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Air-permeable building envelopes (APBEs) utilize the infiltrated or exfiltrated airflow within porous materials to directly change their temperature distribution to reduce heat loss/gain. APBEs effectively integrate building ventilation and heat recovery to achieve excellent thermal insulation while improving indoor air quality. This paper presents a comprehensive review of the fundamentals and classifications, historical evolution over time, opportunities and benefits, and future views on APBEs. It can be treated as a responsive building envelope that enables building envelopes to dynamically change the U-values by varying the infiltrated or exfiltrated airflow rate within a porous material. Previous studies have indicated that the U-value of 0.1 W/(m2·K) can be realized by employing APBEs. Moreover, some research demonstrates that APBEs could act as high-performance air filters that reduce over 90% of particulate matter within fresh, ventilated air. Some factors, such as airflow rate, thickness, and thermal conductivity of porous materials, have a significant influence on the effectiveness of APBEs. For practical applications, integrating the APBE with passive building ventilation can help reduce the initial cost and facilitate decarbonization in buildings. Moreover, advanced control strategies could collaboratively optimize the operation of ABPEs and build energy systems to maximize their energy-saving potential. [ABSTRACT FROM AUTHOR]

Semantic segmentation is significant for robotic indoor activities. However, relying solely on RGB modality often leads to poor results due to limited information. Introducing other modalities can improve performance but also increases complexity and cost, making it unsuitable for real-time robotic applications. To address the balance issue of performance and speed in robotic indoor scenarios, we propose an interactive efficient multitask RGB-D semantic segmentation network (IEMNet) that utilizes both RGB and depth modalities. On the premise of ensuring rapid inference speed, we introduce a cross-modal feature rectification module, which calibrates the noise of RGB and depth modalities and achieves comprehensive cross-modal feature interaction. Furthermore, we propose a coordinate attention fusion module to achieve more effective feature fusion. Finally, an instance segmentation task is added to the decoder to assist in enhancing the performance of semantic segmentation. Experiments on two indoor scene datasets, NYUv2 and SUNRGB-D, demonstrate the superior performance of the proposed method, especially on the NYUv2, achieving 54.5% mIoU and striking an excellent balance between performance and inference speed at 42 frames per second. [ABSTRACT FROM AUTHOR]

This study investigated the air quality and ventilation systems of 22 public toilets in 10 railway stations in China. Approximately 80% of public toilets meet the standard for ammonia concentration in Class I toilets, while 20% exceed the standard. It was found that the concentration of pollutants is mainly related to the number of toilet users and the ventilation system. In 20% of public toilets, the change in ammonia concentration was delayed by about 1 to 2 h with the change in hourly service number. In order to improve the air quality, a design method for calculating the number of toilet cubicles was proposed. Results show that the service capacity of the cubicle per hour (SCCH) of a female toilet is 12, the SCCH of male toilets is related to the ratio of squatting pans to urinals (RSU), which is suggested to be 1:1~1:0.8, and the corresponding SCCH is 16~20. Then, the effect of different ventilation forms was simulated by computational fluid dynamics (CFD) 2019 software. The results show that the bottom exhaust was better than the top exhaust and that the fresh air supply system is unnecessary. The recommended ventilation rate for toilets is 20 air changes per hour (ACH). The scale design method of toilets proposed in this paper was meant to address the gender imbalance and avoid queuing and provides a reference for the renovation and design of public toilets. [ABSTRACT FROM AUTHOR]

The first example of paired electrolysis-enabled cyanation of diaryl diselenides, with KSCN as the green cyanating agent, has been developed. A broad range of aryl selenocyanates can be efficiently synthesized under chemical-oxidant- and additive-free, energy-saving and mild conditions. [ABSTRACT FROM AUTHOR]

Most reported wearable electronic devices lack self-healing chemistry and flexible function to maintain stable energy output while irreversible damages and complex deformations. In this work, we report a dual-dynamic network electrolyte synthesized by micellar elastomers introduced into strong hydrogel matrix. The gel electrolyte is fabricated by physically cross-linking the borax-polyvinyl alcohol (B-PVA) network as tough matrix and poly (ethylene oxide) (PEO)-poly (propylene oxide) (PPO)-poly (ethylene oxide) (Pluronic) to frame elastic network, followed by immersion in potassium chloride solution. Under the action of dynamic borate ester bond and multi-network hydrogen bond, the as-prepared electrolyte exhibits high stretchability (1535%) and good self-healing efficiency. Based on the electrolyte, we assemble the interfacial compatible micro-supercapacitor (MSC) by multi-walled carbon nanotubes (MWCNT) interdigital electrode printed on cellulosic paper by direct ink writing (DIW) technique. Thanks to the large specific area and compressive deformation resistance of cellulosic paper, the MSC with tightly interfacial contact achieves high volumetric capacitance of 801.9 mF cm−3 at the current density of 20 μA cm−2. In the absence of stimulation of the external environment, the self-healing MSC demonstrates an ideal capacity retention (90.43%) after five physical damaged/healing cycles. Our research provides a clean and effective strategy to construct wearable MSC. [ABSTRACT FROM AUTHOR]

Flavonoids are natural polyphenolic compounds produced by many aquatic plants and released in their environments. In this study, the effects of several aquatic flavonoids on cyanobacterial Microcystis aeruginosa, especially in relation to the cell growth, photosynthetic activity, cell morphology, and cell membrane integrity, were investigated. Significant growth inhibition was observed when the cyanobacteria were exposed to three flavonoids, namely, 5,4'-dihydroxyflavone (DHF), apigenin, and luteolin. Luteolin reduced the effective quantum yield, photosynthetic efficiency, and maximal electron transport rate by 70%, 59% and 44%, respectively, whereas 5,4'-DHF and apigenin slightly affected these parameters, which implies that luteolin disrupts the photosynthetic system. Moreover, 5,4'-DHF and apigenin compromised the membrane integrity, and induced membrane depolarization in 52% and 38%, and permeabilization in 30% and 44% of the cells, respectively. The 5,4'-DHF and apigenin showed more pronounced effects on M. aeruginosa morphology and membrane integrity, compared to the luteolin. These results suggest that flavonoids could have significant effects on growth and physiological functions in cyanobacterial species.