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The behaviour of the promising glass sealant 54.4SiO2-13.7Na2O-1.7K2O-5.0CaO-12.4MgO-0.6Y2O3-11.3Al2O3-0.9B2O3 for solid oxide fuel cells (SOFCs) under SOFC operating conditions was studied. First, the kinetics of the crystallisation processes at the operating temperature (850 °C) was discussed (maximum exposure time of 1000 h), and the effect of crystallisation on the coefficient of thermal expansion (CTE) of the sealant was studied. Furthermore, the degradation processes at the interface of the glass sealant and functional SOFC materials (Crofer 22 APU, YSZ, and NiO(Ni)-YSZ) during exposure to 850 °C in oxidising and reducing atmospheres for 500 h were studied. The tests demonstrated good performance of the sealant studied and possibility of its application in SOFCs.

Resume. The purpose of the study was to reveal the main features of the development of purulent mediastinitis in a wounded person with penetrating gunshot wounds of the chest and neck in order to further improve the diagnosis and treatment of this difficult complication. The work reports on the injured K., 29 years old, with acute purulent-necrotic mediastinitis and late bilateral empyema of the pleura caused by a gunshot wound to the chest and neck. With early diagnosis of suppurative mediastinitis due to penetrating gunshot wounds of the chest and neck, active surgical tactics including wound dressing, drainage, massive antibiotic therapy, and adequate postoperative care with intensive care generally help to save the patient's life.

Composite ceramics of titanium nitride grains incorporated in an aluminium nitride matrix have been synthesized by high pressure high temperature treatment of a mechanical mixture of AlN–TiN (3 mol % TiN) powders. The microstructure of the samples analysed by means of electron beam microanalysis and Raman spectroscopy shows that the formation of cubic AlN in the composite begins near titanium nitride grains. The areas of mixed chemical composition, which can be assigned to the formation of the solid solutions Al1−xTixN, have been observed at the phase interfaces. The luminescence properties of AlN–TiN ceramics have been considered focusing on the choice of high pressure and high temperature treatment conditions. Three main components at 2.0 eV, 2.4 eV and 3.1 eV are revealed in the cathodoluminescence spectra analysed quantitatively. The observed emission originates from the radiative transitions with participation of valence band states, oxygen-vacancy centres (VAl–ON), nitrogen vacancies VN, and shallow donors which form a complex system of energy levels in the bandgap of the wurtzite-type AlN.

A clinoenstatite rim occurs in many refractory forsterite-rich objects; however, specialized studies of it have not been carried out. The first data from the study of refractory forsterite-rich objects by electron backscatter diffraction (EBSD) are reported. It is shown that the clinoenstatite rim in refractory forsterite-rich inclusions has a reactionary nature and was formed as a result of nebular processes. The rim is almost entirely composed of clinoenstatite. Forsterite grains have a block internal structure with a maximum misorientation angle of 10° within a single crystal.

—In the section of the sedimentary cover of the East European Platform, the new Sabantuy chromite ore occurrence was revealed. It is localized in Upper Kazanian sandstones of the erosional terrace above the floodplain of Malaya Berkutla Creek in the south-west of the Republic of Bashkortostan. The article presents the first results of geological, lithological, and mineralogical–geochemical studies of the new ore occurrence with signatures of an ancient coastal–marine placer. The Cr2O3 content in chromite sandstones (chromitolites) is 15.9–17.2 wt %. The bulk of the heavy fraction (67%) is composed of sub-angular and sub-rounded Cr-spinel grains 0.15–0.25 mm in size. Their mineralogical features indicate proximity to Cr-spinels from ultramafic rocks of ophiolite complexes.

Summary. The article presents the data of local application of a 0.02 % decasan solution in patients with traditional «open» obviously clean planned surgical interventions on the gastrointestinal tract without perioperative antibiotic prophylaxis. Objective: to provide intraoperative protection of traditional “open” clean planned surgical interventions and to achieve the prevention of purulent-inflammatory complications through local clinical use of decasan without perioperative antibiotic prophylaxis. Materials and methods. The study involved 63 patients who were treated at the clinic of the State Institution «Institute of General and Emergency Surgery named after V. T. Zaitsev NAMS of Ukraine» and operated in a planned manner regarding umbilical and inguinal hernia. He performed the traditional «open» clean surgical interventions — hernioplasty. All patients participating in the study were divided into two groups. The main group consisted of 29 (46.1 %) people who, for the purpose of intraoperative protection of the performed interventions, were locally irrigated with the cavity of the surgical wound and suture line with a solution of universal antiseptic decasan, 1 ml of which contains 0.2 mg of decamethoxin, without perioperative antibiotic prophylaxis. The comparison group consisted of 34 (53.9 %) people who underwent antibiotic prophylaxis with parenteral administration of 1.0 g cefipime during the perioperative period. Results. When conducting a preliminary bacteriological study of smears performed intraoperatively in patients in the group with clinical use of decasan by soaking all the walls of the surgical wounds (initial data before treatment with the drug), the absence of pathological microflora growth was revealed. Conclusions. It is concluded that the local clinical use of decasan in patients with gastrointestinal tract pathology when performing “open” obviously clean planned surgical interventions fully ensures their adequate intraoperative protection without perioperative antibiotic prophylaxis.

X-ray diffraction and Mossbauer spectroscopy with optical microscopy, electron probe microanalysis and Raman spectroscopy were used for the study of Janisjarvi impactite. The phase composition of impactite was determined and Mossbauer parameters of spectral components were estimated and related to the corresponding iron-bearing phases.

Finite deformation patterns of accessory phases can indicate the tectonic regime and deformation history of the host rocks and geological units. In this study, tectonically deformed, seismically deformed, and shocked zircon grains from a granite sample from the core of the Vredefort impact structure were analyzed in situ, using a combination of Raman spectroscopy, backscatter electron (BSE) imaging, electron backscattered diffraction (EBSD) mapping, electron probe microanalyses (EPMA), energy-dispersive X-ray spectroscopy (EDS) qualitative chemical mapping, and cathodoluminescence (CL) imaging. We aimed to reveal the effects of marginal grain-size reduction, planar deformation bands (PDBs), and shock microtwins on the crystal structure and microchemistry of zircon. Deformation patterns such as PDBs, microtwins, and subgrains did not show any significant effect on zircon crystallinity/metamictization degree or on the CL signature. However, the ratio of Raman band intensities B1g (1008 cm–1) to Eg (356 cm–1) slightly decreased within domains with low misorientation. The ratio values were affected in shocked grains, particularly in twinned domains with high misorientation. B1g/Eg ratio mapping combined with metamictization degree mapping (full width at half maximum of B1g peak) suggest the presence of shock deformation features in zircon; however, due to the lower spatial resolution of the method, they must be used in combination with the EBSD technique. Additionally, we discovered anatase, quartz, goethite, calcite, and hematite micro-inclusions in the studied zircon grains, with quartz and anatase specifically being associated with strongly deformed domains of shocked zircon crystals.

Fe–Mg carbonate metasomatites in the limestones of the Suran suite of the Lower Riphean in the Avzyansky ore district of the Bashkir meganticlinorium are represented by large deposits of Fe-magnesite (Ismakaevo deposit) and breinerite stocks (Bogryashka deposit). The metasomatic zonality is represented by a series of limestone — dolomite — Fe-magnesite (breinerite). Ferrous magnesite contains up to 8 mol. % FeСO3. In breinerite iron saturation varies from 10 to 45 mol. % FeСO3. The metasomatic fluid was a brine of Ca, Na, Mg chlorides with an impurity of Fe, and was connected with the remobilization processes of evaporite brines buried in sediments of the Lower Riphean. The salinity and homogenization temperature of fluid inclusions in magnesites are in the range of 20–26% eq. NaCl and 200–240°C, and in breinerites — 10–15% eq. NaCl and 140–190°C, respectively. The interaction of fluid with terrigenous rocks in the tectonically active zone of the Mashak riftogenic graben led to the enrichment of various ligands and more active hydrothermal redeposition in the metasomatic products of medium and heavy lanthanides. During the migration of fluid through the limestone unite in the cooling process, Fe-magnesite of the Ismakaevo deposit was formed in the frontal zone, and the breinerite of Bogryashka deposit — in the rear zone adjacent to the shale source of brine.

The polygenic and polychronous character of the texture (heterogeneity of the chemical and isotope composition, degree of crystallinity, stress, etc.) of zircon is the key source of information on the conditions of its growth and secondary alterations. The JPD method of processing of the BSE and CL images including plotting of JPD histogram and JPD map of grains was developed and tested in this research for quantitative study of the internal texture of zircon grains with micron spatial resolution and its application in geochronometry. Based on the concentration of impurities (Cameca SX100 micoanalyzer), the parameters of the Raman spectra, and photoluminescence (Horiba LabRam HR800 Evolution spectrometer), the nomenclature for distinguishing individual zones on the generalized diagram (BSE vs. CL) is suggested for zircons of a wide range of the conditions of the formation, age, size, texture types, and degrees of structure disordering. The JPD-analysis of the zoned texture of zircon grains is applied for interpretation of the nature of variations in the BSE and CL intensities within an individual heterogeneous grain on the quantitative level, and between the different grains, on the qualitative level, as the preliminary stage during geochronological studies increasing the reliability of the local electron microprobe and mass spectrometry isotope studies of the mineral.

The Vredefort impact structure, South Africa, is a 2.02 Ga deeply eroded meteorite scar that provides an opportunity to study large impact craters at their lower stratigraphic levels. A series of anomalous granophyre dikes in the core of the structure are believed to be composed of an impact melt, which intruded downwards from the crater floor, exploiting fractures in basement rocks. However, the melt emplacement mechanisms and timing are not constrained. The granophyre dikes contain supracrustal xenoliths captured at higher levels, presently eroded. By studying these clasts and shocked minerals within, we can better understand the nature of dikes, magnitude of impact melt movement, conditions that affected target rocks near the impacted surface, and erosional rates. We report “former reidite in granular neoblastic” (FRIGN) zircon within a granite clast enclosed in the granophyre. High-pressure zircon transformation to reidite (ZrSiO4) and reversion to zircon resulted in zircon grains composed of fine neoblasts (∼0.5–3 µm) with two or three orthogonal orientations. Our finding provides new independent constraints on the emplacement history of Vredefort granophyre dikes. Based on the environment, where other FRIGN zircons are found (impact glasses and melts), the clast was possibly captured near the top of the impact melt sheet and transported to the lowermost levels of the structure, traveling some 8–10 km. Our finding not only provides the highest-pressure shock estimates thus far discovered in the Vredefort structure (≥30 GPa), but also shows that microscopic evidence of high shock pressures can be found within large eroded craters at their lowest stratigraphic levels.

Nanodispersed TiO2 consisting of anatase and brookite phases in a ratio of 3 : 1 is obtained by the sol–gel method from titanium(IV) butoxide at a temperature below 100°C. X-ray diffraction, transmission electron microscopy, and Raman spectroscopy are used to show that the size of anatase particles is about 6 nm, and brookite particles consist of a crystal core, 4 nm in diameter, surrounded by an amorphous shell. Compared with the commercial Degussa P25 photocatalyst, which consists of the anatase and rutile phases in the same 3 : 1 ratio, the resulting TiO2 exhibits an increased photoactivity in hydroquinone oxidation. Quantum chemical modeling of anatase and brookite surfaces as well as their interface does not reveal the specific features of their electronic structure. This fact is indicative of the amorphous phase as an active participant in the transfer of charge carriers in the photocatalytic process.

The h-BN microcrystalline powder with carbon and oxygen impurities have been studied at 83 and 296 K using Raman and photoluminescence (PL) spectroscopies. The observed blue shift of Raman peaks with temperature decreasing have been discussed. Two series of phonon replicas in PL emission spectra with a zero-phonon line at 4.08 eV have been registered under 4.28 eV excitation. The energy levels model of the impurity (CN-ON)-complex responsible for observe luminescence was proposed. It was shown that the optically active center retains its electroneutrality in the processes of radiative recombination under subband (in 4.28 eV) or band-to-band excitation. Possible mechanisms of electron-phonon scattering and phonon replicas forming under subband excitation of (CN-ON)-complex were analyzed. It was substantiated that at 83 K the longitudinal optical (ℏωLO = 174 meV) and transverse acoustic (ℏωTA = 60 meV) phonons at the middle points of high symmetry in the first Brillouin zone participate in the processes of intravalley (M- and Κ-scattering) and intervalley (Κ → Μ)-scattering, respectively.

Structural reconstitution upon dry thermal annealing of mildly to strongly radiation-damaged, gem-quality zircon from Sri Lanka has been studied by single-crystal X-ray diffraction and Raman spectroscopy. Results of structure refinement of a strongly radiation-damaged zircon (sample GZ5, calculated alpha dose ~4 × 1018 g−1) indicate the existence of an interstitial oxygen site that is sparsely occupied (about 4% of all O atoms). Annealing of this sample at Ta (annealing temperature) = 700 °C has resulted in nearly complete recrystallization of its amorphous volume fraction and significant decrease in the occupation of O-interstitial sites. For all samples studied, annealing up to Ta ≤ 650–700 °C is characterised by preferred recovery of Raman shifts (compared to Raman FWHMs; full width at half band maximum) and extensive contraction of the unit-cell volume, in particular along unit-cell dimension a. This low-T annealing is dominated by epitaxial growth of the crystalline volume fraction at the expense of the amorphous volume fraction, and general recovery of low-energy defects. During annealing at Ta = 700–1400 °C there is preferred recovery of Raman FWHMs (compared to Raman shifts) and only mild unit-cell contraction. High-T annealing is dominated by the recovery of high-energy defects such as recombination of cation Frenkel pairs. Here, unit-cell parameter a shows a remarkable behaviour (namely, mild re-increase at Ta = 700–1150 °C and mild final shrinking at Ta = 1000–1400 °C), which is attributed to enhanced contortion of ZrO8 polyhedrons due to cation repulsion. The combined data set of Raman band and unit-cell parameter presented herein will help analysts to assign Raman spectra of annealed unknowns to certain recovery stages.

Core-level and valence-band X-ray photoelectron spectroscopy was employed to study the dose-dependent radiation effects in the short-range order and the electronic structure of natural U, Th-bearing zircon near-surface layers. Single crystals from different localities (Ratanakiri, Cambodia; Mud Tank, Australia; Highlands, Sri Lanka) exhibiting wide variations in the accumulated radiation dose D≈(0 ÷ 9.2)·1018 α-decays/g was investigated. The dose values obtained by electron probe microanalysis and Raman micro-spectroscopy were used to correlate the samples with the two percolation transitions (p1, p2) in the amorphous-crystalline structure of damaged zircon. The dose-dependent variations in Eb (530.9–531.3, 101.7–102.4, 182.8- 183.3 eV) and FWHM (1.32–2.57, 1.47–1.77, 1.16 -1.55 eV) of the O1s, Si2p, and Zr3d5/2 core levels, respectively, were attributed to changes in the ensemble of non-equivalent short-range order structures. An increase in the dose resulted in the complication of the oxygen sublattice, with the following nearest environments of O atoms: (1) O (Si, [8]Zr, [8]Zr), Eb = 530.8–531.2 eV, the amount of > ~3.5 apfu (at D p2). For the first time, under an increase in the radiation dose, the oppositely directed changes in the effective charges of Si and Zr cations were detected in damaged zircon. This phenomenon was assigned to an increase in the content of the short-range order fragments characteristic of pure oxides SiO2 (namely, Si-O-Si) and ZrO2 (namely, [7]Zr) as well as to the influence of the anions O (Si, Si, [8]Zr), and the assignment was independently confirmed by the valence band analysis. The sequence of transformations in the Si-O and Zr-O sublattices was shown to be not concurrent: a partial polymerization of SiO4 tetrahedra occurs mainly at low and medium doses (D p2) in the amorphous fraction.

IntroductionShock-induced changes in planetary materials related to impacts or planetary collisions are known to be capable of altering their optical properties. One such example is observed in ordinary chondrite meteorites. The highly shocked silicate-rich ordinary chondrite material is optically darkened and its typical S-complex-like asteroid spectrum is altered toward a darker, featureless spectrum resembling the C/X complex asteroids. Thus, one can hypothesize that a significant portion of the ordinary chondrite material may be hidden within the observed C/X asteroid population.The exact pressure-temperature conditions of the shock-induced darkening are, however, not well constrained and due to this gap in knowledge, it is not possible to correctly assess the significance of the shock darkening within the asteroid population. In order to address this shortcoming, we experimentally investigate the gradual changes in the chondrite material optical properties together with the associated mineral and textural features as a function of the shock pressure. For this purpose, we use a Chelyabinsk meteorite (LL5 chondrite), which is subjected to a spherical shock experiment. The spherical shock experiment geometry allows for a gradual increase in the shock pressure within a single spherically shaped sample from 15 GPa at its rim toward hundreds of gigapascals in the center.ResultsFour distinct zones were observed with an increasing shock load (Fig. 1). We number the zones in the direction of increasing shock from the outside toward the center as zones I–IV The optical changes in zone I are minimal up to ~50 GPa. In the region of ~50–60 GPa corresponding to zone II, shock darkening occurs due to the troilite melt infusion into silicates. This process abruptly ceases at pressures of ~60 GPa in zone III due to an onset of silicate melting and immiscibility of troilite and silicate melts. Silicate melt coats residual silicate grains and prevents troilite from further penetration into cracks. At pressures higher than ~150 GPa (zone IV), complete recrystallization occurs and is associated with a second-stage shock darkening due to fine troilite-metal eutectic grains.The order of the spectral curves in the UV-VIS-NIR (ultraviolet – visible – near-infrared) region follows the visual brightness in which zone I is the brightest, followed by zones III and II, and zone IV is the darkest one (Fig. 2). The MIR reflectance (Fig. 3) follows the same albedo order as UV-VIS-NIR up to the primary Christiansen feature at 8.7 µm. At higher wavelengths in the Si-O reststrahlen bands region, the reflectance order changes with zones II and III, which are brighter than zones I and IV. The comparison of the powdered sample spectra to the one obtained from the rough saw-cut surface reveals the following trends. The overall reflectance of the powdered sample is an order of magnitude lower compared to the rough surface one. The reststrahlen bands in both samples show similar positions at approximately 9.1, 9.5–9.6, 10.3, 10.8, 11.3, and 11.8–12 µm. They are dominated by olivine with possible presence of orthopyroxene. The amplitudes of the reststrahlen bands are higher in the rough surface sample. The transparency feature at 12.7 µm is only observed in the powdered sample. The primary Christiansen feature at 8.7 µm is more pronounced in the powdered sample, while the secondary one at 15.6 µm is of a low amplitude in both samples.ConclusionsThe important finding is the presence of the two distinct shock darkening mechanisms in ordinary chondrite material with characteristic material fabric and distinct pressure regions. These two regions are separated by a pressure interval where no darkening occurs. Thus, the volume of the darkened material produced during asteroid collisions may be somewhat lower than assumed from a continuous darkening process. While the darkening mainly affects the UV-VIS-NIR region and 1 and 2-µm silicate absorption bands, it does not significantly affect the silicate spectral features in the MIR region. These are more affected by material roughness. MIR observations have the potential to identify darkened ordinary chondrite material with an otherwise featureless UV-VIS-NIR spectrum.

Received: 24.12.2019. Accepted: 06.03.2020. Published: 31.03.2020. Analysis of platinum group elements (PGE) extracted from various catalysts used in the car, petroleum and chemical industries requires use of microanalytical methods. PGE content in the platinum powder concentrates K176 and K177 was studied by SEM-EDS. The content of main elements was determined using analytical lines Fe Kα1, Si Kα1, Sn Lα1, Pt Lα1, Re Lα1. The obtained data for the chemical composition are in good agreement with the result obtained by X‑ray fluorescence analysis and ICP-MS method. Powdered platinum concentrates are considered to be ferrosilicide (FeSi), where PGE are localized at the phase boundaries and in separate patches of the K176 sample, or distributed over the volume of particles in the K177 sample. This work was supported by the theme of state agreement of IGG UB RAS (theme No. АААА-А19‑119071090011‑6).

Refractory forsterite-rich inclusions are a common component for different classes of chondrites. They belong to one of the first mineral formations of the solar system. Forsterite is characterized by low ferruginosity (Fa 0.2–2.0), enrichment with refractory lithophilic elements (RLE), in particular CaO 0.5–1.0%, \({\text{Al}}_{ 2} {\text{O}}_{ 3}\) up to 0.3%, and at the same time a sharp deficit of MnO. In some refractory forsterite-rich inclusions, a rim is observed consisting of enstatite with a thickness of 5–200 µm. The composition of the enstatite is \({\text{SiO}}_{ 2}\) (58.545 wt%), \({\text{TiO}}_{ 2}\) (0.24 wt%), \({\text{Al}}_{ 2} {\text{O}}_{ 3}\) (1.04 wt%), \({\text{Cr}}_{ 2} {\text{O}}_{ 3}\) (0.55 wt%), FeO (1.06 wt%), MgO (37.95 wt%), and CaO (0.5 wt%). The article presents the first results of studying enstatite rims of the refractory forsterite-rich inclusions from the Northwest Africa 11781 carbonaceous chondrite using electron backscatter diffraction (EBSD). As a result of the mapping, it has been established that each of the two grains of refractory forsterite is overgrown with a whole individual enstatite grain. The curvature of enstatite individuals and their disorientation up to 40o is observed along the rim.

We report the results of the complex study of the bulk interior of Bursa L6 ordinary chondrite using optical microscopy, scanning electron microscopy with energy dispersive spectroscopy, electron microprobe analysis (EMPA), X-ray diffraction (XRD), magnetization measurements, and Mossbauer spectroscopy. The main and minor iron-bearing phases and their chemical compositions were determined by these techniques. The detected iron-bearing phases in the bulk interior of Bursa L6 are the following: olivine; orthopyroxene; Ca-rich clinopyroxene; troilite; chromite; hercynite; ilmenite; the alpha(2)-Fe(Ni, Co), alpha-Fe(Ni, Co), and gamma-Fe(Ni, Co) phases; and ferrihydrite resulting from meteorite terrestrial weathering. Using the EMPA, the values of fayalite and ferrosilite were obtained as similar to 25.2% and similar to 21.4%, respectively. The unit cell parameters for silicate crystals were determined from XRD, then the Fe2+ and Mg2+ occupations of the M1 and M2 sites in these crystals were estimated. Further calculations of the ratios of the Fe2+ occupancies in the M1 and M2 sites in olivine and orthopyroxene based on XRD and Mossbauer spectroscopy appeared to be in a good agreement. The temperatures of equilibrium cation distributions for olivine and orthopyroxene obtained from these techniques are consistent: 623 K (XRD) and 625 K (Mossbauer spectroscopy) for olivine and 1138 K (XRD) and 1122 K (Mossbauer spectroscopy) for orthopyroxene., Ministry of Science and Higher Education of the Russian Federation [FEUZ-2020-0060, AAAA-A18-118053090045-8, AAAA-A19-119071090011-6]; Act 211 of the Government of the Russian Federation [02.A03.21.0006]; Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [MFAG/113F035]; Ege University Scientific Research Projects Coordination UnitEge University [17-FEN-050]; Hungarian Ministry of Human Capacities [783-3/2018/FEKUTSRAT], The authors are grateful to G.A. Yakovlev (Ural Federal University, Ekaterinburg, Russian Federation) for the help with scanning electron microscopy. This work was supported by the Ministry of Science and Higher Education of the Russian Federation, project No FEUZ-2020-0060 and by Act 211 of the Government of the Russian Federation, contract No 02.A03.21.0006. O.U. was supported by the Scientific and Technological Research Council of Turkey (TUBITAK), project No MFAG/113F035 and by the Ege University Scientific Research Projects Coordination Unit, project No 17-FEN-050. D.A.Z. and A.A.M. were supported by the Ministry of Science and Higher Education of the Russian Federation, projects No AAAA-A18-118053090045-8 (D.A.Z.) and No AAAA-A19-119071090011-6 (D.A.Z. and A.A.M.). on behalf of two of us (~ A.Sz. and Z.D.), this work was completed in the ELTE Excellence Programme (783-3/2018/FEKUTSRAT) supported by the Hungarian Ministry of Human Capacities. This work was carried out within the Agreement of Cooperation between the Ural Federal University (Ekaterinburg) and the E_otv_os Lor~and University (Budapest).

Modern microbeam analytical instruments allow obtaining images and maps of heterogeneous minerals and synthetic materials in various signals with micron and submicron spatial resolution. Joint image analysis of several images allows getting more complete information about the sample that one image, but this joint analysis is usually subjective and is carried out at a qualitative level. Current study is devoted to the development of a joint quantitative analysis of images (JPD method) and its software implementation with the aim of more efficiently extracting information about the features of the internal texture and finding the correlation relationships of image characteristics with the physicochemical properties of samples that are in demand for settle issues of mineralogy and materials science.

A new XPS methodology to analyze the atomic and electronic structure of a wide-gap dielectric zircon has been developed. A high spectral resolution with the O1s-line width of 1.3 eV and volume (near surface) sensitivity have been achieved by using a spectrometer with a dual charge compensation system and monochromatic Al\(K_{\upalpha}\)-excitation as well as by the measurement (electron exit angle 90°, spot diameter 100 μm) and sample preparation (fresh cleavage) conditions. The possibility of analysing the structure of short-range order, in particular, diagnosing the formation of Si-O-Si and Si-OH fragments occurring in the bulk and/or surface layers of zircon under the influence of external (e.g., radiation, chemical) factors, is shown.

A series of sol-gel TiO2/CdS, TiO2 powders and coagulated CdS nanoparticles were studied by XRD, HRTEM and Raman spectroscopy to elucidate the effect of low-temperature gel aging time on visible photoluminescence (PL) emission of the TiO2/CdS composites. With an increase in aging time a content of amorphous titania and incorporated CdS nanoparticles decreases in composites. For all composites, visible PL emission includes bands attributed to surface oxygen vacancies and hydroxyl group of TiO2 nanocrystals, as well as yellow-green and red bands related to lattice defect states of CdS nanoparticles. It was found that gel aging time is a crucial parameter to influence visible PL emission in composites. This emission is suppressed with increasing aging time, and its evolution shows that healing of oxygen vacancy defects and hydroxyl group affect visible emission more significantly than improving crystallinity degree. The correlation between visible PL emission in TiO2/CdS and their visible-light photocatalytic activity was discussed. © 2020, ITMO University. All rights reserved. The research was carried out in accordance with the state assignment for ISSC UB RAS and financial support from ISSC UB RAS (theme AAAA-A19-119031890025-9). TEM study was supported by RFBR (grant No. 20-02-00906). The authors are grateful to Dr. Kozhevnikova N. S. and Dr. Gorbunova T. I. for the provided samples TiO2/CdS and CdS.

The migration corridors of Bewick’s swan, which inhabits the Yamalo-Nenets Autonomous District, were identified in 2015–2017 using GPS-GMS transmitters. It was shown that even the individuals that inhabit the same region widely used different wintering sites. The birds that nest and molt in southern Yamal (Baydaratskaya Bay) were found to migrate through two corridors: the eastern corridor that leads to southeastern China and the western one that leads to the Caspian Sea, the Evros River delta, countries of Central and Middle Asia, and northwestern China. Fourteen key stopover sites were revealed. We explain the appearance of new Asian and European wintering sites by the general increase in the species’ numbers and believe that the decrease in the size of the Northern European population that has been observed since the mid-1990s is due to a loss of natural habitats. We have shown for the first time that the wintering range of Bewick’s swan with the revealed Asian wintering sites being taken into account is quite large. As the climate changes, some stopover sites can be used as wintering sites, which may lead to an even greater expansion of the wintering range of the species in the future.

This study based on the experience of treatment of 57 patients who previously were operated at the clinic for cancer of the stomach and esophagus. These patients had complications in the form of esophageal anastomotic leakage and esophageal anastomotic stricture. There were 9 patients with esophageal-gastric anastomotic leakage , 11 patients with esophageal - intestinal anastomotic leakage, 20 patients with a stricture of esophageal - gastric anastomosis, 17 patients with a stricture of esophageal - intestinal anastomosis. All the patients were undergone stenting of esophageal anastomosis. The results of using this method of treatment were estimated. Stenting of the esophagus with self-expandable stents with a coating is a method of choice for the treatment of patients with insolvency of esophageal anastomosis and avoids traumatic surgery, especially in weakened patients, as well as helps to save lives in patients with these severe complications. When scarring strictures of esophageal anastomosis, especially when other methods of treatment (boughing, balloon dilatation) fail, stenting is also a very effective minimally invasive method that can restore the passage of the gastrointestinal tract and improve the quality of life of the patient, as well as an alternative to traumatic surgery to correct stricture of esophageal anastomosis .

The questions of experimental design of the closed trauma of heart are considered in the article. Ultrastrukture and morphofunkcionale violations of cages of myocardium are certain, to the appropriate contusions damages of heart. In a conclusion underline, that characteristic violations in cardiomyocites are conditioned by the change of myofibrils and mytochondry presented, in particular, subsegmentarecjn tracture, appearance of stripes of reduction and nidal compression of myofibrils.

Представлен анализ наблюдений за 67 пострадавшими, госпитализированными в клинику Института общей и неотложной хирургии имени В. Т. Зайцева НАМН Украины по поводу закрытой травмы груди, в первые часы после травмы, а затем - в динамике в последующие сутки. По результатам исследования установлены достоверные изменения показателей электрокардиографии (ЭКГ), патогномоничные для контузионного повреждения сердца.

The U-Th-Pb isotope system in the accessory mineral zircon may be disturbed, as for instance by the secondary loss of radiogenic lead. The recognition of such alteration is crucial for the sound interpretation of geochronology results, in particular for chemical dating by means of an electron probe micro-analyser (EPMA). Here we present the example of high-U zircon samples from a granite pegmatite from the Aduiskii Massif, Middle Urals, Russia. The structural and chemical heterogeneity of samples was characterised by EPMA, including joint probability distribution (JPD) analysis of back-scattered electrons (BSE), cathodoluminescence (CL) and U M β images, and by Raman and photoluminescence (PL) spectroscopy. We found a high-U interior region (U up to 11.4 wt%) without any obvious indication of alteration. This domain has stoichiometric composition, and its Raman spectrum is similar to that of amorphous ZrSiO4. In addition, altered lower-U regions are present that are non-stoichiometric and contain non-formula elements such as Ca, Al, Fe, and water up to several wt%. Their Raman spectra yielded a band near 760–810 cm−1 which is not related to any ZrSiO4 vibration; we assign it tentatively to the symmetric stretching of (UO2)2+ groups. This assignment is supported by the observation of a fairly intense PL phenomenon whose spectral position and vibrational-coupling structure strongly indicates a uranyl-related emission. Altered zones were formed by both fluid-driven diffusion reaction and coupled dissolution-reprecipitation processes. The variation of BSE and CL intensities in amorphous high-U zircon is controlled by its chemical composition and the presence of water and uranyl groups. We have determined a weighted mean EPMA age of 246 ± 2 Ma, which agrees reasonably well with previous dating results for the Aduiskii Massif.

The ore specialization of carbonatite complexes of Urals-Timan region has been established: niobium and rare earth-niobium - for the Urals’ carbonatite complexes, the rare-earth - for carbonatites of Timan. The carbonatites of Il'menо-Vishnevogorsky miaskite-carbonatite complex (Urals) are a type of industrial niobium deposits (pyrochlore type of ores). The carbonatites of Baiksky ultrabasic complex (The Urals) are rare earth-niobium type deposits (monazite-aeschynite-columbite-pyrochlore type of ores). The carbonatites of Chetlassky complex (Middle Timan) are cerium type deposits of bastnesite carbonatites (with monazite-bastnesite type of ores). The picrite-lamprophire series of Chetlassky complex have diamond prospects. The ore specialization of the Urals and Timan carbonatite complexes are determined by their formational affiliation.

The analysis of the gas phase composition of fluid inclusions in quartz from Krasnoye gold deposit (Eastern Siberia) was carried out using Horiba LabRam HR800 Evolution Raman spectrometer. CO2 was found to be the major component of fluid inclusions in quartz; it is formed due to fluid-rock interaction during the destruction of host black shales. CO2 mol fraction (and CO2 density) in inclusions in quartz from the gold-bearing and barren vein were estimated as 96.9–98.6 and 88.3–98.0% mol (1.23–1.29 and 1.25–1.30 g/cm3), respectively. No differences in CO2 and N2 concentrations were found between the gold-bearing and barren quartz veins. The calculation results of the gas phase composition have been confirmed by gas chromatography. Based on our experience, study the composition of fluid inclusions which size is in the range 5–40 μm and located at the depth of about 100 μm from the surface of transparent minerals is promising when using HR800 Raman spectrometer.

We report results of the Raman measurements for ${\mathrm{SrRu}}_{2}{\mathrm{O}}_{6}$ having extraordinary high N\'eel temperature for a layered material. No additional phonon modes were detected at the temperature of magnetic transition thus excluding lowering of the symmetry in the magnetically ordered phase. An unusual increase in softening and damping of some phonons as the temperature approaches ${T}_{N}$ indicates the appearance of a continuum of interacting electronic excitations at $T\ensuremath{\ge}300\phantom{\rule{4.pt}{0ex}}\text{K}$. We also observe an intensive Raman response at 2050 ${\mathrm{cm}}^{\ensuremath{-}1}$. Analysis of the polarization dependence and comparison with available theoretical data shows that this peak likely originates from the transitions between molecular orbitals previously proposed to explain the magnetic properties of ${\mathrm{SrRu}}_{2}{\mathrm{O}}_{6}$. It can be explained by two magnon excitations only if the magnon bandwidth is $\ensuremath{\sim}140$ meV.

Oxidation state of iron in chromium spinel is an important indicator of the redox conditions of their formation and evolution. Mineral grains often heterogeneous in the Fe oxidation state, which is why the use of traditional bulk methods of chemical analysis and Mossbauer spectroscopy is not correct. Local methods for measuring Fe3+/Fe2+ in iron oxide minerals are highly demanded. This work is devoted to the application of X-ray electron microanalyzer for the estimation of Fe oxidation state in iron oxide minerals, including chromium spinel, by analyzing the shape of X-ray emission spectra FeLα,β. The study was carried out on chromium spinels from Ural ultramafic massifs and reference laboratory samples of wustite, hematite, magnenite, trevolite, ilmenite, and chromite. The values of the oxidation state of iron Fe3 +/Fe in chromium spinels were certified according to Mossbauer data and ranges from 8 to 42.3%. To quantify the shape of the X-ray emission spectra FeLα,β two spectral processing algorithms were applied: a decomposition of spectra into Voigt lines, followed by finding the intensity ratio of the FeLα/Lβ lines, and the method of central moments. The correlation of central moments of Fe Lα,β with Fe concentration, the asymmetry of Fe Lα with the Fe oxidation state of iron-oxide minerals were found.

Zircon was synthesized by the sol-gel route and subjected to sequential heat treatment. X-ray powder diffraction showed that single-phase zircon was obtained. The impurity content and microstructure of the obtained ceramic were studied by the mass spectrometry and scanning electron microscopy. The contents of Hf ~0.8 ​wt% and Al ~0.2 ​wt% are prevailing, while the presence of other impurity elements does not exceed 0.06 ​wt%. The photo- and cathodoluminescence data indicate the presence of structural and impurity defects. The instability of structural defects during high-temperature annealing was observed. The average value FWHM of the Raman B1g(4) band of asymmetric stretching vibrations of SiO4 tetrahedra lies in the range 2.55–3.15 ​cm-1, which slightly exceeds the minimum value ~1.8–2.0 cm-1 in the spectra of perfect single crystals. The zircon synthesized can be used as a reference sample for spectroscopic studies in mineralogy.

Using techniques of microprobe analysis and Raman microspectroscopy, a study of the composition, structure, and age of high-uranium zircon from the Sharatash intrusion pegmatite was performed. The presence of a number of zones in crystals having different physicochemical characteristics has been revealed. The Id-e zones affected by a radiation dose of (30–130) × 1018 α-dec/g were completely amorphized, and their chemical isochron age was estimated at 311.4 ± 7.1 Ma: this is interpreted as the time of zircon formation in the pegmatite. The age of uraninite coupled with zircon is 317.1 ± 2.3 Ma. These dating results clarify the formation time of the final phase (pegmatite) of the Shartash intrusion and determine the upper age limit of hydrothermal gold mineralization (Berezovsk deposit) associated with the granite massif.

The preferred local environment of CdS nanoparticles within the sol-gel synthesized TiO2/CdS composites with a multiphase titania matrix was unveiled in detail. Evolution of the environment was traced along the full path of the gel aging. HRTEM showed that the CdS particles are typically surrounded by amorphous titania within the composites based on complex amorphous-rich anatase/brookite matrix, while the brookite crystallites are more preferable in the vicinity of CdS within the composites with anatase/brookite matrix. Transformation path from amorphous into crystalline titania phases in the vicinity of CdS nanoparticles is seemingly regulated by the cohesion between titania and CdS, which degree has been estimated on the models of "core-shell" CdS@TiO2 composite nanoparticles as a function of titania polymorphism. MD simulations demonstrate that the thermodynamic stability and the interface interaction decrease in the series of amorphous titania, nanocrystalline brookite, nanocrystalline anatase. The structural analysis reveals that, in contrast to anatase, the enhanced CdS||TiO2 interface interaction in the case of brookite is due to a genuinely more distorted lattice of brookite, hence, due to its better match to a foreign irregular interface. It is suggested that the TiO2/CdS composites with the prevalent brookite surrounding of CdS nanoparticles can exhibit enhanced photocatalytic activity compared to the composites with a random anatase/brookite surrounding of CdS nanoparticles, since brookite has a moderate depth of electron traps.

High-entropy alloys forming non-cubic crystal structures are intriguing systems for both scientific and functional viewpoints. Hexagonal-structured HEAs are among them. In this work, we have fabricated a single-phase hexagonal close-packed phase in ScTiZrHf system. To verify its structural stability, we anneal the alloy samples at 973 K for a long time from 15 up to 140 h. Structural analysis reveals that the HEA retains its single-phase structure after the thermal treatment. To characterize the material, we examine its electron-transport and magnetic properties over a wide temperature range. The alloy electrical resistivity has purely metallic temperature dependence, while its absolute values are rather high. The thermal conductivity in this material is very low. The analysis of the transport properties reveals a noticeable lattice contribution ( ≈ 50% ) in total thermal conductivity probably caused by a strongly defected crystal structure. The alloy magnetization demonstrates complicated temperature dependence, which is well described by a superposition of Curie–Weiss and valence-electron contributions. Based on this suggestion, we fit experimental magnetization data and extract the electron density of states (DOS) at the Fermi level as ≈ 1 e V − 1 . To address the properties of interatomic interaction in the system, we perform ab-initio molecular dynamics simulations of the liquid phase. The data obtained indicate unambiguously the absence of strong chemical interaction between alloy components as well as the nearly additive character of the liquid mixture that supports the results obtained experimentally.

Most known single-phase high-entropy alloys (HEAs) are metastable materials that decompose after long annealing into a mixture of two or more solid solutions. Besides simple FCC and BCC phases, the formation of σ-phase, which essentially affects mechanical properties, is often observed in HEAs. Moreover, long-time annealings affect essentially the microstructure of HEAs. Here we address these issues for AlCoCrFeNiMn high-entropy alloy and compare results with those for AlCoCrFeNi one. Performing long-time isothermal (up to 500 h) annealing at different temperatures, we estimate thermal stability region of σ-phase as 820 − 1230 K. Below 820 K, the equilibrium structure of the alloy is a mixture of BCC and FCC phases. Annealed AlCoCrFeNiMn alloy demonstrates a coarse-grained microstructure with characteristic size of phase areas of 20–30 μm, which are by the order of magnitude larger than for AlCoCrFeNi alloy. Such microstructure leads to unusual behaviour of transport properties, which is not typical for multicomponent systems. In particular, residual Lorenz number in AlCoCrFeNiMn alloy is very close to 1 which indicates pure electronic character of its thermal conductivity. We also observe that AlCoCrFeNiMn is an ultra-soft ferromagnetic material whose coercive force does not exceed 5 Oe.

This study based on the experience of treatment of 57 patients who previously were operated at the clinic for cancer of the stomach and esophagus. These patients had complications in the form of esophageal anastomotic leakage and esophageal anastomotic stricture. There were 9 patients with esophageal-gastric anastomotic leakage , 11 patients with esophageal - intestinal anastomotic leakage, 20 patients with a stricture of esophageal - gastric anastomosis, 17 patients with a stricture of esophageal - intestinal anastomosis. All the patients were undergone stenting of esophageal anastomosis. The results of using this method of treatment were estimated. Stenting of the esophagus with self-expandable stents with a coating is a method of choice for the treatment of patients with insolvency of esophageal anastomosis and avoids traumatic surgery, especially in weakened patients, as well as helps to save lives in patients with these severe complications. When scarring strictures of esophageal anastomosis, especially when other methods of treatment (boughing, balloon dilatation) fail, stenting is also a very effective minimally invasive method that can restore the passage of the gastrointestinal tract and improve the quality of life of the patient, as well as an alternative to traumatic surgery to correct stricture of esophageal anastomosis.

The results of investigations of natural iron-chromium spinels of variable composition Fe2+(Cr2-xFex3+)O4 of the chromite-bearing Klyuchevskoi massif (Middle Urals), which are the main carriers of the magnetization of rocks are presented. Substantial changes in the composition and in magnetic structure of accessory chrome-spinels scattered in the host rock are established, unlike the almost unaltered ore-forming chrome-spinels, under the influence of secondary geological processes. To establish the connection between the chrome-spinel changes at the microlevel and features of the geomagnetic field anomalies created by this carrier of magnetization of rocks, it is carried out a complex of investigations of Fe-Cr-spinels (thermomagnetic analysis over the temperature range (4÷1000) K; magnetic resonance (MR) spectroscopy and magnetic force microscopy (MFM) in addition to magnetomineralogical studies). As a result, in the relict areas of grains of the accessory chrome-spinels were first discovered the magnetic clusters (superparamagnetic phases) in the form of single or groups of 2 – 3 magnetic dipoles of tens nanometers in size, or in the form of chain-like structures of magnetic dipoles/single domains.

High-uranium natural zircon with signs of hydrothermal (up to 300°C) treatment is studied via transmission electron microscopy, Raman spectroscopy, electron probe microanalysis, and local energy-dispersive analysis performed in situ with a transmission electron microscope. Uranium-based phases are not found in the regions with uranium concentrations of up to 10 wt % that exceed considerably the limit of solubility in synthetic zirconium silicate. Uranium is dissolved in a heterogeneous matrix that is formed as a result of the decomposition of radiation-damaged (a dose of 1017 α-decays/mg) zircon under hydrothermal influence. The matrix incorporates amorphous partially hydrated silicon oxide and nanocrystalline cubic (Zr,Hf)1-y MeyO2 stabilized with metal Me impurities (Y, Ca, Al, Fe; y ≈ 0.04). Cubic zirconium oxide is regarded as the preferred phase for uranium localization, while the total impurity concentration is ~0.13.

Chromite mineralization in metamorphosed dunites from the southern Klyuchevskoy dunite-harzburgite ultramafic complex (Central Urals) has been investigated using geomagnetic surveys along with laboratory studies of ore-forming and accessory spinels of the same genetic type. Magnetization in the study area is carried mainly by accessory Fe-Cr-spinel of a variable Fe2+(Cr2-xFex3+)O4 composition. Metamorphism caused changes in element contents and in both crystal and magnetic structure of the primary nonmagnetic accessory spinel, unlike the almost fresh ore-forming spinel. Thus, ore bodies stand against their host rocks, which is a prerequisite for the use of geomagnetic surveys for exploration of podiform chromite deposits in dunite-harzburgite complexes. Ground magnetic surveys at a test site composed of faulted rocks bearing disseminated chromite mineralization in metamorphosed dunites resolved a chromite ore zone and a fault block boundary showing up as geomagnetic anomalies. Laboratory studies using high technologies (thermomagnetic analysis at 4 to 1000 K, as well as magnetic resonance and magnetic force spectroscopy) revealed, for the first time, magnetic clusters (superparamagnetic phases) in primary nonmagnetic accessory spinel, which are responsible for the magnetic properties of the host rocks. Microscale variations in Cr-spinel correlate with the geomagnetic anomalies recorded by field surveys at the test site. © 2015, V.S. Sobolev IGM, Siberian Branch of the RAS. Published by Elsevier B.V. All rights reserved.

Ilmenite crystals incorporated into epidote phenocrysts of porphyry dikes contain up to 8.8 wt % ZnO and 20 wt % MnO. These crystals, less than 50 μm in size, are associated with rutile, pyrite, pyrrhotite inclusions and are characterized by nonuniform Zn distribution. Ilmenite microphenocrysts 100–200 μm in size that occur in the muscovite-epidote-quartz-feldspar groundmass contain up to 2.4 wt % ZnO and 10–20 wt % MnO. It is suggested that the formation of Mn- and Zn-bearing ilmenite is related to impact of hydrous oxidized melt on the sulfide-bearing crustal rocks, giving rise to sphalerite decomposition.

A new quantitative approach on the basis of joint probability distribution (JPD) analysis of BSE- and CL-images is proposed for studies of the zoning of polygenic (polychronous) grains of zircon. It was shown for the example of zircon of the Mugodzhar metamorphic rocks (South Ural) that a series of zones might be distinguished in the grains of high chemical (structural) heterogeneity. Zones Ia and Ib belong to the fragments of crystalline and radiation-damaged zircon, respectively. Zone II corresponds to the primarily disordered areas (the “genetically metamict” zones) of high concentrations of the impurities of Y, P, REE, U, Hf, etc. The Ia-Ic trend is related to the process of autoradiation metamictization. Based on the data on oxygen content, the declinations of zircon composition from the stoichiometry and the hydration effects were considered.

Structure and thermodynamic properties of zircon, coffinite, and zircon-coffinite solid solutions were subject to semiempirical atomistic simulation on the assumption of compositional disordering of mixed crystals: (Zr1 − x , U x )SiO4, where x = 0.02, 0.05, 0.08, 0.11, 0.14, 0.28, 0.50, 0.72, and 0.86. The solid solutions significantly depart from the Vegard and Retgers laws. The (Zr1 − x , U x )SiO4 mixed crystal structure is characterized by anisotropic expansion (largely in the a and b directions) under growth in x related to anisotropy of structural relaxation degree of the cation-oxygen interatomic spacing in the (Zr, U)O8 polyhedron. Increase in x parameters is accompanied by increase in average size of cation-oxygen polyhedrons and silica-oxygen tetrahedrons and by growth of interatomic spacing dispersion; maximum dispersion values are observed at x = 0.5–0.6. The distortions in local structures of ZrO8 and UO8 dodecahedrons and silica-oxygen tetrahedrons in the solid solution were analyzed on the basis of calculated functions of interatomic distance distribution. The obtained results demonstrate the possibility to assess numerically the structural (geometrical) disordering degree of the compositionally disordered solid solution depending on its composition. The calculated thermodynamic characteristics of solid solutions forecast the following solubility range limits: 2 mol % USiO4 in zircon and 5 mol % ZrSiO4 in coffinite under ∼1750 K.

The microstructure and magnetic properties of accessory Fe–Cr-spinels from the Kytlym massif of the Urals platinum-bearing belt were studied. Atypical Fe–Cr-spinels in the form of magnetic microareas in grains of primary nonmagnetic Fe–Cr-spinel have been revealed for the first time in the bed dunites of the Kytlym multiphase concentrically zoned massif, North Urals. These spinels are responsible for the magnetic properties of the dunites. It has been established that the microareas are separations in solid solution Fe2+(Cr2–xFex3+)O4, which are enriched in Fe3+ and are probably an intermediate product of the transformation of primary accessory Fe-Cr-spinel during the formation of the dunite massif. These are magnetic microphases with particular chemical composition, cation distribution, and corresponding reversed crystal lattice, which determine the main magnetic properties of the microarea: the magnitude and direction of magnetization vector and Curie temperature. The formation of this earlier unknown type of magnetic Fe–Cr-spinel is probably conjugate with the formation and concentration of PGE mineralization in the bed dunites of the Kytlym platinum-bearing massif. The presence of such magnetization carriers in rocks and ores must be taken into account in geophysical research at the Urals chromite and platinum–chromite deposits.

Epidote-bearing porphyritic dikes (whole rock analysis: SiO2 = 55–65 wt. %, MgO 17 wt. %, Na2O + K2O = 5.7–9.4 wt. %) situated in the continental margin zone, the Middle Urals, Russian Federation have been dated using SHRIMP U-Pb zircon techniques and give a Middle Devonian age of 388 ± 2 Ma and 389 ± 6 Ma. The porphyries contain phenocrysts of magmatic epidote (Ps = 17–25 %), Ca- and Mn-rich (CaO >9 wt. %; MnO >6 wt. %) almandine garnet, Al-rich (Al2O3 = 12–16 wt. %) amphibole, titanite, plagioclase, biotite, muscovite, apatite, and quartz. 60 to 70 % groundmass of the porphyritic dikes consists of fine-grained albite, quartz, and K-feldspar. A variety of thermobarometric estimations, plus comparison with published experimental data indicate that the phenocryst assemblage was stable between 5 and 11 kbar and 690 to 800 °C. Oxygen fugacity was close to or greater than logfo2 = Ni-NiO + 1. Later stage formation of the quartz-feldspar groundmass took place at hypabyssal conditions, corresponding to 1 to 2 kbar and 660 to 690 °C. The porphyritic dikes are metaluminous to slightly peraluminous (ACNK = 0.7–1.17). They are enriched in REE and depleted Nb and Ti. They show features typical of subduction-related magmas. Chemical composition and isotopic ratios of 86Sr/87Sri = 0.709–0.720 suggest that both mantle- and deep crustal-derived materials were involved in their petrogenesis.