-->分析检测

Research on Optimal Color Measurement Aperture for Light Pillars Pattern of Holographic Paper Based on Dark Pillars Pattern Positioning

YU Shuxin,FENG Rui,FANG Lili,SHAN Yue,YANG Yanhong,SONG Zhengmei — 2022/12/21 18:56:18

In this study， a handheld integrating sphere spectrophotometer （X-Rite Ci64） and a benchtop integrating sphere spectrophotometer （Ci7800） were used to perform multiple color measurements on seven kinds of holographic paper. The results indicated that more accurate paper colors were obtained with the Ci7800 3.5 mm and X-Rite Ci64 6 mm apertures. The spectral difference after multiple measurements was about 0.6， and the minimum spectral difference was only 0.15. And the spectrum fitting coefficient could reach 99%. The average color difference was about 0.5. During the subsequent color measurement of the light pillars pattern of holographic paper， whose color obtained was more accurate by choosing an instrument with a smaller aperture for color instrument.

Determination Method of Migration of Germicides in Food Contact Paper

2022/12/21 18:56:20

A method was established for determination of migration of ten germicides including carbendazim， tebuconazole， propiconazole， cyproconazole， etc. in food contact paper by Ultra High Performance Liquid Chromatography-Tandem Mass Spectrometry. The results showed that the detection limits of this method were from 0.0005 mg/L to 0.025mg/L for aqueous food simulants and from 0.0004 mg/kg to 0.02 mg/kg for olive oil food simulants. The meant recoveries were from 71.7% to 117.7%， with relative standard deviations from 0.3% to 5.2%， indicating that this method was sensitive and accurate， which could be used to precise for safety risk monitor of food contact paper.

Exploration on the Surface Free Energy Testing Method of Paper Literatures

FAN Huiming,LIAO Yunfei,LI Fengyu,HUANG Shanshan,ZHANG Ke,ZENG Deli,LIU Jianan — 2022/12/21 18:56:22

In this paper， the six surface free energy（called surface energy） testing methods of paper literatures were studied. Based on the measured data of surface energy testing method by Zisman， other methods of Neumann， ZDY， HM， OWRK， and OCG were compared to obtain more convenient surface energy testing method of paper literatures with more consistent between theoretical data and measured data. The results showed that the surface energy measured by Zisman method was 26.24 mJ/m². The surface energy would transform into a low value after sizing， and paper was difficult to wet. The results obtained by the Neumann method for measuring the surface energy of paper were relatively reliable， and the Neumann method could simplify the surface energy test to the greatest extent. In large-scale deacidification treatment， the Neumann method could improve the restoration efficiency of antique books and reduce damage to paper. The ZDY method was not suitable for measuring the surface energy of paper because of the large difference between measured data and theoretical data. The HM method gave a low deviation when diiodomethane and propanetriol were chosen as the testing fluids. The OWRK method and OCG method required the selection of appropriate testing fluids to reduce the standard deviation， and if the testing fluids were not selected correctly， conclusions might be drawn that do not correspond to reality.

Research on Prediction Method of Paper Linting and Dusting in Offset Printing Process Based on Image Processing

ZHANG Meng,GUO Daliang,QIU Jiaxin,LIU Bei,YANG Zijie,NIU Yuhao — 2023/1/18 19:09:02

A quantitative prediction method for the problem of paper surface linting and dusting in offset printing process was established in this study. Five different batches of light weight coated paper from a paper enterprise were selected as paper samples， and the relationship between printing resistance and related permeants such as surface performance， particle area and number of linting and dusting was studied. Under the conditions of test method established in the experiment， the print resistance of the paper in the post-processing was negatively correlated with both of the number of large particles （particle area of 0.02~0.3 mm²） and the number of small particles （particle area <0.02 mm²）. By testing the paper samples from another paper enterprise， the predicted print-resistant length value obtained from the print-resistant length prediction curve was consistent with the actual print-resistant length.

Effect of Potential Macular Staining on the Pyrolysis/Combustion Characteristics and Reaction Kinetics of Cigarette Paper

2023/1/18 19:09:04

The effect of staining on the pyrolysis and combustion characteristic of cigarette paper was studied by using thermogravimetric technique. The Coats-Redfern method was employed to compare the kinetic differences in the main weight loss stages of pyrolysis and combustion process of cigarette paper contaminated with different staining. And principal component analysis was conducted based on the thermogravimetric data to explore the feasibility of distinguishing different staining. The results showed that different staining exhibited different adhesion form on the fiber surface of cigarette paper. The pyrolysis and combustion process of each cigarette paper could be divided into four main stages of weight loss. In the pyrolytic process， grease staining could increase the termination temperature and weight loss rate of cellulose decomposition stage， and reduce the weight loss rate of lignin decomposition and coke formation stage. In the combustion process， grease staining significantly reduced the ignition temperature and burnout temperature of cigarette paper. In addition， an opposite effect on the comprehensive combustion characteristics index was observed by grease and flavor contaminants. Thermal decomposition kinetics showed that all the tested staining could reduce the activation energy of thermal decomposition reaction， especially for the grease staining， which changed the reaction mechanism of the thermal decomposition process of cigarette paper. And the reaction activation energy was significantly reduced by grease staining. The principal component analysis based on the pyrolysis and combustion weight loss data showed that the cigarette paper contaminated with grease and flavor/sugar could be effectively distinguished from the original cigarette paper.

Detection and Control of Reconstituted Tobacco Coating Rate Based on CIE Chromaticity System

LI Maoyi,YU Dede,LU Hongliang,MA Pengfei — 2023/1/18 19:09:05

The CIE chromaticity system was used to quantify the color of reconstituted tobacco， and the equation of coating rate detection based on CIE chromaticity system was established through regression analysis， and the quality control model of the production process was formed. The results showed that the color index of reconstituted tobacco could be accurately quantified via detection based on CIE chromaticity color system， and the correlation between the coating rate and color index， including L* and a* was significant， and obvious with b*. The R² of the regression equation was 0.975， F value reached 38.524， the maximum relative error was 0.315%.