三自由度机器人机械关节设计

多自由度机器人机械关节的研究开发是机器人机械系统设计的重要课题之一,本文从结构设计角度介绍作者关于三自由度机械关系的几种结构原理并对其运动控制等问题加以分析论证。

固相萃取-色谱测定水、沉积物及土壤中氯霉素和3种四环素类抗生素

建立了固相萃取-高效液相色谱（UV）检测水、沉积物和土壤中的氯霉素、土霉素、四环素和金霉素4种抗生素的方法。水样、土壤和沉积物样品的前处理采用EDTA-McIlvaine缓冲溶液提取,用SAX-HLB串联小柱纯化和富集,用丙酮（含10%甲醇）洗脱进一步减小天然有机质的影响。采用乙腈和0.01mol/L草酸溶液作为流动相,8min内分离4种抗生素。测定了贵阳市阿哈湖、南明河和乌江渡水库的水样及沉积物,均有抗生素检出。

A new method of predicting of gas chromatographic retention indices for polychlorinated dibenzofurans (PCDFs)

A new method has been developed to describe the quantitative relationship between molecular structures of PCDFs and their gas chromatographic retention indices on a 30-m fused silica column coated with DB-5 stationary phase. The regression equation is derived with a multiple correlation coefficient greater than 0.9995. The highest residual is 20 index units. The standard deviation is less than 7 index units. Using this regression equation, the retention indices of PCDFs for which data is not available have also been predicted. (C) 2000 Elsevier Science Ltd. All rights reserved.