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This paper focuses on the facial micro-expression (FME) generation task, which has potential application in enlarging digital FME datasets, thereby alleviating the lack of training data with labels in existing micro-expression datasets. Despite obvious progress in the image animation task, FME generation remains challenging because existing image animation methods can hardly encode subtle and short-term facial motion information. To this end, we present a facial-prior-guided FME generation framework that takes advantage of facial priors for facial motion generation. Specifically, we first estimate the geometric locations of action units (AUs) with detected facial landmarks. We further calculate an adaptive weighted prior (AWP) map, which alleviates the estimation error of AUs while efficiently capturing subtle facial motion patterns. To achieve smooth and realistic synthesis results, we use our proposed facial prior module to guide motion representation and generation modules in mainstream image animation frameworks. Extensive experiments on three benchmark datasets consistently show that our proposed facial prior module can be adopted in image animation frameworks and significantly improve their performance on micro-expression generation. Moreover, we use the generation technique to enlarge existing datasets, thereby improving the performance of general action recognition backbones on the FME recognition task. Our code is available at https://github.com/sysu19351158/FPB-FOMM. [ABSTRACT FROM AUTHOR]

Antimony contamination from textile industries has been a global environmental concern and the existing treatment technologies could not reduce Sb(V) to meet the discharge standards. To overcome this shortcoming, ferric flocs were introduced to expedite the biological process for enhanced Sb(V) removal in wastewater treatment plant (WWTP). For this purpose, a series of laboratorial-scale sequential batch reactor activated sludge processes (SBRs) were applied for Sb(V) removal with varied reactor conditions and the transformation of Fe and Sb in SBR system was investigated. Results showed a significant improvement in Sb(V) removal and the 20 mg L−1 d−1 iron ions dosage and iron loss rate was found to be only 15.2%. The influent Sb(V) concentration ranging 153–612 μg L−1 was reduced to below 50 μg L−1, and the maximum Sb(V) removal rate of the enhanced system reached about 94.3%. Furthermore, it exhibited high stability of Sb(V) removal in the face of antimonate load, Fe strike and matrix change of wastewater. Sludge total Sb determination and capacity calculation revealed decreasing in Sb adsorption capacity and desorption without fresh Fe dosage. While sludge morphology analysis demonstrated the aging and crystallization of iron hydroxides. These results verify the distinct effects of fresh iron addition and iron aging on Sb(V) removal. High-throughput gene pyrosequencing results showed that the iron addition changed microbial mechanisms and effect Fe oxidized bacterial quantity, indicating Sb(V) immobilization achieved by microbial synergistic iron oxidation. The present study successfully established a simple and efficient method for Sb(V) removal during biological treatment, and the modification of biological process by iron supplement could provide insights for real textile wastewater treatment. [Display omitted] • Ferric flocs were introduced to expedite Sb(V) removal in aerobic biological treatment system. • Moderate iron dosage into SBRs could effectively remove Sb(V), but iron aging decreased its removal rate leading to desorption. • Morphological analysis demonstrated iron hydroxides aging and crystallization. • Fresh iron supplement could effectively prevent iron aging and enhanced Sb(V) adsorption. [ABSTRACT FROM AUTHOR]

Advanced sensation and actuation abilities of various living organisms in nature have inspired researchers to design bioinspired self‐sensing soft actuators. However, the majority of conventional soft actuators primarily possess actuation capabilities while lacking a real‐time sensing signal feedback. Here, a promising strategy is reported to develop highly stretchable and conductive hydrogels for bioinspired self‐sensing soft actuators, which integrate actuation and strain‐sensing functions into a single materials system. The conductive hydrogels are designed and fabricated by in situ copolymerization of amino‐functionalized MXene‐encapsulated liquid metal nanodroplets (LM@A‐MXene) and poly(N‐isopropylacrylamide) hydrogels with controllable activated nanogels as nano‐cross‐linkers. The resulting hydrogel presents a compacted conducting network and highly porous microstructure, giving rise to robust integration of high conductivity, excellent strain sensitivity, broad stretchability, high stability, and fast response speed. Interestingly, the gradient network structure, formed by self‐precipitation of LM@A‐MXene, endows the hydrogel with shape‐programmable actuation, light‐driven remote control, and self‐sensing function. As a proof‐of‐concept application, the soft gripper based on the self‐sensing hydrogel actuators is developed, which can not only grasp, lift, and release objects, but also perceive every movement state by monitoring resistance changes. The proposed self‐sensing soft actuator can offer new insights for developing smart soft robotics and other artificial intelligent devices. [ABSTRACT FROM AUTHOR]

Developing hydrogel actuators with excellent driving performance and extended lifespan remains challenging. Ti3C2Tx MXene, as a two-dimensional nanomaterial with a unique layered structure, has attracted widespread attention in flexible hydrogel actuators for its excellent optical absorption properties and tunable surface functionality. However, MXene faces difficulties in dispersion and is prone to oxidation, which significantly hinders the development and use of MXene-based hydrogel actuators. In this study, we fabricated a near-infrared light-driven hydrogel actuator with rapid photo responsiveness and antioxidative properties by incorporating modified MXene with antioxidant characteristics and the pore-forming agent polyvinyl alcohol into the poly(N-isopropylacrylamide) (PNIPAM) hydrogel system. We functionalized MXene nanosheets with (3-aminopropyl)triethoxysilane (APTES), effectively enhancing antioxidative properties, preventing structural degradation caused by spontaneous oxidation, and improving surface properties. This enhanced the dispersion stability of MXene in the system and extended its lifespan from 7 days to over two weeks. The hydrophilic polyvinyl alcohol chains served as drainage channels during hydrogel contraction, imparting the hydrogel with rapid driving capabilities (127.1° s−1). Additionally, leveraging the fast response characteristics, we designed an octopus-inspired light-driven soft swimmer and gripper. This work provides novel insights into the application of intelligent responsive hydrogels in biomimetic and practical scenarios.Graphical abstract: Developing hydrogel actuators with excellent driving performance and extended lifespan remains challenging. Ti3C2Tx MXene, as a two-dimensional nanomaterial with a unique layered structure, has attracted widespread attention in flexible hydrogel actuators for its excellent optical absorption properties and tunable surface functionality. However, MXene faces difficulties in dispersion and is prone to oxidation, which significantly hinders the development and use of MXene-based hydrogel actuators. In this study, we fabricated a near-infrared light-driven hydrogel actuator with rapid photo responsiveness and antioxidative properties by incorporating modified MXene with antioxidant characteristics and the pore-forming agent polyvinyl alcohol into the poly(N-isopropylacrylamide) (PNIPAM) hydrogel system. We functionalized MXene nanosheets with (3-aminopropyl)triethoxysilane (APTES), effectively enhancing antioxidative properties, preventing structural degradation caused by spontaneous oxidation, and improving surface properties. This enhanced the dispersion stability of MXene in the system and extended its lifespan from 7 days to over two weeks. The hydrophilic polyvinyl alcohol chains served as drainage channels during hydrogel contraction, imparting the hydrogel with rapid driving capabilities (127.1° s−1). Additionally, leveraging the fast response characteristics, we designed an octopus-inspired light-driven soft swimmer and gripper. This work provides novel insights into the application of intelligent responsive hydrogels in biomimetic and practical scenarios. [ABSTRACT FROM AUTHOR]

• Energy performance of HVACs in super high-rise buildings were field-tested and analyzed. • The representative issues leading to large energy consumption of HVACs were summarized. • Commissioning of VAV system and multistage chilled water systems were conducted. • The setting values of HVACs should be adjusted in time according to practical cooling demand. The HVACs in super high-rise buildings commonly consists of variable air volume (VAV) systems, multistage chilled and cooling water systems, primary-secondary chilled water system in chiller plant, and the chillers combination is much more complex, leading to the significantly higher energy consumption than that of normal buildings. This paper contains field tests and comparative studies on the operation performance of HVACs in two super high-rise buildings and summarized representative issues accounting for the high energy consumption. Field test results showed that the annual energy efficiency of the whole HVAC system, before being commissioned, was only 1.79 and 2.15 in two projects. The HVACs, typically VAV systems, chilled and cooling water systems, all suffered from over-supplying and energy wasting. Besides, the chillers commonly operated with a low partial load ratio (PLR), whose energy performance was much lower than expected. Aiming to dig out the typical issues, analyses were carried out from external, internal factors, and their interconnection. Furthermore, optimization methods were put forward with corrected vital indexes. Results showed that proper control strategies should maintain the VAV system, multistage chilled and cooling water system operating with significant distribution temperature differences, tiny distribution pressure drops, and high energy efficiency, thus achieving energy saving and ensuring space cooling effects. Besides, the control strategies, especially the number control of chillers, were influential during the whole cooling season to ensure the chillers operate with optimal PLR and thus achieve better energy performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • MOFs act as dual-functional adsorbents and electrocatalysts for the removal of PPCPs. • Real active sites of MOFs are pinpointed using in-situ electrochemical methods. • Fe-MOFs exhibit high efficacy and stability in practical wastewater treatment. Pharmaceuticals and personal care products (PPCPs) pose a significant wastewater pollution concern. While electrochemical oxidation is promising, it struggles with slow mass transfer. To address this, we propose a novel strategy utilizing bifunctional metal–organic frameworks (MOFs) that couple an adsorbent with an electrocatalyst. The real active sites within iron-based MOFs responsible for the adsorption of PPCPs are MIL-101(Fe) molecules, while the in-situ formed active sites, α -FeOOH, accelerate the charge transfer under bias, contributing to the electrooxidation of PPCPs. The rapid destruction of adsorbed organics on the dual-functional electrode surface enables to release adsorption sites. This, in turn, paves the way for fast and efficient re-adsorption of PPCPs molecules, consequently promoting mass transfer. Iron-based MOFs exhibit excellent adsorption capacity (∼60 mg g−1 for sulfosalicylic acid, ∼15 mg g−1 for acetaminophen) and electrooxidation ability (94 % removal in 2 h, 31.2 kWh kg−1 COD) with good stability in realistic pharmaceutical wastewater treatment. This study offers a novel strategy for removing PPCPs using molecular electrocatalysts and provides new insights for designing and constructing MOFs for refractory wastewater treatment. [ABSTRACT FROM AUTHOR]

Radiant cooling in buildings, as an energy-saving and comfort cooling method, is very promising in creating a green and healthy indoor thermal environment in buildings. However, radiant panels are prone to dew condensation and have low cooling capacity; thus, their application in hot and humid regions is limited. Covering the surface of the radiant cooling panel with a high transmittance low conductivity material (HTLCM), and, separating the air contact surface and the radiating surface, to form a new decoupled radiant cooling technology is an effective way to address the deficient radiant cooling capacity and easy condensation. Radiation heat exchange occurs between the radiant cooling surface and the indoor heat source surface through the HTLCM, while the indoor humid air undergoes convective heat exchange with the higher temperature HTLCM surface. The optical, and thermal properties of the material determine the cooling capacity and condensation resistance (thermal performance) of the radiant cooling air conditioning. This review provides a summary of the research advances in HTLCM-assisted radiant cooling air conditioning (RCAC) in recent years. First, the classification and optical and thermal properties of the currently used HTLCMs for radiant cooling are presented. Second, the heat transfer mechanism of RCAC with HTLCM is introduced. Finally, the research advances in the application of HTLCM-assisted radiant cooling are summarized, and the challenges and future development in this field are provided. The practical engineering application of HTLCM-assisted radiant cooling units in hot and humid regions is highlighted. • Material, mechanism, application of HTLCM-assisted radiant cooling are discussed. • Structural design, thermal performance, and cooling effective of RCAC are presented. • HTLCM improves condensation resistance, cooling capacity, temperature range of RCAC. • An updated review and discussion of HTLCM-assisted RCAC is provided. [ABSTRACT FROM AUTHOR]

Renewable energy is becoming increasingly popular in the development of low-carbon societies. Radiative sky cooling (RSC) technology utilizes long waves in the atmospheric window to radiate heat into outer space; it promises a good cooling effect and wide applicability. This paper reviews RSC technology in terms of its background, materials, heat transfer and influences, and applications in buildings. High-performance radiative cooling materials have been proposed to realize RSC during both the day and night. Using these materials, sky radiative coolers and cooling systems have been fabricated for different scenarios. Radiative and non-radiative heat transfer and cooling performances can be calculated or measured using the radiation law. The correlations between the sky effective radiative temperature and effective emissivity are summarized. Environment conditions affect the RSC performance, and the influences are systematically analyzed. Owing to its advantages of cleanliness, accessibility, and extensive resources, RSC technology can be applied to building envelopes and heating, ventilation, and air conditioning systems, to develop low-carbon and zero-energy buildings. Passive and active applications are also discussed. Finally, challenges of applying RSC technology to building systems are briefly discussed. This review should help promote the practice and implementation of RSC technology. • Spectrally selective radiative cooling materials and cooler forms are reviewed. • Heat-transfer parameters, performances and influences of RSC are summarized and analyzed. • Applications of RSC in building envelopes and HVAC systems are presented. • Challenges on RSC applied to buildings are discussed. [ABSTRACT FROM AUTHOR]

• DFT calculation fully supported the results predicted by CD-MUSIC model. • As(V) and Sb(V) exhibited a stronger affinity for bidentate coordination. • P(V) exhibited a stronger affinity for monodentate coordination. • The adsorption competitiveness of As(V) and P(V) was generally stronger than Sb(V). • Ion existing form and coordination structure affinity decided adsorption behavior. Despite the geochemical prominence of As(V), Sb(V), and P(V) coexisting in an extensive array of iron-oxide environments, the comprehension of their mobility and destiny is constrained due to the differences in the surface properties and exposed crystal facets of iron oxides. Herein, goethite primarily exposing the {1 1 0} facet, was employed as the model iron mineral to investigate the competitive adsorption behavior of As(V), Sb(V), and P(V) via batch experiments leveraging EXAFS, CD-MUSIC model, and DFT calculations. Results showed that observed co-adsorption behaviors were attributed to the comprehensive action of goethite surface chemistry, ion existing forms and different coordination structures stability at the molecular scale. CD-MUSIC model indicated As(V) and P(V) competed for surface sites through a combination of bidentate and monodentate coordination, whereas Sb(V) was primarily adsorbed via bidentate coordination, which led to the surpassed competitiveness of As(V) and P(V) on {1 1 0} facet compared to that of Sb(V). The affinity of various coordination structures on {1 1 0} facets based on DFT was found to be consistent with the trends predicted by the CD-MUSIC model. Specifically, As(V) and Sb(V) exhibited a greater affinity for bidentate coordination, while P(V) tended to form monodentate coordination complexes. However, the existing forms of As(V), Sb(V), and P(V) under different pH, especially for protonated species, accelerated the more weakened competitive combination ability of Sb(V) than As(V) and P(V) with increasing pH. Furthermore, charge density difference and Bader analysis have confirmed the contribution of electron transfer from the surface Fe to O towards forming Fe O bonds. This work provided a novel investigation way and facilitated a more profound understanding of the geochemical cycle of toxic metals. [ABSTRACT FROM AUTHOR]