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This work presents investigations into the composition and some properties of nanodispersive powders of aluminum boride prepared by the plasma-recondensation technique. It is shown that, under a strictly determined aluminum : boron ratio in the starting mixture and with the complete observance of technological processing parameters, aluminum boride (n-AB) nanopowders of the required composition and dispersivity can be obtained. SEM investigations of the aluminum boride samples reveal that aluminum boride powders are mixtures of spherical particles of different sizes and a significant agglomeration of the particles is observed. In general, the sizes of particles are varied from several dozens of nanometers up to 500 nm and more. Investigations into the thermal-oxidative activity of synthesized aluminum boride using thermogravimetric and differential thermal analysis show that these compounds are more active towards air than nanodispersive aluminum. The highest rate of oxidation of aluminum borides was observed in the temperature range of 680-700°C.

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The use of analytical solutions for Frick`s diffusion equation to define the main sorption constants leading to the necessity to solve the united problem is shown. To be more exact this is the application assessment of analytical solutions for more often used experimental results and the determination of the representative sample dimensions in the experiments which are need to construct the sorption/desorption curves. By numerical experiments it is established that the most exact values of masstransfer constants are determined for small and middle values of diffuser absorption temporary process with the help of analytical solutions. Because of the difference in real sample dimensions and structural models used for analytical solutions which as a rule are presented in the form of semi-infinite plates it is necessary to minimize the influence of side surfaces in real samples on the accuracy of masstransfer parameters determination. The numerical-analytic study according to the geometry of polymeric samples from the point of view their representation to define diffusion, solubility and swelling coefficients is conducted. Herewith it is brought out that to obtain the values of masstransfer constants to an accuracy of not more 3 %, the sample geometric features must be chosen with relative dimensions L/h >10 (L – width, h – height of sample, accordingly) – the conditions of plane omnidirectional absorption of the diffuser into the right-angle-formed plates. To obtain the diffusion, solubility and swelling coefficients to an accuracy of not more 3 % the cylinder samples with relative dimensions D/h >15 (D – diameter, h – height, accordingly) should be preferably used. The algorithm of masstransfer constants determination when jointly use the sorption curves and the numerical method of diffusion analysis – finite element method is proposed. Herewith the advantages of such approach removing the sample size and shape limits are shown in comparison with the analytical methods of diffusion analysis.