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1.
Langmuir ; 40(32): 17049-17059, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39083646

RESUMEN

Reducing the contact time of droplet impacts on surfaces is crucial for various applications including corrosion prevention and anti-icing. This study aims to explore a novel strategy that greatly reduces contact time using a superhydrophobic mesh surface with multiple sets of mutually perpendicular ridges while minimizing the influence of the impacting location. The effects of the impact Weber numbers and ridge spacing on the characteristics of the impact dynamics and contact time are studied experimentally. The experimental results reveal that, for the droplet impact on mesh surfaces, ridges can segment the liquid film into independently multiple-retracting liquid subunits. The retracted subunits provide the upward driving force, which may promote the splashing or pancake bouncing of droplets. At this point, the contact time has a negligible sensitivity for the impacting position and is significantly reduced by up to 68%. Furthermore, the time, dynamic pressure, and energy criteria for triggering splashing and pancake bouncing are proposed theoretically. This work provides an understanding of the mechanism and the design guidelines for effectively reducing the contact time of the impacting droplet on superhydrophobic surfaces.

2.
Int J Mol Sci ; 25(14)2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39062997

RESUMEN

Idiopathic pulmonary fibrosis (IPF) is a long-term condition with an unidentified cause, and currently there are no specific treatment options available. Alveolar epithelial type II cells (AT2) constitute a heterogeneous population crucial for secreting and regenerative functions in the alveolus, essential for maintaining lung homeostasis. However, a comprehensive investigation into their cellular diversity, molecular features, and clinical implications is currently lacking. In this study, we conducted a comprehensive examination of single-cell RNA sequencing data from both normal and fibrotic lung tissues. We analyzed alterations in cellular composition between IPF and normal tissue and investigated differentially expressed genes across each cell population. This analysis revealed the presence of two distinct subpopulations of IPF-related alveolar epithelial type II cells (IR_AT2). Subsequently, three unique gene co-expression modules associated with the IR_AT2 subtype were identified through the use of hdWGCNA. Furthermore, we refined and identified IPF-related AT2-related gene (IARG) signatures using various machine learning algorithms. Our analysis demonstrated a significant association between high IARG scores in IPF patients and shorter survival times (p-value < 0.01). Additionally, we observed a negative correlation between the percent predicted diffusing capacity for lung carbon monoxide (% DLCO) and increased IARG scores (cor = -0.44, p-value < 0.05). The cross-validation findings demonstrated a high level of accuracy (AUC > 0.85, p-value < 0.01) in the prognostication of patients with IPF utilizing the identified IARG signatures. Our study has identified distinct molecular and biological features among AT2 subpopulations, specifically highlighting the unique characteristics of IPF-related AT2 cells. Importantly, our findings underscore the prognostic relevance of specific genes associated with IPF-related AT2 cells, offering valuable insights into the advancement of IPF.


Asunto(s)
Células Epiteliales Alveolares , Biomarcadores , Fibrosis Pulmonar Idiopática , Aprendizaje Automático , Análisis de la Célula Individual , Humanos , Fibrosis Pulmonar Idiopática/metabolismo , Fibrosis Pulmonar Idiopática/genética , Fibrosis Pulmonar Idiopática/diagnóstico , Fibrosis Pulmonar Idiopática/patología , Análisis de la Célula Individual/métodos , Células Epiteliales Alveolares/metabolismo , Células Epiteliales Alveolares/patología , Perfilación de la Expresión Génica , Transcriptoma , Femenino , Masculino , Pronóstico
3.
Langmuir ; 40(24): 12818-12827, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38842118

RESUMEN

The rebound dynamics of double droplets impacting an inclined superhydrophobic surface decorated with macro-ridges are investigated via lattice Boltzmann method (LBM) simulations. Four rebound regions are identified, that is, the no-coalescence-rebound (NCR), the partial-coalescence-rebound of the middle part bounces first (PCR-M), and the side part bounces first (PCR-S), as well as the complete-coalescence-rebound (CCR). The occurrence of the rebound regions strongly depends on the droplet arrangement, the center-to-center distance of the droplets, and the Weber number. Furthermore, the contact time is closely related to the rebound regions. The PCR-M region can significantly reduce the contact time because the energy dissipation in this region may decrease which can promote the rebound dynamic. Intriguingly, the contact time is also affected by the droplet arrangement; i.e., droplets arranged parallel to the ridge dramatically shorten the contact time since this arrangement increases the asymmetry of the liquid film. Therefore, for multidrop impact, the contact time can be effectively manipulated by changing the rebound region and the droplet arrangement. This work focuses on elucidating the wetting behaviors, rebound regions, and contact time of the multiple-droplet impacting an inclined superhydrophobic surface decorated with macro-ridges.

4.
Langmuir ; 40(20): 10759-10768, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38712734

RESUMEN

Bouncing dynamics of a trailing drop off-center impacting a leading drop with varying time intervals and Weber numbers are investigated experimentally. Whether the trailing drop impacts during the spreading or receding process of the leading drop is determined by the time interval. For a short time interval of 0.15 ≤ Δt* ≤ 0.66, the trailing drop impacts during the spreading of the leading drop, and the drops completely coalesce and rebound; for a large time interval of 0.66 < Δt* ≤ 2.21, the trailing drop impacts during the receding process, and the drops partially coalesce and rebound. Whether the trailing drop directly impacts the surface or the liquid film of the leading drop is determined by the Weber number. The trailing drop impacts the surface directly at moderate Weber numbers of 16.22 ≤ We ≤ 45.42, while it impacts the liquid film at large Weber numbers of 45.42 < We ≤ 64.88. Intriguingly, when the trailing drop impacts the surface directly or the receding liquid film, the contact time increases linearly with the time interval but independent of the Weber number; when the trailing drop impacts the spreading liquid film, the contact time suddenly increases, showing that the force of the liquid film of the leading drop inhibits the receding of the trailing drop. Finally, a theoretical model of the contact time for the drops is established, which is suitable for different impact scenarios of the successive off-center impact. This study provides a quantitative relationship to calculate the contact time of drops successively impacting a superhydrophobic surface, facilitating the design of anti-icing surfaces.

5.
ACS Appl Mater Interfaces ; 16(17): 21790-21798, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38627332

RESUMEN

This work develops a novel perovskite Sr2FeNi0.35Mo0.65O6-δ (SFN0.35M) simultaneously using as a fuel electrode and oxygen electrode in a reversible solid oxide cell (RSOC). SFN0.35M shows outstanding electrocatalytic activity for hydrogen oxidation, hydrogen evolution, oxygen reduction, and oxygen evolution. In situ exsolution and dissolution of Fe-Ni alloy nanoparticles in SFN0.35M is revealed. In a reducing atmosphere, SFN0.35M shows in situ exsolution of Fe-Ni alloy nanoparticles, and then the Fe-Ni alloy is reoxidized into SFN0.35M while converting into an oxidizing atmosphere. The polarization resistances of SFN0.35M electrode are 0.043 Ω cm2 in 20% O2-N2 and 0.064 Ω cm2 in H2 at 850 °C. Moreover, symmetric fuel cells using the SFN0.35M electrode achieves a maximum power density of 0.501 W cm-2 at 850 °C in H2 fuel, while the symmetric electrolysis cell has an electrolysis current density of 0.794 A cm-2 at 1.29 V in 90% H2O-10% H2 at 850 °C. It is the first time we demonstrate that the cell voltage of symmetrical cell at 0.5 A cm-2 in the fuel cell mode and -0.5 A cm-2 in the electrolysis cell mode can be fully recovered in 10 electrode alternating cycles and therefore demonstrate the possibility that SFN0.35M can be used in a fully symmetric RSOC stack with electrode alternating functions.

6.
Langmuir ; 40(6): 3248-3259, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38298055

RESUMEN

Coalescence-induced jumping has promised a substantial reduction in the droplet detachment size and consequently shows great potential for heat-transfer enhancement in dropwise condensation. In this work, using molecular dynamics simulations, the evolution dynamics of the liquid bridge and the jumping velocity during coalescence-induced nanodroplet jumping under a perpendicular electric field are studied for the first time to further promote jumping. It is found that using a constant electric field, the jumping performance at the small intensity is weakened owing to the continuously decreased interfacial tension. There is a critical intensity above which the electric field can considerably enhance the stretching effect with a stronger liquid-bridge impact and, hence, improve the jumping performance. For canceling the inhibition effect of the interfacial tension under the condition of the weak electric field, a square-pulsed electric field with a paused electrical effect at the expansion stage of the liquid bridge is proposed and presents an efficient nanodroplet jumping even using the weak electric field.

7.
ACS Omega ; 9(1): 509-519, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38222531

RESUMEN

Adsorption heat conversion systems can provide heating and cooling across time and space in a more environmentally friendly way. Porous materials are potential candidates for water-based adsorption thermal conversion, in which a metal-organic framework (MOF) has a larger specific surface area and porosity than other porous matrices. However, many MOFs with high saturated adsorption capacity have great deficiencies in performance at low water vapor partial pressure, which hinder their application in adsorption thermal conversion. To improve the water vapor adsorption performance of MIL-101 (Cr), different contents of magnesium chloride, lithium chloride, and lanthanum chloride are mixed into MIL-101 (Cr) by an impregnation method. The properties and structures of the materials are characterized by XRD, SEM, nitrogen adsorption tests, water vapor adsorption tests, TG, FTIR, and so on. The results show that the saturated water vapor adsorption capacity of the sample impregnated with salt increases by 1.5-2.3 times, up to 2.24 g/g, compared with that of the unimpregnated sample. When the partial pressure of water vapor is 0.3, the adsorption capacity increases by 5.3-7.5 times and reaches 0.68 g/g at most. The maximum heat storage density of impregnated samples can be increased by 866 J/g. Impregnated MgCl2 can greatly improve the adsorption and thermal conversion performance of MOF, and impregnated MgCl2 and the proper amount of LiCl can further improve the performance of the material system. Our experiments show that the composite impregnation of magnesium chloride and the proper amount of lithium chloride can improve the application performance of the MOF materials in the adsorption thermal conversion process.

8.
Int Urol Nephrol ; 56(1): 191-198, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37195572

RESUMEN

BACKGROUND: Cardiovascular disease (CVD) is an important cause of morbidity and mortality in peritoneal dialysis (PD) patients. Cardiovascular calcification (CVC) is highly prevalent in PD patients and could predict their cardiovascular mortality. Soluble urokinase plasminogen activator receptor (suPAR) is closely associated with coronary artery calcification in hemodialysis patients and is an important predictor of CVD. However, the role of suPAR in PD patients is poorly understood. We investigated the relationship between serum suPAR and CVC in PD patients. METHODS: Abdominal aortic calcification (AAC) was assessed by lateral lumbar radiography, coronary artery calcification (CAC) by multi-slice computed tomography, and cardiac valvular calcification (ValvC) by echocardiography. CVC was defined as confirmed presence of calcification in one site (AAC, CAC, or ValvC). Patients were divided into CVC group and non-CVC group. Demographic characteristics, biochemical variables, comorbidities, PD regimen, serum suPAR, and medication were compared between the two groups. Logistic regression was conducted to determine association between serum suPAR and presence of CVC. The receiver-operator curve (ROC) was plotted to calculate the area under the curve (AUC) for suPAR to identify CVC and ValvC. RESULTS: Of 226 PD patients, 111 (49.1%) had AAC, 155 (68.6%) had CAC, and 26 (11.5%) had ValvC. There were significant differences in age, BMI, diabetes, white blood cell, phosphorus, hs-CRP, suPAR, time on dialysis, total volume of dialysate, ultrafiltration, volume of urine, and Kt/V between CVC and non-CVC group. Serum suPAR was associated with CVC by multivariate logistic regression analysis in PD patients, especially in elderly patients. The levels of serum suPAR were closely related to the degree of AAC, CAC, and ValvC in PD patients. The incidence of CVC was higher in patients with higher levels of suPAR. The ROC curve showed that serum suPAR had a predictive value for CVC (AUC = 0.651), especially for ValvC (AUC = 0.828). CONCLUSION: Cardiovascular calcification is prevalent in PD patients. High levels of serum suPAR are associated with cardiovascular calcification in PD patients, especially in elderly patients.


Asunto(s)
Calcinosis , Enfermedades Cardiovasculares , Enfermedad de la Arteria Coronaria , Diálisis Peritoneal , Humanos , Biomarcadores , Enfermedad de la Arteria Coronaria/epidemiología , Diálisis Peritoneal/efectos adversos , Receptores del Activador de Plasminógeno Tipo Uroquinasa , Factores de Riesgo
9.
Nutr Metab Cardiovasc Dis ; 34(3): 706-717, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37996370

RESUMEN

BACKGROUND AND AIMS: Coronary artery disease (CAD), heart failure (HF), and ischemic heart disease (IHD) are three common cardiovascular diseases that are closely associated with metabolic activity. The global incidence and prevalence of these conditions are on the rise, primarily due to unhealthy lifestyles, aging populations, and the increasing prevalence of obesity and diabetes. Excessive screen time has emerged as a potential risk factor for various adverse health outcomes, although limited research has explored its relationship with cardiovascular disease outcomes. METHODS AND RESULTS: A Mendelian randomization (MR) study was conducted, employing exposure-associated genetic variants as instrumental variables to explore the causal relationship between screen time use and cardiovascular disease outcomes. Single nucleotide polymorphisms (SNPs) were utilized as pooled data for the genetic variable instrument, investigating the association between screen use duration and three types of cardiovascular diseases: coronary artery disease (CAD), heart failure (HF), and ischemic heart disease (IHD). Through the MR analysis, it was revealed that the use of mobile phones and TV screens exhibited a significant causal association with the occurrence of CAD, heart failure, and IHD. However, no significant association was observed between the use of computers and these three types of cardiovascular diseases. CONCLUSION: Our study suggests that excessive screen time use is associated with the development of cardiovascular disease. However, it should be noted that the consequences of screen time can vary depending on the reasons and purposes for its use. Implementing reasonable control over screen time, particularly for entertainment purposes, holds promise as a potential approach to mitigating cardiovascular disease.


Asunto(s)
Enfermedades Cardiovasculares , Enfermedad de la Arteria Coronaria , Insuficiencia Cardíaca , Isquemia Miocárdica , Humanos , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/genética , Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/epidemiología , Enfermedad de la Arteria Coronaria/genética , Análisis de la Aleatorización Mendeliana/métodos , Tiempo de Pantalla , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/epidemiología , Isquemia Miocárdica/genética , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/epidemiología , Insuficiencia Cardíaca/genética
10.
Pathol Res Pract ; 253: 155064, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38160481

RESUMEN

Cancer remains the primary cause of mortality in developed nations. Although localized tumors can be effectively addressed through surgery, radiotherapy, and other targeted methods, drug efficacy often wanes in the context of metastatic diseases. As a result, significant efforts are being made to develop drugs capable of not only inhibiting tumor growth but also impeding the metastasis of malignant tumors, with a focus on hindering their migration to adjacent organs. Cancer stem cells metastasize via blood and lymphatic vessels, exhibiting a high mutation rate, significant variability, and a predisposition to drug resistance. In contrast, endothelial cells, being less prone to mutation, are less likely to give rise to drug-resistant clones. Furthermore, the direct contact of circulating anti-angiogenic drugs with vascular endothelial cells expedites their therapeutic impact. Hence, anti-angiogenesis targeted therapy assumes a pivotal role in cancer treatment. This paper provides a succinct overview of the molecular mechanisms governing the interaction between cancer stem cells and angiogenesis.


Asunto(s)
Neoplasias , Neovascularización Patológica , Humanos , Neovascularización Patológica/genética , Células Endoteliales/patología , Angiogénesis , Neoplasias/genética , Células Madre Neoplásicas/patología
11.
Langmuir ; 39(50): 18644-18653, 2023 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-38051278

RESUMEN

This study investigates whether adding ridges to a superhydrophobic cylindrical surface can reduce contact times compared to those of ridged flat or cylindrical surfaces, inspired by the shortened contact time achieved by adding ridges to flat surfaces. The study focuses on studying azimuthal ridges on the cylinder through experimentation, emphasizing the impact dynamics and contact time characteristics under varying We (Weber number) and D* (dimensionless droplet diameter). Within the ultralow Weber number range (ULWR), low Weber number range (LWR), and medium Weber number range (MWR), the contact time is longer than on ridged flat surfaces. In the high Weber number range (HWR), the opposite is observed: increased inertial forces lead to the rupture of the liquid film above the ridges due to Rayleigh-Plateau instability. As a result, the primary droplet splits into two sections with curvature effects promoting its recoiling and rebounding. This study introduces a criterion, defined as C = We/D*, and finds that when C exceeds 2.42, not only is the contact time shorter than on ridged flat or cylindrical surfaces, but it also further decreases with an increase in We or a decrease in D*. The contact time characteristics observed in the HWR offer potential applications in areas such as anti-icing.

12.
Langmuir ; 39(51): 19037-19047, 2023 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-38096493

RESUMEN

Reducing the contact time during the droplet impact on the surface is crucial for anti-icing, self-cleaning, and heat transfer optimization applications. This study aims to minimize the contact time by modifying the surface curvature to create an asymmetric impact process. Our experiments showed that the increase in Weber numbers (We) and the decrease in the ratio of surface diameter to droplet diameter (D*) intensify the asymmetry of the impact process, yielding four distinct rebound modes. Low asymmetry observes the liquid retract toward the central point (Rebound Modes 1 and 2), whereas high asymmetry yields a wing-like rebound (Rebound Modes 3 and 4). In Rebound Mode 1, increased asymmetry would lead to more extended contact due to the prolonged waiting period. Conversely, the reduction in contact time in Rebound Mode 2 occurs due to increased asymmetry with no waiting period. For Rebound Modes 3 and 4, the retraction time could be divided into three stages, generated by two liquid detachment modes from the surface. Analysis reveals that an increased asymmetry would reduce the retraction time during the first stage but prolong it during the third stage, with no significant effects on the second. Four correlations, each pertaining to a distinct impact mode, are proposed based on these analyses to describe the contact time concerning We and D* for droplets impacting a superhydrophobic cylindrical surface.

13.
Behav Sci (Basel) ; 13(11)2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37998687

RESUMEN

Community group buying is a new retail model with broad development prospects. The community group buying model in China has brought obvious social and economic benefits. However, the continuous usage rate on some community group buying platforms is relatively low. Consumers' continuous usage intentions are closely related to the sustainable development of community group buying platforms. Therefore, this study integrates the information system success model (D&M model) and the expanded technology acceptance model (TAM) to construct a research model that explores the factors influencing consumers' continuous usage intentions from both the platform's and consumers' perspectives. The survey data involving 418 respondents who used community group buying platforms were developed and analyzed for structural equation model (SEM) testing. The results show the following: (1) Perceived usefulness, perceived ease of use, service quality, perceived trust, expectation confirmation, and subjective norms significantly affect continuous usage intention. (2) Subjective norms are significantly related to continuous usage intention. Perceived usefulness, perceived ease of use, service quality, perceived trust, and expectation confirmation indirectly affect continuous usage intention through user satisfaction. This research provides a new perspective for the theoretical research of community group buying and helps to promote the sustainable development of community group buying platforms in management practice.

14.
Langmuir ; 39(45): 16023-16034, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37916520

RESUMEN

Extensive research has shown that a superhydrophobic cylindrical substrate could lead to a noncircumferential symmetry of an impacting droplet, reducing the contact time accordingly. It is of practical significance in applications, such as anti-icing, anticorrosion, and antifogging. However, few accounts have adequately addressed the off-centered impact of the droplet, despite it being more common in practice. This work investigates the dynamic behavior of a droplet off-centered impacting a superhydrophobic cylinder via the lattice Boltzmann method. The effect of the off-centered distance is primarily discussed for droplets taking various Weber numbers and cylinder sizes. The results show that the imposition of an off-center distance can further disrupt the droplet symmetry during the impact. As the off-center distance increases, the droplet movement is gradually tilted toward the offset side until it tangentially passes the cylinder side, resulting in a direct dripping mode. The dynamic features, focusing mainly on maximum spreading in the axial direction and contact time, are specifically explored. A quantitative model of the maximum spreading factor is proposed based on the equivalent transformation from the off-center impact into oblique hitting, considering the full range of off-centered distance. A preliminary contact time model is established for droplet off-centered impacting superhydrophobic cylinders by substituting the maximum spreading and the effective velocity of the liquid moving. This work aims to make an original contribution to the fundamental knowledge of droplet impact and could be of value for related applications.

15.
Langmuir ; 39(49): 18052-18059, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38010376

RESUMEN

We investigated the microscale electrohydrodynamic (EHD) conduction pumps in a wide range of working regimes, from the saturation regime to the ohmic regime. We showed that the existing macro- and microscale theoretical models could not accurately predict the electric force of microscale EHD conduction pumps, especially for the cases of a strong diffusion effect. We clarified that the failure is caused by a rough estimate of the heterocharge layer thickness. We revised the expression of heterocharge layer thickness by considering the diffusion effect and developed a new theoretical model for the microscale EHD conduction pumps based on the revised expression of heterocharge layer thickness. The results showed that our model can accurately predict the dimensionless electric force of the microscale EHD conduction pumps even for the cases of a strong diffusion effect. Furthermore, we developed a working regime map of microscale EHD conduction pumps and found that the microscale EHD conduction pumps more easily fall into the saturation regime compared with the macroscale EHD conduction pumps due to the enhanced diffusion effect; in other words, the microscale EHD conduction pumps have a wider saturation regime. We showed that the conduction number C0 could not distinguish the working regime of the microscale EHD conduction pumps because it does not take the diffusion effect into account. By employing the revised expression of heterocharge layer thickness, we proposed a new dimensionless number, C0D to distinguish the working regimes of microscale EHD conduction pumps.

16.
Open Life Sci ; 18(1): 20220710, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37671091

RESUMEN

The process of aging is marked by a gradual deterioration in the physiological functions and functional reserves of various tissues and organs, leading to an increased susceptibility to diseases and even death. Aging manifests in a tissue- and organ-specific manner, and is characterized by varying rates and direct and indirect interactions among different tissues and organs. Cardiovascular disease (CVD) is the leading cause of death globally, with older adults (aged >70 years) accounting for approximately two-thirds of CVD-related deaths. The prevalence of CVD increases exponentially with an individual's age. Aging is a critical independent risk factor for the development of CVD. AMP-activated protein kinase (AMPK) activation exerts cardioprotective effects in the heart and restores cellular metabolic functions by modulating gene expression and regulating protein levels through its interaction with multiple target proteins. Additionally, AMPK enhances mitochondrial function and cellular energy status by facilitating the utilization of energy substrates. This review focuses on the role of AMPK in the process of cardiac aging and maintaining normal metabolic levels and redox homeostasis in the heart, particularly in the presence of oxidative stress and the invasion of inflammatory factors.

17.
Langmuir ; 39(37): 13371-13385, 2023 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-37675482

RESUMEN

Profiting from their slippery nature, lubricant-infused porous surfaces endow with droplets excellent mobility and consequently promise remarkable heat transfer improvement for dropwise condensation. To be a four-phase wetting system, the droplet wettability configurations and the corresponding dynamic characteristics on lubricant-infused porous surfaces are closely related to many factors, such as multiple interfacial interactions, surface features, and lubricant thickness, which keeps a long-standing challenge to promulgate the underlying physics. In this work, thermodynamically theoretical analysis and three-dimensional molecular dynamics simulations with the coarse-grained water and hexane models are carried out to explore droplet wettability and mobility on lubricant-infused porous surfaces. Combined with accessible theoretical criteria, phase diagrams of droplet configurations are constructed with a comprehensive consideration of interfacial interactions, surface structures, and lubricant thickness. Subsequently, droplet sliding and coalescence dynamics are quantitatively defined under different configurations. Finally, in terms of the promotion of dropwise condensation, a non-cloaking configuration with the encapsulated state underneath the droplet is recommended to achieve high droplet mobility owing to the low viscous drag of the lubricant and the eliminated pinning effect of the contact line. On the basis of the low oil-water and water-solid interactions, a stable lubricant layer with a relatively low thickness is suggested to construct slippery surfaces.

18.
Langmuir ; 39(33): 11760-11768, 2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37555811

RESUMEN

Using molecular dynamics simulations, we investigate the air hole formation of water nanodroplets impacting hydrophilic to hydrophobic surfaces in the range of static contact angles from 30° to 140° with different initial surface temperatures ranging from 300 to 1000 K. We show that the hole dynamics of nanodroplets are different from those observed in millimeter-sized droplets. The hole formation can be observed on smooth surfaces for nanodroplets; however, it only occurs on nonsmooth surfaces for millimeter-sized droplets. We clarify that the hole formation of nanodroplets is triggered by a nucleated vapor bubble due to thermodynamic instability, whereas it is initiated by air bubble entrapment during impact due to hydrodynamic instability for millimeter-sized droplets. The hole formation of nanodroplets relies heavily on the surface temperature and surface wettability, because the nucleated vapor bubble more easily occurs and grows on the surface with high initial temperatures and hydrophobic surfaces. Based on the thermal stability analysis, a criterion is developed to predict the hole formation of nanodroplets, which verifies the dependence of hole formation on the surface temperature and wettability. Furthermore, we show that the ring-bouncing of nanodroplets is triggered by the nucleated vapor bubble. We clarify the reasons for the reduced contact time of nanodroplets caused by the ring-bouncing.

19.
Sensors (Basel) ; 23(13)2023 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-37448033

RESUMEN

We present a straightforward approach to develop a high-detectivity silicon (Si) sub-bandgap near-infrared (NIR) photodetector (PD) based on textured Si/Au nanoparticle (NP) Schottky junctions coated with graphene film. This is a photovoltaic-type PD that operates at 0 V bias. The texturing of Si is to trap light for NIR absorption enhancement, and Schottky junctions facilitate sub-bandgap NIR absorption and internal photoemission. Both Au NPs and the texturing of Si were made in self-organized processes. Graphene offers additional pathways for hot electron transport and to increase photocurrent. Under 1319 nm illumination at room temperature, a responsivity of 3.9 mA/W and detectivity of 7.2 × 1010 cm × (Hz)1/2/W were obtained. Additionally, at -60 °C, the detectivity increased to 1.5 × 1011 cm × (Hz)1/2/W, with the dark current density reduced and responsivity unchanged. The result of this work demonstrates a facile method to create high-performance Si sub-bandgap NIR PDs for promising applications at ambient temperatures.


Asunto(s)
Grafito , Nanopartículas del Metal , Oro , Silicio , Películas Cinematográficas
20.
J Colloid Interface Sci ; 650(Pt A): 490-497, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37421751

RESUMEN

Supercapacitor electrodes often suffer from the low mass loading of active substances and the unsatisfactory ion/charge transport features due to the use of various additives. Exploring high mass loading and additive-free electrodes is of huge significance to develop advanced supercapacitors with commercial application prospects, which still remains challenging. Herein, high mass loading CoFe-prussian blue analogue (CoFe-PBA) electrodes are developed by a facile co-precipitation method using activated carbon cloth (ACC) as the flexible substrate. The homogeneous nanocube structure, large specific surface area (143.9 m2 g-1) and appropriate pore size distribution (3.4 nm) of the CoFe-PBA endow the as-prepared CoFe-PBA/ACC electrodes with low resistance and appealing ion diffusion characteristics. Typically, the high areal capacitance (1155.0 mF cm-2 at 0.5 mA cm-2) is obtained for high mass loading CoFe-PBA/ACC electrodes (9.7 mg cm-2). Furthermore, symmetrical flexible supercapacitors (FSCs) are constructed using CoFe-PBA/ACC electrodes and Na2SO4/polyving alcohol (Na2SO4/PVA) gel electrolyte, achieving superior stability (85.6% capacitance retention after 5,000 cycles), maximum energy density of 33.8 µWh cm-2 at 200.0 µW cm-2 and promising mechanical flexibility. This work is expected to offer inspirations for the development of high mass loading and additive-free electrodes for FSCs.

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