Three novel complexes, namely {[La(tapipa)(4,4′-bibp)·(H2O)2]·H2O}n(1),{[La-(tapipa)(H2O)4(OH)]·3 H2O}n(2),[Co(tapipa)(1,4-bbib)]n(3)(tapipa = 5-(3-(tetrazo-5-yl)phenyl)isophthalic acid, 4,4′-bibp = ...Three novel complexes, namely {[La(tapipa)(4,4′-bibp)·(H2O)2]·H2O}n(1),{[La-(tapipa)(H2O)4(OH)]·3 H2O}n(2),[Co(tapipa)(1,4-bbib)]n(3)(tapipa = 5-(3-(tetrazo-5-yl)phenyl)isophthalic acid, 4,4′-bibp = 4,4′-bis(imidazolyl)biphenyl, and 1,4-bbib = 1,4-bis(benzimidazo-1-ly)benzene) have been synthesized under solvothermal conditions and characterized by PXRD, IR,TGA, and so on. Complex 1 presents a 2 D layer structure, which is finally packed into a 3 D supramolecular structure by means of hydrogen bonds;complexes 2 and 3 exhibit 1 D chains and 2 D wavy-type structures, respectively, which are expanded into 3 D supramolecular structures through hydrogen bonds and π-π interactions. Furthermore, the luminescence properties of complex 1 and the variable-temperature magnetic susceptibilities of 3 were investigated. Complex 1 has highly selective sensing for Fe^3+ and Cr2O7^2- ions.展开更多
探究农药施用数量、方式对果园土壤农药残留的影响可以为果树栽培农药减施提供依据。针对陕西长武苹果产区的高频施用农药类型,在4月(花期)和8月(套袋期)对11种农药土壤残留浓度进行了调查。研究结果表明,表层土壤的农药残留浓度范围为N...探究农药施用数量、方式对果园土壤农药残留的影响可以为果树栽培农药减施提供依据。针对陕西长武苹果产区的高频施用农药类型,在4月(花期)和8月(套袋期)对11种农药土壤残留浓度进行了调查。研究结果表明,表层土壤的农药残留浓度范围为N/D^887.9 ng g^-1dw,检出率均大于78%,其中8种农药的表层土壤残留检出率为100%。喷施吡虫啉和戊唑醇会在短期内显著提升表层土壤该两种农药残留水平。由于农户喷施农药行为具有相似性,致使在4月和8月试验区和对照区的土壤残留特征相似,农药残留不同月份的差异主要受到农户用药习惯和用药量的影响。农药主要残留于表层(0~5 cm)土壤。因喷施过程中农药更多地落到树木覆盖稀疏地面,故试验区和对照区果园地面农药残留均呈点状分布,致使表层土壤和残留聚集点具有更高的生态风险。在11种常用农药中,吡虫啉和多菌灵的浓度较低、但生物(蚯蚓)毒性大,使计算得到的风险商(RQ)值大于1,成为环境风险高于其他农药的种类。展开更多
基金supported by the international Scientific and Technological Cooperation Projects of Shanxi Province(201803D421080)
文摘Three novel complexes, namely {[La(tapipa)(4,4′-bibp)·(H2O)2]·H2O}n(1),{[La-(tapipa)(H2O)4(OH)]·3 H2O}n(2),[Co(tapipa)(1,4-bbib)]n(3)(tapipa = 5-(3-(tetrazo-5-yl)phenyl)isophthalic acid, 4,4′-bibp = 4,4′-bis(imidazolyl)biphenyl, and 1,4-bbib = 1,4-bis(benzimidazo-1-ly)benzene) have been synthesized under solvothermal conditions and characterized by PXRD, IR,TGA, and so on. Complex 1 presents a 2 D layer structure, which is finally packed into a 3 D supramolecular structure by means of hydrogen bonds;complexes 2 and 3 exhibit 1 D chains and 2 D wavy-type structures, respectively, which are expanded into 3 D supramolecular structures through hydrogen bonds and π-π interactions. Furthermore, the luminescence properties of complex 1 and the variable-temperature magnetic susceptibilities of 3 were investigated. Complex 1 has highly selective sensing for Fe^3+ and Cr2O7^2- ions.
文摘探究农药施用数量、方式对果园土壤农药残留的影响可以为果树栽培农药减施提供依据。针对陕西长武苹果产区的高频施用农药类型,在4月(花期)和8月(套袋期)对11种农药土壤残留浓度进行了调查。研究结果表明,表层土壤的农药残留浓度范围为N/D^887.9 ng g^-1dw,检出率均大于78%,其中8种农药的表层土壤残留检出率为100%。喷施吡虫啉和戊唑醇会在短期内显著提升表层土壤该两种农药残留水平。由于农户喷施农药行为具有相似性,致使在4月和8月试验区和对照区的土壤残留特征相似,农药残留不同月份的差异主要受到农户用药习惯和用药量的影响。农药主要残留于表层(0~5 cm)土壤。因喷施过程中农药更多地落到树木覆盖稀疏地面,故试验区和对照区果园地面农药残留均呈点状分布,致使表层土壤和残留聚集点具有更高的生态风险。在11种常用农药中,吡虫啉和多菌灵的浓度较低、但生物(蚯蚓)毒性大,使计算得到的风险商(RQ)值大于1,成为环境风险高于其他农药的种类。
