Search

This paper explores the challenges and opportunities presented by the digitization and intelligent clustering in the mining industry, focusing on the security and inter-system influences within Cyber-Physical Systems (CPS) of smart mining clusters. Utilizing the NK model and complex adaptive systems theory, we construct a dual-layered network and cascade failure model, alongside a dynamic repair strategy that adapts to environmental changes. By analyzing the critical parameters of node number (N) and relationship density (K), we assess the resilience of smart mining CPS under cascade failures with dynamic repairs. Our findings reveal that dynamic repair strategies significantly enhance network resilience against both random and deliberate attacks, with N and K acting as crucial regulators of repair effectiveness. This suggests that adapting N and K can improve repair outcomes and system resilience, despite increasing complexity. The paper discusses the practical implications of these strategies through simulation and real-world scenarios, highlighting the need for adaptive repair strategies in enhancing smart mining CPS resilience and process safety. Introducing the NK model to CPS resilience research offers new insights into the resilience of smart mining cyber-physical systems and provides a comprehensive risk analysis method for these systems in complex scenarios.

Polymer–substrate interfaces can alter the dynamics of a confined polymer film. However, the influence of interfacial interactions on chain dynamics is unclear owing to difficulty in measurement. Herein, the effects of substrate–polymer interactions on the chain relaxation dynamics of confined-entangled polystyrene (PS) thin films were investigated. The chain relaxation time of a PS film on substrates with interfacial energies (γs–p) of 44.9 and 2.3 mJ m–2monotonically decreased and increased, respectively, with a decrease in film thickness. The chain relaxation time of the PS film on substrates with γs–pranging from 33.5 to 10.6 mJ m–2decreased and then increased with decreasing film thickness, and this trend become monotonically increasing with the decrease of γs–p. A new model describing this particular relaxation behavior is proposed and was used to elucidate the origin of the nonmonotonic chain relaxation dynamics of PS chains, which is attributed to the competition between disentanglement and substrate effects. The former accelerates while the latter retards the chain relaxation dynamics of the PS films. The impact of the PS free surface on relaxation dynamics decreases rapidly with the decrease of γs–p. This phenomenon was further confirmed via Monte Carlo simulations. These results provide a new perspective for elucidating the mechanism of interface interactions affecting chain relaxation in the confined polymer film.

Understanding the response of vegetation variation to climate change and human activities is critical for addressing future conflicts between humans and the environment, and maintaining ecosystem stability. Here, we aimed to identify the determining factors of vegetation variation and explore the sensitivity of vegetation to temperature (SVT) and the sensitivity of vegetation to precipitation (SVP) in the Shiyang River Basin (SYRB) of China during 2001–2022. The climate data from climatic research unit (CRU), vegetation index data from Moderate Resolution Imaging Spectroradiometer (MODIS), and land use data from Landsat images were used to analyze the spatial-temporal changes in vegetation indices, climate, and land use in the SYRB and its sub-basins (i.e., upstream, midstream, and downstream basins) during 2001–2022. Linear regression analysis and correlation analysis were used to explore the SVT and SVP, revealing the driving factors of vegetation variation. Significant increasing trends (P<0.05) were detected for the enhanced vegetation index (EVI) and normalized difference vegetation index (NDVI) in the SYRB during 2001–2022, with most regions (84%) experiencing significant variation in vegetation, and land use change was determined as the dominant factor of vegetation variation. Non-significant decreasing trends were detected in the SVT and SVP of the SYRB during 2001–2022. There were spatial differences in vegetation variation, SVT, and SVP. Although NDVI and EVI exhibited increasing trends in the upstream, midstream, and downstream basins, the change slope in the downstream basin was lower than those in the upstream and midstream basins, the SVT in the upstream basin was higher than those in the midstream and downstream basins, and the SVP in the downstream basin was lower than those in the upstream and midstream basins. Temperature and precipitation changes controlled vegetation variation in the upstream and midstream basins while human activities (land use change) dominated vegetation variation in the downstream basin. We concluded that there is a spatial heterogeneity in the response of vegetation variation to climate change and human activities across different sub-basins of the SYRB. These findings can enhance our understanding of the relationship among vegetation variation, climate change, and human activities, and provide a reference for addressing future conflicts between humans and the environment in the arid inland river basins.

To explore the substrate effect on chain conformation, sum frequency generation vibrational spectroscopy was used to investigate the variation in the surface structure of a supported poly(methyl methacrylate) film with different thicknesses of the polymer film (h) and adsorbed layer (hads). The average local chain conformation at the surface was employed as a phenomenological marker and described by a chain arc model. With the decreasing of h, the surface conformation approached from the unperturbed surface conformation to that of adsorbed chains, which indicated the existence of a conformation gradient near the substrate. It was also found that the distance of chain conformation perturbed by the substrate effect was dependent on the formation of an irreversible adsorption layer and increased linearly with hads. This linear dependence is consistent with the correlation between the propagation distance of the substrate effect on chain mobility and hads; therefore, the conformation gradient may be the probable origin of the long-range substrate effect.

Co-Ru-based compounds were successfully synthesized on nitrogen-doped two-dimensional carbon nanosheets by a one-step pyrolysis process. The obtained catalyst has excellent HER, OER, and ORR properties.

This work describes a Lewis-acid-coordination strategy to efficiently enhance the electrophilicity of a carbene beyond structural modification. A hybrid BCF–DAC is formed by the coordination of a Lewis acid, B(C6F5)3(BCF), to an N,N′-diamidocarbene (DAC), possessing superior low LUMO energy that is indicated by theoretical calculation. This endows the hybridized carbene with a unique reactivity that speeds up the activation of the sp3-hybridized C–H bond of toluene and the [2+1] cycloaddition with C2H2. More strikingly, the hybrid readily undergoes [2+1] cycloaddition with C2H4under ambient conditions, which is the first example of a stable carbene reacting with ethylene. The Lewis acid approach also features dynamic behavior and electrophilicity tunability.

Polyradicals, i.e., multispin organic molecules, are playing important roles in radical-based material applications for their spin–spin interaction. A dynamic covalently bonded multispin molecule may endow materials with added function such as memory and switching. However, such a species has yet to be reported. We here report the synthesis, characterization, and crystal structure of a dynamic triradical species. It is generated by the self-assembly of two molecules through a Lewis acid coupled electron transfer. The crystalline species is spin-frustrated without Jahn–Teller distortion at low temperature, while it dissociates back to diamagnetic starting material in solution at high temperature. The reversible process is tracked by variable-temperature NMR, EPR, and UV–vis–NIR spectroscopy. Isolation, property study, and dynamic bonding investigation on such a species lay the foundation for the design of functional polyradicals with potential application as memory or switching devices.

Deviations of chain conformations from Gaussian statistics induce entropic stress that affects the dynamics of polymer materials. Understanding its role is further complicated by the presence of enthalpic stresses, arising from the concurring change in bond energy and intermolecular interactions. By fabricating oriented poly(methyl methacrylate) brushes free from backbone deformation, we successfully identified the role of entropic stress on the nonisothermal relaxation of chains at both global and local levels. We show that the entropic stress unjams the local backbones and is responsible for the occurrence of a stress-sensitive glassy state near Tg, where the local backbone motion provokes chain contraction upon heating. Remarkably, the intrachain stress does not affect local secondary relaxations involving side-group rotation nor thermal expansion in the deep glassy state. These results cast light on the dynamics and fundamental molecular mechanics of oriented, stressful polymer glasses, such as textile fibers.

In a previous experiment, we observed that the glass transition temperature of the surface monolayer glass transition temperature (Tgsurf) of unannealed polystyrene (PS) films spin-coated on oxide-coated silicon decreased with decreasing film thickness (h< ∼60 nm). However, this hdependence could be removed by thermal preannealing. In this experiment, we investigated the origin of this preannealing effect. We found that Tgsurfof the thin films increased with preannealing time (tANN) and reached the steady-state thick-film value at a characteristic time (τsurf) following the τsurf∼ h2scaling for diffusion. Moreover, chain adsorption occurred alongside the increase in Tgsurfduring thermal preannealing and reached the steady-state adsorbed amount at a time similar to τsurf. We tentatively suggest that the observed increase in Tgsurfwith tANNwas caused by diffusion of free-volume holes from the polymer–substrate interface to the free surface due to densification of the interfacial polymer upon chain adsorption.

This paper is concerned with the problem of input-output finite-time guaranteed cost control for a kind of time-varying systems (TVSs). To reduce the transmission burden, an aperiodic-sampling-based event-triggered mechanism is proposed with an adaptive law. And a time-varying Lyapunov functional involving some time-dependent piecewise matrices is designed. Input-output finite-time stability (IO-FTS) conditions are presented for the closed-loop system. By resorting to properties of the matrix polynomial, input-output finite-time stabilization criterions are further derived by recursive linear matrix inequalities. And the sampled-data static output feedback controller can be obtained. In addition, the corresponding optimization problem about minimum values of both the guaranteed cost bound and system output norm are established. Finally, a spring-mass-damper system illustrates the effectiveness and superiority

ABSTRACTAt present, people use a large amount of coal, oil and other energy while causing a series of environmental pollution problems. In response to the national 3060 policy, improving the utilization of solar energy is imminent. Solar photovoltaic air collector can not only collect heat efficiently but also reduce the surface temperature of solar cells to improve the photoelectric conversion efficiency. The research progress of solar photovoltaic air collector system improvement and application scenarios are reviewed. The theoretical and experimental research of solar photovoltaic air collector in improving photoelectric/photothermal conversion efficiency is analyzed, the current application scenarios and advantages of solar photovoltaic air collector are discussed, and the research direction of solar photovoltaic air collector is prospected.

Oil spills interact with mineral particles to form oil–particle aggregates (OPAs), which promotes the oil’s natural diffusion and biodegradation. We investigated the effect of bacteria on the formation and vertical migration of OPAs under different concentrations and types of particles and proposed and elucidated an oil–particle–bacteria coupling mechanism. The depth of particle penetration into oil droplets (13–17 μm) was more than twice that of the nonbacterial group. Oil that remained in the water column and deposited to the bottom decreased from 87% to 49% and increased from 14% to 15% at high/low concentration, respectively. Interestingly, the median droplet diameter showed a negative correlation (R2= 0.83) and positive correlation (R2= 0.60) at high/low concentration, respectively, with the relative penetration depth first proposed. We further demonstrated that bacteria increased the penetrating depth by a combination of reducing/increasing the interfacial tension, reducing the oil amount (C17–C38) in the OPAs, and increasing the particle width. These effects reduced the droplet size and ultimately changed the vertical migration of OPAs. Finally, we provided a simple assessment of the vertical distribution of OPAs in nearshore environments based on experimental data and suggested that the role of bacteria in increasing the depth of particles penetrating into the oil droplets should not be ignored. These findings will broaden the research perspective of marine oil spill migration.

Objective: To understand the sociodemographic, geographical, and clinical characteristics of rural veterans utilizing home modification (HM) healthcare services under the Home Improvement Structural Alterations (HISA) program, to compare these characteristics between rural and urban veteran users, to estimate the costs of HMs performed, and to present distance that users traveled to HISA-prescribing medical facilities within the Veterans Health Administration (VHA).Background: Accessible housing is in short supply. HMs allow veterans with disabilities (VWDs) to remain living at home rather than enter institutional-type settings. HISA is associated with decreased inpatient hospitalization rates and increased use of preventative healthcare via outpatient clinic visits. Home accessibility provides psychological benefits improving social interactions and interaction with the physical environment.Methods: This retrospective database study analyzes data from the National Prosthetics Patient Database and other medical datasets within the VHA.Results: Results provide a profile of and comparison between rural and urban veteran users. HISA users are substantially older compared to younger VWDs. The frequency of bathroom, railing, and wooden ramp HMs differed significantly between rural and urban users (pvalues < .001). Rural users traveled more miles than urban users to reach a prescribing facility.Conclusions: Older adults and individuals with disabilities have unmet housing needs since accessible housing is in short supply. This HM healthcare service is helping to meet the housing accessibility needs of older veterans, VWDs, older adults, and people with disabilities, in general.

Carbon attainment and carbon neutrality are inherent requirements for promoting high-quality development, and the carbon emission efficiency of cities in the Yellow River Basin(YRB) directly affects the high-quality development of the Yellow River Basin. In this paper,we measures the carbon emission efficiency of 61 cities in the YRB from 2004 to 2018 using the super-efficiency Slack-Based Measure model (super-efficient SBM model), and explores the spatial and temporal heterogeneity and spillover effects of the new carbon emission efficiency values by combining empirical orthogonal functions and spatial autoregressive models. The results show that: (1) The spatial pattern of cities in the YRB has changed from “pretty high in the centre and low in the surroundings” to “agglomeration in high-value zones as well as dispersion in low-value zones”. (2) GDP per capita and government involvement are positively related to carbon emission efficiency, while GDP per capita squared, energy intensity and industrial structure are negatively correlated with carbon emission efficiency. (3) Reducing the proportion of fossil energy consumption, strengthening government regulation and optimising​ industrial structure are effective ways to improving the efficiency of carbon emissions in the YRB.

Developing multifunctional electrocatalysts toward energy-related reactions could reduce the cost and improve the utilization efficiency of raw materials. Herein, defective CoP decorated with ultrafine Pt nanoparticles (Pt/d-CoP/NPC) with multifunctional electrocatalytic performances is prepared viafacile pyrolysis and following chemical reduction process. The as-synthesized Pt/d-CoP/NPC owns high half-wave potential of 0.82 V for oxygen reduction reaction with excellent stability in 0.1 mol/L KOH. Density functional theory calculations demonstrate that the adsorption energy of *OO at Pt/d-CoP/NPC is stronger compared to Pt, yielding higher catalytic activity for ORR. Moreover, the resultant electrocatalyst possesses excellent catalytic activities with low overpotentials toward hydrogen evolution reaction (33 mV in 1 mol/L KOH, 6 mV in 0.5 mol/L H2SO4and 70 mV in 1 mol/L PBS) and oxygen evolution reaction (320 mV) at 10 mA/cm2. Water-splitting and rechargeable Zn-air batteries assembled with the as-synthesized Pt/d-CoP/NPC as electrodes exhibit outstanding activity and long-range stability. Remarkably, sustainable energies and homemade Zn-air battery can efficiently drive the Pt/d-CoP/NPC electrolyzer with sumless hydrogen bubbles generated, verifying the potential applications for renewable energy storage.

The adsorbed polymer layer on the inorganic solid surface is crucial in improving the physical properties of composite nanomaterials; therefore, the properties could be tuned by altering the structure of the adsorbed layer. We investigated poly(methyl methacrylate) (PMMA) adsorbed layers on SiO2–Si substrates by varying the hydroxyl (OH) group content on the substrate surface. The results indicated that the thicknesses of the flattened layer and loosely adsorbed layer decreased with decreasing OH group content and the flattened layer disappeared when the content was ∼31%. The OH groups controlled the formation of the adsorbed layer, providing anchor points through hydrogen bonding with the carbonyl groups in PMMA. With decreasing OH group content, fewer anchor points possibly prevented train conformation and the relatively stable loosely adsorbed chains still formed, which enhanced the segmental dynamics of the ultrathin PMMA film. These results provide novel insight into the role of surface chemistry in forming adsorbed polymer layers on substrates.

•MALAT1/POSTN are boosted, and related with M2 infiltration/poor prognosis in TNBC.•MALAT1 is up-regulated in TNBC-derived EVs and induces M2 polarization via EVs.•TNBC-EV-derived MALAT1 induces macrophage M2 polarization by promoting POSTN.•POSTN inhibition curbs M2 polarization by suppressing the Hippo/YAP pathway.•TNBC-EV-derived MALAT1 induces M2 polarization and facilitates TNBC development.

Confinement alters polymer dynamics and results in a marked Tgconfinement effect, i.e., a reduction in the glass-transition temperature (Tg) of a polymer under confinement. The Tgconfinement effect is related to dynamic enhancement at the air interface caused by reductions in intermolecular cohesion forces at the interface. Thus, tuning molecular interactions at the interface allows modification of the Tgconfinement effects of polymers. In this work, using interfacial-sensitive sum-frequency generation (SFG) spectroscopy, we demonstrated that incorporation of bulky and polar maleic anhydride (MA) into polystyrene (PSt) chains in an alternating manner, forming an alternating copolymer of P(St-alt-MA), led to reductions in π-π and dipolar interactions at the air interface relative to those in the bulk. This reduction in molecular interactions led to greater mobility enhancement at the interface compared with the sluggish dynamics in the bulk, and accordingly, the P(St-alt-MA) alternating copolymer experienced a distinctly greater Tgconfinement effect. These results demonstrated the impacts of local conformations and molecular interactions at the interface on the confinement effects of polymers and reinforced the idea of effective manipulation of confined polymer dynamics by changing the packing of molecules and functional groups at the interface.

The spatially heterogeneous dynamics in supported ultrathin polymer films are widely recognized to explain their unique thickness-dependent physical properties. In this paper, the surface dynamics of supported poly(ethylene terephthalate) films were scaled by the surface crystallization rate to investigate the variations of the spatially heterogeneous dynamics with various thicknesses of the film (h) and the adsorbed layer (hads). It was found that the utmost propagation distance of the substrate effect (hs), which increased with hads, is a crucial parameter affecting the surface dynamics and determining the spatial distribution of chain mobility in polymer thin films. Either decreasing hor increasing hadsto induce h< hscauses the surface dynamics to gradually change from the highest undisturbed mobility to greatly suppressed to an eventual uncrystallizable state, corresponding to the fading of the spatially heterogeneous dynamics. These observations will help us to further understand the heterogeneous chain mobility distribution in supported polymer ultrathin films.

•High METTL3 expression in non-small cell lung cancer cells correlates with increased tumor proliferation.•METTL3 regulates RIG-I-MAVS signaling pathway via m6A modifications, highlighting its critical role in tumor biology.•Mettl3-mediated methylation of DDX58, with YTHDF2 as its methylation reader protein.•Non-small cell lung cancer cells suppress RIG-I-MAVS signaling and immune responses through METTL3-mediated methylation.

Salt spray is a natural disturbance in coastal area of Southern China.Arbuscular mycorrhizal fungi can mediate the detrimental effects of salt spray.Leaf thickness and photosynthetic ability are key parameters.Combined fungi may be beneficial for trees grown in coastal areas.

When compared with pure water, hydrogen produced by seawater electrolysis has a better practical application potential. By replacing the oxygen evolution reaction (OER) and competitive chlorine evolution reaction (ClER) with the thermodynamically favorable anodic hydrazine oxidation reaction (HzOR) in alkaline seawater, energy-saving hydrogen production can be achieved. In this study, Fe/Co dual-doped Ni2P and MIL-FeCoNi heterostructures (FeCo-Ni2P@MIL-FeCoNi) arrays with simultaneous cation doping and hetero-engineering provide excellent bifunctional electrocatalytic performance for HzOR and hydrogen evolution reaction (HER) in alkaline seawater electrolyte. Overall hydrazine splitting (OHzS) in seawater is impressive, with a low cell voltage of only 400 mV required to reach 1000 mA cm−2and stable operation for 1000 h to maintain above 500 mA cm−2. As a proof-of-concept, the OHzS system can save 3.03 kW h when producing 1.0 L of H2when compared with the N2H4-free seawater system, resulting in energy-saving H2production. Density functional theory calculations show that the combination of Co-doping and the fabrication of FeCo-Ni2P and MIL-FeCoNi heterointerfaces can result in a low water dissociation barrier, optimized hydrogen adsorption free energy toward HER, and favorable adsorbed dehydrogenation kinetics for HzOR. This processing route paves the way for a practical approach to the efficient utilization of hydrogen, which is abundant in the ocean energy field, to achieve a carbon-neutral hydrogen economy.

A stable cross-conjugated diradical was prepared by the reaction of a donor–acceptor–donor (D–A–D) molecule with B(C6F5)3. Its geometry and electronic structure were characterized by single crystal X-ray diffraction, EPR spectroscopy, SQUID measurement, UV/vis spectroscopy, and DFT calculation. It has an open-shell singlet ground state with a thermally excited triplet state. It can be viewed as an intramolecular radical ion pair, and the formation mechanism is proposed as an intramolecular single electron transfer that occurs from the bis(triarylamine) donor fragment to the central dioxophenyl acceptor moiety, induced by the acidic boron atom. This work provides a Lewis acid induced approach to the formation of neutral and cross-conjugated diradicals.

The structure of water at the graphene oxide (GO)/water interface has received considerable attention due to the high performance of GO in a wide number of applications. In this work, a face-up geometry of sum frequency generation (SFG) vibrational spectroscopy was employed to deduce the structure of water at the GO/water interface in which GO nanosheets were covered onto the water surface via Langmuir compression. The SFG results showed that the intense OH stretching bands at the range of 3000–3600 cm–1were predominant in the spectrum with high GO coverage, which is mainly due to the third-order susceptibility χ(3)response from the water orientation in the electrical double layer induced by the static electric field of the negatively charged GO surface. In addition, the second-order susceptibility χ(2)response was relatively weak, suggesting that a few water molecules formed a H-bonding network within the closest GO surface. This work is beneficial to the in-depth understanding of water in contact with GO-based materials.

The North China craton is encircled by four successive triple-conjugated rifts, which are respectively the centres of large igneous provinces (LIPs) of bimodal compositions, i.e. Xiong'er rift (south, c.1.78 Ga Taihang LIP), Yanliao rift (north, c.1.32 Ga Yanliao LIP), Xuhuai rift (east, c.1.23 Ga Licheng and c.0.92 Ga Dashigou LIPs) and Langshan rift (west, c.0.82 Ga Qianlishan LIP). These rifts are genetically related to their contemporaneous LIPs based on their consistent geometry. Spatial migration of these rifts and LIPs indicates their propagation from along one marginal side to the opposite side of the craton, which may have resulted in the sequential breakup of the proto-North China craton from one side to the other during 1.8–0.8 Ga. However, the observation that the lithosphere under the LIP-associated rift regions is less destroyed (decratonized) in the Mesozoic indicates a possible role of LIPs in strengthening intracratonic steady state. This study shows that LIPs may change craton stability in either direction.

Carbynes (R–C:°), species that bear a monovalent carbon atom with three non-bonding valence electrons, are important intermediates and potentially useful in organic synthetic chemistry. However, free species of the type R–E:°of any group 14 element (E) have eluded isolation in the condensed phase due to their high reactivity. Here we report the isolation, characterization and reactivity of a crystalline germylyne radical by using a sterically hindered hydrindacene ligand. The germylyne radical bears an essentially one-coordinate germanium atom as shown by single-crystal X-ray diffraction analysis. Electron paramagnetic resonance spectroscopic studies and theoretical calculations show that the germylyne radical features a doublet ground state, and the three non-bonding valence electrons at the germanium atom contribute to the lone pair of electrons as the highest occupied molecular orbital-3 and one unpaired electron as the singly occupied molecular orbital.