The effect of particle size on the recalcitrance of biochar against oxidation has been regarded as one of the most important factors influencing its stability and transportation in soils. Little is known about the pec...The effect of particle size on the recalcitrance of biochar against oxidation has been regarded as one of the most important factors influencing its stability and transportation in soils. Little is known about the peculiar stability of different particle sizes under chemical oxidation conditions. In this study, several sizes of biochar particles derived from beanpod were produced,and their stabilities were tested by using acid dichromate and hydrogen peroxide. We discovered that the 60-100 mesh size of particles produced at 400 and 500 ℃ showed the least carbon loss under the oxidation of both dichromate and hydrogen peroxide. In addition, this particle size also shows great stability at 600 and 700 ℃, but this stability was not observed below 300 °C for all temperature-dependent biochars. Medium-sized particles composed of exclusively heterogeneous components produced a biochar at temperatures over 400 ℃ with comparatively stronger chemical anti-oxidation characteristics. The chemical recalcitrance of biochar should be reevaluated based on particle size before soil application.展开更多
The Cydia pomonella granulovirus (CpGV) has been used for many years as biological agent for codling moth control in apple orchards. Resistance to the Mexican strain of CpGV was detected in orchards in Germany, France...The Cydia pomonella granulovirus (CpGV) has been used for many years as biological agent for codling moth control in apple orchards. Resistance to the Mexican strain of CpGV was detected in orchards in Germany, France and Italy. A laboratory insect colony was started from insects collected in a French resistant orchard. It was named RGV. Various virus isolates were identified as active against this resistant insect colony. Field tests were carried out in 2007 to test if the two virus isolates CpGV-I12 and NPP-R1 were effective in the field. Although these virus isolates were not able to reduce insect caused fruit damages, they significantly reduced the overwintering insect populations. NPP-R1 was subjected to eight passages on RGV larvae (NPP-R1.8) that improved its biological activity on RGV larvae. 2008 field trials were set up to test this improved virus strain, compared to CpGV-I12 and Madex plus active on RGV. These tests confirmed the ability to control both in susceptible and resistant insect populations.展开更多
基金Supported by the Provincial Basic Research Program of Hebei Education Department(ZD2015110)the National Special Project on Key Technologies and Demonstration of Wetland Ecological Restoration in the Haihe River Basin(2014ZX07203008)the Fund of the University of Hebei Engineering(Grants 20120169)
文摘The effect of particle size on the recalcitrance of biochar against oxidation has been regarded as one of the most important factors influencing its stability and transportation in soils. Little is known about the peculiar stability of different particle sizes under chemical oxidation conditions. In this study, several sizes of biochar particles derived from beanpod were produced,and their stabilities were tested by using acid dichromate and hydrogen peroxide. We discovered that the 60-100 mesh size of particles produced at 400 and 500 ℃ showed the least carbon loss under the oxidation of both dichromate and hydrogen peroxide. In addition, this particle size also shows great stability at 600 and 700 ℃, but this stability was not observed below 300 °C for all temperature-dependent biochars. Medium-sized particles composed of exclusively heterogeneous components produced a biochar at temperatures over 400 ℃ with comparatively stronger chemical anti-oxidation characteristics. The chemical recalcitrance of biochar should be reevaluated based on particle size before soil application.
基金supported by the French Research Agency (ANR-06-RIB-003-02) and by NPP
文摘The Cydia pomonella granulovirus (CpGV) has been used for many years as biological agent for codling moth control in apple orchards. Resistance to the Mexican strain of CpGV was detected in orchards in Germany, France and Italy. A laboratory insect colony was started from insects collected in a French resistant orchard. It was named RGV. Various virus isolates were identified as active against this resistant insect colony. Field tests were carried out in 2007 to test if the two virus isolates CpGV-I12 and NPP-R1 were effective in the field. Although these virus isolates were not able to reduce insect caused fruit damages, they significantly reduced the overwintering insect populations. NPP-R1 was subjected to eight passages on RGV larvae (NPP-R1.8) that improved its biological activity on RGV larvae. 2008 field trials were set up to test this improved virus strain, compared to CpGV-I12 and Madex plus active on RGV. These tests confirmed the ability to control both in susceptible and resistant insect populations.