Search Results (15)

The Shuixie Cu–Co polymetallic orefield, located in western Yunnan Province (southeastern margin of the Qinghai–Tibet Plateau), is renowned for its Cu–Co mineralization. A recent resource reassessment identified Sb–Au and Cu–Co–Bi (Sb–Au) orebodies as genetically associated with primary Cu–Co mineralization. The mineralization characteristics and microscopic observations indicate that gold mineralization in the Sb–Au orebodies follow a pulsating fluid injection model. The model includes four pulses: (1) euhedral gold-poor pyrite (PyI₁) precipitation; (2) margin-parallel growth of gold-rich pyrite (PyI₂) on PyI₁; (3) continued growth of gold-rich pyrite (PyI₃) along PyI₂; and (4) outermost concentric gold-rich pyrite (PyI₄) formation. This study examined gold-bearing pyrite in orebodies and host rocks. In situ laser ablation inductively coupled plasma mass spectrometry (LA–ICP–MS) analysis of pyrite and inductively coupled plasma mass spectrometry (ICP–MS) whole-rock trace element analysis were conducted to track the ore-forming fluid evolution. Compared with CI chondrite, pyrites from all pulses were enriched in LREEs over HREEs. The pyrite REE distribution curves exhibited right-skewed patterns, reflecting LREE enrichment. The Hf/Sm, Nb/La, and Th/La ratios were generally below 1, indicating high-field-strength element depletion. These results suggest a Cl-rich, F-poor ore-forming fluid. The pyrite trace elements showed enrichment in the chalcophile elements (e.g., Cu and Pb) and exceptionally high Bi levels compared with the continental crust. The chalcophile elements (e.g., Zn and Cd) were depleted, whereas iron-group elements (e.g., Co) were enriched and Ni was depleted. The pyrite δCe values (0.87–1.28, mean = 1.01) showed weak anomalies, indicating a reducing ore-forming environment. The δEu values of pyrite during pulses 1 to 4 ranged widely, from 0.2–3.01 (mean of 1.17), 0.27–1.39 (0.6), and 0.41–1.40 (0.96) to 0.4–1.36 (0.84), respectively, suggesting an initial temperature decline and subsequent increase in the ore-forming fluid. Significant variations were found in the Y/Ho, Zr/Hf, and Nb/Ta ratios across pulses, indicating the potential involvement of high-temperature hydrothermal fluids or late-stage alteration during ore formation. The Y/Ho ratio of pyrite overlapped most closely with that of the continental crust of China, indicating a close relationship between the ore-forming fluids and the crust. Full article

Chelidonium majus L. is a species with a wide medicinal use, commonly found in anthropogenically degraded habitats, forest edges, and urban parks. This study aimed to determine the chemical composition of the leaves, stems, and roots of Ch. majus and the soil in its rhizosphere in terms of the content of the main elements (Fe, Ca, P, Mg, Al, Na, K, S), trace elements and rare earth minerals (Ti, Mo, Ag, U, Au, Th, Sb, Bi, V, La, B, W, Sc, Tl, Se, Te, Ga, Cs, Ge, Hf, Nb, Rb, Sn, Ta, Zr, Y, Ce, In, Be, and Li), and their comparison in the parts analyzed. The study was conducted in five urban parks in southern Poland in a historically industrialized area. The results showed that Ca has the highest content among the macroelements. Its leaf content ranges from 24,700 to 40,700 mg·kg⁻¹, while in soil, it ranges from 6500 to 15,000 mg·kg⁻¹. In leaves, low values of Al (100–500 mg·kg⁻¹) and Na (100 mg·kg⁻¹) were found in comparison to the other elements tested, while high values of Al (5100–9800 mg·kg⁻¹) were found in soils. Among the macroelements in the Ch. majus stems, K showed the highest concentration (>100,000 mg·kg⁻¹), while the Ca content was 3–4 times lower in the stems than in the leaves. Rhizomes of Ch. majus accumulate the most K and Ca, in the range of 22,800–29,900 mg·kg⁻¹ and 5400–8900 mg·kg⁻¹, respectively. Fe and Al in all locations have higher values in the soil than in the tissues. In turn, the content of Ca, P, Mg, K, and S is higher in plants than in the soil. Determining the elemental content of medicinal plants is important information, as the plant draws these elements from the soil, and, at higher levels of toxicity, it may indicate that the plant should not be taken from this habitat for medicinal purposes. Full article

The assessment of soil contamination in the vicinity of integrated siderurgical plants is of outmost importance for agroecosystems and human health, and sensitive techniques should be employed for accurate assessment of chemical elements (metals, potential toxic elements, rare earths, radioelements) in soil and further evaluation of potential ecological and safety risk. In this paper a total of 45 major, minor and trace elements (Al, As, Au, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Cu, Dy, Eu, Fe, Hf, Hg, I, K, La, Mg, Mn, Mo, Na, Nd, Ni, Pb, Rb, Sb, Sc, Sm, Sn, Sr, Ta, Tb, Th, Ti, Tm, U, V, W, Y, Yb, Zn and Zr) were quantified in soils located around a large siderurgical works (Galati, SE Romania) using instrumental neutron activation analysis (INAA) in combination with X-ray fluorescence (XRF) and inductively coupled plasma mass spectrometry (ICP–MS). The statistical analysis results and vertical distribution patterns for three depths (0–5 cm, 5–20 cm, 20–30 cm) indicate inputs of toxic elements in the sites close to the ironmaking and steelmaking facilities and industrial wastes dumping site. For selected elements, a comparison with historical, legislated and world reported concentration values in soil was performed and depth migration, contamination and toxic risk indices were assessed. The distribution of major, rock forming elements was closer to the Upper Continental Crust (UCC), and to the Dobrogea loess, a finding confirmed by the ternary diagram of the incompatible trace elements Sc, La and Th, as well as by the La to Th rate. At the same time, the La/Th vs. Sc and Th/Sc vs. Zr/Sc bi-plots suggested a felsic origin and a weak recycling of soils’ mineral components. Full article

The contents of 49 trace elements in sub-bituminous Pernik coals and their waste products from preparation and combustion processes were investigated. The studied coals have trace element contents higher than the respective Clarke values for brown coals and some of them may pose environmental concerns. The elements Li, Rb, Cs, Ba, Sc, Y, La, Ce, Nd, Sm, Eu, Er, Ga, Zr, Sn, V, Nb, Ta, W, F, Cu, Zn, In, Pb, Cr, Co, Ni, and Th in the feed coals have concentrations that exceed twice the Clarke values. Most element contents in bottom ash are enriched compared with those in feed coal. Some of the volatile elements are equal or significantly depleted including Sn, Mo, Sb, F, Bi, Cd, Ge, and Pb. Fly ash has higher contents of Ga, Zr, Hf, Sn, V, Nb, Mo, and F in comparison with bottom ash. Most elements have a significant positive correlation with ash yield, indicating their inorganic association. The mixed wastes (coal slurry, bottom ash, and fly ash) in the disposal pond are slightly depleted of most of the elements studied with the exclusion of Cl, Ba, and Br. The Pernik coals and their waste products are unpromising for the extraction of REY due to their low element contents. Full article

This thorough study analyses the amounts of 43 minerals and trace elements in non-traditional wheat grains, flakes, and undigested flake portions using ICP-MS and establishes declines in their respective contents after the flake production. It also identifies appropriate dietary intakes, in vitro digestibility values, retention factors, and metal pollution indexes. The element contents in wheat flakes are lower than in wheat grains after the hydrothermal treatment process, and their declines are: Na (48–72%), Ce (47–72%), Sr (43–55%), Tl (33–43%), Ti (32–41%), U (31–44%), Ho (29–69%), Cr (26–64%), Zr (26–58%), Ag (25–52%), and Ca (25–46%). The flakes significantly contributed to the recommended dietary intake or adequate intake of particular elements for men of all categories as follows: Mn (143%) > Mo > Cu > Mg ≥ Cr > Fe (16%); for women: Mn (up to 183%) > Mo > Cu > Cr ≥ Mg > Fe (7–16%); for pregnant women aged 19–30: Mn (165%) > Mo > Cu > Mg > Cr (25%); and finally, for lactating women: Mn (127%) > Mo > Cu > Mg > Cr (17%). The contributions to the provisional tolerable weekly or monthly intakes of all toxic elements were established as being within the official limits. The daily intakes for non-essential elements were also calculated. The retention factors were calculated to assess the element concentrations in the undigested part using the digestibility values (87.4–90.5%). The highest retention factors were obtained for V (63–92%), Y (57–96%), Ce (43–76%), Pb (34–58%), Tl (32–70%), Ta (31–66%), and Ge (30–49%). K, Mg, P, Zn, Ba, Bi, Ga, Sb, Cu, Ni, and As appear to be released easily from flake matrices during digestion. The metal pollution index has been confirmed as being lower for non-traditional wheat flakes when compared with grains. Importantly, 15–25% of the metal pollution index assessed for native flakes remains in the undigested flake portion after in vitro digestion. Full article

With the global movement toward the consumption of a more sustainable diet that includes a higher proportion of plant-based foods, it is important to determine how such a change could alter the intake of cadmium and other elements, both essential and toxic. In this study, we report on the levels of a wide range of elements in foodstuffs that are both traditional and “new” to the Swedish market. The data were obtained using analytical methods providing very low detection limits and include market basket data for different food groups to provide the general levels in foods consumed in Sweden and to facilitate comparisons among traditional and “new” food items. This dataset could be used to estimate changes in nutritional intake as well as exposure associated with a change in diet. The concentrations of known toxic and essential elements are provided for all the food matrices studied. Moreover, the concentrations of less routinely analyzed elements are available in some matrices. Depending on the food variety, the dataset includes the concentrations of inorganic arsenic and up to 74 elements (Ag, Al, As, Au, B, Ba, Be, Bi, Ca, Cd, Co, Cr, Cs, Cu, Fe, Ga, Ge, Hf, Hg, K, Li, Mg, Mn, Mo, Na, Nb, Ni, P, Pb, Rb, S, Sb, Sc, Se, Si, Sn, Sr, Ta, Te, Th, Ti, Tl, U, W, V, Y, Zn, Zr, rare Earth elements (REEs) (Ce, Dy, Er, Eu, Gd, Ho, La, Lu, Nd, Pr, Sm, Tb, Tm, and Yb), platinum group elements (PGEs) (Ir, Os, Pd, Pr, Pt, Re, Rh, Ru, and Pr), and halogens (Br, Cl, and I)). The main focus (and thus the most detailed information on variation within a given food group) is on foods that are currently the largest contributors to dietary cadmium exposure in Sweden, such as pasta, rice, potato products, and different sorts of bread. Additionally, elemental concentrations in selected food varieties regarded as relatively new or “novel” to the Swedish market are provided, including teff flour, chia seeds, algae products, and gluten-free products. Full article

Geochemical baselines are crucial to explore mineral resources and monitor environmental changes. This study presents the first Laos geochemical baseline values of 69 elements. The National-scale Geochemical Mapping Project of Lao People’s Democratic Republic conducted comprehensive stream sediment sampling across Laos, yielding 2079 samples collected at 1 sample/100 km², and 69 elements were analyzed. Based on the results of LGB value, R-mode factor analysis, and scatter plot analysis, this paper analyzes the relationship between the 69 elements and the geological background, mineralization, hypergene processes and human activities in the study area. The median values of element contents related to the average crustal values were: As, B, Br, Cs, Hf, Li, N, Pb, Sb, Zr, and SiO₂, >1.3 times; Ba, Be, Cl, Co, Cr, Cu, F, Ga, Mn, Mo, Ni, S, Sc, Sr, Ti, Tl, V, Zn, Eu, Al₂O₃, Tot.Fe₂O_3, MgO, CaO, and Na₂O, <0.7 times; and Ag, Au, Bi, Cd, Ge, Hg, I, In, Nb, P, Rb, Se, Sn, Ta, Th, U, W, Y, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and K₂O, 0.7–1.3 times. R-mode factor analysis based on principal component analysis and varimax rotation showed that they fall into 12 factors related to bedrock, (rare earth, ferrum-group, and major Al₂O₃ and K₂O elements; mineralization–Au, Sb, and As) and farming activities–N, Br, S, and C). This study provides basic geochemical data for many fields, including basic geology, mineral exploration, environmental protection and agricultural production in Laos. Full article

The moss biomonitoring technique was used for assessment of air pollution in the central part of Georgia, Caucasus, in the framework of the UNECE ICP Vegetation. A total of 35 major and trace elements were determined by two complementary analytical techniques, epithermal neutron activation analysis (Na, Mg, Al, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, Se, B, Rb, Sr, Zr, Mo, Sb, I, Cs, Ba, La, Ce, Nd, Sm, Eu, Tb, Yb, Hf, Ta, W, Th, and U) and atomic absorption spectrometry (Cu, Cd, and Pb) in the moss samples collected in 2019. Principal Component Analyses was applied to show the association between the elements in the study area. Four factors were determined, of which two are of geogenic origin (Factor 1 including Na, Al, Sc, Ti, V, Cr, Fe, Co, Ni, Th, and U and Factor 3 with As, Sb, and W), mixed geogenic–anthropogenic (Factor 2 with Cl, K, Zn, Se, Br, I, and Cu) and anthropogenic (Factor 4 comprising Ca, Cd, Pb, and Br). Geographic information system (GIS) technologies were used to construct distributions maps of factor scores over the investigated territory. Comparison of the median values with the analogous data of moss biomonitoring in countries with similar climatic conditions was carried out. Full article

Sb-containing catalysts (SbZrO_x (SbZr), SbCeO_x (SbCe), SbCeZrO_x (SbCeZr)) were prepared by citric acid method and investigated for the selective catalytic reduction (SCR) of NO_x with NH₃ (NH₃-SCR). SbCeZr outperformed SbZr and SbCe and exhibited the highest activity with 80% NO conversion in the temperature window of 202–422 °C. Meanwhile, it also had good thermal stability and resistance against H₂O and SO₂. Various characterization methods, such as XRD, XPS, H₂-TPR, NH₃-TPD, and in situ diffuse reflectance infrared Fourier transform (DRIFT), were applied to understand their different behavior in NO_x removal. The presence of Sb in the metal oxides led to the difference in acid distribution and redox property, which closely related with the NH₃ adsorption and NO oxidation. Brønsted acid and Lewis acid were evenly distributed on SbCe, while Brønsted acid dominated on SbCeZr. Compared with Brønsted acid, Lewis acid was slightly active in NH₃-SCR. The competition between NH₃ adsorption and NO oxidation was dependent on SbO_x and metal oxides, which were found on SbCe while not on SbCeZr. Full article

The correct assessment of the presence of potentially contaminating elements in soil, as well as in fruits cultivated and harvested from the same places has major importance for both the environment and human health. To address this task, in the case of the Republic of Moldova where the fruit production has a significant contribution to the gross domestic product, the mass fractions of 37 elements (Na, Mg, Al, Ca, Si, K, Mn, Fe, Sc, Ti, V, Cr, Co, Ni, Zn, As, Br, Rb, Sr, Zr, Mo, Cd, Sb, Cs, Ba, La, Ce, Nd, Sm, Eu, Tb, Yb, Hf, Ta, W, Th, and U) were determined by instrumental neutron activation analysis in soil collected from four Moldavian orchards. In the case of three types of fruits, grapes, apples, and plums, all of them collected from the same places, only 22 elements (Na, Mg, Cl, K, Ca, Sc, Mn, Fe, Co, Ni, Cu, Zn, As, Br, Rb, Sr, Sb, Cs, Ba, La, Th, and U) were detected. The enrichment factor, contamination factor, geo-accumulation index, as well as pollution load index were calculated to assess the soil contamination. At the same time, the metal uptake from the soil into fruits was estimated by means of transfer factors. Soil samples showed for almost all elements mass fractions closer to the upper continental crust with the exception of a slightly increased content of As, Br, and Sb, but without overpassing the officially defined alarm thresholds. In the case of fruits, the hazard quotients for all elements with the exception of Sb in fruits collected in two orchards were below unity. A subsequent discriminant analysis allowed grouping all fruits according to their type and provenance. Full article

To get more data on the geochemistry of Black Sea euxinic sediments, a 50-cm core was collected at a depth of 600 m on a Western Black Sea Continental Platform slope. The core contained unconsolidated sediments rich in cocoolithic ooze and mud. Epithermal Neutron and Prompt Gamma Activation Analysis were used to determine the content of nine major (Na, Mg, Al, Si, K, Ca, Ti, Mn, and Fe as oxides) and 32 trace elements (Cl, Sc, V, Cr, Co, Ni, Zn, As, Se, Br, Rb, Sr, Zr, Mo, Sn, Sb, Cs, Ba, La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Yb, Hf, Ta, W, Th, and U) with a precision varying between 3 and 9%. The core contained unconsolidated sediment rich in coccolithic ooze and mud. Previous ${}^{210}$ Pb geochronology suggests an age of ∼1 ky of considered sediments. Major components distribution showed that, except for Cl and Ca, the contents of all other elements are similar to Upper Continental Crust (UCC) and North American Shale Composite (NASC). The distribution of the 32 trace elements showed similarities to the UCC, except for redox-sensitive metals Fe, Se, Mo, and U, of which the significantly higher content reflects the presence of euxinic conditions during deposition. A chondrite normalized plot of nine rare earth elements indicated a similarity to UCC and NASC, suggesting a continental origin of sedimentary material. Full article

Crystalline ceramics are intensively investigated as effective materials in various nuclear energy applications, such as inert matrix and accident tolerant fuels and nuclear waste immobilization. This paper presents an analysis of the current status of work in this field of material sciences. We have considered inorganic materials characterized by different structures, including simple oxides with fluorite structure, complex oxides (pyrochlore, murataite, zirconolite, perovskite, hollandite, garnet, crichtonite, freudenbergite, and P-pollucite), simple silicates (zircon/thorite/coffinite, titanite (sphen), britholite), framework silicates (zeolite, pollucite, nepheline /leucite, sodalite, cancrinite, micas structures), phosphates (monazite, xenotime, apatite, kosnarite (NZP), langbeinite, thorium phosphate diphosphate, struvite, meta-ankoleite), and aluminates with a magnetoplumbite structure. These materials can contain in their composition various cations in different combinations and ratios: Li–Cs, Tl, Ag, Be–Ba, Pb, Mn, Co, Ni, Cu, Cd, B, Al, Fe, Ga, Sc, Cr, V, Sb, Nb, Ta, La, Ce, rare-earth elements (REEs), Si, Ti, Zr, Hf, Sn, Bi, Nb, Th, U, Np, Pu, Am and Cm. They can be prepared in the form of powders, including nano-powders, as well as in form of monolith (bulk) ceramics. To produce ceramics, cold pressing and sintering (frittage), hot pressing, hot isostatic pressing and spark plasma sintering (SPS) can be used. The SPS method is now considered as one of most promising in applications with actual radioactive substances, enabling a densification of up to 98–99.9% to be achieved in a few minutes. Characteristics of the structures obtained (e.g., syngony, unit cell parameters, drawings) are described based upon an analysis of 462 publications. Full article

Mediterranean Temporary Ponds (MTPs) constitute priority habitat under the European Union Habitats’ Directive. They are inhabited by rare species and subjected to unstable environmental conditions. Lakes and ponds act as early indicators of climate change, to which high altitude ecosystems are especially vulnerable. This study presents a full dataset of the geo-environmental parameters of such habitats (MTPs) along with their current ecological status for the first time. Furthermore, this paper aims to address the lack of basic geo-environmental background on the network of MTPs of Mt. Oiti concerning their geological, geomorphological, mineralogical and geochemical characteristics along with the pressures received from various activities. The study area is located in a mountainous Natura 2000 site of Central Greece, which hosts four MTPs. Fieldwork and sampling of water and bottom sediments were carried out during dry and wet periods between 2012 and 2014. Electrical Resistivity Tomography measurements identified synforms shaped under the ponds that topography does not always adopt them, mostly due to erosion procedures. The most significant feature, distinguishing those pond waters from any other province water bodies is the extremely low content of all studied ions (including NO₂⁻, NO₃⁻, NH₄⁺, PO₄³⁻, HCO₃⁻, SO₄²⁻, Al, As, B, Ba, Ca, Cd, Ce, Cl, Co, Cr, Cs, Cu, Fe, Ga, Gd, Ge, Hf, Hg, K, La, Li, Mg, Mn, Mo, Na, Ni, P, Rb, S, Sb, Se, Si, Sn, Sr, Ti, U, V, W, Zn, and Zr). MTPs water bodies are of bicarbonate dominant type, and a fresh meteoric water origin is suggested. The main pressures identified were grazing and trampling by vehicles. MTPs of Mt. Oiti were classified according to their ecological status form excellent to medium. Our results can contribute to a better understanding of the mountainous temporary ponds development in the Mediterranean environment. Full article

This paper discusses the content, distribution, modes of occurrence, and enrichment mechanism of mineral matter and trace elements of an Early Permian coal from Songshao (Yunnan Province, China) by means of coal-petrological, mineralogical, and geochemical techniques. The results show that the Songshao coal is characterized by high total and organic sulfur contents (3.61% and 3.87%, respectively). Lithium (170.39 μg/g) and Zr (184.55 μg/g) are significantly enriched in the Songshao coal, and, to a lesser extent, elements such as Hg, La, Ce, Nd, Th, Sr, Nb, Sn, Hf, V, and Cr are also enriched. In addition to Hg and Se that are enriched in the roof and floor strata of the coal seam, Li, La, Ce, Pr, Nd, Sm, Gd, Y, Cd, and Sb are slightly enriched in these host rocks. Compared to the upper continental crust, rare earth elements and yttrium in the host rocks and coal samples are characterized by a light-REE enrichment type and have negative Eu, positive Ce and Gd anomalies. Major minerals in the samples of coal, roof, and floor are boehmite, clay minerals (kaolinite, illite, and mixed layer illite-smectite), pyrite, and anatase. Geochemical and mineralogical anomalies of the Songshao coal are attributed to hydrothermal fluids, seawater, and sediment-source rocks. Full article

A selective separation and recycling system for metal ions was developed by homogeneous liquid-liquid extraction (HoLLE) using a fluorosurfactant. Sixty-two different elemental ions (e.g., Ag, Al, As, Au, B, Ba, Be, Bi, Ca, Cd, Ce, Co, Cr, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Hg, Ho, In, Ir, La, Lu, Mg, Mn, Mo, Nb, Nd, Ni, Os, P, Pb, Pd, Pr, Pt, Re, Rh, Ru, Sb, Sc, Se, Si, Sm, Sn, Sr, Ta, Tb, Te, Ti, Tl, Tm, V, W, Y, Yb, Zn, and Zr) were examined. By changing pH from a neutral or alkaline solution (pH ≥ 6.5) to that of an acidic solution (pH < 4.0), gallium, zirconium, palladium, silver, platinum, and rare earth elements were extracted at >90% efficiency into a sedimented Zonyl FSA^® (CF₃(CF₂)_n(CH₂)₂S(CH₂)₂COOH, n = 6–8) liquid phase. Moreover, all rare earth elements were obtained with superior extraction and stripping percentages. In the recycling of rare earth elements, the sedimented phase was maintained using a filter along with a mixed solution of THF and 1 M sodium hydroxide aqueous solution. The Zonyl FSA^® was filtrated and the rare earth elements were recovered on the filter as a hydroxide. Furthermore, the filtrated Zonyl FSA was reusable by conditioning the subject pH. Full article