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We present a novel configuration of second-order topological photonic crystal (SOTPC) comprising interconnected dielectric material with elliptical air holes. Based on this SOTPC design, we construct a topological corner state (TCS) cavity and a topological edge state (TES) waveguide. Through the coupling of the TCS cavity with the TES waveguide, we establish a topological cavity-waveguide coupled system (TCWCS) that exhibits an ultrasharp asymmetric topological Fano resonance. Numerical simulations demonstrate that the proposed TCWCS achieves an exceptionally high quality factor exceeding 1 0 8 , surpassing previously reported results by several orders of magnitude. Moreover, the refractive index sensing application implemented with TCWCS shows a sensitivity of 278 nm/RIU and a figure of merit surpassing 1 0 7 1/RIU. Notably, our simulations reveal that the lineshape and quality factor of the Fano resonance, as well as the index sensing performance in the TCWCS, are highly robust against structural defects. The demonstrated capabilities of the TCWCS open up avenues for further exploration and development in the field of topological photonics based on our proposed SOTPC. • A novel type of second-order topological photonic crystal (SOTPC) is proposed. The coupled system based on SOTPC exhibits an ultrasharp topological Fano resonance. • An exceptionally high quality factor exceeding 1 0 8 is obtained, surpassing previously reported results by several orders of magnitude. • The performance of the Fano resonance shows significant robustness against structural defects. [ABSTRACT FROM AUTHOR]

Design of hollow carbon structure by using metal-organic-frameworks (MOFs) precursors has come under the spotlight in electrochemical energy related applications due to its structure advantages. Here, a bimetal-based MOF (Zn and Fe) is adopted to synthesize hollow carbon nanobox with encapsulation of FeP nanoparticles. An unique core-shell architecture consisting of Zn-Fe Prussian blue analogue (PBA) core and polydopamine shell is first synthesized, followed by pyrolysis-oxidation-phosphorization process to prepare monodispersed FeP nanoparticles encapsulated in hollow carbon nanobox (denoted as FeP/HCNB). Electrochemical hydrogen evolution activity is chosen to investigate the structure advantage of FeP/HCNB. It achieves overpotentials of −88 mV and −180 mV at 10 mA cm−2 in acidic and alkaline solutions, respectively, and continuous operation for 15 h (start at 20 mA cm−2). It is therefore expected that the synthetic strategy of nanobox would enlighten the preparation of various nanostructures for different applications. Image 1 [ABSTRACT FROM AUTHOR]

Abstract Water electrolysis is of great importance for high-efficient hydrogen production. Replacing noble metal-based electrocatalysts by highly efficient and inexpensive non-noble metal based catalysts is critical for the practical application of these technologies. Here we report a novel hybrid of nitrogen-doped carbon shell coated CoP nanocrystals encapsulated in porous nitrogen-doped carbon substrate (CoP/PNC), which is synthesized through sol-gel and consequent pyrolysis-oxidation-phosphorization method. The obtained CoP/PNC exhibits promising electrocatalytic performance toward HER and OER due to the synergistic effect between N-doped carbon and CoP nanocrystals. When the CoP/PNC catalyst is applied in a two-electrode water splitting device, the cell potential at 10 mA cm−2 could be as low as 1.68 V. Besides, it still remains current retention of 78.7% after continuous run for 24 h. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Pseudocapacitive charge storage has been regarded as a promising mechanism to achieve both high specific energy and power energy storage devices. Some pseudocapacitive anode materials show great high-rate performance, however, it remains a significant challenge to develop the cathode ones. Herein, for the first time, we report a layered iron vanadate (Fe 5 V 15 O 39 (OH) 9 ⋅9H 2 O, named as kazakhstanite) nanosheets (FeVO NSs) with featuring ultrathin layer thickness (< 10 nm). The FeVO NSs are synthesized by a facile wet-chemical approach with a high yield. Compared to the FeVO nanoparticles, the crystalline layered FeVO NSs have additional interlayered Li + storage sites, leading to the enhanced capacity. Ex-situ X-ray diffraction results demonstrate a non-phase change process and there is only ~ 1.1% layer expansion/shrinkage during lithiation and delithiation process. Based on detail kinetics analysis and ex-situ X-ray photoelectron spectroscopy results, it is found that over 70% of total capacity is pseudocapacitive contribution, which contributes to the ultrahigh-rate capability (a high capacity of 350, 273 and 90 mAh g −1 is achieved at 0.1, 1 and 20 A g −1 , respectively) and excellent cycling stability over thousands of cycles. This work presents the high performance vanadate material that delivers highly pseudocapacitive behavior, and provides a promising direction to realize both high energy and high power lithium storage. [ABSTRACT FROM AUTHOR]

[Display omitted] • A DNA repair enzyme (APE1) and magnetic dual-responsive theranostic nanosystem (FS@DNA-DOX) was obtained. • The nanosystem possesses a high specificity to the cancer cell-high expressed APE1 and effectively releases drugs in MCF-7 cells. • The nanosystem could effectively target to the tumor site and release drugs in MCF-7 cells. • In vivo experiments demonstrated the successful targeted drug delivery and strong tumor suppressor effects. • This dual-responsive theranostic nanosystem for chemotherapy increases the therapeutic effect as well as reduces the toxicity. Due to the high specificity and efficiency of enzymes, enzyme-responsive drug delivery systems are important in cancer therapy and diagnosis. Human apurinic/apyrimidinic endonuclease (APE1) is a representative DNA repair enzyme overexpressed in various cancer cells, which is also proven to be a promising stimuli in our previous studies. In this work, to realize targeted chemotherapy, an APE1 and magnetic dual-responsive nanocarrier was designed. The carrier is composed of Fe 3 O 4 @SiO 2 nanoparticles and specially designed AP-DNA strand that can be effectively hydrolyzed by APE1. The chemotherapeutic drug doxorubicin (DOX) was loaded onto the AP-DNA to form the theranostic nanosystem (FS@DNA-DOX). As the AP-DNA was parted under the hydrolysis of APE1 in cancer cells, DOX was released to inhibit tumor growth. In vitro experiment results indicated that the nanosystem possesses a high specificity to APE1 and effectively release DOX in MCF-7 cells. In vivo experiments demonstrated that the targeted delivery of the nanosystem to the tumor site was successfully achieved and that strong tumor suppressor effects were observed. Overall, the FS@DNA-DOX is a multifunctional and theranostic nanosystem for the chemotherapy of cancer by increasing the therapeutic effect as well as reducing the toxicity of drugs. [ABSTRACT FROM AUTHOR]

Abstract: Tissue factor (TF) has been implicated in the pathogenesis of various thrombotic disorders. Monoclonal antibodies (mAb) that specifically target TF may have potential as antithrombotic therapy. We designed a unique TF peptide (TFP) that was specific for the binding site to factor X (FX). This peptide was used to develop TF mAb that block the coagulation cascade by interfering with the combination of FX with the TF/FVIIa complex. Chemically synthesized TFP coupled to polylysine matrix was used as multiple antigenic peptide (TF-MAP) and this was used to immunize Balb/c mice for the preparation of hybridomas. One hybridoma cell line released an antibody, named TF4A12, which had high anticoagulant potency (by dilute prothrombin time assay). Western blotting showed that TF4A12 could bind TF-MAP and the soluble TF extracellular domain (sTF1–219). Results of FX activation assay and amidolytic activity assay showed that the anticoagulant ability of TF4A12 is due to blocking FX, but not FVII, binding to TF. Our study identified an efficient method of developing TF mAb that could block the coagulation cascade. [Copyright &y& Elsevier]

Abstract: A matrix is said to be bisymmetric matrix if for all . In this paper, an iterative method is constructed to find the bisymmetric solutions of matrix equation where is real matrices group. By this iterative method, the solvability of the matrix equation can be judged automatically. When the matrix equation is consistent, for any initial bisymmetric matrix group , a bisymmetric solution group can be obtained within finite iteration steps in the absence of roundoff errors, and the least norm bisymmetric solution group can be obtained by choosing a special kind of initial bisymmetric matrix group. In addition, the optimal approximation bisymmetric solution group to a given bisymmetric matrix group in Frobenius norm can be obtained by finding the least norm bisymmetric solution group of new matrix equation , where . [Copyright &y& Elsevier]

Abstract: A n × n real matrix P is said to be a real generalized reflection matrix if P T = P and P 2 = I. A n × n real matrix X is said to be a reflexive matrix with respect to the generalized reflection matrix P if X = PXP. In this paper, the concept of gradient matrix (∇F(X)) is presented and an algorithm is constructed to solve the reflexive with respect to the generalized reflection matrix P solution of the minimum Frobenius norm residual problem:. By this algorithm, for any initial reflexive matrix X 1, a solution X ∗ can be obtained within finite iteration steps in the absence of roundoff errors, and the solution X ∗ with least-norm can be obtained by choosing a special kind of initial reflexive matrix. In addition, in the solution set of above problem, the unique optimal approximation solution to a given matrix X 0 in Frobenius norm can be obtained by finding the least-norm reflexive solution of the new minimum residual problem: , where , . Given numerical examples show that the iterative method is quite efficient. [Copyright &y& Elsevier]

• Non-uniform electric field results in the variation of Cu2+/Cu+ ratio. • A two-layered structure was formed in the black area. • Both Cu species and Ca, P-rich compounds are crucial for biological performance. In the present work, a Cu-incorporated TiO 2 coating was successfully fabricated through a one-step micro-arc oxidation (MAO) of Ti in a solution containing 10 g/L ethylene diamine tetraacetic acid cupric disodium (Na 2 Cu-EDTA). Interestingly, different colour appearances of the resultant Cu-incorporated TiO 2 coating were noticed with the presence of black area at the edge and brown area in the centre. Further, microstructural characterization reveals that, unlike the central brown area with high amount of Cu+, the peripheral black area is mainly enriched in Cu2+, which exhibits a two-layered structure consisting of TiO 2 inner layer and porous Ca, P-rich outer layer containing nano-sized hydroxyapatite (HA) crystals. Finally, biological examination reveals that the peripheral black area exhibits both improved bone formability and enhanced antibacterial capability in comparison to the central brown area. Based on the observation, the coating formation mechanism is proposed, which provides valuable guidance for the utilization of MAO method in the field of bio-medical materials. [ABSTRACT FROM AUTHOR]

Solar photocatalytic hydrogen production shows promise in addressing global energy and environmental concerns. The limited efficiency of photocatalysts is mainly due to ineffective separation and transfer of photogenerated charges. To improve this, we enhance the TiO 2 –Ti 3 C 2 heterojunction by in-situ oxidation through interfacial engineering, resulting in a more compact composition. Subsequently, we anchor single-atom Pt at the TiO 2 –Ti 3 C 2 interface through photo-Ti 3 C 2 reduction. The in-situ growth of TiO 2 on Ti 3 C 2 introduces an interfacial driving force for carrier separation and provides a channel for electron transfer from TiO 2 to Ti 3 C 2. This further facilitates transfer onto Pt, shortening the migration distance and enhancing the photocatalytic efficiency. The best Pt/TiO 2 –Ti 3 C 2 composite demonstrates an impressive hydrogen precipitation efficiency of 767 μmol g−1 h−1, surpassing TiO 2 and Pt/TiO 2 by factors of 12 times and 1.46 times, respectively. Furthermore, we developed a higher efficiency photocatalyst using the molten salt method to avoid the risks associated with conventional hydrofluoric acid etching. This research opens up new possibilities for the preparation of MXenes interface-modified catalysts, offering a valuable avenue for future exploration in the field. • Ti 3 C 2 MXene was synthesized by F-free molten salt method. • TiO 2 –Ti 3 C 2 composites were successfully synthesized by in situ oxidation method. • Single-atom Pt interface engineered Pt–O electron transfer channel to shorten the charge migration distance. • TiO 2 –Ti 3 C 2 heterojunction interface Ti– O –Ti bridge promotes rapid electron transfer and separation. • Single-atom and heterojunction interface engineering synergistic effect to promote photocatalytic hydrogen production. [ABSTRACT FROM AUTHOR]

In the present work, Zn-incorporated TiO 2 coatings are prepared through a one-step micro-arc oxidation (MAO) method on a grade 4 pure titanium with the addition of either Na 2 Zn-EDTA solution or ZnO nanoparticles (NPs) as Zn sources. The microstructural features of both Zn-incorporated TiO 2 coatings were systematically examined. It is revealed that different Zn sources result in significant difference of phase component, chemical state, composition and morphology between the resultant Zn-incorporated MAO coatings. Zn species could be present as ZnO and Zn(OH) 2 in the coating when Na 2 Zn-EDTA was used as Zn source whereas the presence of ZnO nano-clusters is obvious on the coating surface with ZnO NPs as Zn source. The addition of ZnO NPs during the MAO process also leads to a lower Zn content of the resultant coating, which is more defective with increased thickness in comparison to that of Na 2 Zn-EDTA. Further, antibacterial property and osteogenic activity of both Zn-incorporated coatings were examined. Both Zn-incorporated coatings exhibit favourable bacterial inhibition ability and bone formability, suggesting the successful synthesis of bifunctional coatings through the facile one-step micro-arc oxidation method. [ABSTRACT FROM AUTHOR]

Abstract In the present work, a two-layer hydroxyapatite (HA)/Cu-doped TiO 2 composite coating was prepared via one-step micro-arc oxidation in an aqueous electrolyte containing calcium acetate, sodium di-hydrogen phosphate and ethylene diamine tetraacetic acid cupric disodium (CuNa 2 -EDTA) at a constant current density of 100 mA/cm2. After micro-arc oxidation for 20 min, Cu species incorporate into the TiO 2 as CuO and Cu 2 O, resulting in the formation of Cu-doped TiO 2 -based coating. In addition, spherical-shaped HA phase of nanometre scale is also present on the Cu-doped TiO 2 -based coating. With HA phase boosting osseointegration and Cu species killing pathogenic microbes, a bi-functional coating fabricated by one-step micro-arc oxidation is of promising potential application in the bio-medical field. [ABSTRACT FROM AUTHOR]

Integration of the published experimental data of partially melted amphibolite, orthogneiss, granite and aplite reveals the existence of three rapid strength drops of the rock-assemblage at melt fraction around 7%, 21% and 41% respectively. The first and the last drops are equivalent to the well-known ‘melt connectivity transition’ (MCT) and ‘solid to liquid transition’ (SLT). The drop at melt fraction around 21% is newly identified and termed as the ‘framework-melting transition’ (FMT). The FMT is defined as the transition from eutectic quartz-feldspars melting to refractory biotite melting. The three rheological transitions are well constrained by the geological data from the Fuhu profile in Guangdong Province, SE China. This profile is a 15 m high cliff. Rocks exposed on the profile are zoned as mottled, stripped, narrow-banded and wide-banded migmatites and diatexitic granite from the top of the profile downwards. The leucosome proportions of the zones measured on the outcrops combined with the experimental data of the partially melted rocks have significant implications for understanding the role of rheological transitions during crustal melting. The MCT, which corresponds to the boundary between the mottled and the narrow-banded migmatites, suggests the segregation of melt within the partially melted system along with the compaction of matrix. Thus, the MCT is deemed to be the transition of the partially melted system from matrix-supported (melt stored in pore-space) to framework-supported (melt stored in foliation/bedding-space of protolith). The FMT corresponding to the boundary between the narrow- and the wide-banded migmatites denotes the inception of melting of the solid framework. Mechanically, the FMT can be regarded as the transition of the framework from compaction to fusion, and geochemically, the transition from eutectic melting of quartz-feldspars to that of refractory biotite. The increasing melt due to framework-melting after the FMT is basically limited within the solid framework until the melt fraction exceeding the SLT. The SLT is geologically constrained by the in-situ metatexite-diatexite transition that is also termed as Magma Interface (MI). The SLT (MI) represents the upper limit of a crustal magma layer. Because of the downward increasing temperature and melt fraction, there should be no consecutive layer of felsic rock existed in the space between the SLT (MI) and the mafic lower crust except the isolated rock-blocks within the magma layer. [ABSTRACT FROM AUTHOR]

The traditional sol-gel process usually takes a long time to form a stable Cu 2 ZnSnS 4 (CZTS) sol-gel solution, which increases the whole process time. In this paper, an electrodeposition assisted sol-gel process was employed to reduce the solution preparation time. Cu was electrodeposited on Mo surface and ZnSnS sol-gel was rotated on Cu surface to prepare CZTS films. The solution preparation time was reduced from 12h to 30min. The mechanism of CZTS phase formation with sol-gel method assisted by electrodeposition was studied. Cu 3 SnS 4 phase was formed during the electrodeposition assisted sol-gel process, while Cu 2 SnS 3 phase was formed when the CZTS precursor during sol-gel process. Cu content was rich at the beginning of the reaction to form Cu 3 SnS 4 during the electrodeposited assisted sol-gel process. CZTS films with Cu/(Zn + Sn) of 0.84 and Zn/Sn of 1.03 were prepared by sol-gel method assisted by electrodeposition. Compared with CZTS films prepared by sol-gel method, CZTS films prepared by this method have larger and more uniform grains. It is also found that the thickness of MoS 2 layer was thinner than the one prepared by sol-gel method. • An electrodeposition assisted sol-gel method was employed to prepare CZTS films. • The solution preparation time was reduced from overnight to 30min. • The grains of CZTS films prepared by this method were larger and more uniform than the one prepared by sol-gel method. • Electrodeposited Cu helped to suppress the formation of MoS 2. [ABSTRACT FROM AUTHOR]

Abstract: The thermal expansion behavior of compressive stress aged Ti–50.7% Ni (atom fraction) alloy was investigated. The feasibility for preparing a Cu/TiNi composite with low coefficient of thermal expansion (CTE) through TiNi alloy was explored. Detached TiNi alloy strips were placed between two Cu plates, the assembly body was rolled at 800°C, then the Cu/TiNi composite was solution-treated followed by compressive stress aging. Due to the obvious mechanic joggle of the mating surfaces during hot rolling process and diffusion in the interface of Cu and TiNi alloy during solution treatment, the solution-treated and compressive stress aged Cu/TiNi composite exhibits a good interface bonding. It is found that compressive stress causes the parallel alignment of precipitate Ti3Ni4 during aging process, resulting in all-round shape memory effect and negative thermal expansion behavior of TiNi alloy in the temperature range approximately between −50 and 75°C. Therefore, the average CTE of the Cu/TiNi composite is greatly lowered by the negative CTE of its TiNi strips. Due to the connectivity of Cu and its excellent thermal conductivity, the Cu/TiNi composite possesses high thermal conductivity. [Copyright &y& Elsevier]