Intermediate Chamber Research Articles

Osumilite-bearing lavas of the Keli highlands (Greater Caucasus): petrological and geochemical characteristics, mineral composition and conditions of magmatic melts formation

Comprehensive petrological, geochemical and mineralogical studies of osumilite-bearing andesite-dacitic lavas of the volcano Kordieritoviy (Keli Highland, Greater Caucasus), erupted at the end of the Pleistocene (about 200 Ka), were carried out. The results of petrographic study of thin sections and microprobe analysis showed that the rocks contain three paragenetic mineral associations: (1) “xenogenic” (metamorphogenic) – garnet (XPrp = 0.42, XAlm = 0.51–0.53, XGrs = 0.04–0.05) + hercynite + sapphire + bronzite + pargasite + ilmenite; (2) early magmatic – hypersthene + hercynite + garnet (XPrp = 0.21–0.31, XAlm = 0.52–0.71, XGrs = 0.04–0.13) + ferro-kersutite + ilmenite; (3) late magmatic – hypersthene-ferrohypersthene + labradorite + garnet (XPrp = 0.04–0.14, XAlm = 0.65–0.81, XGrs = 0.06–0.18) + osumilite-(Mg) + phlogopite + tridymite + ilmenite + apatite. Osumilite-(Mg) (phenocrysts, xenomorphic aggregates in the rock matrix and crystals in miarolic cavities), the average formula of which for dacites of the Kordieritoviy volcano can be written as (K0.73Na0.06Ca0.02□0.20)1.00(Mg1.06Fe2+0.90Mn0.04)2.00(Al2.75Fe2+0.18Fe3+0.06Ti0.01)3.00(Si10.34Al1.66)12O30, formed mainly at late magmatic stages – in intermediate chambers immediately before the rise of the melt to the surface or after its eruption. Accordingly, this mineral in the studied lavas has purely magmatic origin. Thermobarometric calculations and petrological modeling showed that the deep magma chamber of the Kordieritoviy volcano was located at a level of 45–53 km from the surface in near the Moho boundary. The temperature of the melt at the early magmatic stage was no less than 1100°C at 17–23 kbar. Crystallization of osumilite-(Mg) in intermediate magmatic chambers (at depths of 30–40 km) and during the process of lava outpouring occurred at 1030–870°C and pressure progressively decreasing from 14–9 to 1 kbar. A petrogenetic model has been proposed to explain the reasons for the formation of exotic osumilite-containing lavas of the Kordieritoviy volcano. Its main provisions include: (1) enriched upper mantle source (lithospheric mantle metasomatized as a result of permanent interaction at the Moho boundary with the overlying lower crust composed of metamorphosed terrigenous-volcanogenic formations); (2) generation of “dry” basaltic magmas in the source; (3) crystallization differentiation in the source (fractionation of olivine and chrome spinels) with the formation of a “dry” superheated andesitic melt; (4) limited-scale assimilation by highly differentiated andesitic melts rising to the surface of the material of the lower crust, directly below the volcano, composed of leucocratic granulites, with simultaneous fractionation of garnet, orthopyroxene and ilmenite from the melt.

Study on the influence characteristics of multi-working condition parameters on membrane electrode type CO2 electrolyzer

The electrochemical conversion of carbon dioxide (CO2) into basic chemicals or carbon-based fuels is a promising new strategy for carbon resource utilization. Within this domain, solid-electrolyte CO2 electrolyzer demonstrate significant potential for the continuous production of pure formic acid solutions. This study, leveraging a 4 cm2 visualization electrolyzer, explores the impact of three working condition parameters on performance: working voltage, gas flow rate, and the intermediate chamber water flow rate. It compares the variations in current density, formic acid concentration, and the distribution of liquid water on the cathode side under different working conditions. The results indicate that the working voltage, current density, and formic acid yield are all positively correlated; overly low gas flow rates can lead to CO2 deficiency and diminished electrolyzer performance; concentration control of the formic acid solution is effectively achieved by adjusting the intermediate chamber water flow rate; and during the electrolyzer reaction process, almost all of the liquid water is positioned at the bends downstream of the cathode flow channel.

LATE MESOZOIC RARE-METAL GRANITES, PEGMATITES, AND GREISENS OF MONGOLIA: AGE, MINERALOGY, GEOCHEMISTRY, ORE POTENTIAL, AND PETROGENESIS

Comparative analysis of the earlier obtained and new geological data, age, mineral, petrological, and geochemical compositions of plutons of calc-alkalic granitoids and rare-metal Li–F granites shows their evolution in a wide time interval during the formation of Mesozoic areas of granitoid magmatism. Mineralogical and geochemical analysis of the evolution of plutons of palingenetic calc-alkalic granitoids (Baga Hentiyn (MZ1) and Ikh Narotiin = Hiid (MZ2)) and intrusions of rare-metal Li–F granites of Central and Eastern Mongolia revealed their petrological and geochemical differences. The closure of the Mongol–Okhotsk Basin with the formation of large plutons of calc-alkaliс granitoids, obviously related to collisional processes, did not cause significant enrichment of the late granite phases with lithophile and ore elements. Within the peripheral zones of еру MZ1 and MZ2 magmatic areas, mineralization is often associated with Mongolian multiphase plutons and small intrusions of rare-metal Li–F granites. The rare-metal granites are characterized by a decrease in indicative K/Rb, Nb/Ta, and Zr/Hf values and a regular increase in F, Li, Rb, Cs, Sn, W, Be, Ta, and Nb contents during the evolution of Li–F magmas. Igneous and, particularly, metasomatic rocks in most intrusions of ore-bearing rare-metal Li–F granites are characterized by significant variations in Sn and W contents. At the magmatic stage, the pegmatoid varieties of amazonite–albite granites and pegmatites of the zonal Baga Gazriin (MZ1) and Barun Tsogto (MZ2) plutons are significantly enriched in both Sn and W. Maximum Sn and W enrichment has been established in greisenized granites and zoned greisen bodies (zwitters), which is due to the percolation of ore-bearing solutions into the upper horizons and the mineralization of ore elements in the late phases of intrusions and in metasomatites. The wide variations in the age (321–126 Ma) and trace element and isotope compositions of Mongolian rare-metal Li–F granites within various zones of large magmatic areas suggest the influence of mantle plume sources on the composition of rare-metal granitic magmas and on their ore potential in intermediate chambers in the continental crust.

MICA COMPOSITION REFLECTING CONDITIONS OF AILLIKITE FORMATION IN ZIMA COMPLEX OF EASTERN SIBERIA

Four types of mica were identified in the macrocryst and fine porphyry aillikites from the Yarma zone of the Urik-Ija graben considering specific features of morphology, chemical composition, zonation and crystallization conditions. Mica of the first type was found in macrocryst aillikites. It is available as deformed phlogopite macrocrysts rich in TiO2 (2.5–5.7 wt. %) with varying content of Cr2O3 (from detection limit to 2.0 wt. %) and Mg# 0.87–0.89 and 0.79–0.81 in different dikes. In chemical composition this phlogopite corresponds to the secondary phlogopite from mantle xenoliths, and it was obviously captured by protoaillikite melt form the rocks of the lithosphere mantle. Mica of type 2 represents phlogopite from groundmass and infrequent phenocrysts in fine porphyry aillikites and groundmass of macrocryst aillikites. In this phlogopite, TiO2 content varies in different dikes from 0.7 to 6.0 wt. %, Mg# index varies from 0.70 to 0.90. Phlogopite crystallized within the upper crust at temperature ranging from 840 to 680 °С. Mica of type 3 represents biotite (Mg# 0.40–0.65), producing rims around phlogopite and independent grains in fine porphyry and in places in macrocryst aillikites. The rims crystallized from residual Fe-rich melt at moderately heightened fO2, the temperature of biotite formation reached 700‒760 °C. Mica of type 4 is available in macrocryst aillikites as biotite (Mg# 0.40‒0.67) with phlogopite rims. It was inferred, that this biotite crystallized in intermediate magmatic chambers in the upper crust from essentially carbonate melts, separated through crystallization differentiation from protoaillikite magmas and captured by new portions of less differentiated melts. Obtained data point to metasomatic transformation of the lithosphere mantle, preceding to protoaillikite melting, under the southern margin of the Siberian craton. Thus, we may assume existence in the upper crust of the sites composed of partially crystallized melt.

The First Discovery of Archean Dolerite Dikes in the Western Part of the Aldan Shield

Dolerite dikes were studied in the western part of the Aldan terrane, in the middle reaches of the Tokko River. These dolerite dikes form a swarm of submeridional trend about 1 km wide. The dolerites of the thickest dike preserve their primary textural and structural features and mineral composition: plagioclase + pigeonite + augite + titanomagnetite. Dolerite in the chilled margins and central parts of the dike are homogeneous in composition, corresponds to low-Mg tholeiites, has low contents of Ti and other HFSE, with weak enrichment in light REE and small negative Nb anomalies. Sm–Nd isotope data on magmatic minerals of dolerite from the central part of the dike yield a good linear regression in an isochron diagram that gives to an age of 2510 ± 64 Ma, which probably corresponds to the crystallization age of the basalt. Metadolerites in a thin dike retain plagioclase porphyritic structures, but the pyroxenes are completely replaced by amphibole and chlorite. The metadolerites are contrastingly different in low contents of MgO, Cr, and Ni and in higher contents of TiO2, Fe2O3, P2O5, Nb, and all REE. The differences in the composition of the dikes may be explained by the longterm (about 65%) crystallization differentiation of the initial melt and the emplacement of the residual melt from a shallow intermediate magma chamber via opening cracks. Such conditions probably may have existed in tectonically stable intraplate settings. The age of the dolerites of the dike swarm is comparable to that of the anorogenic granites of the Nelyuki complex (~2.4–2.5 Ga), which are widespread in the western part of Aldan granulite–gneiss terrane. Our data bridge some gaps in characteristics of intraplate anorogenic magmatism that occurred in the western Aldan Shield in the Late Archean and marked the final consolidation of a large block of Archean crust in the Chara–Olekma granite–greenstone area.

Comparative mineralogy, geochemistry and petrology of the Beloziminsky Massif and its aillikite intrusions

The Beloziminsky Massif (BZM) is an alkaline ultramafic carbonatite complex that includes carbonatites, ijolites, meltegites, and syenites (abbreviated as the CIMS suite) as well as aillikite intrusions that range in age from 645–621 Ma. Aillikite intrusions also occur in the Yuzhnaya Pipe (YuP), located about 16 km eastward of the BZM. Over 5400 analyses in total were conducted to compare mineralogy and geochemistry of different rock types in this study; of these, 24 CIMS samples (>1100 analyses) and about 16 aillikites (>2300 analyses) were collected from within the BZM; the rest are aillikite mineral samples from pipes and dykes outside the massif (>2000 analyses). The results suggest significant differences in sources for rock-forming minerals, less so for the accessories. The pyroxenes in aillikite correspond either to mantle Cr-diopside xenocrysts or megacrystic augites. Low-Na Ti-augites and diopsides as well as aegirines are prevalent in the CIMS intrusive suite. Amphiboles show a considerably long compositional trend, from hornblendes to richterites. Dolomitic carbonatites include admixtures of Na, K, and Ba while calcium carbonatites often contain Sr. The carbonate-rich aillikitics are enriched either in Mg or Ca. The CIMS rocks, particularly the Ca-Mg carbonatites, often include siderites. Thermobarometry for the YuP samples, collected from outside the BZM and containing Cr-diopsides, Cr-phlogopites and Cr-spinels, suggest a formation pressure of 2–4 GPa and a temperature of 800–1250°C; augite xenocrysts with elevated HFSE, U, Th, and Al-augites trace a 90 mW/m2 geotherm.The huge thermal impact of the plume that triggered the break-up of Rodinia also created a series of ultramafic–alkaline–carbonatite massifs. Initially, the aillikites in the mantle were likely produced by the plume-induced melting of carbonated metasomatites containing ilmenite, perovskites, apatites, amphiboles and phlogopites which, in turn, were created by subduction-related melts. Any additional enrichment in the ore components might have occurred subsequentlty in the lower crust, due to liquation. The aillikites inside the BZM contain low-temperature clinopyroxenes tracing a steep advective geotherm (0.4–1.5 GPa); they also contain clots, related to intermediate depth magma chambers, together with CIMS pyroxenes and amphiboles. This suggests that the liquation of aillikites was accompanied by density separation and assimilation and fractional crystallization (AFC) fractionation with the participation of crustal material. Trace elements (especially REEs) in silicate minerals, carbonates, apatites, and accessories (perovskites, pyrochlores, monazites, columbites, zircons, ancylites, etc.) show a general rise in REE levels and La/Ybn ratios from aillikites to ijolites, and later to Fe- carbonatites. The presence of zircons, monazites, columbite-tantalites, and other Zr-Hf and Ta-Nb minerals like perovskites and tantalites in the BZM aillikites occurred due to the mixing of the silicate melts with carbonate-rich magmas at deeper levels in the crust and later, in the massif. In the aillikites, xenocrysts. Further, apatites and perovskites show high REE levels. The carbonate-silicate magmas likely passed through a system of polybaric magmatic chambers and liquated carbonatites. Consequently, the later-formed aillikites captured and mixed all varieties of xenocrysts.

Early Cretaceous fayalite-, ferrosilite-, and biotite-bearing rhyolitic porphyries in the Baishuizhai area, South China: Formation by fractional crystallization in the shallow crust

Fayalite- and ferrosilite-bearing felsic igneous rocks are a distinctive category of A-type granitic magmas, and the origins of these rocks have proved controversial. In addition, the shallow-crust high-silica rhyolitic magmas responsible for such rocks are considered to have higher viscosities than their plutonic equivalents, which casts doubt on whether fractional crystallization could have occurred during the evolution of these high-silica melts. Here, we report a study of earliest Early Cretaceous (145–142 Ma) fayalite- and ferrosilite-bearing rhyolitic porphyries (FFBRPs) and closely associated biotite-bearing rhyolitic porphyries (BBRPs) from the Baishuizhai area, Guangzhou, Guangdong Province, South China. The Baishuizhai suite provides an excellent opportunity to establish the magmatic origins and evolutionary processes responsible for the FFBRPs. Rocks from the Baishuizhai suite have SiO2 contents of 73.2–77.7 wt%, Na2O + K2O contents of 7.83–9.42 wt%, and Fe2O3T contents of 1.52–2.97 wt%. They have A-type granite features including mineral assemblages (euhedral fayalite and ferrosilite in addition to anhedral amphibole and biotite) and geochemical characteristics [e.g., high 10,000 × Ga/Al values (3.7–4.7), high FeOT/MgO ratios (13.0–34.8), and high Zr (245–514 ppm) and Nb (56.4–96.5 ppm) contents]. The rocks have slightly enriched in situ plagioclase Sr [(87Sr/86Sr)i = 0.7070–0.7076] and whole-rock Nd [εNd(t) = −2.3 to −2.0] compositions and depleted zircon Hf isotopic compositions [εHf(t) = −0.9 to +7.0] relative to chondrite, as well as higher zircon δ18O values (6.3‰–7.8‰) and intermediate in situ plagioclase Pb isotopic compositions [(206Pb/204Pb)i = 18.368–18.727, (207Pb/204Pb)i = 15.488–15.673, and (208Pb/204Pb)i = 38.049–38.801] compared with depleted mantle. We infer that the primary magmas of this rock suite were formed by mixing of mantle-derived magmas with subordinate (20%–50%) metasedimentary-rock-derived magmas. Fayalite and ferrosilite in the FFBRPs were most likely crystallized from dry, hot, and reduced magma in a lower (<16.5 km depth) chamber. The lower magma gradually evolved during ascent to a water-enriched magma in an intermediate chamber at a shallow depth (3–4 km), forming the FFBRPs (elevation: 129–168 m). Finally, the residual melts migrated upward and resided in an upper (<3 km depth) chamber, forming the BBRPs (elevation: 196–824 m). According to the established temporal–spatial distribution of Early Cretaceous A-type granites and adakitic rocks in South China, we suggest that the Paleo-Pacific plate underwent diachronous rollback, starting during the earliest Early Cretaceous. This rollback enhanced the degree of crust–mantle interaction in the Guangzhou area.

Highly alkaline electrokinetic extraction: Characteristics of chromium mobilization, conversion and transport in high alkalinity soil

In site chromium (Cr) contaminated soil characterized by high alkalinity and carbonate content, protons are not effectively targeted for Cr(III) mobilization but rather accelerate the reduction of easily transportable Cr(VI) within the acidification electrokinetic (EK) system. As an alternative, the highly alkaline extraction conditions (HAECs) maintained by anolyte regulation are explored owing to the ability to desorb strong binding Cr(VI) and form anionic Cr(III)-hydroxides (Cr(OH)4−, Cr(OH)52−). The results demonstrate that HAECs were more efficient in mobilizing ions in severe alkalinity and electrical conductivity soil compared to organic acid acidifying extraction conditions (OAECs). Simultaneously, a limited amount of soluble Cr(III) was produced; however, its transportation was hindered and more noticeable in the case of Cr(VI), displaying a distinct retention phase within the intermediate soil chamber. The antagonistic interplay between electromigration and electroosmotic flow was considered the main responsible factor. The conversion intensity of Cr(VI) to Cr(III) was inhibited at HAECs. The promising mobilization and low conversion intensity contributed to total Cr removal. At HAECs, enhanced electromigration and electroosmotic flow combined with a favorable oxidation environment may facilitate in situ delivery of oxidants, offering practical implications for the EK detoxification of high alkalinity site soil contaminated with Cr. The practicability of HAECs is likely to be enhanced when the cost-benefit balance of providing a simultaneous energy supply during site treatment is resolved.

Optimization of the intermediate chamber improves desalination performance in flow electrode capacitive deionization (FCDI): A comparative study

Flow electrode capacitive deionization (FCDI), a novel ion removal technology, is influenced by various factors such as electrode material properties, fluid flow rate, and device structure. In the FCDI system, the intermediate chamber is the core element where ions migrate towards the cathode and anode to complete the adsorption process. In this study, we designed a hollow plastic plate with channels (PP) and a hollow graphite plate with channels (GP) as the intermediate chamber, compare and study with conventional plastic mesh (PM) chambers. CFD simulations revealed that the newly designed PP and GP chambers significantly reduced the hydraulic stagnation zone. The results of the desalination experiments revealed that the desalination efficiency of the GP-FCDI was 1.5 and 1.9 times higher than that of the PP-FCDI and PM-FCDI, respectively. At the same time, in situ potential measurement (ISPM) was used to monitor the voltage drop of each component in FCDI, thereby accurately calculated the proportion of energy consumption in the intermediate chamber. The results indicate that the energy consumption of the intermediate chamber of GP-FCDI was 54 % less than that of PM-FCDI. The current work will help us provide new insights for the design and optimization of FCDI systems.

The effectiveness of vapor-injection for an inverter air-source heat pump compared with vapor-return

The vapor-injection assisted with air-source heat pump (ASHP) has become one of the focuses in the last decade. It can improve the heating performance of the ASHP system in low ambient temperatures by experiments. However, the vapor-injection is ineffective in moderate ambient temperatures owing to the high pressure of the compressor intermediate chamber. On the other side, the effectiveness of vapor-injection is rarely discussed. Based on experiments and the thermodynamic analysis method, this paper proposes an inverter air-source heat pump (IASHP) with vapor-injection and vapor-return. With the scope from −20 °C to7.0 °C for ambient temperature, it focuses on the heating performance of the prototype with different compressor frequencies for both vapor-injection and vapor-return modes. Moreover, the effectiveness of vapor-injection is discussed. The results show that the vapor-injection is superior to vapor-return for improving the heating performance of the prototype. Not only does the vapor-injection significantly affect refrigerant mass flow rate, but it also makes the relative entropy reduction (RER) of the compressor outlet decrease by 0.025–0.03 kJ/(kg·K). In the case of ambient temperature at −4.0 °C, the vapor-injection improves by 6.6 % and 3.4 % for heating capacity and COP of the prototype. Besides, the effectiveness of vapor-injection lies in the RER of the compressor outlet, which is suitable for vapor-injection using different refrigerants.

A «necklace» of large clusters of strategic raw materials over a stagnant oceanic slab in East Asia

&lt;p&gt;An analysis of geological-geophysical, metallogenic, geochronological, and seismic tomographic studies in territories joining Southeast Russia, East Mongolia, and Northeast China led to the conclusion that deep geodynamics significantly influenced the formation of highly productive ore-magmatic systems in the Late Jurassic-Early Cretaceous. This influence was likely manifested through the initiation of decompression processes around stagnant slab boundaries in the Late Mesozoic. Decompression and advection, which are particularly active near the natural boundaries of the slab, act as triggers for the intense interaction of under and over subduction asthenospheric fluids with adjacent sections of the mantle and for the directed upwelling of powerful flows of matter and energy into the lithosphere. These flows determine the locations of intermediate and peripheral magma chambers: Primary chambers in the lower lithosphere among the metasomatized mantle and lower crust and associated chambers in the middle and upper cratonized parts of the lithosphere. Large ore clusters containing noble metals (Au, PGE), uranium, fluorite, and Cu-Mo-porphyry deposits are associated with late- and postmagmatic derivatives of the emerging magma chambers over the frontal and peripheral (paleotransform) boundaries of a stagnant Pacific slab. These large Late Mesozoic ore clusters and districts form a distinctive "necklace" of strategic materials in East Asia.&lt;/p&gt;

Differentiation of Lamproitic Magma: Case Study of Mesozoic High-K Dikes of the Ryabinovyi Massif (Central Aldan)

Abstract ––Studies of the mineral–petrographic and geochemical compositions of high-potassic lamprophyric dikes of the Tobuk complex, manifested at the Ryabinovyi plutonic massif (Central Aldan Mesozoic magmatic province, Russia), have shown that these dikes compose a single fractionation series formed from a high-Mg lamproitic parental melt in an intermediate chamber. The composition of the rocks ranges from olivine–diopside–phlogopite and diopside–phlogopite lamproites through minettes to microsyenites and syenite–porphyry. Early crystallization of high-Mg olivine and chromite in an intermediate chamber could produce cumulative dunites similar to those of the Inagli intrusion. Crystallization of olivine and chromite was followed by cotectic crystallization of olivine and clinopyroxene, then that of clinopyroxene and phlogopite, and, finally, eutectic crystallization of Na-rich clinopyroxene, phlogopite, and K-feldspar. Crystallization and gravitational differentiation of lamproitic melt was complicated by silicate–carbonate immiscibility, which is texturally manifested in minettes as carbonate–silicate globules and interstitial calcium and magnesium carbonates. Furthermore, compositional zoning of Sr in apatite and Ba in phlogopite and K-feldspar is considered to have resulted from the immiscibility. Separation of the carbonate–fluorite melt fraction might have led to formation of the carbonatite and fluorite–carbonatite schlieren and gangues which have been described in drill cores from the Ryabinovyi massif. In most of the geochemical and mineralogic features, the Ryabinovyi massif lamproites are similar to the low-Ti lamproites of the Mediterranean postcollisional belt and northern Vietnam and differ from typical high-Ti within-plate lamproites.

Dynamic changes characteristics of the spermatozoon during the reproductive process of mud crab (Scylla paramamosain): From spermatophore formation, transportation to dispersion

To enhance comprehension of the destiny of the spermatozoon throughout the reproductive process of mud crab (Scylla paramamosain) is important for achieving large-scale artificial breeding of Scylla. The reproductive systems of sexually mature male and female mud crabs were studied, utilizing the histomorphological method. The spermatozoon traveled from testicular lobules through the seminiferous duct, into the anterior vas deferens (AVD) via the collecting duct. The spermatophore wall formed at the end of the AVD. During copulation, spermatophores stored in the median vas deferens (MVD) were transferred to the seminal receptacle through the posterior vas deferens (PVD), ejaculatory duct, and gonopod, with seminal plasma secreted by both MVD and PVD together. After mating, the sperm plug was formed within the seminal receptacle's ventral zone. At ovary stage Ⅲ, the spermatophore wall ruptured, and the sperm plug disappeared. Bundled sperm packets congregated into a dense mass, while a few spermatozoa dispersed along the intermediate chamber to the dorsal zone. At ovary stage Ⅳ, the dorsal zone also exhibited a dense sperm mass due to increased dispersal. At ovary stage Ⅴ, merely a modest portion of the dense sperm mass remained in the ventral zone, and the rest dissociated and dispersed within the seminal receptacle. Following ovulation, sperm mass remained in the ventral zone, re-dissociating and re-dispersing once ovarian development reached stage Ⅲ again. The phased dispersion supply mode of spermatozoa behind multiple ovipositions was unveiled. Furthermore, we observed the ultrastructural changes in the spermatozoon during the process of the capacitation, including operculum widening, actin-containing substance accumulation, and the density of chromatin in the nucleus decreased. As presented herein, the elucidation of the dynamic changes of the spermatozoon, as well as the pattern of spermatozoa supply, contributes significantly to our enhanced comprehension of the reproductive biology of Scylla.

Mineralogy and geochemistry of the Aushkul, Kamatal and Shartym granite massifs (Balbuk comlex, Southern Urals)

The article discusses the petrographic, mineralogical and petrogeochemical features of alkaline granites of the Balbuk complex in three massifs - Aushkul, Kamatal and Shartym. The rocks of the massifs are similar in structural and textural features and mineral composition: they are composed of acidic plagioclase, potassium feldspar, quartz and muscovite. In the Aushkul massif, phenocrysts of potassium feldspar, plagioclase, quartz and primary oligoclase are found in the groundmass, while in the Kamatal and Shartym massifs only phenocrysts of altered plagioclase and quartz are developed, and secondary albite is present in the groundmass. The existing differences in the geochemistry of the rocks of the Aushkul massif in comparison with Kamatal and Shartym (depleted in barium and enriched in niobium) may be associated with minor differences in the composition of magmas and with the peculiarities of their fractionation in intermediate chambers (fractionation of alkali feldspar and Nb-containing phases).

First data on rare earth mineralization in acid rock varieties of the Shatak complex (Southern Urals)

Research subject. Acid rock varieties of the Shatak complex were studied. Materials and methods. The reseach object included the previously unknown abundant mineralization represented by rare earth minerals. The concentration of petrogenic oxides was determined by the X-ray fluorescence method at the IG UFRC RAS (Ufa) using a VRA-30 spectrometer (Carl Zeiss, Germany) with an X-ray tube with a W-anode (30 kV, 40 mA). The amount of rare earth elements in the rocks of the studied area was determined by the ICP-MS method at the Central Research Institute of VSEGEI (St. Petersburg). The mineralogy was studied using a Tescan Vega Compact scanning electron microscope equipped with an Xplorer Oxford Instruments energy-dispersive analyzer (IG UFRC RAS, Ufa). Results. The studied rocks were diverse in chemical composition, varying from alkaline varieties (trachydacites) to low-alkaline rhyolites. These rocks belong to a highalumina type characterized by potassium specialization and a low agpaitic coefficient. It is assumed that the felsic varieties are subvolcanic formations, and the term “rhyolites” in this case characterizes the chemical composition of the rocks, but not their genesis. The amount of rare earth elements in the studied rocks is subject to significant fluctuations, varying from 60.81 g/t to 1625.39 g/t; moreover, their distribution is characterized by significant differentiation. In general, the rocks belong to a contrasting basalt-rhyolitic series, and their genesis is due to the differentiation of magma in the intermediate chamber. Numerous rare-earth minerals were found in the rocks, inlcuding allanite-(Ce), monazite-(Ce), monazite-(La), nioboeshinit-(Y), aeschinite-(Y), talena-(Dy), talena-(Nd), synchisite-(Ce) and Ce–La–Fe oxide. Conclusions. The presence of paragenetic associations of rare-earth minerals, such as allanite-(Ce) + aeschinite-(Y) + nioboaeschinite-(Y) and allanite-(Ce) + talena-(Dy) + talena-(Nd), indicate the formation of rare-earth mineralization in the course of a single process. The described type of mineralization has no analogues on the western slope of the Southern Urals, which substantiates the need for further research.

Automated solid phase DNA extraction on a lab-on-a-disc with two-degrees of freedom instrumentation

BackgroundLab-on-a-disc (LoaD) technology has emerged as a transformative approach for point-of-care diagnostics and high-throughput testing. The promise of integrating multiple laboratory functions onto a single integrated platform has significant implications for healthcare, especially in resource-limited settings. However, one of the primary challenges faced in the design and manufacture of LoaD devices is the integration of effective valving mechanisms. These valves are essential for fluid control and routing, but their intricacy often leads to complexities in design and increased vulnerability to failure. This emphasizes the need for improved designs and manufacturing processes without complex, integrated valving mechanisms. (96) ResultsWe describe a fully automated biological workflow and reagent actuation on a LoaD device without an integrated valving system. The Two Degrees-of-Freedom (2DoF) custom centrifuge alters the centre of rotation, facilitating fluid flow direction changes on the microfluidic platform through a custom programmed interface. A novel 360-degree fluid manipulation approach via secondary planetary gear motion enabled sequential assay reagent actuation without embedded valve triggering, with the addition of infinite incubation times and efficient use of platform realty. The simplified LoaD platform uses clever design, with intermediate flow chambers to avoid cross contamination between reagent steps. Notably, the optimized LoaD platform demonstrated a two-fold DNA yield at higher HEK-293 cell concentrations compared to commercially available spin-column kits. This significantly simplified LoaD platform successfully automated a common, complex workflow without inhibiting DNA purification. (129) SignificanceThis system exhibits the clever coupling of both 2DoF and centrifugal microfluidics to create an autonomous testing package capable of eradicating the need for complex valving systems to automate biological workflows on LoaDs. This automated system has outperformed commercially available DNA extraction kits for higher cell counts. The platform's elimination of valve requirements ensures unlimited sample incubation times and enhances reliability, making it a straightforward option for automated biological workflows, particularly in diagnostics. (73)

Three birds with one stone: Full-component recovery of strongly acidic arsenic complex wastewater via combining electro-redox and electrodialysis

Full-component green recovery of As-contained acid wastewater shows great prospect demanding on both urgent resource need and environment protection. In this work, we firstly constructed a three-chamber electrochemical system for full-component recovery of As-Cu acidic wastewater, combining electrochemical redox and electrodialysis techniques to recover metals and acids simultaneously. In which CeO2@CC and Cu plate electrode materials were selected and the middle chamber was separated by cation-exchange membrane (CEM) and anion-exchange membrane (AEM). In the anode chamber, 93.84% As(III) was oxidized and adsorbed by the CeO2@CC anode within 2 h. Meanwhile, 100% copper was reduced and deposited on the cathode. The pH of the intermediate chamber solution was reduced to 1.2. Besides, economic benefits and carbon emission accounting indicated that the system has better economic and environmental benefits for the full-component recovery of As-Cu strongly acidic wastewater. This work brings a new insight in future wastewater resource recovery and purification.

Petrological-mineralogical evolutional transformation of Cretaceous teschenite-tephrite, syenite-trachyte, and essexite-trachybasalt primary meltings (Carpathian, Caucasian and North TransBaikal regions)

&#x0D; &#x0D; &#x0D; This article discusses spatial and time distribution of Cretaceous teschenite-tephrite and essexite-trachybasalt complexes of the Carpathian, Caucasian, North TransBaikal regions. The main aim of the article is a comparative analysis of petrological-mineralogical features of similar complexes located in the Carpathians, North Caucasus and Transbaikal, Georgia in the Khojavand depression in the southeast of the Lesser Caucasus. Rocks of teschenite-tephrite, essexite-trachybasalt complexes were formed in the Cretaceous, early Eocene and Miocene. The differentiates of the considered complexes are localized in graben-like structures. The initial stage of graben formation is associated with the formation of rocks of the essexite-trachybasalt complex. The next stage of this process is associated with the formation of the teschenite-tephrite complex. According to stages of bedding and develop- ment of riftogenic graben structures, the essexite-trachybasalt complex formed first, at a mature stage – teschenite-tephrite one. At the initial stage high titanian olivine subalkaline basaltic melting occurred from the garnet-phlogopite lherzolite substratum. At the second stage – subalkaline picrite melting occurred from this substratum, which is primary for teschenite-tephrite and syenite-trachyte com- plexes. The metasomatized high-titanium phlogopite lherzolite substrate was subjected to melting twice. An earlier stage of melting of the substrate did not exceed 0.1%, from which a high-titanium olivine trachybasalt melt was separated. The second stage of melting of the substrate reached 10-12%. In this case, a subalkaline olivine picrite melt was formed. Evolution of primary meltings occurred in different-depth intermediate foci and intrusive chambers. The main factor in evolution along with controlling geodynamic regime was gravitational-crystallized differentiation. The identified mineral parageneses, starting from the early stage of the evolution of the subalkaline picrite melt to the late one, actually characterize the stages of crystallization of the noted melt in the intrusive chamber and intermediate chambers. The Eocene and Miocene teschenite-tephrite and essexite-trachybasalt complexes are characterized by a smaller areal distribution and petrographic diversity. Obviously, during this period, the intense activation of transverse magma-feeding faults contributed to the rapid uplift of the subalkaline picrite melt into the upper horizons of the earth’s crust.&#x0D; &#x0D; &#x0D;

A drum-like piezoelectric rotational energy harvester via magnetic beating

In this Letter, an indirectly excited approach of introducing an air-filled separation chamber is proposed to develop a drum-like piezoelectric rotational energy harvester (DL-PREH) via magnetic beating. The harvester delivers the external excitation to the piezoelectric transducer via the intermediate air chamber, and the electric output of transducer is induced by the air pressure inside the chamber. Thus, a high reliability can be guaranteed for the harvester under an unexpected excessive impact due to the air-filled separation zone. Moreover, the harvester can easily implement a resonant frequency tuning by altering the drum height to improve the rotation speed adaptability. Its potential applications as a sustainable power source to charge different capacitors and power commercial light-emitting diodes (LEDs) are demonstrated experimentally. The fabricated DL-PREH device can achieve a maximum output power of 10.63 mW with a drum height of 6 mm at the matching resistance of 24 kΩ. Also, it can light up at least 100 blue commercial LEDs in parallel. The designed harvester exhibits its good power generation capability and resonance frequency tunability.

Thermal state of the Siberian craton marginal zone at the time of Mesozoic kimberlitic magmatism within the Kuoika field (Yakutian diamondiferous province)

Research subject. Clinopyroxene xenocrysts from the heavy-mineral concentrates of 14 kimberlite bodies (western part of the field: Obnazhennaya, Rubin, Seraya, Vodorazdelnaya, Vtorogodnitsa, Antoshka; central part of the field: Sliudyanka, Skiff II; western part of the field: Irina, Noyabrskaya, Vechernyaya, Lyusya, Dianga and Zhila 79) of the Kuoika field (Yakutian diamondiferous province, Siberian craton). Aim. To reconstruct the mantle paleogeotherms Under the six kimberlite pipes (Vodorazdelnaya, Obnazhennaya, Vtorogodnitsa, Sliudyanka, Dianga, and Zhila 79) using two independent approaches. Materials and methods. The chemical composition of clinopyroxene xenocrysts was investigated and last equilibrium temperatures and pressures were estimated using single-crystal thermobarometry. The geothermal line fitting to the P-T data set was performed using two methods. The first method is based on the D. Hasterok and D.S. Champan model, and the second - on the D. McKenzie model. Results. The value of lithosphere thickness falls within the margin of error for the two methods, being also comparable with earlier reconstructions for the Vtorogodnitsa, Dyanga, and Obnazhennaya pipes. The obtained results indicate that, during the Mesozoic kimberlitic magmatism, the lithosphere thickness beneath the Kuoika field was about 200 km. Conclusion. The determined peculiarities of the chemical composition of clinopyroxene xenocrysts indicate heterogeneity of the lithospheric mantle composition. Different depths of transported mantle material for kimberlite pipes of the Kuoika field, which are coeval and are located a few km apart, may be related to peculiarities of kimberlite magma ascent to the surface and the presence of intermediate magma chambers. The eastern part of the Kuoika field contains more garnet and garnet-spinel peridotites compared to the central and western parts, which may indirectly indicate a greater diamondiferous potential of the eastern block, where the diamondiferous Dianga pipe is located. The absence of diamonds in other discovered pipes of the Kuoika field may be connected with the metasomatic enrichment of the lithospheric mantle in the area of the “diamond window”, which is confirmed by a large number of high-temperature clinopyroxenes at these depths.