Flexible Wearable Electronic Fabrics with Dual Functions of Efficient EMI Shielding and Electric Heating for Triboelectric Nanogenerators.

Traditional conductive fabrics are prepared by the synthesis of conductive polymers and the coating modification of metals or carbon black conductive materials. However, the conductive fabrics cause a significant decline in performance after washing or mechanical wear, which limits their application. Moreover, the single function of the traditional conductive fabric is also the reason that limits its wide application. In order to prepare a wearable, stable, high-performance, washable, multifunctional conductive fabric, we have carried out related research. In this work, polydopamine was used as a bonding layer, an adsorption reduction layer, and a protective layer to improve the bonding between silver nanoparticles and carbon nanotubes (CNTs) on the polyester fabric surface so as to prepare a multifunctional conductive fabric with a high-stability "sandwich" structure, in which a Ag-NPS@CNT structure acting as an intermediate conductive layer formed on the inner layer PDA@CNT by electroless silver plating and the outermost layer PDA@CNT coated on the surface of the intermediate conductive layer by the impregnation-drying method. The sheet resistance of an E-Fabric can reach 2.11 Ω/□ due to the uniform and dense conductive path formed by the special structure Ag-NPs@CNT. At a low voltage of 1.5 V, the E-Fabric can reach 117 °C in 50 s and remain stable. The electrical conductivity and current heating properties of the E-Fabric remain good even after multiple washing or bending tests. Due to its stable and outstanding electrical conductivity, the E-Fabric has an electromagnetic shielding efficiency (SET) of 35.3 dB in the X-band (8.2-12.4 GHz). In addition, E-Fabric-based spin-coated poly(methyl methacrylate) or polydimethylsiloxane electrodes exhibit excellent performance in nanogenerators. Through the low-frequency friction of the human body, transient voltages up to 4 V can be generated from a 2 cm × 2 cm electrode sample. The output power of a single generator can reach about 12 nW/cm2. Therefore, an E-Fabric is considered to have great potential in the fields of electric heating, electromagnetic shielding, and smart wearable devices.

Effects of Soundscape on Flow State during Diabolo Exercise.

"Soundscape" is defined as "an acoustic environment as perceived or experienced and/or understood by a person or people, in context." The research focuses on the physical properties of sound, paying attention to the relationship between the soundscape and people. Sports provide a comprehensive context, including the athletes, their behavior, the environment, spectators, and other elements. Soundscape in sports has many important functions, such as indicating the movement process, promoting positive emotions, and enhancing the entertainment atmosphere. It is also related to the physical and mental health of people who are exercising. As a technical sport with multidimensional soundscape qualities, diabolo is very popular among older adults in China due to its easy portability and operation. In order to explore the influence mechanism of the soundscape on the mental health of older players and better guide the shaping of soundscapes at sports venues, this paper focuses on soundscape perception and proposes a two-channel (direct and indirect) model of the influence of the diabolo soundscape on the psychological perception of older players. At the same time, we introduce the flow state as an indicator to evaluate mental health, and use the Short Flow State Scale (SFSS) to measure the flow state. By setting up a control experiment using the diabolo with and without sound and using the two-channel (direct and indirect) influence model to compare the differences in flow state scores under the two states, we analyzed the influence mechanism of the diabolo soundscape on the flow state of elderly groups. The results show that the scores of various flow state dimensions and total flow scores in the silent state of diabolo exercise are significantly lower than those in the sound state (p < 0.05 and p < 0.001), and the main differences are in the three dimensions of unambiguous feedback, sense of control, and autotelic experience. The two-channel influence model can effectively explain the differences in older adults' flow state, which provides a new comprehensive perspective to study the effect of the soundscape in sports on people's mental health.

Study on the sediment characteristics of the snow in a typical residential community and its integrated biological treatment pattern in Harbin.

Winter cities have severe shortages of water resources. The effective classification and recycling of urban water resources that are available here are therefore significant for the sustainable utilization of water in winter cities, and snow is a potential water resource. In this research, the water quality of the snow and the pollutant composition in the vehicle roads of a typical residential community of Harbin are analyzed. It is concluded that there is a large amount of suspended substances, including chemical oxygen demand (COD), salt, ammonia, and oil in this snow. There are 27 main pollutants. The oily substances are dominated by hexadecane and are accompanied by toxic substances, including benzene, toluene, ethylbenzene, xylene (BTEX), and naphthalene. As snow is a carrier of pollutants, the underground space of the urban shallow green belt is proposed to be used to establish a snow-melting system that would integrate biological treatment devices. This method allows the year-round collection, storage, and utilization of rainwater for use in city planning and municipal technology, realizing multiple objectives and having a significant influence on further urban development.