航运联盟新阶段集装箱运输网络优化

为更好地配置航运资源,以互联网环境为背景,针对传统航运受班期、航次和船舶数量约束的缺陷,采用数据挖掘与分析的方法,将枢纽港与支线港口作为首要影响因子,构造了航运联盟新阶段的集装箱运输网络优化模型.在此基础上进一步综合分析了数据整合的重要性.模型分为两部分,以成本最小为目标,首先确定枢纽港,再根据各港口需求分配船舶.联盟使得船舶的运力更大,满载率更高.既可以有效配置资源,又可以显著降低成本,充分体现了规模经济的作用.     

气相色谱法（毛细管柱和填充柱）测定农作物中增塑剂DEHP的残留量

This paper describes the determination of the plasticizer DEHP residues in plants and seeds of crops bygas chromatography with capillary and packed columns. DEHP recovery rate was over 90%with high-speedand low cost.This method,especially with packed column is very suitable for the determination of phthalates.