摘要
为解决司法鉴定领域中喷墨打印文件制成时间问题,利用气相色谱-质谱联用法(GC-MS)定性定量分析4种黑色喷墨打印文件墨迹中的挥发性溶剂成分。对同一时间打印的样品进行追踪测试,每间隔一定天数用打孔器取样,提取剂提取后进行GC-MS分析。通过内标法测定样品提取液中各组分的浓度,计算单位长度(mm)墨迹中挥发性溶剂含量C(ng/mm)并作为打印样品老化的定量单位。结果表明,4种打印样品中含有2-吡咯烷酮、1,5-戊二醇、2-甲基-1,3-丙二醇、N-羟乙基-2-吡咯烷酮、甘油和三甘醇6种挥发性溶剂成分。上述成分在文件形成时即开始挥发和转移,含量不断减少至某一数值时趋于稳定。利用测定的历经不同时间的打印样本中溶剂含量数据,建立了单组分溶剂与时间的非线性回归模型以及多组分溶剂与时间的多元线性回归模型,模型评价指标比较结果表明,对于溶剂组分数多的墨水使用多元线性回归模型的预测效果更好。
In order to solve the problem of formation time of inkjet printed documents in forensic field,the volatile components in four models of two brands black inkjet printed documents were quan⁃titatively and qualitatively analyzed by gas chromatography-mass spectrometry(GC-MS).The sam⁃ples printed at one certain time were tracked and tested,at regular intervals the printed samples were punched by a micro punch with a diameter of 0.5 mm and the extract was analyzed by GC-MS.Re⁃tention time and qualitative ions combined with NIST mass spectrometry library were used for qualita⁃tive analysis and internal standard method to determine the concentration of each substance in the ex⁃tract.The content of volatile solvent C(ng/mm)in the ink blot per unit length(mm)was calculated and used as a quantitative unit of aging of printed samples.The results showed that four experimental samples contained six volatile solvent components,including 2-pyrrolidone,1,5-pentanediol,2-methyl-1,3-propylene glycol,N-hydroxyethyl-2-pyrrolidone,glycerol and triethylene glycol.These volatile components began to volatilize and transfer at the moment the printing ink was entried in the paper,and tended to stabilize.Finally,the content continued to decrease to a certain value.Based on the analysis data measured over different time period,two types of exponential functions were used to analyze the diachronic change of volatile solvents and a single component and time non⁃linear regression models including S-curve,Power and Logarithm model,a multi-component and time multiple linear regression model were established to predict the formation time of printed docu⁃ments and compare the effect of prediction.By comparing the evaluation indexes of the models,it was concluded that the prediction effect of the multiple linear regression model is better for the ink with more solvent sets.
作者
王千羽
赵鹏程
崔岚
宋辉
李扬动
张祉悦
WANG Qian-yu;ZHAO Peng-cheng;CUI Lan;SONG Hui;LI Yang-dong;ZHANG Zhi-yue(College of Criminal Science and Technology,Criminal Investigation Police University of China,Shenyang 110035,China)
出处
《分析测试学报》
CAS
CSCD
北大核心
2024年第6期858-865,874,共9页
Journal of Instrumental Analysis
基金
公安部科技强警基础工作计划项目(2022JC03,2023JC05)。
关键词
喷墨打印
文件形成时间
回归模型
气相色谱-质谱联用法
挥发性物质
inkjet printing
document formation time
regression models
gas chromatographymass spectrometry
volatile substances
