RESUMEN
Drought and water scarcity are two of the world's major problems. Solar-powered sorption-based atmospheric water harvesting technology is a promising solution in this category. The main challenge is to design materials with high water harvesting performance while achieving fast water vapor adsorption/desorption rates. Here, a superhydrophilic photothermic hollow nanocapsule (SPHN) is represented that achieves efficient atmospheric water harvesting in outdoor climates. In SPHN, the hollow mesoporous silica (HMS) is grafted with polypyrrole (PPy) and also loaded with lithium chloride (LiCl). The hollow structure is used to store water while preventing leakage. The hydrophilic spherical nanocapsule and the trapped water produce more free and weakly adsorbed water. Significantly lower the heat of desorption compared to pure LiCl solution. Such SPHN significantly improves the adsorption/desorption kinetics, e.g., absorbs 0.78-2.01 g of water per gram of SPHN at 25 °C, relative humidity (RH) 30-80% within 3 h. In particular, SPHN has excellent photothermal properties to achieve rapid water release under natural sunlight conditions, i.e., 80-90% of water is released in 1 h at 0.7-1.0 kW m-2 solar irradiation, and 50% of water is released even at solar irradiation as low as 0.4 kW m-2 . The water collection capacity can reach 1.2 g g-1 per cycle by using the self-made atmospheric water harvesting (AWH) device. This finding provides a way to design novel materials for efficient water harvesting tasks, e.g., water engineering, freshwater generator, etc.
RESUMEN
Photothermal superhydrophobic surfaces are potential to become ideal anti-/deicing surfaces due to their rapid water removal, icing delay, and photothermal deicing performance. Here, a robust photothermal icephobic surface with mechanical durability is shown that is integrated with a microspine array inspired by honeycomb and cactus thorn (i.e., MAHC), which is developed by a laser-layered microfabrication strategy. The maximum stress on the microspine of the MAHC is reduced by ≈2/3, due to the protection of the bionic honeycomb structure. Even after 200 linear abrasions by a steel blade, the MAHC remains superior water repellency with a water contact angle of 150.7° and roll-off angles of 10.3°, stable icing delay time (578.2 s), and rapidly photothermal deicing capabilities (401 s). As the MAHC is fabricated on a curvature surface such as a copper alloy transmission line for an overhead high-speed rail, a stable photothermal anti-/deicing in a low-temperature environment still can be achieved effectively. The freezing rain covering the functional transmission line completely slides off within 758 s under one sun illumination. This studying offers insight into the design of novel materials with stable anti-icing/icephobic structures, which would be extended into some applied realms, for example, transportation fields or power systems in cold or low-temperature climates.
RESUMEN
A Gradient-Janus wire (GJW) with a diameter of 0.3 mm has been fabricated on a large scale through liquid confined modification, enabling the opposite conical wetting phenomenon along the same orientation of the GJW, characterized by an increasing superhydrophilic region and a decreasing hydrophobic region. This property allows the GJW to exhibit controllable water hovering, transport, and pinning during fog harvesting, i.e., at a large tilting angle α of 60° (mass increased with decreased α), the GJW can hover 0.6 mg of harvested fogwater in 30 s, can transport 3 mg of fogwater along the gradient in 30 s at α = 4° (with maximal mass reaching up to 4.3 mg at α = -10°), and finally, pin the water droplet at the end of the GJW. Such ability generates an effective torque that serves as the driving force for rotation. We designed a GJWs-wheel by radially arranging 60 GJWs together, resulting in an extremely lightweight structure weighing only 1.9 g. The cumulative torque generated during fog harvesting activates the rotation of the GJWs-wheel. When loaded with a coil within a magnetic field, electricity is generated as output power peaks at around 0.25 µW while maintaining a high water harvesting efficiency averaging approximately 38 ± 2.12 mg/min. This finding is significant as it provides valuable insights into designing materials capable of efficiently harnessing both energy and water resources.
RESUMEN
BACKGROUND: A simple scoring system for triage of suspected patients with COVID-19 is lacking. METHODS: A multi-disciplinary team developed a screening score taking into account epidemiology history, clinical feature, radiographic feature, and routine blood test. At fever clinics, the screening score was used to identify the patients with moderate to high probability of COVID-19 among all the suspected patients. The patients with moderate to high probability of COVID-19 were allocated to a single room in an isolation ward with level-3 protection. And those with low probability were allocated to a single room in a general ward with level-2 protection. At the isolation ward, the screening score was used to identify the confirmed and probable cases after two consecutive real-time reverse transcription polymerase chain reaction (RT-PCR) tests. The data in the People's Hospital of Changshou District were used for internal validation and those in the People's Hospital of Yubei District for external validation. RESULTS: We enrolled 76 and 40 patients for internal and external validation, respectively. In the internal validation cohort, the area under the curve of receiver operating characteristics (AUC) was 0.96 [95% confidence interval (CI): 0.89-0.99] for the diagnosis of moderate to high probability of cases among all the suspected patients. Using 60 as cut-off value, the sensitivity and specificity were 88% and 93%, respectively. In the isolation ward, the AUC was 0.94 (95% CI: 0.83-0.99) for the diagnosis of confirmed and probable cases. Using 90 as cut-off value, the sensitivity and specificity were 78% and 100%, respectively. These results were confirmed in the validation cohort. CONCLUSION: The scoring system provides a reference on COVID-19 triage in fever clinics to reduce misdiagnosis and consumption of protective supplies.The reviews of this paper are available via the supplemental material section.