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Counterintuitive temperature dependence of isospin flavor polarization has recently been found in twisted bilayer graphene, where unpolarized electrons in a Fermi liquid become a spin–valley polarized insulator upon heating. So far, the effect has been limited to v = +/−1 (one electron/hole per superlattice cell), leaving open questions such as whether it is a general property of symmetry-breaking electronic phases. Here, by studying a rhombohedral trilayer graphene/boron nitride moiré superlattice, we report that at v = −3 a resistive peak emerges at elevated temperatures or in parallel magnetic fields. Concomitantly, the Hall carrier density tends to reset at the integer filling, signaling spin–valley flavor symmetry breaking. These phenomena can also be observed at v = −1 and −2 when the displacement field is large enough to suppress correlated insulators at low temperatures. Our results greatly expand the scope for observing the counterintuitive temperature dependence of flavor polarization, i.e., the regimes proximal to symmetry-breaking phases where the flavor polarization order strongly fluctuates, encouraging more experimental and theoretical exploration of isospin flavor polarization dynamics in flat-band moiré systems. In moiré superlattices of rhombohedral trilayer graphene aligned on boron nitride, heating may counterintuitively promote spin–valley polarization, transforming metallic ground states into insulators at high temperatures, which deepens the understanding of isospin flavor polarization in correlated electronic systems. [ABSTRACT FROM AUTHOR]

Background: Platelet is enriched with Circular RNAs (circRNAs), with circFAM13B rank among the 10 most abundant circRNAs in platelets. The aim of the present study was to evaluate the predictive value of platelet-derived circFAM13B for the antiplatelet responsiveness and efficacy of ticagrelor in patients with acute coronary syndrome (ACS). Methods: Consecutive ACS patients treated with ticagrelor were enrolled, and the antiplatelet responsiveness of 3 days of ticagrelor maintenance treatment was assessed by measuring the adenosine diphosphate (ADP)-induced platelet inhibition rate (ADP%) using thromboelastography. The expression of circFAM13B in the patients' platelets was analyzed by quantitative real-time polymerase chain reaction. The correlation between circFAM13B expression and ticagrelor antiplatelet responsiveness, as well as the independent contribution of circFAM13B to the composite of adverse ischemic events during a follow-up period of at least 12 months was evaluated. Results: A total of 129 eligible ACS patients treated with ticagrelor were enrolled in the study. A negative correlation was found between the expression of circFAM13B and the ADP% value (r = -0.41, P < 0.001). Patients with ADP% ≥ 76% had a significantly lower level of circFAM13B compared to those with ADP% < 76% (adjusted P = 0.009). Receiver operating characteristic curve analysis demonstrated that combining circFAM13B expression > 1.05 with clinical risk factors could effectively predict the risk of adverse ischemic events (AUC = 0.81, 95% CI: 0.69 to 0.92, P < 0.001). Kaplan-Meier survival analysis showed that patients with circFAM13B > 1.05 had a significantly higher risk of adverse ischemic events compared to those with circFAM13B ≤ 1.05 (P = 0.003). Multivariate logistic hazard analysis identified circFAM13B > 1.05 as an independent risk factor for adverse ischemic events in in ticagrelor-treated ACS patients (adjusted OR: 5.60, 95% CI: 1.69–18.50; P = 0.005). Conclusions: Platelet-derived circFAM13B could be utilized for predicting the antiplatelet responsiveness and efficacy of ticagrelor in patients with ACS. [ABSTRACT FROM AUTHOR]

Band alignment engineering in 2D van der Waals heterostructures is a promising method for manufacturing high‐speed, high‐responsivity, and high‐gain photodetectors. Here, a heterojunction photodetector with the band alignment transition from type I to type II under the bias voltage using narrow bandgap material n‐Bi2Se3 and polarization‐sensitive material p‐GeSe is designed and prepared. This photodetector possesses excellent performance of broadband detection (532‐1550 nm), high responsivity (5.86 × 103 A W−1), high detectivity (1.50 × 1013 Jones), significant external quantum efficiency (1.15 × 106%) and fast response time (97 µs). Compared with the conventional type II band alignment, an additional triangular potential barrier is generated in this type II band alignment evolved from type I. Notably, this triangular barrier will block photogenerated carriers in Bi2Se3, which leads to high external quantum efficiency; Furthermore, photogenerated holes can tunnel through this barrier, effectively shortening the response time. Meanwhile, the device can achieve polarization detection (anisotropic ratio = 1.74 at 808 nm) and polarization imaging, which is of great significance for reducing the bit error rate in complex environments. [ABSTRACT FROM AUTHOR]

Broadband photodetectors based on narrow bandgap 2D materials have garnered considerable interest for application in the field of optoelectronic devices. However, their large dark current hinders device performance. In this work, a PtSe2/MoS2 heterojunction was fabricated for a broadband photodetector operating within the range of visible to near-infrared. The device exhibited suppressed dark currents with a high rectification ratio of 104. The built-in electric field of the heterojunction promoted carrier separation effectively, and the device achieved excellent photoelectric performance with responsivities of 1.7 × 103, 27.52, and 21 mA/W at 635, 785, and 1550 nm wavelengths, respectively. Moreover, the specific detectivities (D*) were 2.2 × 1013 Jones (635 nm), 3.55 × 1011 Jones (785 nm), and 2.72 × 108 Jones (1550 nm). The device demonstrated a rise/fall time of 131/241 µs under 1550 nm laser illumination. Visible and near-infrared imaging detection was also demonstrated based on the heterojunction device at room temperature. This work sheds light on the remarkable potential of PtSe2/MoS2 heterojunctions in the domain of high-performance broadband photodetectors. [ABSTRACT FROM AUTHOR]

This research utilized Jintang navel oranges as the primary raw material, and employed two distinct yeast strains, Saccharomyces cerevisiae SC-125 and Angel yeast SY, for a dual fermentation approach. Employing single-strain fermentation as the control, this study aims to ascertain the physicochemical markers, alterations in organic acids and amino acids, alongside the antioxidant properties throughout the fermentation process, all within an optimized environment. The characterization of flavor compounds in the navel orange wines subjected to diverse yeast strains and mixed fermentation was conducted using headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HP-SPME/GC-MS). This method facilitated the identification of flavor compound types and concentrations. Moreover, electronic sensory systems including electronic noses and electronic eyes were harnessed to discern distinctions among various navel orange wines. Through these techniques, the research aimed to elucidate the variances induced by different yeast strains during both individual and mixed fermentation processes, shedding light on their impacts on the ultimate quality of navel orange wines. [ABSTRACT FROM AUTHOR]

The fuel cell with a ten-channel serpentine flow field has a low operating pressure drop, which is conducive to extended test operations and stable use. According to numerical results of the ten-channel serpentine flow field fuel cell, the multi-channel flow field usually has poor mass transmission under the ribs, and the lower pressure drop is not favorable for drainage from the outlet. In this paper, an optimized flow field is developed to address these two disadvantages of the ten-channel fuel cell. As per numerical simulation, the optimized flow field improves the gas distribution in the reaction area, increases the gas flow between the adjacent ribs, improves the performance of PEMFC, and enhances the drainage effect. The optimized flow field can enhance water pipe performance, increase fuel cell durability, and decelerate aging rates. According to further experimental tests, the performance of the optimized flow field fuel cell was better than that of the ten-channel serpentine flow field at high current density, and the reflux design requires sufficient gas flow to ensure the full play of the superior performance. [ABSTRACT FROM AUTHOR]

Correlating atomic configurations—specifically, degree of disorder (DOD)—of an amorphous solid with properties is a long-standing riddle in materials science and condensed matter physics, owing to difficulties in determining precise atomic positions in 3D structures1–5. To this end, 2D systems provide insight to the puzzle by allowing straightforward imaging of all atoms6,7. Direct imaging of amorphous monolayer carbon (AMC) grown by laser-assisted depositions has resolved atomic configurations, supporting the modern crystallite view of vitreous solids over random network theory8. Nevertheless, a causal link between atomic-scale structures and macroscopic properties remains elusive. Here we report facile tuning of DOD and electrical conductivity in AMC films by varying growth temperatures. Specifically, the pyrolysis threshold temperature is the key to growing variable-range-hopping conductive AMC with medium-range order (MRO), whereas increasing the temperature by 25 °C results in AMC losing MRO and becoming electrically insulating, with an increase in sheet resistance of 109 times. Beyond visualizing highly distorted nanocrystallites embedded in a continuous random network, atomic-resolution electron microscopy shows the absence/presence of MRO and temperature-dependent densities of nanocrystallites, two order parameters proposed to fully describe DOD. Numerical calculations establish the conductivity diagram as a function of these two parameters, directly linking microstructures to electrical properties. Our work represents an important step towards understanding the structure–property relationship of amorphous materials at the fundamental level and paves the way to electronic devices using 2D amorphous materials.Varying growth temperatures enables the tuning of the degree of disorder, which is fully described by the absence/presence of medium-range order and temperature-dependent densities of nanocrystallites, and electrical conductivity in amorphous monolayer carbon films. [ABSTRACT FROM AUTHOR]

The comorbid mechanism of depression and chronic pain has been a research hotspot in recent years. Until now, the role of purinergic signals in the comorbid mechanism of depression and chronic pain has not been fully understood. This review mainly summarizes the research results published in PubMed during the past 5 years and concludes that purinergic signaling is a potential therapeutic target for comorbid depression and chronic pain, and the purinergic receptors A1, A2A, P2X3, P2X4, and P2X7and P2Y6, P2Y1, and P2Y12 may be important factors. The main potential pathways are as follows: A1 receptor-related G protein-dependent activation of introverted K+ channels (GIRKs), A2A receptor-related effects on the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) and MAPK/nuclear factor-κB (NF-κB) pathways, P2X3 receptor-related effects on dorsal root ganglia (DRG) excitability, P2X4 receptor-related effects on proinflammatory cytokines and inflammasome activation, P2X7 receptor-related effects on ion channels, the NLRP3 inflammasome and brain-derived neurotrophic factor (BDNF), and P2Y receptor-related effects on the phospholipase C (PLC)/inositol triphosphate (IP3)/Ca2+ signaling pathway. We hope that the conclusions of this review will provide key ideas for future research on the role of purinergic signaling in the comorbid mechanism of depression and chronic pain. [ABSTRACT FROM AUTHOR]

Two-dimensional electron gas systems (2DEGs) generated at the oxide interfaces that exhibit rich physics phenomena opened up an era for oxide-based electronics, photonics, and spintronics. The recent discovery of superconductivity plus the strong spin-orbital coupling naturally existing in the 2DEGs of KTaO3 (KTO) made KTO an exciting platform for the interplay of the electronic and spin degrees of freedom to create exotic physical properties. By directly placing KTO's 2DEGs next to another strongly-correlated oxide with nontrivial topological nodes, we reveal the anomalous effects which were induced by the topological states in the electronic transport properties of the KTO's 2DGEs, due to the electronic reconstruction caused by the proximity effect. This adds an additional prospect to the functions of KTO heterostructures. [ABSTRACT FROM AUTHOR]

The ABCD-GENE score was constructed to identify patients with high platelet reactivity (HPR) after 30 days of clopidogrel treatment. In our study, 1297 eligible patients with acute coronary syndrome (ACS) were included, and 44 (3.4%) major adverse cardiovascular events (MACEs) occurred during the 12-month clopidogrel treatment. The score with a cutoff of ≥ 10 was independently associated with the risk of 5-day HPR (adjusted HR: 1.73, 95% CI: 1.09–2.74, P = 0.020) and MACEs (adjusted HR: 2.25, 95% CI: 1.19–4.25, P = 0.013). The risk of MACEs increased when the multivariable model with the score (≥ 10) plus 5-day HPR was used (adjusted HR: 4.37, 95% CI: 1.90–10.10, P = 0.001). The c-statistic for MACEs was 0.60 when using the score threshold of ≥ 10 and 0.63 when using the model with the score plus 5-day HPR. As a simple tool, the ABCD-GENE score could identify clopidogrel-treated Chinese patients with ACS who are at increased risk of MACEs. The addition of 5-day HPR could slightly improve the diagnostic ability of the score. [ABSTRACT FROM AUTHOR]

The characterization and bioactive properties of carotenoid produced by Gordonia rubripertincta GH-1 originating from Pixian Douban (PXDB), the Chinese traditional condiment, was investigated. The produced and purified yellow pigment was characterized by ultraviolet-visible spectroscopy (UV-Vis), Fourier transformed infrared (FTIR), nuclear magnetic resonance (NMR), and high-resolution mass spectrometry (HRMS), and was identified as carotenoid lutein. Additionally, the bioactive activity of lutein from G. rubripertincta GH-1 was evaluated by measuring the free radical scavenging capacity in vitro and feeding zebrafish lutein through aqueous solution. The results showed that the carotenoid lutein had strong antioxidant capacity and a protective effect on zebrafish eye cells, which could inhibit the apoptosis of eye cells in a concentration dependent manner. The results suggested that carotenoid lutein from G. rubripertincta GH-1 could be utilized as a potential source of natural antioxidants or functional additives for food/pharmaceutical industries. [ABSTRACT FROM AUTHOR]

Background: This study aimed to evaluate the efficacy and safety of oral anticoagulants (OACs) in real-world elderly patients with comorbidities of stable coronary artery disease (SCAD) and atrial fibrillation (AF). Methods: Elderly patients (aged ≥ 65 years old) diagnosed with SCAD and AF were consecutively recruited and grouped into patients with or without oral anticoagulant (OAC) treatment. Follow-up was performed for 5 years. Major adverse cardiac events (MACEs) were defined as a composite of all-cause death, nonfatal myocardial infarction (MI), nonfatal stroke, and systemic embolism. Major bleeding outcomes were defined as events that were type ≥ 3 based on the Bleeding Academic Research Consortium (BARC) criteria. The net clinical outcomes were defined as the combination of MACEs and bleeding of BARC type ≥ 3. Results: A cohort of 832 eligible patients (78 ± 6.70 years) was included. Compared to the patients without OAC treatment (n = 531, 63.82%), the patients treated with OAC (n = 301, 36.18%) were much younger, had higher body mass index (BMI), and had lower prevalence of heart failure, chronic obstructive pulmonary disease (COPD), renal insufficiency, and previous myocardial infarction. During the follow-up of 5 years, compared to the patients without OAC treatment, patients with OAC had a significantly lower risk of MACEs (20.60% vs. 58.95%, adjusted HR: 0.21, 95% CI: 0.15–0.30, p < 0.001) but a higher risk of BARC ≥ 3 bleeding events (4.65% vs. 1.32%, adjusted HR: 4.71, 95% CI: 1.75–12.64, p = 0.002). In combination, a lower risk of net clinical outcomes could be observed in the patients with OACs (23.26% vs. 58.96%, adjusted HR: 0.27, 95% CI: 0.19–0.38, p < 0.001). Among the patients with OAC treatment, no significant difference was found for MACEs or BARC ≥ 3 bleeding events between the patients with or without comedications of oral antiplatelet agents. Conclusions: A net clinical benefit of efficacy and safety could be observed in OAC-treated elderly patients with SCAD and AF. This benefit is independent of the comedications of oral antiplatelet treatment. [ABSTRACT FROM AUTHOR]

Background: Despite strong antiplatelet therapy with ticagrelor, serious ischemic events still occur in patients with acute coronary syndrome (ACS). The predictability of platelet reactivity to the residual risk of ischemic events during ticagrelor treatment remains uncertain. Objectives: We aimed to investigate the predictability of the thromboelastography (TEG)-measured adenosine disphosphate (ADP)-induced platelet inhibition rate (ADP%) to the ischemic events in ticagrelor-treated patients with ACS. Methods: A cohort of ticagrelor-treated patients with ACS were consecutively recruited. ADP% was measured by TEG after 3 days of ticagrelor maintenance treatment. The primary ischemic event was defined as rehospitalization for unstable angina (UA) within 1 year, and the secondary ischemic event was a composite of the primary ischemic event plus all-cause death, nonfatal myocardial infarction (MI), stent thrombosis, stroke, and unplanned revascularization within 1 year. Results: A total of 751 eligible patients with ACS were included in the analysis, with 336 patients randomly assigned to the derivation group and 415 to the validation group. The overall rates of primary and secondary ischemic events were 14.51% (n = 109) and 16.91% (n = 127), respectively. Compared to the patients without ischemic events, those with ischemic events had a significantly lower ADP% both in the derivation group (for primary ischemic events: 66.05% vs. 92.80%, p < 0.001; for secondary ischemic events: 66.05% vs. 93.20%, p < 0.001) and in the validation group (for primary ischemic events: 66.40% vs. 89.20%, p < 0.001; for secondary ischemic events: 66.90% vs. 89.20%, p < 0.001). Receiver operating characteristic curve (ROC) analysis showed that an ADP% < 76% was the optimal cut-off value for predicting 1-year primary ischemic events, with an area under the curve (AUC) of 0.80 (95% CI: 0.72–0.86, p < 0.001) in the derivation group and 0.77 (95% CI: 0.69–0.85, p < 0.001) in the validation group. The multivariate Cox regression hazard analysis consistently identified an ADP% < 76% as an independent predictor of primary ischemic events in the derivation group (HR: 8.21, 95% CI: 4.82–13.99, p < 0.001) and in the validation group (HR: 6.34 95% CI: 3.32–12.11, p < 0.001). There was also a strong association between an ADP% < 76 and the occurrence of secondary ischemic events in the derivation group (HR: 7.33, 95% CI: 4.47–12.00, p < 0.001) and in the validation group (HR: 4.76, 95% CI: 2.73–8.32, p < 0.001). Conclusion: The ADP-induced platelet inhibition rate measured by TEG could predict ischemic events in ticagrelor-treated patients with ACS. [ABSTRACT FROM AUTHOR]

Halide perovskites are widely explored as efficient photoresponsive materials for optoelectronic devices. However, understanding and controlling their underlying optical and electrical properties remains limited. Here, a novel approach is developed by introducing silver sulfide (Ag2S) quantum dots (QDs) into an MAPbBr3 single crystal. The high‐quality Ag2S‐quantum‐dot‐in‐perovskite (Ag2S‐QDiP) matrixes synthesized through a laser‐assisted inverse temperature crystallization (LA‐ITC) strategy show broadband light‐sensitive wavelength from 550 to over 1000 nm, and a balanced carriers mobility facilitates their transmission and collection. A Ag2S‐QDiP‐enabled photodetector is demonstrated, which exhibits considerably enhanced responsivity and detectivity of 1.17 A W−1 and 6.24 × 1014 Jones at 532 nm, and 57.69 mA W−1 and 1.03 × 1011 Jones at 1064 nm, respectively. The enhanced performance in the near‐infrared (NIR) region can be attributed to the discrete heterojunction formed between MAPbBr3 and Ag2S QDs, which enhances the light absorption in the NIR range and facilitates photogenerated excitons' separation at the interface. The facile synthesis process, the more balanced transport behavior, and the ensuing improved device performance highlight introducing QDs into perovskite single crystal as an efficient strategy for tuning fundamental properties of perovskite and for developing high‐efficiency broadband electronic and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Background. This study aimed to analyse the role of the HAS-BLED score with the addition of genotype bins for bleeding risk prediction in warfarin-treated patients with atrial fibrillation (AF). Methods and Results. Consecutive patients with AF on initial warfarin treatment were recruited. For each patient, CYP2C9 ∗ 3 and VKORC1-1639 A/G genotyping was performed to create 3 genotype functional bins. The predictive values of the HAS-BLED score with or without the addition of genotype bins were compared. According to the carrier status of the genotype bins, the numbers of normal, sensitive, and highly sensitive responders among 526 patients were 64 (12.17%), 422 (80.23%), and 40 (7.60%), respectively. A highly sensitive response was independently associated with clinically relevant bleeding (HR: 3.85, 95% CI: 1.88–7.91, P = 0.001) and major bleeding (HR:3.75, 95% CI: 1.17–11.97, P = 0.03). With the addition of genotype bins, the performance of the HAS-BLED score for bleeding risk prediction was significantly improved (c-statistic from 0.60 to 0.64 for clinically relevant bleeding and from 0.64 to 0.70 for major bleeding, P < 0.01). Using the integrated discriminatory, net reclassification improvement, and decision curve analysis, the HAS-BLED score plus genotype bins could perform better in predicting any clinically relevant bleeding than the HAS-BLED score alone. Conclusions. Genotypes have an incremental predictive value when combined with the HAS-BLED score for the prediction of clinically relevant bleeding in warfarin-treated patients with AF. [ABSTRACT FROM AUTHOR]

Neuropathic pain is a complex disease with high incidence. Adenosine triphosphate (ATP) and its activated P2X7 receptor are involved in the signal transmission of neuropathic pain. Gallic acid (3,4,5-trihydroxybenzoic acid) is a traditional Chinese medicine obtained from natural plants that exhibit anti-inflammatory, analgesic, and antitumor effects. However, the underlying mechanism for gallic acid in analgesia remains unknown. This study aims to reveal how gallic acid alleviates neuropathic pain behaviors in a rat model with chronic constriction injury (CCI). Real-time PCR, western blotting, double-label immunofluorescence, molecular docking, and whole-cell patch clamp technology were used to explore the therapeutic action of gallic acid on neuropathic pain. The results showed that after CCI rats were treated with gallic acid for 1 week, the mechanical withdrawal threshold and thermal withdrawal latency were increased, accompanied by inhibition of the upregulated expression of P2X7 and TNF-α at both mRNA and protein levels, and reduced NF-κB and phosphorylated-STAT3 in the dorsal root ganglia. At the same time, gallic acid significantly decreased the coexpression of P2X7 and glial fibrillary acidic protein in the dorsal root ganglia. In addition, gallic acid could suppress ATP-activated current in human embryonic kidney 293 (HEK293) cells transfected with the plasmid expressing P2X7 but had no effect on ATP activation current of P2X7-mutant plasmid (with the point mutation sequence of the key site where gallic acid binds to the P2X7 receptor). Therefore, our work suggests that gallic acid may alleviate neuropathic pain in CCI rats by inhibiting the P2X7 receptor and subsequent activation of the TNF-α/STAT3 signaling pathway. [ABSTRACT FROM AUTHOR]

Summary: This article proposes an idea of using the multi‐inlet divergent inlet in proton exchange membrane fuel cell (PEMFC) to replenish the reaction gas for the main flow channel. New cathode flow field models such as the divergent flow field and the confluent flow field are developed and analyzed to mitigate some bad influences caused by the linear consumption of the reaction gas. The single layer PEMFC models are developed and simulated by using the ANSYS FLUENT software. Then, the performances and flow characteristics of PEMFC models are compared, and different inlet flow ratios are optimized in the multi‐inlet design scheme. Finally, the results show good improvements of the performance and water removal effect while reducing the pressure drop. [ABSTRACT FROM AUTHOR]

Grains and grain boundaries play key roles in determining halide perovskite‐based optoelectronic device performance. Halide perovskite monocrystalline solids with large grains, smaller grain boundaries, and uniform surface morphology improve charge transfer and collection, suppress recombination loss, and thus are highly favorable for developing efficient solar cells. To date, strategies of synthesizing high‐quality thin monocrystals (TMCs) for solar cell applications are still limited. Here, by combining the antisolvent vapor‐assisted crystallization and space‐confinement strategies, high‐quality millimeter sized TMCs of methylammonium lead iodide (MAPbI3) perovskites with controlled thickness from tens of nanometers to several micrometers have been fabricated. The solar cells based on these MAPbI3 TMCs show power conversion efficiency (PCE) of 20.1% which is significantly improved compared to their polycrystalline counterparts (PCE) of 17.3%. The MAPbI3 TMCs show large grain size, uniform surface morphology, high hole mobility (up to 142 cm2 V−1 s−1), as well as low trap (defect) densities. These properties suggest that TMCs can effectively suppress the radiative and nonradiative recombination loss, thus provide a promising way for maximizing the efficiency of perovskite solar cells. [ABSTRACT FROM AUTHOR]

Nonradiative recombination loss is a key process that determines the performance of perovskite solar cells, and how to control it is significant for the research and development of perovskites. Generally, traditional chemical modification/passivation methods are complicated and prone to secondary contamination. Herein, femtosecond (fs) laser polishing as a promising technique is demonstrated to ameliorate the surface of perovskite films, reduce nonradiative recombination loss, and improve solar cell performance. The high‐intensity fs laser pulses can remove around 20 nm‐thick perovskite top layer through an ionization process, help to decrease the grain boundary density, and enlarge the grain size of perovskite films after recrystallization. It is believed that fs laser polishing is a time‐effective and highly precise technique that is suitable for large‐scale device production, thus will trigger more applications in optoelectronics. [ABSTRACT FROM AUTHOR]

In this paper, we proposed a novel approach for rapid and flexible fabrication of self-driven microfluidic surface enhanced Raman scattering (SERS) chips for quantitative analysis of Hg2+ by femtosecond laser direct writing. In contrast to traditional microfluidic chips, the microchannels of the device can drive a liquid sample flow without external driving force. The sample flow speed is tunable since the wettability and capillarity properties of the channels, which depend on the roughness and the inner diameter of the microchannels, can be controlled by optimizing the laser processing parameters. The SERS active detection sites, which exhibit high enhancement effects and fine reproducibility, were integrated through the femtosecond laser-induced periodic surface structures (LIPSS), followed by 30 nm Ag deposition. The SERS performance of the as-prepared microfluidic SERS detection chip was studied with R6G as probe molecules. The quantitative analysis of Hg2+ was realized by simply injecting the Hg2+ sample and the probe molecules R6G from the two inlets, separately, and collecting the SERS signal at the detection site. The lowest detection limit for Hg2+ is 10−9 M. It should be mentioned that this study is not only limited to Hg2+ quantitative analysis, but is also mainly aimed to develop a new technique for the design and fabrication of novel self-driven microfluidic devices depending on practical application requirements. [ABSTRACT FROM AUTHOR]

Luminescent and hydrophobic textile coatings with recyclability and self-healing capability against both chemical and physical damage were prepared, which present multi-functions and long service life cycles. The applications in self-cleaning, oil-water separation, and anti-counterfeit technology were successfully demonstrated. The coatings can be easily created onto different fabrics including cotton cloth, filter paper, and chemical fabric. A rare earth organic complex of SmTTAPhen(NO3)3 (STPN), silane modified epoxy oligomer, and bis(4-maleimidophenyl)methane (BMI) provide luminescence, hydrophobicity, as well as recyclability and self-healing capability, respectively, to the coatings. More specifically, high transparency but high luminescence were achieved due to the good dispersion of STPN in coating matrix, resulting from the hydron bonding between nitrate groups from STPN and hydroxyl groups from epoxy oligomer. Silane modification facilitated the accumulation of Si–O bonds on the free-surface of the coating, which offers hydrophobic features. The introduction of reversible Diels-Alder reactions provided the self-healing capability and recyclability. Upon heating using an electronic iron, the hydrophobicity can be recovered from physical or chemical damage to the coatings. Besides, the coatings on abandoned fabrics can be recycled and reused to a new bare fabric. We believe that the concept and coating materials are useful to further expand the areas of smart and multi-functional coatings with long service life. [ABSTRACT FROM AUTHOR]

For solid oxide fuel cell (SOFC) stacks, it is generally agreed that the distribution qualities of the fuel and air flows would determine the temperature and pressure distribution within the stack. The flow distribution within the stack is considered to depend largely on the geometry of the stack. According to the direction of inlet flow and outlet flow, the designs of the stack can be divided into U-type structure and Z-type structure, and stacks with two structural characteristics should have some similar flow characteristics. Researchers generally have different degrees of understanding of Z- or U-type characteristics, but there are few intuitive experiments and reports on these two types of structures at a larger stack scale. In this paper, two typical one-in-one output stacks with 30 layers in Z-type and U-type models are developed to investigate the general flow distribution. [ABSTRACT FROM AUTHOR]

Epoxy coatings which can be healed via photothermal effect from focused sunlight are reported. The diamine of m-xylylenediamine (MXDA) and monoamine of 4-(heptadecafluorooctyl)aniline (HFOA) are reacted into the diglycidylether of bisphenol A (DGEBA) network. Via gradual replacement of MXDA with HFOA, the glass transition temperature and crosslinking density of the epoxy network are tuned to achieve the thermally induced healing based on chain diffusion and reentanglement. Aniline black (AB) with well absorptivity for sunlight is used subsequently as the organic photothermal compound, transferring the thermally induced healing into a sunlight responsive one. A common handheld magnifier, which can focus natural sunlight to the required power density (0.6-0.9 W cm−1), is used to successfully heal one cracked coating in outdoor circumstance. This study provides a potential approach to achieve the convenient, precise, and timely healing for outdoor epoxy coatings. [ABSTRACT FROM AUTHOR]

The development of efficient electrocatalyst to produce molecular hydrogen from water is receiving considerable attention, in an effort to decrease our reliance on fossil fuels. The prevention of the aggregation of active sites during material synthesis, in order to increase charge transport properties of electrocatalysts, is needed. We have designed, synthesized, and studied a Ag2S/reduced graphene oxide (rGO) electrochemical catalyst (for hydrogen evolution) from water. The Ag2S nanocrystals were synthesized by the solvothermal method in which the rGO was added. The addition of the rGO resulted in the formation of smaller Ag2S nanocrystals, which consequently increased the electrical conductivity of the composite catalyst. The composite catalyst showed a higher electrochemical catalytic activity than the one with an absence of rGO. At a current density of 10 mA/cm2, a low overpotential of 120 mV was obtained. A Tafel slope of 49.1 mV/dec suggests a Volmer–Herovsky mechanism for the composite catalyst. These results may provide a novel strategy for developing hydrogen evolution reaction (HER) electrocatalysts, via the combining of a nano-semiconductor catalyst with a 2D material. [ABSTRACT FROM AUTHOR]

Despite its extensive research in photovoltaics and light emitting diodes, the charge transport properties of all‐inorganic perovskite cesium lead bromide (CsPbBr3) remain elusive. Clarification of the intrinsic charge transport of this perovskite material is highly desirable, which will help to understand its working mechanism and fabricate high performance electronic devices. Here, it is demonstrated that the phototransistors based on CsPbBr3 microplates show anomalous ambipolar transport characteristics at room temperature. The hole mobility shows light dependence, while the electron mobility is identical under various light incidence. The hole mobility increases from 0.02 cm2 V−1 s−1 (in dark conditions) to 0.34 cm2 V−1 s−1 (50 mW cm−2); while the threshold voltage is shifted by 14 V when electron is the majority charge carrier. The anomalous transport behavior can be attributed to the photovoltaic and photoconductive effects. Moreover, the device shows photoresponsivity and detectivity up to 110 mA W−1 and 4.5 × 1013 Jones, respectively, under 532 nm laser illumination. This research unveils the charge transport mechanism of CsPbBr3 perovskite, provides more evidence and will thus contribute to the perovskite electronic and optoelectronic researches. [ABSTRACT FROM AUTHOR]

Single crystal perovskites are used in solar cells, photodetectors, and other devices due to their excellent light absorption and carrier transport characteristics. However, for light‐emitting applications, photoluminescence (PL) is usually weak for MAPbBr3 (MA = CH3NH3+) single crystals (MBSCs) compared with their polycrystalline counterpart. Therefore, developing novel techniques to process MBSCs with different morphologies for PL‐related applications is greatly needed. The current strategies for making perovskite crystals are mostly based on bottom‐up method (chemical synthesis and assembling). Here, an easy method to achieve top‐down fabrication of MBSCs, i.e., femtosecond laser processing MBSC surface by controlling the laser parameters is demonstrated. The femtosecond laser processing technology can achieve two orders of magnitude enhancement under ambient conditions in PL. In addition, the processed regions also show three times enhancement in PL under nitrogen environment. It is assumed that this is mainly due to the texture based on photon recycling and light out‐coupling mechanism, and the passivation of surface recombination centers on MBSC. This study not only provides a convenient top‐down strategy to achieve a range of morphological micro‐/nanostructures with enhanced PL on MBSC surface, but also paves the way for applications of MBSCs in light emitting or PL imaging devices. Developing novel techniques to process MAPbBr3 single crystals (MBSCs) with various morphologies for photoluminescence‐related applications is highly necessary. Multi‐morphological micro‐/nanostructures induced by a top‐down fabricating technology, i.e., femtosecond laser processing, are achieved on MBSC surfaces. Dramatically‐enhanced photoluminescence of two orders of magnitude in ambient conditions and three times in nitrogen atmosphere is demonstrated, which is promising for photoluminescence‐related applications. [ABSTRACT FROM AUTHOR]

Two issues are required to be solved to bring intrinsically self-healing polymer coatings into real applications: remote activation and satisfied practical properties. Here, we used MXene, a newly reported two-dimensional material, to provide an epoxy coating with light-induced self-healing capabilities and we worked to enhance the properties of that coating. The self-healing coatings had a reversible crosslinking network based on the Diels-Alder reaction among maleimide groups from bis(4-maleimidopheny)methane and dangling furan groups in oligomers that were prepared through the condensation polymerization of diglycidylether of bisphenol A and furfurylamine. The results showed that the delaminated MXene flakes were small in size, around 900 nm, and dispersed well in self-healing coatings. The MXene flakes of only 2.80 wt % improved greatly the pencil hardness of the coating hardness from HB to 5H and the polarization resistance from 4.3 to 428.3 MΩ cm−2. The self-healing behavior, however, was retarded by MXene flakes. Leveling agent acted a key part here to facilitate the gap closure driven by reverse plasticity to compensate for the limitation of macromolecular mobility resulting from the MXene flakes. The self-healing of coatings was achieved in 30 s by thermal treatment at 150 °C. The efficient self-healing was also demonstrated based on the recovery of the anti-corrosion capability. MXene flakes also played an evident photothermal role in generating heat via irradiation of near-infrared light at 808 nm and focused sunlight. The healing can be quickly obtained in 10 s under irradiation of near-infrared light at 808 nm having a power density of 6.28 W cm−2 or in 10 min under irradiation of focused sunlight having a power density of 4.0 W cm−2. [ABSTRACT FROM AUTHOR]