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Abstract  

The bismuth salt of lauric (dodecanic) acid Bi6O4(OH)4(C11H23COO)6 was studied earlier. This salt has layer structure (the interlaminar distance=37.50 ), under heating this liquid-crystalline state has the mesomorphic transformation, turns to the amorphous state, decomposes stepwise with the formation of well-ordered layers of bismuth nanoparticles. DSC-curves were used for the study of the decomposition kinetics in the area of decomposition with small mass loss and exothermic effect (423–483 K).

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Abstract  

Two compounds of antimony trichloride and bismuth trichloride with valine are synthesized by solid phase synthesis at room temperature. Their compositions, determined by element analysis, are Sb(C5H10O2N)3·2H2O and Bi(C5H10O2N)2Cl·0.5H2O. The crystal structure of antimony complex with valine belongs to triclinic system and its lattice parameters are: a=0.9599 nm, b=1.5068 nm, c=1.9851 nm, α=92.270, β=95.050, γ=104.270. The crystal structure of bismuth complex with valine belongs to monoclinic system and its lattice parameters are: a=1.6012 nm, b=1.8941 nm, c=1.839 nm, β=99.73°. The far-infrared spectra and infrared spectra show that the amino group and carboxyl of valine may be coordinated to antimony and bismuth, respectively, in two compounds. The TG-DSC results also reveal that the complexes were formed.

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Thermal decomposition of bismuth laurates

Study of process kinetics

Journal of Thermal Analysis and Calorimetry
Authors: V. Logvinenko, K. Mikhailov, and Yu. Yukhin
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Introduction The VA main group metal compounds including inorganic and metallorganic complexes have been studied for decades owing to the interesting physical properties, medical and material functions [ 1 – 8 ]. Bismuth

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Journal of Thermal Analysis and Calorimetry
Authors: V. Logvinenko, A. Minina, Yu. Mikhaylov, Yu. Yukhin, and B. Bokhonov

Abstract  

Two bismuth salts, Bi6O4(OH)4(C17H35COO)6 and Bi6O4(OH)4(C17H35COO)6 nC17H35COOH, were synthesized. The thermogravimetry under quasi-isothermal conditions denotes the multi-step character of decomposition processes for both compounds. The thermogravimetry under linear heating was used for kinetic studies. Thermogravimetric data (obtained at different rates of linear heating) were processed with 'Netzsch Thermokinetics' computer program. Kinetic parameters were calculated only for the first decomposition step for both salts, the process is described by different nucleation equations (with and without autocatalysis).

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Journal of Thermal Analysis and Calorimetry
Authors: José Geraldo de P. Espínola, Evandro P. S. Martins, Franklin P. Aguiar, Haryane R. M. Silva, M. G. Fonseca, L. N. H. Arakaki, and Ercules E. S. Teotônio

Introduction The element bismuth, in its compounds, is found in various oxidation states, the most common being +3 and +5, as in bismuth halides [ 1 ] and bismuth derivatives with transition metals [ 2 – 4 ]. These two classes

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Abstract  

It was found that Po(IV) coprecipitates to a high degree with bismuth phosphate from weakly acidic solutions. The degree of coprecipitation of Po(II) under the same conditions is substantially lower. Coprecipitation with bismuth phosphate can be utilized for the separation of polonium from inorganic salts present in urine.

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Abstract  

The extraction of bismuth has been investigated in dependence of dilution and stoichiometry, using the reagents 8-hydroxyquinoline, N-benzyl-N-phenylhydroxylamine, diphenylthiocarbazone and substituted carbamates. Stripping of bismuth from organic solutions of the respective chelates using ligands such as EGTA, thioglycollic acid and 2,3-dimercaptopropane-1-sulfonate was also studied. It has been demonstrated that the equations proposed for determining the range of quantitative substoichiometric extraction are valid in the case of bismuth only at concentrations above 10−5 M Bi. At further dilutions (10−6–10−8 M), which would be of major interest in devising analytical methods based on the substoichiometric radioisotope dilution technique for determining bismuth at the trace level, the equilibria are shifted in favour of the competing hydrolytic reactions, so that the extraction is quantitative only with ammonium tetramethylenedithiocarbamate present in excess.

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Abstract  

Neutron activation analysis for bismuth in lead was performed through the separation and measurement of210Po, using two different extraction procedures. The reproducibility of the results was good for lead containing bismuth in higher concentrations. For high purity lead, variations in the bismuth content have been found by different analyses of the same sample, owing to inhomogeneity in the distribution of the Bi metal traces. An independent analysis of the same lead samples gave comparable Bi concentrations.

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Abstract  

The predominant use of the nuclear track technique (NTT) in analytical chemistry has been to measure the prompt charged particle emission from neutron induced reactions with stable or fissile nuclides of selected elements. This work describes the use of the NTT for determining bismuth via delayed alpha particle emission from the decay of210P. This technique is sensitive and reliable since alpha track counting is highly efficient and can provide information, on elemental spatial distributions. Bismuth determinations in various materials by this technique appears possible to at least the 1.0 microgram per gram level.

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