819 resultados para EDTA


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We report a one-pot preparation method for a series of novel shaped gold microcrystals by simply mixing HAuCl4 with disodium salt of ethylenediaminetetraacetic acid (Na(2)EDTA). Under the different reaction temperatures, spinous structures, multipod microspheres, and rough surfaced microspheres were obtained. These microcrystals exhibit high surface-enhanced Raman scattering (SERS) activity.

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In this paper we describe the moleculare and crystal structures of the Na-3[Hg( II )(edta)Cl] . 6H(2)O (edta=ethylenediamine-N,N,N',N'-tetraacetate). The crystal data are as follows: orthorhombic, a=8. 083 (2) Angstrom , b=13. 870(3) Angstrom , c=38. 617(5) Angstrom , v=4329. 4 (13) Angstrom(3) , Z=8, Dc= 1. 798 g . cm(-3), mu=5. 564 mm(-1), P(000)=2280, R=0. 0317 and R-w=0. 0731 for 3883 unique reflections. In complex, the complex anion [Hg ( II ) (edta)Cl](3-) has a seven-coordination structure like a mono-capped trigonal-prism (C-2v-MTP) in which the edta(4-) acts as a hexadentate ligand with four O atoms and two N atoms and a Cl- caps a quadrilateral face as a seventh ligand. It can be known that the Hg2+ which has a d(10) electronic structure can form a high-coordinate compound with a hexadentate ligand (edta) because it has a big ionic radius.

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各种各样的氨基多羧酸类配合物多年来一直是化学家们较为感兴趣的研究课题之一[1~4]。特别是近年来,氨基多羧酸类配体作为一些有毒重金属的排泄剂[5]和与一些放射性金属离子形成配合物后作为核医学的显影剂[6]等方面得到了广泛的应用。金属Hg是有毒的,一般…

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水培实验研究表明,100mg/L的Cu^2+和0.5mmol/L的EDTA对狭叶香蒲(Typha angustifolia L.)的生长起到抑制作用。同时0.5mmol/L的EDTA能够促进狭叶香蒲吸收水中的Cu^2+,并促进Cu^2+从须根向地上部分转移,茎和叶中积累的Cu^2+浓度为1233.8mg/kg和632.3mg/kgDW(干重),Cu^2+从须根转移到茎部分的转移系教TFs从0.95上升到2.15;从须根转移到叶部分的转移系教从0.48上升到1.10.

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Nanocrystalline ZrO2:Eu was synthesized by complexing sol-gel method. The effects of heat treatment on structure, grain size and luminescence properties of ZrO2:Eu were studied with X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and photoluminescence measurements. The dependence between the fluorescence emission and the crystalline structure is discussed. (c) 2004 Elsevier B.V. All rights reserved.

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p.133-137