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昆明太华山气象站建于1935年,是云南省最早建成的气象站,其位置在东经102°37′,北纬24°57′,海拔2358.3米。近年来雷击频繁,致使该站无法正常工作。据统计,该地年平均雷暴日在50日以上,仅1978年和1979年每年就有两次雷击该站屋顶避雷针和10千伏进线,造成设备的损坏。为了解决该站的直击雷保护问题,并开展我国消雷装置的试验研究,云南省电力局试验研究所与昆明气象台合作,在该站建立了60米高的消雷装置。 相似文献
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The investigation on bubble behavior in electric field helps to analyze the mechanism of electric enhancement of boiling heat transfer. Experiments were performed to investigate the bubble deformation in direct current (DC) electric field with bubbles attached to the orifice. The air bubbles were slowly generated in the transformer oil pool at different orifices, so that the effect of flow on bubble shape was eliminated. The results showed that the bubbles were elongated and the departure volume decreased when the electric field was intensified. The major and minor axes, aspect ratio and departure volume increased with increasing the orifice diameter. Both the electric field and orifice size have great influence on bubble behavior. The bubble deformation was also simulated to compare with the experimental results. The numerical and experimental data qualitatively agree with each other. 相似文献
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培养基优化实验表明,马铃薯葡萄糖培养基是干巴菌的最适产糖培养基,菌丝体产量和菌丝体多糖产量分别可达7.56 g/L和0.42 g/L。采用Plackett-Burman试验及响应面试验优化干巴菌多糖的提取工艺,结果表明,极显著影响因素及其最优条件为超声功率400 W、超声时间10 min、醇沉倍数3 倍,优化后多糖得率可达6.98%。体外抗氧化实验证明,干巴菌多糖具有良好的抗氧化活性,并且酶水解(纤维素酶、蜗牛酶)和酸水解(硫酸)均可使多糖的抗氧化能力显著增强。采用逐级酸水解结合柱前衍生高效液相色谱法分析多糖结构,其单糖残基分布规律为:支链末端残基由半乳糖和少量甘露糖构成;半乳糖大多分布于支链外侧及支链末端;葡萄糖是主要单糖组分,主要分布于主链及支链内侧;甘露糖主要分布于支链内侧。本研究为酶水解及酸水解方法在多糖领域中的应用及干巴菌多糖的资源开发提供理论基础。 相似文献
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