The way of our living and working has changed intensely throughout the past half-century. The era we live in is interlinked with rapid technological changes, paving the way for digitalization. The ...students are considered digital natives and are expected to have e-learning abilities to improve their academic effectiveness. However, digital readiness is an important factor that can play a valuable role in boosting students’ e-learning abilities and satisfaction. The previous studies of students’ e-learning abilities revealed the lack of students’ digital readiness for academic achievements. Therefore, the present study aims to examine the role of digital readiness in the e-learning satisfaction of students. Based on the theory of motivation, the present study attempts to check the association of digital readiness with e-learning satisfaction. The current study also determines the relationship of digital readiness with entrepreneur psychological capital. Further, this study examines the correlation of entrepreneur psychological capital with e-learning satisfaction. The present study also assumes the mediating role entrepreneur of psychological capital and moderating role of mindfulness. For empirical analyses, this study gathered data from 376 music learning students of entrepreneur training institutes in China through a structured questionnaire method using a convenient sampling technique. This study applied partial least square structural equation modeling for empirical analyses using Smart PLS software. The present study confirmed that digital readiness positively correlates with e-learning satisfaction and psychological capital. The findings also acknowledged that psychological capital positively enhances e-learning satisfaction. The results also confirmed that psychological capital mediates the association between digital readiness and e-learning satisfaction. However, the outcomes revealed that mindfulness does not moderate the association between digital readiness and e-learning satisfaction. On the other hand, the findings acknowledged that mindfulness moderates the relationship between psychological capital and e-learning satisfaction. In addition, this study’s findings also serve the literature by providing important theoretical and practical implications. This study points out that digital readiness is an important antecedent to increasing students’ learning satisfaction and performance. The findings also suggest that students’ mindfulness could play a bridging role in enhancing their performance.
This study has been focused on an experimental investigation of the electrosorption selectivity for alkali- and alkaline-earth cations in activated carbon-based capacitive deionization process. ...Cyclic voltammetry experiments showed that a large proportion of micropores in activated carbon electrodes were associated with electrical double-layer overlapping, and the specific capacitance of cations increased with the decrease of hydrated radius. A series of electrosorption experiments were conducted to identify the preferential electrosorption in multi-ionic solutions. The electrosorption selectivity of cations can be determined by the ionic charge, hydrated radius, and initial molar concentration. The activated carbon electrodes presented greater selectivity of smaller ions over larger ions due to size-affinity, while divalent cations possessing higher valence to screen the surface charge were more effectively removed than monovalent cations. The increase of initial molar concentration resulted in the increase of electrosorption capacity. Moreover, the ion selectivity can be further enhanced by increasing the applied voltage. The results are relevant to water desalination and softening in electrosorption.
► Micropores in activated carbon electrode resulted in electrical double-layer overlapping. ► Electrosorption selectivity was studied in a competitive multi-ionic environment. ► The electrosorption capacity was dependent on the ionic charge and hydrated radius. ► The molar concentration of cations had a critical effect on the sorption capacity. ► Divalent cations were more effectively removed than monovalent cations.
Summary
Microglia‐mediated neuroinflammation plays a dual role in various brain diseases due to distinct microglial phenotypes, including deleterious M1 and neuroprotective M2. There is growing ...evidence that the peroxisome proliferator‐activated receptor γ (PPARγ) agonist rosiglitazone prevents lipopolysaccharide (LPS)‐induced microglial activation. Here, we observed that antagonizing PPARγ promoted LPS‐stimulated changes in polarization from the M1 to the M2 phenotype in primary microglia. PPARγ antagonist T0070907 increased the expression of M2 markers, including CD206, IL‐4, IGF‐1, TGF‐β1, TGF‐β2, TGF‐β3, G‐CSF, and GM‐CSF, and reduced the expression of M1 markers, such as CD86, Cox‐2, iNOS, IL‐1β, IL‐6, TNF‐α, IFN‐γ, and CCL2, thereby inhibiting NFκB–IKKβ activation. Moreover, antagonizing PPARγ promoted microglial autophagy, as indicated by the downregulation of P62 and the upregulation of Beclin1, Atg5, and LC3‐II/LC3‐I, thereby enhancing the formation of autophagosomes and their degradation by lysosomes in microglia. Furthermore, we found that an increase in LKB1–STRAD–MO25 complex formation enhances autophagy. The LKB1 inhibitor radicicol or knocking down LKB1 prevented autophagy improvement and the M1‐to‐M2 phenotype shift by T0070907. Simultaneously, we found that knocking down PPARγ in BV2 microglial cells also activated LKB1–AMPK signaling and inhibited NFκB–IKKβ activation, which are similar to the effects of antagonizing PPARγ. Taken together, our findings demonstrate that antagonizing PPARγ promotes the M1‐to‐M2 phenotypic shift in LPS‐induced microglia, which might be due to improved autophagy via the activation of the LKB1–AMPK signaling pathway.
Bulk photovoltaic effect, a promising optoelectronic phenomenon for generating polarized dependent steady-state photocurrent, has been widely applied in various photodetectors. However, incorporating ...stereochemically active lone pairs to construct bulk photovoltage in organic-inorganic hybrid perovskite (OIHP) is still elusive and challenging. Herein, bulk photovoltage (1.2 V) has been successfully achieved by introducing the stereo-chemically active lone pairs perovskitizer to construct a polar tri-layered hybrid perovskite, namely, (IBA)2MHy2Pb3Br10 (1, IBA= iso-butylamine, MHy = methylhydrazine). Strikingly, owning to the promising bulk photovoltage, 1-based detectors exhibit an ultra-highly sensitive polarized photodetection (polarization ratio of up to 24.6) under self-powered mode. This ratio surpasses all the reported 2D OIHP single-crystal photodetectors. In addition, detectors exhibit outstanding responsivity (~ 200 mA·W-1) and detectivity (~ 2.4 × 1013 Jones). More excitingly, further investigation confirms that lone pair electrons in MHy result in the separation of positive and negative charges to produce directional dipoles, which further directional alignment to generate bulk photovoltage, thereby resulting in polarization-dependent photocurrent. Our findings provide a new demonstration for polar multilayer materials' construction and may open opportunities for a host of high-sensitive polarized photodetection.
Multilayered chiral hybrid perovskites are highly desired for highly‐sensitive circularly polarized light (CPL) detection rooted in their efficient charge transport and strong chiroptical activity. ...However, designing multilayered chiral hybrid perovskites remains a huge challenge. Here, through pairing achiral ethylamine (EA)−chiral arylamine in the interlayer space, multilayered chiral alternating cations intercalation‐type (ACI) hybrid perovskites (R‐/S‐PPA) EA2Pb2Br7 (PPA = 1‐phenylpropylamine) are successfully obtained. Significantly, perovskitizer EA extends the thickness of the quantum well and alternating space cation EA greatly alleviates in‐plane tilting distortions of adjacent metal halide octahedra, providing fast channels for in‐plane carrier transport. Consequently, single‐crystal photodetectors of (R‐/S‐PPA) EA2Pb2Br7 exhibit high circular polarization sensitivity with a large anisotropy factor of 0.3, which falls around the highest value among the layered hybrid perovskites. In addition, a fast responding rate (τr )of 308 µs and a high CPL‐detectivity of 8 × 1012 Jones are also presented. This work opens up a new perspective to design multilayered chiral hybrid perovskites for high‐sensitive CPL detection.
High‐sensitive circularly polarized light detection was realized in multilayered hybrid perovskite enantiomers which are designed by paring ethylamine and chiral arylamine cations in the interlayered space.
For the PDPP3T/PCBM system investigated here, atomic force microscopy, resonant soft X‐ray scattering, and grazing incidence wide angle X‐ray scattering are used as an initial set of tools to ...determine the surface texture, the bulk compositional morphology, and the crystallization behavior, respectively. We find systematic variations and relate them to device performance. A solvent mixture of DCB/CF/DIO = 76:19:5 (v/v/v) yields a PCE of 6.71%.
Ferroelectric materials, particularly the emerging layered hybrid ferroelectrics, have shown great potential for high‐sensitive polarization photodetection owing to their striking bulk photovoltaic ...effect (BPVE). Despite recent great achievements, the linear photoresponse range based on single‐mode BPVE is still limited in the shortwave region due to the large intrinsic bandgaps. Herein, first, the realization of self‐powered visible–infrared polarization photodetection by exploiting dual‐modal BPVE in a newly developed layered Dion–Jacobson (D‐J) hybrid ferroelectric (BDA)(EA)2Pb3Br10 (1, BDA is 1,4‐butadiammonium, EA is ethylammonium) is reported. Crystallographic investigations indicate that 1 adopts a typical trilayered D‐J perovskite structure with a fascinating ferroelectric feature and a giant two‐photon absorption coefficient as giant as 4.73 cm MW–1. Meanwhile, the bulk single crystal device of 1 exhibits excellent self‐powered direct detection performance under both visible light (405 nm) and near‐infrared light (800 nm), with a current on/off ratio as high as 103. More intriguingly, the device displays high sensitivity to the polarization of illuminated light, showing a considerable anisotropy up to 4.2 (405 nm) and 4.8 (800 nm), which are much larger than the detectors achieved by geometry anisotropy. The realization of self‐powered visible‐infrared dual‐modal polarization photodetection in 1 indicates the tremendous potential of hybrid ferroelectrics in various optoelectronic applications.
In this manuscript, by exploiting dual‐modal ferroelectric photovoltaic effect in a Dion–Jacobson hybrid perovskite (BDA)(EA)2Pb3Br10 (1, BDA is 1,4‐butadiammonium, EA is ethylammonium), high‐performance self‐powered polarization photodetection is realized in the visible and infrared region with a polarization ratio up to 4.2 (visible region) and 4.8 near infrared region. This work prophesies the tremendous potential of hybrid ferroelectrics in various optoelectronic applications.
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•The initial and complete cleaning thresholds of 2 μm oxide layer were 12.7 J/cm2 and 25.5 J/cm2, respectively.•Thermal stress coupling effect led to the separation of substrate and ...oxide layer.•Phase explosion and impact effect led to the splattering and removal of oxide.•Energy density affects plasma characteristic by changing plasma temperature and electron density.
Through comparing the cleaning effect of aluminum alloy at different energy densities, the model of materials thermodynamics was established, illuminating the cleaning mechanism and plasma behavior. The research showed laser cleaning could remove oxide layer completely. The initial cleaning threshold was 12.7 J/cm2 and complete cleaning threshold was 25.5 J/cm2. At low energy density, phase explosion caused by laser ablation was the main cleaning mechanism. At high energy density, besides phase explosion, impact effect induced by evaporation pressure caused the splattering and removal of oxide layer. Plasma lifespan had positive correlation with energy density. Its lifespan in 25.5 J/cm2 and 51.0 J/cm2 were about 6 μs and above 10 μs, respectively. The model of materials thermodynamics showed that at low energy density, substrate evaporation pushed out molten oxide layer and formed pulse craters. At high energy density, transient energy absorption caused thermal stress coupling effect and separated substrate with oxide layer. The impact effect induced by evaporation pressure resulted in the removal of oxide layer. The vapor of Al absorbed laser energy and formed plasma. The high energy density enhanced the laser-plasma coupling. It caused high temperature and intensive electron density. The time of plasma cooling and atomization became longer.
Quasi‐two‐dimensional (Q‐2D) Dion‐Jacobson (DJ) organic‐inorganic hybrid perovskites based on CsPbBr3 are promising candidates for photodetection. Previous studies have predicted that the ...photoresponse of such materials with high inorganic‐layer numbers (n) will be more protruding in this portfolio. However, until now, only bilayered (n=2) CsPbBr3‐based DJ‐type hybrid perovskites are obtained and the higher number of layers (n>2) remain completely unexplored, owing to the relatively high formation energies. Here, by incorporating diamine into the 3D CsPbBr3 motif, a new Q‐2D trilayered CsPbBr3‐based DJ‐type hybrid perovskite that contains organic cation and inorganic Cs metal, namely (4‐AMP)Cs2Pb3Br10 (1, 4‐AMP2+=4‐(aminomethyl)piperidinium, n=3), is obtained. Excitingly, 1 exhibits excellent photoresponse, superior to its single‐layered and bilayered counterparts. The resulting photodetectors thus exhibit a large on/off ratio (>103), high photodetectivity (6.5×1010 Jones) and fast response speed (193 μs). As far as we know, 1 is the first Q‐2D CsPbBr3‐based DJ‐type hybrid perovskites with high n numbers. Our results may widen the range of the potential material in application of photodetection and will be helpful to design hybrid perovskites for other advanced optoelectronic devices.
Photodetectors: By incorporating diamine into the 3D CsPbBr3 motif, the first quasi‐2D trilayered CsPbBr3‐based Dion‐Jacobson hybrid perovskite (4‐AMP)Cs2Pb3Br10 (1, where 4‐AMP2+=4‐(aminomethyl)piperidinium), is acquired. Photodetectors based on 1 exhibit excellent photoresponse, superior to its monolayered and bilayered counterparts. Our results may widen the range of the potential material of photodetection and will be helpful to design hybrid perovskites for other advanced optoelectronic devices.
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