Comments on “Efficient adsorption of Mn(Ⅱ) by layered double hydroxides intercalated with diethylenetriaminepentaacetic acid and the mechanistic study.J.Environ.Sci.85,56-65”

In the paper entitled"Efficient adsorption of Mn(Ⅱ)by layered double hydroxides intercalated with di ethylenetriaminepentaacetic acid and the mechanistic study"in Journal of Environmental Sciences,volume 85,page 56-65,there were problems with mathematical notation and dimensional errors in the calculation for Giibbs free energy.In Section 2.5:Adsorption isotherms and thermodynamics studies,authors calculated the Gibbs free energy change(△G°)

The Preparation of Perovskite Nano Powder by Sol-gel from DTPA and the Mechanism of Thermal Decomposition

Dy0.8Sr0.2FeO3 nano powder, a synthetic oxide, is made by sol-gel method from metal nitrate and diethylenetriaminepentaacetic acid (DTPA), and the processing parameters are optimized. The process of the preparation, thermal decomposition and the property of the powder are studied by TG-DTA, IR, TEM, and XRD. The diameter of the average grain is about 70 nm. This new technique can be used in the preparation and the studying of na'no materials in the complex oxide system.

Syntheses and Structure of Nine-Coordinate Gd~Ⅲ Complexes,Na[Gd~Ⅲ(edta)(H_2O)_3]·5H_2O and Na_4[Gd~Ⅲ(dtpa)(H_2O)]_2·14H_2O

The crystal and molecular structures of the Na[Gd Ⅲ(edta)(H_2O)_3]·5H_2O (edta=ethylenediaminetetraacetic acid) and Na_4[Gd Ⅲ(dtpa)(H_2O)]_2·14H_2O (dtpa=diethylenetriaminepentaacetic acid) complexes were determined by single-crystal X-ray structure analyses. The crystal of the Na[Gd Ⅲ(edta)(H_2O)_3]·5H_2O belongs to orthorhombic crystal system and Fdd2 space group. The crystal data are as follows: a =1.9424(7)nm,b =3.5496(12)nm,c =1.2125(4)nm,V =8.360(5)nm 3,Z =16,M =612.63,D _c=1.947 g·cm (-3),μ =3.274 mm (-1) and F (000)=4880. The final R and wR values are 0.0295 and 0.0677 for 3102 [ I>2.0σ(I) ] unique reflections,and 0.0328 and 0.0695 for all 8269 reflections,respectively. The [Gd Ⅲ(edta)(H_2O)_3]-complex anion has a nine-coordinate pseudo-monocapped square antiprismatic structure in which the nine coordinate atoms,two N and seven O are from one edta ligand and three coordinate water molecules. The crystal of the Na_4[Gd Ⅲ(dtpa)(H_2O)]_2·14H_2O belongs to monoclinic crystal system and P2(1)/n space group. The crystal data are as follows: a =1.4894(6)nm,b =1.7987(7)nm, c =1.9600(7)nm,β =99.496(7),V =5.179(3)nm3,Z=4,M =1471.44,D _c=1.841 g·cm (-3),μ =2.676 mm (-1) and F (000)=2872. The final R and wR are 0.0435 and 0.0979 for 8929 [ I>2.0σ(I) ] unique reflections,and 0.0820 and 0.1167 for all 20717 reflections,respectively. The total complex moleculue is composed of two close parts in structure. The [Gd Ⅲ(dtpa)(H_2O)] (2-) complex anion in the every part has a nine-coordinate structure with distorted monocapped square antiprismatic prism,in which the dtpa coordinates with central Gd Ⅲ ion acting as a octadentate ligand with three N atoms and five O atoms,and one water as the ninth ligand directly coordinates with central Gd Ⅲ ion.

Synthesis and Crystal Structure of a Heteronuclear Complex［MnSc（DTPA）（H_2O）_2］·2H_2O

The title complex, [MnSc (DTPA) (H2O)2]·2H2O (DTPA is diethylenetriaminepentaacetic acid). has been synthesized in aqueous solution. Its crystal structure has been determined by four-circle X-ray diffractometer. The crystal is monoclinic with space group P21/n. The cell parameters are as follows:α=0.7886 (3) nm, b=1.5094 (5) nm. c=1. 8162(6) nm; β=100. 32(2)°, V= 2. 121 (2) nm3 , Z= 4 , Dc =1. 75 g/cm3. In the crystal,Sc3+ ion is coordinated by five oxygen atoms and three nitrogen atoms of DTPA with coordination number eight. taking a trigondodecahedron arrangement. Mn2+ ion is coordinated by four oxygen atoms from different DTPA and two oxygen atoms from H2O molecules with coordination number six, forming an octahedron. Each Sc(DTPA) is further connected with Mn2+ ions through four carboxyl groups of DPTA serving as bridges to form a three dimensional network.

Dopamine-containing gadolinium complex as magnetic resonance imaging contrast agent

Gadolinium diethylenetriamine-pentaacetic bisdopamide （Gd-DTPA-2DA） was synthesized by the incorporation of dopamine to diethylenetriaminepentaacetic acid （DTPA） and further reaction with gadolinium chloride. In vitro and in vivo properties were also evaluated. Gadolinium complex Gd-DTPA-2DA possessed higher relaxation effectiveness and less cytotoxicity to HeLa cells than that of Gd-DTPA. Moreover, Gd-DTPA-2DA greatly enhanced the contrast of MR images of the brains, provided prolonged intravascular duration, and pro- duced highly contrasted visualization of the brain.