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complexes in the lanthanide series. Experimental Preparation of Ln 2 (C 12 H 6 O 4 ) 3 · n H 2 O Due to insolubility of 2,3-naphthalenedicarboxylic acid in water, we prepared its ammonium salt (pH = 5.8) to

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chromatograph with a thermal conductivity detector (TCD) and a flame ionization detector (FID). A TDX01 column was used for the separation of O 2 , CO, CH 4 and CO 2 , and a [DNBM+ODPN] column was used for the analysis of CH 4 , C 2 H 4 , C 2 H 6 , C 3 H 6 and

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Journal of Thermal Analysis and Calorimetry
Authors:
Li-Fang Song
,
Cheng-Li Jiao
,
Chun-Hong Jiang
,
Jian Zhang
,
Li-Xian Sun
,
Fen Xu
,
Qing-Zhu Jiao
,
Yong-Heng Xing
,
F. L. Huang
,
Yong Du
,
Zhong Cao
,
Fen Li
, and
Jijun Zhao

900489g . 12. Dinca , M , Long , JR 2005 Strong H-2 binding and selective gas adsorption within the microporous coordination solid Mg-3(O2C–C10H6–CO2)(3) . J Am Chem Soc 127 : 9376

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8-hydroxyquinoline (oxine) and uranyl acetate react in the solid state in 1∶3 stoichiometry to give UO2(C9H6NO)2·C9H6NOH. This reaction is diffusion controlled with an activation energy of 44.4 kJ mol−1. The reaction occurs by the surface migration of 8-hydroxyquinoline, which penetrates the product lattice to react with uranyl acetate. The isothermal decomposition of the solution phase product UO2Q2·HQ (Q=C9H6NO) obeys the Prout-Tompkins equation with an energy of activation of 53.3 kJ mol−1.

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-source precursor[Pb(H 2 O) 3 ] 2 [Ti 2 (O 2 ) 2 O(NC 6 H 6 O 6 ) 2 ]·4H 2 O ( 1 ) The flowchart for synthesis of compound 1 and PbTiO 3 material is summarized in Scheme 1 . To the suspension of H 3 nta (9.57 g, 50 mmol) in 50 mL of deionized water was

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Abstract  

Solubility and pH precipitation studies were carried out to obtain the binuclear complex {[TiO(C9H6NO)2][Sn(C9H6NO)2]} involving 8-hydroxyquinoline as chelating agent. The compound, the individual mononuclear complexes and their physical mixture were evaluated by means of techniques such as TG, DTA, elemental analysis, X-ray diffraction, IR spectroscopy. The properties of the original compounds and also the thermoanalytical conditions exerted a great influence on the degree of crystallinity and on the crystalline phase of the mixed oxide obtained as final product of the thermal decomposition.

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Abstract  

The [MoOC1(dppe)2]Cl complex [dppe=(C6H6)2P(CH2)2 P(C6H5)2] was successfully examined in a process of reduction of molecular nitrogen in -radiation field. Yields of ammonia produced in this process were measured as a function of the Mo(IV) complex concentration and dose.

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Abstract  

In order to obtain cobalt oxides nanoparticles we have used the thermal decomposition of some carboxylate type precursors. These precursors were obtained by the redox reaction between cobalt nitrate and ethylene glycol, either bulk or dispersed in silica matrix. The redox reaction takes place by heating the Co(NO3)2·6H2O-C2H6O2 solution or the Si(OC2H5)4-Co(NO3)2·6H2O-C2H6O2 gels. Thermal analysis of the Co(NO3)2·6H2O-C2H6O2 solution and Si(OC2H5)-Co(NO3)2·6H2O-C2H6O2 gels allowed us to establish the optimal value for the synthesis temperature of the carboxylate precursors. By fast heating of the solution Co(NO3)2·6H2O-C2H6O2, the redox reaction is immediately followed by the decomposition of the precursor, which represents an autocombustion process. The product of this combustion contains CoO as unique phase. We have obtained a mixture of CoO and Co3O4 by annealing the synthesized carboxylate compounds for 2 h at 400°C. With longer annealing time (6 h), we have obtained Co3O4 as unique phase. The XRD study of the crystalline phases resulted by thermal decomposition of the precursors embedded in silica matrix, showed that the formation of Co2SiO4 and Co3O4, as unique phases, depends on the thermal treatment.

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Abstract  

The complexes of 4-chloro-2-methoxybenzoic acid anion with Mn2+, Co2+, Ni2+, Cu2+ and Zn2+ were obtained as polycrystalline solids with general formula M(C8H6ClO3)2 nH2O and colours typical for M(II) ions (Mn – slightly pink, Co – pink, Ni – slightly green, Cu – turquoise and Zn – white). The results of elemental, thermal and spectral analyses suggest that compounds of Mn(II), Cu(II) and Zn(II) are tetrahydrates whereas those of Co(II) and Ni(II) are pentahydrates. The carboxylate groups in these complexes are monodentate. The hydrates of 4-chloro-2-methoxybenzoates of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) heated in air to 1273 K are dehydrated in one step in the range of 323–411 K and form anhydrous salts which next in the range of 433–1212 K are decomposed to the following oxides: Mn3O4, CoO, NiO and ZnO. The final products of decomposition of Cu(II) complex are CuO and Cu. The solubility value in water at 293 K for all complexes is in the order of 10–3 mol dm–3. The plots of χM vs. temperature of 4-chloro-2-methoxybenzoates of Mn(II), Co(II), Ni(II) and Cu(II) follow the Curie–Weiss law. The magnetic moment values of Mn2+, Co2+, Ni2+ and Cu2+ ions in these complexes were determined in the range of 76−303 K and they change from: 5.88–6.04 μB for Mn(C8H6ClO3)24H2O, 3.96–4.75 μB for Co(C8H6ClO3)25H2O, 2.32–3.02 μB for Ni(C8H6ClO3)25H2O and 1.77–1.94 μB for Cu(C8H6ClO3)24H2O.

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Abstract  

Tin(II) complexes with 8-hydroxyquinolinate in solid state have been obtained by adding aqueous ammonium to a solution containing stannous chloride and 8-hydroxiquinoline in medium of HCl and acetone up to pH 5 and 9, respectively. The products obtained show the same composition, Sn(C9H6ON)2; however there are some differences regarding both the thermal behaviour in an oxidant atmosphere and morphology. These products were characterised by elemental and complexometric analysis, TG and DTA curves, infrared and X-ray diffractometry. TG curves show, above 448 K, the partial oxidation on air atmosphere of Sn(II) complexes to Sn(IV) complexes, SnO(C9H6ON)2. This behaviour does not depend only on pH in which the compounds were obtained but also on the heating rate in TG curves. Sn(II) complexes volatilise almost completely on nitrogen atmosphere and partially on air atmosphere depending on the oxidation degree of the compound.

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