A closed-vessel microwave digestion method is described for the rapid dissolution of environmental samples such as foods, soils and sediments. Depending on the sample type, 0.1-0.2 g sample was decomposed with HNO3/H2...A closed-vessel microwave digestion method is described for the rapid dissolution of environmental samples such as foods, soils and sediments. Depending on the sample type, 0.1-0.2 g sample was decomposed with HNO3/H2O2 or HNO3 / H2O2/HF acid mixture in a PTFE digestion vessel by using microwave heating for 2-3 min at 500W of microwave power. The solution, or to which 0.5 g of boric acid was added, was diluted to 25-50 ml and directly determined by sequential ICP-AES. The accuracy of the procedure was validated by the analysis of six standard reference materials for 10 elements. Ail results were in a good agreements with the certified values.展开更多
On-line dissolution of solid metal sample can be carried out by electrolysis under the control of flow injection analyzer(FIA),and the dissolved sample can be transferred to atomic spectrometer for the direct analysis...On-line dissolution of solid metal sample can be carried out by electrolysis under the control of flow injection analyzer(FIA),and the dissolved sample can be transferred to atomic spectrometer for the direct analysis.The hyphenated technique of FIA on-line electrolytic dissolution of alloy and atomic absorption spectrometer(AAS)detection is developed.The research is focused on the effects of electrolyte composition and electrolysis parameters on the sample dissolving,as well as the quantitative analysis of Cu in Al alloy samples.展开更多
In this paper, a new MPT(microwave plasma torch) device has been used as a atomizer for atomic fluorescence spectrometry. Spme elements, such as Zn, Cd, Hg, Pb, As, Co, Mg, Cu, Ag, Mn, Fe have been investigated in det...In this paper, a new MPT(microwave plasma torch) device has been used as a atomizer for atomic fluorescence spectrometry. Spme elements, such as Zn, Cd, Hg, Pb, As, Co, Mg, Cu, Ag, Mn, Fe have been investigated in detail.展开更多
Atmospheric pressure plasmas are not only powerful sources for excitation but also very good atomizers. In the early developing stage, the inductively coupled plasma (ICP) was investigated as an atomizer for atomic ab...Atmospheric pressure plasmas are not only powerful sources for excitation but also very good atomizers. In the early developing stage, the inductively coupled plasma (ICP) was investigated as an atomizer for atomic absorption spectrometry (AAS). A multiple pass system,a T-shaped plasma cell,and a long-path torch was used to increase the absorption path length. But all these ICP-AAS systems gave low sensitivities for most展开更多
The material composition of geological samples is very complicated. Generally, the method for accurately determining trace elements in geological samples needs to digest the solid samples into liquid state, which is c...The material composition of geological samples is very complicated. Generally, the method for accurately determining trace elements in geological samples needs to digest the solid samples into liquid state, which is convenient for inductively coupled plasma mass spectrometry. The previous digestion method takes a long time and the operation process is complicated. The Ultra CLAVE microwave digestion instrument was used to digest the geological samples. The types and dosages of the acid used for digestion and the optimal conditions for instrumental testing were published. The results show that this method has short processing time, small data error, safer operation and good digestion effect. This method is suitable for geological sample analysis.展开更多
安全处置的铬渣常出现“返黄”现象,这与未溶解的含六价铬(Cr(Ⅵ))矿物再次释放Cr(Ⅵ)有关,因此在修复过程中,彻底溶解不稳定的含Cr(Ⅵ)矿物,使其充分释放Cr(Ⅵ)是实现铬渣长效稳定的关键。该研究利用微波(MW)快速溶解铬渣中Cr(Ⅵ)矿物...安全处置的铬渣常出现“返黄”现象,这与未溶解的含六价铬(Cr(Ⅵ))矿物再次释放Cr(Ⅵ)有关,因此在修复过程中,彻底溶解不稳定的含Cr(Ⅵ)矿物,使其充分释放Cr(Ⅵ)是实现铬渣长效稳定的关键。该研究利用微波(MW)快速溶解铬渣中Cr(Ⅵ)矿物——钙钒石,再耦合硫酸亚铁(FeSO_(4))实现了铬渣的高效稳定。MW辐照显著降低了钙矾石溶解的表观活化能(35.8 k J/mol),促进钙矾石快速溶解释放Cr(Ⅵ)。而FeSO_(4)水解酸化产生的硫酸(H2SO_(4))在MW场下进一步促进了含Cr(Ⅵ)矿物水滑石的溶解,实现了铬渣中Cr(Ⅵ)矿物的完全溶解。同时,MW显著提升了FeSO_(4)对Cr(Ⅵ)的还原效率,在低功率MW(462 W)耦合低剂量FeSO_(4)(w=21.5%)处理下,Cr(Ⅵ)的还原率达到100%。更为重要的是,MW促进了生成的三价铬(Cr(Ⅲ))固定在Cr(Ⅲ)矿物(Fe O·Cr_(2)O_(3)和Cr_(2)O_(3))晶格中,1年后未出现“返黄”,实现了铬渣的长效稳定。该研究为MW耦合FeSO_(4)在铬渣稳定化处理领域的应用提供了数据支持和理论基础。展开更多
文摘A closed-vessel microwave digestion method is described for the rapid dissolution of environmental samples such as foods, soils and sediments. Depending on the sample type, 0.1-0.2 g sample was decomposed with HNO3/H2O2 or HNO3 / H2O2/HF acid mixture in a PTFE digestion vessel by using microwave heating for 2-3 min at 500W of microwave power. The solution, or to which 0.5 g of boric acid was added, was diluted to 25-50 ml and directly determined by sequential ICP-AES. The accuracy of the procedure was validated by the analysis of six standard reference materials for 10 elements. Ail results were in a good agreements with the certified values.
文摘On-line dissolution of solid metal sample can be carried out by electrolysis under the control of flow injection analyzer(FIA),and the dissolved sample can be transferred to atomic spectrometer for the direct analysis.The hyphenated technique of FIA on-line electrolytic dissolution of alloy and atomic absorption spectrometer(AAS)detection is developed.The research is focused on the effects of electrolyte composition and electrolysis parameters on the sample dissolving,as well as the quantitative analysis of Cu in Al alloy samples.
文摘In this paper, a new MPT(microwave plasma torch) device has been used as a atomizer for atomic fluorescence spectrometry. Spme elements, such as Zn, Cd, Hg, Pb, As, Co, Mg, Cu, Ag, Mn, Fe have been investigated in detail.
文摘Atmospheric pressure plasmas are not only powerful sources for excitation but also very good atomizers. In the early developing stage, the inductively coupled plasma (ICP) was investigated as an atomizer for atomic absorption spectrometry (AAS). A multiple pass system,a T-shaped plasma cell,and a long-path torch was used to increase the absorption path length. But all these ICP-AAS systems gave low sensitivities for most
文摘The material composition of geological samples is very complicated. Generally, the method for accurately determining trace elements in geological samples needs to digest the solid samples into liquid state, which is convenient for inductively coupled plasma mass spectrometry. The previous digestion method takes a long time and the operation process is complicated. The Ultra CLAVE microwave digestion instrument was used to digest the geological samples. The types and dosages of the acid used for digestion and the optimal conditions for instrumental testing were published. The results show that this method has short processing time, small data error, safer operation and good digestion effect. This method is suitable for geological sample analysis.
文摘安全处置的铬渣常出现“返黄”现象,这与未溶解的含六价铬(Cr(Ⅵ))矿物再次释放Cr(Ⅵ)有关,因此在修复过程中,彻底溶解不稳定的含Cr(Ⅵ)矿物,使其充分释放Cr(Ⅵ)是实现铬渣长效稳定的关键。该研究利用微波(MW)快速溶解铬渣中Cr(Ⅵ)矿物——钙钒石,再耦合硫酸亚铁(FeSO_(4))实现了铬渣的高效稳定。MW辐照显著降低了钙矾石溶解的表观活化能(35.8 k J/mol),促进钙矾石快速溶解释放Cr(Ⅵ)。而FeSO_(4)水解酸化产生的硫酸(H2SO_(4))在MW场下进一步促进了含Cr(Ⅵ)矿物水滑石的溶解,实现了铬渣中Cr(Ⅵ)矿物的完全溶解。同时,MW显著提升了FeSO_(4)对Cr(Ⅵ)的还原效率,在低功率MW(462 W)耦合低剂量FeSO_(4)(w=21.5%)处理下,Cr(Ⅵ)的还原率达到100%。更为重要的是,MW促进了生成的三价铬(Cr(Ⅲ))固定在Cr(Ⅲ)矿物(Fe O·Cr_(2)O_(3)和Cr_(2)O_(3))晶格中,1年后未出现“返黄”,实现了铬渣的长效稳定。该研究为MW耦合FeSO_(4)在铬渣稳定化处理领域的应用提供了数据支持和理论基础。
文摘流程工业颗粒物成分的在线检测具有低延时、安全可靠及低成本等要求,目前没有适合的技术手段.微波等离子炬(Microwave plasma torch,MPT)原子发射光谱法具有直接进样、成本低及装置安全可靠等优点,有潜力成为工业在线检测的重要手段.本文基于MPT装置对水泥样品进行直接进样分析,并针对工业应用场景中标准样品受限的问题,采用单样本定标技术(Single sample calibration,SSC)进行定量分析.SSC法中的线性假设容易受到等离子体参数波动的影响,导致精度下降.为此,提出了一种基于参数标准化的SSC算法PS-SSC(SSC based on parameter standardization),通过激发温度和电子数密度对谱线强度进行修正以提高SSC的定量精度.为了评估MPT和PS-SSC方法联用在水泥成分快速分析中的有效性,将GSB 08-2985-2013标准水泥粉末气溶胶直接引入MPT中进行定量分析,并将PS-SSC与现有定量方法进行比较.与传统SSC方法相比,PS-SSC方法的决定系数R2由‒0.81~0.81提高到0.39~0.88,平均相对误差由4.39%~10.33%提高到1.55%~5.83%,平均相对标准偏差由2.89%~9.40%提高到2.28%~6.50%,展现了该方法在工业在线成分检测中的应用潜力.
