he effect of preparation conditions on the composition and structure of three-dimensional composite nanomaterials based on opal matrixes (packing of spherical particles of amorphous SiO2) has been studied. The experimental part of the work was performed with the samples of opal matrixes with a diameter of spherical SiO2 particles equal ~260 nm. Composite nanomaterials were formed by repeatedly filling of opal matrixes with solutions of metal salts (oxides) and holding the samples at 623–723 K, and after that, they were annealed at 973–1473 K. Chemical reactions and phase transformations of substances in nanopores of opal matrixes depended on the annealing parameters, and chemical properties of intermediate compounds. There was confirmed the formation of SiO2 crystallites in nanopores of composite nanomaterials, as well as the products of their interaction with SiO2. Composite nanomaterials with filling of opal matrix nanopores with metals, ferroelectrics and piezoelectrics, multiferroic and other substances have been obtained. The resulting composite nanomaterials had ordered components (substances) with a given composition and crystallite size in the range of 10–90 nm. The influence of the composition and structure of composite nanomaterials containing ferromagnetically ordered nanostructured magnetic orthovanadates of rare-earth metals, Ni-Zn-Fe-, Co-Zn-Fe-spinel, and also Co and Ni together, on their properties was demonstrated. Present research was executed under financial support by RFBR (Grant N 18-29-02076).

Ивана Франко 4 3 Научно-исследовательский институт ядерной физики им. Д.В. Скобельцына Московского государственного университета им. М.В. Ломоносова, 119991, Москва, Ленинские горы 1, строение 2 4 Московский физико-технический институт (государственный университет), 141701, Долгопрудный, Институтский переулок, 9 Статья поступила в редакцию 6 июня 2019 г. orthosiliconic acid (Si(OS 2 H 5) 4). In the experiments, the samples of opal matrixes in the form of plates with 1-5 mm thick were used. The paper presents the results of measuring the X-ray energy spectra induced by pulsed laser impacts on opal matrixes at wavelengths (): 1040 nm (IR), 510 nm jointly with 578 nm, 366 nm (UV). According to the results of spectral studies, it was found that the induced X-rays are low-intensity soft X-radiation with photon energy of 0.08-2.47 keV and with wavelength of 15.2-0.5 nm. The impact on the opal matrix by laser radiation in the UV range causes the intense luminescence of opal matrixes in the visible light range.

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The conditions for the formation of opal matrixes representing the lattice packing of spheric particles SiO 2 with diameter ~260 nm (Δd < 4%) and singledomain size (regions with proper packing of spheric particles) ≥ 0,1 mm 3 are presented. The processes for obtaining of 3D magnetic nanocomposites by synthesis of NiXZn1-XFe2O4 and CoXZn1-XFe2O4 crystallites in communicating spatially ordered inter-spherical voids, occupying ~ 26% of the volume of the opal matrix, are shown. The composition and structure of nanocomposites were researched by electron microscopy and X-ray diffractometry. The results of using samples of magnetic nanocomposites containing Ni0.5Zn0.5Fe2O4 and Co0.5Zn0.5Fe2O4 crystallites of 15-50 nm in size as inserts in Y circulators are discussed.

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