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Linux操作系统以其实时、可裁剪、稳定、源代码公开等特性在基于嵌入式微机系统的控制领域里得到了广泛的应用.本文介绍了如何使用MiniGUI建立楼宇安全系统多层菜单图形控制界面的方法,不但能为控制提供友好的图形界面,而且以MiniGUI轻量级的特点使Linux的实时性得到充分的发挥. 相似文献
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The importance of soil organic carbon (SOC) under forests in the global carbon cycle depends on the stability of the soil carbon and
its availability to soil microbial biomass. We investigated the e ects of successive rotations of Chinese fir (Cunninghamia lanceolata
(Lamb.) Hook) plantations on the stability of SOC and its availability to microbes by adopting the two-step hydrolysis with H2SO4
and density fractionation. The results showed that successive rotations of Chinese fir decreased the quantity of total SOC, recalcitrant
fraction, and carbohydrates in Labile Pool I (LP I), and microbial properties evidently, especially at 0–10 cm horizon. However, cellulose
included in Labile Pool II (LP II) and the cellulose/total carbohydrates ratio increased in successive rotations of Chinese fir. The noncellulose
of carbohydrates included in LP I maybe highly available to soil microbial biomass. Hence the availability of SOC to microbial
biomass declined over the successive rotations. Although there was no significant change in recalcitrance of SOC over the successive
rotations of Chinese fir, the percentage of heavy fraction to total SOC increased, suggesting that the degree of physical protection for
SOC increased and SOC became more stable over the successive rotations. The degradation of SOC quality in successive rotation soils
may be attributed to worse environmental conditions resulted from disturbance that related to “slash and burn” site preparation. Being
highly correlated with soil microbial properties, the cellulose/total carbohydrates ratio as an e ective indicator of changes in availability
of SOC to microbial biomass brought by management practices in forest soils. 相似文献
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