目的 通过对比高精度三维测量技术与人工测量实验结果,对高精度三维测量技术测量不同材料的常用食品接触材料表面积的准确性和精确性作出评价.方法 以6大类24种常用食品接触材料为例,采用高精度三维测量技术计算材料表面积并与人工测量数据进行对比.结果 人工与高精度三维测量技术的常用食品接触材料表面积测量相对标准偏差在6％以内.结论 高精度三维测量技术测量结果稳定,在不同材质常用食品接触材料表面积测量中可保证一定精度且具有广泛适用性,具有稳定可靠的应用前景.

Objective Toinvestigate and establish the best method for the determination of the polyolefin resin xylene and n-hexane solvent extracts.MethodsThe best experimental program was obtained by investigating the effects of the ratio of samples' mass to solvent volume, filtering method, sample particle size, evaporative drying method, residue drying method and drying time on n-hexane and xylene solvent extracts of polyolefin resin.Results The optimal experimental conditions were as follows: the ratio of samples' mass to solvent volume was 1 g/100 mL, the sample particle size was less than 8 mesh holes (sample particle size of xylene extract could not be limited), xylene solvent extract could not add antioxidants, filtering methods of n-hexane solvent extract and xylene solvent extract were respectively paper filtration and vacuum filtration with Buchner funnel, evaporative drying method was water bath, and drying condition of residue was in ordinary oven for 2 h.ConclusionThe same test results are obtained under optimal experimental conditions and standard conditions. However, optimal experimental conditions are less costly, and the operation is more simple and fast.

1引言在食品包装外表面总是印刷着各种精美图案与标签,虽然它们并未与食品直接接触,但是其中的低沸点物质非常容易渗透并迁移至食品当中,从而引起被包装食品的污染,造成食品安全问题。UV固化墨由于不含有机溶剂,再加上它具有固化快、可常温处理、对环境污染低等优点而被广泛用于食品包装印刷行业,尤其是各种纸基食品包装材料的印刷。作为光固化体系的关键组成部分,光引发剂是不可替代的成分,2-

为满足客户需求,检测机构越来越多地应用非标准检测方法,方法确认是保证非标准方法检测结果准确性的关键控制要素之一.通过对美国分析化学家协会AOAC、国际理论与应用化学联合会IUPAC、加拿大标准理事会SCC等国际组织的方法确认技术进行研究,并结合我国非标准方法确认的现状,从加快非标准方法确认的相关政策研究、完善我国非标准方法确认的标准化体系、加强对非标准方法确认的监管力度、加强对相关人员的技术培训等方面探讨完善我国非标准方法管理的长效机制.

本文通过对美国分析化学家协会AOAC国际组织的检测方法体系框架、检测方法确认程序和检测方法确认和验证要求进行分析、研究，探讨AOAC方法确认体系对我国方法确认政策和技术的启示。

Object:To develop a method for the determination of 1,4-dichlorobenzene p-dichlorobenzene in aqueous food simulants of food contact materials by using high-performance liquid chromatography. Methods:The samples were extracted by distilled water, 3%(w/v) acetic acid aqueous solution, 4%(v/v) acetic acid aqueous solution, 10%(v/v) ethanol aqueous solution, 20%(v/v) ethanol aqueous solution and 50%(v/v) ethanol aqueous solution. The extract was separated on a Agilent SB-C18 analytical column with a mixture of methanol-water(70/30 by volume) as the mobile phase, and detected on the ultraviolet detector at a wavelength of 223 nm. Results:The limit of detection(S/N=3) for 1,4-dichlorobenzene p-dichlorobenzene in six aqueous food simulants was up to 0.05 mg/L with a good linear correlation (r≥0.9998) in the range of 0.10 mg/L~25.0 mg/L. The mean recovery of the compound at three different spiked levels were 89.0%~105.0%, with the relative standard deviation (n=6) of 0.88%~7.91%. Conclusion:This method is simple, rapid and accurate. Besides, it can satisfy the inspection of 1,4-dichlorobenzene p-dichlorobenzene in food contact materials.

A rapid determination method of 6 Common phthalate esters(PAEs) in plastic slipcase was developed,which took dichloromethane as extraction solvent,extracted PAEs with ultrasonic,and detected PAEs by gas chromatography-mass spectrometry(GC-MS).Then,contamination situation of PAEs in plastic slipcase of students was studied through determining samples from market.The results showed that high concentration PAEs were generally detected in polyvinyl chloride(PVC) plastic slipcase,and the major PAE was di-2-ethylhexyl phthalate(DEHP).

A rapid determination method for six kinds of common phthalate esters(PAEs) in student plastic slipcase was established,the PAEs were extracted from samples by ultrasonic extraction with dichloromethane and analyzed by gas chromatography-mass spectrometry(GC-MS).The results show that high concentration PAEs are found in polyvinyl chloride(PVC) plastic slipcase that available in the market,and its main ingredient is di-2-ethylhexyl phthalate(DEHP).And the method shows high extraction efficiency,higher recovery,wide linear range and good reproducibility.

比较了水萃取-气相色谱法和水/三氯甲烷2次萃取-气相色谱-质谱法在检测皮革中,N,N-二甲基甲酰胺(DMF)过程中的特点,对2种方法的回收率、准确度、检出限、检测过程时间等指标进行了评价.结果表明:气相色谱法简单快速,检测过程时间小于1h,检测限能够满足标准要求,但气相色谱-质谱法在定性确证中具有不可替代的作用.