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放蜂方式对松毛虫赤眼蜂田间防效的影响
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作者 张晨 马巾超 +2 位作者 刘旭东 齐振阳 王宇 《黑龙江农业科学》 2024年第10期27-33,共7页
为提高赤眼蜂田间防治效果,降低释放成本,通过测定松毛虫赤眼蜂(Trichogramma dendrolimi)在两种放蜂方式[蛹后期释放、混合生育期释放(即预蛹期、蛹中期和蛹后期)],6个时间段(释放后1~6 d),5个距离点(0,5,10,15,20和25 m)下的实际防效... 为提高赤眼蜂田间防治效果,降低释放成本,通过测定松毛虫赤眼蜂(Trichogramma dendrolimi)在两种放蜂方式[蛹后期释放、混合生育期释放(即预蛹期、蛹中期和蛹后期)],6个时间段(释放后1~6 d),5个距离点(0,5,10,15,20和25 m)下的实际防效,明确放蜂方式对松毛虫赤眼蜂田间寄生能力的影响。结果表明,单独释放松毛虫赤眼蜂(Td)蛹后期时,Td仅可在放蜂后3 d内对田间不同距离的玉米螟卵块进行寄生,各距离点寄生率均随放蜂时间增加而降低。在相同放蜂时间,随着距离的增加,寄生率均呈下降趋势。而混合释放预蛹期、蛹中期和蛹后期释放Td,可以在6 d内对田间玉米螟卵块进行寄生。比较两种放蜂方式发现,在释放Td 3 d后,混合释放的Td表现出更好的扩散能力。由此得出,松毛虫赤眼蜂适合采用混合释放方式。 展开更多
关键词 放蜂方式 松毛虫赤眼蜂 玉米螟 田间防效
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天牛克星——川硬皮肿腿蜂 被引量:3
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《四川林业科技》 北大核心 2000年第3期79-80,共2页
关键词 天牛天敌 川硬皮肿腿蜂 应用 放蜂方式
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Study of Multilayer Flow Insulation Utilizing Open-Cellular Porous Plates
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作者 P. Khantikomol S. Saito T. Yokomine 《Journal of Energy and Power Engineering》 2010年第11期21-29,共9页
To improve the performance of the single layer flow insulation system utilizing open-cellular porous plate, the multilayer porous gas enthalpy-radiation converter is proposed and investigated experimentally and theore... To improve the performance of the single layer flow insulation system utilizing open-cellular porous plate, the multilayer porous gas enthalpy-radiation converter is proposed and investigated experimentally and theoretically. Two open-cellular porous materials with different porosity pore per inch and surface reflectivity have been examined. Each porous plate has the same thickness of a half of the single layer one. Both porous materials are not combined continuously but divided by free space. For the prediction model, two energy equations of the fluid and solid phases are employed, in which the convective heat transfer between both phases is described based on the empirical volumetric heat transfer coefficient. In addition, the radiative transfer equations are resolved by Pj approximation. When an equivalent blackbody radiation temperature of the radiation coming from the upstream region exceeds inlet gas temperature, use of a high reflective porous plate on the upstream side and a low reflective porous plate on the downstream side is quite effective to increase gas temperature drop across the converter. the multilayer porous converter should be made of pure scattering and porous layer, respectively. In order to obtain maximum gas temperature drop in that case, pure absorbing porous plate as the upstream and downstream 展开更多
关键词 Flow insulation open-cellular porous gas enthalpy-radiation converter gas temperature drop.
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