Monte Carlo simulations are adopted to study the electron motion in the mixture of H2 and CH4 during diamond synthesis via Glow Plasma-assisted Chemical Vapor Deposition (GPCVD). The non-uniform electric field is used...Monte Carlo simulations are adopted to study the electron motion in the mixture of H2 and CH4 during diamond synthesis via Glow Plasma-assisted Chemical Vapor Deposition (GPCVD). The non-uniform electric field is used and the avalanche of electrons is taken into account in this simulation. The average energy distribution of electrons and the space distribution of effective species such as CH3, CH+3, CH+ and H at various gas pressures are given in this paper, and optimum experimental conditions are inferred from these results.展开更多
Manure management strategies should reflect current animal feeding practices and encourage recycling of organic waste to help protect our environment. This research investigated greenhouse gas （GHG） emissions during...Manure management strategies should reflect current animal feeding practices and encourage recycling of organic waste to help protect our environment. This research investigated greenhouse gas （GHG） emissions during cattle manure stockpiling or composting with and without construction and demolition （C＆D） waste. Manure was collected from cattle fed a typical finishing diet （CK manure） and from cattle on diets which included 30% dried distillers grains with solubles （DG manure）. The CK and DG manures were co-composted with （4：1） C＆D waste （treatments： CK CD, DG CD）, composted alone （treatments： CK and DG） in 13 m3 bins or stockpiled without C＆D ~vaste （treatments： CK ST and DGST） for 99 days. Manure type （CK vs. DG manure） had no effect on GHG emissions-over the 99 day manure composting or stockpiling. Composting with C＆D waste 2 produced similar CO2 emissions, about double that from manure stockpthng （7.9 kgC.m^-2）. In contrast, CH4 emissions were reduced by the inclusion of C＆D waste （64 gC.m^-1 with C＆D vs. 244 gC.m 2 without C＆D） while the manure stockpile emitted the greatest amount of CH4 （464 gC. m 2）. Additionally, only 0.48% of C was emitted in CH4 form with C＆D waste, compared to 1.68% when composting without C＆D waste and 7.00% when cattle manure was stockpiled. The N2O emissions （12.4 to 18.0 gN.m ） were similar across all treatments. The lower CH4 emissions with C＆D waste are beneficial in reducing overall GHG emissions from manure composting, while reducing the amount of material entering landfills.展开更多
基金This work was supported by Doctor Foundation of Hebei Education Committee Hebei Natural Science Foundation(599091 ) of China
文摘Monte Carlo simulations are adopted to study the electron motion in the mixture of H2 and CH4 during diamond synthesis via Glow Plasma-assisted Chemical Vapor Deposition (GPCVD). The non-uniform electric field is used and the avalanche of electrons is taken into account in this simulation. The average energy distribution of electrons and the space distribution of effective species such as CH3, CH+3, CH+ and H at various gas pressures are given in this paper, and optimum experimental conditions are inferred from these results.
文摘Manure management strategies should reflect current animal feeding practices and encourage recycling of organic waste to help protect our environment. This research investigated greenhouse gas （GHG） emissions during cattle manure stockpiling or composting with and without construction and demolition （C＆D） waste. Manure was collected from cattle fed a typical finishing diet （CK manure） and from cattle on diets which included 30% dried distillers grains with solubles （DG manure）. The CK and DG manures were co-composted with （4：1） C＆D waste （treatments： CK CD, DG CD）, composted alone （treatments： CK and DG） in 13 m3 bins or stockpiled without C＆D ~vaste （treatments： CK ST and DGST） for 99 days. Manure type （CK vs. DG manure） had no effect on GHG emissions-over the 99 day manure composting or stockpiling. Composting with C＆D waste 2 produced similar CO2 emissions, about double that from manure stockpthng （7.9 kgC.m^-2）. In contrast, CH4 emissions were reduced by the inclusion of C＆D waste （64 gC.m^-1 with C＆D vs. 244 gC.m 2 without C＆D） while the manure stockpile emitted the greatest amount of CH4 （464 gC. m 2）. Additionally, only 0.48% of C was emitted in CH4 form with C＆D waste, compared to 1.68% when composting without C＆D waste and 7.00% when cattle manure was stockpiled. The N2O emissions （12.4 to 18.0 gN.m ） were similar across all treatments. The lower CH4 emissions with C＆D waste are beneficial in reducing overall GHG emissions from manure composting, while reducing the amount of material entering landfills.
