Explore the vast range of titles available.

Rapid, accurate detection of heavy-metal content is extremely important for precise risk control and targeted remediation. Herein, a general modeling method and process based on the relationship between Pxrf measured values and site parameters are explored to construct a Pxrf correction model suitable to improve each site’s measurement accuracy. Results show a significant correlation between Pb, Mn, and Zn Pxrf measured values and actual concentrations, with correlation coefficients between 0.8 and 0.93. Through the correlation analysis, the correlation coefficient between the water content and the measured value of pxrf is in the range of 0.2–0.5. Pxrf measurement of all heavy metals was weakly affected by soil organic matter content, with correlation coefficients all lower than 0.5. Model transformation effectively improved the correlation between measured Pxrf value and actual concentration, and transformation increased the correlations of Sr, Mn, and Cu by around 0.11. Model verification results showed that the Pb, Zn, Fe, and Mn models can be used to improve Pxrf method detection accuracy.

Long-term open-air storage of coal gangue (CG) can generate leachates containing oxidizable components contributing to chemical oxygen demand (COD), together with sulfate (SO42−) and fluoride (F−), yet their source-term behavior remains poorly understood. In this study, batch and column leaching tests were conducted on multi-source CG samples and combined with ToF-SIMS (surface compositional mapping), solid-phase TOC gradient leaching, and PHREEQC-XGBoost-SHAP modeling (coupled geochemical–machine learning analysis). Batch-leachate COD levels ranged from 4.6 to 68.0 mg/L, while SO42− and F− concentrations reached maxima of approximately 317 and 1.29 mg/L, respectively. During column leaching, COD levels and SO42− concentrations were highest at low liquid-to-solid ratios (L/S) and subsequently decreased, with maximum initial values of 186.6 and 3074 mg/L, respectively, whereas F− exhibited delayed and persistent release at approximately 0.3–2.3 mg/L. Solid-phase TOC did not directly predict the COD response, and ToF-SIMS revealed aliphatic organic fragments associated with aluminosilicate surfaces that weakened or were redistributed after leaching. The COD–DOC discrepancy further indicated that dissolved organic matter alone could not fully explain the COD response, although the possible contribution of inorganic reducing species requires direct verification. Within the modeled framework, the sulfate source-term coefficient accounted for 69.4–76.9% of the modeled influence at L/S = 0.5–2.0 L/kg, while the influence of the HFO surface complexation increased during later leaching. In contrast, the F− source-term coefficient remained dominant over L/S = 0.5–10.0 L/kg, accounting for 97.0–97.9% of the modeled influence. These findings support parameter- and stage-specific monitoring and pollution control at CG disposal sites.

Molecular chaperones, a class of complex client regulatory systems, play significant roles in the prevention of protein misfolding and abnormal aggregation, the modulation of protein homeostasis, and the protection of cells from damage under constantly changing environmental conditions. As the understanding of the biological mechanisms of molecular chaperones has increased, their link with the occurrence and progression of disease has suggested that these proteins are promising targets for therapeutic intervention, drawing intensive interest. Here, we review recent advances in determining the structures of molecular chaperones and heat shock protein 90 (HSP90) chaperone system complexes. We also describe the features of molecular chaperones and shed light on the complicated regulatory mechanism that operates through interactions with various co-chaperones in molecular chaperone cycles. In addition, how molecular chaperones affect diseases by regulating pathogenic proteins has been thoroughly analyzed. Furthermore, we focus on molecular chaperones to systematically discuss recent clinical advances and various drug design strategies in the preclinical stage. Recent studies have identified a variety of novel regulatory strategies targeting molecular chaperone systems with compounds that act through different mechanisms from those of traditional inhibitors. Therefore, as more novel design strategies are developed, targeting molecular chaperones will significantly contribute to the discovery of new potential drugs.

Heavy metals and polycyclic aromatic hydrocarbons (PAHs) are the important contaminants in used mineral oil (UMO) and likely pose environmental risks in the processes of disposal and regeneration. However, little information on the concentrations and associated with the risk of heavy metals and PAHs in various types of UMO from different industries is available. In this study, the occurrence of heavy metals and PAHs in the UMOs from typical industries in China was investigated. The median concentrations of 12 metals were 0.1–28 mg/kg. PAHs were mainly composed of 2- and 3-ring compounds and the median concentrations of 16 PAHs were 0.03–7.6 mg/kg in different UMO. The cluster analysis showed that samples with high heavy metal and PAH concentrations mainly originated from machine manufacturing and vehicle industries. The random forest model suggested that the species and phase of UMO were the main influencing factors associated with heavy metal concentrations, and the relative importance was 71.1–19.9%, 100–30.7%, 42.3–20.7%, 38.0–11.8%, and 100–24.1% for Cu, Zn, Ni, Cr, and Pb models, respectively, while industry was the main influencing factor associated with PAHs in UMO, and the relative importance was 81.5–51.5%, 27.7–16.5%, 83.4–25.3%, 94.8–21.4%, and 53.3–16.1% for 2- to 6-ring models, respectively.

With the growth of the industrial aluminum smelting sector, and the increasing proportion of incineration treatment in the field of waste management and disposal, there has been a corresponding increase in the production of secondary aluminum dross (SAD) and municipal solid waste incineration fly ash (MSWIFA) annually. In this research, ceramsite is prepared using SAD, MSWIFA, and municipal solid waste incineration bottom ash (MSWIBA) as raw materials. This study explores the impact of various factors on the mechanical properties of ceramsite and their mechanisms under different conditions, including sintering temperature, raw material ball particle size, raw material silica-alumina ratio, and sintering time. Single-factor experiments demonstrate that the compressive strength of ceramsite initially follows a non-linear ascending trend with increasing sintering temperatures. Additionally, the strength is enhanced with reductions in particle size of the raw material balls, prolongation of the sintering time, and a reduction in the silica-to-alumina ratio of the raw materials. Orthogonal experiments reveal the ideal preparation conditions for ceramsite as follows: a preheating temperature of 400 °C, a preheating duration of 20 min, a sintering temperature of 1270 °C, and a duration of 30 min. Under these conditions, the optimal composition ratio of ceramsite is Si:Al = 3, and the ideal particle size is 0.5 cm. Analysis through X-ray diffraction and scanning electron microscopy revealed the formation of new mineral phases such as sodium feldspar and potassium feldspar in the ceramsite, which display a dense structure under microscopic observation. These contribute positively to the mechanical properties of the ceramsite. Fourier-transform infrared spectroscopy analysis indicates that at a sintering temperature of 1260 °C or when the raw material ball size is 2 cm, the [SiO 4 ] tetrahedral bands shift to higher wavenumbers, enhancing the degree of polymerization of the glass network in the ceramsite, thereby strengthening its compressive strength. As the silica-alumina ratio of the raw materials decreases and the sintering duration extends, the [SiO 4 ] tetrahedral bands continue to shift to higher wavenumbers, further enhancing the compressive strength of the ceramsite.

Road dusts were collected from an area where intense mechanical recycling of plastic wastes occurs in Wen’an, north China. These dusts were investigated for polybrominated diphenyl ethers (PBDEs) and heavy metals contamination to assess the health risk related to these components. Decabromodiphenyl ether (BDE-209) and Σ₂₁PBDE concentrations in these dusts ranged from 2.67 to 10,424 ng g⁻¹ and from 3.23 to 10,640 ng g⁻¹, respectively. These PBDE concentrations were comparable to those observed in road dust from e-waste recycling areas but were 1–2 orders of magnitude higher than concentrations in outdoor or road dusts from other areas. This indicates that road dusts in the study area have high levels of PBDE pollution. BDE-209 was the predominant congener, accounting for 86.3 % of the total PBDE content in dusts. Thus, commercial deca-BDE products were the dominant source. The average concentrations of As, Cd, Cr, Cu, Hg, Pb, Sb, and Zn in these same dust samples were 10.1, 0.495, 112, 54.7, 0.150, 71.8, 10.6, and 186 mg kg⁻¹, respectively. The geoaccumulation index suggests that road dusts in this area are moderately to heavily polluted with Cd, Hg, and Sb. This study shows that plastic waste processing is a major source of toxic pollutants in road dusts in this area. Although the health risk from exposure to dust PBDEs was low, levels of some heavy metals in this dust exceeded acceptable risk levels for children and are of great concern.

Threats from landfill leachate leakage to groundwater quality in remote areas is a major concern globally. Buffering distance (BFD) maintained between landfill site and groundwater supply wells is important to prevent drinking water from contamination of hazardous pollutant. Ignoring the leakage increase in the end of landfill life leads to an underestimate of BFD demand, posing potential threat to drinking safety. This paper constructs a framework for BFD prediction with the consideration of landfill performance degradation by coupling landfill performance evaluation model with the aging and defect evolution model of landfill engineering materials, and carries out model application and verification in a coastal hazardous waste landfill. The results show that during the life cycle of a landfill, its BFD experienced a 1.5-time increase from the start of its operation to its life end and reached 3000 m. Under the condition of landfill performance degradation, the BFDs required to attenuate heavy metals experience more increase than those of organic pollutants; BFD required for zinc (Zn), for example, increases 720 m over the no-degradation condition, while 2,4-dichlorophenol(2,4-D) increases by only 288 m. Considering the uncertainty sourced from model parameter and structure, the BFD should be more than 4050 m to ensure long-term safe drinking under unfavorable conditions such as large amount of leachate, weak degradation and fast diffusion of pollutant in vadose and aquifer. If the BFD cannot meet the demand at the end of the landfill life, the leaching behavior of solid waste can be controlled to reduce it depending on BFD. For example, when the leaching concentration of Cd in the waste is reduced from 0.6 mg/L to 0.17 mg/L, the buffering distance is be reduced from 3000 m to 500 m.

With economic development, the quantity of solid waste is increasing rapidly in China; the total quantities of municipal solid waste (MSW), industrial solid waste (ISW), and hazardous waste (HW) in 2002 were 136.5 million tons, 945 million tons, and 10 million tons, respectively. In 2002, the quantity of MSW disposed of was 74.04 million tons, 89.30% of which was landfilled, 3.72% was incinerated, and 6.98% was composted. There are currently 651 disposal facilities for MSW in China. Mining gangue is the largest component of ISW, making up 27.5% of the total. In the Chinese industrial sector, the coal mining and processing industry contributed most to the total quantity of ISW, with 16.0% of the total quantity of ISW generated by this sector. In total, 44% of HW was recycled, 27% was stored, 13.5% was disposed of, and 15.4% was discharged. Of the total HW generated, 40% was produced by the chemical materials and chemical products industry. Five categories of HW, i.e., waste alkali, waste acid, inorganic fluoride waste, copper waste, and inorganic cyanide waste, made up 57.8% of the total HW generated. Solid waste pollution has become a huge challenge faced by those involved in Chinese environmental management, but this can be seen as an opportunity to improve environmental quality. This article introduces the strategies taken to improve solid waste management in China.

Crops could accumulate trace metals by soil-root transfer and foliar uptake from atmospheric fallout, and an accurate assessment of pollution sources is a prerequisite for preventing heavy metal pollution in agricultural products. In this study, we examined Pb isotope rates to trace the sources of Pb in wheat grain grown in suburbs. Results showed that, even in zones with scarcely any air pollution spots, atmospheric fallout was still a considerable source of Pb accumulation in wheat. The concentration of Pb in wheat grain has poor correlation with that in farm soil. The Pb concentration in wheat grains with dust in bran coat was significantly higher than that in wheat grains, which indicates that Pb may accumulate by foliar uptake. The Pb isotope rate has obvious differences between the soil and atmospheric fallout, and scatter ratio is significantly closer between the wheat grain and atmospheric fallout. Atmospheric fallout is a more significant source of Pb concentration in wheat grains than in soil. As far as we know, this is the first study on the main sources of lead in grain crop (wheat) samples with isotope. This study aims to improve our understanding of the translocation of foliar-absorbed metals to nonexposed parts of plants.