The flow field and aerodynamic performances for the scarfed lobed forced mixer are studied based on a computational fluid dynamics（CFD） technique. A series of computations are conducted to obtain the effects of the ...The flow field and aerodynamic performances for the scarfed lobed forced mixer are studied based on a computational fluid dynamics（CFD） technique. A series of computations are conducted to obtain the effects of the bypass ratio and the scarf angle on the mixing performance for the scarfed lobed mixer. Results show that the scarfed lobed mixer is reduced in the system weight. Meanwhile, aerodynamic performances are slightly improved compared with the normal lobed mixer. Two reasons for causing the mixing enhancement between the core and the bypass flow are as follows： （1） The stream-wise vortices shed from the training edge of the half/full scarfed lobed mixer earlier is enhanced by about 25%. （2） The mixing augmentation is also associated with the increase of the interface length caused by scarfing. The thermal mixing efficiency is enhanced with the increase of the bypass ratio and the scarfing angle. The scarfed lobed mixer design has no negative effects on the pressure loss. The total pressure recovery coefficient reaches above 0. 935 in various bypass ratios and scarfed angles. As the bypass ratio increases, the total pressure recovery coefficient also increases for the scarfed lobed mixer.展开更多
This study is focused on the kinetic characteristics of photocatalytic degradation of gaseous organic compounds on modified titanium dioxide/activated carbon composite photocatalyst(MTA).The MTA,which co-doping with i...This study is focused on the kinetic characteristics of photocatalytic degradation of gaseous organic compounds on modified titanium dioxide/activated carbon composite photocatalyst(MTA).The MTA,which co-doping with iron(Fe) and nitrogen(N),was synthesized by a sol-gel method,and its photocatalytic performance was investigated under different reaction conditions.The experimental data obtained were tested by the zero,first and second order kinetic model,and the factors affecting the kinetic model were analyzed.It was clearly demonstrated that the experimental data of toluene and acetone on MTA fit quite well with second order kinetic model equation,but the experimental data of formaldehyde fits well with zero order kinetic model equation.展开更多
The endogenous hydrogen sulfide （H2S）, as a new gasotransmitter, participates in many plant physio- logical processes. In this study, we found that both ethylene and drought strongly induced HaS synthetase AtD-CDes ...The endogenous hydrogen sulfide （H2S）, as a new gasotransmitter, participates in many plant physio- logical processes. In this study, we found that both ethylene and drought strongly induced HaS synthetase AtD-CDes gene expression and enzymatic activity. H2S synthesis inhibitors restrained the ethylene and drought induced stomatal closure in Arabidopsis. The H2S synthetase mutant Atd-cdes was insensitive to ethylene and drought, and overexpression of AtD-CDes conferred the transgenic plants more sensitive to ethylene and drought. Sequence analysis of AtD-CDes promoter showed that it contained ethylene response cis element ERE, and abiotic stress responsive cis elements MBS, LTR, and ABRE. The AtD- CDes promoter fused with GUS was transformed into Arabidopsis thaliana to get AtD-CDes promoter：：GUS transgenic plants. When treated with ethylene and drought stress, the enzymatic activity of fl-glucuronidase was higher in the leaves and stomata of transgenic Arabidopsis. Analyses of GUS activity from the transgenic plants har- boring different fragments of the promoter shows that the key section of AtD-CDes promoter response to ethylene was from the -697 to -408 bp, and the key section response to drought stress was from -90 to -1 bp. These results suggested that the H2S produced from AtD-CDesmay mediate ethylene and drought-induced stomatal movement.展开更多
基金Supported by the Civil Aviation Research Foundation of Nanjing University of Aeronautics and Astronautics~~
文摘The flow field and aerodynamic performances for the scarfed lobed forced mixer are studied based on a computational fluid dynamics（CFD） technique. A series of computations are conducted to obtain the effects of the bypass ratio and the scarf angle on the mixing performance for the scarfed lobed mixer. Results show that the scarfed lobed mixer is reduced in the system weight. Meanwhile, aerodynamic performances are slightly improved compared with the normal lobed mixer. Two reasons for causing the mixing enhancement between the core and the bypass flow are as follows： （1） The stream-wise vortices shed from the training edge of the half/full scarfed lobed mixer earlier is enhanced by about 25%. （2） The mixing augmentation is also associated with the increase of the interface length caused by scarfing. The thermal mixing efficiency is enhanced with the increase of the bypass ratio and the scarfing angle. The scarfed lobed mixer design has no negative effects on the pressure loss. The total pressure recovery coefficient reaches above 0. 935 in various bypass ratios and scarfed angles. As the bypass ratio increases, the total pressure recovery coefficient also increases for the scarfed lobed mixer.
基金Supported by the Natural Science Foundation of Guangdong Province,China(8151064101000049)
文摘This study is focused on the kinetic characteristics of photocatalytic degradation of gaseous organic compounds on modified titanium dioxide/activated carbon composite photocatalyst(MTA).The MTA,which co-doping with iron(Fe) and nitrogen(N),was synthesized by a sol-gel method,and its photocatalytic performance was investigated under different reaction conditions.The experimental data obtained were tested by the zero,first and second order kinetic model,and the factors affecting the kinetic model were analyzed.It was clearly demonstrated that the experimental data of toluene and acetone on MTA fit quite well with second order kinetic model equation,but the experimental data of formaldehyde fits well with zero order kinetic model equation.
基金supported by the National Natural Science Foundation of China (31170237, 31572107, 31401844, 31540090)
文摘The endogenous hydrogen sulfide （H2S）, as a new gasotransmitter, participates in many plant physio- logical processes. In this study, we found that both ethylene and drought strongly induced HaS synthetase AtD-CDes gene expression and enzymatic activity. H2S synthesis inhibitors restrained the ethylene and drought induced stomatal closure in Arabidopsis. The H2S synthetase mutant Atd-cdes was insensitive to ethylene and drought, and overexpression of AtD-CDes conferred the transgenic plants more sensitive to ethylene and drought. Sequence analysis of AtD-CDes promoter showed that it contained ethylene response cis element ERE, and abiotic stress responsive cis elements MBS, LTR, and ABRE. The AtD- CDes promoter fused with GUS was transformed into Arabidopsis thaliana to get AtD-CDes promoter：：GUS transgenic plants. When treated with ethylene and drought stress, the enzymatic activity of fl-glucuronidase was higher in the leaves and stomata of transgenic Arabidopsis. Analyses of GUS activity from the transgenic plants har- boring different fragments of the promoter shows that the key section of AtD-CDes promoter response to ethylene was from the -697 to -408 bp, and the key section response to drought stress was from -90 to -1 bp. These results suggested that the H2S produced from AtD-CDesmay mediate ethylene and drought-induced stomatal movement.
