To maintain the high-density plasma source in inductively coupled plasma(ICP),very high radiofrequency power is often delivered to the antenna,which can heat the dielectric windows near the antenna to high temperature...To maintain the high-density plasma source in inductively coupled plasma(ICP),very high radiofrequency power is often delivered to the antenna,which can heat the dielectric windows near the antenna to high temperature.This high temperature can modulate the plasma characteristics to a large degree.We thus study the effect of dielectric window temperature on plasma parameters in two different ICP structures based on COMSOL software.The distributions of various plasma species are examined at different dielectric window temperatures.The concentration of neutral gas is found to be largely modulated at high dielectric window temperature,which further affects the electron collision probability with neutrals and the electron temperature.However,the electron density profiles are barely affected by the dielectric window temperature,which is mainly concentrated at the center of the reactor due to the fixed power input and pressure.展开更多
The development of the cotton fiber is very sensitive to temperature variation, and high temperature stress often causes reduced fiber yield and fiber quality. Short-term high temperature stress often occurs during co...The development of the cotton fiber is very sensitive to temperature variation, and high temperature stress often causes reduced fiber yield and fiber quality. Short-term high temperature stress often occurs during cotton production, but little is known about the specific timing and duration of stress that affects fiber development. To make this clear, pot experiments were carried in 2014 and 2015 in a climate chamber using cotton cultivars HY370WR(less sensitive variety) and Sumian 15(heat sensitive variety), which present different temperature sensitivities. Changes of the most important fiber quality indices(i.e., fiber length, fiber strength and marcironaire) and three very important fiber development components(i.e., cellulose, sucrose and callose) were analyzed to define the time window and critical duration to the high temperature stress at 34°C(max38°C/min30°C). When developing bolls were subjected to 5 days of high temperature stress at different days post-anthesis(DPA), the changes(Δ%) of fiber length, strength and micronire, as a function of imposed time followed square polynomial eq. as y=a+bx+cx^2, and the time around 15 DPA was the most sensitive period for fiber quality development in response to heat stress. When 15 DPA bolls were heat-stressed for different durations(2, 3, 4, 5, 6, 7 days), the changes(Δ%) of fiber length, strength and micronire, as a function of stress duration followed logistic equations y=A_1-A_2/1+(x/x_0)~p+A_2. Referred to that 5, 10 and 15% are usually used as criteria to decide whether techniques are effective or changes are significant in crop culture practice and reguard to the fiber quality indices change range, we suggested that 5% changes of the major fiber quality indices(fiber length, fiber strength and micronaire) and 10% changes of fiber development components(cellulose, sucrose and callose) could be taken as criteria to judge whether fiber development and fiber quality have been significantly affected by high temperature stress. The key time window for cotton fiber development in response to the high temperature stress was 13–19 DPA, and the critical duration was about 5 days.展开更多
NH_(3)-SCR was one of the most promising de NO_x technologies and it has been widely applied in industrial NO_x reduction.However,with the further development of energy transformation in power generation sector,the de...NH_(3)-SCR was one of the most promising de NO_x technologies and it has been widely applied in industrial NO_x reduction.However,with the further development of energy transformation in power generation sector,the development of NH_(3)-SCR catalysts is facing some new challenges.It is becoming an urgent problem to solve low catalytic activity and stability of NH_(3)-SCR catalysts at the working condition of ultra-low temperature(≤200℃)and high concentrations of H_(2)O+SO_(2) due to the gradual deployment of new energy power plants.Furthermore,the traditional coal-fired power plants would need flexible operation with the increasing share of renewable energy generation.The NH_(3)-SCR catalysts which were applied in coal-fired power industry would be requested to work in a wide temperature window from 200℃ to 500℃ in the near future.Therefore,in this review,we summarized the progress of NH_(3)-SCR catalysts in solving these different industrial problems in recent years.And the research directions which were deserved to be focused on the development of NH_(3)-SCR catalysts for the energy transition of power generation sector are proposed.展开更多
基金financially supported by National Natural Science Foundation of China(NSFC)(Nos.12105035 and 11935005)Guangdong Basic and Applied Basic Research Foundation(No.2021B1515120018)+1 种基金the Fundamental Research Funds for the Central Universities(No.DUT21TD104)the Advanced Space Propulsion Laboratory of BICE and Beijing Engineering Research Center of Efficient and Green Aerospace Propulsion Technology(No.Lab ASP-2020-01)。
文摘To maintain the high-density plasma source in inductively coupled plasma(ICP),very high radiofrequency power is often delivered to the antenna,which can heat the dielectric windows near the antenna to high temperature.This high temperature can modulate the plasma characteristics to a large degree.We thus study the effect of dielectric window temperature on plasma parameters in two different ICP structures based on COMSOL software.The distributions of various plasma species are examined at different dielectric window temperatures.The concentration of neutral gas is found to be largely modulated at high dielectric window temperature,which further affects the electron collision probability with neutrals and the electron temperature.However,the electron density profiles are barely affected by the dielectric window temperature,which is mainly concentrated at the center of the reactor due to the fixed power input and pressure.
基金funded by the National Natural Science Foundation of China(31271654,31471444)the Natural Science Foundation of Jiangsu Province,China(BK20131318)
文摘The development of the cotton fiber is very sensitive to temperature variation, and high temperature stress often causes reduced fiber yield and fiber quality. Short-term high temperature stress often occurs during cotton production, but little is known about the specific timing and duration of stress that affects fiber development. To make this clear, pot experiments were carried in 2014 and 2015 in a climate chamber using cotton cultivars HY370WR(less sensitive variety) and Sumian 15(heat sensitive variety), which present different temperature sensitivities. Changes of the most important fiber quality indices(i.e., fiber length, fiber strength and marcironaire) and three very important fiber development components(i.e., cellulose, sucrose and callose) were analyzed to define the time window and critical duration to the high temperature stress at 34°C(max38°C/min30°C). When developing bolls were subjected to 5 days of high temperature stress at different days post-anthesis(DPA), the changes(Δ%) of fiber length, strength and micronire, as a function of imposed time followed square polynomial eq. as y=a+bx+cx^2, and the time around 15 DPA was the most sensitive period for fiber quality development in response to heat stress. When 15 DPA bolls were heat-stressed for different durations(2, 3, 4, 5, 6, 7 days), the changes(Δ%) of fiber length, strength and micronire, as a function of stress duration followed logistic equations y=A_1-A_2/1+(x/x_0)~p+A_2. Referred to that 5, 10 and 15% are usually used as criteria to decide whether techniques are effective or changes are significant in crop culture practice and reguard to the fiber quality indices change range, we suggested that 5% changes of the major fiber quality indices(fiber length, fiber strength and micronaire) and 10% changes of fiber development components(cellulose, sucrose and callose) could be taken as criteria to judge whether fiber development and fiber quality have been significantly affected by high temperature stress. The key time window for cotton fiber development in response to the high temperature stress was 13–19 DPA, and the critical duration was about 5 days.
基金financially supported by the National Natural Science Foundation of China(No.52072306)the National Key R&D Program of China(No.2021YFB3701500)the Fundamental Research Funds for the Central Universities(Nos.3102019PJ008 and 3102018JCC002)。
文摘NH_(3)-SCR was one of the most promising de NO_x technologies and it has been widely applied in industrial NO_x reduction.However,with the further development of energy transformation in power generation sector,the development of NH_(3)-SCR catalysts is facing some new challenges.It is becoming an urgent problem to solve low catalytic activity and stability of NH_(3)-SCR catalysts at the working condition of ultra-low temperature(≤200℃)and high concentrations of H_(2)O+SO_(2) due to the gradual deployment of new energy power plants.Furthermore,the traditional coal-fired power plants would need flexible operation with the increasing share of renewable energy generation.The NH_(3)-SCR catalysts which were applied in coal-fired power industry would be requested to work in a wide temperature window from 200℃ to 500℃ in the near future.Therefore,in this review,we summarized the progress of NH_(3)-SCR catalysts in solving these different industrial problems in recent years.And the research directions which were deserved to be focused on the development of NH_(3)-SCR catalysts for the energy transition of power generation sector are proposed.