汽油、煤油、柴油是由原油加工而成,但其相应馏程特征有所不同,其中汽油的沸程约为35~205 ℃,煤油的沸程约为140~250 ℃,柴油的沸程约为180~370 ℃,同时,其碳链长度有所不同,汽油在C7～C11范围内,煤油在C12～C15范围内,柴油在C15～C18范围内,由于其碳数分布特征有所差异,其荧光光谱也相应有所差别,这是对三类不同油种进行识别与定量检测的基础.由于海洋时常发生油类污染,监测海洋中油类有机物的含量十分重要,采用拟Monte-Carlo方法计算三维荧光光谱特征峰幂次积分,结合最优算法求解最佳特征峰数量及积分区域范围,利用BFGS法解非线性方程组,提出一种光谱重叠的多种矿物油混合物组分含量测定的方法.由于对选定特征区域内确定点列对应峰值的幂次进行累加,对荧光谱线微小变化敏感,从而对组分含量微小变化敏感.同时由于点列的选取,相比于单点测量法,在一定程度上减小了随机误差的影响,可以进一步提高测量灵敏度.以煤油、柴油、汽油为研究对象,将单一油种视为整体,不考虑每种油的具体组分,测量单一油种及混合物的三维荧光光谱及等高线图谱,经最优算法选择六个特征峰进行特征峰幂次积分,测定混合油中组分含量,与峰值法,均值法等单点测量方法相比较,测量灵敏度提高约50倍,实现了混合物组分含量的高精度测量,为不需化学分离直接测定光谱重叠混合物组分含量提供了一种实用算法.

Gasoline,kerosene,diesel is processed by crude oil with different distillation range.The boiling range ofgasoline is 35~205 ℃.The boiling range of kerosene is 140~250 ℃.And the boiling range of diesel is 180~370 ℃.At the same time,the carbon chain length of differentmineral oil is different.The carbon chain length of gasoline is within the scope of C7 to C11.The carbon chain length of kerosene is within the scope of C12 to C15.And the carbon chain length of diesel is within the scope of C15 to C18.The recognition and quantitative measurement of three kinds of mineral oil is based on different fluorescence spectrum formed in their different carbon number distribution characteristics.Mineral oil pollution occurs frequently,so monitoringmineral oil content in the ocean is very important.A new method of components content determination of spectra overlapping mineral oil mixture is proposed,with calculation of characteristic peak power integrationof three-dimensional fluorescence spectrum by using Quasi-Monte Carlo Method,combined with optimal algorithm solving optimum number of characteristic peak and range of integral region,solving nonlinear equations by using BFGS(a rank to two update method named after its inventor surname first letter,Boyden,Fletcher,Goldfarb and Shanno) method.Peak power accumulation of determined points in selected area is sensitive to small changes of fluorescence spectral line,so the measurement of small changes of component content is sensitive.At the same time,compared with the single point measurement,measurement sensitivity is improved by the decrease influence of random error due to the selection of points.Three-dimensional fluorescence spectra and fluorescence contour spectra of single mineral oil and the mixture are measured by taking kerosene,diesel and gasoline as research objects,with a single mineral oil regarded whole,not considered each mineral oil components.Six characteristic peaks are selected for characteristic peak power integration to determine components content of mineral oil mixture of gasoline,kerosene and diesel by optimal algorithm.Compared with single point measurement of peak method and mean method,measurement sensitivity is improved about 50 times.The implementation of high precision measurement of mixture components content of gasoline,kerosene and diesel provides a practical algorithm for components content direct determination of spectra overlapping mixture without chemical separation.