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1.
Bioengineering (Basel) ; 11(5)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38790367

RESUMO

BACKGROUND: This research investigates the biomechanical impact of the split-step technique on forehand and backhand lunges in badminton, aiming to enhance players' on-court movement efficiency. Despite the importance of agile positioning in badminton, the specific contributions of the split-step to the biomechanical impact of lunging footwork still need to be determined. METHODS: This study examined the lower limb kinematics and ground reaction forces of 18 male badminton players performing forehand and backhand lunges. Data were collected using the VICON motion capture system and Kistler force platforms. Variability in biomechanical characteristics was assessed using paired-sample t-tests and Statistical Parametric Mapping 1D (SPM1D). RESULTS: The study demonstrates that the split-step technique in badminton lunges significantly affects lower limb biomechanics. During forehand lunges, the split-step increases hip abduction and rotation while decreasing knee flexion at foot contact. In backhand lunges, it increases knee rotation and decreases ankle rotation. Additionally, the split-step enhances the loading rate of the initial ground reaction force peak and narrows the time gap between the first two peaks. CONCLUSIONS: These findings underscore the split-step's potential in optimizing lunging techniques, improving performance and reducing injury risks in badminton athletes.

2.
Inorg Chem ; 63(6): 3099-3106, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38299496

RESUMO

Electrochemical conversion of nitrogen into ammonia at ambient conditions as a sustainable approach has gained significant attention, but it is still extremely challenging to simultaneously obtain a high faradaic efficiency (FE) and NH3 yield. In this work, the interstitial boron-doped porous Pd nanotubes (B-Pd PNTs) are constructed by combining the self-template reduction method with boron doping. Benefiting from distinctive one-dimensional porous nanotube architectonics and the incorporation of the interstitial B atoms, the resulting B-Pd PNTs exhibit high NH3 yield (18.36 µg h-1 mgcat.-1) and FE (21.95%) in neutral conditions, outperforming the Pd/PdO PNTs (10.4 µg h-1 mgcat.-1 and 8.47%). The present study provides an attractive method to enhance the efficiency of the electroreduction of nitrogen into ammonia by incorporating interstitial boron into porous Pd-based catalysts.

3.
ArXiv ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38351926

RESUMO

Despite advancements in artificial intelligence, object recognition models still lag behind in emulating visual information processing in human brains. Recent studies have highlighted the potential of using neural data to mimic brain processing; however, these often rely on invasive neural recordings from non-human subjects, leaving a critical gap in understanding human visual perception. Addressing this gap, we present, for the first time, 'Re(presentational)Al(ignment)net', a vision model aligned with human brain activity based on non-invasive EEG, demonstrating a significantly higher similarity to human brain representations. Our innovative image-to-brain multi-layer encoding framework advances human neural alignment by optimizing multiple model layers and enabling the model to efficiently learn and mimic human brain's visual representational patterns across object categories and different modalities. Our findings suggest that ReAlnet represents a breakthrough in bridging the gap between artificial and human vision, and paving the way for more brain-like artificial intelligence systems.

4.
J Hazard Mater ; 467: 133608, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38335613

RESUMO

This study investigated the pollution of perfluorinated compounds (PFCs) in sediments from the main stream of the Yangtze River, the longest river in Asia. Totally, 13 of 15 PFASs were detected in the sediments and the total concentrations ranged from 0.058 ng/g to 0.89 ng/g dry weight (dw), with dominant contaminants by perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA). Concentrations of PFASs in the downstream were higher than those of upstream and midstream. Four main sources were analysed using the Unmix model, textile treatments and food packaging dominantly accounted for approximately half of the total sources, followed by metal electroplating (26.8%), fluoropolymer products (16.3%) and fluororesin coatings (7.4%). Total organic carbon (TOC), total nitrogen (TN) and grain size had significant correlation with the concentration of PFASs in sediments, indicating that the physical and chemical parameters could directly affect the adsorption process of PFASs. In addition, anthropogenic factors such as urbanization rate and per capita GDP also had a direct impact on the distribution of PFASs. Environmental risk assessment showed that PFOS posed low to medium risks to the Yangtze River, indicating that sustained attentions were needed.

5.
Rev. psicol. deport ; 33(1): 13-20, 2024. ilus, tab, graf
Artigo em Inglês | IBECS | ID: ibc-231711

RESUMO

To encourage physical education teachers to prioritise students' physical education as the central focus of interaction, foster a shift towards student-centred teaching, enhance enthusiasm for college physical education courses, and integrate moral education principles into the physical education curriculum. This study examined the impact of teacher-student interaction on students' self-cultivation in ideological and political education within the physical education curriculum at the college level through the construction of an equal education model. The data was entered into the system using SPSS 23.0 and Amos 26.0 statistical software to assess the reliability, validity, and research hypothesis of the model. The impact of physical exercise, personal exercise, sports organisations, sports events, and teacher consultation were found to be 0.944%, 0.93%, 0.897%, and 0.935%, respectively. Teacher-student interaction is crucial in physical education (PE) classes, particularly for sports education and promoting growth. The presence of sports facilities and equipment significantly influences teacher-student interaction. Therefore, it is essential to enhance the development of PE courses, improve the availability of physical education resources, update teaching approaches, implement innovative models of PE classes, and enhance students' sense of achievement to facilitate effective teacher-student interaction.(AU)


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Estudantes , Educação Física e Treinamento , Psicologia do Esporte , Exercício Físico , Docentes , Influência dos Pares
6.
Rev. psicol. deport ; 32(4): 322-330, Oct 15, 2023. tab
Artigo em Inglês | IBECS | ID: ibc-228875

RESUMO

This study uses narrative and positive psychology as its theoretical foundations to investigate the impact of sports activities on young people's mental health. Class 1 and Class 2 students of the Department of Economics and Management in the Modern College of Arts and Sciences of a normal university, as well as some front-line Physical Education (PE) instructors and ideological and political teachers of a normal university, were surveyed. This study utilized a questionnaire to collect information from respondents. Smart PLS 4.0 is used to analyze the data for this study. This study found that, from the perspective of compassionate ethics and in the context of the COVID-19 pandemic, physical activity can promote the mental health of adolescents, most notably by reducing anxiety, stress, depression, and feelings of isolation. This study determined that physical activity promotes the healthy growth of adolescent narrative psychology. Furthermore, physical activity significantly impacts adolescents' mental health, which can reduce adolescent ennui, boredom, and the risk of depression. Moreover, it can reduce stress, alleviate anxiety, and enhance adolescents' sleep quality. In addition, it can improve adolescents' mental health, cognitive health, thinking, learning, and general well-being.(AU)


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Esportes , Estudantes/psicologia , Exercício Físico , Psicologia do Adolescente , Psicologia do Esporte , Saúde Mental
7.
Sci Total Environ ; 902: 166058, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37553051

RESUMO

Phthalate esters (PAEs) are the most ubiquitous and highly used plasticizers in plastic products globally, yet studies on the spatial variation, risks, and their correlation with microplastics (MPs) are limited, particularly throughout the Yangtze River (the largest river in China/Asia). Therefore, this study investigated for the first time the PAEs pollution characteristics throughout the Yangtze River sediments, studied the environmental factors linked to the distribution of PAEs, and explored their potential as chemical indicators for interpreting pollution patterns of MPs. Totally 14 out of 16 PAEs were detected in sediments, with total concentrations ranging from 84.67 ng/g to 274.0 ng/g (mean: 163.5 ng/g), dominated by Bis(2-ethylhexyl) phthalate (DEHP), Di-n-butyl phthalate (DBP), and Di-isobutyl phthalate (DIBP), with contributions of 38.9 %, 31.8 %, and 20.8 %, respectively. Spatial distribution of PAEs did not indicate significant differences, which may be related to anthropogenic activities (i.e., emission intensity), runoff, and sediment physicochemical properties (i.e., TOC and TN), with TOC and TN being potential predictors of PAEs. The quantitative relationships (p < 0.001) between DEHP/∑16PAEs ratio and MPs (both individual and total MPs) were found in sediments, which suggested that DEHP could be potentially used as an indicator for MPs. DEHP, DIBP, and DBP posed high risks, accounting for 100 %, 68.4 %, and 10.5 % of the monitoring sites, respectively. Further work is necessary to better understand the relationship between DEHP/∑16PAEs and MPs in the environment and to take corresponding management and control measures for these pollutants.

8.
Sci Total Environ ; 885: 163772, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37149176

RESUMO

This work is the first time to investigate the annual flux, spatiotemporal changes and sources of PCBs and PBDEs in water and sediment from the middle reach of Yangtze River (Wuhan, China), which was particularly based on the monthly monitoring data in a one-year-round study. The concentrations of PCBs and PBDEs in water were

Assuntos
Bifenilos Policlorados , Poluentes Químicos da Água , Bifenilos Policlorados/análise , Rios , Éteres Difenil Halogenados/análise , Monitoramento Ambiental/métodos , Ecossistema , Poluentes Químicos da Água/análise , Sedimentos Geológicos/análise , China , Água/análise
9.
Biomater Sci ; 11(8): 2898-2911, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-36883448

RESUMO

Since nanozymes were proposed, their applications have become more and more extensive. As a research hotspot in recent years, MoS2 also shows many enzyme-like properties. However, as a novel peroxidase, MoS2 has the disadvantage of a low maximum reaction rate. In this study, the MoS2/PDA@Cu nanozyme was synthesized by a wet chemical method. The modification of PDA on the surface of MoS2 achieved the uniform growth of small-sized Cu Nps. The obtained MoS2/PDA@Cu nanozyme displayed excellent peroxidase-like activity and antibacterial properties. The minimum inhibitory concentration (MIC) of the MoS2/PDA@Cu nanozyme against S. aureus reached 25 µg mL-1. Furthermore, it showed a more pronounced inhibitory effect on bacterial growth with the addition of H2O2. The maximum reaction rate (Vmax) of the MoS2/PDA@Cu nanozyme is 29.33 × 10-8 M s-1, which is significantly higher as compared to that of HRP. It also exhibited excellent biocompatibility, hemocompatibility and potential anticancer properties. When the concentration of the nanozyme was 160 µg mL-1, the viabilities of 4T1 cells and Hep G2 cells were 45.07% and 32.35%, respectively. This work indicates that surface regulation and electronic transmission control are good strategies for improving peroxidase-like activity.


Assuntos
Molibdênio , Peroxidase , Molibdênio/química , Staphylococcus aureus , Peróxido de Hidrogênio/farmacologia , Peroxidases/farmacologia , Corantes/farmacologia , Antibacterianos/química
10.
Environ Geochem Health ; 45(10): 7405-7424, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36788152

RESUMO

This study investigated the sources, contamination and ecological risks of polycyclic aromatic hydrocarbons (PAHs) based on their spatiotemporal distribution in aquatic environment in the Wuhan section of the Yangtze River (WYR). The fugacity ratio evaluation indicated that sediment was secondary release sources of two- and three-ring PAHs and sinks of four- and five-ring PAHs. The total concentrations of PAHs (Σ16PAHs) ranged from 2.51 to 102.5 ng/L in water with the dominant contribution of 47.8% by two-ring PAHs. Σ16PAHs in sediments varied from 5.90 to 2926 ng/g with the contribution of 35.4% by four-ring PAHs. The higher levels of PAHs occurred around developed industrial areas during the wet season, which was related to local industrial emissions and influenced by rainfall/runoff. Annual flux of Σ16PAHs was estimated of 28.77 t. The PMF model analysis revealed that petroleum and industrial emissions were the dominant sources in water accounting for 58.5% of the total pollution, although traffic emission was the main source for sediment accounting for 44.6%. Risk assessments showed that PAHs in water were at low risks, whereas about 44% of the sediments were identified as medium risks. Therefore, energy structure adjustment and further implement of regulation and monitoring are necessary to reduce PAH emissions.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Hidrocarbonetos Policíclicos Aromáticos/análise , Rios/química , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Sedimentos Geológicos/química , China
11.
Environ Toxicol Chem ; 42(3): 605-619, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36582153

RESUMO

To our knowledge, ours is the first study to investigate the annual fluxes, environmental fate, and ecological risks of five categories of antibiotics from the Wuhan section of the Yangtze River (China). All the 24 antibiotics we tested for were detected in water, with total concentrations of 17.11-867.2 ng/L (mean: 63.69 ng/L), and 19 antibiotics were detected in sediment, at 0.02-287.7 ng/g (mean: 16.54 ng/g). Sulfonamides, amphenicols, and macrolides were the three most prominent antibiotic classes in water, and fluoroquinolones were the most prominent in sediment. Farming activities (animal husbandry and aquaculture) are proposed as the largest contributors to antibiotic pollution in the Wuhan section of the Yangtze River according to the Unmix model, followed by municipal wastewater and mixed sources. Higher pollution levels were observed downstream (combined discharge of these sources). Monthly monitoring data (12 months) were used to estimate antibiotic annual fluxes, with 101.5 t (uncertainty: 5.6%) in the Wuhan section of the Yangtze River. Risk assessments showed that erythromycin, clarithromycin, and azithromycin posed medium and high ecological risks and were found in 9%-35% and 1.8%-3.7% of all water samples, respectively; enrofloxacin, clarithromycin, azithromycin, florfenicol, and thiamphenicol posed medium resistance risks in 1.9%-16.7% of waters in the Wuhan section of the Yangtze River. Our results have filled data gaps on antibiotic sources, annual fluxes, and resistance risk in the Wuhan section of the Yangtze River and demonstrated the importance of further management of antibiotic use in the studied areas. Environ Toxicol Chem 2023;42:605-619. © 2022 SETAC.


Assuntos
Antibacterianos , Poluentes Químicos da Água , Animais , Antibacterianos/análise , Poluentes Químicos da Água/análise , Azitromicina , Claritromicina , Monitoramento Ambiental , China , Medição de Risco , Água
12.
Front Psychol ; 14: 1275666, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38288363

RESUMO

Traditional research on firm performance has predominantly emphasized the role of key departments, often underestimating the potential contributions of non-core departments. This study redresses this oversight by investigating the impact of non-core departments on firm performance. Utilizing a comprehensive 20-year dataset from Chinese A-listed firms and employing the endogenous growth model, we scrutinize the influence of non-core departments on enterprise productivity and organizational growth. Our findings underscore that non-core departments significantly enhance firm performance. Furthermore, we observe a negative coefficient of the interaction term, implying the presence of diminishing returns to scale when amalgamating department diversity with firm knowledge. This suggests that while both department diversity and firm knowledge independently contribute positively to firm performance, their conjoined effect does not necessarily induce a proportionally amplified impact. Moreover, we found that factors such as the company's equity structure, market environment, and the age and education level of executives may moderate the impact of departmental diversity on firm performance. This study enriches the literature by spotlighting the potential of non-core departments in propelling firm success and underlines the imperative for strategies that cultivate interdepartmental collaboration. The implications of these findings propose that firms can leverage the potential of non-core departments for sustainable growth, offering a fresh perspective for future research in organizational development.

13.
J Nanobiotechnology ; 20(1): 467, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329436

RESUMO

In 2020, nearly 20 million peoples got cancer and nearly 10 million peoples died of cancer, indicating the cancer remains a great threat to human health and life. New therapies are still in urgent demand. We here develop a novel cancer therapy named Ferroptosis ASsassinates Tumor (FAST) by combining iron oxide nanoparticles with cancer-selective knockdown of seven key ferroptosis-resistant genes (FPN, LCN2, FTH1, FSP1, GPX4, SLC7A11, NRF2). We found that FAST had notable anti-tumor activity in a variety of cancer cells but little effect on normal cells. Especially, FAST eradicated three different types of tumors (leukemia, colon cancer, and lung metastatic melanoma) from over 50% of cancer mice, making the mice survive up to 250 days without tumor relapse. FAST also significantly inhibited and prevented the growth of spontaneous breast cancer and improved survival in mice. FAST showed high pan anti-tumor efficacy, high cancer specificity, and in vivo safety. FAST defines a new form of advanced nanomaterials, advanced combinatorial nanomaterials, by combining two kinds of nanomaterials, a chemical nanomaterial (iron oxide nanoparticles) and a biochemical nanomaterial (adeno-associated virus), which successfully turns a general iron nanomaterial into an unprecedented assassin to cancer.


Assuntos
Neoplasias da Mama , Ferroptose , Neoplasias Pulmonares , Humanos , Camundongos , Animais , Feminino , Linhagem Celular Tumoral , Ferro
14.
Environ Sci Technol ; 56(20): 14439-14451, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36169941

RESUMO

This study conducted the first extensive and comprehensive investigation of the whole-scale sedimentary antibiotic concentration, possible drivers, environmental fate, and potential ecological risks in the Yangtze River. Totally, 20 antibiotics were detected in the sediments. Results revealed that the order of antibiotic abundance in sediment was fluoroquinolones > tetracyclines > macrolides > sulfonamides > amphenicols. The total antibiotic concentrations were 0.10-134.4 ng/g (mean: 11.88 ng/g). Of these, fluoroquinolones and tetracyclines were the two dominant antibiotic categories. The dominant occurrence of fluoroquinolones and tetracyclines in sediments suggested that the distribution coefficient (Kd) was one of the important factors to determine their fate. Correlation analysis demonstrated that antibiotic contamination was largely influenced by the local scale of animal husbandry, and the positive correlation between antibiotics and heavy metals was likely driven by their common source of contamination and the complexation. Environmental risk assessment showed that tetracycline and chlortetracycline exhibited potential risks from medium to high in the Yangtze River, although most of the compounds posed minimal and low risks. This work provided a valuable large-scale data set across the whole Yangtze River and revealed the contamination profile of antibiotics. Mitigation and management measures to reduce antibiotic inputs are needed for the Yangtze River basin.


Assuntos
Clortetraciclina , Poluentes Químicos da Água , Animais , Antibacterianos , Ásia , China , Cloranfenicol/análise , Clortetraciclina/análise , Monitoramento Ambiental/métodos , Fluoroquinolonas/análise , Sedimentos Geológicos/análise , Macrolídeos/análise , Medição de Risco , Rios , Sulfonamidas/análise , Tetraciclina , Tetraciclinas/análise , Poluentes Químicos da Água/análise
15.
Occup Ther Int ; 2022: 8199824, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36032183

RESUMO

This paper presents an in-depth study and analysis of the correlation between satisfaction with rural residents' income and mental health well-being in the context of industrial structure upgrading. Most of the studies on residents' subjective well-being from the perspective of relative income or income inequality have started from the happiness of rural residents and the satisfaction of rural residents' life, and few scholars have focused on the psychological health of rural residents. Subjective well-being is significantly related to external and internal goals in desire. Life satisfaction is significantly and positively correlated with external and internal goals, as well as the six dimensions of desire, except for social identity; positive emotions are significantly and positively correlated with internal goals; negative emotions are only negatively correlated with self-acceptance, and there is a significant positive correlation between income level and desire. In vertical income, there is also a process of judging whether the expected income is achieved. If the expected income growth level is achieved, the income satisfaction will increase. Desire mediates the effect of income level on subjective well-being. Income level influences subjective well-being through internal goals; income level influences life satisfaction and positive emotions through external goals. The relationship between income inequality and mental health is influenced by the characteristics of the population, with women and middle-aged people being the most negatively affected. This relationship is also influenced by income level, with the effect of income inequality on mental health showing a negative effect in the lower and middle-income groups but a positive effect in the higher income groups. Income inequality affects residents' mental health through the mediating effects of a sense of social justice, life stress, and trust in government. Inequality in household wealth can exacerbate the negative effects of income inequality on mental health.


Assuntos
Terapia Ocupacional , Satisfação Pessoal , Big Data , China , Feminino , Humanos , Renda , Saúde Mental , Pessoa de Meia-Idade
16.
Front Public Health ; 10: 930842, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36016891

RESUMO

The pandemic-related lifestyle has potentially imposed crucial disturbances on daily and long-term activities, which, in turn, were associated with thought disturbance. This study investigates how the characteristics of the activity system during pandemic-related restrictions are associated with other psychomental aspects. By focusing on PTSD, mentalization, and schizotypal personality, and by inquiring about the main components of the activity system of 852 college students (Zhengzhou, Henan, China)- including the goals orienting their activity, goals' terms and types, the motivation levels and sources, the activity type and engagement time, the flow of the activity, and how due to pandemic lifestyle-results revealed that the activity system's components have significant associations with PTSD, reflective function, and schizotypal traits. Additionally, some of the activity system's elements have a significant predictive role regarding schizotypal traits. The study considered that the life narrative during the pandemic has been disturbed; hence, this may have a crucial effect on mind coherence. Additionally, the outcomes from the pandemic context will support mental health interventions in other similar contexts where the life narrative is severely affected.


Assuntos
COVID-19 , Mentalização , Transtorno da Personalidade Esquizotípica , COVID-19/epidemiologia , Humanos , Personalidade , Transtorno da Personalidade Esquizotípica/psicologia , Estudantes/psicologia
17.
Sci Rep ; 12(1): 11920, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35831383

RESUMO

Spraying occurs by the impact of water droplets on the superhydrophobic wire meshes by liquid penetration during the spreading and recoiling. We have shown that adding a small amount of high molecular weight polymer (PEO) alters the ligaments formation and stabilizes them due to its high elasticity. Consequently, it suppresses droplet spray during droplet spreading and recoiling (recoil penetration). In the wide range of the impact velocities, the penetrated ligaments retracted back to the mesh after reaching the maximum length and eventually merged with the droplet on the mesh. The empirical fitting shows that the ligament evolution follows the parallel spring-dashpot model of Kelvin-Voigt. The additive polymer also changes the recoil penetration mechanisms from cavity collapse to cavity detachment due to the higher retraction velocity of the cavity near the mesh that is induced by the upward flow formed by the retraction of the ligaments to the mother droplet. A model based on mass conservation is proposed to calculate the variation of the maximum ligament size.

18.
J Inflamm Res ; 15: 3447-3466, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35726215

RESUMO

Background: The inflammatory diseases pose a great threat to human health. Variant anti-inflammatory agents have been therefore developed. However, the current anti-inflammatory drugs are still challenged by low response and side effects. There remain great unmet treatments to inflammatory diseases. Methods: In this work, we fabricate a recombinant adeno-associated virus (rAAV), rAAV-DMP-miR533, by packaging a DNA molecule DMP-miR533 into AAV, in which DMP is a NF-κB-activatable promoter composed of a NF-κB decoy and a minimal promoter and miR533 codes an artificial microRNA targeting NF-κB RELA. We evaluate the in vitro and in vivo anti-inflammatory effect of the virus with inflammatory cells and the mice of three typical inflammatory diseases including the dextran sulphate sodium-induced acute colitis, imiquimod-induced psoriasis, and collagen-induced arthritis. Results: We found that rAAV-DMP-miR533 had marked anti-inflammatory effect in both cells and mice. In addition, rAAV-DMP-miR533 showed biosafety in mice. Conclusion: This study thus provides a promising gene therapy to variant inflammatory diseases by directly targeting NF-κB, an established hub regulator of inflammation.

19.
Langmuir ; 38(12): 3860-3867, 2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35293214

RESUMO

When a water droplet strikes a superhydrophobic surface, there may be several to a few tens of rebounds before it comes to rest. Although this intriguing multiphase flow phenomenon has received a great deal of attention from interfacial scientists and engineers, the underlying dynamics have not yet been completely resolved. In this paper, we report on an experimental investigation into the bouncing behavior of water droplets impinging on macroscopically flat superhydrophobic surfaces. We show that the restitution coefficient, which quantifies the energy consumed during impact and rebound, exhibits a nonmonotonic dependence on the Weber number. It is the droplet-surface friction that restricts the rebound height of the impinging droplet, so its restitution coefficient increases with the Weber number when the impact velocity is below a critical value. Above this value, the viscous friction within a thin liquid layer close to the superhydrophobic surface becomes dominant, and thus, the restitution coefficient decreases sharply. On the basis of energy analyses, semiempirical formulas are proposed to describe the restitution coefficient, and these can be employed to predict the number of successive rebounds of impinging droplets on superhydrophobic surfaces.

20.
Phys Chem Chem Phys ; 24(5): 3200-3206, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35043810

RESUMO

Two-dimensional (2D) van der Waals (vdW) heterostructures based on multiferroic materials have potential applications in novel low-dimensional spintronic devices. In this work, we have investigated a strong magnetoelectric coupling and electrical dependence between single layer (1L) Cr2Si2Te6 and In2Se3. By switching the direction of ferroelectric polarization in In2Se3, we observed a significant magneto-crystalline anisotropy energy (MAE) enhancement of Cr2Si2Te6. The analysis of the spin-resolved orbital-decomposed band structure shows stronger magnetoelectric coupling between the In2Se3 and Cr2Si2Te6 layers. The modulation of the electrical features could also be achieved in the switching of the ferroelectric polarization. Furthermore, the switching of Ohmic-Schottky contacts in the heterojunction with different polarization states was successfully achieved under the effect of strain engineering. Based on these findings, we design a novel 2D ferroelectric-ferromagnetic heterojunction that exploits the controllability and nonvolatility of ferroelectrics to modulate the electrical properties of the device. These findings indicate the high application potential of Cr2Si2Te6/In2Se3 multiferroic heterojunctions in spintronics.

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