氯仿(CHCl_(3))和溴仿(CHBr_(3))是两种重要的挥发性卤代烃(Volatile halohydrocarbon,VHCs),可通过光化学作用,引起臭氧层破坏和温室效应,影响全球气候变化。以黄河三角洲湿地的优势物种—盐地碱蓬(Suaeda glauca)为研究对象,采用室内...氯仿(CHCl_(3))和溴仿(CHBr_(3))是两种重要的挥发性卤代烃(Volatile halohydrocarbon,VHCs),可通过光化学作用,引起臭氧层破坏和温室效应,影响全球气候变化。以黄河三角洲湿地的优势物种—盐地碱蓬(Suaeda glauca)为研究对象,采用室内盆栽培养来探究不同浓度氮输入水平(CK,对照,6.0 g N m^(-2) a^(-1);1.5N0,低氮处理,9.0 g N m^(-2) a^(-1);3.0N0,高氮处理,18.0 g N m^(-2) a^(-1))对盐地碱蓬以及盆栽微生态系统CHCl_(3)、CHBr_(3)通量特征的影响。结果表明,不同氮梯度下盐地碱蓬CHCl_(3)和CHBr_(3)排放通量均呈现出先降后升的趋势,低浓度1.5N0下可以促进盐地碱蓬CHCl_(3)的释放,高浓度3.0N0则抑制;盐地碱蓬CHCl_(3)、CHBr_(3)气体通量的峰值分别出现在枯萎期与苗期,其主要原因是不同氮梯度刺激了气体消耗与产生之间的平衡以及植物各生长期生长因子的改变。由相关性分析可知,盐地碱蓬CHCl_(3)排放通量受多种因子相互作用,植物根长与CHBr_(3)排放之间存在显著相关性,根部越长,CHBr_(3)的排放通量越低。不同氮梯度下盆栽微生态系统内CHCl_(3)、CHBr_(3)排放通量的变化趋势不同,CHCl_(3)通量为先升后降,CHBr_(3)为先降后升,气体通量的最高值与最低值出现在植物不同生长时期,盆栽微生态系统气体排放通量主要受土壤NH^(+)_(4)-N、NO^(-)_(3)-N、以及植物凋落物等交互作用的影响。展开更多
Metal⁃organic framework(MOF)MIL⁃101 and surface plasmon polariton(SPP)supported gold nanoparti⁃cles(Au NPs)hybrid systems were developed as a highly sensitive and reproducible surface⁃enhanced Raman scat⁃tering(SERS)d...Metal⁃organic framework(MOF)MIL⁃101 and surface plasmon polariton(SPP)supported gold nanoparti⁃cles(Au NPs)hybrid systems were developed as a highly sensitive and reproducible surface⁃enhanced Raman scat⁃tering(SERS)detection platform,in which a green electrostatic self⁃assembly technology was adopted to construct the substrate.In an aqueous solution,the electronegativity of the particles can be used to prepare the composite sub⁃strate without any surface modifier.Due to the enrichment capacity of MIL⁃101 and the electromagnetic enhance⁃ment from Au NPs,the well⁃designed MIL⁃101/Au composites possessed ultrahigh sensitivity with the detection limit of Rhodamine 6G(R6G)as low as 10^(-10) mol·L^(-1).Meanwhile,the substrate exhibits high stability,excellent reproduc⁃ibility,and recyclability.Additionally,the novel substrate can be explored for direct capture,and sensitively detect pesticide residues such as thiram.展开更多
文摘氯仿(CHCl_(3))和溴仿(CHBr_(3))是两种重要的挥发性卤代烃(Volatile halohydrocarbon,VHCs),可通过光化学作用,引起臭氧层破坏和温室效应,影响全球气候变化。以黄河三角洲湿地的优势物种—盐地碱蓬(Suaeda glauca)为研究对象,采用室内盆栽培养来探究不同浓度氮输入水平(CK,对照,6.0 g N m^(-2) a^(-1);1.5N0,低氮处理,9.0 g N m^(-2) a^(-1);3.0N0,高氮处理,18.0 g N m^(-2) a^(-1))对盐地碱蓬以及盆栽微生态系统CHCl_(3)、CHBr_(3)通量特征的影响。结果表明,不同氮梯度下盐地碱蓬CHCl_(3)和CHBr_(3)排放通量均呈现出先降后升的趋势,低浓度1.5N0下可以促进盐地碱蓬CHCl_(3)的释放,高浓度3.0N0则抑制;盐地碱蓬CHCl_(3)、CHBr_(3)气体通量的峰值分别出现在枯萎期与苗期,其主要原因是不同氮梯度刺激了气体消耗与产生之间的平衡以及植物各生长期生长因子的改变。由相关性分析可知,盐地碱蓬CHCl_(3)排放通量受多种因子相互作用,植物根长与CHBr_(3)排放之间存在显著相关性,根部越长,CHBr_(3)的排放通量越低。不同氮梯度下盆栽微生态系统内CHCl_(3)、CHBr_(3)排放通量的变化趋势不同,CHCl_(3)通量为先升后降,CHBr_(3)为先降后升,气体通量的最高值与最低值出现在植物不同生长时期,盆栽微生态系统气体排放通量主要受土壤NH^(+)_(4)-N、NO^(-)_(3)-N、以及植物凋落物等交互作用的影响。
文摘Metal⁃organic framework(MOF)MIL⁃101 and surface plasmon polariton(SPP)supported gold nanoparti⁃cles(Au NPs)hybrid systems were developed as a highly sensitive and reproducible surface⁃enhanced Raman scat⁃tering(SERS)detection platform,in which a green electrostatic self⁃assembly technology was adopted to construct the substrate.In an aqueous solution,the electronegativity of the particles can be used to prepare the composite sub⁃strate without any surface modifier.Due to the enrichment capacity of MIL⁃101 and the electromagnetic enhance⁃ment from Au NPs,the well⁃designed MIL⁃101/Au composites possessed ultrahigh sensitivity with the detection limit of Rhodamine 6G(R6G)as low as 10^(-10) mol·L^(-1).Meanwhile,the substrate exhibits high stability,excellent reproduc⁃ibility,and recyclability.Additionally,the novel substrate can be explored for direct capture,and sensitively detect pesticide residues such as thiram.
