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Significant progress has been made in direct air capture (DAC) in recent years. Evidence suggests that the large-scale deployment of DAC by adsorption would be technically feasible for gigatons of CO2 capture annually. However, great efforts in adsorption-based DAC technologies are still required. This review provides an exhaustive description of materials development, adsorbent shaping, in situ characterization, adsorption mechanism simulation, process design, system integration, and techno-economic analysis of adsorption-based DAC over the past five years; and in terms of adsorbent development, affordable DAC adsorbents such as amine-containing porous materials with large CO2 adsorption capacities, fast kinetics, high selectivity, and long-term stability under ultra-low CO2 concentration and humid conditions. It is also critically important to develop efficient DAC adsorptive processes. Research and development in structured adsorbents that operate at low-temperature with excellent CO2 adsorption capacities and kinetics, novel gas-solid contactors with low heat and mass transfer resistances, and energy-efficient regeneration methods using heat, vacuum, and steam purge is needed to commercialize adsorption-based DAC. The synergy between DAC and carbon capture technologies for point sources can help in mitigating climate change effects in the long-term. Further investigations into DAC applications in the aviation, agriculture, energy, and chemical industries are required as well. This work benefits researchers concerned about global energy and environmental issues, and delivers perspective views for further deployment of negative-emission technologies.
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Aminas , Dióxido de Carbono , Adsorción , Aminas/química , Dióxido de Carbono/química , Cinética , PorosidadRESUMEN
Phase change materials (PCMs) are regarded as promising candidates for realizing zero-energy thermal management of electronic devices owing to their high thermal storage capacity and stable working temperature. However, PCM-based thermal management always suffers from the long-standing challenges of low thermal conductivity and liquid leakage of PCMs. Herein, a dual-encapsulation strategy to fabricate highly conductive and liquid-free phase change composites (PCCs) for thermal management by constructing a polyurethane/graphite nanoplatelets hybrid networks is reported. The PCM of polyethylene glycol (PEG) is first infiltrated into the cross-linked network of polyurethane (PU) to synthesize hybridized semi-interpenetrated composites (PEG@PU), and then incorporated with reticulated graphite nanoplatelets (RGNPs) via pressure-induced assembly to fabricate highly conductive PCCs (PEG@PU-RGNPs). The hybrid networks enable the PCCs to show excellent mechanical strength, liquid-free phase change, and stable thermal property. Notably, the dual-encapsulated PCCs exhibit high thermal and electrical conductivities up to 27.0 W m-1 K-1 and 51.0 S cm-1 , superior to the state-of-the-art PEG-based PCCs. Furthermore, the PCC-based energy device is demonstrated for efficient battery thermal management toward versatile demands of active preheating at a cold environment and passive cooling at a hot ambient. Overall, this work provides a promising route for fabricating highly conductive and liquid-free PCCs toward thermal management.
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Freshwater scarcity is a global challenge threatening human survival, especially for people living in arid regions. Sorption-based atmospheric water harvesting (AWH) is an appealing way to solve this problem. However, the state-of-the-art AWH technologies have poor water harvesting performance in arid climates owing to the low water sorption capacity of common sorbents under low humidity conditions. We report a high-performance composite sorbent for efficient water harvesting from arid air by confining hygroscopic salt in a metal-organic framework matrix (LiCl@MIL-101(Cr)). The composite sorbent shows 0.77â g g-1 water sorption capacity at 1.2â kPa vapor pressure (30 % relative humidity at 30 °C) by integrating the multi-step sorption processes of salt chemisorption, deliquescence, and solution absorption. A highly efficient AWH prototype is demonstrated with LiCl@MIL-101(Cr) that can enable the harvesting of 0.45-0.7â kg water per kilogram of material under laboratory and outdoor ambient conditions powered by natural sunlight without optical concentration and additional energy input.
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OBJECTIVE: -microRNAs (miRNAs) have emerged as novel regulators for cardiac hypertrophy. MiR-122 is well recognized as a promising therapeutic target in liver disease, whereas recently plays important roles in cardiovascular diseases. The current study aimed to explore the effect of miR-122 on the pathogenesis of cardiomyocyte hypertrophy. METHODS AND RESULTS: -The cardiomyocytes isolated from the neonatal rat ventricular cardiomyocytes (NRVMs) were collected and performed to Angiotensin II (Ang II) administration. We observed a dramatically increased miR-122 expression in hypertrophic cardiomyocytes. The NRVMs transfected with miR-122 mimic or negative control were utilized for the functional analysis. Overexpression of miR-122 increased the morphology size of cardiomyocytes and promoted the pro-hypertrophic genes expression, whereas downregulated the anti-hypertrophic genes upon Ang II stimulation. The bioinformatics analysis and luciferase reporter assays exhibited that miR-122 directly targeted FoxO3 and attenuated its gene level in hypertrophic cardiomyocytes. Moreover, miR-122 negatively regulated FoxO3 but promoted calcineurin signaling pathway activation. Importantly, FoxO3 overexpression significantly reversed the effect of miR-122 on cardiomyocyte hypertrophy. CONCLUSION: -Collected, our finding demonstrated that miR-122 accelerated the development of cardiomyocytes hypertrophy partially via directly regulation of FoxO3-calcineurin pathway.
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Cardiomegalia/genética , Proteína Forkhead Box O3/genética , Regulación de la Expresión Génica/genética , MicroARNs/genética , Miocitos Cardíacos/metabolismo , Angiotensina II/farmacología , Animales , Animales Recién Nacidos , Calcineurina/metabolismo , Cardiomegalia/metabolismo , Cardiomegalia/patología , Tamaño de la Célula/efectos de los fármacos , Células Cultivadas , Proteína Forkhead Box O3/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Miocitos Cardíacos/citología , Miocitos Cardíacos/efectos de los fármacos , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Vasoconstrictores/farmacologíaRESUMEN
Removing benzene from indoor space plays an important role in indoor air purification. A novel filter with vegetal fiber paper (VFP) as matrix hosting silica gel is proposed in this paper for benzene removal. In order to investigate the feasibility and performance of this idea, firstly, three pieces of VFP samples impregnated with different amounts of silica gel are fabricated and their benzene adsorption quantities are tested. The results show that three times is recommended as the optimal number for impregnating. The VFP sample impregnated with silica gel after the third impregnating exhibits commendable coating stability and good benzene adsorption performance. Additionally, at low relative pressure (Pb /Ps ≤ 0.05), the experimental data of benzene adsorption isotherms fit well with the Langmuir model with R2 greater than 0.97. Then, two actual filters made of VFP impregnated with silica gel after the third impregnating were fabricated. It is found that the pressure drop of the actual filter is only 1200 Pa/m when the air velocity is 2 m/s. Besides, the one-pass efficiency of the filter can reach to 19.44%. It is expected that the silica gel coated on the filter can be modified to improve the purification performance of the filter.
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Contaminantes Atmosféricos/aislamiento & purificación , Benceno/aislamiento & purificación , Papel , Proteínas de Plantas , Gel de Sílice , Adsorción , Contaminación del Aire Interior , Estudios de FactibilidadRESUMEN
The aim of this study was to explore the role and regulatory mechanism of microRNA-298 (miR-298) in myocardial ischemic injury. H9c2 cardiomyocytes were cultured under hypoxia (3 % O2) conditions to induce myocardial ischemic injury. Subsequently, the effects of miR-298 overexpression and suppression on hypoxia-induced myocardial damage in H9c2 cells were investigated. Moreover, the target of miR-298 was identified in H9c2 cells and the relationship between miR-298 and the activation of PTEN/PI3K/AKT signaling pathway was explored. miR-298 was upregulated in hypoxia-stimulated H9c2 cells. Overexpression of miR-298 distinctly aggravated hypoxia-induced myocardial damage in hypoxia-treated H9c2 cells, whereas inhibition of miR-298 alleviated hypoxia-induced injury. Moreover, miR-298 negatively regulated the expression of cyclin D1, and cyclin D1 was a target of miR-298 in H9c2 cells. Suppression of cyclin D1 significantly reversed the effects of suppression of miR-298 on hypoxia-induced myocardial damage. Lastly, inhibition of miR-298 activated the PTEN/PI3K/AKT signaling pathway, and this effect could be reversed after suppression of cyclin D1. Our results reveal that miR-298 may exacerbate myocardial ischemic injury by targeting cyclin D1 and regulating the activation of PTEN/PI3K/AKT signaling pathway. miR-298 may serve as a promising targets for reducing myocardial ischemic injury.
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Ciclina D1/genética , Ciclina D1/metabolismo , MicroARNs/metabolismo , Daño por Reperfusión Miocárdica/genética , Daño por Reperfusión Miocárdica/metabolismo , Hipoxia de la Célula/genética , Línea Celular , MicroARNs/fisiología , Fosfohidrolasa PTEN/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de SeñalRESUMEN
Concentrating the concept of a beam-down solar tower with linear Fresnel heliostat (PLCF) is one of the feasible choices and has great potential in reducing spot size and improving optical efficiency. Optical characteristics of a PLCF system with the hyperboloid reflector are introduced and investigated theoretically. Taking into account solar position and optical surface errors, a Monte Carlo ray-tracing (MCRT) analysis model for a PLCF system is developed and applied in a comparison-based study on the optical performance between the PLCF system and the conventional beam-down solar tower system with flat and spherical heliostats. The optimal square facet of linear Fresnel heliostat is also proposed for matching with the 3D-CPC receiver.
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Decidual stromal cells (DSCs) from maternal term placenta represent a potential source of cells for the treatment of cardiovascular and graft-versus-host diseases. However, it is not clear whether DSCs could be induced towards cardiomyocyte-like differentiation. We chose the placentas which should bred male new-baby. We isolated DSCs from placenta by tissue adherence. The morphology, immunophenotype, and multi-lineage potential were analyzed. Karyotype analysis (G-band) was performed to determine the source and karyotype stability of DSCs. DSCs were induced by 5-azacytidine. Expression of Myf5, α-cardiac actin, Cardiac troponin T (cTnT) and GAPDH was assessed by PCR, and cTnT expression was also analyzed by immunofluorescence. Karyotype analyses indicated that cells were derived from the maternal matrix. After induction with 5-azacytidine, DSCs expressed the cardiac-specific markers Myf5, myogenin and cTnT, indicating differentiation towards cardiomyocyte-like cells.
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Azacitidina/farmacología , Decidua/citología , Miocitos Cardíacos/citología , Miocitos Cardíacos/fisiología , Células Madre/citología , Células Madre/fisiología , Técnicas de Cultivo Celular por Lotes/métodos , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/fisiología , Células Cultivadas , Medio de Cultivo Libre de Suero , Decidua/efectos de los fármacos , Decidua/fisiología , Inhibidores Enzimáticos/administración & dosificación , Estudios de Factibilidad , Femenino , Humanos , Miocitos Cardíacos/efectos de los fármacos , Embarazo , Células Madre/efectos de los fármacos , Ingeniería de Tejidos/métodosRESUMEN
Mesenchymal stem cells (MSCs) are multipotent adult stem cells that have an immunosuppressive effect. The biological stability of MSCs in serum-free medium during long-term culture in vitro has not been elucidated clearly. The morphology, immunophenotype and multi-lineage potential were analyzed at passages 3, 5, 10, 15, 20, and 25 (P3, P5, P10, P15, P20, and P25, respectively). The cell cycle distribution, apoptosis, and karyotype of human umbilical cord-derived (hUC)-MSCs were analyzed at P3, P5, P10, P15, P20, and P25. From P3 to P25, the three defining biological properties of hUC-MSCs [adherence to plastic, specific surface antigen expression, multipotent differentiation potential] met the standards proposed by the International Society for Cellular Therapy for definition of MSCs. The cell cycle distribution analysis at the P25 showed that the percentage of cells at G0/G1 was increased, compared with the cells at P3 (P < 0.05). Cells at P25 displayed an increase in the apoptosis rate (to 183 %), compared to those at P3 (P < 0.01). Within subculture generations 3-20 (P3-P20), the differences between the cell apoptotic rates were not statistically significant (P > 0.05). There were no detectable chromosome eliminations, displacements, or chromosomal imbalances, as assessed by the karyotyping guidelines of the International System for Human Cytogenetic Nomenclature (ISCN, 2009). Long-term culture affects the biological stability of MSCs in serum-free MesenCult-XF medium. MSCs can be expanded up to the 25th passage without chromosomal changes by G-band. The best biological activity period and stability appeared between the third to 20th generations.
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Técnicas de Cultivo de Célula/métodos , Medio de Cultivo Libre de Suero/farmacología , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/efectos de los fármacos , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Homólogo de la Proteína Chromobox 5 , Humanos , Trasplante de Células Madre Mesenquimatosas , Factores de Tiempo , Cordón Umbilical/citología , Cordón Umbilical/efectos de los fármacosRESUMEN
OBJECTIVES: To evaluate the psychological quality and its influencing factors of mine rescue staff. METHODS: A total of 310 on front line rescue staff from the mines in Tangshan were sampled by random cluster sampling method.Our own designed measurement tools for psychological quality, including Eysenck personality questionnaire (EPQ), attention test scale, willpower test scale and reactive agility test were used to investigate the psychological quality of mine rescue staff. All tests were conducted in quiet state.Other information including age, length of service for rescue, sex, education, smoking and drinking, and so on were collected at the same time. The mood and influencing factors on psychological quality of the rescue staff were also analyzed. RESULTS: The personality traits of mine rescue staff are close to the national norm.0.6% (2/310) staff showed weak willpower.20.7% (64/310) staff had unstable mood. The E and N factor scores in 20-29 years old group (12.7 ± 4.3 and 12.1 ± 5.1) were higher than 30-39, 40-49, 50-59 years old groups (E factor scores:11.4 ± 3.9, 10.6 ± 3.7 and 10.7 ± 3.9; N factor scores:11.0 ± 5.1, 9.4 ± 4.9 and 6.3 ± 3.4, respectively) (FE = 4.28, FN = 11.35, all P < 0.01) . The L factor score in 40-49 and 50-58 years old groups (13.0 ± 4.2 and 14.8 ± 3.6) were higher than 20-29 and 30-39 years old groups (11.5 ± 3.8 and 12.2 ± 3.8) (F = 6.08, P < 0.01) . Multivariate analysis found that the psychological quality of mine rescue staff was mainly influenced by the length of service (ß'E factor = -0.12, ß'willpower = -0.12), the amount of participating rescue (ß'P factor = 0.12, ß'N factor = -0.14), alerting duty (ß'L factor = 0.16, ß 'error number of target tracking = -0.161) , daily training (ß'attention = 0.22,ß'total number of aimed at the test = -0.18) and life events (ß'N factor = -0.14,ß'L factor = 0.13,ß'correct number of target tracking = -0.18). CONCLUSION: The mine rescue staff had high level psychological quality, length of service. the amount of participating rescue, and life events in the year effect the psychological quality of mine rescue staff.
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Socorristas/psicología , Minería , Trabajo de Rescate , Estrés Psicológico , Adulto , Estudios Transversales , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida , Encuestas y Cuestionarios , Adulto JovenRESUMEN
OBJECTIVE: To investigate psychological stress and influence factors on the mine emergency rescue personnel. METHOD: 564 mine emergency rescue personnel from a rescue group were select as subjects, and 60 designers from a steel design institute were as controls. Self-made questionnaire and general job stress questionnaire were used to investigate the basic information, rescue history, psychosomatic symptoms, depression symptoms, daily job stress and negative emotions of emergency rescue personnel. SPSS17.0 software was used to analysis the psychological stress on the mine rescue personnel and its influence factors. RESULTS: The detection rate (41.94%) of depression symptoms in rescue team was higher than that of controls (24.90%). The score of daily job stress was higher than that of logistical support. The older age group with higher negative emotional and daily job stress than the younger. The highest negative emotion was in age group of more than 40 years old. The highest score of daily job stress was in ≤30 years old. The score of depression and psychosomatic symptoms were higher than those of the college and the above. The scores of depression in group of duration of rescue <10 years was higher than that of duration≥10 years. The score of daily job stress is the lowest in rescue for 1 to 2 times per year and the highest in group of simulation training once a week. The score of daily job stress and depressive symptoms were getting higher with the extension of combat duty time. Age, hours of combat duty, training times a week, education and life events were the main affecting fectors on mental health of mine rescuers. CONCLUSIONS: Mine rescuers have more psychological stress than generic population. The psychological stress of the mine crew is related to age, education, life events, training and combat readiness duty time.
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Socorristas/psicología , Minería , Trabajo de Rescate , Estrés Psicológico , Adulto , Estudios Transversales , Depresión , Desastres , Humanos , Salud Mental , Encuestas y CuestionariosRESUMEN
Background: percutaneous coronary intervention (PCI) has become the mainstay of treatment for atherosclerotic cardiovascular disease (ASCVD). Inflammatory factors have been shown to be involved in the initiation and progression of ASCVD. After PCI, the persistence of inflammation, especially the inflammation released at the target lesion, may affect the stability of non-target lesion plaques. Interleukin-6 (IL-6) is one of the most common inflammatory factors, however studies about the influence of IL-6 on the progression of non-target lesions (NTLs) of coronary artery are limited. This study investigated whether serum IL-6 levels can affect the progression of NTLs after coronary stent implantation. Methods: We performed a retrospective cohort study including 441 patients undergoing coronary angiography (CAG) and stent implantation, who had at least one NTL, between January 2019 and December 2021. They underwent followup CAG 9 to 12 months after PCI. Quartile grouping was based on serum IL-6 levels following readmission. The relationship between serum IL-6 levels and the progression of NTLs after coronary stent implantation was analyzed by using logistic regression analysis and restricted cubic spline regression. Predictive value of IL-6 on NTL progression was evaluated using the receiver operating characteristic (ROC) curve. Results: When compared to the first quartile (Q1) group, the probability of NTL progression was increased in Q2 (adjusted odds ratio (aOR) 3.06, 95% CI 1.29-7.29), Q3 (aOR 3.55, 95% CI 1.52-8.26), and Q4 group (aOR 7.51, 95% CI 3.30-17.05), with a trend test p < 0.001. With the increase of IL-6 levels, the risk of progression of NTLs gradually increased, and there was a non-linear relationship between IL-6 and progression of NTLs (p < 0.001). The ROC curve showed that the critical value of the serum IL-6 level was 12.652 pg/mL (area under the curve is 0.673, sensitivity is 54.5%, specificity is 70.9%, p < 0.05). Conclusions: A high serum IL-6 level is an independent risk factor for the progression of NTLs after coronary stent implantation, and has certain predictive value for the progression of NTLs.
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Droplet impact is a ubiquitous liquid behavior that closely tied to human life and production, making indispensable impacts on the big world. Nature-inspired superhydrophobic surfaces provide a powerful platform for regulating droplet impact dynamics. The collision between classic phenomena of droplet impact and the advanced manufacture of superhydrophobic surfaces is lighting up the future. Accurately understanding, predicting, and tailoring droplet dynamic behaviors on superhydrophobic surfaces are progressive steps to integrate the droplet impact into versatile applications and further improve the efficiency. In this review, the progress on phenomena, mechanisms, regulations, and applications of droplet impact on superhydrophobic surfaces, bridging the gap between droplet impact, superhydrophobic surfaces, and engineering applications are comprehensively summarized. It is highlighted that droplet contact and rebound are two focal points, and their fundamentals and dynamic regulations on elaborately designed superhydrophobic surfaces are discussed in detail. For the first time, diverse applications are classified into four categories according to the requirements for droplet contact and rebound. The remaining challenges are also pointed out and future directions to trigger subsequent research on droplet impact from both scientific and applied perspectives are outlined. The review is expected to provide a general framework for understanding and utilizing droplet impact.
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Sorption-based atmospheric water harvesting (SAWH) has received unprecedented attention as a future water and energy platform. However, the water productivity of SAWH systems is still constrained by the slow sorption kinetics at material and component levels and inefficient condensation. Here, we report a facile method to prepare hygroscopic interconnected porous gel (HIPG) with fast sorption-desorption kinetics, high scalability and stability, and strong adhesion property for highly efficient SAWH. We further design a solar-wind coupling driven SAWH device with collaborative heat and mass enhancement achieving continuous water production. Concentrated sunlight contributes to enhancing the desorption and condensation synergistically, and natural wind is introduced to drive the device operation and improve the sorption kinetics. The device demonstrated record high working performance of 14.9 Lwater m-2 day-1 and thermal efficiency of 25.7% in indoor experiments and 3.5-8.9 Lwater m-2 day-1 in outdoor experiments by solar concentration without any other energy consumption. This work provides an up-and-coming pathway to realize highly efficient and sustainable clean water supply for off-grid and arid regions.
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Sorption-based atmospheric water harvesting holds promise for alleviating water scarcity, but current prototypes have not shown significant increases in practical yields despite efforts in the enlarged engineering scale. This is due to weakened heat and mass transfer with a packed sorbent bed. In this work, the desiccant-coated adsorbers were employed to fabricate the water harvesting device that incorporates internal fluid for cooling and heating during sorption and desorption. Featured with an internal cooling effect, practical water productivity could be improved by 1.75-9.96 times with a low desorption temperature (45-62 °C). The continuous water harvesting system could produce 0.77-3.98 Lwater/kgsorbent/day with a thermal energy consumption of 7.7-30.4 MJ/kg in wide climates from 20 % to 80 % RH, providing a reference for device design in the engineering view. The demonstration revealed that using natural cooling in the sorption stage has great benefits in improving water harvesting performance, which can be integrated into the building sectors or a wider range of scenarios.
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Agua , Agua/química , Adsorción , Temperatura , Abastecimiento de AguaRESUMEN
Establishing alternative methods for freshwater production is imperative to effectively alleviate global water scarcity, particularly in land-locked arid regions. In this context, extracting water from the ubiquitous atmospheric moisture is an ingenious strategy for decentralized freshwater production. Sorption-based atmospheric water harvesting (SAWH) shows strong potential for supplying liquid water in a portable and sustainable way even in desert environments. Herein, the latest progress in SAWH technology in terms of materials, devices, and systems is reviewed. Recent advances in sorbent materials with improved water uptake capacity and accelerated sorption-desorption kinetics, including physical sorbents, polymeric hydrogels, composite sorbents, and ionic solutions, are discussed. The thermal designs of SAWH devices for improving energy utilization efficiency, heat transfer, and mass transport are evaluated, and the development of representative SAWH prototypes is clarified in a chronological order. Thereafter, state-of-the-art operation patterns of SAWH systems, incorporating intermittent, daytime continuous and 24-hour continuous patterns, are examined. Furthermore, current challenges and future research goals of this cutting-edge field are outlined. This review highlights the irreplaceable role of heat and mass transfer enhancement and facile structural improvement for constructing high-yield water harvesters.
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Water is the source of life and civilization, but water icing causes catastrophic damage to human life and diverse industrial processes. Currently, superhydrophobic surfaces (inspired by the lotus effect) aided anti-icing attracts intensive attention due to their energy-free property. Here, recent advances in anti-icing by design and functionalization of superhydrophobic surfaces are reviewed. The mechanisms and advantages of conventional, macrostructured, and photothermal superhydrophobic surfaces are introduced in turn. Conventional superhydrophobic surfaces, as well as macrostructured ones, easily lose the icephobic property under extreme conditions, while photothermal superhydrophobic surfaces strongly rely on solar illumination. To address the above issues, a potentially smart strategy is found by developing macrostructured photothermal storage superhydrophobic (MPSS) surfaces, which integrate the functions of macrostructured superhydrophobic materials, photothermal materials, and phase change materials (PCMs), and are expected to achieve all-day anti-icing in various fields. Finally, the latest achievements in developing MPSS surfaces, showcasing their immense potential, are highlighted. Besides, the perspectives on the future development of MPSS surfaces are provided and the problems that need to be solved in their practical applications are proposed.
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Sorption-based atmospheric water harvesting (SAWH) is a promising approach for supplying water in off-grid arid regions. However, it is difficult to improve the SAWH efficiency because water undergoes multiple phase transformations, such as water vapor-water (desorption and condensation) in the desorption phase. To address this issue, an ultrahygroscopic temperature-responsive hydrogel nanofiber inspired by Tillandsia is developed, comprising poly N-isopropylacrylamide, poly N-dimethylacetamide, and carbon nanotubes and impregnated with lithium chloride (PCP@LiCl). The hydrophobicity of the nanofiber membrane is enhanced with increasing temperature, facilitating water separation from the hydrogel in liquid form. Moreover, PCP@LiCl exhibits unique kinetics at 25 °C and 15%-30% relative humidity, capable of adsorbing moisture to saturation within 2 h, and oozing liquid water within 5 min under sunlight. Through global potential modeling, it is demonstrated that PCP@LiCl has potential applications in arid and semiarid regions. This study provides new insights into the design of high-performance composites for solar-powered atmospheric water harvesting.
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Passive solar membrane distillation (MD) is an emerging technology to alleviate water scarcity. Recently, its performance has been enhanced by multistage design, though the gains are marginal due to constrained temperature and vapor pressure gradients across the device. This makes condenser cooling enhancement a questionable choice. We argue that condenser heating could suppress the marginal effect of multistage solar MD by unlocking the moisture transport limit in all distillation stages. Here, we propose a stage temperature boosting (STB) concept that directs low-temperature heat to the condensers in the last stages, enhancing moisture transport across all stages. Through STB in the last two stages with a heat flux of 250 W m-2, a stage-averaged distillation flux of 1.13 L m-2 h-1 S-1 was demonstrated using an 8-stage MD device under one-sun illumination. This represents an 88% enhancement over the state-of-the-art 10-stage solar MD devices. More notably, our analysis indicates that 16-stage STB-MD devices driven by solar energy and waste heat can effectively compete with existing photovoltaic reverse osmosis (PV-RO) systems, potentially elevating freshwater production with low-temperature heat sources.
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Atmospheric water harvesting (AWH) is a promising solution to the water shortage problem. Current sorption-based AWH (SAWH) systems seldom obtain both wide climatic adaptability and high energy efficiency due to the lack of thermodynamic optimization. To achieve the ideal harvesting circulation in SAWH systems, the "optimal harvesting window" (OHW) design based on thermodynamic analysis was first proposed and validated by our prototype. The "OHW" theory indicates the water production rate and energy efficiency could be improved by properly reducing the adsorption temperature. As the humidity increases, the optimal adsorption temperature should be closer to the dew point of the environment. Experimental results revealed that, loaded with 3 kg widely adopted silica gel, the daily water production could reach 5.76-17.64 L/d with ultrahigh energy efficiency of 0.46-1.5 L/kWh. This prototype could also achieve optimal performance in wide climatic conditions in terms of 13-35 °C and 18%-72% RH. Lastly, the performance of photovoltaic (PV)-driven SAWH was evaluated. Results showed that a 1 m2 PV panel could generate 0.66-2 L water per day in Shanghai throughout the year, the highest in opening literature. Notably, this work introduces a promising concept that can help achieve large-scale, ultra-fast, energy-efficient AWH worldwide.