Decomposition of vegetables for determination of Zn,Cd, Pb and Cu by stripping voltammetry

A simple and accurate digestion method using nitric acid, perchloric acid and hydrogen peroxide has been developed for use in trace analysis for heavy metals in vegetables by differential pulse anodic stripping voltammetry. The recovery of the metals from the samples is lower if the hydrogen peroxide is omitted from the digestion mixture. Standard reference materials have been analysed satisfactorily by this method.     

微量元素与高血压Ⅰ.高血压病人的元素含量异常

高血压是脑卒中和冠心病的主要危险因素，我国现有1．2亿人正受到高血压的威胁。大多数高血压是可以防治的。膳食防治高血压的本质是维持元素平衡或纠正破坏了的元素平衡关系。本文简述了我国高血压流行情况、不同血压水平的心脑血管病发病危险、血压与微量元素的相关关系、高血压患者的元素含量异常，以及高血压的元素食疗防治。附1图、33表、44篇参考文献。     

新的脉冲进样AAS法测定“麻杏石甘汤”中的微量金属元素

本文研制了一种新的脉冲进样装置，用于火娄原子吸收分光光度法测定中药煎剂中的Ｃａ，Ｍｇ，Ｆｅ，Ｍｎ，Ｚｎ五种金属元素含量，实验表明，利用此种装置可以同时获得两种进样方式的分析结果，线性范围比常规法宽两倍，耗样量，精密度及分析速度均优于常规法。     

The impact of flow injection on modern chemical analysis: has it fulfilled our expectations? And where are we going?

Presenting a condensation of the opening lecture of the 12th ICFIA conference, this communication presents a view of the impact that flow injection analysis (FIA) has had on modern analytical chemistry, evaluated both within the academic community and outside it, i.e. in “industry”. The ensuing developments of FIA, encompassing sequential injection analysis (SIA) and bead injection lab-on-valve (BI-LOV), are described and their individual features discussed. Finally, some recent results of the activities from the author’s own research group are briefly mentioned.     

Metallocycle synthesis accelerated by high pressure

Reaction of cis-[FeH₂(dmpe)₂](1) with diphenylbutadiyne results in an insertion into both of the iron-hydride bonds to form an iron metallocycle. Spectroscopic and crystallographic data of [Fe(PhHCC₂CHPh)(dmpe)₂] (3) show 1,4-diphenylbutatriene is symmetrically bound to the metal via the central double bond. The reaction to form the metallocyclic complex is greatly accelerated by application of external pressure. A 41% yield of (3) is isolated after two days at atmospheric pressure or after approximately 75 min at 800MPa.     

过敏性哮喘患者血清中10种必需微量元素水平的研究

３４例过敏性哮喘患者血清中铁，锌、铜，锰硒铬，钴镍，钡，钼的含量水平与对照组比较，揭示：（１）铁，铜，铬的含量升高；（２）硒，镍，钴、钒的钼的含量降低；（３）锌和锰的含量差异无显著性，Ｐ〉０．０５。     

梅州农村饮用水重金属元素监测与分析

对梅州农村饮用水中的重金属元素进行了监测和分析，选择Fe，Mn，Zn，Cu，Ag，Pb，Cd七种元素为检测指标。从实验结果来看，Cu，Ag，Cd含量低，未超标；Fe，Mn，Zn，Pb有超标现象：按其危害程度，Pb，Mn的超标是急需解决的问题。     

CoSm(SeO3)2Cl,CuGd(SeO3)2Cl,MnSm(SeO3)2Cl,CuGd2(SeO3)4 und CuSm2(SeO3)4: Übergangsmetallhaltige Selenite von Samarium und Gadolinum

CoSm(SeO₃)₂Cl, CuGd(SeO₃)₂Cl, MnSm(SeO₃)₂Cl, CuGd₂(SeO₃)₄ and CuSm₂(SeO₃)₄: Transition Metal containing Selenites of Samarium and Gadolinum The reaction of CoCl₂, Sm₂O₃, and SeO₂ in evacuated silica ampoules lead to blue single crystals of CoSm(SeO₃)₂Cl (triclinic, , Z = 4, a = 712.3(1), b = 889.5(2), c = 1216.2(2) pm, α = 72.25(1)°, β = 71.27(1)°, γ = 72.08(1)°, R_all = 0.0586). If MnCl₂ is used in the reaction light pink single crystals of MnSm(SeO₃)₂Cl (triclinic, , Z = 2, a = 700.8(2), b = 724.1(2), c = 803.4(2) pm, α = 86.90(3)°, β = 71.57(3)°, γ = 64.33(3)°, R_all = 0.0875) are obtained. Green single crystals of CuGd₂(SeO₃)₂Cl (triclinic, , Z = 4, a = 704.3(4), b = 909.6(4), c = 1201.0(7) pm, α = 70.84(4)°, β = 73.01(4)°, γ = 70.69(4)°, R_all = 0.0450) form analogously in the reaction of CuCl₂ and Gd₂O₃ with SeO₂. CoSm(SeO₃)₂Cl contains [CoO₄Cl₂] octahedra, which are connected via one edge and one vertex to infinite chains. The Mn²⁺ ions in MnSm(SeO₃)₂Cl are also octahedrally coordinated by four oxygen and two chlorine ligands. The linkage of the polyhedra to chains occurs exclusively via edges. Both, the cobalt and the manganese compound show the Sm³⁺ ions in eight and ninefold coordination of oxygen atoms and chloride ions. In CuGd(SeO₃)₂Cl the Cu²⁺ ions are coordinated by three oxygen atoms and one Cl^— ion in a distorted square planar manner. One further Cl^— and one further oxygen ligand complete the [CuO₃Cl] units yielding significantly elongated octahedra. The latter are again connected to chains via two common edges. For the Gd³⁺ ions coordination numbers of ?8 + 1”? and nine were found. Single crystals of the deep blue selenites CuM₂(SeO₃)₄ (M = Sm/Gd, monoclinic, P2₁/c, a = 1050.4(3)/1051.0(2), b = 696.6(2)/693.5(1), c = 822.5(2)/818.5(2) pm, β = 110.48(2)°/110.53(2)°, R_all = 0.0341/0.0531) can be obtained from reactions of the oxides Sm₂O₃ and Gd₂O₃, respectively, with CuO and SeO₂. The crystal structure contains square planar [CuO₄] groups and irregular [MO₉] polyhedra.     

Spectrafluorimetric method for the rapid screening of toxic heavy metals in water samples

A fast and inexpensive sensitive screening test for recognising potential wastewater contamination by the presence of highly toxic heavy metals is described. The test is based on the reaction of the toxic heavy metals Hg(II), Cd(II), Pb(II) and Ag(I) with 6-mercaptopurine (6-MP) to produce highly fluorescent complexes.Optimum experimental conditions include a buffer of pH 7.2 (0.1 M citric acid/0.2 M Na₂HPO₄), a chelating reagent concentration of 6×10⁻⁴ M and the addition of 10⁻⁴ M of o-phenanthroline. The fluorescence emitted by the complexes was measured at 380 and 540 nm for excitation and emission wavelengths, respectively.Detection limits of 4, 3, 6 and 3 μg l⁻¹ were achieved for Hg, Cd, Pb and Ag. Relative standard deviation (R.S.D.) were between ±2 and ±6% of the fluorescence signals for five identical samples. Potential interference effects from other heavy metals (Zn, Mn, Co, Fe, Ni and Cu), which could affect the response of the proposed screening test was investigated. Results showed that none of these metals give rise to noticeable fluorescence signals under the above described experimental conditions.Finally, the capability of the proposed heavy metal screening test for the analysis of contaminated water samples is discussed.     

Effect of HF addition on the microwave-assisted acid-digestion for the determination of metals in coal by inductively coupled plasma-atomic emission spectrometry

The microwave-assisted acid-digestion for the determination of metals in coal by ICP-AES was investigated, especially focusing on the necessity of adding HF. By testing five certified reference materials, BCR-180, BCR-040, NIST-1632b, NIST-1632c, and SARM-20, it was found that the two-stage digestion without HF (HNO₃ + H₂O₂ was used) was very effective for the pretreatment of ICP-AES measurement. Both major metals (Al, Ca, Fe, and Mg) and minor or trace metals (Co, Cr, Cu, Mn, Ni, Pb, and Zn) in coal gave good recoveries for their certified or reference values. The possibility of ‘HF-memory effect’ was cancelled by the use of a set of vessels which had been never contacted with HF. Twenty-four Japanese standard coals (SS coals) were analyzed by the present method, and the concentrations of major metals measured by the present method provided very high accordance with those from the authentic JIS (Japanese Industrial Standard) method.