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Single‐component epoxy adhesives are widely used in various fields due to their simple operation process and excellent bonding properties. However, the excessively high curing temperature of the traditional single‐component epoxy adhesives may easily damage the electronic devices, limiting their further application. Hence, it is of great significance to develop the low‐temperature‐curing single‐component epoxy adhesives. However, the room temperature storage stability of low‐temperature curing system is generally poor. This work selected epoxy resin (EPON‐828), pentaerythritol tetra (3‐mercaptopropionate) (PETMP), 1‐benzylimidazole (1‐BMZ), and stabilizer (salicylic acid) as materials to prepare low‐temperature curing single‐component epoxy adhesives. In order to improve the storage stability of the system, polycarbonate (PCM‐A‐37) with low molecular weight was employed to coat the accelerator 1‐BMZ by physical sedimentation. The results showed that the room temperature storage period of the system reached 140 h, which was 2.18 times longer than before coating, and the curing temperature of 75°C was determined through DSC curves fitting. The epoxy adhesives have been completely cured at 75°C for 5 h, and shear strength reached 10.20 ± 0.51 MPa, which was not significantly different from that of the system with uncoated accelerators. We believe our paradigm can provide a feasible approach for preparing low‐temperature curing single‐component epoxy adhesives, and has reference significance for the preparation of single‐component adhesives in other systems, too. [ABSTRACT FROM AUTHOR]

As the energy demand increases, there is a significant expansion and utilization of oil resources, resulting in the inevitable occurrence of environmental pollution. Oil has been identified as a prevalent soil contaminant, posing substantial risks to the soil ecosystems. The remediation of soil contaminated with oil is a formidable undertaking. Increasing evidence shows that chemical washing, a remediation technique employing chemical reagents like surfactants to augment the solubilization, desorption, and separation of petroleum hydrocarbons in soil, proves to be an efficacious approach, but the latest advances on this topic have not been systematically reviewed. Here, we present the state of knowledge about the surfactant-based chemical washing to remediate oil-contaminated soil. Using the latest data, the present article systematically summarizes the advancements on ex situ chemical washing of oil pollution and provides a concise summary of the underlying principles. The use of various surfactants in chemical washing and the factors influencing remediation efficiency are highlighted. Based on the current research status and knowledge gaps, future perspectives are proposed to facilitate chemical washing of oil-polluted soil. This review can help recognize the application of chemical washing in the remediation of oil-polluted soil. [ABSTRACT FROM AUTHOR]

The network fracturing technique is a key technology for increasing effective reservoir volume and enhancing production in shale oil and gas. The fracture network's conductivity is one of the crucial factors affecting the efficient development of shale gas. To evaluate the variation patterns and influencing factors of the conductivity of network fractures, this study employed a proppant conductivity evaluation system and an equivalent theory testing method. It investigated the conductivity of propped and self-propped fractures under different angles and numbers of fractures. Experimental results showed that fractures with proppant support had higher conductivity than unsupported fractures. Smaller angles between secondary and main fractures resulted in greater conductivity. The conductivity of multi-fracture structures increased with the number of fractures. Under low-closure pressure conditions, self-propped fractures exhibited significantly higher conductivity than propped fractures, but this trend reversed under high closure pressure. This experimental research provides guidance for constructing network fractures with high conductivity in unconventional oil and gas reservoir fracturing. [ABSTRACT FROM AUTHOR]

Background: Paraquat (PQ) is a pesticide, exposure to which has been associated with an increased risk of Parkinson's disease; however, PQ transport mechanisms in the brain are still unclear. Our previous studies indicated that the organic cation transporter 3 (OCT3) expressed on astrocytes could uptake PQ and protect the dopaminergic (DA) neurons from a higher level of extracellular PQ. At present, it is unknown how OCT3 levels are altered during chronic PQ exposure or aging, nor is it clear how the compensatory mechanisms are triggered by OCT3 deficiency. Dynamic related protein 1 (DRP1) was previously reported to ameliorate the loss of neurons during Parkinson's disease. Nowadays, mounting studies have revealed the functions of astrocyte DRP1, prompting us to hypothesize that DRP1 could regulate the PQ transport capacity of astrocytes. Objectives: The present study aimed to further explore PQ transport mechanisms in the nigrostriatal system and identify pathways involved in extracellular PQ clearance. Methods: Models of PQ-induced neurodegeneration were established by intraperitoneal (i.p.) injection of PQ in wild-type (WT) and organic cation transporter-3-deficient ([Oct3.sup.-/-]) mice. DRP1 knockdown was achieved by viral tools in vivo and small interfering RNA (siRNA) in vitro. Extracellular PQ was detected by in vivo microdialysis. In vitro transport assays were used to directly observe the functions of different transporters. PQ-induced neurotoxicity was evaluated by tyrosine hydroxylase immunohistochemistry, in vivo microdialysis for striatal DA and behavior tests. Western blotting analysis or immunofluorescence was used to evaluate the expression levels and locations of proteins in vitro or in vivo. Results: Older mice and those chronically exposed to PQ had a lower expression of brain OCT3 and, following exposure to a 10-mg/kg i.p. [PQ.sup.2+] loading dose, a higher concentration of extracellular PQ. DRP1 levels were higher in astrocytes and neurons of WT and [Oct3.sup.-/-] mice after chronic exposure to PQ; this was supported by finding higher levels of DRP1 after PQ treatment of dopamine transporter- expressing neurons with and without OCT3 inhibition and in primary astrocytes of WT and [Oct3.sup.- /-] mice. Selective astrocyte DRP1 knockdown ameliorated the [PQ.sup.2+]-induced neurotoxicity in [Oct3.sup.-/-] mice but not in WT mice. GL261 astrocytes with siRNA- mediated DRP1 knockdown had a higher expression of alanine-serine-cysteine transporter 2 (ASCT2), and transport studies suggest that extracellular PQ was transported into astrocytes by ASCT2 when OCT3 was absent. Discussion: The present study mainly focused on the transport mechanisms of PQ between the dopaminergic neurons and astrocytes. Lower OCT3 levels were found in the older or chronically PQ-treated mice. Astrocytes with DRP1 inhibition (by viral tools or mitochondrial division inhibitor-1) had higher levels of ASCT2, which we hypothesize served as an alternative transporter to remove extracellular PQ when OCT3 was deficient. In summary, our data suggest that OCT3, ASCT2 located on astrocytes and the dopamine transporter located on DA terminals may function in a concerted manner to mediate striatal DA terminal damage in PQ-induced neurotoxicity. https://doi.org/10.1289/EHP9505, Introduction Paraquat [1,1'-dimethyl-4,4'-bipyridinium dichloride (PQ)], as one of the widely used broad-spectrum cationic herbicides, (1-3) has been associated with a variety of toxicities, including pulmonary, (4) neuro-, (5) and nephrotoxicity. [...]

The stomatal complex on the surface of maize leaves is closely related to photosynthesis and transpiration, and the study of maize stomatal phenotypes and the discovery of their regulatory genes are of great importance for the breeding of high-quality and high-yielding maize. In this study, rapid scanning electron microscopy was used to obtain images of the abaxial stomata of 457 maize inbred lines with extensive genetic variation, and stomata density was obtained by counting. The results of correlation showed that stomata density was significantly correlated with leaf width, and Analysis of variance found that there were significant differences (P value < 0.05) in stomata density among different leaf width and 100-grain weight. The highest stomata density was found in the inbred lines with wide and short leaves and higher 100-grain weight. Furthermore, genome-wide association analysis was performed using a mixed linear model. It showed that eight SNPs significantly associated with stomata density were obtained, which could explain 35.507% of the phenotypic variation. Among these, four SNPs on chromosome 5 were tightly linked, mainly formatting two haplotypes, CTTA (0.636) and TCCG (0.330). Twelve genes with functional annotation were identified within 100 kb upstream and downstream of the eight SNPs. One gene, GRMZM2G068277, which had been shown to be involved in plant mitotic processes and exhibited high expression at the leaf base, was therefore the most likely candidate gene for stomata density. The results presented here could provide references for further cloning of functional genes related to stomata density. [ABSTRACT FROM AUTHOR]