Plasma processes are among the emerging technologies for volatile organic compounds (VOCs) abatement[1]. Both thermal plasmas and non-equilibrium plasmas (cold plasmas) are being developed for VOCs cleanup[2,3]. Parti...Plasma processes are among the emerging technologies for volatile organic compounds (VOCs) abatement[1]. Both thermal plasmas and non-equilibrium plasmas (cold plasmas) are being developed for VOCs cleanup[2,3]. Particularly, pulsed corona discharges offer several advantages over conventional VOCs abatement techniques[4-7]. To optimize the existing technology and to develop it further, there is need to understand the mechanisms involved in plasma chemical reactions. Furthermore, it is strongly desirable to be able to predict the behavior of new VOCs in non-equilibrium plasma environment from the data known for a few representative compounds. Pulsed corona discharge technique is introduced here with citation of relevant literature. Fundamental principles, useful for predicting the VOCs' decomposition behavior, have been worked out from the published literature. Latest developments in the area, targeted to minimize the energy losses, improve the VOCs destruction efficiency and reduce the generation of unwanted organic and inorganic by-products, are presented.展开更多
The surface feature of contaminative oil is analysed and the theory of carrier purification technology for hydraulic oil is put forward. Experiments have been done in laboratory. The main performance of the purified o...The surface feature of contaminative oil is analysed and the theory of carrier purification technology for hydraulic oil is put forward. Experiments have been done in laboratory. The main performance of the purified oil has got to a level of new oil.展开更多
In this paper, a coupled model was used to estimate the responses of soil moisture and net primary production of vegetation(NPP) to increasing atmospheric CO2 concentration and climate change. The analysis uses three ...In this paper, a coupled model was used to estimate the responses of soil moisture and net primary production of vegetation(NPP) to increasing atmospheric CO2 concentration and climate change. The analysis uses three experiments simulated by the second-generation Earth System Model(CanESM2) of the Canadian Centre for Climate Modelling and Analysis(CCCma), which are part of the phase 5 of the Coupled Model Intercomparison Project(CMIP5). The authors focus on the magnitude and evolution of responses in soil moisture and NPP using simulations modeled by CanESM, in which the individual effects of increasing CO2 concentration and climate change and their combined effect are separately accounted for. When considering only the single effect of climate change, the soil moisture and NPP have a linear trend of 0.03 kg m–2 yr–1 and –0.14 gC m–2 yr–2, respectively. However, such a reduction in the global NPP results from the decrease of NPP at lower latitudes and in the Southern Hemisphere, although increased NPP has been shown in high northern latitudes. The largest negative trend is located in the Amazon basin at –1.79 gC m–2 yr–2. For the individual effect of increasing CO2 concentration, both soil moisture and NPP show increases, with an elevated linear trend of 0.02 kg m–2 yr–1 and 0.84 gC m–2 yr–2, respectively. Most regions show an increasing NPP, except Alaska. For the combined effect of increasing atmospheric CO2 and climate change, the increased soil moisture and NPP exhibit a linear trend of 0.04 kg m–2 yr–1 and 0.83 gC m–2 yr–2 at a global scale. In the Amazon basin, the higher reduction in soil moisture is illustrated by the model, with a linear trend of –0.39 kg m–2 yr–1, for the combined effect. Such a change in soil moisture is caused by a weakened Walker circulation simulated by this coupled model, compared with the single effect of increasing CO2 concentration(experiment M2), and a consequence of the reduction in NPP is also shown in this area, with a linear trend of-0.16 gC m-2 yr-2.展开更多
Graphene is a one-atom-thick sheet of graphite comprising sp2-hybridized carbon atoms arranged in the hexagonal honeycomb lattices. By removing the honeycomb lattices and forming nanopores with specific geometry and s...Graphene is a one-atom-thick sheet of graphite comprising sp2-hybridized carbon atoms arranged in the hexagonal honeycomb lattices. By removing the honeycomb lattices and forming nanopores with specific geometry and size, nanoporous graphene has been demonstrated as a very high-efficiency separation membrane, due to the ultrafast molecular permeation rate for its one-atom thickness. This review focuses on the recent advances in nanoporous graphene membrane for the applications of gas separation and water purification, with a major emphasis on the molecular permeation mechanisms and the advanced fabrication methods of this state-of-the-art membrane. We highlight the advanced theoretical and experimental works and discuss the gas/water molecular transport mechanisms through the graphene nanopores accompanied with theoretical models. In addition, we summarize some representative membrane fabrication methods, covering the graphene transfer to porous substrates and the pore generation. We anticipate that this review can provide a platform for understanding the current challenges to make the conceptual membrane a reality and attracting more and more attentions from scientists and engineers.展开更多
文摘Plasma processes are among the emerging technologies for volatile organic compounds (VOCs) abatement[1]. Both thermal plasmas and non-equilibrium plasmas (cold plasmas) are being developed for VOCs cleanup[2,3]. Particularly, pulsed corona discharges offer several advantages over conventional VOCs abatement techniques[4-7]. To optimize the existing technology and to develop it further, there is need to understand the mechanisms involved in plasma chemical reactions. Furthermore, it is strongly desirable to be able to predict the behavior of new VOCs in non-equilibrium plasma environment from the data known for a few representative compounds. Pulsed corona discharge technique is introduced here with citation of relevant literature. Fundamental principles, useful for predicting the VOCs' decomposition behavior, have been worked out from the published literature. Latest developments in the area, targeted to minimize the energy losses, improve the VOCs destruction efficiency and reduce the generation of unwanted organic and inorganic by-products, are presented.
文摘The surface feature of contaminative oil is analysed and the theory of carrier purification technology for hydraulic oil is put forward. Experiments have been done in laboratory. The main performance of the purified oil has got to a level of new oil.
基金supported by the project of the National Natural Science Foundation of China (Grant Nos. 41275082 and 41305070)the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA05110103)the Knowledge Innovation Program of the Chinese Academy of Sciences (Grant Nos. KZCX2-EW-QN208 and 7-122158)
文摘In this paper, a coupled model was used to estimate the responses of soil moisture and net primary production of vegetation(NPP) to increasing atmospheric CO2 concentration and climate change. The analysis uses three experiments simulated by the second-generation Earth System Model(CanESM2) of the Canadian Centre for Climate Modelling and Analysis(CCCma), which are part of the phase 5 of the Coupled Model Intercomparison Project(CMIP5). The authors focus on the magnitude and evolution of responses in soil moisture and NPP using simulations modeled by CanESM, in which the individual effects of increasing CO2 concentration and climate change and their combined effect are separately accounted for. When considering only the single effect of climate change, the soil moisture and NPP have a linear trend of 0.03 kg m–2 yr–1 and –0.14 gC m–2 yr–2, respectively. However, such a reduction in the global NPP results from the decrease of NPP at lower latitudes and in the Southern Hemisphere, although increased NPP has been shown in high northern latitudes. The largest negative trend is located in the Amazon basin at –1.79 gC m–2 yr–2. For the individual effect of increasing CO2 concentration, both soil moisture and NPP show increases, with an elevated linear trend of 0.02 kg m–2 yr–1 and 0.84 gC m–2 yr–2, respectively. Most regions show an increasing NPP, except Alaska. For the combined effect of increasing atmospheric CO2 and climate change, the increased soil moisture and NPP exhibit a linear trend of 0.04 kg m–2 yr–1 and 0.83 gC m–2 yr–2 at a global scale. In the Amazon basin, the higher reduction in soil moisture is illustrated by the model, with a linear trend of –0.39 kg m–2 yr–1, for the combined effect. Such a change in soil moisture is caused by a weakened Walker circulation simulated by this coupled model, compared with the single effect of increasing CO2 concentration(experiment M2), and a consequence of the reduction in NPP is also shown in this area, with a linear trend of-0.16 gC m-2 yr-2.
基金supported by the National Natural Science Foundation of China(51425603 and 51236007)
文摘Graphene is a one-atom-thick sheet of graphite comprising sp2-hybridized carbon atoms arranged in the hexagonal honeycomb lattices. By removing the honeycomb lattices and forming nanopores with specific geometry and size, nanoporous graphene has been demonstrated as a very high-efficiency separation membrane, due to the ultrafast molecular permeation rate for its one-atom thickness. This review focuses on the recent advances in nanoporous graphene membrane for the applications of gas separation and water purification, with a major emphasis on the molecular permeation mechanisms and the advanced fabrication methods of this state-of-the-art membrane. We highlight the advanced theoretical and experimental works and discuss the gas/water molecular transport mechanisms through the graphene nanopores accompanied with theoretical models. In addition, we summarize some representative membrane fabrication methods, covering the graphene transfer to porous substrates and the pore generation. We anticipate that this review can provide a platform for understanding the current challenges to make the conceptual membrane a reality and attracting more and more attentions from scientists and engineers.
