captured and caught part of charge in the oil flow bulk to neutralize the opposite charge on the surface of the metal pipe.展开更多
文摘Modifiers have a broad array of influences on extraction with liquids in standard state, supercritical fluid extraction (SFE), trapping by SFE and supercritical fluid chromatography (SFC). They can significantly change the qualitative and quantitative results. Quantitative and qualitative results can be influenced by different extractants and modifiers in different ways as it was shown by Brondz et al. at 2007 in “The real nature of the indole alkaloids in Cortinarius infractus: Evaluation of artifact formation through solvent extraction method development”, J. Chromatography A, 1148, 1-7. The choice of correct extractant, modifier, and trapper to the bulk mobile phase for supercritical fluids (SFs) or for liquids in subcritical or in the liquids in standard state is a challenge in any extraction procedure. This is the second paper in a sequence that describes the influence of extractants and modifiers on the performance of SFs and results of extraction with liquids in standard state and SFE. Here, attention is given to possible mistakes in qualitative and quantitative results by poor understanding of the influence of extractants, modifiers, and trappers on extraction and trapping process by a careless choice of extractant, modifier, and trapper for extraction with liquids in standard state and SFE. The SF chosen for discussion in the paper is CO2. However, similar effects can be observed with use of other SFs and fluids in subcritical and standard states. In this paper, the discussion of lipids, fatty and carboxylic acids have been chosen as target analytes for extraction, trapping and analysis. Some examples from extraction with liquids in the standard state and trapping in the supercritical state (collection) have been furnished with the wrong extractant, modifier, or trapper which is presented for illustration of inappropriate choice of extractants, modifiers, and trappers.
基金Sponsored by Yunnan Provincial Tobacco Monopoly Administration(Company)Scientific and Technological Program(2012YN04,2010YN09)State Tobacco Monopoly Bureau(110200902065)
文摘[ Objective ] To figure out the optimal setting height of gyplure trappers for controlling such pests as Spodoptera litura, Helicoverpa assuha, Helicoverpa armigera Hubner and Agrotis ypsilon that endanger tobacco leaves, and screen trappers suitable for the tobacco production. [ Method] In the growth season of to- bacco plants, moth trapper, new moth trapper lure/insect inlet are set up at four different heights (70, 110, 150 and 190 cm vertically from soil surface in the field), to investigate the quantity of trapped moths. [ Result ] For both trappers, the height of trapping the most moths is 70 - 150 cm, so the initial height of lure/ insect inlet should be 120 cm, considering the 1-m mature tobacco plant height and the 20-cm distance between lure/insect inlet and crop canopy. [ Conclusion] Mother trapper is cheaper, and the new moth trapper is convenient and requires less management cost. The former is favorable for trapping S. litura, and the latter for H. assulta, H. armigera Hubner, and both of them are suitable for trapping A. ypsilon. In tobacco producing regions of Yunnan, population bases of the four noctuids endangering tobacco leaves show the sequence of S. litura 〉 A. ypsilon 〉 H. armigera Hubner 〉 H. assuha. But in tobacco production, H. armigera Hubner, H. assuha, and A. ypsilon cause the most serious damages, so the four noctuids must be controlled. Key words Tobacco noctuid; Sex lure; Trapper; Setting height
基金by“Key Laboratory of Aero sol Chemistry and Physics,Institute of Earth Environment,CAS(No.KLACP1701)”“State Key Laboratory of Loess and Quaternary Geology,Institute of Earth Environment,CAS(No.SKLLQG1516)”。
文摘Bi/semiconductor photocatalysts have extensively been applied in the production of hydrogen,CO_(2) reduction and environmental remediation in recent years.This short review summarizes the role of Bi metal as a plasma photocatalyst and cocatalyst.As a cocatalyst,Bi metal can be electron/hole trappers,charge transfer mediators,or oxygen vacancy coordinators.In addition,the preparation methods of the Bi/semiconductor photocatalysts are also reviewed.Challenges and future research directions related to Bi/semiconductor photocatalysts are discussed and summarized,including the use of advanced characterization techniques to refine the reaction mechanism,the difficulties of preparing Bi single atom catalyst,and the improvement of the reduction ability of Bi-based photocatalysts.This review helps understand the reaction mechanisms of the composite photocatalytic systems containing Bi metal and proposes new perspectives for designing the photocatalysts which can control air pollution via a reductive process.
文摘The interfacial electrification properties play an important role in the electrochemical corrosion reaction which leads the electrostatic charge to generate and accumulate on the metal surface when the insulating oil flows through a metal pipe. In this paper, the interfacial electrification properties resulted by the oil flow rate and the action of electric charge trapper are investigated by measuring the current and potential on the surface of the test metal pipe. The measured results showed that the current and potential between the metal pipe and the earth increased with the rise of flow rate; and as the flow rate increased, the growth trends of the current and potential difference between two close flow rates increased and decreased, respectively, while there was an electric charge trapper set in the radial direction of the pipe, the measured current and potential decreased compared with that of without electric charge trapper, which was because it captured and caught part of charge in the oil flow bulk to neutralize the opposite charge on the surface of the metal pipe.