Interfacial solar vapor generation is an emerging technology that has the potential to alleviate the current global water crisis. However, water evaporation is an energy‐intensive phase‐change ...process and thus suffers from an inherently low evaporation yield. New stable and environmentally tolerant materials that can reduce energy requirements and accelerate water evaporation stand out from various studies. In this contribution, a piezoelectric ultrathin nanofilm is integrated into a solar evaporation membrane for simultaneous power generation and water activation. The resulting evaporator is used to continuously convert the wave energy in the ocean into electrical energy. It is found that the electrical energy generated by the evaporator can activate water in adjacent regions, facilitating water evaporation with an additional improvement of over 20% compared to an equivalent non‐piezoelectric evaporator. This paper presents the innovation of a promising membrane evaporation prototype based on the integration of wave‐triggered electricity and water activation.
A piezoelectric ultrathin nanofilm is integrated into a solar evaporation membrane, which triggers water activation nearby the electrical field generated through continuously converting wave energy in the ocean to electrical energy, thus facilitating water evaporation with an additional improvement of over 20% compared to an equivalent non‐piezoelectric evaporator.
Interfacial solar steam generation has been proved to be effective for desalination and water purification applications and a large number of smartly designed structures have been reported to reduce ...the heat conduction loss into bulk water by introducing thermally insulating porous foams. Actually, directly using air as the thermal insulation layer should be one of the most efficient ways to reduce the heat loss into bulk water. To this end, we present a bridge-arched hollow and self-floating integrative solar absorber/water evaporator prepared by a one-step hydrothermal reaction. The fully integrative water evaporator can achieve ∼92.9% water evaporation efficiency and 1.476 kg m
−2
h
−1
water evaporation rate under just 1 sun illumination. Such a high efficiency is caused by the unique bridge-arched raised upper surface, hollow interior, and tailored bilayer structure consisting of hydrophilic porous melamine foam for water transportation and a reduced graphene oxide layer for photothermal conversion. These features not only provide broadband solar absorption (∼95%), efficient light-to-heat conversion and a high water evaporation rate, but also suppress the heat loss at the same time. Owing to the simplicity of fabrication and recyclability, this novel composite structure is an ideal material for commercial, portable solar thermal conversion applications to obtain clean water
via
seawater desalination and wastewater purification.
A bridge-arched integrated evaporator that introduces air as the thermal insulation layer exhibits high-efficiency solar steam generation.
Solar energy triggered steam generation has emerged as a green and sustainable strategy that can potentially address the long-standing global freshwater scarcity issue. However, given that there is ...inadequate light illumination early in the morning or late afternoon or cloudy days, it is continuous steam generation in all weather that is a great challenge for the state-of-the-art solar-driven steam generators. Here, we present an all-weather-available steam generation system, which is capable of harvesting solar energy to continuously generate steam based on the alternative photo-thermal and electro-thermal conversion of crosslinked MXene aerogels (CMAs) in the day time and at night. In virtue of the strong light absorption and excellent electrical conductivity of the CMA, the constructed steam generation system can not only convert sunlight into heat for steam generation on sunny days but persistently achieve heat generation by utilization of electricity in low-light or dark circumstances. Furthermore, the ingenious introduction of solar cells-battery components makes full use of the daytime sunlight to further power the steam generation system for heating up the CMA at night, avoiding extra electrical energy input and loss. This work offers new insights into developing continuous steam generation technologies applicable to day-night alternation and complex environments.
An all-weather steam generation system is achieved based on the alternative photo-thermal and electro-thermal conversion of crosslinked MXene aerogels.
Most stretchable film strain sensors generally present nonlinear electrical responses to applied strain, leading to an inaccurate acquisition of sophisticated signals, difficult signal processing, ...and zero‐calibration, which hampers practical applications severely. Here, a Janus hetero‐structured microarray film sensor is developed by in‐situ growth of silver nanoparticles on the surface of micro‐patterned elastomer films fabricated via low‐temperature imprinting followed by scraping‐induced particle trapping. Heterogeneous property designs in both modulus and electrical conductivity via introducing polymer microarrays enable modulating the electron transport manner in the conductive layer of elastic Janus films upon stretching, allowing to tune signal linearity effectively. Therefore, such a hetero‐structured film sensor shows good signal linearity (fluctuation of gauge factor GF below ±0.02) and relatively high sensitivity (GF > 10) within 55% strain, a detection limit of 0.2% strain, and a response/recovery time of 16.3/46.9 ms, respectively. Correspondingly, it enables monitoring human respiration and body motion with higher resolution compared with the nonlinear one, meanwhile, it is capable of detecting tiny pressure to discriminate braille alphabets via touch identification. Overall, it unveils a simple strategy to fabricate film strain sensors for high‐resolution healthcare and body motion monitoring, as well as electronic skins toward tactile sensing and touch identification.
A Janus hetero‐structured microarray film strain sensor with linear and sensitive resistive response to strain is developed via low‐temperature imprinting followed by scraping‐induced particle trapping for healthcare and braille identification.
Acute kidney injury (AKI), as a common oxidative stress‐related renal disease, causes high mortality in clinics annually, and many other clinical diseases, including the pandemic COVID‐19, have a ...high potential to cause AKI, yet only rehydration, renal dialysis, and other supportive therapies are available for AKI in the clinics. Nanotechnology‐mediated antioxidant therapy represents a promising therapeutic strategy for AKI treatment. However, current enzyme‐mimicking nanoantioxidants show poor biocompatibility and biodegradability, as well as non‐specific ROS level regulation, further potentially causing deleterious adverse effects. Herein, the authors report a novel non‐enzymatic antioxidant strategy based on ultrathin Ti3C2‐PVP nanosheets (TPNS) with excellent biocompatibility and great chemical reactivity toward multiple ROS for AKI treatment. These TPNS nanosheets exhibit enzyme/ROS‐triggered biodegradability and broad‐spectrum ROS scavenging ability through the readily occurring redox reaction between Ti3C2 and various ROS, as verified by theoretical calculations. Furthermore, both in vivo and in vitro experiments demonstrate that TPNS can serve as efficient antioxidant platforms to scavenge the overexpressed ROS and subsequently suppress oxidative stress‐induced inflammatory response through inhibition of NF‐κB signal pathway for AKI treatment. This study highlights a new type of therapeutic agent, that is, the redox‐mediated non‐enzymatic antioxidant MXene nanoplatforms in treatment of AKI and other ROS‐associated diseases.
A novel non‐enzymatic antioxidant MXene nanoplatform with excellent biocompatibility and great chemical reactivity toward multiple ROS is developed to potentially scavenge the overexpressed ROS and subsequently suppress oxidative stress‐induced inflammatory response through the inhibition of NF‐κB signaling pathway in the prevention and treatment of AKI and other ROS‐related diseases.
The cosmopolitan pest Aphis gossypii (Glover) causes considerable economic losses on various crops by its feeding damage and transmitting diseases around the world. Flupyradifurone is a novel ...butenolide pesticide; its toxicity on A. gossypii parent generation (F0) was estimated following treatment with LC25 concentration for 48 h. The adult longevity and fecundity of the F0 individuals treated by flupyradifurone showed no significant decrease in comparison with the control. Life table method was used to evaluate the sublethal effects on progeny population (F1). Results showed that the development time of the fourth instar and the preadult as well as the total pre-reproductive period were significantly prolonged, while their fecundity was significantly decreased compared with the control. Additionally, the intrinsic rate of increase (r), the finite rate of increase (λ), and the net reproductive rate (R0) of F1 were all significantly lower in the group treated by LC25 than in the control group.These results reveal that the sublethal concentration of flupyradifurone could suppress the population growth of A. gossypii and indicate that this novel insecticide may be as a useful tool in pest management.
Solar interfacial vapor generation based on low evaporation energy requirements is an effective technology to speed up water purification under natural sunlight, offering great potential to alleviate ...the current global water crisis. The external electric field and hydrogel are two independent methods enabling low‐energy water evaporation. However, the complicated external equipment for generating an electric field and the restricted activation area of hydrogels significantly limit their practical application in steam generation. Thus, a piezoelectric fiber membrane is embedded into a highly hydratable light‐absorbing poly(vinyl alcohol) (PVA) hydrogel for synergistic water activation. The integrated evaporator is capable of continuously converting the wave energy reserved in the ocean into electrical energy, activating the water in the hydrogel. It is found that the activation effect leads to an improvement of over 23% compared to a non‐piezoelectric hydrogel evaporator. This work provides an evaporation prototype based on the synergistic water activation of wave‐triggered electricity and highly hydratable hydrogel.
A self‐powered solar water purification technique containing an all‐in‐one composite film evaporator composed of light‐absorbing hydrogel and piezoelectric fiber membrane, which triggers water activation in the hydrogel to synergistically combat the intrinsically high energy demand for water vaporization, thus delivering a high steam generation rate of 2.702 kg m−2 h−1 with an improvement of ≈23% compared to the non‐piezoelectric evaporator under one sun, is presented.
This work carried out liquid–solid two-phase jet experiments and simulations to study the erosion behavior of 304 stainless steel at 30° impingement. The single-phase impinging jet was simulated ...using dense grid by one-way coupling of solid phase due to its dilute distribution. The simulation results agreed well with experiments. It was found that after impinging particle attrition occurred and particles became round with decreasing length-ratio and particle breakage occurred along the “long” direction. Both experiment and simulations found that the erosion generated on the sample could be divided into three regions that were nominated as stagnant region, cutting transition region and wall jet region. Most particle–wall impacts were found to occur in the cutting transition region and the wall jet region. In the cutting transition region, holes and lip-shaped hogbacks were generated in the same direction as the flow imping. In the wall jet region, furrows and grooves were generated. The averaged grooves depth tended to become constant with the progress of impinging and reach the steady state of erosion in the end. In addition, it was found that impinging effect increased erosion and anti-wear rate.
Graphic abstract
Piezoelectric film pressure sensors are forthcoming choices for self-powered flexible and portable electronics because of their unique advantages in instant response and linear pressure-electrical ...signal relationship. However, it is commonly of challenge to achieve high output voltage response to pressure in piezoelectric polymer films. Here, we report a piezoelectric film pressure sensor fabricated by electrospun polyvinylidene-fluoride-trifluoroethylene (PVDF-TrFE)/MXene nanofiber mats. As a new two-dimensional nanomaterial, MXene has not only a large amount of surface functional groups to enable interaction with the dipoles of PVDF-TrFE molecular chains, but also high electrical conductivity to potentially increase the polarization of PVDF-TrFE during electrospinning. As such, by comparison with the control pressure sensor consisting of neat PVDF-TrFE film, the composite film sensor shows significantly improved output voltage, and the improvements are closely dependent on MXene content. For instance, the composite film with 2.0 wt% MXene can achieve an instantaneous output power density of ~3.64 mW/m2 under the pressure of 20 N with the frequency of 1 Hz. Such piezoelectric PVDF-TrFE/MXene films are capable of sensing body motion for healthcare. Furthermore, the hydrophilicity of MXene allows the film pressure sensor to monitor humidity change, thus the composite film sensor demonstrates potential application in multifunctional electronic skins.
The electrospun PVDF-TrFE/MXene composite film with good piezoelectric properties shows a good linear pressure-electrical signal response and ability of sensing human daily activities. Display omitted
Acute respiratory distress syndrome (ARDS) is an acute, severe, and refractory pulmonary inflammation with high morbidity and mortality. Excessive activation of fibroblast during the ...fibroproliferative phase plays a pivotal role in the prognosis of ARDS. Our previous study demonstrated that the vasoactive intestinal peptide (VIP) is mediated by lentivirus attenuates lipopolysaccharide (LPS)‐induced ARDS in a murine model, and VIP inhibits the release of interleukin‐17A (IL‐17A) from activation macrophages. However, the effects of VIP on the activation of murine fibroblast and expression of IL‐17 receptor (IL‐17R) in ARDS remain unclear. Here, a mouse model of ARDS was established by an intratracheal injection of LPS. We found that the gene expression of col3a1 and hydroxyproline contents in the lungs were significantly increased 24 h after LPS injection. IL‐17RC rather than IL‐17RA was increased in the lungs of mice with ARDS. In vitro, LPS activated NIH3T3 cells, which was suppressed by VIP in a dose‐dependent manner. In detail, VIP reduced the hydroxyproline content and col3a1 messenger RNA induced by LPS in NIH3T3 cells, as well as the expression of α‐smooth muscle actin. Furthermore, we found that VIP inhibited the expression of IL‐17R in the lungs of mice with ARDS and NIH3T3 cells stimulated with LPS, which was partly inhibited by antagonists of protein kinase A and protein kinase C. Taken together, our results demonstrated that VIP inhibited the activation of fibroblast via downregulation of IL‐17RC, which may contribute to the protective effects of VIP against ARDS in mice.
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