NH_(3)作为氢能载体,可实现氢能远距离输运。针对NH_(3)燃烧的反应性低、稳定性差、高燃料型NO_(x)排放问题,设计旋流燃烧器和空气分级燃烧室,实验研究功率为5~23 k W的NH_(3)、NH_(3)/CH_(4)扩散火焰NO_(x)排放特性。并采用化学反应器...NH_(3)作为氢能载体,可实现氢能远距离输运。针对NH_(3)燃烧的反应性低、稳定性差、高燃料型NO_(x)排放问题,设计旋流燃烧器和空气分级燃烧室,实验研究功率为5~23 k W的NH_(3)、NH_(3)/CH_(4)扩散火焰NO_(x)排放特性。并采用化学反应器网络(CRN)进行化学动力学模拟,分析排放变化的原因。结果表明:5 kW、Ф_(pri)=1.05的条件下,NH_(3)火焰NO_(x)测量排放最低为114.4×10^(-6)@15%O_(2);随着功率升高,NO_(x)排放增加,且导致燃烧不充分、火焰延长,此时最佳Ф_(pri)提前、燃烧范围减少、NO_(x)进一步增加;本文的CRN更适合模拟预混燃烧的NO_(x)排放,而不是扩散燃烧;功率升高不会改变反应路径,但生成NO的基元反应速率的升高幅度略大于消耗NO的基元反应速率,从而导致NO排放升高.展开更多
The methylammonium lead triiodide(CH_(3)NH_(3)PbI_(3))-based perovskite shows a great alluring prospect in areas of solar cells, lasers, photodetectors, and light emitting diodes owing to their excellent optical and e...The methylammonium lead triiodide(CH_(3)NH_(3)PbI_(3))-based perovskite shows a great alluring prospect in areas of solar cells, lasers, photodetectors, and light emitting diodes owing to their excellent optical and electrical advantages. However,it is very sensitive to the surrounding oxygen and moisture, which limits its development seriously. It is urgent to spare no effort to enhance its optical and electrical stability for further application. In this paper, we synthesize the MAPbI_(3) perovskite film on the glass substrate with/without the ionic liquid(IL) of 1-Butyl-3-methylimidazolium tetrafluoroborate(BMIMBF_(4)) by a simple two-step sequential solution method. The additive of BMIMBF_(4)can improve the quality of crystal structure. Moreover, the photo-luminescence(PL) intensity of MAPbI_(3) film with BMIMBF_(4) is much stronger than the pure MAPbI_(3) film after a week in the air, which is almost ten-fold of the pure one. Meanwhile, under the illumination of 405-nm continuous wave(CW) laser, the fluorescent duration of the MAPbI_(3) film with BMIMBF_(4) is approximately 2.75 min, while the pure MAPbI;film is only about 6 s. In fact, ionic liquid of BMIMBF_(4) in the perovskite film plays a role of passivation, which prevents the dissolution of MAPbI_(3) into CH_(3)NH_(3)and PbI_(2) and thus enhances the stability of environment. In addition, the ionic liquid of BMIMBF;possesses high ionic conductivity, which accelerates the electron transport, so it is beneficial for the perovskite film in the areas of solar cells, photodetectors, and lasers. This interesting experiment provides a promising way to develop the perovskite’s further application.展开更多
【目的】研究不同温度条件下的石油烃降解产甲烷菌系中是否存在乙酸互营氧化产甲烷代谢途径。【方法】以3个不同温度条件的正十六烷烃降解产甲烷菌系Y15(15℃)、M82(35℃)和SK(55℃)作为接种物,通过乙酸喂养实验、并添加乙酸营养型产甲...【目的】研究不同温度条件下的石油烃降解产甲烷菌系中是否存在乙酸互营氧化产甲烷代谢途径。【方法】以3个不同温度条件的正十六烷烃降解产甲烷菌系Y15(15℃)、M82(35℃)和SK(55℃)作为接种物,通过乙酸喂养实验、并添加乙酸营养型产甲烷古菌的选择性抑制剂NH4Cl和CH3F,结合末端限制性片段长度多态性(terminal restriction fragment length polymorphism,T-RFLP)和克隆文库技术,分析乙酸产甲烷潜力及产甲烷古菌群落的演替趋势,推测产甲烷代谢途径的变化趋势。【结果】无论是否添加NH4Cl和CH3F,这3个菌系都可以利用乙酸生长并产生甲烷,但是添加NH4Cl和CH3F后产甲烷延滞期增加,最大比甲烷增长速率降低;只添加乙酸后,3个不同温度的菌系的古菌群落主要由乙酸营养型产甲烷古菌甲烷鬃毛菌属(Methanosaeta)组成,其丰度分别为92.8±1.4%、97.3±2.4%和82.8±9.0%;当添加选择性抑制剂NH4Cl,3个菌系中的Methanosaeta的丰度分别变为98.5±0.7%、87.4±4.8%和6.1±8.6%,中温菌系M82中氢营养型产甲烷古菌甲烷袋装菌属(Methanoculleus)的相对丰度增加到12.6±4.0%,高温菌系SK中另一类氢营养型产甲烷古菌甲烷热杆菌属(Methanothermobacter)增至84.3±1.5%;当添加选择性抑制剂CH3F,Methanosaeta丰度分别降至77.1±14.5%,86.4±6.1%和35.8±7.8%,低温菌系Y15中的甲烷八叠球菌属(Methanosarcina)增高(15.7±21%),这类产甲烷古菌具有多种产甲烷代谢途径,M82中Methanoculleus丰度上升到13.6±13.1%,SK中Methanothermobacter丰度增大到48.5±11.2%。【结论】在低温条件下,菌系Y15可能主要通过乙酸裂解完成产甲烷代谢,在中高温条件下,菌系M82和SK中可能存在乙酸互营氧化产甲烷代谢途径,并且甲烷的产生分别通过不同种群的氢营养型产甲烷古菌来完成。展开更多
文摘NH_(3)作为氢能载体,可实现氢能远距离输运。针对NH_(3)燃烧的反应性低、稳定性差、高燃料型NO_(x)排放问题,设计旋流燃烧器和空气分级燃烧室,实验研究功率为5~23 k W的NH_(3)、NH_(3)/CH_(4)扩散火焰NO_(x)排放特性。并采用化学反应器网络(CRN)进行化学动力学模拟,分析排放变化的原因。结果表明:5 kW、Ф_(pri)=1.05的条件下,NH_(3)火焰NO_(x)测量排放最低为114.4×10^(-6)@15%O_(2);随着功率升高,NO_(x)排放增加,且导致燃烧不充分、火焰延长,此时最佳Ф_(pri)提前、燃烧范围减少、NO_(x)进一步增加;本文的CRN更适合模拟预混燃烧的NO_(x)排放,而不是扩散燃烧;功率升高不会改变反应路径,但生成NO的基元反应速率的升高幅度略大于消耗NO的基元反应速率,从而导致NO排放升高.
基金Project supported by the National Key Research and Development Program of China (Grant No. 2018YFC2001100)the Natural National Science Foundation of China (Grant No. 61574017)+1 种基金the Fundamental Research Funds for Central Universities, China (Grant No. 2017CX10007)the Open Foundation of Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured Materials, Guangxi University (Grant No. 2020GXYSOF08)。
文摘The methylammonium lead triiodide(CH_(3)NH_(3)PbI_(3))-based perovskite shows a great alluring prospect in areas of solar cells, lasers, photodetectors, and light emitting diodes owing to their excellent optical and electrical advantages. However,it is very sensitive to the surrounding oxygen and moisture, which limits its development seriously. It is urgent to spare no effort to enhance its optical and electrical stability for further application. In this paper, we synthesize the MAPbI_(3) perovskite film on the glass substrate with/without the ionic liquid(IL) of 1-Butyl-3-methylimidazolium tetrafluoroborate(BMIMBF_(4)) by a simple two-step sequential solution method. The additive of BMIMBF_(4)can improve the quality of crystal structure. Moreover, the photo-luminescence(PL) intensity of MAPbI_(3) film with BMIMBF_(4) is much stronger than the pure MAPbI_(3) film after a week in the air, which is almost ten-fold of the pure one. Meanwhile, under the illumination of 405-nm continuous wave(CW) laser, the fluorescent duration of the MAPbI_(3) film with BMIMBF_(4) is approximately 2.75 min, while the pure MAPbI;film is only about 6 s. In fact, ionic liquid of BMIMBF_(4) in the perovskite film plays a role of passivation, which prevents the dissolution of MAPbI_(3) into CH_(3)NH_(3)and PbI_(2) and thus enhances the stability of environment. In addition, the ionic liquid of BMIMBF;possesses high ionic conductivity, which accelerates the electron transport, so it is beneficial for the perovskite film in the areas of solar cells, photodetectors, and lasers. This interesting experiment provides a promising way to develop the perovskite’s further application.
文摘【目的】研究不同温度条件下的石油烃降解产甲烷菌系中是否存在乙酸互营氧化产甲烷代谢途径。【方法】以3个不同温度条件的正十六烷烃降解产甲烷菌系Y15(15℃)、M82(35℃)和SK(55℃)作为接种物,通过乙酸喂养实验、并添加乙酸营养型产甲烷古菌的选择性抑制剂NH4Cl和CH3F,结合末端限制性片段长度多态性(terminal restriction fragment length polymorphism,T-RFLP)和克隆文库技术,分析乙酸产甲烷潜力及产甲烷古菌群落的演替趋势,推测产甲烷代谢途径的变化趋势。【结果】无论是否添加NH4Cl和CH3F,这3个菌系都可以利用乙酸生长并产生甲烷,但是添加NH4Cl和CH3F后产甲烷延滞期增加,最大比甲烷增长速率降低;只添加乙酸后,3个不同温度的菌系的古菌群落主要由乙酸营养型产甲烷古菌甲烷鬃毛菌属(Methanosaeta)组成,其丰度分别为92.8±1.4%、97.3±2.4%和82.8±9.0%;当添加选择性抑制剂NH4Cl,3个菌系中的Methanosaeta的丰度分别变为98.5±0.7%、87.4±4.8%和6.1±8.6%,中温菌系M82中氢营养型产甲烷古菌甲烷袋装菌属(Methanoculleus)的相对丰度增加到12.6±4.0%,高温菌系SK中另一类氢营养型产甲烷古菌甲烷热杆菌属(Methanothermobacter)增至84.3±1.5%;当添加选择性抑制剂CH3F,Methanosaeta丰度分别降至77.1±14.5%,86.4±6.1%和35.8±7.8%,低温菌系Y15中的甲烷八叠球菌属(Methanosarcina)增高(15.7±21%),这类产甲烷古菌具有多种产甲烷代谢途径,M82中Methanoculleus丰度上升到13.6±13.1%,SK中Methanothermobacter丰度增大到48.5±11.2%。【结论】在低温条件下,菌系Y15可能主要通过乙酸裂解完成产甲烷代谢,在中高温条件下,菌系M82和SK中可能存在乙酸互营氧化产甲烷代谢途径,并且甲烷的产生分别通过不同种群的氢营养型产甲烷古菌来完成。
