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ammonium ions (Nessler control) and dried at 303 K to constant mass for 2 days. The compounds were identified by the method of elemental analysis (with a Perkin-Elmer CHN 2400 elemental analyzer) and on the base of IR spectra recorded over the range of 4000

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titration. Methods and instruments IR spectra were recorded using a NICOLETT 6700 Spectrometer (4000–400 cm −1 with accuracy of recording 1 cm −1 ) using KBr pellets. Molar conductance was measured on a conductivity meter

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Journal of Thermal Analysis and Calorimetry
Authors: K. Varshney, V. Jain, A. Agrawal, and S. Mojumdar

Abstract  

Pyridine based zirconium(IV) phosphate (PyZrP) and tin(IV) phosphate (PySnP) have been synthesized as new and novel intercalated ion exchangers. These materials have been characterized using X-ray, IR spectra, TG, DTG and DTA studies in addition to their ion exchange capacity, elution, pH titration, concentration and distribution behaviour. The distribution studies towards several metal ions in different media/concentrations have suggested that PyZrP and PySnP are selective for Hg(II) and Pb(II), respectively. As a consequence some binary separations of metal ions involving Hg(II) and Pb(II) ions have been performed on a column of these materials, demonstrating their analytical and environmental potential.

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Abstract  

The paper presents the conditions under which compounds of the commercial herbicides, 2,4-dichlorophenoxyacetic acid (2,4D; C8H6O3Cl2) and 2-(2,4-dichlorophenoxy)-propionic acid (2,4DP; C9H8O3Cl2), with lead(II) and cadmium(II) are formed and the results of the examination of their properties.On the basis of the elemental analysis and Pb and Cd determination, the following molecular formulae for the obtained compounds were proposed: Pb(C8H5O3Cl2)2.H2O, Cd(C8H5O3Cl2)2.2H2O, Pb(C9H7O3Cl2)2·H2O and Cd(C9H7O3Cl2)2·H2O. Water solubility of the synthesized complexes at room temperature was examined. X-ray powder analysis was carried out. The discussion of IR spectra and conductivity data is presented. Thermal decomposition of these compounds in air was studied by TG/MS methods.

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−90 °C with the cooling rate 2 °C/min [ 15 ]. The samples weighed between 10 and 15 mg. All analyses were completed in triplicate. FT-IR spectroscopy IR spectra were registered in the classic range of 4,000–400 cm −1

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-pyrrolo[3,4-c]pyridine-1,3(2H)-dione 1 H NMR spectra were obtained on a 300 MHz Brucker instrument. The samples were prepared by dissolving 5 mg of each form in 600 μl of CDCl 3 . IR spectra (KBr cm −1

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will be observed by comparing the FT-IR spectra (for assigned vibration see Table 2 ) of the initial compound and of the char at 300 and 500 °C (see Fig. 3 ). Table 2 Assigned vibration [ 5 ] for NOOD

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Abstract  

The mixed 2,4'-bipyridine-oxalato complexes of the formulae M(2,4'-bipy)2 C2 O4 2H2 O (M (II)=Mn, Co, Ni, Cu; 2,4'-bipyridine=2,4'-bipy or L ; C2 O2– 4 =ox) have been prepared and characterized. IR data show that the 2,4'-bipy coordinated with these metals(II) via the least hindered (4')N atom; that oxalate group acts as bidentate chelating ligand. Room temperature magnetic moments are normal for the orbital singlet states. The thermal decomposition of these complexes was investigated by TG, DTA and DTG in air. The endothermic or exothermic character of the decomposition of ML2 (ox)2H2 O was discussed.

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Abstract  

Hydrazinium 2,n-pyridinedicarboxylates of general compositions N2H5HA, (N2H5)2AH2O and N2H5HAH2A, where H 2 A=2,n-pyridinedicarboxylic acid (n=3, quinolinic acid;n=4, lutidinic acid; n=5, isocinchomeronic acid and n=6, dipicolinic acid) have been prepared by the neutralisation of aqueous solution of hydrazine hydrate with the respective acids, in stoichiometric ratios. Formation of these hydrazinium derivatives has been confirmed by analytical, IR spectral and thermal studies. Among these, the monohydrazinium salts are anhydrous whereas the dihydrazinium salts are monohydrated. While lutidinic and dipicolinic acids form all the three types of salts, the quinolinic and isocinchomeronic acids do not form N2H5HAH2A and N2H5HA, respectively, except the other two types. Infrared spectra of these salts reveal N-N stretching frequencies of the hydrazinium ion in the region 970-950 cm-1. The simultaneous TG and DTA of these salts show that all of them decompose without clear melting and lose hydrazine endothermically between 200 and 280C, except dihydrazinium isocinchomeronate monohydrate in which half of the hydrazine molecule is lost exothermically, to give pyridinemono- or dicarboxylic acid intermediate which further decomposes exothermically to gaseous products.

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