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requirement of high cooling rates is fulfilled by this type of glass preparation. The crucial factor of preparation of these progressive materials in glassy form is the crystallization kinetics [ 3 – 8 ]. The crystallization kinetics of two binary

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compare the thermal stability and crystallization kinetics of 60B 2 O 3 –40PbO, 60B 2 O 3 –40Bi 2 O 3 , and 60B 2 O 3 –30Bi 2 O 3 –10PbO glasses. Thermal stability of these glasses were achieved in terms of the characteristic temperatures such as the glass

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. Pratap , A , Rao , TLS , Lad , KN , Dhurandhar , HD . Isoconversional vs model fitting methods. A case study of crystallization kinetics of a Fe-based metallic glass . J Therm Anal Calorim 2007 89 2 399 – 405 10.1007/s10973

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phase, the so called “rigid-amorphous phase” (RAP) or “inter-phase” between crystalline and amorphous layers has to be taken into consideration in these structures. In this view, herein the melting behavior and the isothermal crystallization kinetics of

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. In a series of investigations by Dalvi et al. [ 6 – 8 ], Ag + ion conductivity of mechanochemically synthesized samples, viz. AgI–Ag 2 O–M x O y (M x O y = V 2 O 5 , MoO 3 , CrO 3 ) has been thoroughly studied using crystallization kinetics by

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Abstract  

The effects of gamma irradiation on crystallization kinetics and microhardness properties of the Li2O–Al2O3–SiO2 (LAS) glass–ceramic sample have been investigated. The glass–ceramic was irradiated to γ-source 60Co of 0.7 MGy. The crystallization kinetics of the irradiated and non-irradiated samples were characterized using differential scanning calorimetry. The crystallization kinetics and microhardness properties of the glass–ceramic changed the gamma irradiation, and the high dose of gamma irradiation affects significantly the crystallization kinetics and microhardness properties of the Li2O–Al2O3–SiO2 glass–ceramic sample.

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This paper reports results on the crystallization kinetics of 35.5CaO–7.25La2O3–57.25B2O3 glass under nonisothermal conditions based on the studies carried out from the differential thermal analysis upon using various well-established models. The crystalline phases formed during the optimized ceramization process have been confirmed from the X-ray diffraction. The activation energies of the first (formation of CaLaB7O13) and second (formation of LaBO3) crystallization events have been estimated using the conventional methods of Kissinger, Augis–Bennett, Ozawa, and Matusita, and the results are found to be in good agreement with each other. The Avrami exponents that are determined by these models for the crystallization of CaLaB7O13 and LaBO3 are found to be in the range of (1.81–2.35) and (4.03–4.65), respectively. This indicates that the formation of CaLaB7O13 is dominated by a surface crystallization, whereas LaBO3 is formed by three-dimensional bulk crystallization with an increased rate of nucleation. This observation is further validated by microstructural investigation, which shows the formation of CaLaB7O13 phase as a surface layer and a bulk crystallization of LaBO3 in optimally ceramized samples.

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γ forms and dimensional distribution of spherulites of PP in composites. The investigation of crystallization kinetics on filler nucleating function, therefore, will give direct evidence of alteration of crystalline phase of PP in composites. The

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crystallization kinetics. Generally, studies of crystallization are limited to idealized conditions, in which external conditions are constant. In real situations, however, the external conditions change continuously, which make the treatment of non

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Abstract  

A crystallization kinetics analysis of several polypropylene-polyethylene (PP-PE), PP-rich copolymers was made by means of differential scanning calorimetry. The crystallization was studied via calorimetric measurements at different cooling rates. Several additives were added to the base material. Some test samples were subjected to artificial ageing processes. A modified isoconversional method was used to describe the crystallization process under non-isothermal conditions. The value of the Avrami parameter was determined for primary and secondary crystallization.

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