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Waste steel slag is a major source of environmental pollution within the metallurgical industries. Metallurgical slags like blast furnace slag, ferroalloy slag, converter slag and copper slag are produced as by-products in metallurgical processes. During the production of steel, one ton of slag waste is generated per every three tons of stainless steel produced. In order to reuse waste steel slag, discharged at high temperature range (1250-1650 °C) and cooled in water, which is named as granulated slag, three different slag samples were analyzed. In this study, the solid particle diameter, size distribution, humidity, elemental composition and surface morphology of the slag samples were investigated. The elemental analysis of granulated slags was determined by X-Ray Fluorescence (XRF) analytical equipment and the microscopic morphology of the samples was characterized with a scanning electron microscope - SEM (Fei Q 200). From the particle size analysis, the results show for all three samples that the predominant granulation is about 71 μm, and the average granulation is between 1.25 mm and 71 μm. Also, from the elemental chemical analysis the results show that the predominant chemical elements are iron, manganese, barium and chromium. [ABSTRACT FROM AUTHOR]

The main purpose of the research is investigating approaches of nanostructural perovskite obtaining. We used wide known methods, which used for studying microstructure and electronics properties such as atom-force and scanning electron microscope, X-ray diffraction method. Halide perovskites have emerged recently as promising materials for many applications in photovoltaics and optoelectronics. Recent studies of their optical properties suggest many novel opportunities for a design of advanced nanophotonic devices due to low-cost fabrication, high values of the refractive index, existence of excitons at room temperatures, broadband bandgap tunability, high optical gain and nonlinear response, as well as simplicity of their integration with other types of structures. This paper provides an overview of the recent progress in the study of optical effects originating from structured perovskites, including their potential applications. Also, based on perovskites, LEDs can be created due to their excellent luminescent properties. Perovskite-based LEDs can be made in the long wavelength range, in total visible radiation, in this spectrum it will almost not depend on the size of the elements, but only on the properties of the material itself. The ability of perovskites to absorb light is also used to make effective photodetectors. This class of materials revolutionized the field of photovoltaics, where on the basis of it the efficiency level of 23.3% has already been achieved, which approaches much more expensive analogs based on silicon. Also, based on perovskites, LEDs can be created due to their excellent luminescent properties. Perovskite-based LEDs can be made in the wavelength range of all visible radiation, and the spectrum will almost not depend on the size of the element, but only on the properties of the material itself. The ability of perovskites to absorb light is also used to make effective photodetectors. It has recently become clear that from the point of view of nanophotonics, perovskite is of considerable interest. Perovskite-based nanostructures are cheap to produce, they have high refractive indices, which allows localizing light and controlling it at the nanoscale, and excitons are also observed at room temperature. In addition, this material is conveniently combined with other types of nanostructures to obtain new optical effects. The optical characteristics can simply be varied by changing the X - anion, due to the dependence on the valence and conduction bands of APbX3, lead halide materials with ionic binding strength decreasing in the sequence Pb-Cl

The main purpose of the research is investigating approaches of nanostructural perovskite obtaining. We used wide known methods, which used for studying microstructure and electronics properties such as atom-force and scanning electron microscope, X-ray diffraction method. The major findings of the research are following: recent developments in the physics of high-index resonant dielectric nanostructures suggest alternative mechanisms for subwavelength light control driven by Mie resonances with strong magnetic response that can be employed for a design of novel optical metasurfaces. Here we demonstrate metasurfaces based on nanoimprinted perovskite films optimized by alloying the organic cation part of perovskites. We reveal that such metasurfaces can exhibit a significant enhancement of both linear and nonlinear photoluminescence (up to 70 times) combined with advanced stability. Our results suggest a cost-effective approach based on nanoimprint lithography and combined with simple chemical reactions for creating a new generation of functional metasurfaces which may pave a way towards highly efficient planar optoelectronic metadevices. this class of materials revolutionized the field of photovoltaics, where on the basis of it the efficiency level of 23.3% has already been achieved, which approaches much more expensive analogs based on silicon. Also, based on perovskites, light-emitting diodes can be created due to their excellent luminescent properties. Perovskite-based light-emitting diodes can be made in the wavelength range of all visible radiation, and the spectrum will almost not depend on the size of the element, but only on the properties of the material itself. The ability of perovskites to absorb light is also used to make effective photodetectors. [ABSTRACT FROM AUTHOR]

The dike rocks under study are localized in Mesozoic (T3-J2) clastic rocks in the western part of Verkhoyansk-Kolyma fold area. Studying the nature of the dikes and geodynamic setting of their formation is of great interest now in view of the controversy surrounding their assignment to definite magmatic complexes of the VerkhoyanskKolyma fold area and the uncertain origin of mineralization in the Yana-Kolyma gold belt. Major elements were determined using the silicate analysis of magmatic rocks. The mineral compositions of dike rocks were studied using a Tescan MIRA 3 LMU scanning electron microscope. Studies of REE and other trace elements were performed with the use of mass spectrometers – quadrupolar Agilent7500ce (Japan) and highresolution Element2 (Germany). Their petrologic compositions vary widely including basanite, trachybasalt, andesite, trachyandesite, dacite and granodiorite. The rocks are spatially associated with gold mineralization of the Yana-Kolyma gold belt. Intense secondary alteration of the dikes includes carbonatization, chloritization, pelitization, sericitization, saussuritization, and epidotization. The SiO2 content in the sampled rocks varies from 46.8 to 70.5 wt. %, while the total amount of Na2O+K2O ranges from 2.69 to 7.59 wt. %. The dike rocks belong to the low- and high-K calc-alkaline and the shoshonite magmatic series. They exhibit a uniform REE distribution pattern intermediate between those of OIB and E-MORB. The flat HREE trend is close to that of MORB. The Eu anomaly is absent (0.9-1.0). Positive Ba, K and negative Ti, Ta, and Nb anomalies are observed. Trace element trends are much like those established for mafic rocks from dikes at the Malo-Tarynskoe and Tin-Yuryuete gold deposits in the western part of the Verkhoyansk-Kolyma fold area. The dikes could have formed from mixed enriched and depleted mantle sources, possibly with the involvement of a subduction-related component. The dike rocks under study are localized in Mesozoic (T3-J2) clastic rocks in the western part of Verkhoyansk-Kolyma fold area. Studying the nature of the dikes and geodynamic setting of their formation is of great interest now in view of the controversy surrounding their assignment to definite magmatic complexes of the VerkhoyanskKolyma fold area and the uncertain origin of mineralization in the Yana-Kolyma gold belt. Major elements were determined using the silicate analysis of magmatic rocks. The mineral compositions of dike rocks were studied using a Tescan MIRA 3 LMU scanning electron microscope. Studies of REE and other trace elements were performed with the use of mass spectrometers – quadrupolar Agilent7500ce (Japan) and highresolution Element2 (Germany). Their petrologic compositions vary widely including basanite, trachybasalt, andesite, trachyandesite, dacite and granodiorite. The rocks are spatially associated with gold mineralization of the Yana-Kolyma gold belt. Intense secondary alteration of the dikes includes carbonatization, chloritization, pelitization, sericitization, saussuritization, and epidotization. The SiO2 content in the sampled rocks varies from 46.8 to 70.5 wt. %, while the total amount of Na2O+K2O ranges from 2.69 to 7.59 wt. %. The dike rocks belong to the low- and high-K calc-alkaline and the shoshonite magmatic series. They exhibit a uniform REE distribution pattern intermediate between those of OIB and E-MORB. The flat HREE trend is close to that of MORB. The Eu anomaly is absent (0.9-1.0). Positive Ba, K and negative Ti, Ta, and Nb anomalies are observed. Trace element trends are much like those established for mafic rocks from dikes at the Malo-Tarynskoe and Tin-Yuryuete gold deposits in the western part of the Verkhoyansk-Kolyma fold area. The dikes could have formed from mixed enriched and depleted mantle sources, possibly with the involvement of a subduction-related component. [ABSTRACT FROM AUTHOR]

Wood protection is carried out in accordance with the requirements for the specific applications. It is commonly admitted to perform class 2 and 3 coatings for surface finish according to EN 335. The effect and interaction between wood mass and amorphous titanium dioxide are investigated in order to improve the quality of surface finish. Coatings with planar particles of titanium dioxide were used for dispersions applied on wooden surface in a transparent layer. The interaction between the wood surface and TiO2 was investigated with Fourier transform infrared spectroscopy (FTIR), which identifies spatially differentiated properties and effects. With the FTIR method, we can observe the delimitation of changes and the resolution of the material in a complicated wood structure. Changes of titanium dioxide layer binding properties to wood were compared to control sample; sample without exposure to artificial accelerated aging was compared to the exposed one. Aging of samples was performed according to EN 927- 6 - standard methodology for determining the quality and changes in the paint system exposed to accelerated artificial aging. The microscopic studies were performed with the scanning electron microscope (SEM). Changes of wooden cells triggered by UV radiation could be observed. [ABSTRACT FROM AUTHOR]

The Upper Devonian shales are predominantly carbonate, carbonate-siliceous thin-layer rocks with a high content of organic matter. Considered formation is widespread within the Volga-Ural and Timan-Pechora basins in the European part of Russia. Various estimations show that the hydrocarbon resources of the Upper Devonian shales range between hundreds of millions to billions of tons of oil. However, recovery of such hydrocarbons is significantly constrained due to the high heterogeneity and complex structure of rocks and its pore space. The paper presents the results of complex lithological studies of Upper Devonian shales based on core material from two wells located in the northern part of the Verkhnekamsk depression. Study includes data obtained with a scanning electron microscopy (SEM), X-ray structural analysis, optical microscopy, nuclear magnetic resonance (NMR) and Rock-Eval pyrolysis method. Analyzed rock samples mainly represent mixed carbonate-siliceous differences with a significant content of organic matter. A total of 11 lithotypes were identified and grouped by the predominant component (carbonate, siliceous), structure, and probable genesis. Within each group, a specific set of void space types were allocated. Only minor part of pores was associated with a mineral matrix; it was shown that the majority of void space is concentrated in the organic-mineral association (a polymer compound of organic matter and mineral component). Images obtained from scanning electron microscope show that the pore size in rock samples varies from 1 to 10 μm. And there is a strong connection between amount of organic matter and porosity coefficient. [ABSTRACT FROM AUTHOR]

The upper Triassic and lower Cretaceous sediments within the Euphrates graben are one of the most important oil and gas reservoirs to the east of Syria. Based on sedimentological investigations of core materials using methods of optical and scanning electron microscopes (SEM), accompanied with EDS and XRD analyses, four major lithofacies have been detected in the upper Triassic sediments, these include; 1) Lithofacies major sandstone bodies (code: Sst-1); up to 60 m in thickness, composed of medium to coarse-grained sandstones with clay material content up to 10%, they are interpreted as deposits of a meandering rivers. 2) Lithofacies minor sandstone bodies (code: Sst-2); thickness up to 4 m, consists of very fine to coarse-grained sandstones, with clay content up to 25%, they are interpreted as minor fluvial channels and crevasse supply deposits. 3) Lithofacies claystone (code: Cls-1); include several types of sublithofacies, and interpreted as floodplains deposits, 4) Lithofacies dolomite and dolomitic claystone (code: DClst-1); interpreted as lagoonal deposits formed in brackish water environments. Two major lithofacies have been detected in the lower Cretaceous sediments, these include; 1) Lithofacies claystone (code: Cls-2); form intervals of 1 to 10 m thickness, and has medium to moderate dark gray colors. The origin of the claystones are thought to be as deposition in moderately saturated environments with oxygen, marine or estuarial conditions of a low marsh. 2) Lithofacies sandstone bodies (code: Sst-3); among this lithofacies, several sublithofacies are detected. The sediments of this lithofacies and their sublithofacies are interpreted as sediments formed under the conditions of delta to coastal marine sediments. [ABSTRACT FROM AUTHOR]

Au mineralizations of Jales and Gralheira, located in Trás-os-Montes, near Vila Pouca de Aguiar (northern Portugal), belong to the Jales Mining District, the main historic producer of gold in Portugal. Mineralizations are hosted by syn- to late-tectonic Variscan granites and by Palaeozoic metasediments ranging in age from Ediacaran to Devonian. The studies carried out consisted of the analysis of samples from drill cores (provided by the Consortium AM- Almada Mining, S.A. and EDM, Empresa de Desenvolvimento Mineiro, S.A.) and rock samples collected in the field. Characterization and macroscopic description of the samples, petrographic and metallographic study, complemented with the Scanning Electron Microscope (SEM) and Cathodoluminescence (CL) were carried out. These techniques allowed identifying for the first time, in these mineral assemblages, species such as pentlandite, xenotime-Y, monazite-Ce. This research also contributed to the better knowledge of these mineralizations, namely with respect to their mineral paragenesis, allowing to update the paragenetic table for the Gralheira deposit. Four main stages of mineralization and a remobilization stage were distinguished. The studies allowed not only to integrate the mentioned new observed minerals on the Jales/Gralheira paragenesis but also into changes on the relationship and order of deposition of some minerals. [ABSTRACT FROM AUTHOR]

Mineral processing products must be verified in order to develop highly effective technology of enrichment. At every stage of mineral processing - improvement is possible through monitoring and verification of the components of processes. Process control is possible, among others, through comprehensive mineralogical analyzes of ores and products of their processing. Automated mineralogy based on scanning electron microscopy technique, like QEMSCAN® or MLA, gives opportunity to obtain complex data in a relatively small period of time. In these studies results of Polish copper ores investigation based on samples from 3 mining areas and 3 different ore enrichment plants are presented and discussed. Polish deposits are polymetallic, with copper present mainly in chalcocite, bornite, chalcopyrite and covellite. Other important metals such as lead and zinc are present in the deposit as galena and sphalerite. Presented studies are based on QEMSCAN® measurements of concentrates and tailings that give complex data about these processing products. Data obtained from each sample contain such important factors as mineral composition, particle size distribution, liberation of sulphides and mineral associations. These factors can be good indicators of upgrading processes efficiency and can define the reasons for reducing the quality of concentrates. Moreover mineral composition of tailings can indicate the causes of metal loss in the final product. [ABSTRACT FROM AUTHOR]

Due to the global problem of desertification, the demand in the diagnostics of the soil forming in the desert conditions is increased. The desert varnish and the vesicular (porous) crust horizon are distinctive morphological features of desert landscapes and, at the same time, generally recognized features of desert soil formation, being commonly referred to as the yermic horizons in different sub-groups within reference groups of desert soils. The objects of the present study were the surface horizons of vesicular crust and desert pavement in extremely arid soils of the Mojave (USA) and Trans-Altai Gobi (Mongolia) Deserts. The study methods included tomographic c analyses (using a Bruker SkyScan 1172 microtomograph), micromorphological analyses (using an Olympus BX51 polarizing microscope equipped with an Olympus DP26 digital camera) and submicromorphological analyses (using a JEOL JSM-6610LV scanning electron microscope with an INCA Energy X-Ray analyser) with determination of the elemental composition of pedofeatures and minerals in different parts of desert varnish cross-sections. Our research on the surface horizons of extremely arid soils developed within the ancient piedmont plains has revealed a large complex of similar elements of microfabrics. The microchemical composition of the darkest and thickest varnish from deserts of different continents is similar and does not depend on the bedrock composition. Thin varnish films have deferent composition depending on the microrelief of rock fragment surface. Combining the data of micromorphological and microchemical analyses of numerous samples has allowed us to suggest that desert varnish development is a polygenetic and polychronic process. We believe that the formation of desert varnish as well as light-coloured vesicular porous surface crust horizons of desert soils can be interconnected and predetermined by hydrophysicalbiochemical processes with a leading role of water movements within moisture films and an explosive character of microbiological activity. [ABSTRACT FROM AUTHOR]

Holocene alluvial and lacustrine deposits characterize the so-called Quatrnary fills of the Bor Basin (central Turkey) and consist of conglomerate, sandstone, mudstone, limestone, and paleosol-calcrete units. To understand the any climate changes hidden in sedimentary rocks and paleosols and pedogenic processes mentioned above, it is planned to perform XRD (X ray diffraction), SEM (Scanning Electron Microscope), XRF (X-Ray Fluorescence) and stable isotope element analysis due to determine for the analysis of geochemical, mineralogical sedimentogical compositions. During the Late Glacial, a shallow freshwater lacustrine phases and paleosols are identified from 40 000 to 11 000 yr BP. The Holocene environmental evolution shows a period of paleosols, marsh or shallow lake sedimentation from 6 000 to 5 500 yr BP. This period is interrupted by second drought period and this corresponds to calcareous rich mudstones in the area. This is covered during the Late Holocene by the renewal of marshes, shallow lake sediments and paleosols. The temperature increase during the last period, uprising and closed basin structure, salinization started taking place and the process still continues due to palaeoclimatical changes. [ABSTRACT FROM AUTHOR]

This article is a result of investigation oolitic iron ores from Bakchar deposit by: X-ray crystallography, simultaneous thermal analysis (STA), and a scanning electron microscope (SEM) combined with an energy-dispersive micro analyzer. The Bakchar iron ore deposit is located within the West Siberian iron ore basin, which is a large strip of the Cretaceous-Paleogenic littoral sediments with oolitic iron ores overlapped by a thick series (160-200 m) of the Neogene-Quaternary age [1]. The mineral composition of ores was studied in 1950-70s and described in many papers [2]. In 2005, mineral exploration and evaluation started again in the Bakchar deposit. As a result, large-scale works on defining geological composition of the deposit, and studying material composition of the oolitic iron ores were started. The oolitic iron ores were studied from one ore cut (Eastern part). The mineral composition includes many different minerals: terrigenous (quartz, feldspars, magnetite, ilmenite, zircon, rutile and many other), authigenic and clay (carbonates, glauconite, chlorite, goethite, hydrogoethite, lepidocrocite, phosphates, sulfides, and native silver) [3]. The most interesting minerals for studying genetics are clay minerals. This study was funded by the Russian Ministry of Education and Science, program "State consigning" and has been performed in the "Analytical center of geochemistry of natural systems" at National Research Tomsk State University. [ABSTRACT FROM AUTHOR]

Small samples of native gold from Rosia Montana (Apuseni Mts.) and from Cavnic (Baia-Mare district) were scanned by micro-PIXE method to identify especially minor (between 0.1 and 1%) elements and possible micro-inclusions (micro-areas of different composition from the surrounding material - e.g. rich in tellurium and antimony). The samples were also studied using an AXIO IMAGER - Carl Zeiss polarized light microscope and a Scanning Electron Microscope (SEM) from FEI, model Inspect S with an Energy Dispersive X-Ray Spectroscopy (EDAX) unit. Analyzed samples are from recovery obtained by inhabitants from landfills of former mining plants. For Rosia Montana we detected micrometer areas (5 µm X 5 µm) rich in Ag and Sb and without Au, Sb/Ag ratio being 1/3.5-4.5, polarized light microscopy and SEM-EDAX analysis confirming the presence of pyrargyrite-proustite. For Cavnic-Roata samples, one micro-area revealed at micro-PIXE an important presence of Te (16657 ppm), a significant presence of Sb (2861 ppm) and an increase of Ag content, indicating the presence of a Ag telluride. Polarized light microscopy and SEM-EDAX analysis confirmed the presence of cervelleite and argentite (acanthite). [ABSTRACT FROM AUTHOR]