Identification of the meta-instable stress state and study of its mechanism and evolution of relevant physical fields would be of great significance for determination of potential seismic risks and estimation of criti...Identification of the meta-instable stress state and study of its mechanism and evolution of relevant physical fields would be of great significance for determination of potential seismic risks and estimation of critical times. In laboratory experiments, that the specimen enters the meta-instable is marked by accelerated stress release. Could we use the experimental result to identify the earthquake in natural conditions? Because the observational data from one station can only reflect the stress state beneath this station, the key problem for identification of the meta-instability is how to recognize regional stress state through observational data from many stations. In this work, we choose the evolution of the temperature field over varied deformation stages during a stick-slip event on a 5 bending fault as an example, and attempt to find the response features of the physical quantity when the fault enters the meta-instable state. We discuss the characteristics of stages for the stress build-up, stress-time process deviating from linearity before instability, meta-instability, instability, and post-instability, respectively. The result shows that the fault instability slide is a conversion process from independent activities of each fault segment to synergism activity. The instability implies completion of the synergism. The stage deviating from linearity is the onset of stress release, and it is also the onset of the synergism. At the meta-instability stages, stress release becomes dominant, while the synergism tends to finish. Therefore, the analysis of the regional overall stress state should not start from individual stations, and instead it should begin with the evolution of the whole deformation field.展开更多
【目的】研究添加助剂对精喹禾灵EC防除棉田禾本科杂草的增效作用,为除草剂减量施用和科学除草提供数据基础。【方法】通过温室盆栽和田间小区试验,在除草剂常规用量、减量20%和减量40%基础上添加助剂,比较精喹禾灵EC对马唐、牛筋草等...【目的】研究添加助剂对精喹禾灵EC防除棉田禾本科杂草的增效作用,为除草剂减量施用和科学除草提供数据基础。【方法】通过温室盆栽和田间小区试验,在除草剂常规用量、减量20%和减量40%基础上添加助剂,比较精喹禾灵EC对马唐、牛筋草等禾本科杂草的防除效果。【结果】盆栽试验中,在推荐的常量用药水平下添加助剂Foxy SG和Fieldor Max EC,精喹禾灵EC对马唐和牛筋草2种禾本科杂草防效提高1.75%~5.78%,精喹禾灵EC减量20%和40%,2种助剂对防效的增效幅度分别为7.95%~10.54%和21.62%~41.63%,Fieldor Max EC的增效作用显著优于Foxy SG,精喹禾灵EC减量40%后添加Fieldor Max EC对禾本科杂草的防效与常量用药防效无显著差异;田间试验中,2种助剂对精喹禾灵EC的减量增效作用与盆栽试验结果相符,常量用药水平下添加Foxy SG和Fieldor Max EC,精喹禾灵EC对禾本科杂草株防效和鲜重防效提高0.83%~4.19%,精喹禾灵EC减量20%和40%,2种助剂对防效的增效幅度分别为1.08%~8.68%和12.06%~37.74%,Fieldor Max EC的增效作用显著优于Foxy SG,精喹禾灵EC减量40%后添加Fieldor Max EC对禾本科杂草的株防效与常量用药株防效无显著差异。【结论】Foxy SG和Fieldor Max EC 2种助剂,对棉田常用的选择性除草剂精喹禾灵EC除草活性有明显提高,减少除草剂使用量后加入助剂可解决防效降低问题,除草剂使用过程中加入高效助剂是实现除草剂减量增效的有效途径。展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos. 40872129, 41172180)
文摘Identification of the meta-instable stress state and study of its mechanism and evolution of relevant physical fields would be of great significance for determination of potential seismic risks and estimation of critical times. In laboratory experiments, that the specimen enters the meta-instable is marked by accelerated stress release. Could we use the experimental result to identify the earthquake in natural conditions? Because the observational data from one station can only reflect the stress state beneath this station, the key problem for identification of the meta-instability is how to recognize regional stress state through observational data from many stations. In this work, we choose the evolution of the temperature field over varied deformation stages during a stick-slip event on a 5 bending fault as an example, and attempt to find the response features of the physical quantity when the fault enters the meta-instable state. We discuss the characteristics of stages for the stress build-up, stress-time process deviating from linearity before instability, meta-instability, instability, and post-instability, respectively. The result shows that the fault instability slide is a conversion process from independent activities of each fault segment to synergism activity. The instability implies completion of the synergism. The stage deviating from linearity is the onset of stress release, and it is also the onset of the synergism. At the meta-instability stages, stress release becomes dominant, while the synergism tends to finish. Therefore, the analysis of the regional overall stress state should not start from individual stations, and instead it should begin with the evolution of the whole deformation field.
文摘【目的】研究添加助剂对精喹禾灵EC防除棉田禾本科杂草的增效作用,为除草剂减量施用和科学除草提供数据基础。【方法】通过温室盆栽和田间小区试验,在除草剂常规用量、减量20%和减量40%基础上添加助剂,比较精喹禾灵EC对马唐、牛筋草等禾本科杂草的防除效果。【结果】盆栽试验中,在推荐的常量用药水平下添加助剂Foxy SG和Fieldor Max EC,精喹禾灵EC对马唐和牛筋草2种禾本科杂草防效提高1.75%~5.78%,精喹禾灵EC减量20%和40%,2种助剂对防效的增效幅度分别为7.95%~10.54%和21.62%~41.63%,Fieldor Max EC的增效作用显著优于Foxy SG,精喹禾灵EC减量40%后添加Fieldor Max EC对禾本科杂草的防效与常量用药防效无显著差异;田间试验中,2种助剂对精喹禾灵EC的减量增效作用与盆栽试验结果相符,常量用药水平下添加Foxy SG和Fieldor Max EC,精喹禾灵EC对禾本科杂草株防效和鲜重防效提高0.83%~4.19%,精喹禾灵EC减量20%和40%,2种助剂对防效的增效幅度分别为1.08%~8.68%和12.06%~37.74%,Fieldor Max EC的增效作用显著优于Foxy SG,精喹禾灵EC减量40%后添加Fieldor Max EC对禾本科杂草的株防效与常量用药株防效无显著差异。【结论】Foxy SG和Fieldor Max EC 2种助剂,对棉田常用的选择性除草剂精喹禾灵EC除草活性有明显提高,减少除草剂使用量后加入助剂可解决防效降低问题,除草剂使用过程中加入高效助剂是实现除草剂减量增效的有效途径。
