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Enhancing soil organic matter characteristics, ameliorating physical structure, mitigating heavy metal toxicity, and hastening mineral weathering processes are crucial approaches to accomplish the transition of tailings substrate to a soil-like substrate. The incorporation of biomass co-pyrolysis and plant colonization has been established to be a significant factor in soil substrate formation and soil pollutant remediation. Despite this, there is presently an absence of research efforts aimed at synergistically utilizing these two technologies to expedite the process of mining tailings soil substrate formation. The current study aimed to investigate the underlying mechanism of geochemical changes and rapid mineral weathering during the process of transforming tailings substrate into a soil-like substrate, under the combined effects of biomass co-smoldering pyrolysis and plant colonization. The findings of this study suggest that the incorporation of smoldering pyrolysis and plant colonization induces a high-temperature effect and biological effects, which enhance the physical and chemical properties of tailings, while simultaneously accelerating the rate of mineral weathering. Notable improvements include the amelioration of extreme pH levels, nutrient enrichment, the formation of aggregates, and an increase in enzyme activity, all of which collectively demonstrate the successful attainment of tailings substrate reconstruction. Evidence of the accelerated weathering was verified by phase and surface morphology analysis using X-ray diffraction and scanning electron microscopy. Discovered corrosion and fragmentation on the surface of minerals. The weathering resulted in corrosion and fragmentation of the surface of the treated mineral. This study confirms that co-smoldering pyrolysis of biomass, combined with plant colonization, can effectively promote the transformation of tailings into soil-like substrates. This method has can effectively address the key challenges that have previously hindered sustainable development of the mining industry and provides a novel approach for ecological restoration of tailings deposits.
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Biomassa , Mineração , Poluentes do Solo , Solo , Solo/química , Pirólise , Plantas , Biodegradação AmbientalRESUMO
Idebenone, a mitochondrial regulator, has exhibited anti-cancer activity in neurogenic and prostate tumor cells; however, its efficacy and specific targets in the treatment of triple-negative breast cancer (TNBC) remain unclear. This study aims to evaluate the potential of Idebenone as a therapeutic agent for TNBC. TNBC cell lines and Xenograft mouse models were used to assess the effect of Idebenone on TNBC both in vitro and in vivo. To investigate the underlying mechanism of Idebenone's effect on TNBC, cell viability assay, transwell invasion assay, cell cycle analysis, apoptosis assay, mitochondrial membrane potential assay, immunofluorescence staining, and transcriptome sequencing were utilized. The results showed that Idebenone impeded the proliferation, colony formation, migration, and invasion of TNBC cells, suppressed apoptosis, and halted the cell cycle in the G2/M phase. The inhibitory effect of Idebenone on TNBC was associated with the GADD45/CyclinB/CDK1 signaling pathway. By disrupting the mitochondrial membrane potential (MMP) and promoting mitophagy, Idebenone promoted cell autophagy through the AMPK/mTOR pathway, thus further suppressing the proliferation of TNBC cells. Furthermore, we found that Idebenone inhibited the development of TNBC in vivo. In conclusion, Idebenone may be a promising therapeutic option for TNBC as it is capable of inducing autophagy and apoptosis.
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Neoplasias de Mama Triplo Negativas , Ubiquinona/análogos & derivados , Humanos , Animais , Camundongos , Neoplasias de Mama Triplo Negativas/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Proliferação de Células , Linhagem Celular Tumoral , Transdução de Sinais , Modelos Animais de DoençasRESUMO
This study investigates the clinical effects of the novel Traditional Chinese Medicine (TCM) topical wash used in combination with negative pressure irrigation and tadalafil for the treatment of vascular erectile dysfunction. Eighty-seven patients with vascular erectile dysfunction were divided into an observation group and a control group. The observation group was administered negative pressure irrigation (TCM) in combination with oral tadalafil for four weeks, and the control group was administered oral tadalafil for four weeks. The observation group included 21 patients with arterial erectile dysfunction and 22 with intravenous erectile dysfunction. After treatment, IIEF-5, EHS, GAD scores, PSV, EDV and RI in observation group were improved compared with those before treatment (P = 0.000, 0.000, 0.000, L0.000/R0.000, L0.000/R0.000, L0.003/R0.000). Erectile function (IIEF-5, EHS) was significantly improved compared with the control group (P = 0.008, 0.002). In the observation group, there were 21 cases of arterial erectile dysfunction and 22 cases of intravenous erectile dysfunction. After treatment, PSV of arterial ED improved significantly (P = L0.000/R0.000), but EDV did not decrease significantly (P = L0.084/R 0.098). In patients with venous ED, PSV increased (P = L0.026/R0.032) and EDV decreased significantly (P = L0.000/R0.000). These findings suggest that TCM negative pressure lavage combined with tadalafil improves the blood supply of the penile artery, relaxes smooth muscle, and improves the closing mechanism of venous vessels in patients with vascular erectile dysfunction, ultimately improving the erectile function.
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Soil heavy metal pollution is an important issue that affects human health and ecological well-being. In-situ thermal treatment techniques, such as self-sustaining smoldering combustion (SSS), have been widely studied for the treatment of organic pollutants. However, the lack of fuel in heavy metal-contaminated soil has hindered its application. In this study, we used corn straw as fuel to investigate the feasibility of SSS remediation for copper and lead in heavy metal-contaminated soil, as well as to explore the remediation mechanism. The results of the study showed that SSS increased soil pH, electrical conductivity (EC), total phosphorus (TP), total potassium (TK), rapidly available phosphorus (AP), and available potassium (AK), while decreasing total nitrogen (TN), alkali-hydrolyzed nitrogen (AN), and cation exchange capacity (CEC). The oxidation state of copper (Cu) increased from 10% to 21%-40%, and the residual state of lead (Pb) increased from 18% to 51%-73%. The Toxicity characteristic leaching procedure (TCLP) of Cu decreased by a maximum of 81.08%, and the extracted state of Diethylenetriaminepentaacetic acid (DTPA) decreased by 67.63%; the TCLP of Pb decreased by a maximum of 81.87%, and DTPA decreased by a maximum of 85.68%. The study indicates that SSS using corn straw as fuel successfully achieved remediation of heavy metal-contaminated soil. However, SSS does not reduce the content of copper and lead; it only changes their forms in the soil. The main reasons for the fixation of copper and lead during the SSS process are the adsorption of biochar, complexation with -OH functional groups, binding with π electrons, and the formation of crystalline compounds. This research provides a reference for the application of SSS in heavy metal-contaminated soil and has potential practical implications.
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Cobre , Recuperação e Remediação Ambiental , Estudos de Viabilidade , Chumbo , Poluentes do Solo , Cobre/química , Cobre/análise , Chumbo/análise , Chumbo/química , Poluentes do Solo/análise , Poluentes do Solo/química , Recuperação e Remediação Ambiental/métodos , Zea mays/química , Solo/químicaRESUMO
The relationship between microplastics (MPs) and human respiratory health has garnered significant attention since inhalation constitutes the primary pathway for atmospheric MP exposure. While recent studies have revealed respiratory risks associated with MPs, virgin MPs used as plastic surrogates in these experiments did not represent the MPs that occur naturally and that undergo aging effects. Thus, the effects of aged MPs on respiratory health remain unknown. We herein analyzed the interaction between inhalable aged MPs with lung surfactant (LS) extracted from porcine lungs vis-à-vis interfacial chemistry employing in-vitro experiments, and explored oxidative damage induced by aged MPs in simulated lung fluid (SLF) and the underlying mechanisms of action. Our results showed that aged MPs significantly increased the surface tension of the LS, accompanied by a diminution in its foaming ability. The stronger adsorptive capacity of the aged MPs toward the phospholipids of LS appeared to produce increased surface tension, while the change in foaming ability might have resulted from a variation in the protein secondary structure and the adsorption of proteins onto MPs. The adsorption of phospholipid and protein components then led to the aggregation of MPs in SLF, where the aged MPs exhibited smaller hydrodynamic diameters in comparison with the unaged MPs, likely interacting with biomolecules in bodily fluids to exacerbate health hazards. Persistent free radicals were also formed on aged MPs, inducing the formation of reactive oxygen species such as superoxide radicals (O2â¢-), hydrogen peroxide (HOOH), and hydroxyl radicals (â¢OH); this would lead to LS lipid peroxidation and protein damage and increase the risk of respiratory disease. Our investigation was the first-ever to reveal a potential toxic effect of aged MPs and their actions on the human respiratory system, of great significance in understanding the risk of inhaled MPs on lung health.
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Microplásticos , Poluentes Químicos da Água , Animais , Suínos , Humanos , Idoso , Plásticos/toxicidade , Pulmão/metabolismo , Estresse Oxidativo , Tensoativos , Poluentes Químicos da Água/metabolismoRESUMO
OBJECTIVE: To explore the clinical value of the inflammasomes NLRP1 and NLRC4 in the diagnosis and treatment of PCa. METHODS: Using immunohistochemical staining, we detected the expressions of the inflammasomes NLRP1 and NLRC4 and the inflammatory cytokines IL-18 and IL-1ß in 54 cases of BPH and 58 cases of PCa treated in Pinghu First People's Hospital from January 2022 to May 2022. We analyzed the characteristics of their expressions in the two groups of patients and the correlation of NLRP1 and NLRC4 expressions with tPSA, fPSA and Gleason scores in the PCa patients. Based on the Cancer Genome Atlas dataset, we compared the expressions of NLRP1 and NLRC4 in different stages of PCa. RESULTS: The NLRP1 and NLRC4 expressions were significantly increased in the PCa patients (P < 0.001). The expression of NLRP1 was linearly correlated with those of IL-1ß and IL-18 (P < 0.05), and so was the expression of NLRC4 with that of IL-18 (P < 0.05). The expressions of NLRP1 and NLRC4 were positively correlated with the Gleason scores of the PCa patients (P < 0.05), the former remarkably higher in T3 and T4 than in T1 (P > 0.05), and the latter markedly higher in T2, T3 and T4 than in T1 (P < 0.05). CONCLUSION: The inflammasomes NLRP1 and NLRC4 are highly expressed in PCa and facilitate tumorgenesis by promoting the maturation and release of the inflammatory cytokines IL-1ß and IL-18, which indicates their important role in the progression of tumors and clinical value in the risk assessment and prognosis of PCa.
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Inflamassomos , Neoplasias da Próstata , Masculino , Humanos , Inflamassomos/metabolismo , Interleucina-18/metabolismo , Citocinas/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Proteínas NLR/metabolismoRESUMO
The present study explored the clinical value of the protein expression levels of nucleotide binding oligomerization-like receptor family pyrin domain containing 1 (NLRP1) and nucleotide-binding oligomerization domain leucine-rich repeat and caspase recruitment domain-containing 4 (NLRC4) inflammasomes in the diagnosis and treatment of prostate cancer. A total of 54 patients with prostatic hyperplasia and 58 patients with prostate cancer were recruited at The First People's Hospital of Pinghu between January and May 2022. Immunohistochemical staining was used to determine the protein expression levels of the NLRP1 and NLRC4 inflammasomes in addition to the proinflammatory cytokines IL-18 and IL-1ß in the two groups of patients. The protein expression levels of NLRP1 and NLRC4 inflammasome were significantly increased in patients with prostate cancer compared with patients with prostate hyperplasia. The differences in expression of NLRP1 and NLRC4 inflammatory vesicles in prostate cancer of different stages were also compared based on data from The Cancer Genome Atlas. The protein expression level of NLRP1 demonstrated a significant positive correlation with IL-1ß and IL-18 expression, and the protein expression level of the NLRC4 inflammasome was significantly positively correlated with IL-18 expression. The protein expression levels of both NLRP1 and NLRC4 demonstrated a significant positive correlation with the Gleason score of prostate cancer. The expression of NLRP1 in tumor (T)3/T4 was significantly higher compared with T1 and expression of the NLRC4 inflammasome in T2 and T3/T4 was significantly higher compared with T1. Expression of the NLRP1 and NLRC4 inflammasomes was significantly higher in patients with prostate cancer, compared with patients with prostatic hyperplasia. Therefore, expression of NLRP1 and NLRC4 may promote tumorigenesis by promoting the maturation and release of proinflammatory cytokines IL-1ß and IL-18. Expression of the NLRP1 and NLRC4 inflammasomes demonstrated a significant positive correlation with the risk of prostate cancer. Expression of the NLRP1 and NLRC4 inflammasomes in middle- and advanced-stage tumors was higher compared with early-stage tumors. These results suggested that inflammasome expression may serve a significant role in the progression of tumors and could provide a fixed value for the risk assessment and prognosis prediction of prostate cancer.
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Copper oxide nanoparticles (CuO NPs) can adversely affect lung health possibly by inducing oxidative damage through the release of copper ions. However, the migration and transformation processes of CuO NPs in lung lining fluid is still unclear, and there are still conflicting reports of redox reactions involving copper ions. To address this, we examined the release of copper ions from CuO NPs in simulated lung fluid supplemented with pulmonary surfactant (PS), and further analyzed the mechanisms of PS-CuO NPs interactions and the health hazards. The results showed that the phospholipid of PS was adsorbed on the particle surface, which not only induced aggregation of the particles but also provided a reaction environment for the interaction of PS with CuO NPs. PS was able to promote the release of ions from CuO NPs, of which the protein was a key component. Lipid peroxidation, protein destabilization, and disruption of the interfacial chemistry also occurred in the PS-CuO NPs interactions, during which copper ions were present only as divalent cations. Meanwhile, the contribution of the particle surface cannot be neglected in the oxidative damage to the lung caused by CuO NPs. Through reacting with biomolecules, CuO NPs accomplished ion release and induced oxidative damage associated with PS. This research was the first to reveal the mechanism of CuO NPs releasing copper ions and inducing lipid oxidative damage in the presence of PS, which provides a new idea of transition metal-induced health risk in human body.
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The total de-alkalization treatment of industrial solid waste red mud (RM) has been a worldwide challenge. Removing the insoluble structural alkali fraction from RM is the key to enhancing the sustainable utilization of RM resources. In this paper, supercritical water (SCW) and leaching agents were used for the first time to de-alkalize the Bayer RM and to remove sulfur dioxide (SO2) from flue gas with the de-alkalized RM slurry. The results showed that the optimum alkali removal and Fe leaching rates of RM-CaO-SW slurry were 97.90 ± 0.88% and 82.70 ± 0.95%, respectively. Results confirmed that the SCW technique accelerated the disruption of (Al-O) and (Si-O) bonds and the structural disintegration of aluminosilicate minerals, facilitating the conversion of insoluble structural alkalis to soluble chemical alkalis. The exchangeable Ca2+ displaced Na+ in the remaining insoluble base, producing soluble sodium salts or alkalis. CaO consumed SiO2, which was tightly bound to Fe2O3 in RM, and released Fe2O3, which promoted Fe leaching. RM-SCW showed the best desulfurization performance, which maintained 88.99 ± 0.0020% at 450 min, followed by RM-CaO-SW (450 min, 60.75 ± 6.00%) and RM (180 min, 88.52% ± 0.00068). The neutralization of alkaline components, the redox of metal oxides, and the liquid-phase catalytic oxidation of Fe contributed to the excellent desulfurization performance of the RM-SCW slurry. A promising approach shown in this study is beneficial to RM waste use, SO2 pollution control, and sustainable growth of the aluminum industry.
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Dióxido de Silício , Água , Água/química , Resíduos Industriais , Alumínio , ÓxidosRESUMO
Self-sustaining smoldering is an emerging technology for nonaqueous-phase liquid remediation; however, it is rarely applied for Cr(VI)-contaminated soil treatment. In this study, self-sustaining smoldering using rice straw (RS) as a surrogate fuel was applied to remediate Cr(VI)-contaminated soil for the first time. Thirteen one-dimensional vertical smoldering experiments were conducted to investigate the effectiveness of the smoldering method and the effects of key experimental parameters on smoldering remediation performance. Smoldering was observed to be self-sustaining within the range of RS particle size from <0.16 to 2.00-4.00 mm, airflow from 0.2 to 1 m3/h, and Cr(VI)-impacted soil/RS ratios from 2:1 to 6:1. The Cr(VI)-contaminated soil was effectively remediated, which was confirmed by lowered Cr(VI) contents in the treated samples (decreased by 52.22-86.57%) and the elevated fraction of Cr oxidizable and residual form (increased by 1.14-3.30 and 2.97-4.00 times, respectively), compared to the control. The reducing gases (CO and CxHy) generated during the smoldering played a crucial role in the remediation process. The contents of available P and K in the remediated soil containing the remaining biochar and ash increased, thus improving soil reusability. Hence, this study shows that smoldering with RS as supplemental fuel is a promising Cr(VI)-contaminated soil management technique without supplying substantial external energy.
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Recuperação e Remediação Ambiental , Poluentes do Solo , Cromo/análise , Poluição Ambiental , Solo , Poluentes do Solo/análiseRESUMO
Acid mine drainage (AMD) is a well-recognized environmental issue associated with mining production worldwide. The second part of our study aims to assess the protective effect of using a polymer hard layer (PHL) by conducting sulphur-enriched tailing-based column experiments. An oxygen (O2) barrier was simulated using a designed column device filled with different types of tailings. All experimental columns underwent six drying-wetting cycles, and the chemical properties of the tailings and leachate were detected after every cycle. The permeability coefficient of the PHL was only 1.16 × 10- 5 cm/s. Over the entire experimental period, none of the leachates collected from column 4 using the PHL as an O2 barrier. Moreover, the level of redox potential and pH and the contents of heavy metals such as Cu and Zn were stable in PHL covering system. These results show that a PHL is the optimal covering system.
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Metais Pesados , Polimerização , Mineração , OxirreduçãoRESUMO
Acid mine drainage (AMD) has caused a great impact on soil, surface water, groundwater, plants or other organisms in the mining environment because of its high acidity, high sulphate content, and contains a variety of heavy metals. AMD treated by carbonate rocks have been regarded as a feasible technology for pollution control and applied widely in mine area. However, to date, the kinetics of the reaction between carbonate rock and AMD have not been investigated, resulting in the lack of systematic theoretical guidance for the implementation of this technology. In this study, effects of carbonate particle sizes and reaction temperature on AMD treatment were investigated. The dissolution efficiency of Ca2+ was used to quantitatively reflect extent of reaction, and the leaching kinetics was analysed based on the shrinking core model. The results showed that carbonate rocks with a particle size of 0.5-1.0â mm had the best pH-enhancing performance for AMD and highest removal efficiency for Fe3+ (>98.00%), while the Mn2+ and SO42- were temperature sensitive. The diffusion of solid product layer was the controlling step of the leaching reaction, and the apparent activation energy of the reaction was 12.63â kJ·mol-1.
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This article systematically examines the physical characteristics, group composition characteristics, and geochemical characteristics of heavy oil in the Western Sag of the Liaohe Basin. The examination is based on the separation and quantitative analysis of crude oil and rock samples, as well as the analysis of test results from gas chromatography with saturated hydrocarbons and aromatic hydrocarbons. It also analyzes the generation mechanism and main controlling factors of heavy oil. The results show that heavy oil has low wax content (1.8-9.2%), a low freezing point (-19-38 °C), low sulfur content (0.28-0.5%), high colloid and asphaltene content, high density (0.926-1.008 g/cm3), and high viscosity (328-231910 mPa·s). The physical properties of the heavy oil in the same formation decrease from the depression's edge toward its center and within the same area, and the physical properties in different formations also have an inverse relationship with burial depth. Biodegradation is the main reason for the formation of heavy oil. Based on the biodegradation degree, there are four types of heavy oil: undegraded, weakly degraded, moderately degraded, and severely degraded. The main controlling factors of biodegradation are temperature and the water environment. This study provides a method for studying the genetic mechanism of heavy oil, an approach for discovering similar genetic oil and gas, and a basis for the transformation of heavy oil field development.
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Aim: Evidence on the association between natural-built environments and depression is largely derived from the general population and prone to residential self-selection bias because of the nature of cross-sectional research design. Despite emerging adulthood, which includes the university years, is a critical stage for forming life-long health habits, studies on this topic focusing on undergraduate students are limited. The current study aims to illustrate the underlying mechanisms for how the campus-based environments affect depression in undergraduate students. Methods: Based on a nationwide representative analytical sample of 22,009 Chinese undergraduates in 2018, we examined participants' reports of depression and campus-centered natural/built environments within multiple buffer sizes including 0.5, 1.0, and 2.5 km. After disentangling residential self-selection, we explored the moderating role of the socioeconomic attributes of undergraduates. The depression outcome was measured by the nine-item Patient Health Questionnaire (PHQ9). Indicators of exposure to green and blue space, transportation infrastructure, and food environments were objectively assessed using different circular buffers around each campus address. Results: Modeling results indicated that campus neighborhoods with more scattered trees (0.5 km), water (0.5, 1.0, and 2.5 km), and street intersections (1.0 and 2.5 km) were protective against depression. In contrast, those living near denser distributions of outlets serving take-away sweets and fast food (0.5, 1.0, and 2.5 km) were susceptible to depression. These associations were modified by undergraduates' socioeconomic attributes (e.g., grade, Hukou status, and ethnicity) and varied according to geographical scales and exposure metrics. Conclusion: To deliver effective environmental interventions to curb the prevalence of depression among undergraduate students, further planning policies should focus on the careful conception of the campus-based environment, especially regarding different spatial scales.
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Ambiente Construído , Depressão , Adulto , China/epidemiologia , Estudos Transversais , Depressão/epidemiologia , Humanos , Fatores Socioeconômicos , EstudantesRESUMO
Polycyclic aromatic hydrocarbons (PAHs) can penetrate and accumulate in the pulmonary surfactant (PS) membranes, leading to abnormalities of biological macromolecules and the destruction of membrane structure and properties. In the present study, the bioavailability, apparent permeability, effective permeability and residual coefficient of 10 PAHs on PS membrane was assessed by the parallel artificial membrane permeability assay (PAMPA). The influence of various forces on permeability is obtained by analyzing the correlation between parameters and physicochemical properties. Research shows that octanol-water partition coefficient (Kow) cannot directly predict permeability, and permeability has no significant relationship with polarity. Dispersion, induction, coupling/polarization promote permeation, while hydrogen bonded acid and n-n electron pair inhibit permeation. Further surface pressure-area (π-A) isotherms test and Brewster angle microscope observation manifested that there are huge differences in the transmembrane ability and effects on the membrane of PAHs with different structures. This work has considerable significance that will help to evaluate the bioavailability and human health risk of PAHs.
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Hidrocarbonetos Policíclicos Aromáticos , Surfactantes Pulmonares , Poluentes Químicos da Água , Humanos , Membranas Artificiais , Permeabilidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Poluentes Químicos da Água/análiseRESUMO
Acid mine drainage, produced from sulfur-containing mine waste exposed to air, water, and bacteria, is considered as a serious environmental pollutant because of its extremely low pH and excessive heavy metals. In order to solve the ecological environment problems caused by the acid mine drainage, treatment methods such as neutralization, adsorption, passivation, bio-inhibition, and physical coverage have been developed. Nevertheless, these methods are terminal treatment methods, which are unable to prevent the generation of acid mine drainage at the source. Recently, it is noteworthy that the tailing covering technology is particularly emphasized, owing to its superior source control capability. By reducing the contact with air, water, and bacteria, the oxidation of sulfide tailings is significantly reduced, thus avoiding the production of acid mine drainage. To date, massive research has been studied and parts of technologies have been applied, but the review on the principles, processes, and applications of these technologies are still lacking. Thus, the present review aims to increase the knowledge related to the most relevant application of tailing covering technology with the following aspects: (i) the background, concepts, and performance of tailing covering technology; (ii) the applicable conditions for each tailings coverage system and their advantages and limitations; and (iii) the future perspective of this technology.
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Acid mine drainage (AMD) is a serious and persistent environmental pollution problem. At present, many studies have focused on the tailings pond's cover systems. This paper introduced the research results of using tin tailings from Laili mountain to make the covering layer of tailings pond. The first part included a detailed description of tailings characterization and acid production potential. On this basis, the hard layer (HL) was prepared and its feasibility as oxidation barrier was evaluated. It was found that when the proportion of tailings waste was 70%, the immobilization efficiency of heavy metals can reach more than 99.45%, and the pH of leaching solution was about 10.8. Moreover, the beneficial effect of solid waste addition on the HL was also verified. This suggests that HL as a post-mining restorative strategy has strong positive influence on pollution control.
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Metais Pesados , Mineração , Poluição Ambiental , Geologia , Metais Pesados/análise , PolimerizaçãoRESUMO
Sulfide-containing mine waste was oxidized to produce acid mine drainage, which lead to acidification of surrounding soil and downstream rivers and posed a threat to the surrounding environment. Quartz often coexists with sulfide minerals and affects the oxidation of sulfide minerals. In order to explore the role of quartz in the bio-oxidation of sulfide minerals in mine solid waste, the mixed minerals of quartz and sulfide minerals were bio-oxidized by Acidithiobacillus ferrooxidans. The results showed that quartz could improve the microbial activity and increase the acid production of sulfide minerals. The larger the proportion of quartz in bio-oxidation of sulfide minerals, the less the production of secondary minerals such as jarosite, and the larger the leaching amount of iron and sulfate. This research provides new ideas for speeding up the bio-oxidation of sulfide mineral to remove iron and sulfate. It provides a new way to solve acid pollution caused by oxidation of sulfide minerals.
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Quartzo , Resíduos Sólidos , Acidithiobacillus , Minerais , Oxirredução , SulfetosRESUMO
Inhaled polycyclic aromatic hydrocarbons (PAHs) can directly interact with the lung surfactant (PS) lining of alveoli, thereby affecting the normal physiological functions of PS, which is a serious threat to lung health. In spite of the extensive study of benzo[a]pyrene (BaP, a representative of PAHs), its potential biophysical influence on the natural PS is still largely unknown. In this study, the interfacial interaction between PS (extracted from porcine lungs) and BaP is investigated in vitro. The results showed that the surface tension, phase behavior, and interfacial structure of the PS monolayers were obviously altered in the presence of BaP. A solubilization test manifested that PS and its major components (dipalmitoyl phosphatidylcholine, DPPC; bovine serum albumin, BSA) could in turn accelerate the dissolution of BaP, which followed the order: PS > DPPC > BSA, and mixed phospholipids were significantly responsible for the solubilization of BaP by PS. In addition, solubilization of BaP also enhanced the consumption of hydroxyl radicals (·OH) in the simulated lung fluid, which could disturb the balance between oxidation and antioxidation.
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Hidrocarbonetos Policíclicos Aromáticos , Surfactantes Pulmonares , Animais , Benzo(a)pireno/toxicidade , Pulmão , Alvéolos Pulmonares , SuínosRESUMO
Silicate-iron oxyhydroxide complex formed by mineral weathering has an important influence on the geochemical reactions of heavy metals in mining areas. In this work, tailings were collected from an abandoned iron tailings pond, and the physicochemical properties and distribution of heavy metals were studied under natural weathering and hydraulic processes. The results showed that Fe2+ in the iron tailings were transported to the surface during the weathering process, and then the iron oxyhydroxide formed by mineralization adsorbed Cu2+ and Zn2+. Silicic acid and exchangeable acid were released during the formation of binary agglomerates between hydroxy iron oxide and kaolin, then they migrated to the lower area of a tailing pond via surface runoff. Finally, silicate-iron oxyhydroxide complex were formed. The heavy metals were replaced by H+ and penetrated to the bottom layer with water. This research provides an important scientific basis for the prevention and control of heavy metal pollution in mining areas.