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试验结果表明,40%二嗪磷微乳剂防治水稻二化螟效果良好,推荐使用剂量为70-90ml/667m^2,在此范围内,药后5天防效为89.26%。药后21天防效为93.50%。 相似文献
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农药新剂型和助剂的研究开发概况 总被引:7,自引:0,他引:7
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近年来,我国农药发展很快,农药年产量位居世界第二,农药制剂也有所发展,农药品种与制剂的比例已从1986年的1:2上升到1998年的1:10,但仍以乳油、可湿性粉剂等老剂型为主.据统计,1998年我国农药制剂获得登记的品种达1968种,其中乳油919种,可湿性粉剂447种,分别占总量的46.7%和22.7%,如以农药产量计算,则比例更大. 相似文献
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Serious price discrimination emerges with the development of big data and mobile networks,which harms the interests of consumers.To solve this problem,we propose a blockchain-based price consensus protocol to solve the malicious price discrimination faced by consumers.We give a mathematical definition of price discrimination,which requires the system to satisfy consistency and timeliness.The distributed blockchain can make the different pricing of merchants transparent to consumers,thus satisfying the consistency.The aging window mechanism of our protocol ensures that there is no disagreement between any node on the consensus on price or price discrimination within a fixed period,which meets the timeliness.Moreover,we evaluate its performance through a prototype implementation and experiments with up to 100 user nodes.Experimental results show that our protocol achieves all the expected goals like price transparency,consistency,and timeliness,and it additionally guarantees the consensus of the optimal price with a high probability. 相似文献
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