Methods:To consider Sugarcane total alkane alcohol as effective part objective, total alkane alcohol and octacosanol as investigationindex, determine content by gas chromatography method.
Through field investigation and soil fertility index analysis, causes and mechanism of fertility degradation of black soil in the Songliao Plain were explored.
通过田间调查和土壤肥力指标分析,探讨了松辽平原玉米带黑土肥力退化的原因和机理。
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Objective to evaluate the effect to caries of the fixed appliance by the investigation of plaque index on the crown surface of teeth at the different stages.