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1.
Methods Mol Biol ; 2566: 53-62, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36152242

RESUMO

Adipocytes and osteoblasts derive from a common mesenchymal progenitor present in a range of connective tissues. Differentiation of the progenitors toward the two cell lineages can be induced in vitro through well-established protocols, and leads to the appearance of lipid-laden adipocytes and osteoblasts embedded in a mineralized matrix. The formation of these two lineages in cell cultures can be monitored using lipophilic dyes such as Oil Red O and substances binding to mineral deposits such as Alizarin Red S, respectively. However, these common staining techniques require cell fixation and are thus incompatible with live analyses. Recently, alternative approaches using vital stains have allowed the dual visualization and fluorescence imaging of adipogenic and osteogenic lineages in live cultures. Here we present the concomitant analysis of cultures containing adipogenic and osteogenic cell types using live staining, combining LipidTox Red and tetracycline with NucRed nuclear counterstain for confocal imaging. This approach can be applied to visualize the kinetics and 3D structure of differentiating mesenchymal cultures over time and highlights the interaction of adipose and mineralized compartments associated with bone marrow stroma.


Assuntos
Células-Tronco Mesenquimais , Adipogenia , Diferenciação Celular , Células Cultivadas , Corantes/metabolismo , Lipídeos , Minerais , Osteogênese , Células-Tronco , Tetraciclinas/metabolismo
2.
J Hazard Mater ; 441: 129883, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36108495

RESUMO

Cadmium (Cd) and lead (Pb) are two of the most common elements found in contaminated sites. The behavior of specific metals in the soil may be affected by other metals because of the competition for adsorption sites. In this study, adsorption experiments after chemical extraction, multi-surface models, and advanced spectroscopy technology were jointly used to explain the adsorption mechanism of Cd and Pb and to determine the contribution of each component in the competitive system. The results show that pH is the key factor in determining the contribution of soil components to metal adsorption. Soil organic matter (SOM) is the dominant adsorbent for both Cd and Pb. Clay minerals play an adsorption role at low pH, whereas Fe/Al oxides adsorb metals primarily in the high pH range. Further, the competitive effect of Pb on Cd occurred primarily on SOM rather than on clay minerals. When the Pb concentration increased from 0 to 500 mg/L, the adsorption of Cd on SOM decreased by 132.0 mg/kg, whereas it decreased only by 1.9 mg/kg on clay minerals. Therefore, the competitive effect of Pb on Cd cannot be ignored in soils with high organic matter content.


Assuntos
Metais Pesados , Poluentes do Solo , Adsorção , Cádmio/química , Argila , Chumbo/análise , Metais Pesados/análise , Minerais , Óxidos/análise , Solo/química , Poluentes do Solo/análise
3.
J Environ Sci (China) ; 124: 688-698, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36182174

RESUMO

It has been documented that organic contaminants can be degraded by hydroxyl radicals (•OH) produced by the activation of H2O2 by Fe(II)-bearing clay. However, the interfacial electron transfer reactions between structural Fe(II) and H2O2 for •OH generation and its effects on contaminant remediation are unclear. In this study, we first investigated the relation between •OH generation sites and sulfamethoxazole (SMX) degradation by activating H2O2 using nontronite with different reduction extents. SMX (5.2-16.9 µmol/L) degradation first increased and then decreased with an increase in the reduction extent of nontronite from 22% to 62%, while the •OH production increased continually. Passivization treatment of edge sites and structural variation results revealed that interfacial electron transfer reactions between Fe(II) and H2O2 occur at both the edge and basal plane. The enhancement on basal plane interfacial electron transfer reactions in a high reduction extent rNAu-2 leads to the enhancement on utilization efficiencies of structural Fe(II) and H2O2 for •OH generation. However, the •OH produced at the basal planes is less efficient in oxidizing SMX than that of at edge sites. Oxidation of SMX could be sustainable in the H2O2/rNAu-2 system through chemically reduction. The results of this study show the importance role of •OH generation sites on antibiotic degradation and provide guidance and potential strategies for antibiotic degradation by Fe(II)-bearing clay minerals in H2O2-based treatments.


Assuntos
Peróxido de Hidrogênio , Sulfametoxazol , Antibacterianos , Argila , Elétrons , Compostos Ferrosos , Minerais/química , Oxirredução , Sulfametoxazol/química
4.
J Environ Sci (China) ; 124: 915-922, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36182194

RESUMO

As a biosorbent, algae are frequently used for the biotreatment or bioremediation of water contaminated by heavy metal or radionuclides. However, it is unclear that whether or not the biomineralization of these metal or radionuclides can be induced by algae in the process of bioremediation and what the mechanism is. In this work, Ankistrodsemus sp. has been used to treat the uranium-contaminated water, and more than 98% of uranium in the solution can be removed by the alga, when the initial uranium concentration ranges from 10 to 80 mg/L. Especially, an unusual phenomenon of algae-induced uranium biomineralization has been found in the process of uranium bioremediation and its mineralization mechanism has been explored by multiple approaches. It is worth noticing that the biomineralization of uranium induced by Ankistrodsemus sp. is significantly affected by contact time and pH. Uranium is captured rapidly on the cell surface via complexation with the carboxylate radical, amino and amide groups of the microalgae cells, which provides nucleation sites for the precipitation of insoluble minerals. Uranium stimulates Ankistrodsemus sp. to metabolize potassium ions (K+), which may endow algae with the ability to biomineralize uranium into the rose-like compreignacite (K2[(UO2)6O4(OH)6]•8H2O). As the time increased, the amorphous gradually converted into compreignacite crystals and a large number of crystals would expand over both inside and outside the cells. To the best of our knowledge, this is the first investigated microalgae with a time-dependent uranium biomineralization ability and superior tolerance to uranium. This work validates that Ankistrodsemus sp. is a promising alga for the treatment of uranium-contaminated wastewater.


Assuntos
Clorófitas , Urânio , Amidas , Biomineralização , Minerais/química , Potássio , Radioisótopos , Urânio/química , Compostos de Urânio , Águas Residuárias , Água
5.
Chemosphere ; 310: 136799, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36228728

RESUMO

The iron mineral-catalyzed degradation of cephalosporin antibiotics with H2O2 occurs ubiquitously in nature. Despite numerous studies, the effects of environmental conditions on reactive species production and degradation processes of cephalosporins remain unclear. Here, we report the iron mineral of goethite as the efficient and heterogenous catalyst for the degradation of cefradine (CRD) via H2O2 activation under different conditions involving pH and visible light irradiation. Results show that the CRD removal rate is highly dependent on pH and visible light irradiation. Interestingly, when the pH ranges from 4.0 to 7.0, the degradation intermediates of CRD under dark are the same as under visible light conditions in the goethite/H2O2 system. And, the ratio of CRD degradation rate constant (kLight/kDark) reaches a maximum at pH 5.0, suggesting that CRD existing as zwitterion species is preferable for its removal with photoassistance. The mechanism investigation reveals that both •OH and ≡[FeIVO]2+ oxidants are generated during the reaction process, and •OH is the major oxidant at acidic pH, while ≡[FeIVO]2+ is more likely to be formed with photoassistance at near-neutral pH. According to UPLC-MS/MS analysis, CRD degradation likely happens via hydrogen atom abstraction from cyclohexadienyl by •OH, thioether and olefin oxidation by ≡[FeIVO]2+, and FeIII-catalyzed hydrolytic cleavage of ß-lactam ring. These findings highlight the vital roles of pH and photoassistance in the heterogeneously activated H2O2 with goethite for CRD degradation.


Assuntos
Cefradina , Peróxido de Hidrogênio , Compostos Férricos , Cromatografia Líquida , Espectrometria de Massas em Tandem , Minerais , Ferro , Oxirredução , Oxidantes , Luz , Concentração de Íons de Hidrogênio
6.
Chemosphere ; 310: 136873, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36252896

RESUMO

To address climate change concerns, and reduce the carbon footprint caused by fossil fuel use, it is likely that blend ratios of renewable biodiesel with commercial mineral diesel fuel will steadily increase, resulting in biodiesel use becoming more widespread. Exhaust toxicity of unblended biodiesels changes depending on feedstock type, however the effect of feedstock on blended fuels is less well known. The aim of this study was to assess the impact of biodiesel feedstock on exhaust toxicity of 20% blended biodiesel fuels (B20). Primary human airway epithelial cells were exposed to exhaust diluted 1/15 with air from an engine running on conventional ultra-low sulfur diesel (ULSD) or 20% blends of soy, canola, waste cooking oil (WCO), tallow, palm or cottonseed biodiesel in diesel. Physico-chemical exhaust properties were compared between fuels and the post-exposure effect of exhaust on cellular viability and media release was assessed 24 h later. Exhaust properties changed significantly between all fuels with cottonseed B20 being the most different to both ULSD and its respective unblended biodiesel. Exposure to palm B20 resulted in significantly decreased cellular viability (96.3 ± 1.7%; p < 0.01) whereas exposure to soy B20 generated the greatest number of changes in mediator release (including IL-6, IL-8 and TNF-α, p < 0.05) when compared to air exposed controls, with palm B20 and tallow B20 closely following. In contrast, canola B20 and WCO B20 were the least toxic with only mediators G-CSF and TNF-α being significantly increased. Therefore, exposure to palm B20, soy B20 and tallow B20 were found to be the most toxic and exposure to canola B20 and WCO B20 the least. The top three most toxic and the bottom three least toxic B20 fuels are consistent with their unblended counterparts, suggesting that feedstock type greatly impacts exhaust toxicity, even when biodiesel only comprises 20% of the fuel.


Assuntos
Biocombustíveis , Material Particulado , Humanos , Biocombustíveis/toxicidade , Biocombustíveis/análise , Material Particulado/análise , Fator de Necrose Tumoral alfa , Óleo de Sementes de Algodão , Emissões de Veículos/toxicidade , Emissões de Veículos/análise , Gasolina/toxicidade , Minerais
7.
Food Chem ; 403: 134315, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36183466

RESUMO

Sixteen multiparous Holstein cows in four blocks of 4 × 4 Latin square over 4-week experimental periods were used to study the effects of seaweed (Saccharina latissima) supplement (with/without) and protein source (rapeseed meal (RSM)/wheat distiller's grain (WDG)) on milk mineral concentrations. Dietary treatments did not affect milk production and basic composition. Feeding seaweed slightly decreased milk Ca and Cu concentrations; whilst increased (by 3.3-fold) milk iodine (I) concentration, due to a higher dietary I supply. Substitution of WDG with RSM increased feed-to-milk transfer of Ca, Na, and Se and decreased that of Mg, P, Fe, and Mn; but only reduced milk Mn and I concentrations (the latter by 27 % as a potential result of increased glucosinolate intake). Seaweed supplement can improve milk I content when cows' I supply/availability is limited, but care should be taken to avoid excess milk I contents that may pose nutritional risks for young children.


Assuntos
Brassica napus , Brassica rapa , Feófitas , Alga Marinha , Feminino , Bovinos , Animais , Leite/metabolismo , Lactação , Ração Animal/análise , Dieta/veterinária , Suplementos Nutricionais , Grão Comestível , Verduras , Minerais/metabolismo
8.
J Environ Manage ; 325(Pt A): 116473, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36228398

RESUMO

The adsorptive fractionation of humic acid (HA) at the interface between minerals and water can significantly affect the fate of pollutants in water-soil environment. However, the adsorptive fractionation behavior of HA on kaolinite and its effect on the migration of fluoroquinolones (FQs) have not been fully understood. In this study, fluorescence and infrared spectroscopy, combined with two-dimensional correlation analyses, were used to explore the adsorptive fractionation of humic acid (HA) and its effects on ofloxacin adsorption on kaolinite. The results indicated that humic-like, rather than reduced quinone-like and tyrosine-like, was the main adsorptive fractionation component and preferentially bound to the Al-O sites of kaolinite. The adsorption mechanisms of humic-like and tyrosine-like mainly include hydrogen bonds between acidic functional groups and the Si-O or Al-O groups of kaolinite, n-π electron donor-acceptor interaction and electrostatic attraction. At pH 7.0, with addition of 4.0 and 16.0 mg C/L HA in solution, the adsorptive fractionation of HA on kaolinite led to increases in ofloxacin (in zwitterionic form) adsorption capacity by 1.46 and 3.35 mg/g, respectively. The interactions between ofloxacin and the humic-like were mainly hydrogen bonds and electrostatic attraction. Therefore, the influence of adsorptive fractionation of dissolved organic matter on minerals should be considered in estimating FQs environmental behaviors.


Assuntos
Substâncias Húmicas , Caulim , Substâncias Húmicas/análise , Caulim/química , Adsorção , Ofloxacino , Minerais/química , Fluoroquinolonas , Sítios de Ligação , Água , Tirosina
9.
Chemosphere ; 311(Pt 1): 136972, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36283427

RESUMO

Heterogeneous Fenton-like systems were exploited for the degradation of Reactive Red X-3B (RR X-3B) using iron-carbon composite, sponge iron, chalcopyrite and pyrite as catalysts. The effect of operational variables on the catalytic activity and metal leaching behavior of catalysts was evaluated and the catalytic mechanism was discussed. The experimental results showed that under the optimum conditions, chemical oxygen demand (COD) removals by Fenton-like systems could reach 89.91%, 86.84%, 80.11% and 60.02% with iron-carbon composite, sponge iron, chalcopyrite and pyrite, respectively. Micro-electrolysis of iron-carbon composite and sponge iron resulted in higher COD removal at acid pH range. Electron Paramagnetic Resonance (EPR) analysis and quenching tests showed that •OH was the main reactive oxygen species responsible for the degradation of RR X-3B. A large amount of Fe2+ leached from iron-carbon composite and sponge iron, which served as a homogeneous Fenton catalyst during the degradation of RR X-3B. In contrast, much lower amount of Fe2+ was leached from chalcopyrite and pyrite, and surface catalysis of the minerals played more important role in the generation of •OH. Surface characterization and density functional theory (DFT) calculation results illustrated that ≡Fe(II) was the primary surface catalytic site during the reaction. The reduction of ≡Fe(III) and ≡Cu(II) can be facilitated by sulfides on the mineral surface. The Fenton-like systems catalyzed by iron-based materials exhibited higher H2O2 utilization and COD removal than classical Fenton system. With the lower metal leaching concentration and stable surface property, chalcopyrite and pyrite may be more practical applicable from a long-term catalytic activity point of view.


Assuntos
Compostos Férricos , Peróxido de Hidrogênio , Peróxido de Hidrogênio/química , Compostos Férricos/química , Ferro/química , Catálise , Oxirredução , Minerais/química , Metais , Carbono/química
10.
J Environ Manage ; 325(Pt B): 116605, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36347187

RESUMO

Fertilization changes the soil organic carbon (SOC) composition, affecting the carbon cycle of paddy soil. Understanding the mechanisms of physical fraction and chemical composition of SOC responding to fertilization can help regulate the nutrient release and carbon sequestration. However, it is unclear whether these changes in SOC composition to fertilization are consistent and how these are regulated by biotic and abiotic properties. Therefore, a positioning experiment in a rice field was conducted with a total of nine treatments. Chemical fertilizers (0, 337.5, and 675 kg ha-1; C0, C50, and C100, respectively) and fungal residue (0, 10,000, and 20,000 kg ha-1; F0, F50, and F100, respectively) were applied to evaluated (i) changes in the physical fraction and chemical composition of SOC, (ii) changes in soil properties, microbial biomass and community, and (iii) establish relationships among soil properties, microbial community, microbial biomass, and SOC composition. Our results showed that the application of fungal residue exhibited more significant effects on SOC physical fractions than those with the chemical fertilizers. Furthermore, the chemical composition of SOC was more respond to the application of chemical fertilizers than fungal residue. The partial least squares path model indicated that soil properties mainly affected the mineral-associated organic carbon (MAOC) by microbial biomass. In addition, bacterial diversity played an important role in improving the accumulation of MAOC. The SOC chemical composition was mediated by fungal community composition and bacterial diversity. In conclusion, fungal residue application affected SOC physical fraction by increasing soil properties, microbial biomass, and bacterial diversity. Chemical fertilizers application mainly mediated the chemical composition of SOC by altering fungal community composition and decreasing bacterial diversity.


Assuntos
Oryza , Solo , Solo/química , Carbono/química , Fertilizantes/análise , Agricultura/métodos , Microbiologia do Solo , Oryza/química , Minerais , Fertilização
11.
Sci Total Environ ; 856(Pt 1): 158840, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36122729

RESUMO

The sea spray effect can severely influence the isotopic signature of terrestrial individuals in coastal regions. To further specify this effect, beach grass was grown in a greenhouse under controlled environmental conditions and sprayed with mineral salt solution containing different mineral salts but only traces of NaCl (group 1). Another group of plants was sprayed with salty water from the Schlei inlet and the Baltic Sea, respectively (group 2). Control plants were only sprayed with tap water. Isotope analyses were conducted on the unwashed and washed plants (δ13Ccellulose, δ18Ocellulose, δ34Stotal S, 87Sr/86Sr), soil (δ18Osulfate, δ34Ssulfate, 87Sr/86Sr), and spray as well as irrigation water (δ18Osulfate, δ34Ssulfate, 87Sr/86Sr). Moreover, elemental analyses were performed on the water samples. The sea spray effect was visible in all isotopic systems under study. The uptake of SO42-, HCO3-, and Sr2+ directly affected plants of group 1, while plants of group 2, sprayed with salty water, additionally showed salinity stress in the case of α-cellulose and total sulfur due to biochemical reactions of the plants. Very high concentrations in HCO3- or SO42- also affected the plants' isotopic signatures. The impact of the sea spray and additional stress reactions were quantified. Our study is the first experiment creating an artificial sea spray effect in a greenhouse. This experiment for the first time enables the identification and quantification of the sea spray effect in environmental samples. The marine signature taken up by the plants and recorded by the investigated isotopic systems is apparently high and should have an impact on the isotopic fingerprints of animal consumers at the coast, as evidenced for archaeological animals from the Viking Haithabu and the early medieval Schleswig sites located close to the Baltic Sea. This result demonstrates the potential of greenhouse experiments as an isotopic predictor of the past local sea spray effect.


Assuntos
Poaceae , Enxofre , Animais , Água , Celulose , Sulfatos , Minerais
12.
Sci Total Environ ; 856(Pt 1): 158969, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36162584

RESUMO

A review of the localities in continental rocks where H2-rich gases have been reported, showed that they are mainly located near orogenic gold deposits. Two types of geomorphological features known as markers of gas venting in sedimentary basins were also systematically observed near orogenic gold deposits on satellite images. They consist in both barren ground depressions and high densities of small (<20 m in diameter) circular- and comet-shaped white spots in 32 and 7 localities, respectively. Point pattern analysis revealed that the white spots are self-organized, and similar to previously described vegetation patterns associated with termite mounds and fairy circles. We proposed a geochemical model to account for this relationship between orogenic gold deposits, H2 emanations and geomorphological features. Fe­carbonates are ubiquitous mineral products associated with gold mineralization. They can further dissolve in the presence of aqueous fluid due to their high reactivity below 200 °C to produce magnetite and up to ∼1 mol H2 per kg of rock along with ∼3 mol/kg CO2. This process induces a solid volume decrease of 50 %. Therefore, we propose that Fe­carbonate dissolution is (1) the primary source of H2 in orogenic gold deposit areas, and (2) involved in the formation of the geomorphological structures reported here, providing a new framework to understand their seemingly complex formation. Ground depressions and white spots are possible tools for gold exploration. Actually, we identified four new areas where we suspect possible orogenic gold deposits. The association between H2-rich gas and ground depressions was also made near other formations containing Fe­carbonates such as iron formations and carbonatites. This suggests that H2 production through Fe­carbonate dissolution is not restricted to gold deposits. The global H2 production in crustal rocks associated with Fe­carbonate alteration is estimated to 3 × 105 mol/yr.


Assuntos
Depressão , Ouro , Minerais/química , Gases , Carbonatos
13.
Sci Total Environ ; 856(Pt 1): 159034, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36167127

RESUMO

Biochar when applied into soil, together with soil clay minerals, may provide habitats for soil microbes and shift soil microbial community structure. Although several mechanisms have been proposed to explain the effects of biochar on microbial community, the impact of biochar on quorum sensing (QS) and QS-regulated behavior is poorly understood. In this study, we compared the effects of biochar and three common soil minerals (i.e., montmorillonite, kaolinite, and goethite) on QS and biofilm formation. Pseudomonas aeruginosa PAO1 with complete QS systems was selected as a model organism. Our results showed that biochar and goethite effectively promoted microbial QS and biofilm formation, while montmorillonite and kaolinite posed no significant effect. Live/Dead staining, SEM and density-dependent QS activity indicated that biochar was beneficial to cell viability maintenance and cell aggregations, which improved the efficiency of intercellular communications through QS. QS mutant strain experiments confirmed that biochar enhanced PAO1 biofilm formation by promoting QS. Goethite promoted biofilm formation with a different mechanism that cell debris induced by iron ions and positive charge on goethite surface provided raw materials for bacterial biofilm formation. Our findings provide evidence that the presence of biochar can enhance QS and biofilm formation through a feedforward loop of the QS system. This contributes to better understand biochar-mediated microbial cell to cell communications through QS.


Assuntos
Pseudomonas aeruginosa , Percepção de Quorum , Bentonita , Caulim , Biofilmes , Minerais , Solo
14.
Sci Total Environ ; 856(Pt 1): 159025, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36167136

RESUMO

Investigators are debating on the positive and negative priming effects of biochar on native soil organic carbon (SOC), which is largely attributed to the technical barrier of identifying biochar contribution to the apparently measured SOC or mineralized CO2. We combined benzene polycarboxylic acids (BPCAs) molecular biomarkers and soil particle density fractionation to identify biochar contributions to the carbon content in three representative allitic soils in Yunnan. The soil-biochar mixture was incubated for one-month to avoid significant biodegradation of biochar. The results showed that BPCAs were mainly distributed in free light fractions (fLF) up to 87 % of the total BPCAs contents after one month incubation. Recognition of BPCAs in occluded light fractions (oLF) and heavy fractions (HF) suggested a significant interaction between biochar and soil mineral particles. In addition, the percentage of B6CA is comparable or even higher in HF than in fLF or oLF. Thus, biochar-mineral interactions may be an additional stabilization mechanism besides the condensed aromatic structures in biochar. The apparently measured carbon contents increased after biochar application, and both positive and negative priming effects to native SOC were observed after deducting biochar contents based an accurate calculation from BPCAs. The most native SOC depletion (positive priming effects) was noted for the soil with the most favored biochar embedding in soil mineral compositions. This study emphasized that combining BPCAs molecular biomarkers and soil particle density fractionation could accurately quantify different carbon pools, and thus facilitate a comprehensive understanding on the stabilization and turnover of biochar in soils.


Assuntos
Benzeno , Solo , Solo/química , Benzeno/análise , Carbono/análise , China , Carvão Vegetal/química , Minerais , Ácidos Carboxílicos , Biomarcadores
15.
Sci Total Environ ; 856(Pt 1): 159078, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36179848

RESUMO

The acidophilic sulfur oxidizing bacterium (SOB), Acidithiobacillus ferrooxidans, has been found to stimulate elemental sulfur (S0) oxidation and mineral weathering in alkaline Fe ore tailings. However, A. ferrooxidans growth and activities depend on the pH conditions surrounding their interfaces with minerals. The present study aimed to investigate how pH influences bacterial growth and functions in Fe ore tailings. A simulated aquatic 'homogeneous' incubation system was initially adjusted into acidic (pH 4), neutral (pH 7) and alkaline (pH 9) conditions, which mimicked the microenvironmental conditions of the water-cell-mineral interfaces in the tailings. It was found that A. ferrooxidans grew well and oxidised S0 under the prevailing and initially acidic conditions (pH < 6). These stimulated the weathering of biotite and amphibole-like minerals and the formation of nanosized jarosite and ferrihydrite-like minerals mediated by extracellular polymer substrate (EPS). In contrast, the initially neutral/alkaline pH conditions (i.e., pH > 7) with the presence of the alkaline tailings restricted SOB growth and functions in S0-oxidation and mineral weathering. These findings suggest that it is essential to prime acidic conditions in microenvironments to support SOB growth, activities, and functions toward mineral weathering in tailings, providing critical basis for involving SOB in eco-engineered pedogenesis in tailings.


Assuntos
Minerais , Enxofre , Bactérias , Oxirredução , Ferro , Concentração de Íons de Hidrogênio
16.
Sci Total Environ ; 856(Pt 1): 159123, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36181795

RESUMO

The enrichment of rare, scattered, rare earth, and noble elements, such as Li, Ga, Ge, rare earth elements and yttrium (REY), platinum group elements (PGE), Au, and Ag, have been discovered in the Late Permian coals from southwestern China. With the gradual depletion of traditional ore deposits, the geochemistry and resource utilization of critical metals in coals have received considerable attention. The geochemistry of associated elements in the Late Permian coals from the No. 10 coal profile of the Yueliangtian (YLT) underground mine, Liupanshui coalfield in Guizhou, were investigated to reveal the sediment source of inorganic components, as well as utilization prospects and controlling factors of critical metals. Silver and Pb were slightly enriched in the Yueliangtian coals, while Be, Rb, Sr, Mo, Cs, Ba, Tl, Bi, and U were significantly lower than that of world hard coals. The concentrations of total REY and individual elements in the Yueliangtian coals were similar to those of world hard coals. The minerals kaolinite, pyrite, calcite, and quartz predominated in coals, with trace amounts of anatase, gypsum, and apatite. High anatase proportion was identified in the floor and roof rock samples. Based on the Al2O3/TiO2 and Zr/TiO2 versus Nb/Y ratios, elemental assemblages, REY distribution, and paleogeography, the sediment source of mineral matter in the Yueliangtian coals dominated by felsic-intermediate rocks that from a distal volcanic arc or orogens was inferred. The terrigenous debris in the roof and floor rocks primarily originated from the high-Ti basalt of the Emeishan Large Igneous Province (ELIP). The relatively low elemental concentrations in these coals were primarily determined by their sediment sources. Although most critical metals in this coal were not enriched, the concentration of REY in coal ash was high enough to be considered as a potential resource for REY recovery given the extremely low ash yields of this coal.


Assuntos
Minas de Carvão , Metais Terras Raras , Carvão Mineral/análise , Metais , Cinza de Carvão , Minerais
17.
Sci Total Environ ; 857(Pt 2): 159372, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36244493

RESUMO

Mercapto-modified palygorskite (MP) is an efficient novel amendment with superior ability to decrease soil Cd bioavailability, but the unclear immobilization mechanism has become the bottleneck of its performance improvement and precise application. In order to clarify the Cd reducing mechanism of MP, long-term and short-term soil incubation with three types of soils (paddy soil, alluvial soil and yellow mountain soil) and sorption verification experiments were conducted to investigate the dynamic process of soil labile Cd impacted by MP and the synergetic effects on labile Fe, Mn, S and dissolved organic carbon via in-situ diffusive gradients in thin-films and soil solution sampling techniques. MP with four dosages rapidly and continuously decreased soil labile Cd contents by 14.50 % ∼ 89.16 % in long-term incubation, meanwhile low-dosage MP reduced soil labile Fe and Mn contents, but high-dosage MP increased their contents. With MP dosages increased, the effects of Fe-Mn oxides on soil labile Cd content gradually weakened. MP effectively promoted the reduction of Fe adsorbed by clay minerals and enhanced their ability to adsorb Cd. Short-term incubation showed that MP could decline soil labile Cd by 7.17 % ∼ 44.74 %, especially at the dosage 0.4 %. MP was a reduction catalyst to facilitate Fe reduction, which profited for clay minerals adsorbing Cd. The sorption experiments indicated that 0.30 % MP could adsorb 73.34 % Cd2+, promote the release of Fe2+ from the soil, and stimulate the ability of clay minerals to adsorb Cd. The results revealed that MP decreased soil labile Cd content within 2 d, and MP made soil Cd activity change out of the influence of soil Fe/Mn redox system. The mechanism will be beneficial for the large-scale application of MP in safe utilization of Cd contaminated soil.


Assuntos
Oryza , Poluentes do Solo , Solo , Cádmio/análise , Poluentes do Solo/análise , Argila , Minerais
18.
Sci Total Environ ; 855: 158710, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36099954

RESUMO

Iron (Fe) oxides are widely recognized to prevent the degradation of organic matter (OM) in environments, thereby promoting the persistence of organic carbon (OC) in soils. Thus, discerning the association mechanisms of Fe oxides and OC interactions is key to effectively influencing the dynamics and extent of organic C cycling in soils. Previous studies have focused on i) quantifying Fe oxide-bound organic carbon (Fe-OC) in individual environments, ii) investigating the distribution and adsorption capacity of Fe-OC, and iii) assessing the redox cycling and transformation of Fe-OC. Furthermore, the widespread application of high-tech instrumentation and methods has greatly contributed to a better understanding of the mechanism of organic mineral assemblages in the past few decades. However, few literature reviews have comprehensively summarized Fe-OC distributions, associations, and characteristics in soil-plant systems. Here, studies investigating the Fe-OC contents among different environments are reviewed. In addition, the mechanisms and processes related to OM transformation dynamics occurring at mineral-organic interfaces are also described. Recent studies have highlighted that diverse interactions occur between Fe oxides and OC, with organic compounds adhering to Fe oxides due to their huge specific surfaces area and active reaction sites. Moreover, we also review methods for understanding Fe-OC interactions at micro-interfaces. Lastly, developmental prospects for understanding coupled Fe-OC geochemical processes in soil environments at molecular- and nano-scales are outlined. The summary suggests that combined advanced techniques and methods should be used in future research to explore micro-interfaces and in situ descriptions of organic mineral assemblages. This review also suggests that future studies need to consider the functional and spatial complexity that is typical of soil/sediment environments where Fe-OC interactions occur.


Assuntos
Óxidos , Solo , Solo/química , Carbono , Minerais/química , Ferro , Compostos Orgânicos/química
19.
Sci Total Environ ; 855: 159003, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36155041

RESUMO

A majority of clay minerals contain Fe, and the redox cycling of Fe(III)/Fe(II) in clay minerals has been extensively studied as it may fuel the biogeochemical cycles of nutrients and govern the mobility, toxicity and bioavailability of a number of environmental contaminants. There are three types of Fe in clay minerals, including structural Fe sandwiched in the lattice of clays, Fe species in interlayer space and adsorbed on the external surface of clays. They exhibit distinct reactivity towards contaminants due to their differences in redox properties and accessibility to contaminant species. In natural environments, microbially driven Fe(III)/Fe(II) redox cycling in clay minerals is thought to be important, whereas reductants (e.g., dithionite and Fe(II)) or oxidants (e.g., peroxygens) are capable of enhancing the rates and extents of redox dynamics in engineered systems. Fe(III)-containing clay minerals can directly react with oxidizable pollutants (e.g., phenols and polycyclic aromatic hydrocarbons (PAHs)), whereas structural Fe(II) is able to react with reducible pollutants, such as nitrate, nitroaromatic compounds, chlorinated aliphatic compounds. Also structural Fe(II) can transfer electrons to oxygen (O2), peroxymonosulfate (PMS), or hydrogen peroxide (H2O2), yielding reactive radicals that can promote the oxidative transformation of contaminants. This review summarizes the recent discoveries on redox reactivity of Fe in clay minerals and its links to fates of environmental contaminants. The biological and chemical reduction mechanisms of Fe(III)-clay minerals, as well as the interaction mechanism between Fe(III) or Fe(II)-containing clay minerals and contaminants are elaborated. Some knowledge gaps are identified for better understanding and modelling of clay-associated contaminant behavior and effective design of remediation solutions.


Assuntos
Poluentes Ambientais , Ferro , Argila , Ferro/química , Peróxido de Hidrogênio , Minerais/química , Oxirredução , Compostos Ferrosos/química , Compostos Férricos/química
20.
J Hazard Mater ; 443(Pt A): 130192, 2023 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-36270191

RESUMO

While extensive works focused on the enhancement of the activity of heterogeneous Fenton catalysts, little was paid attention to the inhibition of soil organic matter (SOM) and Mn minerals in soil remediation. Here, the oxidation of petroleum hydrocarbons in soils (S1: 4.28 % SOM, S2: 6.04 % SOM, S3: 10.33 % SOM) with inactivated SOM and passivated Mn oxides regulating by calcium superphosphate (Ca(H2PO4)2) was carried out. Oily sludge pyrolysis residue was used as precursors to prepare an oleophilic iron-supported solid catalyst (Fe-N @ PR). For regulated systems, under the optimal conditions of 1.8 mmol/g H2O2 and 0.05 g/g Fe-N @ PR, 72 ∼ 91 % of total petroleum hydrocarbons (TPHs: 15,616.58 mg/kg) were oxidized, which was 38 ∼ 45 % higher than that of control systems. The mechanism of efficient oxidation was proposed that the passivated Mn minerals stabilized H2O2 redistributing more H2O2 to sustainably produce •OH, and the inactivated SOM improved the relative reactivity of •OH to TPHs. Additionally, the passivation of Mn oxides was mainly related to the binding of H2PO4-, and the inactivation of SOM was realized by Ca2+ combing with -OH and C-O-C to form stable complexes. This study brought us a new perspective on soil remediation through passivating Mn minerals and inactivating SOM.


Assuntos
Petróleo , Poluentes do Solo , Solo/química , Manganês , Poluentes do Solo/análise , Oxidantes , Peróxido de Hidrogênio/química , Hidrocarbonetos , Oxirredução , Minerais , Óxidos
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