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2 O 3 are widely studied [ 9 – 11 ]. High energy ball-milling is a low cost, simple operation method for preparing extended solid solutions and nanoparticle systems. To the best of our knowledge, there is no literature available on the ball-milling

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Resolution and Discovery
Authors: K. Tomolya, D. Janovszky, A. Sycheva, M. Sveda, T. Ferenczi, and A. Roósz

. Dutkiewicz J , Jaworska L , MaziarzW, Czeppe T , Lejkowska M , Kubicek M , Pastrnák M : Consolidation of amorphous ball-milled Zr–Cu–Al and Zr–Ni–Ti–Cu powders . J Alloys Compd 434–435 , 333 – 335 ( 2007

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obtain Fe–20 wt% Mn–6 wt% Si–9 wt% Cr powder. It is well known that the main characteristic of these materials with shape memory effects is diffusionless phase transformation i.e., martensitic transformations. In this study, therefore, various ball-milling

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Journal of Thermal Analysis and Calorimetry
Authors: Giovanna Bruni, Vittorio Berbenni, Franco Sartor, Chiara Milanese, Alessandro Girella, Dionigio Franchi, and Amedeo Marini

aim of this work was to evaluate the possibility to obtain a drug into the amorphous phase by high energy ball-milling. Also we were aimed to find a method to quantify the amorphous part of a drug that, in this work, is a glycine receptor antagonist

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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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Summary  

It has been presented that the bulk mechanical alloying occurring in the Ni-hydroxycarbonate-aluminium mixture can produce homogeneously refined composite of nickel aluminides with aluminium oxide. The control of mechanochemical phenomenon was carried out by phase identification of milling products as well as their structural and morphological characterization. As a result the thermoanalytical and X-ray powder diffraction measurements as well as scanning electron microscopy with backscattered electron images (BSE) and X-ray energy dispersive spectroscopy (EDS) were applied. It was found that the kinetics of mechanochemical reactions depends on the chemical nature of initial salt.</o:p>

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mechanochemical activation by the ball-milling method. The effect of particle sizes on the thermal behavior was investigated by means of simultaneous DSC–TG measurements in argon atmosphere up to 800 °C. The thermal stability of hematite in dry air atmosphere was

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Journal of Thermal Analysis and Calorimetry
Authors: Giovanna Bruni, C. Milanese, G. Bellazzi, V. Berbenni, P. Cofrancesco, A. Marini, and M. Villa

Abstract  

The processes of production of drugs and dosage forms in the solid state often cause unwanted transformation of portions of the substances into amorphous state, with significant changes of properties such as stability and bio-availability. When this amorphous fraction is of the order of a few percent, it usually goes unnoticed, but it should be accurately determined within a quality control system. In this work, we consider a model drug, perphenazine, where partial amorphisation may be induced by standard mechanical treatments. We show that Differential Scanning Calorimetry (DSC) leads to consistent estimations of the amorphous fractions induced by the treatment. Furthermore, DSC also yields the expected amounts of amorphous perphenazine when analysing known mixtures of perfectly crystalline samples (untreated) and partially amorphous samples (treated). We show that even amorphous fractions of the order of 1% are accurately estimated by our method.

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information on this kaolinite and its chemical composition were reported elsewhere [ 1 , 17 ]. The raw kaolinite was wet milled in planetary ball mill with alumina grinding media for 5 h, then attrition milled for 1 h using ZrO 2 balls (diameter of 1. 2 μm

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–Al 2 O 3 ceramic composite. The constituent powders, which were prepared with designed stoichiometry according to reaction ( 1 ), were exposed to the milling process in a ball-mill. Four samples (marked by S 1 to S 4 ) were ball-milled for 5

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