The reduction of chlorocomplexes of gold(III) from muriatic solutions by nanocrystal powders of palladium and platinum at 110 and 130 °C under hydrothermal conditions and the action of microwave irradiation has been investigated. The structure and composition of the solid phase have been characterized by transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and chemical methods. Bimetallic particles with a core-shell structure have been revealed. The obtained particles are established to have a core of the metal reductant covered with a substitutional solid (Au, Pd) solution in case of palladium, and isolated by a gold layer in the case of platinum. The main reason for such a difference is the ratio between the rates of aggregation and reduction. It has been shown by the example of the Au-Pd system that the use of microwave irradiation allows us not only to accelerate the synthesis of particles but also to obtain more homogeneous materials in comparison with conventional heating.

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Обжигом на воздухе в интервале температур 1273−1473 K из исходных оксидов Sm 2 O 3 , Ga 2 O 3 и GeO 2 твердофазным синтезом получен SmGaGe 2 O7. Методом рентгеновской дифракции определена структура исследованного германата (пр. гр. P2 1 /c; a = 7.18610(9) ¦ , b = 6.57935(8) ¦ , c = 12.7932(2) ¦ ). С использованием дифференциальной сканирующей калориметрии измерена его высокотемпературная теплоемкость. Полученные экспериментальные данные C p = f (T ) позволили рассчитать термодинамические свойства соединения.Ключевые слова: галлий германат самария, структура, теплоемкость.