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[Display omitted] Apelin-13, a type of active peptide, can alleviate lipopolysaccharide (LPS)-induced acute lung injury (ALI). However, the specific mechanism is unclear. Cell cycle checkpoint kinase 1 (Chk1) plays an important role in DNA damage. Here, we investigated the regulatory effect of Apelin on Chk1 in ALI. Chk1-knockout and −overexpression mice were used to explore the role of Chk1 in LPS-induced ALI mice treated with or without Apelin-13. In addition, A549 cells were also treated with LPS to establish a cell model. Chk1 knockdown inhibited the destruction of alveolar structure, the damage of lung epithelial barrier function, and DNA damage in the ALI mouse model. Conversely, Chk1 overexpression had the opposite effect. Furthermore, Apelin-13 reduced Chk1 expression and DNA damage to improve the impaired lung epithelial barrier function in the ALI model. However, the high expression of Chk1 attenuated the protective effect of Apelin-13 on ALI. Notably, Apelin-13 promoted Chk1 degradation through autophagy to regulate DNA damage in LPS-treated A549 cells. In summary, Apelin-13 regulates the expression of Chk1 by promoting autophagy, thereby inhibiting epithelial DNA damage and repairing epithelial barrier function. [ABSTRACT FROM AUTHOR]

Photodetectors convert light into electrical signals and are crucial for scientific research and practical applications. Colloidal quantum dots (QDs) have emerged as a superior material for fabricating printable next-generation QD photodetectors, allowing facile fabrication, cost-effectiveness, and high flexibility. Their ability to detect a broad spectrum of signals, from high-energy to infrared signals, facilitates diverse technological applications, including medical imaging, security screening, environmental monitoring, and communication systems. Over recent years, a range of deposition techniques for printed QD-based photodetectors have been developed, covering a broad spectrum of photodetection applications. Significant efforts are being made to overcome the challenges associated with various deposition techniques, aiming to enhance the performance of QD-based photodetectors for specific spectra detection, therefore facilitating their practical deployment. This review aims to provide a clear understanding of the state-of-the-art developments in the field of printed QD-based photodetection in terms of the deposition techniques and different spectrum photodetectors. The review begins with the fundamental properties of colloidal QDs and their suitability for printable electronics. Subsequently, various deposition techniques and photodetector structures are explored, highlighting the advancements and applications of these QDs in broad-spectrum photon detection. Furthermore, we discuss the current challenges and potential solutions for the development of QD-based photodetectors. The findings and recommendations of this review are expected to inspire future research on printed QD-based photodetectors. [Display omitted] • Key properties of colloidal quantum dots for printable electronics. • Advances in deposition techniques and structures of colloidal quantum dots photodetectors for broad-spectrum detection. • Challenges and solutions in developing quantum dot-based photodetectors. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co 3 O 4 quantum dots/g-C 3 N 4 nanosheets with oxygen vacancies (Vo-CoCN) were synthesized. • Removal efficiency of SDz is up to 100 % and the mineralization rate was 77.4 % after 20 min in 0.25-Vo-CoCN/PMS system. • Oxygen vacancies promote the redox cycling of Co3+/Co2+ and the formation of •SO 4 - and 1O 2. • Possible SDz degradation mechanism and toxicity assessment in the system were proposed. Co 3 O 4 quantum dots /g-C 3 N 4 nanosheets nanomaterials with vacancies (V O -CoCN) were fabricated by deposition–precipitation and NaBH 4 reduction. TEM and HRTEM images indicated that Co 3 O 4 particles of about 2 nm size are uniformly distributed on the surface of the g-C 3 N 4 nanosheets. Furthermore, the formation of oxygen vacancies was also confirmed by HRTEM, XPS, ESR and other techniques. The 0.25-V O -CoCN catalyst coupled with peroxymonosulfate (PMS) exhibits excellent sulfadiazine (SDz) removal efficiency is up to 100 % in 20 min, with a mineralization rate of 77.4 %. The cycle stability of the 0.25-V O -CoCN catalyst was also significantly improved compared to CoCN samples without vacancies for PMS activation. Moreover, the 0.25-V O -CoCN/PMS system can maintain the efficient SDz removal rate in the presence of low-concentration inorganic anions (NO 3 –, HCO 3 – and Cl-) in the pH range of 5–9. The free radical quenching experiment and EPR characterization reveal that the •SO 4 - radicals and 1O 2 non-free radicals are the main reactive oxygen species of SDz degradation in the V O -CoCN/PMS system. The superior degradation performance is attributed to the fact that oxygen vacancies can promote the redox cycling of Co3+/Co2+, thereby increasing the formation of •SO 4 - and simultaneously promoting the formation of singlet oxygen species. [ABSTRACT FROM AUTHOR]

A suite of eight polyhalogenated carbazole (PHCZ) congeners were detected in sediments of the Jiaozhou Bay wetland. 3,6-dichlorocarbazole (36-CCZ), and 3,6-dibromocarbazole (36-BCZ) were detected in all samples. The concentrations of ΣPHCZs ranged from 6.9 to 33.4 ng/g dry weight (dw). The recovery of surrogate standard ranged from 85 to 109%. Significant relationships were found between the concentrations of 36-CCZ and those of the other three detected compounds (36-BCZ, 36-ICZ, and 1368-BCZ). However, with regard to the other chemicals, only 1368-BCZ was related to 36-ICZ. The toxic equivalent (TEQ) was used to assess the relative toxicity of PHCZs, which ranged within 0.1–3.9 pg TEQ/g dw in sediment. The inventory of ΣPHCZs was 58.9 kg. These results indicate that PHCZs are widely distributed in the Jiaozhou wetland and the dyeing and finishing industries may be important contamination sources of PHCZs. • PHCZs are widely detected in sediment of the Jiaozhou Bay wetland. • Dyeing and finishing industry might be important contamination source of PHCZs. • There was relatively high TEQ of PHCZs in Jiaozhou Bay wetland. [ABSTRACT FROM AUTHOR]

The effects of time, temperature, and salinity on the adsorption of Tonalide (AHTN), Musk Xylene (MX), Galaxolide (HHCB), and Musk Ketone (MK) by microplastics of polyethylene (PE) and polyvinyl chloride (PVC) are studied. Results indicate that the equilibrium sorption time was about 10 h and the adsorption kinetics model conformed to the first-order adsorption kinetic model and pseudo-second order kinetic model, this indicates that the main adsorption mechanism might be chemical adsorption and physical absorption. Adsorption reached a nadir at 15 °C and 14% salinity. The adsorption capacity gradually increases, and then decreases, finally increases with an increase in NaCl concentration. Due to the specific surface area and the pore volume of PVC was larger than PE, the adsorption capacity of PVC was higher than that of PE in the equal conditions. • Equilibrium sorption times were 10 h for both PVC and PE. • Adsorption reached a nadir at 15 °C and 14% salinity. • The maximum adsorption capacity was at 25 °C. • The main adsorption mechanism might be chemical adsorption and physical absorption. • The adsorption capacity of PVC was higher than that of PE in the equal conditions. [ABSTRACT FROM AUTHOR]

Abstract Since hole transport materials (HTMs) play a significant role in enhancing the power conversion efficiency (PCE) and stability of perovskite solar cells (PSCs), which are the key factors for their commercialization, an effective design strategy is necessary for the potential HTMs in the current emerging field of PSCs. Here, we present a new class of HTM with pyridine as a central core with an extended π-conjugated molecular structure with electron-donating blocks. We have systematically investigated its photophysical, thermal, electrochemical, and charge transport properties and found that 4,4′-(5,5′-(pyridine-2,6-diylbis(4,1-phenylene))bis(thiophene-5,2-diyl))bis(N , N -bis(4-methoxyphenyl)aniline) (PyThTPA) is a potential HTM candidate for making PSCs. The PyThTPA HTM-based PSC attained an average PCE of 16.57% with outstanding long-term durability of over 720 hrs with minimal reduction of its initial PCE and negligible hysteresis. This PSC performance was 34% higher than that of the state-of-the-art HTM, Spiro-OMeTAD with tris(pentafluorophenyl)borane (BCF). We speculate that the Lewis acid-base adduct (LABA) formation of pyridine in the HTM and BCF interacted with methylammonium lead iodide (MAPbI 3), resulting in the MAPbI 3 /HTM interface becoming more selective for holes. This also enhanced the film uniformity and afforded a smoother morphology with improved hydrophobicity that further increased the long-term durability. Furthermore, the mobility and conductivity were increased for PyThTPA with BCF. To the best of our knowledge, this is the first report of pyridine being incorporated into the HTM with continuous π-conjugation and with a high performance of nearly 17%. Overall, we believe that this approach will be an effective design strategy capable of enhancing the performance of PSCs with less hysteresis and improved long-term durability. Graphical abstract fx1 Highlights • A new class of Lewis acid-base adduct-type hole transport material (HTM) is reported. • It exhibited an impressive performance in perovskite solar cells with outstanding long-term durability. • The average PCE was 34% higher than that of the state-of-the-art HTM, without any hygroscopic additives/dopants. • The MAPbI 3 /HTM interface became more selective for holes due to Lewis acid-base adduct formation of pyridine in HTM and BCF. • The mobility and conductivity were enhanced and the film was uniform with smooth morphology and improved hydrophobicity. [ABSTRACT FROM AUTHOR]

Abstract Microplastics and organic pollutants are typical contaminants in the marine environment. However, little is known about their interactions. In this study, the sorption of 3,6-Dibromocarbazole(3,6-BCZ) and 1,3,6,8-Tetrabromocarbazole (1,3,6,8-BCZ) by Polypropylene microplastic in simulated seawater was studied. Factors, including particle size, salinity and concentration, were investigated, and the experimental results were simulated using a mathematical model. Results showed that the pseudo-second-order kinetic model was more suitable to describe the sorption of polyhalogenated carbazole by microplastics, with equilibrium sorption times of 6 h and 8 h for 3,6-BCZ and 1,3,6,8-BCZ, respectively. Sorption capacity increased with decreasing particle size and the adsorption capacity increased initially and then decreased with increasing salinity, with a maximum sorption occurring at salinity of 14%. Moreover, the sorption amount increased with the increasing concentration of polyhalogenated carbazole. The sorption isotherms were confirmed as the extended Langmuir model and the extended Freundlich model, both of which were S-type. Graphical abstract Unlabelled Image Highlights • Pseudo-second-order kinetic model is suitable to describe the adsorption. • Extended Langmuir and Freundlich model are S-type. • The combined effect of microplastics and halogenated carbazole may negatively affect the marine ecological environment. [ABSTRACT FROM AUTHOR]

Highlights • To achieve a high sensitivity, the cascaded two Fabry-Perot interferometers sensor with the Vernier effect was proposed. • For the intensity interrogation, the sensor system only required a broadband light source and the photo detector. • The reaction between the Streptomycin monoclonal antibody and Streptomycin-BSA was measured by the sensor for the biosensing application. Abstract In this paper, a novel high-sensitivity optical sensor based on cascaded two Fabry-Perot interferometers (FPIs) has been investigated theoretically and experimentally. In order to improve the sensitivity, the two FP interferometers were designed with slightly different free spectrum ranges (FSRs) to produce Vernier effect. The experimental results showed that the sensitivity of the sensor is 23,794.6 nm/RIU for the wavelength interrogation and 4602.3 dB/RIU for the intensity interrogation, much higher than that of the conventional sensors for the bulk refractive index (RI) sensing. Finally, the reaction between Streptomycin monoclonal antibody and Streptomycin-BSA was measured, showing a great potential for low-cost and portable systems in biochemical sensing. [ABSTRACT FROM AUTHOR]

A combination of chemotherapy and phototherapy has emerged as a promising strategy for cancer treatment. To achieve effective combinational therapy of cancer with reduced toxicity, it is highly desirable to improve the targeting of chemotherapeutic and near-infrared photosensitizers to enhance their accumulation in tumor. Here we report a novel tumor targeting cell membrane capsule (CMC), originate from living cells, to load doxorubicin hydrochloride (DOX) and indocyanine green (ICG), for combinational photo-chemotherapy against cancer. As a result, folic acid modified CMC (CMC-FA, with a diameter about 200 nm and a FA density of 0.4 molecule/nm 2 ) showed 3–4 fold higher cell uptake by cancer cells in vitro and 2.3 times higher accumulation in mouse cancer xenografts in vivo than pristine CMC. DOX and ICG with therapeutically significant concentrations can be sequentially encapsulated into CMC-FA by temporary permeating the plasma membranes with high efficiency. The systematic administration of cancer targeting CMC-FA loaded with DOX and ICG could significantly inhibit tumor growth in mouse xenografts in the presence of a near-infrared light at 808 nm, without noticeable toxicity. These findings suggest that cancer targeting CMC may have considerable benefits in drug delivery and combinational cancer therapy. Statement of Significance A combination of chemotherapy and photothermal/photodynamic therapy has emerged as a promising strategy for cancer therapy. In current study, a novel cancer targeting cell membrane capsule (CMC-FA), originate from living cells and surface modified with folic acid, was developed to load doxorubicin hydrochloride (DOX) and indocyanine green (ICG), for combinational photo-chemotherapy against cancer. The systematic administration of drug loaded CMC-FA can significantly inhibit tumor growth in mouse xenografts in the presence of a near-infrared light at 808 nm, without noticeable toxicity. This study provides a simple and robust strategy to develop biocompatible therapeutic cell membrane capsules, holds strong translational potential in precise cancer treatment. [ABSTRACT FROM AUTHOR]

Cirsitakaoside is a natural compound isolated from Premna szemaoensis . However, the anti-inflammatory effects of cirsitakaoside are poorly understood. We investigated the anti-inflammatory action of cirsitakaoside in lipopolysaccharide (LPS)-stimulated macrophages and mice in vivo. Cirsitakaoside could suppress the production of pro-inflammatory cytokines such as interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) in a dose-dependent manner in LPS-stimulated mouse peritoneal macrophages and RAW264.7 cells. Cirsitakaoside also could inhibit inducible nitric oxide synthase (iNOS) mRNA and cyclooxygenase-2 (COX-2) mRNA expression in LPS-stimulated mouse peritoneal macrophages and RAW264.7 cells. These effects were partially carried out by inactivated nuclear factor-κB (NF-κB) and Mitogen-activated protein kinases (MAPKs) pathway via inhibiting the phosphorylation of the IKKα/β, IκBα and c-Jun N-terminal kinase/stress-activated protein kinase (JNK) in LPS-stimulated murine macrophages. In vivo, we showed that cirsitakaoside could relieve LPS-induced inflammation response. These results suggest that cirsitakaoside has the potential anti-inflammatory effect for treatment of inflammation diseases. [ABSTRACT FROM AUTHOR]

In this paper, we firstly prove that the absorption law for one-sided inverses along an element holds, and derive the absorption law for the inverse along an element. We then obtain the absorption law for the inverse along different elements. Also, we prove that a left inverse of a along d coincides with a right inverse of a along d , provided that they both exist. Then, the reverse order law and the existence criterion for the inverse along an element are given by centralizers in a ring. Finally, we characterize the Moore–Penrose inverse of a regular element by one-sided invertibilities in a ring with involution. [ABSTRACT FROM AUTHOR]

Thermo-responsive graphene-polymer films have been obtained by the modification of large CVD graphene films with pyrene-terminated poly( N -isopropylacrylamide) (PNIPAAm) via non-covalent π-π stacking interactions. Pyrene-terminated PNIPAAm was prepared by reversible addition fragmentation chain transfer (RAFT) polymerization using a pyrene-functionalized RAFT agent. Since PNIPAAm possesses a lower critical solution temperature (LCST) of 32 °C, the as-prepared graphene-PNIPAAm films could be reversibly deformed as a result of the morphology response of PNIPAAm to the environmental temperature variation. In addition, the thermo-triggered deformation of the graphene-PNIPAAm films was observed to be reversible and controllable by manipulation of the environmental temperature. Atomic force microscopy (AFM) and high-resolution SEM analysis evidenced the successful attachment of the PNIPAAm on the graphene surface. The thickness of the polymer was revealed by high-resolution scanning electron microscopy (SEM). The successful stepwise fabrication of the CVD graphene-polymer composite films was also characterized using Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). These thermo-responsive composite films would be highly desirable for a wide range of applications, such as thermo-responsive actuators, a thermo-responsive intelligent switch was fabricated using these thermo-responsive graphene composite films. [ABSTRACT FROM AUTHOR]

Keratin wastes are an important source of renewable raw material. Regenerated wool keratin is a promising natural material for tissue engineering. In the present study, l -cysteine redox method was performed to extract keratin from wool and the nanonets fabricated by one-step electrospinning of Poly (ε-caprolactone) (PCL) and wool keratin were presented here. The resulting nanofiber mats showed two parts of structures: randomly oriented nanofibers in diameter of 299–624 nm and dense nanonets in diameter of 25 ± 5 nm. The forming and coverage of nanonets was mainly affected by the addition of wool keratin and the relative humidity. With the addition of keratin, the hydrophilic nanonets can be successfully fabricated, where the water contact angles decreased around 20–50 degree compared to that of the pure PCL nanofibers. [ABSTRACT FROM AUTHOR]

Induction of type I interferon is a fundamental cellular response to viral infection. Interferon regulatory factor 3 (IRF3) plays an essential role in Toll-like receptor (TLR) and retinoic acid–inducible gene I (RIG-I) mediated induction of type I interferon and host antiviral responses. However, posttranslational regulation of IRF3 remains to be fully understood. In this study, we identified E3 ubiquitin ligase Casitas B-lineage lymphoma (c-Cbl) as a negative regulator for IRF3 protein stability and IFN-β signal pathway. Knockdown of c-Cbl expression by small interfering RNA enhanced virus-induced IFN-β production as well as cellular antiviral response, whereas overexpression of c-Cbl inhibited virus-induced IFN-β signaling. Coimmunoprecipitation experiments demonstrated that c-Cbl interacted with IRF3 via TKB domain of c-Cbl and IRF association domain of IRF3, promoting K48-linked polyubiquitination and proteasomal degradation of IRF3. Therefore, our findings suggest that c-Cbl negatively regulates IFN-β signaling and cellular antiviral response by promoting IRF3 ubiquitination and degradation, providing a new mechanism for control of type I interferon induction. [ABSTRACT FROM AUTHOR]

Chemical vapor deposition (CVD) has recently been considered as the most reliable method to prepare high-quality monolayer graphene films, yet the as-grown graphene usually contains wrinkles and cracks or suffers from discontinuity. These defects can easily result in the shredding of large-sized graphene into small pieces even under a gentle disturbance. Herein, this work presents a cost-effective new method to produce high-quality GQDs by vigorous sonication of defective CVD graphene. The prepared GQDs can be easily and stably dispersed in organic solvents. Morphology and optical properties of the GQDs are investigated using a number of techniques. And we observed the as-prepared GQDs are highly homogeneous, mostly consisted of single-layered graphene, roughly round shapes less than 8 nm in a diameter, and exhibited a strong blue luminescence. Impressively, it is also confirmed that the as-obtained GQDs can act as a promising light absorption material for phototransistor with a hybrid film of GQDs and indium gallium zinc oxide (IGZO) as the channel layer. The GQD/IGZO phototransistor exhibited an appreciated photocurrent, which is 10 times larger than that of the IGZO one when exposed to 270 nm light. [ABSTRACT FROM AUTHOR]

Herein, a uniform three-dimensional (3-D) graphene nanodots-encaged porous gold electrode was prepared via ion beam sputtering deposition (IBSD) and mild corrosion chemistry for efficient enzyme electrode fabrication. Enzymes, like glucose oxidase and catalase, were modified with pyrene functionalities and then loaded into the graphene nanodots encaged porous gold electrode via non-covalent π–π stacking interaction between pyrene and graphene. The fabricated enzyme electrodes showed profound reusability and repeatability, high sensitivity, inherent selectivity and enhanced detection range. As for glucose analysis a broad linear range from 0.05 to 100 mM was obtained and the linear range for hydrogen peroxide was 0.005 to 4 mM. Detection limits of 30 μM for glucose and 1 μM for hydrogen peroxide were achieved ( S / N = 3), respectively. These electrodes can be applied to analyze the clinical samples with reliable results. The formation mechanism and 3-D structure of the porous electrode were investigated using high resolution transmission electron microscope (HRTEM), atomic force microscopy (AFM), scanning electron microscope (SEM) and electrochemical impedance spectroscopy (EIS). Most importantly, various other ideal biosensors can be fabricated using the same porous electrode and the same enzyme modification methodology. [ABSTRACT FROM AUTHOR]

Let R be a ring with an involution ⁎ and p , a , q ∈ R . In this paper, we investigate the necessary and sufficient conditions for paq to have a { 1 , 3 } -inverse (respectively, { 1 , 4 } -inverse). In particular, the equivalences for the existence of the Moore–Penrose inverse of paq are obtained. As applications, the existence and expression of the Moore–Penrose inverse of a ( 2 , 2 , 0 ) matrix over R are given. [ABSTRACT FROM AUTHOR]

A graphene nanodots-encaged porous gold electrode via ion beam sputtering deposition (IBSD) for electrochemical sensing is presented. The electrodes were fabricated using Au target, and a composite target of Al and graphene, which were simultaneously sputtered onto glass substrates by Ar ion beam, followed with hydrochloric acid corrosion. The as-prepared graphene nanodots-encaged porous gold electrodes were then used for the analysis of heavy metal ions, e.g. Cu 2+ and Pb 2+ by Osteryoung square wave voltammetry (OSWV). These porous electrodes exhibited enhanced detection range for the heavy metal ions due to the entrapped graphene nanodots in 3-D porous structure. In addition, it was also found that when the thickness of porous electrode reached 40 nm the detection sensitivity came into saturation. The linear detection range is 0.009–4 μM for Cu 2+ and 0.006–2.5 μM for Pb 2+ . Good reusability and repeatability were also observed. The formation mechanism and 3-D structure of the porous electrode were also investigated using scanning electron microscope (SEM), transmission electron microscope (TEM) and X-ray photoelectron spectra (XPS). This graphene entrapped 3-D porous structure may envision promising applications in sensing devices. [ABSTRACT FROM AUTHOR]

In this paper, we study representations of the Moore–Penrose inverse of a 2 × 2 matrix M over a * -regular ring with two term star-cancellation. As applications, some necessary and sufficient conditions for the Moore–Penrose inverse of M to have different types are given. [ABSTRACT FROM AUTHOR]

• Cirsitakaoside has potent antiviral effect on VSV infected macrophages. • Cirsitakaoside promotes VSV-induced type I IFN production and inhibits pro-inflammatory cytokines production. • Cirsitakaoside promotes VSV-induced antiviral signaling pathway activation. • Cirsitakaoside protects mice from infection with VSV and relieves VSV-induced inflammatory response in vivo. Cirsitakaoside, isolated and purified from the stems and leaves of Premna szemaoensis and Macaranga denticulata, is a natural compound with potential anti-inflammatory effects. However, the role of Cirsitakaoside in antiviral activity and the underlying mechanism remains largely unknown. In this study, we aimed to identify whether Cirsitakaoside has antiviral activity and investigated the underlying mechanisms. Mouse peritoneal macrophages were pretreated with Cir or DMSO, and then infected by Vesicular Stomatitis Virus (VSV) for indicated hours, Q-PCR and ELISA were used to detect the expression of interferons and pro-inflammatory cytokines, immunoblot assay were employed to investigate the involved signaling pathway in the antiviral effects of Cirsitakaoside. Furthermore, mice infected with VSV were used to investigate the antiviral activities of Cirsitakaoside in vivo. Our study demonstrated that Cirsitakaoside could promote type I IFN expression and inhibit pro-inflammatory cytokines such as IL-6 and TNF-α production in mouse peritoneal macrophages infected by VSV. Suppressive viral replication effects of Cirsitakaoside were observed on VSV-infected mouse peritoneal macrophages as well. Furthermore, Cirsitakaoside significantly increased the VSV-triggered phosphorylation of TBK1, IRF3 and reduced the phosphorylation of IκBα and p65 in mouse peritoneal macrophages. in vivo , the results showed that Cirsitakaoside-treated mice were more resistant to VSV infection by producing more IFN-β and less pro-inflammatory cytokines. Our study indicates that Cirsitakaoside is a good candidate for the treatment of viral infection and inflammation-related diseases. [ABSTRACT FROM AUTHOR]

• 2D/2D TiO 2 /g-C 3 N 4 heterostructure was constructed by a facile hydrothermal method. • Tight ultrathin 2D heterostructure can shorten the migration distance of photogenerated carriers. • The exposed oxygen vacancy can expand light absorption and improve charge separation. Constructing two-dimensional (2D) heterostructure is an effective method to obtain highly efficient photocatalysts. In this work, 2D/2D TiO 2 /g-C 3 N 4 heterostructures were constructed via in-situ growth of TiO 2 nanosheets on the surface of g-C 3 N 4 nanosheets by a facile hydrothermal co-assembly technique. The increased dispersion is favorable to expose more vacancies, which is beneficial to the enhancement of visible light absorption. This unique 2D/2D heterostructure exhibits ultrathin thickness and larger interfacial contact area, which results in shorter migration distance of photo-generated carriers to the surface and faster participation in photocatalytic water splitting. As expected, the optimized TiO 2 /g-C 3 N 4 nanocomposites showed a higher photocatalytic hydrogen evolution performance under visible light irradiation than that of pristine g-C 3 N 4 and TiO 2 nanosheets. The improved performance can be attributed to the ultrathin nanosheet structure, the intimate interfacial contact and the presence of surface oxygen vacancies. More appealingly, this environment-friendly 2D/2D TiO 2 /g-C 3 N 4 nanohybrid would attract more attention in water splitting. [ABSTRACT FROM AUTHOR]

Metal matrix alloying is an effective modification strategy to introducing an interfacial carbide at the Cu/diamond interface for improving thermal conductivity of Cu/diamond composite. However, the distribution and diffusion of C and alloying elements in Cu/diamond composite are still unclear. Here, transmission electron microscopy was utilized to characterize the microstructure of Cu/diamond interface and an atom probe tomography nanotip of the Cu–B/diamond composite was successfully prepared. For the first time, we give a clear distribution of C and alloying elements in a Cu–B/diamond composite. The formation of B 4 C is the consequence of C and B atoms diffusing to the Cu/diamond interface. The solubility of B in Cu is confirmed to be 0.06 at.% at room temperature. The extremely low solubility (<4.8 ppm) of C in Cu limits the reaction between C and B, and thus a B-rich and C-free area is formed between Cu and B 4 C. The residual C and B atoms are accumulated at the Cu boundaries, forming carbides after the Cu matrix solidifies. The presence of solid-solution atoms and carbides at the Cu boundaries decreases the thermal conductivity of the Cu matrix and further the Cu–B/diamond composite. The findings provide insights into the formation of interfacial carbide and the regulation of thermal conductivity in Cu/diamond composite modified by metal matrix alloying methods. [ABSTRACT FROM AUTHOR]

Nanocrystalline oxide-dispersion-strengthened (ODS) alloys have recently been demonstrated with good thermal stability, improved radiation tolerance and high-temperature oxidation resistance. Here, we report the superior elevated-temperature creep resistance of a nanocrystalline 14YWTZ ferritic ODS alloy developed by our research group, which outperforms nearly all previously reported nuclear structural alloys, especially under reasonably high applied stresses (350 ∼ 450 MPa, 650 °C). Mechanical testing and detailed microstructural analysis clearly reveal that high-density nanoprecipitates and multi-component grain boundary (GB) co-segregation can highly stabilize the nanocrystalline microstructure, changing the creep mechanism from conventional GB mediated deformation of nanocrystalline materials to a dislocation climb dominated process. Meanwhile, the stable nanoprecipitates can effectively hinder dislocation/sub-grain boundary movements, thus further retarding the dynamic recovery/recrystallization softening during the high-stress creep. This family of microstructurally stable nanocrystalline ODS alloys show good potential as high-performance structural materials candidates applicable to extremely hostile conditions in future advanced nuclear reactors. [Display omitted] [ABSTRACT FROM AUTHOR]

• the mechanism of molecular emission spectrum enhancement. • femtosecond and nanosecond double-pulse laser ablation. • strengthening signal intensity and improving analysis sensitivity. The spectral emission of molecules is important for determination of some elements or for isotopic analysis. However, laser ablation molecular emission spectroscopy is usually limited by low sensitivity and high detection limits. Here, femtosecond (fs)-nanosecond (ns) double-pulse laser in the orthogonal geometry was performed to ablate the aluminum target in air. As ns laser pulse delayed the fs laser pulse, the AlO B2Σ+-X2Σ+ emission spectral intensity first increased and then weakened. The optimal enhancement of molecular emission occurred during the second ns laser ablation aerosol particles (formed after the fs laser induced plasma extinguished). The evolution of AlO emission with different fs-ns inter-pulse times was discussed, which was related to whether the aluminum plasma induced by the fs laser pulse expanded to the ns laser focus position and whether the plasma was extinguished, before the ns laser pulse excitation. The influence of the number of ablation laser pulses on the molecular spectrum intensity distribution was also studied, which was found to be attributed to crater effect by fs laser ablation. These results are helpful to deeply understand the mechanism of molecular spectral emission enhanced by double-pulse laser ablation. [ABSTRACT FROM AUTHOR]

Doping B/C inhibit O segregation at GB and dramatically improve mechanical properties via GB engineering. [Display omitted] Refractory high-entropy alloys (RHEAs), particularly NbMoTaW RHEAs, exhibit outstanding softening resistance and thermal stability at ultra-high temperatures, but suffer from room-temperature brittleness, which severely limits their processability and thus practical application. In this study, we successfully achieved large plasticity of >10%, along with high strength of >1750 MPa in the NbMoTaW RHEAs via grain boundary engineering with the addition of either metalloid B or C. It was revealed that the room-temperature brittleness of the as-cast NbMoTaW RHEA originates from the grain-boundary segregation of the oxygen contaminant which weakens grain-boundary cohesion. The doped small-sized metalloids preferentially replace oxygen at grain boundaries and promote stronger electronic interaction with the host metals, which effectively alleviates the grain boundary brittleness and changes the fracture morphology from intergranular fracture to transgranular fracture. Our findings not only shed light on the understanding of the embrittlement mechanism of RHEAs in general, but also offer a useful route for ductilization of brittle HEAs. [ABSTRACT FROM AUTHOR]