Determination and identification of titanium dioxide nanoparticles in confectionery foods,marketed in South Korea,using inductively coupled plasma optical emission spectrometry and transmission electron microscopy

Food-grade titanium dioxide (TiO₂) is a common and widespread food additive in many processed foods, personal care products, and other industrial categories as it boosts the brightness and whiteness of colours. Although it is generally recognised as safe for humans, there is a growing interest in the health risks associated with its oral intake. This study quantified and identified TiO₂ nanoparticles present in confectionery foods, which are children’s favourite foods, with inductively coupled plasma optical emission spectrometry (ICP-OES) and transmission electron microscopy (TEM). A reliable digestion method using hot sulphuric acid and a digestion catalyst (K₂SO₄:CuSO₄ = 9:1) was suggested for titanium analysis. Validations of the experimental method were quite acceptable in terms of linearity, recoveries, detection limits, and quantification limits. Of all the 88 analysed foods, TiO₂ was detected in 19 products, all except three declared TiO₂ in their labelling. The mean TiO₂ content of candies, chewing gums, and chocolates were 0.36 mg g^?1, 0.04 mg g^?1, and 0.81 mg g^?1, respectively. Whitish particles isolated from the confectionery foods were confirmed as TiO₂ nanoparticles via TEM and energy dispersive X-ray spectroscopy (EDX), in which nanosized particles (<100 nm) were identified.     

ICP-OES测定西藏铜矿浸出液中铜铅锌等8种矿物组分

电感耦合等离子体光谱法测定西藏铜矿浸出液中8种矿物组分,讨论了元素分析谱线选择、背景校正等因素。结果表明,在高海拔地区仪器参数优化条件下,元素间也没有干扰且该方法快速,准确可靠,各元素检出限5.6~42μg·m L-1之间,加标回收率为92.5%~106%,相对标准偏差RSD均小于1.0%,适用于高海拔条件下对铜矿浸出液的日常检测。     

Biosorbents based on pine sawdust and malt sprouts for preconcentration and ICP-OES determination of nonferrous,heavy, and precious metals in the environmental samples

Pine sawdust and malt sprouts modified with orthophosphoric acid and carbamide have been proposed for solid-phase extraction (SPE) of nonferrous, heavy, and precious metals and their subsequent determination in the environmental samples by inductively coupled plasma optical emission spectrometry (ICP-OES). Modified adsorbents were characterized by SEM, TGA, and FT-IR and compared with native matrixes. SPE of some nonferrous and precious metal ions by biosorbents was studied. Depending on the SPE conditions, it was possible to separate nonferrous and heavy metals from alkali and alkaline earth metals. The proposed adsorbents are effective for preconcentration of nonferrous and heavy metals from natural waters and precious metals from solutions after digestion of geological samples.     

碳酸盐矿石中钨的前处理方法研究

对碳酸盐矿石中钨的熔矿方法进行了研究,分别考察了坩埚、熔剂、双氧水等因素的影响,通过电感耦合等离子体发射光谱法和传统比色法对钨含量的测定结果比较,得出以镍坩埚、氢氧化钠对碳酸盐矿石进行熔矿前处理,钨能较多的存在于溶液中以利于含量的测定。     

电子陶瓷材料元素分析的前处理方法研究

陶瓷材料,由于其耐高温、耐腐蚀、耐磨等性能优异,在各行各业应用相当广泛。但也正是因为它的这些特性,在使用化学方法进行元素分析时,会遇到样品难以消解的问题,导致测试无法进行。文章重点研究电子元件中常用的三氧化二铝、氧化锆类陶瓷材料的消解方法,并介绍使用ICP-OES对消解完全的样品溶液进行元素分析的注意事项。     

电感耦合等离子体发射光谱法测定岩石矿物中铌和钽的方法

文章文研究了用电感耦合等离子体发射光谱法(ICP-OES)测定岩石矿物中的铌和钽的方法。实验考察了不同溶样方法及其对样品的溶解程度,确定了称样量及其溶解的方法,选择了恰当的分析线波长,确定了仪器工作条件,讨论了共存元素的干扰情况。针对不同的干扰采取的方法测定。对方法的准确度及精密度进行了考察。     

直读光谱与电感耦合等离子体发射光谱测定不锈钢中硅、锰、磷、铬、镍的方法比较

通过对比试验,从样品前处理、测定结果等方面对直读光谱法（OES）与电感耦合等离子体发射光谱法（ICP-OES）进行分析。结果表明,两种方法无显著差异,OES的前处理更简单,检测速度更快,但对样品大小、形状要求较高,无法对直径过小的钢铁样品进行检测,而ICP-OES更符合对不同形状钢铁的检测需求。     

电感耦合等离子体发射光谱法测定啤酒中的钙和锶

采用电感耦合等离子体发射光谱(ICP-OES)对啤酒中钙和锶进行测定。通过对硝酸酸度的选择实验、仪器测定的背景扣除及实际样品的测定和加标回收实验,建立了简捷、快速、准确、稳定的ICPOES法测定啤酒中Ca、Sr的分析方法。     

ICP-OES法快速测定白头翁中21种矿物元素

采用微波消解结合电感耦合等离子体发射光谱法(ICP-OES)对白头翁中21种元素含量进行了测定。所采用方法线性关系良好,r≥0.999 0,各元素检出限均低于0.003 6 mg/L,加标回收率为88%~105%,RSD均小于3.6%,具有良好的准确度和精密度。结果表明,白头翁中矿物元素含量丰富、重金属元素含量低于国家最低标准,符合安全用药标准。试验方法简单、快速、可靠、灵敏度高,可同时测定多种元素,满足样品分析要求。该研究结果可为开发利用白头翁药用资源提供基础资料。     

纤维用浆粕中重金属含量的测定

介绍了一种检测浆粕中重金属含量的方法,即通过烧灰法将浆粕灰化,再加入盐酸和醋酸溶解,用等离子体原子发射光谱(ICP-OES)仪检测浆粕中重金属元素的含量。该方法能够准确测定铜、镉、铁、锰、钼、镍等6种重金属元素的含量,具有重复性能好、检出限低、操作简便的优点。