老化的报纸纸张结构与组分分析  

Analysis of Structure and Composition of Ageing Newspaper

作　　者：李东旭 尚鑫 李英娟[2] 钱程[3] 陈洁 任晓冬[1] 杨百全[3] LI Dong-Xu;SHANG Xin;LI Ying-Juan;QIAN Cheng;CHEN Jie;REN Xiao-Dong;YANG Bai-Quan(School of Life Sciences,Jilin University,Changchun 130012,China;Jilin Police College,Changchun 130117,China;Certificate Appraisal Center of Public Security Department of Jilin Province,Changchun 130000,China;Criminal Police Detachment of Changchun Public Security Bureau,Changchun 130061,China)

机构地区：[1]吉林大学生命科学学院,长春130012 [2]吉林警察学院,长春130117 [3]吉林省公安厅物证中心,长春130000 [4]长春市公安局刑警支队,长春130061

出　　处：《分析化学》2021年第11期1890-1896,共7页Chinese Journal of Analytical Chemistry

基　　金：公安部法医遗传学重点实验室开放课题(No.2019FGKFKT01)资助。

摘　　要：纸张老化程度的分析是物证鉴定领域的重要研究内容。本研究以1966~2015年的《人民日报》的纸张为样本,采用傅里叶变换红外光谱、X-射线晶体衍射、扫描电子显微镜、原子力显微镜和离子色谱对纸张的结构和组成变化进行了分析。随着保存时间延长,纸张在3000~3600 cm^(-1)的—OH特征峰、2925~3000 cm^(-1)的—C—H特征峰等逐渐减弱,表明纤维素的分子内、分子间作用力逐渐减弱;纸张的结晶度逐渐下降,由80.6%(2015年)降低到71.2%(1966年);纸张的纤维结构逐渐发生断裂、凹陷;纸张表面纤维块状结构逐渐碎片化;Na+含量逐渐降低,K^(+)、PO^(3-)_(4)和Cl^(-)含量逐渐升高。本研究结果表明,随着保存时间延长,报纸纸张的微观结构与组成呈规律性变化。本研究为老化纸张的物证鉴定提供了方法和依据。The analysis of degree of aging paper is an important research topic in the field of identification of physical evidence.The rule of the structure and composition in aging paper of People's daily from 1966 to 2015 were investigated by Fourier transform infrared spectroscopy(FTIR),X-ray crystal diffraction,scanning electron microscope(SEM),atomic force microscope(AFM)and ion chromatography in this work.The result of FTIR showed that the characteristic peaks of—OH(3000-3600 cm^(-1)),—C—H(2925-3000 cm^(-1))got weak in the ageing process,which indicated the intramolecular and intermolecular forces of cellulose weakening gradually.The result of X-ray crystal diffraction showed that the crystallinity of paper decreased from 80.6%in 2015 to 71.2%in 1966.The structure of paper in 2015 was neat and smooth according to the results of SEM.SEM was used to observe the surface of paper and found that the microstructure of paper gradually broke and sunken as time.The result of AFM showed that the fiber structure on the surface of paper was gradually fragmented in the aging process.The contents of potassium ion,sodium ion,phosphate ion and chloride ion in paper of different ages were determined by ion chromatography,and found thatthe content of sodium ion decreased gradually,while the contents of other ions increased in the ageing process.The experimental results showed that the micro-structure and composition of newspaper changed regularly with the prolongation of storage time,which could provide evidence for the identification of aging paper.

关 键 词：老化纸张 微观结构和组成分析 傅里叶变换红外光谱 X-射线晶体衍射 扫描电子显微镜 原子力显微镜 离子色谱 

分 类 号：D918.9[政治法律—法学] O652[理学—分析化学]