共查询到19条相似文献,搜索用时 638 毫秒
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介绍了用火焰原子吸收法测定工业硅粉中微量铜的具体方法和过程,同时也给出了最佳实验条件。实验中采用新的样品处理方法,得到了令人满意的结果。其中样品回收率为99.8%~104.0%,相对标准偏差为0.31%~0.38%。本方法在实际应用过程中,简单、快速、准确,易于掌握。 相似文献
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电感耦合等离子体发射光谱法测定食品中铜(Cu)、砷(As)和铅(Pb)的含量 总被引:1,自引:0,他引:1
采用干法灰化进行样品预处理,电感耦合等离子体发射光谱法测定食品中Cu、As、Pb的含量。研究了共存元素对被测元素的影响,选择了适合的工作参数及分析谱线;同时进行了方法检测限、精密度和准确度试验。该方法相对标准偏差小于5%,标准加入回收率为91.4%~102.6%,能旃单、快速、准确、可靠测定食品中重金属(Cu、As、Pb)的含量。 相似文献
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介绍了用火焰原子吸收光谱法测定工业硅粉中微量铜的具体过程,同时也给出了最佳实验条件。实验中采用新的样品处理方法,得到了令人满意的结果。其中样品加标回收率为99.8%-104.0%,相对标准偏差为0.31%-0.38%。本方法在实际应用过程中,操作简便、快速,数据准确,易于掌据。 相似文献
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在大量实验的基础上.建立了在非水条件下快速测定食品中糖精钠的方法,以冰乙酸为溶剂,用高氯酸的冰乙酸标准溶液滴定.RSD在0.92%~2.93%,加标回收率在97.13%~100.3%.实验结果表明,本法定量分析准确,精确度高。可靠性和重现性好而且操作简便,易于推广。 相似文献
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建立了同时测试水中84种VOCs的吹扫捕集一气相质谱测试法,通过对实际样品的测试,验证了方法的可靠性。结果表明84种目标物分离效果较好,方法检出限为0.01~0.52μg/L,工作曲线的线性相关系数为0.977~0.999,在2.5、4、8、10μg/L四个浓度下的加标回收率分别为72.4%~142.0%、77.0%~109.2%、66.9%~124.0%和61.2%~109.7%,综合的平均回收率为79.5%~110.1%,相对标准偏差为0.56%~18.30%。该方法具有良好的准确度和精密度且操作简单,可以满足商业实验室对水中VOCs测定的需要。 相似文献
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建立了食品中邻苯二甲酸酯类化合物的气相色谱-质谱(Gc—Ms)测定方法。以乙酸乙酯和环己烷为萃取溶剂,用溶剂萃取食品中的邻苯二甲酸酯类化合物,采用气相色谱-质谱(GC-MS)进行检测。邻苯二甲酸酯的线性相关系数r〉0.999,对实际加标样品的回收率在85%-115%之间,相对标准偏差(1KSD)在1.6%-8.2%之间,适合于食品中邻苯二甲酸酯类化合物的测定。 相似文献
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ABSTRACT: BACKGROUND: Improvement of traditional methods for dietary assessment is necessary, especially in rural areas where it is more difficult to succeed with self-reporting methods. This study presents and validates a method for improving accuracy when measuring food and nutrient intake of individuals in rural areas. It is called the "Food photography 24-h recall method" (FP 24-hR) and is a modified 24-h recall with the addition of a digital food photography record and a photo atlas. METHODS: The study was carried out in a rural area in the tropical region of Bolivia; 45 women participated. Validation of the method was made by comparing it with a reference method, the Weighed Food Record (WFR). During the FP 24-hR, digital photographs were taken by the subjects of all food consumed during a day and a 24-h recall questionnaire was conducted by an interviewer. An estimate of the amount of food consumed was made using a photo atlas and the photographs taken by the subjects. For validation, comparison was made between the calculations, by both methods, of the levels of food, and nutrient, intake. RESULTS: The comparison was made in 10 food categories; most of which were somewhat underestimated from [MINUS SIGN]2.3% (cassava) to [MINUS SIGN]6.8% (rice), except for beverages (+1.6%) and leafy vegetables (+8.7%), which were overestimated. Spearman's correlation coefficients were highly significant (r from 0.75 for eggs to 0.98 for potato and cassava). Nutrient intakes calculated with data from both methods showed small differences from -0.90% (vitamin C) to -5.98% (fat). Although all nutrients were somewhat underestimated, Pearson[ACUTE ACCENT]s coefficients are high (>0.93 for all) and statistically significant. Bland Altman analysis showed that differences between both methods were random and did not exhibit any systematic bias over levels of food and nutrient intake, with acceptable 95% limits of agreement. CONCLUSION: The FP 24-hR exhibits acceptable differences when compared with a WFR, digital photos are useful as a memory aid for the subjects during 24-h recall and as an estimation tool. The method is suitable for assessing dietary intake among rural populations in developing countries. 相似文献
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HPLC检测食品接触材料中双酚A的含量 总被引:1,自引:0,他引:1
建立并验证了利用HPLC检测食品接触材料中双酚A的含量。样品经3%(质量分数)的乙酸溶液70℃浸泡2h,过滤浸泡液于4℃避光保存,HPLC测试。结果显示,双酚A在0.1008~1008.2μg/mL的浓度范围内线性相关系数r2=0.9999,本方法平均回收率为85.78%~98.12%,相对标准偏差RSD为0.97%~1.61%,该方法检测限(S/N=3)为0.038mg/kg。本方法对于食品接触材料中双酚A的含量检测结果准确,操作方便,快捷,满足企业对该项指标的控制要求。 相似文献