Search

Abstract: Microclimates of large cities and global warming favor the range expansion of the Far-Eastern invasive fish Perccottus gleniiin northern regions of Europe where this invader becomes a component of local ecosystems and participates in transmission of parasites and pollutants along food chains. We have assessed contents of seven trace elements in muscle tissues of this invasive fish in 16 water bodies within the city of Moscow. In all water bodies studied, quantities of all studied elements did not exceed the maximum concentrations permitted in national and international guidelines. Therefore, the screened water bodies of Moscow may be assessed as unpolluted. The fish P. gleniiis a convenient object for assessing pollution levels of city ponds, since this fish species is now widespread, reaches a high population densities in shallow aquatic sites, may be caught easily, no permit is required for its capture because the species is recognized as invasive, and its partial elimination does not damage native freshwater ecosystems.

Abstract: The crystal structure of a mineral of the cancrinite group with an aluminosilicate framework of the marinellite type and a dominant sulfite group \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\text{SO}}_{3}^{{2 - }}$$\end{document}in one of the extraframework sites in the liottite cavity is studied. The studied mineral is derived from a paleovolcano near Magliano (Lazio, Italy) and is one of the major rock-forming phases of the leucite–nepheline syenite. The divergence factor was R= 5.71% for 6819 independent reflections with I> 2σ(I). The studied mineral is trigonal, space group is P31c, and the unit cell parameters are a= 12.87267(18), c= 31.7393(5) Å, V= 4554.75(15) Å3. The crystal chemical formula Na29.78K11.82Ca6.40(Si36Al36O144)(SO4)6(SO3)2Cl2(OH)0.40⋅3.98H2O (Z= 1), which is based on the results of XRD structure analysis, is consistent with electron-microprobe data. The presence of the \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\text{SO}}_{3}^{{2 - }}$$\end{document}anion was confirmed by the Raman spectrum.

Abstract: The oxidation state of Mn is determined for the first time by iodine titrimetry, and the Mn4+/Mn3+ratio (54/46%) is identified for Mn-sturmanite from the N’Chwaning 2 Mine (Kalahari manganese field, South Africa). The Mössbauer spectrum of sturmanite, which contains a single asymmetric Lorentz doublet with parameters RTISα-Fe= 0.31(1) mm/s, RTQS = 0.18(1) mm/s, FWHML= 0.55 mm/s, and FWHMR= 0.33 mm/s, confirms the presence of Fe3+only in the composition of the mineral. The process of its thermal transformation is studied using thermal analysis and IR spectroscopy: dehydration and decomposition of Ca polyhedra, dehydroxylation, decarbonatization, and complete decomposition of structure with the formation of anhydrite, hematite, and Ca borates occur up to 200, 600, 750, and 1000°C, respectively. The chemical formula of the studied sturmanite, which is calculated on the basis of our studies per eight cations, is as follows: Ca5.94\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\text{Fe}}_{{1.03}}^{{3 + }}{\text{Mn}}_{{0.54}}^{{4 + }}{\text{Mn}}_{{0.44}}^{{3 + }}$$\end{document}Al0.03Si0.02[B(OH)4]1.00[B(OH)3]0.11[SO4]2.32[СО3]0.49(OH)12⋅22.7H2O. The unit cell parameters of the mineral are determined using X-ray powder diffraction: a= 11.148(3) Å, c= 21.830(9) Å, and V= 2349(2) Å3. The unit cell parameters of minerals of the sturmanite–jouravskite series linearly decrease with an increasing mole amount of the jouravskite endmember. It is suggested that the studied mineral can be an intermediate member of the sturmanite–jouravskite series with heterovalent isomorphic substitution according to following schemes: Mn3+and Mn4+→ Fe3+in the cation octahedral site and [CO3]2–→ [B(OH)4]–and [SO4]2–in the anion site.

Abstract—: The article describes the main socio-economic consequences of short-term interregional labor migration and presents some estimates for Russia. A new tool for forecasting intracountry flows of migrant workers, which differs from those previously used in the scientific literature is proposed. The model, taking into account a number of factors, through the estimation parameters over the retrospective period selects the distribution function of the total labor flow by region, based on which scenario calculations of future incoming migration flows are implemented depending on the regional dynamics associated with the development of the macroeconomic situation. Based on the forecast vectors, matrices (checkerboards) of labor migration for each forecast year have been reconstructed. It is concluded that even low rates of economic development will be a factor affecting the growth in the number of internal labor migrants. Despite the fact that several scenarios have been considered, given the higher growth rates for the regions of Asian Russia, the spatial structure of labor migration remains stable relative to the reporting period, which also “preserves” the socio-economic consequences of labor migration for the regions.

Abstract: Unusual chemical and structural varieties of two lovozerite-group minerals from the Lovozero alkaline complex (Kola Peninsula) were studied by means of electron microprobe analysis, single-crystal X‑ray diffraction, and IR spectroscopy. The Zr- and Fe-rich variety of kazakovite with the composition Na6.20U0.01(H3O)0.25(Mn0.72Ca0.10)Σ0.82(Ti0.61Zr0.18)Σ0.97Si6O17.83(OH)0.17was found in the Palitra pegmatite body, Mt. Kedykverpakhk. The mineral is trigonal, R\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\overline{3}$$\end{document}m, a= 10.2622(5), с= 13.0884(7) Å, V= 1193.71(13) Å3; Rhkl= 0.0383. The variety of trigonal litvinskite from Mt. Alluaiv is characterized by the lowest total content of large cations sum (Na, Ca, and Mn) and the space group previously unknown for this mineral R3m. Its composition is Na2.05(H2O)0.64(Mn0.13Ca0.02)Σ0.15(Zr0.93Ti0.06\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\text{Fe}}_{{0.02}}^{{3 + }}$$\end{document}])Σ1.01Si6O12.36(OH)5.64, and unit cell parameters are: a= 10.1880(10), с= 13.1209(16) Å, V= 1179.4(3) Å3; Rhkl= 0.0665. The presence of hydronium H3O+was first revealed for lovozerite-group minerals. The possibility of formation of kapustinite and litvinskite as a result of the step-by-step townendite alteration process (decationization with the replacing of the corresponding part of O2–by OH–) is discussed.

Abstract: Natisite, a natural tetragonal (P4/nmm) modification of Na2TiSiO5= Na2TiO(SiO4) is an abundant indicator mineral of relatively low-temperature (no higher than 300–350°C) peralkaline (hyperagpaitic) hydrothermal assemblages in the Lovozero and Khibiny alkaline plutons, Kola Peninsula, Russia. The proportion of natisite in hypersodic (with Na \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \gg $$\end{document}K) hydrothermal veins in Lovozero and in the hydrothermally altered zones of potassium-rich pegmatites in Khibiny is up to 30 and 10 vol %, respectively; i.e., natisite can be a rock-forming mineral and the major Ti concentrator in the rock. In Lovozero, natisite is a primary mineral crystallized from hydrothermal solution, whereas in Khibiny, natisite is secondary: it predominantly occurs as pseudomorphs after earlier Ti minerals, namely, ilmenite, titanite, aenigmatite, lamprophyllite and rinkite. The chemical composition of natisite is rather stable, close to Na2TiSiO5. A very bright blue to bluish white fluorescence in shortwave ultraviolet light (λ = 245 nm) is an important identification feature of natisite. The crystal structure of natisite was first solved for a natural sample (Mt. Rasvumchorr, Khibiny), R1 = 1.97%. A comparative study of natisite and other titanosilicates with tetragonal pyramids TiO5revealed a distinct negative correlation between the length of an essentially covalent Ti–O bond in the titanyl group and the frequency of its stretching vibrations in the IR spectrum.

Abstract: Dalnegorskite, a new pyroxenoid with the crystal chemical formula Ca2Ca2MnCa(Si3O9)2and simplified formula Ca5Mn(Si3O9)2, is a rock-forming mineral in the B-bearing calcic skarns in the Dalnegorsk borosilicate deposit (Dalnegorsk, Primorsky Krai, Russia). It belongs to the bustamite structural type and forms a continuous solid-solution series with isostructural ferrobustamite Ca2Ca2FeCa[Si3O9]2. These pyroxenoids form beige, pinkish white and milky white radiated aggregates typically consisting of split thin acicular to fiber-like individuals and are associated with hedenbergite, datolite, andradite, galena, sphalerite, and pyrrhotite. Dmeas.= 3.02(2), Dcalc.= 3.035 g cm–3. Dalnegorskite is biaxial negative, α = 1.640 (3), β = 1.647 (3), γ = 1.650 (3)°, 2Vmeas.= 75(10)°. The average chemical composition of the holotype (electron microprobe data) is: 0.23 MgO, 40.02 CaO, 5.02 MnO, 3.64 FeO, 50.65 SiO2, total 99.56 wt %. The empirical formula calculated for 18 O atoms is Ca5.03Mn0.51Fe0.36Mg0.04Si6.01O18. The crystal structure of the new mineral was obtained from X-ray diffraction data using the Rietveld method, Rp=0.0345, Rwp=0.0444, R1= 0.0790, and wR2= 0.0802. Dalnegorskite is triclinic, P-1, a= 7.2588(11), b= 7.8574(15), c= 7.8765(6) Å, α = 88.550(15), β = 62.582(15), γ = 76.621(6)°, V= 386.23(11) Å3, and Z= 1. Dalnegorskite is distinct from the related mineral wollastonite in the infrared spectrum. The wave numbers of the maxima of strong bands in the Si–O stretching vibration region in the IR spectrum of dalnegorskite are (cm–1): 905, 937, 1025, and 1070. The holotypic specimen of dalnegorskite is kept in the collection of the Fersman Mineralogical Museum, Russian Academy of Sciences, Moscow, Russia (no. 96201).

Abstract: Thermal behavior of catapleiite, ideally Na2ZrSi3O9⋅ 2H2O, has been investigated with the X-ray diffraction, electroconductivity measurements using impedance spectroscopy, dynamic scanning calorimetry, thermal gravimetry, and infrared spectroscopy. The high-temperature transformation product of catapleiite obtained after annealing of catapleiite at 1000°C has been studied. This is a new microporous zirconosilicate, ideally Na6Zr3[Si9O27], representing a new structural type. It is hexagonal, P63/mcm, a =11.5901(9), c= 9.9546(9) Å, V =1158.05(16) Å3. Its crystal structure model has been obtained using single-crystal X-ray diffraction data and refined by the Rietveld method on the basis of the powder X-ray diffraction data (R =3.87%). The structure is based on the heteropolyhedral framework, which substantially differs from that of catapleiite and is built by nine-member rings Si9O27formed by SiO4tetrahedra linked with isolated ZrO6octahedra. Extraframework Na cations are located in broad channels of the framework and between the tetrahedral Si9O27rings.

A number of rare phosphates have been found in specimens from the Chalotskoe pegmatite deposit, Transbaikal region, Russia: väyrynenite, MnBe[PO4](OH,F); parascholzite, CaZn2[PO4]2· 2H2O; messelite, Ca2(Fe2+,Mn)[PO4]2· 2H2O; eosphorite, MnAl[PO4](OH)2· H2O; moraesite, Be2[PO4](OH)4H2O; and fluorapatite. Väyrynenite forms pink grains 2–3 mm in size, less frequent prismatic crystals up to 0.8 × 3.0 cm, and spheres up to 3 mm in diameter. Parascholzite occurs as pockets up to 0.6 × 1.0 cm composed from snow-white small grains. Messelite forms pale yellow honeycomb grains and poorly shaped crystals up to 1 mm. Eosphorite has been seen in the Chalotskoe pegmatites before, but it has not been studied in detail. It occurs as red-brown prismatic crystals up to 8 cm in length, occasionally forming openbook- like aggregates and pink to pale pink grains up to 5 mm in size. Moraesite forms snow-white fibrous aggregates up to 5 × 6 mm, together with white spheres and short prismatic crystals of fluorapatite up to 1 mm. Microcline, albite, quartz, muscovite, beryl, schorl, almandine-spessartine, columbite-(Fe), and bertrandite are associated minerals. Väyrynenite and parascholzite are found for the first time in Russia.

The crystal structure of lemanskiite is determined for the first time (R= 0.019) and the mineral is redefined. Its chemical formula, crystal system, space group and unit-cell parameters are revised. The powder X-ray diffraction pattern of lemanskiite has been correctly indexed; the IR spectrum of an impurity-free sample has been obtained. It has been shown that the mineral is not a dimorph of lavendulan NaCaCu5(AsO4)4Cl · 5H2O and differs from the latter by a lower H2O content. The studied sample was from the oxidation zone of the Perseverancia deposit, Guanako, Antofagasta, Chile. It empirical formula is Na0.98(Ca0.98Sr0.03)Σ1.01Cu5.07As3.97O15.97Cl1.03· 3H2O; the idealized formula is NaCaCu5(AsO4)4Cl · 3H2O. The mineral is monoclinic, P21/m, a= 9.250(2), b= 10.0058(10), с= 10.0412(17) Å, β = 97.37(3)°, V= 921.7(3) Å3, Z=2. Lemanskiite represents a new structure type in the lavendulan group. Its structure is based on heteropolyhedral layers composed of clusters consisting of four edge-shared distorted Cu-centered tetragonal pyramids joined with eight AsO4tetrahedra, which are also linked with a Cu-centered plane squares not involved in the clusters. Interlayer edge-shared Na-centered trigonal prisms and Ca sevenfold polyhedra are linked with the heteropolyhedral layers from both sides.

Unusual, high-grade iodide mineralization comprising marshite, miersite, and iodargyrite has been discovered in the oxidation zone of the Rubtsovskoe VHMS base-metal deposit, Northwest Altai, Russia. The distribution of iodides reveals distinct zoning. Iodargyrite is widespread in the upper part of the oxidized orebody at the hypsometric level of +156 to 163 masl. The iodargyrite zone extends for more than 150 m. The content of iodargyrite in gossan occasionally reaches 1–5 vol %. Marshite is localized at the lower level (+146 to +151 masl); the zone enriched in marshite is about 50 m in extent. The marshite content in the high-grade oxidized ore with native copper and in the zone of wall-rock argillic alteration is typically close to 1 vol %, occasionally reaching 7–10 vol %. Miersite occurs sporadically in association with both iodargyrite and low-Ag marshite, which are antagonistic mineral species. Iodargyrite is stoichiometric AgI (2Hpolytype with a= 4.574 and c= 7.519 Å). Isostructural cubic marshite CuI and miersite (Ag,Cu)I make up an isomorphic series within compositional limits Mar100Mie0-Mar9Mie91and a break between Mar82.5Mie17.5and Mar57-Mie43; the aparameter of their unit cells varies from 6.050 to 6.424 Å. The crystal morphology, properties, and mode of iodide occurrence are described in the paper. According to the suggested genetic model, the source of iodine was related to exhalations of seafloor fumaroles accompanying volcanic-hydrothermal-sedimentary ore formation. Iodine is absorbed by clay in the wide zone of wall-rock argillic alteration. During the early stages of sulfide ore oxidation, sulfuric acid oxidized iodine to (I5+O3)−, and it was subsequently reduced and fixed in poorly soluble Ag+and Cu+iodides.