ICP—AES卡尔曼滤波同时测定铁基体中26种痕量元素

本文利用电感耦合等离子体原子发射光谱（ＩＣＰ－ＡＥＳ）多色仪的扫描功能，用Ｃ语言编制了Ｋａｌｍａｎ滤波程度软件包，用该软件包对铁基体中２６种痕量元素进行了回收率试验，并对标准碳素钢样中１３种痕量元素进行了测定，结果表明Ｋａｌｍａｎ滤波完全适用于复杂谱线基体中的多种元素同时分析。     

Thermal properties of rare earth elements complexes with 1,3,5-benzenetricarboxylic acid

Summary Rare earth elements 1,3,5-benzenetricarboxylates were prepared as solids of the general formula Ln(C₉H₃O₆)·nH₂O, where n=6 for La-Dy and n=4 for Ho-Lu,Y. Their solubilities in water at 293 K are of the order 10^-4-10^-6 mol dm^-3. The IR spectra of the complexes indicate that the carboxylate groups are bridging and bidentate chelates. Hydrated 1,3,5-benzenetricarboxylates lose water molecules during heating in one step (La-Tb), two steps (Y, Ho-Tm) or three steps (Dy, Yb, Lu). The anhydrous complexes are stable up to 573-742 K and decompose to oxides (Ce-Lu) at higher temperatures.     

端视ICP－AES系统分析性能研究──Ⅰ．在稀土分析中的应用

本工作通过比较端视与侧视ＩＣＰ的分析性能，研究了端视ＩＣＰ系统对稀土元素的分析特性。高频发生器输出功率与载气流量对端视与侧视ＩＣＰ激发特性的影响没有明显差异，取光方式的不同是二者分析性能差异的根本原因。端视ＩＣＰ由于取光时避开了产生连续背景的环形热区和截取了整个中心通道的光谱，其背景减小，谱线强度增强，获得较好的测定下限。对１４种稀土元素测定下限的比较表明：端视ＩＣＰ比铡视ＩＣＰ下降１０－３０倍。     

Simultaneous determination of hydride (Se) and non-hydride-forming (Ca,Mg, K,P, S and Zn) elements in various beverages (beer,coffee, and milk), with minimum sample preparation,by ICP–AES and use of a dual-mode sample-introduction system

A method has been developed enabling direct analysis (i.e. after dilution only) of beer, instant coffee, milk, and milk powder by ICP–AES. Analysis of the beverages after dilution with a low concentration of HNO₃ was used for accurate determination of essential minor and trace elements (Ca, Mg, K, P, S, and Zn). Selenium, introduced as the hydride, was determined simultaneously with the other non-hydride-forming elements using the commercial multi-mode sample-introduction system (MSIS). To obtain accurate results, however, some simple pre-treatment was needed. Analysis was also performed after microwave-assisted decomposition of the samples. Three different modes of sample-preparation, i.e. dilution only, partial decomposition (aqua regia treatment), and complete decomposition were compared. The results obtained by use of the three different sample-preparation methods were in very good agreement. Results from analysis of certified reference material (SRM 1459 non-fat milk powder) also verified the accuracy of the methods. The limit of detection obtained for Se using dual-mode sample introduction was 0.5 ng mL^–1, which corresponds to approximately 2 ng g^–1 in beer and approximately 4 ng g^–1 in coffee and milk when using the recommended procedure.     

用原子捕获技术提高火焰原子吸收光谱法的灵敏度

采用简易的石英原子捕获器，使Ｃｕ，Ａｇ，Ａｕ，Ｚｎ，Ｃｄ，Ｐｂ，Ｓｂ，Ｂｉ等易挥发元素在空气－乙炔火焰原子吸收光谱法中的灵敏度提高了３～５倍，并有较好的精密度，相对标准偏差在１％左右，方法中用此技术测定了标准物质中Ｐｂ、Ｃｄ的含量，获得了满意的结果，它较之石墨炉原子吸收光地具有快速，简便的特点，具有较大的实用价值。     

Procedure for dissolving wolframite in order to determine trace elements by atomic absorption spectrometry

An analytical procedure for dissolving wolframite in order to determine trace elements by atomic absorption is reported. After decomposition of the mineral by alkaline fusion, the cooled flux is dissolved by heating with aqua regia. The finely crystalline precipitate of tungstite, which forms on standing, is filtered and dissolved by heating with aqua regia. Tungstite forms again in the latter solution and the filtration and solubilization are repeated until the solution contains negligible amounts of trace elements. Following this procedure, trace elements in 35 samples of natural wolframite have been dissolved and the solutions obtained have been analyzed by atomic absorption spectrometry for Fe, Mn, Cu, Zn, Pb, Co, Ni and Cd.     

高血压类风湿症疗效与锌,钙关系初探

以临床典型病案为例，探讨了中医中药传统理论和现代微量元素研究的关系，重点讨论了向量元素锌、宏量元素钙与高血压、风湿症的病因病机和治疗关系。     

拓扑指数法研究稀土显色剂结构与铈显色反应对比度的关系

计算了４３种不对称变色酸双偶氮膦酸型显色剂的Ａｍ拓扑指数，并将其与结构选择性因子相结合，用于偶氮类显色剂结构与铈显色反应对比度的相关性研究，讨论了显色剂结构对拓扑指数有译比度的影响。     

1,2‐Dithioquadratato‐ und 1,2‐Dithiooxalatoindate(III)

Indium(III) chloride forms in water with potassium 1,2‐dithiooxalate (dto) and potassium 1,2‐dithiosquarate (dtsq) stable coordination compounds. Due to the higher bridging ability of the 1,2‐dithiooxalate ligand in all cases only thiooxalate bridged binuclear complexes were found. From 1,2‐dithioquadratate with an identical donor atom set mononuclear trischelates could be isolated. Five crystalline complexes, (BzlMe₃N)₄[(dto)₂In(dto)In(dto)₂] ( 1 ), (BzlPh₃P)₄[(dto)₂In(dto)In(dto)₂] ( 2 ), (BzlMe₃N)₃[In(dtsq)₃] ( 3 ), (Bu₄N)₃[In(dtsq)₃] ( 4 ) and (Ph₄P)[In(dtsq)₂(DMF)₂] ( 5 ), have been isolated and characterized by X‐ray analyses. Due to the type of the complex and the cations involved these compounds crystallize in different space groups with the following parameters: 1 , monoclinic in P2₁/c with a = 14.4035(5) Å, b = 10.8141(5) Å, c = 23.3698(9) Å, β = 124.664(2)°, and Z = 2; 2 , triclinic in P with a = 11.3872(7) Å, b = 13.6669(9) Å, c = 17.4296(10) Å, α = 88.883(5)°, β = 96.763(1)°, γ = 74.587(5)°, and Z = 1; 3 , hexagonal in R3 with a = 20.6501(16) Å, b = 20.6501(16) Å, c = 19.0706(13) Å and Z = 6; 4 , monoclinic in P2₁/c with a = 22.7650(15) Å, b = 20.4656(10) Å, c = 14.4770(9) Å, β = 101.095(5)°, and Z = 4; 5 , triclinic in P with a = 9.2227(6) Å, b = 15.3876(9) Å, c = 15.5298(9) Å, α = 110.526(1)°, β = 100.138(1)°, γ = 101.003(1)°, and Z = 2.     

ICP-AES determination of trace elements after preconcentrated with p-dimethylaminobenzaldehyde-modified nanometer SiO2 from sample solution

A new method that utilizes p-dimethylaminobenzaldehyde-modified nanometer SiO₂ (SiO₂-p-DMABD) as a solid phase extractant has been developed for simultaneous preconcentration of trace Cr(III), Cu(II), Fe(III) and Pb(II) prior to the measurement by inductively coupled plasma atomic emission spectrometry (ICP-AES). The preconcentration conditions of analytes were investigated, including the pH value, the shaking time, the mass of sorbent, the sample flow rate and volume, the elution condition and the interfering ions. The adsorption capacity of nanometer SiO₂-p-DMABD was found to be (mg g^− 1) Cr(III): 6.2, Cu(II): 18.6, Fe(III): 4.7 and Pb(II): 6.0 at pH 4. The adsorbed metals were quantitatively eluted with 4 mL of 1.0 mol L^− 1 HCl. According to the definition of IUPAC, the detection limits (3σ) of this method for Cr(III), Cu(II), Fe(III) and Pb(II) were 0.79, 1.27, 0.40 and 1.79 ng mL^− 1, respectively. The proposed method achieved satisfied results when it was applied to the determination of trace Cr(III), Cu(II), Fe(III) and Pb(II) in biological and water samples.