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Type I main‐chain polyrotaxanes (PRs) with multiple wheels threaded onto the axle are widely employed to design slide‐ring materials. However, Type II main‐chain PRs with axles threading into the macrocycles on the polymer backbones have rarely been studied, although they feature special topological structures and dynamic characteristics. Herein, we report the design and preparation of Type II main‐chain PR‐based mechanically interlocked networks (PRMINs), based on which the relationship between microscopic motion of mechanical bonds on the PRs and macroscopic mechanical performance of materials has been revealed. The representative PRMIN‐2 exhibits a robust feature in tensile tests with high stretchability (1680 %) and toughness (47.5 MJ/m3). Moreover, it also has good puncture performance with puncture energy of 22.0 mJ. Detailed rheological measurements and coarse‐grained molecular dynamics (CGMD) simulation reveal that the embedded multiple [2]rotaxane mechanical bonds on the PR backbones of PRMINs could undergo a synergistic long‐range sliding motion under external force, with the introduction of collective dangling chains into the network. As a result, the synchronized motions of coherent PR chains can be readily activated to accommodate network deformation and efficiently dissipate energy, thereby leading to enhanced mechanical performances of PRMINs. [ABSTRACT FROM AUTHOR]

Polyrotaxanes (PRs) have attracted significant research attention due to their unique topological structures and high degrees of conformational freedom. Herein, we take advantage of an oligo[2]rotaxane to construct a novel class of dynamically cross‐linked rotaxane network (DCRN) mediated by metal‐coordination. The oligo[2]rotaxane skeleton offers several distinct advantages: In addition to retaining the merits of traditional polymer backbones, the ordered intramolecular motion of the [2]rotaxane motifs introduced dangling chains into the network, thereby enhancing the stretchability of the DCRN. Additionally, the dissociation of host–guest recognition and subsequent sliding motion, along with the breakage of metal‐coordination interactions, represented an integrated energy dissipation pathway to enhance mechanical properties. Moreover, the resulting DCRN demonstrated responsiveness to multiple stimuli and displayed exceptional self‐healing capabilities in a gel state. Upon exposure to PPh3, which induced network deconstruction by breaking the coordinated cross‐linking points, the oligo[2]rotaxane could be recovered, showcasing good recyclability. These findings demonstrate the untapped potential of the oligo[2]rotaxane as a polymer skeleton to develop DCRN and open the door to extend their advanced applications in intelligent mechanically interlocked materials. [ABSTRACT FROM AUTHOR]

Amidst the transition from agriculture to tourism, ethnic villages are facing issues of "misalignment" and "disequilibrium" between economic growth and cultural heritage conservation. Previous research has often isolated the effects of cultural heritage conservation or socio-economic development, neglecting their reciprocal influences within the coupling coordination. This study addresses this gap by assessing 43 villages in Leishan County, quantifying the preservation status of the cultural landscape (PSCL) and socio-economic level (SEL) using a comprehensive evaluation model and revealing the coupling coordination relationship between PSCL and SEL in each village with the coupling coordination degree (CCD) model. Spatial autocorrelation and the geographical detector model reveal the spatial agglomeration characteristics and influential factors of the CCD. The results highlight three findings. (1) The majority of villages (93%) are in a moderate imbalance stage or a serious imbalance stage, underscoring an urgent need for targeted policies. (2) Spatial autocorrelation analysis exposes significant clustering, with the northwest corner exhibiting the most pronounced high-value aggregation, which contrasts with the southern region's low-value clustering. A 'low–high' clustering pattern is observed in the northern region, while the southwestern corner presents a 'high–low' distribution. (3) Key determinants affecting the CCD include the tourism revenue, tourist volume, resident participation in tourism, village hollowing level, and number of historical buildings. The interactions between driving factors show non-linear and two-factor enhancement effects. This study concludes with policy recommendations advocating for context-specific strategies to enhance the CCD, emphasizing the importance of aligning cultural preservation with economic progress in ethnic villages. [ABSTRACT FROM AUTHOR]

The cold recycling technology of asphalt pavement has great economic benefits, is friendly to the environment and has a good development prospect. But the reclaimed asphalt pavement (RAP) is used as the "black aggregate," and the aged asphalt has not been fully utilized. Therefore, activating and reusing the aged asphalt in RAP is one of the key problems to be solved. By using artificially aged asphalt instead of naturally aged asphalt, this work reports a new technique for activating asphalt of RAP by functional oil emulsion. The functional oil emulsion was prepared by phase inversion method, and the asphalt regeneration effects were studied in detail. The optimum results showed that the solid content of the functional oil emulsion was 50% and the average particle size was 2.17 μm. The storage stability of 1 day and 5 days were 2.2% and 4.8% respectively, and the demulsification time at 20 °C and 40 °C were 2 hours and 1 hour respectively. By studying the penetration, ductility and softening point of recycled asphalt under different dosages of functional oil emulsion, it is found that the parameters of the recycled asphalt recover to more than 94% at 12% content of functional oil emulsion. [ABSTRACT FROM AUTHOR]

In this study, removal of Cd from aqueous media by the adsorption of TiO2 nanoparticles (TNPs), with surface modification by humic acid (HA) was assessed. Results showed a linear increase of the coating percentage from 100–HA to 250–HA but no significant difference between the HA coated TNPs prepared at 250 and 350 mg L–1 due to an extremely narrow band gap. The obtained materials (HA–TNPs) were characterized by Fourier transform infrared spectroscopy and UV–visible spectrophotometer. Then, batch adsorption techniques were carried out to examine the possible adsorption mechanisms of Cd onto TNPs and HA–TNPs. It was noted that the adsorption capacity of the HA– TNPs for Cd enhanced considerably as compared to that of the bare TNPs, implying that HA coating might modify bioavailability of Cd in aquatic environment. Equilibrium data were best described by the Freundlich equation, and the partition distribution coefficient (k) of HA–TNPs increased by 34%, 50% and 59% for Cd at 298, 315 and 332 K respectively, as compared to the bare TNPs, suggesting that HA–TNPs had a stronger affinity of sites for Cd adsorption than that of bare TNPs. [ABSTRACT FROM AUTHOR]