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] are the main among the described methods in technical literature. One of these methods is also thermal treatment. Asbestos minerals are naturally occurring hydrous silicates, so that they decompose to release water by heating at high

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Journal of Thermal Analysis and Calorimetry
Authors: Juliusz Leszczynski, Krzysztof T. Wojciechowski, and Andrzej Leslaw Malecki

structure. Phase diagram for the Co-Sb system is well known [ 1 ]. CoSb 3 is the δ phase, which is stable up to 874 °C. Above this temperature it undergoes peritectic decomposition into liquid and CoSb 2 γ phase, stable up to 936 °C. In recent times

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, C. W. , The Decomposition Theorem for Ideals in Polynomial Rings over a Domain, Journal of Algebra , 76 (1982), 99–110. Ayoub C. W. The Decomposition Theorem for Ideals in

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methods [ 6 – 8 ]. These investigations enable the activation energies for decomposition, decomposition rate constants at different temperatures, and thermal ranges of decomposition to be determined. The kinetic data enables the conditions of

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mechanical properties of obtained elements, nevertheless it is classified as strong neurotoxin and probably carcinogenic substance [ 8 ]. Second, it contains a nitrogen atom in a molecule, so during binder decomposition nitrogen oxides are released into the

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transition metal ions with organic ligands, it is customary to investigate the thermal decomposition of these complexes so as to obtain useful data on the metal–ligand bonds [ 2 – 4 ] and stability trends. The thermal investigations on some derivatives of

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Journal of Thermal Analysis and Calorimetry
Authors: Lucjan Chmielarz, Małgorzata Rutkowska, Piotr Kuśtrowski, Marek Drozdek, Zofia Piwowarska, Barbara Dudek, Roman Dziembaj, and Marek Michalik

obtained for a relatively large group of di- and trivalent metal cations in a broad range of these metal loadings [ 1 ]. Thermal decomposition of hydrotalcite-like materials at middle temperatures ( T < 600 °C) results in the formation of the relatively

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Journal of Radioanalytical and Nuclear Chemistry
Authors: A. Bojanowska-Czajka, H. Nichipor, P. Drzewicz, B. Szostek, A. Gałęzowska, S. Męczyńska, M. Kruszewski, Z. Zimek, G. Nałęcz-Jawecki, and M. Trojanowicz

Abstract  

The radiolytic degradation of widely used fungicide, carbendazim, in synthetic aqueous solutions and industrial wastewater was investigated employing γ-irradiation. The effect of the absorbed dose, initial concentration and pH of irradiated solution on the effectiveness of carbendazim decomposition were investigated. Decomposition of carbendazim in 100 μM concentration in synthetic aqueous solutions required irradiation with 600 Gy dose. The aqueous solutions of carbendazim have been irradiated in different conditions, where particular active radical species from water radiolysis predominate. The obtained data have been compared with the kinetic modeling. The reversed-phase high-performance liquid chromatography was used for the determination of carbendazim and its radiolytic decomposition products in irradiated solutions. The changes of toxicity of irradiated solutions were examined with different test organisms and human leukemia cells.

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Abstract  

Two types of ammonium uranyl nitrate (NH4)2UO2(NO3)4·2H2O and NH4UO2(NO3)3, were thermally decomposed and reduced in a TG-DTA unit in nitrogen, air, and hydrogen atmospheres. Various intermediate phases produced by the thermal decomposition and reduction process were investigated by an X-ray diffraction analysis and a TG/DTA analysis. Both (NH4)2UO2(NO3)4·2H2O and NH4UO2(NO3)3 decomposed to amorphous UO3 regardless of the atmosphere used. The amorphous UO3 from (NH4)2UO2(NO3)4·2H2O was crystallized to γ-UO3 regardless of the atmosphere used without a change in weight. The amorphous UO3 obtained from decomposition of NH4UO2(NO3)3 was crystallized to α-UO3 under a nitrogen and air atmosphere, and to β-UO3 under a hydrogen atmosphere without a change in weight. Under each atmosphere, the reaction paths of (NH4)2UO2(NO3)4·2H2O and NH4UO2(NO3)3 were as follows: under a nitrogen atmosphere: (NH4)2UO2(NO3)4·2H2O → (NH4)2UO2(NO3)4·H2O → (NH4)2UO2(NO3)4 → NH4UO2(NO3)3 → A-UO3 → γ-UO3 → U3O8, NH4UO2(NO3)3 → A-UO3 → α-UO3 → U3O8; under an air atmosphere: (NH4)2UO2(NO3)4·2H2O → (NH4)2UO2(NO3)4·H2O → (NH4)2UO2(NO3)4 → NH4UO2(NO3)3 → A-UO3 → γ-UO3 → U3O8, NH4UO2(NO3)3 → A-UO3 → α-UO3 → U3O8; and under a hydrogen atmosphere: (NH4)2UO2(NO3)4·2H2O → (NH4)2UO2(NO3)4·H2O → (NH4)2UO2(NO3)4 → NH4UO2(NO3)3 → A-UO3 → γ-UO3 → α-U3O8 → UO2, NH4 UO2(NO3)3 → A-UO3 → β-UO3 → α-U3O8 → UO2.

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, Canyon Diablo, and Odessa in the temperature range of spinodal decomposition (below 500 °C) were cooled at rates of about 7–15 K/Myr. The presence of dendrites indicates the crystallization of the shock melt. The average size (26 μm) of dendrites in the

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