Biochar derived from partial combustion of vegetation is ubiquitous and potentially effective in sequestration of environmental contaminants. Biochars were prepared by burning of red gum （Eucalyptus spp.） woodchips ...Biochar derived from partial combustion of vegetation is ubiquitous and potentially effective in sequestration of environmental contaminants. Biochars were prepared by burning of red gum （Eucalyptus spp.） woodchips at 450 and 850℃ （labeled as BC450 and BC850）. These two biochars were found to possess markedly different properties in terms of surface area and porosity. Short-term equilibration tests （24 hr） were conducted to assess the sorption-desorption behavior of pyrimethanil in the soil amended with various amounts of biochar of each type, with a special focus on the desorption behavior of the sorbed pesticide through four times successive desorption by dilution. Sorption coefficient and isotherm nonlinearity of the amended soils progressively increased with the content of biochar in the soil. Biochar BC850 with higher surface area and microporosity showed a stronger effect on the reversibility of sorption pesticide. The soils amended with 5% BC450 and 1% BC850 had nearly the same sorption capacity for pyrimethanil; however, their desorption processes were very different with 13.65% and 1.49% of the sorbed pesticide being released, respectively. This study suggested that biochar in soil could be an important factor for immobilization of a pesticide and thus affecting its environment fate in soil.展开更多
Low-temperature heat capacities of pyrimethanil decylate （ C22 H33 N3 O2 ） were precisely measured with an automated adiabatic calorimeter over the temperature range from 78 to 373 K. The sample was observed to melt...Low-temperature heat capacities of pyrimethanil decylate （ C22 H33 N3 O2 ） were precisely measured with an automated adiabatic calorimeter over the temperature range from 78 to 373 K. The sample was observed to melt at （311.04 ± 0.06） K. The molar enthalpy and entropy of fusion as well as the chemical purity of the compound were determined to be（45876± 12） J/mol, （147. 50 ±0. 05） J. mol^-1 · K^-1 and （99. 21 ±0. 03）% （mass fraction）, respectively. The extrapolated melting temperature for the absolutely pure compound obtained from fractional melting experiments is （311. 204±0. 035 ） K.展开更多
Seven pyrimethanil salts were synthesized by organic base containing nitrogen atom reacting with substituted pyridine acids. They are reported for the first time. Their structures have been confirmed by IR, ^1H NMR an...Seven pyrimethanil salts were synthesized by organic base containing nitrogen atom reacting with substituted pyridine acids. They are reported for the first time. Their structures have been confirmed by IR, ^1H NMR and elemental analysis. The preliminary toxicity tests indicated that most of them exhibited excellent fungicidal activities. The relationship between the structures and the fungicidal activities of the compounds was discussed.展开更多
监测月季灰霉病抗药性发生现状,探索防控药剂的应用技术。病原鉴定采用分子鉴定和形态学鉴定法,抗药性监测采用菌落生长区分剂量法,田间试验采用喷雾法。3省份采集分离的月季灰霉病菌株均为灰葡萄孢菌。抗性监测结果表明,采集的月季灰...监测月季灰霉病抗药性发生现状,探索防控药剂的应用技术。病原鉴定采用分子鉴定和形态学鉴定法,抗药性监测采用菌落生长区分剂量法,田间试验采用喷雾法。3省份采集分离的月季灰霉病菌株均为灰葡萄孢菌。抗性监测结果表明,采集的月季灰霉病菌对多菌灵、嘧菌酯和戊唑醇的抗性频率分别为66.67%、50%和77.78%,应降低使用频次。田间药效试验结果表明,推荐剂量下啶酰菌胺和嘧霉胺对月季灰霉病的防效分别为70%~88%和70%~84%,两者在江苏的防效均>80%。植物安全性试验结果表明,啶酰菌胺在有效剂量225、450、900 g a.i./hm2嘧霉胺在有效剂量800、1600、3200 g a.i./hm2范围内对月季安全。基于本研究成果,建议生产上可使用啶酰菌胺和嘧霉胺防控月季灰霉病,注意轮换用药。展开更多
文摘Biochar derived from partial combustion of vegetation is ubiquitous and potentially effective in sequestration of environmental contaminants. Biochars were prepared by burning of red gum （Eucalyptus spp.） woodchips at 450 and 850℃ （labeled as BC450 and BC850）. These two biochars were found to possess markedly different properties in terms of surface area and porosity. Short-term equilibration tests （24 hr） were conducted to assess the sorption-desorption behavior of pyrimethanil in the soil amended with various amounts of biochar of each type, with a special focus on the desorption behavior of the sorbed pesticide through four times successive desorption by dilution. Sorption coefficient and isotherm nonlinearity of the amended soils progressively increased with the content of biochar in the soil. Biochar BC850 with higher surface area and microporosity showed a stronger effect on the reversibility of sorption pesticide. The soils amended with 5% BC450 and 1% BC850 had nearly the same sorption capacity for pyrimethanil; however, their desorption processes were very different with 13.65% and 1.49% of the sorbed pesticide being released, respectively. This study suggested that biochar in soil could be an important factor for immobilization of a pesticide and thus affecting its environment fate in soil.
文摘Low-temperature heat capacities of pyrimethanil decylate （ C22 H33 N3 O2 ） were precisely measured with an automated adiabatic calorimeter over the temperature range from 78 to 373 K. The sample was observed to melt at （311.04 ± 0.06） K. The molar enthalpy and entropy of fusion as well as the chemical purity of the compound were determined to be（45876± 12） J/mol, （147. 50 ±0. 05） J. mol^-1 · K^-1 and （99. 21 ±0. 03）% （mass fraction）, respectively. The extrapolated melting temperature for the absolutely pure compound obtained from fractional melting experiments is （311. 204±0. 035 ） K.
基金Project supported by the Natural Science Foundation of Shanxi Province （No. 2001H11） and the Project of Northwest University.
文摘Seven pyrimethanil salts were synthesized by organic base containing nitrogen atom reacting with substituted pyridine acids. They are reported for the first time. Their structures have been confirmed by IR, ^1H NMR and elemental analysis. The preliminary toxicity tests indicated that most of them exhibited excellent fungicidal activities. The relationship between the structures and the fungicidal activities of the compounds was discussed.
文摘监测月季灰霉病抗药性发生现状,探索防控药剂的应用技术。病原鉴定采用分子鉴定和形态学鉴定法,抗药性监测采用菌落生长区分剂量法,田间试验采用喷雾法。3省份采集分离的月季灰霉病菌株均为灰葡萄孢菌。抗性监测结果表明,采集的月季灰霉病菌对多菌灵、嘧菌酯和戊唑醇的抗性频率分别为66.67%、50%和77.78%,应降低使用频次。田间药效试验结果表明,推荐剂量下啶酰菌胺和嘧霉胺对月季灰霉病的防效分别为70%~88%和70%~84%,两者在江苏的防效均>80%。植物安全性试验结果表明,啶酰菌胺在有效剂量225、450、900 g a.i./hm2嘧霉胺在有效剂量800、1600、3200 g a.i./hm2范围内对月季安全。基于本研究成果,建议生产上可使用啶酰菌胺和嘧霉胺防控月季灰霉病,注意轮换用药。
