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The results of studying painted areas on the surface of the Bronze Age anthropomorphic stela, found in the village of Remontnoye, are presented. The elemental and phase composition of the samples has been studied using X-ray diffraction and electron microscopy. It is established that the red color on the front surface of the stela is due to the red mineral pigment based on hematite, while the dark and green areas are of natural origin, associated with the environmental impact on the sandstone. [ABSTRACT FROM AUTHOR]

The microstructure of the membrane alloy Pd-9.1 at Y has been studied by X-ray diffraction using synchrotron radiation and transmission electron microscopy with electron diffraction. It has been shown that the matrix phase in the alloy has a face-centered cubic lattice. The presence of Guinier–Preston zones and formation of the ordering of the alloy atoms have been determined. The presence of defects enriched with atoms of the same type has been revealed. The deformation fields they create have been studied. [ABSTRACT FROM AUTHOR]

A medieval Russian bronze pendant icon with enamel images, dated to the period from the 12th to the first half of the 13th century was studied. The investigation was performed using neutron and synchrotron tomography, X-ray fluorescence analysis, and neutron and synchrotron X-ray diffraction analysis. The product was found to have no strips dividing enamels of different colors, whereas strip fragments were revealed deep in the enamel layer. The pendant fabrication technology has been reconstructed. [ABSTRACT FROM AUTHOR]

The influence of proton irradiation on the structure of Nb3Sn superconducting materials has been investigated. The irradiation to different proton doses was performed on a cyclotron at the National Research Centre "Kurchatov Institute" (NRC KI). The Nb3Sn samples were placed successively pairwise on the beam axis to obtain different degrees of radiation-induced damage at a specified dose. X-ray diffraction (XRD) analysis of irradiated and unirradiated samples was carried out on a synchrotron radiation source at the NRC KI. The results of studies revealed that the diffraction peaks broaden and become weaker with an increase in the concentration of radiation-induced defects. The phase compositions of the samples and dynamics of changes in the found NbO phase under irradiation have been investigated. The change in the lattice period for the irradiated samples is studied. It is shown that the lattice period increases with an increase in concentration of radiation-induced defects. [ABSTRACT FROM AUTHOR]

Order–disorder structural transformations in xR2O3 ∙ (1 – х)TiO2 (R = Tm, Er; х = 0.5−0.6) solid solutions with a highly imperfect fluorite-derived structure at 1600°C have been studied using monochromatic synchrotron X-ray diffraction and Raman spectroscopy. The results demonstrate that the synthesis process leads to the formation of two cubic phases identical in composition: a disordered fluorite-like (F) phase (Fm3m) and an ordered pyrochlore-like (P) phase (Fd3m), which is coherent with the disordered phase and consists of nanoscale (<100 Å) and nanocrystalline domains. The lattice parameters of these phases have been determined. In the stability range of the solid solutions ((0.5 ≤ x ≤ 0.6)), the lattice parameter of the fluorite-like phases follows Vegard's law. The Raman spectra of the R2TiO5-based (R = Tm, Er) solid solutions contain broad bands at low and high frequencies, with peaks at 100, 171, 291, 355, 385, and 723 cm–1 for R = Tm and at 100, 169, 292, 355, 390, and 720 cm–1 for R = Er, which correspond to the P- and F-phases, respectively. The formation of pyrochlore-like phases with different degrees of order in a fluorite matrix is due to the internal stress induced by the high density of structural defects in their unit cells. The materials obtained in this study have a large specific surface area and can be used as catalysts and catalyst supports. [ABSTRACT FROM AUTHOR]

Abstract: Among the important antiquities of Altai Bronze Age, Karakol burial site (dated to the beginning of the 2nd mill. BCE) can be selected. The images are overlapped; the ones synchronous to the burial ritual were performed in a complex technique, including painting, pecking, engraving, and abrasion. Studies at the National Research Centre "Kurchatov Institute" (NRC KI), including scanning electron microscopy combined with X-ray microanalysis and powder X-ray diffraction on the Belok station (Kurchatov synchrotron radiation source (KSRS)), revealed that red (ochres of different hues) and black (soot) pigments were used to to produce paint at the Karakol site. An analysis of the red paints showed their composition to be homogeneous within one burial but differ from burial to burial. An analysis of the colored line on slab 1 (Karakol, burial 3, mound 2) made it possible to establish its natural origin and reasonably reject the hypothesis that it was painted. [ABSTRACT FROM AUTHOR]

order-disorder phenomena in nanocrystalline Gd2ZrO5with highly imperfect fluorite- derived structures in the range 1000-1600°C have been studied using monochromatic synchrotron X-ray diffraction and Raman spectroscopy. The results demonstrate that the synthesis process leads to the formation of two coherent phases identical in composition: a nanocrystalline disordered fluorite-like (F) phase (Fm3m) and a nanoparticulate ordered fluorite derivative (C1) (Ia3). Their lattice parameters have been determined. In the range 1000-1600°C, the Raman spectra of the Gd2ZrO5 and Gd2HfO5 materials contain broad bands in low- and high-frequency regions, at ∼118 (108), 362 (353), and 670 (665) cm-1, which characterize the C1 and F phases, respectively. [ABSTRACT FROM AUTHOR]

Order-disorder transitions in xRO · (1 − x)TiO (R = Sc, 0.4 ≤ x ≤ 0.5; R = Y, 0.5 ≤ x ≤ 0.6) solid solutions with highly imperfect fluorite-derived structures have been studied using monochromatic synchrotron X-ray diffraction and Raman spectroscopy. The results demonstrate that the synthesis process leads to the formation of a fluorite-like ( Fm3 m) disordered phase and a nanoscale (~10-100 nm) pyrochlore-like ( Fd3 m) ordered phase of the same composition, coherent with the disordered phase. We have determined their lattice parameters. The Raman spectra of ScTiO (YTiO) contain broad lines in low- and high-frequency regions: at 190, 350, and 775 (134, 188, 365, 404, and 727) cm. These lines are characteristic of a pyrochlore-like phase with a varying degree of order and a disordered fluorite-like phase, respectively. The pyrochlore-like phase YTiO has two strong Raman peaks in the low-frequency region: at 312 and 527 cm. The formation of nanodomains with different degrees of order is caused by the internal stress that arises from the high density of structural defects in the unit cells of the solid solutions. [ABSTRACT FROM AUTHOR]

X-ray diffraction characterization with monochromatic synchrotron X-rays has demonstrated that xScO · (1 − x)TiO ( x = 0.4-0.5) solid solutions consist of a fluorite-like ( Fm3 m) disordered phase and a nanoscale (≃ 10-50 nm) pyrochlore-like ( Fd3 m) ordered phase of the same composition, coherent with the disordered phase. We have determined their lattice parameters. The formation of nanodomains with different degrees of order is shown to be caused by the internal strain due to the high density of structural defects in their unit cells. The materials obtained in this study possess enhanced sorption capacity and can be used as catalysts, catalyst supports, gas sensors, etc. [ABSTRACT FROM AUTHOR]

X-ray diffraction characterization with monochromatic synchrotron X-rays has demonstrated that xYO · (1 − x)TiO ( x = 0.5-0.58) solid solutions consist of a fluorite-like ( Fm3 m) disordered phase and a nanoscale (≃40-1000 nm) pyrochlore-like ( Fd3 m) ordered phase of the same composition, coherent with the disordered phase. In the composition range of the solid solutions (0.5 ≤ x ≤ 0.58), the lattice parameter of the fluorite-like phase follows Vegard's law. The formation of nanodomains with different degrees of order is shown to be caused by the internal strain due to the high density of structural defects in their unit cells. The materials obtained in this study possess enhanced sorption capacity and can be used as catalysts, catalyst supports, gas sensors, etc. [ABSTRACT FROM AUTHOR]

Monochromatic synchrotron X-ray diffraction data demonstrate that single-crystal and polycrystalline xErO · (1 − x)TiO ( x = 0.5-0.6) solid solutions consist of a fluorite-like disordered ( Fm3 m) phase and a nanoscale (40-1000 nm) pyrochlore-like ordered phase ( Fd3 m) of the same composition in the range 0.5 ≤ x ≤ 0.57, coherent with the disordered phase. Reducing the density of structural defects in the unit cell of ErTiO ( x = 0.6) leads to a structural transformation of the pyrochlore-like phase into a TaO-type ordered phase ( Ia3), derived from the fluorite phase. In the composition range of the solid solutions (0.5 < x < 0.6), the lattice parameter of the fluorite-like phase follows Vegard's law. The formation of nanodomains with different degrees of order is shown to be caused by the internal strain due to the high density of structural defects in their unit cells. [ABSTRACT FROM AUTHOR]