Water Deposition Research Articles

Human health risk assessment of metal contamination in cereals and pulses in the mica mining areas of Jharkhand, India

This study was carried to investigate the contamination levels of heavy in food crops (rice, wheat, maize, and pulses) grown in the vicinity of the mica mine in Jharkhand, India. Except for Pb and Zn in select places, the metal concentrations in the food crops were below the maximum allowed levels for food in India. The principal component analysis identified three components that accounted for 71.3 % of the variability in the data. The components that were retrieved indicated that soil, irrigation water, and air dust deposition could be the sources of metals in the food crops. The estimated daily intake (EDI) and target hazard quotient (THQ) of food crop consumption were used to highlight the potential health concerns associated with metal exposure. In several samples, local individuals' daily intakes of Pb was greater than the WHO's recommended daily intakes of these heavy metals. Taking into account the geometric mean of metal concentrations in food crops samples from the, the hazard index (HI) for the consumers was 10.28 which is far above unity. Pb, Co, and As were the primary contributors to the potential non-carcinogenic risk. The HI ranged from 7.22 to 18.29 across different locations, indicating a significant health risk to the consumers of locally grown food crops in the vicinity of the mica mining areas.

Growth of zinc oxide nanowires by a hot water deposition method.

Recently, various methods have been developed for synthesizing zinc oxide (ZnO) nanostructures, including physical and chemical vapor deposition, as well as wet chemistry. These common methods require either high temperature, high vacuum, or toxic chemicals. In this study, we report the growth of zinc oxide ZnO nanowires by a new hot water deposition (HWD) method on various types of substrates, including copper plates, foams, and meshes, as well as on indium tin oxide (ITO)-coated glasses (ITO/glass). HWD is derived from the hot water treatment (HWT) method, which involves immersing piece(s) of metal and substrate(s) in hot deionized water and does not require any additives or catalysts. Metal acts as the source of metal oxide molecules that migrate in water and deposit on the substrate surface to form metal oxide nanostructures (MONSTRs). The morphological and crystallographic analyses of the source-metals and substrates revealed the presence of uniformly crystalline ZnO nanorods after the HWD. In addition, the growth mechanism of ZnO nanowires using HWD is discussed. This process is simple, inexpensive, low temperature, scalable, and eco-friendly. Moreover, HWD can be used to deposit a large variety of MONSTRs on almost any type of substrate material or geometry.

Formation mechanism and oil-bearing properties of gravity flow sand body of Chang 63 sub-member of Yanchang Formation in Huaqing area, Ordos Basin

Abstract Gravity flow sand body is an important reservoir for deep water deposition. The in-depth study of its formation mechanism and oil enrichment law can provide important guidance for oil and gas exploration in deep water areas. In this article, taking the deep-water gravity flow sand body of the Triassic Chang 63 sub-member in the Huaqing area as an example, the identification characteristics, formation mechanism, and oil-bearing characteristics of the gravity flow sand body are systematically discussed. The results show that sandy debris flow, turbidite flow, and mixed event flow present different superposition combination modes on vertical gravity flow deposition. The lithofacies of the gravity flow sandstone complex are mainly affected by lake level fluctuation, provenance supply, and hydrodynamic conditions. According to the formation conditions, sedimentary types. and distribution characteristics of deep water gravity flow sand bodies, a three-dimensional sedimentary mode of deep water gravity flow sand bodies is established. It is found that the physical and oil-bearing properties of the sandy debris flow sand body are better than those of the turbidity flow sand body. The reason is that the proportion of debris in the sand body of sandy debris flow is high, and the content of debris particles is generally greater than 70% according to the statistics of thin sections, which is conducive to the formation of pores. Second, sandy debris flow belongs to block transport, and the mixing of lithology is not sufficient in the process of block flow transport, so some pores will be preserved. Finally, gravity flows, which are dense at the beginning, become less dense later as detrital sediments unload, allowing them to be transported to distant regions. Therefore, the monolayer thickness of the sandy debris flow sand body is large (generally greater than 0.5 m), and the particle size of the debris ranges from 0.03 to 0.3 mm. Finally, the physical and oil-bearing properties of the sandy clastic flow sand body are better than those of the turbidity flow sand body.

Hermeneutic Cartography for the Restitution of a Lost Antique Seaport

This article deals with the reconstruction of an ancient seaport in the town of Bejaia, known as Muslubium Horrea. This settlement, ignored by the official historiography, would nevertheless have played an important role in wheat exports and trade with the Roman port of Ostia. Moreover, of all the ancient ports known to date, the Algerian coast has only two port warehouses, and Muslubium Horrea is the only granary belonging to the Roman province of Mauretania Sitifensis (400AD). The methodology adopted to locate and reconstruct the topography and the settlement’s structures is based on the concept of cartographic hermeneutics. The compilation of existing historical accounts and the interpretation derived from the superimposition of ancient geographical maps and 19th century archaeological and geological maps identified all the natural resources necessary for its construction, in particular the abundance of water sources and deposits of geomaterials for construction (clay, stone, gypse, marble, etc.). These data were confirmed by field and photogrammetric surveys, resulting in a map showing the archaeological context of the Muslubium Horrea port and the remains of structures still visible today. The approach adopted allowed to delineate the size of the port site and scale the structures that make it up, as well as identify the water supply source and its primitive topography prior to its establishment.

Fractal dimension and lacunarity measures of glioma subcomponents are discriminative of the grade of gliomas and IDH status.

Since the overall glioma mass and its subcomponents-enhancing region (malignant part of the tumor), non-enhancing (less aggressive tumor cells), necrotic core (dead cells), and edema (water deposition)-are complex and irregular structures, non-Euclidean geometric measures such as fractal dimension (FD or "fractality") and lacunarity are needed to quantify their structural complexity. Fractality measures the extent of structural irregularity, while lacunarity measures the spatial distribution or gaps. The complex geometric patterns of the glioma subcomponents may be closely associated with the grade and molecular landscape. Therefore, we measured FD and lacunarity in the glioma subcomponents and developed machine learning models to discriminate between tumor grades and isocitrate dehydrogenase (IDH) gene status. 3D fractal dimension (FD3D) and lacunarity (Lac3D) were measured for the enhancing, non-enhancing plus necrotic core, and edema-subcomponents using preoperative structural-MRI obtained from the The Cancer Genome Atlas (TCGA) and University of California San Francisco Preoperative Diffuse Glioma MRI (UCSF-PDGM) glioma cohorts. The FD3D and Lac3D measures of the tumor-subcomponents were then compared across glioma grades (HGGs: high-grade gliomas vs. LGGs: low-grade gliomas) and IDH status (mutant vs. wild type). Using these measures, machine learning platforms discriminative of glioma grade and IDH status were developed. Kaplan-Meier survival analysis was used to assess the prognostic significance of FD3D and Lac3D measurements. HGG exhibited significantly higher fractality and lower lacunarity in the enhancing subcomponent, along with lower fractality in the non-enhancing subcomponent compared to LGG. This suggests that a highly irregular and complex geometry in the enhancing-subcomponent is a characteristic feature of HGGs. A comparison of FD3D and Lac3D between IDH-wild type and IDH-mutant gliomas revealed that mutant gliomas had ~2.5-fold lower FD3D in the enhancing-subcomponent and higher FD3D with lower Lac3D in the non-enhancing subcomponent, indicating a less complex and smooth enhancing subcomponent, and a more continuous non-enhancing subcomponent as features of IDH-mutant gliomas. Supervised ML models using FD3D from both the enhancing and non-enhancing subcomponents together demonstrated high-sensitivity in discriminating glioma grades (~97.9%) and IDH status (~94.4%). A combined fractal estimation of the enhancing and non-enhancing subcomponents using MR images could serve as a non-invasive, precise, and quantitative measure for discriminating glioma grade and IDH status. The combination of 2-hydroxyglutarate-magnetic resonance spectroscopy (2HG-MRS) with FD3D and Lac3D quantification may be established as a robust imaging signature for glioma subtyping.

Water Quality Modeling of Wastewater Discharges for Prediction of Sediment Transport and Deposition in Surface Water

Sediment deposition in surface water bodies can have a range of significant impacts, affecting everything from the aquatic ecosystem to water quality and infrastructure. It can affect the availability of food sources for aquatic organisms; and change the physical structure of habitats, such as riverbeds and lake bottoms. It can equally smother aquatic plants and animals, leading to a decline in biodiversity. A model of the governing equations of particle motion and fluid flow was developed with COMSOL Multiphysics 5.3a. With a coefficient of determination of 0.99, the model result demonstrated good agreement after result validation using experimental data. According to study findings, sediments in the study area, Ele River move more slowly than sediments in the midstream which causes a high deposition of sediments at the river banks. This sediment deposition affects the irrigation system for crop production considering the ability of the sediments to block sprinkler nozzles which limits it from supplying sufficient water for the production of crops.

Mechanical deviation in 3D-Printed PLA bone scaffolds during biodegradation

Large or carcinogenic bone defects may require a challenging bone tissue scaffold design ensuring a proper mechanobiological setting. Porosity and biodegradation rate are the key parameters controlling the bone-remodeling process. PLA presents a great potential for geometrically flexible 3-D scaffold design. This study aims to investigate the mechanical variation throughout the biodegradation process for lattice-type PLA scaffolds using both experimental observations and simulations. Three different unit-cell geometries are used for creating the scaffolds: basic cube (BC), body-centered structure (BCS), and body-centered cube (BCC). Three different porosity ratios, 50 %, 62.5 %, and 75 %, are assigned to all three structures by altering their strut dimensions. 3-D printed scaffolds are soaked in PBS solution at 37 °C for 15, 30, 60, 90, and 120 days both unloaded and under dead load. Water absorption, weight loss, and compression stiffness are measured to characterize the first-stage degradation and investigate the possible influences of these parameters on the whole biodegradation process. The strength reduction stage of biodegradation is simulated by solving pseudo-first-order kinetics-based molecular weight change equation using FEA with equisized cubic (voxel-like) elements.For the first stage, mechanical load does not have a statistically significant effect on biodegradation. BCC with 62.5 % porosity shows a maximum water absorption rate of around 25 % by the 60th day which brings an advantage in creating an aquatic environment for cell growth. Results indicate a significant water deposition inside almost all scaffolds and water content is determined to be the main reason for the retained or increased compression stiffness. A distinguishable stiffness increase in the initial degradation process occurs for 75 % porous BC and 50 % porous BCC scaffolds. Following the quasi-stable stage of biodegradation, almost all scaffolds lost their rigidity by around 44–48 % within 120 days based on numerical results. Therefore, initial stiffness increase in the quasi-stable stage of biodegradation can be advantageous and BCC geometry with a porosity between 50% and 62 % is the optimum solution for the whole biodegradation process.

Harnessing the Energy Potential of Associated Gases from Geothermal Water Deposits in Micro-Cogeneration Power Plants

Harnessing the Energy Potential of Associated Gases from Geothermal Water Deposits in Micro-Cogeneration Power Plants

54 Development of an equine metabolism model to describe post-absorptive nutrient dynamics

Abstract Nutrition modelling is instrumental to modern feed formulation and diet optimization across livestock sectors. Mechanistic models of nutrient digestion, absorption, and metabolism are implemented in industry as ‘decision support systems’, and in academia to summarize and examine our cumulative biological knowledge, identify knowledge gaps and test/evaluate hypotheses. However, comparatively less progress in this field has been made in the equine sector. This limits the ability of the equine sector to address complex challenges such as interactions between equine nutrition, management, health, and welfare. To address this gap, a first iteration of a dynamic, deterministic, mechanistic model describing postabsorptive nutrient dynamics for equines has been developed. Model coding and development was performed using Python with specific libraries for mathematical equations and integration. This model was developed primarily based on extant published mechanistic models of protein and energy metabolism in other species. The present model simulates the partitioning of ingested nutrients into digested nutrients, through intermediary metabolism and ultimately to growth and deposition of protein, fat, water, and ash into the body compartments. As shown in Figure 1, the model takes digested nutrients (protein, fat, starch, glucose, volatile fatty acids) as inputs and contains 12 state variables divided into metabolite pools (amino acids, fatty acids, glucose, glycogen, acetyl-CoA, ATP), and body constituent pools (muscle protein, bone protein, hide protein, viscera protein, body fat, body ash). Ingested feed is partitioned into digested nutrients using digestibility coefficients from extant equine literature, and indigestible nutrients are excreted. Meta-analysis was used to develop empirical equations to predict VFA concentrations in the hindgut. VFA absorption is estimated using Michaelis-Menten kinetics including the pH and hindgut volume, assumed as a constant value for a mature horse Acetyl-CoA, a key intermediary metabolism pool, is produced from amino acid, glucose, and fatty acid catabolism and is consumed for maintenance requirements, which is accounted for in an ATP pool. The ATP pool is a ‘zero pool’, which balances the ATP producing and -consuming reactions in the model, with any remaining ATP balance required being pulled from the acetyl-CoA pool. Turnover of protein and fat is represented by differences in accretion and catabolism. Work is ongoing to evaluate the developed model for model performance using data extracted from the literature. The model will be trained and subsequently evaluated using equine studies in three main areas: growth and body composition, protein turnover and nitrogen balance, and energy metabolism. Developing this model for the equine sector will stimulate and assist in defining future research priorities, inform revisions to the nutrient requirements of horses, increase understanding of metabolic processes as well as related disorders, reduce waste via increased focus on precision feeding and support the development of new products and services to improve equine health.

Quantitative assessment of Cd sources in rice grains through Cd isotopes and MixSIAR model in a typical e-waste dismantling area of Southeast China

Identification of Cd sources and quantification of their contribution to rice grain Cd is crucial for controlling accumulation of this toxic metal in rice grains. However, accurate assessment of the contribution of different Cd sources to grain Cd concentration in rice under actual field conditions is a challenge. In this study, we determined Cd concentration and their isotopic compositions in rice grains with respect to three potential Cd sources around an e-waste dismantling area in Taizhou City, Zhejiang Province, China. Results demonstrated that average Cd concentrations in grains, surface soils, atmospheric deposition and surface water were 0.32, 0.91, 1.99 mg kg−1 and 2.02 μg L−1, respectively. The δ114/110Cd values of grains, surface soils, surface water and atmospheric deposition ranged from 0.00 ‰ to 0.31 ‰, −0.21 ‰ to 0.14 ‰, −0.04 ‰ to 0.47 ‰, and − 0.25 ‰ to −0.18 ‰, respectively. The MixSIAR model indicated that contribution of soils, irrigation water and atmospheric deposition to grain Cd was 56.8 %, 24.8 % and 18.4 %, respectively, demonstrating soils as the major source of grain Cd in the study area. This study also highlighted significant contribution of irrigation water and atmospheric deposition to Cd concentration in rice grains. The Cd isotopic analysis provides a practical approach for source apportionment of grain Cd and data support for controlling Cd accumulation in rice around the e-waste dismantling area.

SEDIMENTATION IN HYDROELECTRIC POWER TURBINES

The primary cause of erosive wear and energy loss is friction, and reportedly, one-third of the world’s energy resources go to overcome friction by several methods. The presence of deposits in water is a common problem in mountainous regions and some Ukrainian hydroelectric power stations. Hydro turbines face serious issues related to erosion from deposits during operation. Erosive wear occurs due to the impact of solid particles against a solid surface. The current environment contains particles whose velocity is sufficient to damage metal surfaces. Various researchers have conducted numerous studies to minimise the effect of deposit erosion in multiple locations of Francis turbine components (FT). For this purpose, they performed field investigations, experimental measurements, empirical modelling, computational fluid dynamics (CFD) work, and other methods. Various empirical models have been used to describe erosive wear in terms of material and fluid properties. They established that, for ductile materials, maximum erosion occurs at an impact angle of 30°, whereas for brittle materials, it occurs in the range of 80–90°. In the literature, various experimental methods are available to quantitatively assess slurry erosion, such as the rotating disk apparatus (RDA), slurry tank testing, jet erosion testing, and rotating drum testing. Due to manufacturing technologies used in mechanical processing processes, the exposed surface has a certain absolute roughness that increases during machine operation due to abrasion or erosion. Therefore, surface texture leads to increased energy efficiency losses during operation. Technological advancements have facilitated the widespread use of computational tools to address deposit erosion issues. In recent decades, numerical methodology has been a widely used and effective tool, yielding tangible and reliable results. This study examines potential methods for detecting and reducing deposits. This type of erosion depends on flow characteristics, surface properties, and properties of the eroding material. The article provides comprehensive information on sedimentation (deposits) causing wear in hydraulic turbines. Keywords: hydroelectric turbine, sedimentation erosion, computational fluid dynamics, fluid-structure interaction.

Evolution mechanism of microbial community structure and metabolic activity in aquatic nutrient-poor sedimentary environments driven by 17β-estradiol pollution.

17β-Estradiol (E2) is a novel micro-pollutant that is widely distributed in aquatic sediments and has a universal toxicological effect on aquatic organisms. However, its ecological impact on aquatic microorganisms is not yet clear. In this study, we designed a simulation system for oligotrophic water deposition in the laboratory, analyzed the impact of different concentrations of E2 pollution on the carbon metabolism activity (carbon gas emission rate) of water microorganisms. Based on high-throughput sequencing results, we revealed the impact of E2 pollution on the community structure succession and metabolic function of bacteria, archaea, and methanogens in the simulated system, explored the impact mechanism of E2 pollution on microbial carbon metabolism in water bodies. Our results suggested that E2 significantly impacts the bacterial and archaeal community rather than the methanogen community, thereby indirectly inhibiting methane production. The achievements will bridge the theoretical gap between estrogen metabolism and carbon metabolism in sedimentary environments and contribute to enriching the ecological toxicology theory of steroid estrogen.

Distribution, sources, ecological and human health risks of organic ultraviolet filters in coastal waters and beach deposits in Hainan, China

Organic ultraviolet filters (OUVFs) are extensively incorporated into both cosmetic items and industrial products and have been commonly found in water ecosystems. This study aims to examine the environmental levels, sources, ecological and human health risks of 14 commonly used OUVFs both in coastal water and beach deposit samples collected from the nearshore regions of Hainan Island and the South China Sea. This is first study highlighting the contamination of OUVFs in Hainan Island and utilizing economic and tourism data to confirm the potential source of OUVF pollution in costal aquatic and coastal ecosystem. Along the coastal tourist regions of Hainan Island, the median concentrations in coastal waters and beach deposits of these OUVFs fall within the range from 1.2 to 53.2 ng/L and 0.2–17.0 ng/g dw, respectively. In coastal water and beach deposit, the concentration of BP-3 was the highest, with median concentrations of 53.2 ng/L and 17.0 ng/g dw, respectively. Regarding human health risks, the daily intake of all 14 OUVFs through swimming was found to be 40–48 ng/kg/day. Ecological risk assessment indicates that BP-3 presents a medium risk for marine microalgae with a concurrent low risk for corals. The correlation analysis underscores a substantial interrelation of OUVFs in both coastal waters and beach deposits with various economic indicators, including annual rainfall, overnight tourists, total hotel rooms (unit), room occupancy rate, and sewage treatment capacity.

Temperature Variations in Deep Thermal Well LZT-1 in Lądek-Zdrój (Bohemian Massif; SW Poland)—Evidence of Geothermal Anomaly and Paleoclimatic Changes

The thermal water deposit in Lądek-Zdrój (SW Poland) occurs in fractured reservoir rocks, and its hydrogeological regime is controlled by the features of the local geology and lithology of the hosting crystalline complexes, mainly impermeable high-grade metamorphosed mica schists and gneisses. The fractured thermal water aquifer is confined by a thrust fault-type aquitard that creates artesian pressure and, therefore, the water intakes and natural springs in Lądek Zdrój provide spontaneous outflow. Classical geothermometers yield an estimation of reservoir temperatures that ranges from 50 to 70 °C, with a maximum of 88 °C. The heat flux (HF) value of the Lądek-Zdrój region is 64 mW/m2. The new borehole, LZT-1, is in the border zone of a local thermal anomaly with a geothermal degree of 25–27 m/°C. The estimated temperature at the bottom of the LZT-1 borehole, under thermal equilibrium conditions, ranges between 70 °C and 80 °C. A stream of heated waters from the deep system flows from the recharge areas, shaping the local geothermal anomaly and thus influencing the thermal conditions in the Lądek-Zdrój area. The activation of this water circulation system occurred in the Pleistocene.

The sedimentary environment and main controlling factors of organic matter enrichment of Carboniferous-Permian marine-continental transitional shale in Kaiping syncline

The shale from the Carboniferous and Permian Taiyuan–Shanxi Formation in Kaiping syncline has good prospects for shale gas exploration and development. To understand the evolutionary characteristics of the sedimentary environment in this area and their relationships with organic matter enrichment. Shale samples from the Taiyuan-Shanxi in Well KP1 were selected as research objects, followed by organic geochemical research, elemental geochemical analysis, and numerical analysis. The results show that the sedimentary period of the Shanxi Formation was marked by a medium productivity level. The sedimentary water column was composed of brackish water and seawater deposits in an anoxic reduction environment. The Taiyuan Formation shale was characterized by a medium level of paleoproductivity. The sedimentary water column was composed of brackish water deposits in an anoxic reduction environment. According to the linear correlation analysis of paleoenvironmental conditions and TOC content. This study suggests that ancient water salinity is the main factor controlling the enrichment of organic matter in the sedimentary stage of the Taiyuan-Shanxi Formation.

Pyritic stromatolites from the Paleoarchean Dresser Formation, Pilbara Craton: Resolving biogenicity and hydrothermally influenced ecosystem dynamics.

This study investigates the paleobiological significance of pyritic stromatolites from the 3.48 billion-year-old Dresser Formation, Pilbara Craton. By combining paleoenvironmental analyses with observations from well-preserved stromatolites in newly obtained drill cores, the research reveals stratiform and columnar to domal pyritic structures with wavy to wrinkly laminations and crest thickening, hosted within facies variably influenced by syn-depositional hydrothermal activity. The columnar and domal stromatolites occur in strata with clearly distinguishable primary depositional textures. Mineralogical variability and fine-scale interference textures between the microbialites and the enclosing sediment highlight interplays between microbial and depositional processes. The stromatolites consist of organomineralization - nanoporous pyrite and microspherulitic barite - hosting significant thermally mature organic matter (OM). This includes filamentous organic microstructures encased within nanoporous pyrite, resembling the extracellular polymeric substance (EPS) of microbes. These findings imply biogenicity and support the activity of microbial life in a volcano-sedimentary environment with hydrothermal activity and evaporative cycles. Coupled changes in stromatolite morphology and host facies suggest growth in diverse niches, from dynamic, hydrothermally influenced shallow-water environments to restricted brine pools strongly enriched in from seawater and hydrothermal activity. These observations, along with S stable isotope data indicating influence by S metabolisms, and accumulations of biologically significant metals and metalloids (Ni and As) within the microbialites, help constrain microbial processes. Columnar to domal stromatolites in dynamic, hydrothermally influenced shallow water deposits likely formed by microbial communities dominated by phototrophs. Stratiform pyritic structures within barite-rich strata may reflect the prevalence of chemotrophs near hydrothermal venting, where hydrothermal activity and microbial processes influenced barite precipitation. Rapid pyrite precipitation, a putative taphonomic process for preserving microbial remnants, is attributed to microbial sulfate reduction and reduced S sourced from hydrothermal activity. In conclusion, this research underscores the biogenicity of the Dresser stromatolites and advances our understanding of microbial ecosystems in Earth's early history.

TRACE ELEMENTS IN THE GROUNDWATER OF THE NEMYRIV DEPOSIT (UKRAINE)

The data obtained and published to date by experts in various fields indicate that there are no absolutely harmful or absolutely beneficial trace elements, the only question is their concentration and form in natural waters (including groundwater). The forms of occurrence in natural waters are particularly important for elements that may have different degrees of oxidation (e.g., arsenic, manganese) or a high ability to form complexes with water anions (e.g., nickel). In addition, the possible positive and negative effects of biological exposure to drinking water that meets the quality criteria but has slightly elevated levels of trace elements (the so-called “chronic” effect) are currently being actively discussed. The aim of this study is to determine the speciation of biologically active trace elements in the waters of the Nemyriv drinking water deposit in the Southern Bug River basin by geochemical modelling. The modelling was performed using the PHREEQC software. Trace elements found in water in concentrations measured by analytical methods are considered in this paper. The data on the content of 7 elements (As, Mn, Sr, Ni, P, Si and F) in the water of 6 wells in the Skifska area (3 wells in the ravine and 3 wells along the Ustia River) were analysed. The concentrations of Sr, Ni, P and F in the water of the wells considered in the Nemyriv drinking water deposit do not exceed the MPC. The concentration of As exceeds the MPC. Mn concentrations in the wells located in the ravine do not exceed the MPC, but significant excesses are observed in the wells located along the Ustia River. Based on the mineral composition of the rocks, the results of geochemical modelling, and the different supply mechanisms of the wells located in the ravine and along the river, it can be concluded that the manganese is of anthropogenic origin. None of the water in the Skifska area under consideration meet the water quality requirements in terms of the total specific content of pollutants of the first and second hazard classes. The main reason for this discrepancy is the increased concentration of arsenic in the water. However, this is in the relatively safe form of As(V). Phosphorus and arsenic concentrations are largely determined by co-precipitation with iron minerals. Fluorine behaves like a classical halogen in the well water of the Skifska area and is in oxidation state-1, and the main source of fluorine is biotite and fluorite. Strontium and manganese in the well waters of the Skifska area of the Nemyriv deposit are in oxidation degree +2, mainly in the form of Me2+ cations. The manganese occurrence in such a oxidation degree indicates its potential bioavailability, so it is necessary to carry out additional analytical studies to determine the concentrations of Mn and organic compounds, perform repeated geochemical modelling, assess the hazard of these waters to humans and develop additional water treatment measures.

Deposition of Water and Emulsion Hollow Droplets on Hydrophilic and Hydrophobic Surfaces

The deposition of spray droplets is a hot topic in the field of plant protection. The air-induction nozzle, which is commonly used in agricultural spray, can produce droplets containing bubbles. However, few studies have addressed the deposition of hollow droplets. In the present study, we used experimental and numerical methods to investigate the deposition of hollow droplets. Three kinds of liquid—water, oil-based emulsion and organosilicon—were used to produce hollow droplets, and the diameter of droplets varied from 3 to 4.5 mm. Both hydrophilic and hydrophobic surfaces were selected as deposition targets. The results show that the deposition of hollow droplets can generate a central jet, which is similar to the Wortington jet. High deposition velocity and the large bubble volume were responsible for the large attainable height of the central jet. On the hydrophilic surface, for water hollow droplets with Weber number (We) ranging from 350 to 391, the central jet began to break up as the bubble fraction of the hollow droplet reached 0.15. Based on the numerical results, it was found that the internal pressure difference between the bottom liquid and the air cavity leads to the formation of the central jet. The bubble volume and impact velocity were both positively correlated with the internal pressure difference. The oil-based emulsion promoted the adherence of the hollow droplet by lubricating the hydrophobic surface. The oil-based emulsion hollow droplets shifted from rebounding to adhering on the hydrophobic surface as the emulsion concentration reached 0.4%.

Sedimentary basins, hydrocarbons, graphite, coal, and Cu-Au deposits - from Mongolia to the Pacific margin: Interplay between the ubiquitous orthogonal fracture network and Global Wrench Tectonics

Mongolia is exceptionally rich in coal and copper-gold resources - with world-class deposits like Tavan Tolgoi, Oyu Tolgoi and Erdenet. Thus, the mining industry has a crucial importance for the national economy, yet most of the country remain very underexplored. Within today's global tectonics, an acceptable understanding of metal enrichments - including leaching, the internal hydrostatic-hydraulic pumping system, and surface emplacement mechanisms - has remained unresolved. However, a broader view of the structural situation in the Mongolia-China region shows a close link between orientation of elongate sedimentary basins, important mineral belts, and the fundamental orthogonal fracture/fault system. In the east the tectonic trend is dominantly northeast, while it is northwest in western areas. The main east Mongolian graphite deposits have northeast structural trends like numerous regional Cu and Au belts. A new theory of the earth, Global Wrench Tectonics, offers an exciting approach to better understanding the various facets of Earth's geological history and its surface resources. Earth’s degassing, dynamo-tectonic consequences, inertia-driven crustal wrench tectonics, as well as surface products such as water, hydrocarbons and ore deposits are given a coherent system explanation. Many hydrocarbons are products from the interior of our slowly degassing Earth, with massive hydrocarbon fields such as Songliao and the Yamal megaproject producing from the basement. Crustal thinning in the Songliao region is about the same as in southeast Mongolia, suggesting that they may have had similar degassing and crustal evolution histories. As such, it is not unlikely that the underexplored Mesozoic basins of southeast Mongolia - particularly at the deepest levels and/or in the adjacent crystalline basement - may have important hydrocarbon potential.

Macro-characteristics and micro-mechanisms of Na2SO4 precipitation dissolved by KNO3 molten salt in a continuous supercritical water system

This work aims to explore the ability of molten salt to solve salt deposition in supercritical water (SCW) related technologies including supercritical water oxidation and supercritical water gasification, with KNO3 and Na2SO4 as examples. In the pure KNO3 solution, the two-phase layering of high-density KNO3 molten salt (settling at the reactor bottom) and low-density saturated KNO3-SCW salt solution (flowing out at the top outlet of the reactor) was formed in a kettle-reactor with about 6.5 ratio of depth to inner diameter, thereby improving the accuracy of measured solubilities. The precipitation macro-characteristics of mixed KNO3 and Na2SO4 in SCW were investigated under different feed concentration conditions. The results showed that Na2SO4 deposition on the reactor sidewall could be reduced by more than 90 % when the mass ratio of KNO3 to Na2SO4 in the feed was only 0.167. No visible salt deposition was observed on the sidewall when the ratio was 0.374. All solid deposited salts were converted into the liquid molten salt as the ratio reached 3.341, and thus could easily flow out of the reactor, without plugging. ‘Molten salt dissolution’ mechanism may provide a more plausible explanation for mixed KNO3 and Na2SO4 in SCW. In addition, the precipitation micro-mechanisms of mixed KNO3 and Na2SO4, and the critical conditions of avoiding sidewall deposition and reactor plugging were proposed. This work is valuable for overcoming the salt deposition problem in SCW-related technologies.