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Although freeze–thaw damage to rocks has been extensively studied in recent decades, the quantitative correlation between the microscopic pores and macroscopic physico-mechanical properties of rocks under freeze–thaw action has not yet been determined. In this study, the pore structure variation in three sandstones during the freeze–thaw process was continuously measured by the mercury intrusion porosimetry (MIP) test. The pore size distribution can be characterized by a multimodal exponential function. With increasing freeze–thaw cycles, the characteristic pore radii of the nanopores (d ≤ 5 × 10−5 mm), micropores (5 × 10−5 mm ≤ d ≤ 0.1 mm), and macropores (0.1 mm ≤ d ≤ 1 mm) increase. However, the volumetric fractions of nanopores and micropores decrease continuously during freeze–thaw cycles because a considerable number of nanopores and micropores develop into macropores. The fractal dimension of the pore structure gradually decreases as the number of freeze–thaw cycles increases. This implies that the pore size distribution gradually tends to be more homogeneous and that the complexity of the pore structure decreases. Finally, the relationship between microscopic pore structure parameters and macroscopic properties (porosity, P-wave velocity, and uniaxial compressive strength) was established. Through the analysis of microscopic structure evolution and loss of macroscopic properties, it can be concluded that the growth of macropores may play a dominant role in freeze–thaw damage and strength loss. This study can provide a better understanding of the macro-microscopic freeze–thaw damage mechanism of sandstones. [ABSTRACT FROM AUTHOR]

[Display omitted] • Persulfate usually needs to be activated for efficient WAS treatment. • Fermentation/digestion is improved as persulfate boosts bioprocesses and community. • Persulfate promotes sludge dewatering by decomposing EPS. • The oxides generated by persulfate help to control the environmental risk of WAS. • The knowledge gaps and prospects based on persulfate are identified and discussed. Persulfate is considered as a promising oxidant, thus the improvement of waste activated sludge (WAS) treatment with persulfate was widely regarded as a promising technology and had been intensively investigated in recent years. However, doubts and debates about its technical and economic viability in full-scale scenarios have been raised. Interestingly, so far, no efforts have been made on either systematic summarization or critical thinking of the application of persulfate to improve WAS treatment. Therefore, it is time to assess whether and how to utilize persulfate in future WAS treatment. The present paper provided an extensive review of the mechanisms, potentials and application of persulfate in WAS treatment. The current understanding of the activation modes and mechanisms of persulfate in sludge treatment were described. Besides, the performance, mechanism and disadvantages of persulfate-based pretreatment in fermentation, digestion and dewatering process were discussed, and the role of persulfate on the removal and control of the toxicity in sludge was paid special attention. The results showed that the oxidant and interaction with microorganisms of persulfate played an important role in improving sludge treatment. Knowledge gaps and current limitations of the persulfate-based applications were identified, and perspectives on the development of persulfate-based applications were discussed. Persulfate-based technology has a great potential in improving WAS treatment, but the practical application of this technology still needs further development and larger scale demonstration. Overall, this review provided a comprehensive current understanding, future directions, and insights into issues related to the application of persulfate to improve WAS. [ABSTRACT FROM AUTHOR]

• The pore structure of sandstone under freeze-thaw was investigated by MIP test and quantified by a tri-modal exponential function. • The evolution of the characteristic pore radii corresponding to nanopores, micropores and macropores and their volumetric fractions under freeze-thaw were obtained. • The relationship between the change of fractal dimension and strength loss under freeze-thaw was built. • Growth of macropores was found to be responsible for the freeze-thaw damage of sandstones. • The microscopic and macroscopic freeze-thaw damage mechanism of the sandstones were comprehensively revealed. Although the strength loss of natural stone materials was widely investigated in the previous decades, the change law of pore structure characteristic and their correction with the strength loss under freeze-thaw was not completely understood. In this study, the pore structure change of red sandstone under freeze-thaw was continuously monitored by MIP (mercury intrusion porosimetry). The pore size distribution was characterized by a developed tri-modal exponential function. The characteristic pore radii in this function corresponding to nanopores (d < 0.05 μm), micropores (0.05 μm < d < 100 μm) and macropores (100 μm < d < 1000 μm) increased with increasing freeze-thaw cycles. However, the volumetric fractions of nanopores and micropores reduced, because some of them had developed into macropores under freeze-thaw. Fractal dimension was a good indicator to characterize the complex of pore structure, which had an obvious reduction trend against the freeze-thaw number. It illustrated that the distribution of pore size turned to be uniform, and the complexity of the pore structure decreased after repeated freeze-thaw cycles. Triaxial compression strengths of sandstones after different freeze-thaw cycles were measured. The UCS and TCS decreased due to the growth of macropores, but the confined pressure had an inhibitory effect on the freeze-thaw damage. In addition, the cohesion of sandstones decreased while the internal friction angle increased with increasing the freeze-thaw number. At last, the relationship between the mechanical strength loss and fractal dimension change was built. By analysis of the microscopic pore structure evolution and macroscopic strength loss, it can be concluded that the growth of macropores may play a dominant role in the freeze-thaw damage and strength loss. This study provides a better understanding of the macro-micro freeze-thaw damage mechanism of stone materials. [ABSTRACT FROM AUTHOR]

CircRNAs participates in the development and occurrence of multiple tumor types. However, the specific effects and underlying mechanisms of circRNA in intrahepatic cholangiocarcinoma (ICC) progression and recurrence remain poorly understood. CircRNA sequencing was performed to screen circRNAs related to ICC recurrence after surgery using 53 ICC frozen tumor specimens. We found that compared with patients who experienced postsurgical recurrence, circFOXP1 had high expression in tumor tissues from patients with no postoperative recurrence. Functional experiments revealed that circFOXP1 inhibited ICC progression in vitro and in vivo. We then found that circFOXP1 inhibited ICC progression via encoding a novel protein, circFOXP1-231aa. Mechanistically, circFOXP1-231aa directly interacted with OTUD4, which regulates NCOA4 protein stability via deubiquitination modification, and thereby enhances ferroptosis of ICC cells. Examination of clinical ICC samples found positive correlations between circFOXP1 expression levels and levels of OTUD4 and NCOA4. These three factors are predictors of prognosis in patients with ICC. Collectively, we identified circFOXP1 encoded circFOXP1-231aa, which interacted with OTUD4 to suppress ubiquitination of NCOA4 and, thereby, promoted ferroptosis and inhibited ICC recurrence. • CircFOXP1 is up-regulated in ICC patients without postoperative recurrence and predicts good prognosis. • CircFOXP1 inhibits ICC progression through encoding circFOXP1-231aa. • CircFOXP1-231aa binds with OTUD4, to enhance ICC cell ferroptosis and inhibits ICC progression. • OTUD4 promotes ICC cell ferroptosis through inhibition of NCOA4 ubiquitination. [ABSTRACT FROM AUTHOR]

Cellulose-based humidity sensors have attracted great research interest due to their hydrophilicity, biodegradability, and low cost. However, they still suffer from relatively low humidity sensitivity. Due to the presence of negatively charged carboxylate groups, 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose nanofibril (CNF) exhibits enhanced hydrophilicity and ion conductivity, which is considered a promising candidate for humidity sensing. In this work, we developed a facile strategy to improve the humidity sensitivity of CNF films by regulating their surface charge density. With the increase in surface charge density, both water uptake and charge carrier densities of the CNF films can be improved, enabling a humidity sensitivity of up to 44.5 % (%RH)−1, higher than that of most polymer-based humidity sensors reported in the literature. Meanwhile, the sensor also showed good linearity (R2 = 0.998) over the 15–75 % RH at 1 kHz. With these features, the CNF film was further demonstrated for applications in noncontact sensing, such as human respiration, moisture on fingertips, and water leakage, indicating the great potential of CNF film in humidity monitoring. A simple strategy for enhancing the humidity sensing performance of TEMPO-oxidized CNF film is proposed through the surface charge density modulation. The high surface charge density (1.45 mmol g−1) of CNF endows the sensor with increased water uptake and charge carrier densities, thus leading to improved humidity sensing performance. [Display omitted] [ABSTRACT FROM AUTHOR]

Cellulose nanofibrils (CNF) isolation based on a catalyst-free maleic anhydride esterification has proven to be effective, however, the effects of pulp hornification on CNF isolation by this strategy have yet to be explored, which could present significant impacts for CNF isolation. Herein, dried northern bleached softwood Kraft pulp (D-NBSK) and never-dried northern bleached softwood Kraft pulp (ND-NBSK) were selected as the substrates. After esterification with maleic anhydride (MA), the esterified ND-NBSK pulp (E-ND) shows a significantly smaller size and more fragmented structure than the esterified D-NBSK pulp (E-D). Meanwhile, higher degree of esterification can be realized for the never dried pulp as compared to the dried pulp, which is corroborated by the significantly stronger characteristic peaks of C O (1720 cm−1) and -COO− (1575 cm−1) from the FTIR spectra and the higher surface charge content (0.86 ± 0.04 mmol/g vs. 0.55 ± 0.05 mmol/g). A comparison of the characteristics of the resulting CNF similarly demonstrated the negative impact of hornification. Overall, this work indicates that hornification tends to reduce the accessibility of chemical reagents to the pulp, leading to insufficient deconstruction. Such negative impact of hornification should be considered when performing nanocellulose isolation, especially when using pulp as feedstock. [Display omitted] [ABSTRACT FROM AUTHOR]

• The DFT method was applied to optimize the preparation of DMIPs. • The properly DMIPs for the selective adsorption of geosmin were obtained. • The distribution ratios and imprinting factors of DMIPs were analyzed. Dummy molecularly imprinted polymers (DMIPs) were prepared by combining the molecular imprinting technique with computer simulation for the selective adsorption of geosmin (GSM). The most stable geometric configuration and single-point energy calculations of the molecules were determined by the density functional theory (DFT) method at the M06–2X/6–31 + G (d, p) and the M06–2X/def2-TZVP level, respectively. Meanwhile, the binding energy at different monomer ratios (1:1, 1:2, 1:3 and 1:4) between dummy template with monomer was calculated. According to the theoretical studies, DMIPs materials were synthesized using methacrylic acid (MAA) as the functional monomer, forming a stable molecular/monomer complex in a 1:3 ratio. The DMIPs were characterized using infrared spectroscopy, scanning electron microscopy, and thermogravimetric analysis. The theoretical adsorption capacity (Q max) of the obtained DMIPs was 1.23 mg g −1, it was approximately twice that of non-imprinted polymers (NIPs). Additionally, the results of the kinetic experiments showed that the DMIPs achieved adsorption equilibrium within 90 min. The combination of computational simulation and experimental approach can shorten the preparation cycle of DMIPs and improve their performance, enabling its efficient application in the analysis of actual samples. [Display omitted] [ABSTRACT FROM AUTHOR]

• A three-dimensional electrode system was constructed. • FMBC acts as a third electrode in the electrochemical system. • Three-dimensional system promotes organic matter leaching and methane production. Electrochemical pretreatment (EPT) of sewage sludge demonstrates an aggressive effect on extracellular polymeric substance destruction and sludge solubilization. While the low efficiency of methane production does not match the initial dissolution of the sludge after EPT. Here we proposed a novel method, using Fe-Mn-modified biochar (FMBC) strengthening electrochemical pretreatment, aiming at improving the methanogenic efficiency. The strengthening mechanism of FMBC was studied according to the physicochemical parameters of sludge at different concentrations and the change of microbial community. Experimentally, with the addition of 2 g/L FMBC, the methane production increased by 7.96% and 10.06% compared with electrochemical pretreatment alone and the control group. The sludge organic matter solubilization varied from 344.6 mg/L in E0 to 383.4 mg/L in E2 after pretreatment. Simultaneously, analysis of microbial communities showed that the addition of 2 g/L FMBC obviously increased the relative abundance of Methanofastidiosum and Methanosaeta from 5.5% and 20.9% in CK to 16% and 28.7% in E2, respectively. The addition of FMBC also intensified the acetoclastic methanogenesis and methylotrophic methanogenesis. This study provides new ideas for the enhancement of electrochemical pretreatment of sludge. [ABSTRACT FROM AUTHOR]

• Polyamide mitigated the inhibitory effect of ofloxacin on anaerobic digestion. • The presence of polyamides facilitated the degradation of ofloxacin. • Coexistence of polyamide favored the enrichment of hydrolytic acidifying bacteria. • Both glycolysis and amino acid metabolism were inhibited under ofloxacin stress. Microplastics and antibiotics are emerging pollutants that inevitably enter the sludge anaerobic digestion system. Current studies mainly focused on the individual effects of microplastics or antibiotics on methane generation. However, there may also be complex reactions between them and their combine effects on anaerobic digestion remain unclear. This study revealed the combined influencing mechanism of polyamide and ofloxacin through batch and semi-continuous tests. Brief exposure to ofloxacin was detrimental to methane production. The coexistence of polyamide enabled partial adsorption of ofloxacin, which effectively mitigates the inhibitory effect of ofloxacin at low concentrations. Polyamide also facilitated the colonization of hydrolytic bacteria and acidogens, such as Hydrogenispora , and promoted the conversion of organic matter to acetate. However, polyamide could not effectively alleviate the inhibitory effect of excess ofloxacin on anaerobic digestion. Ofloxacin at high concentrations stimulated the release of humic acid, reduced methane production by more than 80%, and changed the predominant methanogenesis pathway from acetoclastic methanogenesis to hydrogenotrophic methanogenesis. Acidogenesis and methanogenesis pathways were restructured to further explore the effect of ofloxacin on the metabolic potentials of microorganisms. Metagenomic analysis revealed that most of functional genes associated with glycolysis, amino acid metabolism and methanogenesis were down regulated under long-term stress of high concentration of ofloxacin. This study elucidated the microbial process of organic matter conversion inhibition by ofloxacin, shed light on the combined effects of polyamide and ofloxacin on anaerobic digestion and provided new insights for assessing the impact of multiple pollutants on the safe disposal of sludge. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are substrates available for biofilms colonization in natural water environments. The biofilms formation may enhance the ability of MPs to adsorb harmful contaminants. Herein, we investigated the biofilms formation of three different MPs (PVC, PA and HDPE) in simulated natural environment, and observed the chemical structure, charge property, hydrophobicity and other properties of MPs affect microbial biomass and community composition. More importantly, potential pathogens were found in all three MPs biofilms. Furthermore, the adsorption capacities of original MPs and biological aging MPs for norfloxacin (NOR) was compared. HDPE has the largest adsorption capacity for NOR, while PA has the smallest adsorption capacity for NOR. It was concluded that the formation of biofilms enhanced the adsorption of NOR by 50.60 %, 24.17 % and 46.02 % for PVC, PA and HDPE, respectively. In addition, hydrogen-bond interaction, electrostatic interaction and hydrophobic interaction were found to dominate the adsorption of NOR by MPs. Our study contributed to improve the understanding of the interactions between aging MPs and contaminants in the natural water environments, and provided essential information for ecological risk assessment of MPs. [Display omitted] • Biological senescence of different MPs under same culture conditions was compared. • The community characteristics of MPs biofilms were studied. • The attachment of biofilms increased the adsorption capacity of MPs to NOR. • Different MPs adsorption mechanisms were explored. [ABSTRACT FROM AUTHOR]

[Display omitted] • Facile, scalable production of hyperbranched wood fiber using mild disc milling. • Air dried foam assembled from hyperbranched wood fiber with no binder use. • Sub-fibrous structures of wood fiber improved foam's mechanical properties. • Natural, high melting point wax allowed enhanced water/moisture repellency. • Woody foam demonstrated better thermal insulation than commercial glass fiber mat. Demand for sustainable building thermal regulation is driving the development of low carbon-intensive, renewable, and safe-to-use materials to substitute the dominant synthetic polymers and inorganic mats. This study proposes a novel mild mechanical pretreatment strategy to fabricate high-performance, self-strengthening thermal insulation board in a low cost and scalable approach from chemi-thermomechanical pulp (CTMP), a type of high-yield wood pulp. CTMP fibers, after subject to a short period of disc milling, were found to gain abundant sub-fibrous structures at multiple scales. After foaming and air-drying, such micro-fibrillated fibers (MF-CTMP) formed robust, binder-free foam under capillary force with remarkedly stronger physical entanglement between fibers compared to that of pristine CTMP, achieving 3.7 folds Young's modulus, 2.9 folds ultimate stress, and 1.9 folds toughness with respect to the latter. Palm wax coating further provided a sustainable hydrophobic protection for the foam (contact angle of ∼ 110°). The high porosity and structural tortuosity endowed the hydrophobic MF-CTMP foam with excellent thermal insulation property (thermal conductivity of 33.1 ± 2.3 mW/(m∙K)), demonstrating significantly better performance than a commercial glass fiber thermal insulator. Compared to other lignocellulosic boards prepared using freeze-drying or supercritical drying operations, the hydrophobic MF-CTMP foam represents a novel low cost, binder-free, and scalable technology for commercial sustainable thermal insulation applications. [ABSTRACT FROM AUTHOR]

Application of phase change materials (PCM)-containing composite represents a promising passive thermal control strategy to provide indoor thermal comfort without using powered equipment. Yet, the trade-off between high thermal storage density and good thermal stability is the major obstacle that restricts the thermal regulation performance of the current PCM-containing products. This study proposed a facile approach to prepare PCM/cellulose nanofibrils (CNF) ink for 3D printed composite monolith, with very high PCM loading, good thermal stability, and robust mechanical properties. By incorporating a small amount of CNF gel as the stabilizer and viscosity modifier, the CNF-microencapsulated paraffin (model PCM) obtained essential printability to construct tailorable structure using Direct Ink Writing technology. After ice templating and freeze drying, the microencapsulated PCM particles were in-situ embedded in a CNF-assembled scaffold, forming a PCM/CNF composite. The lightweight nature of such scaffold (35.0 mg/cm3 for pure CNF matrix) endowed the composite monolith with high PCM loading (up to 82% with respect to the composite) and high thermal storage capacity (up to 153 J/g). Due to the 3D-interlinked CNF matrix and the coated CNF on PCM particles, the composite monolith not only exhibited high Young's modulus of up to 1.14 MPa but also showed exceptional thermal stability with negligible variation in microscopic morphology and thermal storage capacity, after high temperature conditioning at 80 °C for 30 h. [Display omitted] [ABSTRACT FROM AUTHOR]

• The presence of 15% lignin promoted the SCFAs production to 1.7 times from WAS, and the proportion of acetic increased by 61.8%. • Lignin was beneficial to the solubilization process, which may be related to its hydrophobic properties. • Lignin enhanced the SCFAs production bio-processes and inhibited the SCFAs consumption bio-processes. • The abundance of microorganisms related to acid production in fermenter with lignin increased. Lignin, a biological resource with great potential, can be as high as ∼16% of the total organics in the waste activated sludge (WAS). This work therefore aims to fill the knowledge gap about the effect of lignin on short-chain fatty acids (SCFAs) production from anaerobic fermentation of sludge. Experimental results showed that lignin promoted rather than inhibited SCFAs production. Specifically, the presence of 15% lignin promoted the SCFAs production from 129.1 ± 6.5 to 223.14 ± 7.8 mg COD/g VSS compared with the control, and the proportion of acetic increased by 61.8%, while that of propionic decreased by 44.9%. Mechanism exploration revealed that lignin improved the solubilization of biodegradable substrates due to its hydrophobic characteristics. In addition, lignin enhanced the acidogenesis process, possibly by perfecting the electron transfer chain in the fermentation system, and the quinone structure in lignin may compete electrons with methanogens to inhibit the consumption of SCFAs. Microbiological analysis showed that the abundance of microorganisms related to acidogenesi, especially the acetogenesis, including Proteiniclasticum sp., Acetoanaerobium sp., in the fermenter with lignin increased, which caused the community to shift towards specialized and diverse SCFAs production. [Display omitted] [ABSTRACT FROM AUTHOR]

Moisture-driven actuators featuring programmable stimuli-responsiveness and a rapid response have garnered substantial research attention. Cellulose-based actuators face challenges, including prolonged and unstable responsiveness, along with inadequate interfacial bonding. Herein, we developed a bilayer structured moisture actuator by integrating multiscale cellulose fibers with chitosan. The protonated chitosan forms strong electrostatic attractions with negatively charged cellulose nanofibrils (CNF), achieving a robust interfacial interaction. Leveraging the hierarchically porous structure and varying hygroscopicity of microfibrillated cellulose (MFC) and CNF, the film establishes an effective wettability gradient, enabling a stable and rapid moisture actuation performance. The bilayer film exhibits large deformation toward moisture with a bending angle of 60°, a short response time of 12 s, good stability over 50 wetting and drying cycles, and promising recyclability. Harnessing these advantageous properties, the bilayer film was demonstrated for its applications in automatic cooling textiles, contactless electrical switches, and artificial moisture-activated muscles, showing great potential for practical use.

Microplastics (MPs) are of particular concern due to their ubiquitous occurrence and propensity to interact and concentrate various waterborne contaminants from aqueous surroundings. Studies on the interaction and joint toxicity of MPs on engineered nanoparticles (ENPs) are exhaustive, but limited research on the effect of MPs on the properties of ENPs in multi-solute systems. Here, the effect of MPs on adsorption ability of ENPs to antibiotics was investigated for the first time. The results demonstrated that MPs enhanced the adsorption affinity of ENPs to antibiotics and MPs before and after aging showed different effects on ENPs. Aged polyamide prevented aggregation of ZnONPs by introducing negative charges, whereas virgin polyamide affected ZnONPs with the help of electrostatic attraction. FT-IR and XPS analyses were used to probe the physicochemical interactions between ENPs and MPs. The results showed no chemical interaction and electrostatic interaction was the dominant force between them. Furthermore, the adsorption rate of antibiotics positively correlated with pH and humic acid but exhibited a negative correlation with ionic strength. Our study highlights that ENPs are highly capable of accumulating and transporting antibiotics in the presence of MPs, which could result in a widespread distribution of antibiotics and an expansion of their environmental risks and toxic effects on biota. It also improves our understanding of the mutual interaction of various co-existing contaminants in aqueous environments., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)