The structure, composition, and specificity of accumulation of trace elements by rounded nodules in gleyic soddy brown-podzolic soils (Gleyic Luvisol (Manganiferric)) of nature reserves and a national park in the south of the Far East have been studied by advanced analytical methods and noninvasive techniques. The nodules are characterized by pronounced differentiation into external (brown and ocher-brown, Fe-enriched, and dense) and internal (dark brown, Mn-enriched, and loose) zones. According to the distribution of Mn compounds in the internal zone, two types of nodules are identified: with an undifferentiated internal zone and with a core (cores). The cores contain C-enriched microzones, which are centers of Fe and Mn precipitation. The stages of coprecipitation of Fe and Mn and the stages with predominant precipitation of one of the elements are identified in the nodules. The nodules consist of a complex of minerals inherited from soils, as well as of nodule-specific minerals (goethite, feroxyhyte, and birnessite). The Fe content in the nodules is, on average, four times higher than that in the soil, the Mn content is 21.9 times higher, and the C content is 3.6 times higher. The most intensive accumulation in nodules is typical for Pb (EF = 5.53–12.14), which is determined by the joint participation of C- and Mn-containing compounds in its binding. Nickel (EF 0.89–5.81) and Cr (EF 1.22–2.60) are less actively accumulated; and the accumulation of V (EF 0.85–1.88) and Sr (EF 0.58–1.43) is weak. The phases accumulating Ni, Cr, V, and Sr are represented by nodules containing Fe and C. Zinc does not accumulate in the nodules. A comparison of the concentrations of water-soluble forms of trace elements reflects a decrease in the mobility of Cr, Pb, Ni, V, and Sr in nodules as compared to soils.

Ore crusts with a germanium content of up to 96 ppm were discovered in the Sea of Japan. This is tens of times higher than the clarke of the Earth’s crust. Germanium-rich crusts were dredged together with intermediate and felsic volcanic rocks. The crusts are composed predominantly of iron oxyhydroxides (goethite) and contain germanium in the dispersed state.

This article presents new data on the abundance and ways of dissolved trace elements (Si, Fe, F, Al, Sr, Br, B, Mn, Ba, Ti, Li, Rb, Mo, As, U, Th, W, Sc, Y, REE, and Hf) in thermomineral, surface, and ground waters of the northern Tien Shan (Issyk-Kul intermountain depression). It has been established that the trace element composition of thermomineral waters can serve as a marker of hydrogeological settings of water formation and flow: waters of sedimentary rocks of the intermountain artesian basin are enriched with Sr, Ba, Mn, B, Mo, and U, while the waters of rock massifs contain increased concentrations of F, Rb, W, and Sc. Thermodynamic calculations performed for certain trace elements in Visual-MINTEQ 3.1 and GWB 14 have made it possible to identify the water migration patterns of the surveyed water points. Calculation of the water migration coefficient has shown the dependence of the rate of microcomponent accumulation on the type of water-bearing strata and hydrogeological conditions of water formation.

Abstract Particles in welding fumes (WFs) generated through arc welding operations pose serious health concerns to the welders through their exposure to heavy metals. In this study, the influence of different covering types of industrial electrodes (rutile, basic, acid, rutile-cellulose) on the particle size distribution, morphology, and elemental composition of particles of welding fumes was investigated. Quantitative analysis was conducted in order to determine the distribution of particles with diameters of 10μm, or less, (PM10 fraction) of the WFs within the workplace, followed by the comparison of the results with the current international normative documents on the maximum permissible concentration of the PM10 fraction in the working zone air. The most hazardous types of electrode coverings were determined based on the dispersion, chemical composition, and concentration of formed particles of the PM10 fraction in space and time. The dependence of the particle size distribution time of the WFs in the working zone was identified for a basic covered industrial electrode. The maximum sizes of WF particles were reported for operations held at 100 A with electrodes having the rutile-cellulose type of covering, and at 150 A having the basic type of covering. A concentration of 0.05 mg/m3 for the PM10 fraction of WFs in the workplace was achieved after 1 hour of the welding machine operation at a current equal to 100 A. Thus, the results of the characterization of WFs demonstrate the risks of the arc welding process to human health and stress the need for their control and mitigation. According to the results of the study, a proportional relationship between the average particle diameter and the WF particle distribution period in the workplace has been demonstrated, which has been particularly evident from the height of the WF particles. 3D modeling of the dispersion of WF particles during welding arc operations proved to be a suitable method for their characterization.

The first case of hydrothermal brecciated crusts composed of goethite with quartz veinlets is described for the Sea of Japan.

The article substantiates the possibility of obtaining composite materials with improved functional properties to strengthen the subgrade, containing technogenic soil stabilized by an additive based on a gelling polymer. The introduction of technogenic soils into composites will not only reduce the consumption of expensive materials, but also solve a complex of acute environmental problems. Composite materials can be used in the construction of structural layers of road pavements, foundations of buildings and structures, sites for various purposes, for the prevention and elimination of defects in the foundations of engineering structures during their construction, reconstruction and repair, including in permafrost areas. Stabilized technogenic soils are more durable, frost-resistant and waterproof, which makes them applicable for creating impervious curtains in hydraulic structures and sealing storage facilities for hazardous substances. The cryogenic effect on a composite material allows one to vary its properties within a wide range and modify its macroporous structure. Studying the process of structure formation of the resulting organic-inorganic materials, consisting of macromolecules of high-molecular substances and inorganic inclusions that have undergone cryogenic treatment, will make it possible to specifically regulate their performance characteristics. The best values of strength characteristics were obtained for samples with a stabilizing additive concentration of 100 g/l. The resulting composite materials are hydrophobic, frost-resistant, characterized by a compressive strength of 2.3-6.5 MPa and a thermal conductivity of 0.19-0.20 W/(m & sdot;K). Data from differential scanning calorimetry and thermogravimetry and IR spectroscopy revealed that the binding of mineral particles by a stabilizing additive occurs due to the formation of organomineral complexes with the participation of clay minerals and the restructuring of hydration shells. SEM data indicate that crystallinity zones formed due to hydrogen bonds of hydroxyl groups of neighboring polymer chains can participate in the formation of the composite structure. An increase in the number of cryogenic treatment cycles promotes additional structuring and strengthening of the polymer phase due to the formation of additional nodes of the supramolecular network, ordering of crystallinity zones and the appearance of compacted areas in the structure. Computed X-ray tomography revealed an increase in the density of the composite upon drying, which helps to increase its strength characteristics. The structure of the sample is characterized by heterogeneity of the pore space, which is characterized by the presence of both fine -porous and large -porous regions, which determines its thermophysical properties.

The article presents and analyzes the results of microscopic and microprobe studies of polished sections of the Konder deposit. We have identified ore minerals of the sulfosalt group, and provide data on their chemical composition, spatio-temporal relationships. The joint finding of sulfosalts of lead, silver, antimony, tin, nickel and copper, representing geochemically contrasting groups, allows us to continue the discussion of the history of the formation of the deposit and to clarify some of the features and originality of the named parageneses.

Gemological, spectrometric, and chemical properties of alluvial diamonds and their micro inclusions from the Nezametninskaya area, which consider to be diamond-bearing by means of many researchers, were examined. We investigated the sorting of studied diamonds according to their particle size distribution, a complex of the most characteristic typomorphic features, the way the inclusions are located and their contents, ultraviolet microscopy, detection of metal particles on the surface of grains (nickel, cobalt, copper) which are used to provide a greater bond in the manufacture of industrial diamonds. This scientific research has shown us the found minerals have a synthetic origin.

Manganese crusts, composed of manganite with an admixture of pyrochroite and quartz, are revealed for the first time in the Sea of Japan. According to a combination of features, these are low-temperature hydrothermal mineral formations that appeared on the slope of the South Yamato Ridge at a depth of no more than 1300 m under conditions of oxygen deficiency.

This study delves into the novel utilization of Aristolochia manshuriensis cultured cells for extracellular silver nanoparticles (AgNPs) synthesis without the need for additional substances. The presence of elemental silver has been verified using energy-dispersive X-ray spectroscopy, while distinct surface plasmon resonance peaks were revealed by UV-Vis spectra. Transmission and scanning electron microscopy indicated that the AgNPs, ranging in size from 10 to 40 nm, exhibited a spherical morphology. Fourier-transform infrared analysis validated the abilty of A. manshuriensis extract components to serve as both reducing and capping agents for metal ions. In the context of cytotoxicity on embryonic fibroblast (NIH 3T3) and mouse neuroblastoma (N2A) cells, AgNPs demonstrated varying effects. Specifically, nanoparticles derived from callus cultures exhibited an IC50 of 2.8 µg/mL, effectively inhibiting N2A growth, whereas AgNPs sourced from hairy roots only achieved this only at concentrations of 50 µg/mL and above. Notably, all studied AgNPs’ treatment-induced cytotoxicity in fibroblast cells, yielding IC50 values ranging from 7.2 to 36.3 µg/mL. Furthermore, the findings unveiled the efficacy of the synthesized AgNPs against pathogenic microorganisms impacting both plants and animals, including Agrobacterium rhizogenes, A. tumefaciens, Bacillus subtilis, and Escherichia coli. These findings underscore the effectiveness of biotechnological methodologies in offering advanced and enhanced green nanotechnology alternatives for generating nanoparticles with applications in combating cancer and infectious disorders.

Data on the thermodynamic analysis of the chemical affinity values of the oxides of the elements that constitute titanium-containing concentrates with respect to fluorinating reagents (HF, NH4F, NH4HF2) and on the thermochemical reaction processes of silicon dioxide, various dispersions, and ammonium hexafluorotitanate upon steam heating are provided. The predominant formation of ammonium hexafluorosilicate, which binds the products of pyrohydrolysis of titanium salts upon formation, sublimates at a temperature of 250–300°C, is captured outside the pyrohydrolysis zone, and reduces the temperature of pyrohydrolysis, is confirmed and recommended for application in the hydrofluoride technology used in the production of titanium dioxide. Data on the morphology of titanium dioxide powders are obtained.

Garnet megacryst with a multiphase inclusion from intraplate alkali basalts of the Shavaryn Tsaram (Tariat, Mongolia) was the object of the study. This unusual aggregate consists of porous glass, Ti‐rich biotite, orthopyroxene, spinel, clinopyroxene, olivine, and ilmenite. WinTWQ 2.32 thermodynamic simulation of this system revealed a few intervals of equilibrium. Pressure and temperature adjustment reflected in the paragenetic minerals of the melt pocket. The capture of already crystallised garnet megacryst was at P = 0.8–1 GPa and T = 1120–1160°C. Mineral crystallisation inside the melt pocket, accompanied by external inputs, occurred at P = 0.75–0.95 GPa; T = 790–1120°C. Symplectite assemblage formed in the garnet megacryst due to decomposition at ( P = 0.55–0.7 GPa; T = 850–930°C). The study of the oxygen isotope content in primary garnet and biotite of the melt pocket showed that the δ 18 O VS M OW values are the same and correspond to that of typical mantle xenoliths. However, the chemical and microcomponent composition of the melt pocket minerals reveals a material that differs from basalts and peridotites. Thus, it has been revealed that the multiphase inclusion in the garnet megacryst formed not only on account of the garnet's substance, but also due to the entrapped material of the Earth's interior.

We have carefully studied an unusual sulfide-bearing garnet megacryst from the ever-surprising Cenozoic Shavaryn-Tsaram basaltic cone (Tariat Platou, Mongolia). Similar sulfide inclusions in minerals constituting mantle xenoliths and clinopyroxene megacrysts related to alkali basalts were already known (Peterson and Francis, 1977, Chaussidon et al, 1989, Ionov et al, 1992) but they have never been found in garnet megacrysts. Since these garnets are believed to be mantle-derived material, their sulfide inclusions provide information on the deep sulfur cycle. The sulfide-rich garnet megacryst from Shavaryn Tsaram pyroclastic strata is a chip of a large (up to 3 cm) cracked and partly quenched glassy crystal (fig. 1A, fig.1B) with melt pockets (Aseeva et al, 2021) inside (fig. 1C). Sulfide inclusions are primary, isometric, elongated, and orientated towards crystal growth with a distinctive arrangement (3D X-ray images, Skyscane, fig. 2A). Swarms of inclusions contour the growth planes typical for the deltoidal icositetrahedron (fig. 2B). Sulfide inclusions mainly consist of Ni-bearing pyrrhotite (1.66-2), scarce chalcopyrite (fig.3A and B), and rarely of pentlandite. Incompletely crystallized droplets of MSS (monosulfide solid solution) occur periodically as thin crystal pyrrhotite and pentlandite intergrowths (fig. 3C). These MSS inclusions are thought to be a product of the sulfide melt exsolution caused by undercooling (Chaudison et all, 1989). The multi-isotope sulfur composition of these sulfide inclusions has been studied to define whether the sulfur source is crustal or mantle-derived. Thus, their δ34S values account for 0.2-0.4‰, δ33S for 0.1-0.2‰, and Δ33S for 0.00-0.03‰, which is characteristic of mantle, meteoric, MORB, and volcanic settings. As for the host garnet, its oxygen isotope composition (Δ18О 5.4 to 5.8‰) also suggests the volcanic origin of these sulfides. Submicron surface analysis (Bruker Dimension Icon and Solver NT-MDT) reveals the linear-globular structure of garnet (fig. 4A). Being probable nuclei, nearly 1 μm globules compose layers of garnet. We assume that garnet crystal formed via epitaxial growth from the gas phase. Garnet megacryst linear structures consisting of globules differ significantly from the metamorphic garnet crystal lattice (fig. 4B). Sulfur redundancy causes sulfide droplets, immiscible with silicate material (fig. 4C), to gather and form bulbs on top of a growing crystal due to surface tension (fig. 4C). The following conclusions may be drawn: 1. Sulfide inclusions in alkali basalt-associated garnet megacrysts are primary. 2. Sulfides hosted in garnet are mantle-derived according to isotopic data. 3. Garnet megacryst formation was caused by epitaxial growth.

Ferruginous (goethite) mixed-type hydrothermal–hydrogenetic crusts, which were found in the Sea of Japan for the first time, are described. Compared to manganese (todorokite, birnessite) mixed-type hydrothermal–hydrogenetic crusts, which are common in the Sea of Japan, ferruginous crusts were probably formed under higher temperatures and closer to the hydrothermal fluid outlets on the seafloor. The substance that hydrogenetically precipitated to the crusts from seawater after the cessation of hydrothermal process is identified by the high contents of Th and rare earth elements and also by the positive Ce and negative Eu anomalies.

The Shared Research Facilities "Primorsky Centre for Local Elemental and Isotopic Analyses" was created based on the instrumental base of the Far Eastern Geological Institute of the Far Eastern Branch of the Russian Academy of Sciences. The Shared Research Facilities conducts its own (for the needs of FEGI FEB RAS) fundamental and applied scientific research to establish the elemental, isotopic composition and structure of both natural and artificial objects, as well as jointly with other scientific Russian and foreign institutions and universities, industrial enterprises, state and private companies that require modern, precision methods for analyzing various substances and materials, diagnosing and monitoring the condition and changes in the environment.

The distribution of rare-earth elements (REEs) in ferromanganese deposits (FMDs) from the southeastern Laptev Sea is considered. The ore part of FMDs consisting mainly of iron hydroxides (limonite) results from the process of suboxic diagenesis enhanced by bioturbation. It is responsible in FMDs for the deficiency in Ce and some enrichment in middle REEs (MREEs). The (alumino)silicate part of FMDs is genetically related with bottom sediments, corresponds to their REE composition, and most likely controls the scandium content. Because of the high formation rate of hydroxides, the total REE content in FMDs is lower than that in bottom sediments.

The present study reports a green chemistry approach for the rapid and easy biological synthesis of silver (Ag), gold (Au), and bimetallic Ag/Au nanoparticles using the callus extract of Lithospermum erythrorhizon as a reducing and capping agent. The biosynthesized nanoparticles were characterized with ultraviolet-visible (UV-Vis) spectroscopy, X-ray diffraction (XRD) analysis, and transmission electron microscopy (TEM). Our results showed the formation of crystalline metal nanostructures of both spherical and non-spherical shape. Energy dispersive X-ray (EDX) spectroscopy showed the characteristic peaks in the silver and gold regions, confirming the presence of the corresponding elements in the monometallic particles and both elements in the bimetallic particles. Fourier-transform infrared (FTIR) spectroscopy affirmed the role of polysaccharides and polyphenols of the L. erythrorhizon extract as the major reducing and capping agents for metal ions. In addition, our results showed that the polysaccharide sample and the fraction containing secondary metabolites isolated from L. erythrorhizon were both able to produce large amounts of metallic nanoparticles. The biosynthesized nanoparticles demonstrated cytotoxicity against mouse neuroblastoma and embryonic fibroblast cells, which was considerably higher for Ag nanoparticles and for bimetallic Ag/Au nanoparticles containing a higher molar ratio of silver. However, fibroblast migration was not significantly affected by any of the nanoparticles tested. The obtained results provide a new example of the safe biological production of metallic nanoparticles, but further study is required to uncover the mechanism of their toxicity so that the biomedical potency can be assessed.

The results of the hydrogeochemical study of poorly mineralized thermal groundwaters from the Kuldur Spa (Jewish Autonomous Region, Russia) are reported. These groundwaters are distinguished by their high temperature (73°С), low TDS (up to 0.38 g/L), and alkaline environment (pH 9). The dominant cation is sodium, and the dominant anion is hydrocarbonate. The waters are enriched in fluorine, silicon, aluminum, tungsten, molybdenum, and several other anionic elements. Detailed data on the chemical and mineral composition of water-hosting (intrusive) rocks are provided and the sources of the major brine components in the groundwaters are revealed. The study of the associated gases shows that the major component of the gaseous phase (N2) is atmogenic, while CH4 and CO2 are biogenic. Argon and oxygen are derived from air as well, whereas helium is predominantly of the radiogenic crustal origin. The isotope characteristics of oxygen and hydrogen in the aqueous phase indicate the undoubtedly meteoric genesis of the groundwater with an extended circulation period. The results suggest that the thermal groundwaters of the spa are formed via penetration of meteoric waters to a depth of 4 km and heating to 100 °C. The dissolved chemical elements that form the brine phase come via the dissolution of host rocks; however, since the groundwater circulates within the rocky massifs of poorly soluble granitoids, respectively, the TDS of the groundwater remains low.