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Abstract  

The synthesis of new compounds based on Bi2O3 is investigated because they can be used as new environmentally friendly inorganic pigments. Chemical compounds of the (Bi2O3)1–x(Er2O3)x type were synthetized. The host lattice of these pigments is Bi2O3 that is doped by Er3+ ions. The incorporation of doped ions provides interesting colours and contributes to an increase in the thermal stability of these compounds. The simultaneous TG-DTA measurements were used for determination of the temperature region of the pigment formation and thermal stability of pigments.

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Journal of Thermal Analysis and Calorimetry
Authors: Petra Šulcová, Eva Proklešková, Pavel Bystrzycki, and Miroslav Trojan

Abstract  

New inorganic compounds having the general formula (Bi2O3)1−x(Lu2O3)x (x ranges from 0.1 to 0.5) displaying orange colours have been synthesized by traditional solid-state route, as viable alternatives to lead, cadmium and chromium based yellow toxic inorganic pigments. The host lattice of these pigments is Bi2O3 that is doped by Lu3+ ions. The goal was to develop conditions for the synthesis of these compounds and to determine the influence of calcination temperature and lutetium content on their colouring effects. The simultaneous TG-DTA measurements were used for determination of the temperature region of the pigment formation and thermal stability of pigments. The pigments were also evaluated from the standpoint of their structure and particle sizes.

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Abstract  

The synthesis of new compounds based on Bi2O3 is investigated because they can be used as new ecological inorganic pigments. Chemical compounds of the (Bi2O3)1−x(Y2O3)x type were synthesized. The host lattice of these pigments is Bi2O3 that is doped by Y3+ ions. The incorporation of doped ions provides the interesting colours and contributes to a growth of the thermal stability of these compounds. The simultaneous TG-DTA measurements were used for determination of the temperature region of the pigment formation and thermal stability of pigments. This paper also contains the results of the pigment characterization by X-ray powder diffraction and their colour properties.

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Abstract  

The study of the system xSb2O3–(1 − x)Bi2O3–6(NH4)2HPO4 has been carried out to identify the phases and simulate the mechanisms of their formation, using the technique of thermal analysis in association with X-ray diffractometry. The main stages observed during thermal treatment of the samples include: (1) elimination of water and ammonia leading to the formation of (NH4)5P3O10; (2) reaction of the latter with M2 IIIO3 and the formation of acidic polyphosphates M2 IIIH2P3O10; (3) their dehydration with the formation of the polyphosphates MIII(PO3)3. Then Sb(PO3)3 decomposes giving SbPO4 and P2O5. In the presence of excessive P2O5, two moles of Bi(PO3)3 condensate into oxophosphates Bi2P4O13 and BiP5O14. The data of thermal analysis match with the composition of intermediate and final products. The hygroscopicity of the samples diminishes with growing bismuth content.

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Abstract  

The synthesis of new compounds based on the Bi2O3–Ho2O3 system, which can be used as new ecological inorganic pigments, is investigated in our laboratory. The optimum conditions for the syntheses of these compounds have been followed by the methods of thermal analysis that can provide first information about the temperature region of the pigment formation. The synthesis of these compounds was followed by thermal analysis using STA 449/C Jupiter (Netzsch, Germany).

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Abstract  

The interactions between MoO3 and Sb2O3 or α-Sb2O4 taking place in the solid state in air during high-temperature as well as mechanochemical treatments have been investigated. The high-energy ball milling of MoO3 with Sb2O3 converts α-Sb2O3 to β-Sb2O3 and leads to formation of Sb2MoO6 and Sb4Mo10O31 phases. They are the final products of thermal synthesis in an inert atmosphere but not in air. The solid solution of MoO3 in β-Sb2O4 was obtained in high-temperature reaction of MoO3 with Sb2O3 or α-Sb2O4 as well as by milling of mixture MoO3/α-Sb2O4 for 14 h. The milling resulted in higher than 3 mol% solubility of MoO3 in β-Sb2O4. The constructed phase diagram of MoO3–α-Sb2O4 system is presented.

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0.62608(18) 0.23262(13) 0.42688(12) 0.0335(7) O31 1 0.36129(18) 0

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) and fly ash. To obtain sprayable compositions, we used industrially available sodium silicate N42 (Coogee, Australia) solution with SiO 2 :Na 2 O = 3.1 and density 1.42 g/cm 3 . The water:cement mass ratio is very important when applying coatings by

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data (in wt%) were as follows: for tin oxalate Sn = 57%, C = 12% and O = 31%; for tin sodium EDTA Sn = 34%, Na = 6%, N = 2%, C = 17%, H = 4%, and O = 32% (without water oxygen (∼5%) at least for tin sodium inositol-hexaphosphate Sn = 12.6%,Na = 16.7%, C

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H 2 O 31.36 31.04 31.17 61.70 62.01 6.94 6.82 18.51 18.40 10

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