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为有效防治危害紫云英的苜蓿叶象甲,笔者测定了5种杀虫剂对叶象甲的田间防治效果。结果表明,每667 m2喷施10%联苯菊酯乳油30 mL防治苜蓿叶象甲幼虫,速效性和持效性优异,药后7 d和14 d的平均防效分别为92.2%和98.2%;喷施60 g/L乙基多杀菌素悬浮剂30 mL和4.5%高效氯氰菊酯乳油30 mL的防效次之,药后14 d平均防效分别为86.5%和69.8%;喷施10%虫螨腈悬浮剂50 mL防治苜蓿叶象甲速效性好,药后7 d平均防效为62.4%;喷施5.7%甲维盐水分散粒剂10 g持效性好,药后14 d平均防效为83.4%。 相似文献
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选择7种生物杀虫剂,于草原蝗虫2~3龄蝗蝻期喷雾,评价田间防治效果,以期为草原蝗虫防控提供高效的生物杀虫剂。结果表明:7种供试杀虫剂对草原蝗虫具有一定的防治效果,药剂种类和处理时间对防效的影响较大。10%多杀菌素悬浮剂对草原蝗虫的防效最好,0.3%印楝素乳油次之,药后5 d的防效分别为85.19%和74.23%。10%多杀菌素悬浮剂、1.5%苦参碱可溶液剂、0.3%印楝素乳油和3%苦参碱水乳剂对草原蝗虫的持效性较好,药后20 d的防效分别为72.02%、70.71%、69.09%和68.06%。建议蝗虫密度大时可优先选择10%多杀菌素悬浮剂进行防治,蝗虫密度低时可选用0.3%印楝素乳油和3%苦参碱水乳剂进行防治。 相似文献
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针对目前防治蔬菜烟粉虱的常用药剂效果下降,不能适应蔬菜绿色防控需求的现状,从近2年国内新登记的杀虫剂中筛选对蔬菜烟粉虱高效、安全药剂,为设施蔬菜烟粉虱的绿色防控提供科学依据。采用茎叶喷雾法研究了5种杀虫剂对设施辣椒烟粉虱的防效及其安全性。结果表明,药后3 d,5%D-柠檬烯可溶液剂125 m L/667m2、5%双丙环虫酯可分散液剂10 m L/667m2、17%氟吡呋喃酮可溶液剂40 m L/667m2、10%溴氰虫酰胺可分散油悬浮剂10 m L/667m2、5%啶虫脒乳油30 m L/667m2对辣椒烟粉虱的校正防效分别为42.86%、86.67%、91.84%、81.43%、68.35%;药后7 d,校正防效分别为52.21%、90.55%、95.57%、86.95%、72.37%。5%双丙环虫酯、17%氟吡呋喃酮、10%溴氰虫酰胺对烟粉虱具有较好的速效性和持效性;5%D-柠檬烯速效性、持效性欠佳,药后7 d校正防效仅达50%以上;啶虫脒作为常规药剂,已被长期广泛使用,防... 相似文献
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应用苏云金芽孢杆菌防治小菜蛾的田间药效试验结果表明:苏云金芽孢杆菌500倍对小菜蛾具有良好防效,施药后3d的防效达73.6%,药后5d的防效达85.5%。 相似文献
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采用喷雾法,研究了8种生物源杀虫剂、2种化学杀虫剂对花椰菜田小菜蛾幼虫的防治效果。结果表明:200 g/L氯虫苯甲酰胺SC 50~66.7 mg/L、150 g/L茚虫威EC 51.7~68.2 mg/L、60 g/L乙基多杀菌素SC 46.2~60 mg/L、1%苦参碱SL 21.3~30.3 mg/L、5%桉油精SL 106.4~125 mg/L处理,药后1 d的防效在73%以上,药后7 d的防效为90%~98%。上述5种杀虫剂可作为防治小菜蛾的轮换药剂在花椰菜生产中推广应用。 相似文献
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Dinesh Singh J. K. Gehlawat Musti S. Rao 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1990,47(2):127-136
Oslefins and diolefins are important intermediates in the petrochemical industry and the future promises a further substantial increase in demand. While several catalysts have been formulated in the past for the abstraction of hydrogen from butenes and propylene, these catalysts are inefficient in the abstraction of first hydrogen from butane. Bismuth molybdates (β and γ-phases) containing iron oxide and supported on alumina are used as catalysts in the present investigation on the oxidative dehydrogenation of n-butane. Effects of catalyst content, temperature and oxygen: n-butane ratio on conversion and selectivity to butadiene and (C4H8 + C4H6) are studied in the following ranges of experimental conditions: β-bismuth molybdate/100 mol support I(K), 3–9; γ-bismuth molybdate/100 mol support I(K), 5-20; temperature, 400–500°C; O2: butane ratio, 0.6:1.7. 相似文献
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A viscometer used to measure the viscosity of 10 μl of a liquid, must be miniaturized down, and the liquid velocity gradient in the channel used to determine the viscosity coefficient. Two major factors that affect the liquid velocity are the mechanical forces exerted by the mechanical motors and electromagnetic forces. In this study, electrowetting on dielectric (EWOD) is adopted to drive liquids. Variously sized electrodes on a chip, and two shapes of channel are employed to measure the velocity gradient to determine the viscosity coefficient. The device is fabricated by microelectromechanical system (MEMS) technology. The dielectric layer used in EWOD has a high dielectric constant, BST (Ba0.7Sr0.3TiO3), to reduce the required applied voltage; its surface is coated with hydrophobic polymer, polytetrafluoro-ethylene (PTFE, Teflon® AF DuPont). Experimental results demonstrate that liquids can be pulled at 660 μm/s in linear channels by applying a voltage of 15 V. 相似文献
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考登钢作为一种高耐候结构钢,广泛应用于各个领域。在火力发电方面,考登钢主要应用在工作环境比较恶劣的烟气加热器和空气预热器中。考登钢表面涂搪的目的就是进一步提高其耐腐蚀性能,延长使用寿命。为了提高考登钢元件的使用寿命,对考登钢表面涂搪瓷的可行性、密着性能、瓷釉、工艺控制、质量保证等方面进行了研究。 相似文献
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研究了温度和pH值对漆酶酶活以及漆酶处理纤维压制纤维板性能的影响。结果表明,pH较低、温度较高时漆酶酶活较高,压制的纤维板强度性能较好。但温度太高(60~80℃),延长加热时间,漆酶稳定性变差,酶活明显降低,压制纤维板的强度下降。 相似文献
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In reexamining medium effects on photochemical reactions, we have emphasized those on unequilibrated excited species such as the Franck-Condon species. Despite recent advances in femtochemistry, such a discussion in molecular photochemistry is uncommon, and the problem remains challenging on account of the extremely short-lived excited species. However, in such cases, a small perturbation resulting from, for example, weak guest-host interactions could turn into a determining factor in dictating the course of a photochemical channel of deactivation. Examples of medium-directed diabatic processes have been examined with this idea in mind. A modified view on rhodopsin photoisomerization is presented along with the consideration that confinement does not necessarily lead to inhibition of reactions of the trapped substrate. 相似文献
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采用密度泛函理论(DFT)考察了丙烷在Pt(111)表面上脱氢生成丙烯的反应机理。通过在Pt(111)面上预吸附一定数量H原子模拟共吸附H对丙烷脱氢过程的影响。结果表明:H共吸附能降低丙烷及其脱氢产物的吸附能,促进丙烯脱附,有利于提高丙烯的选择性;H共吸附会导致丙烷脱氢能垒变大,降低催化剂的脱氢活性;共吸附的影响随着H覆盖率增加而增大。 相似文献