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Due to its high theoretical capacity and appropriate potential platform, tin-based alloy materials are expected to be a competitive candidate for the next-generation high performance anodes of lithium-ion batteries. Nevertheless, the immense volume change during the lithium-ion insert process leads to severe disadvantages of structural damage and capacity fade, which limits its practical application. In this work, a three-dimensional (3D) multicore-shell hollow nanobox encapsulated by carbon layer is obtained via a three-step method of hydrothermal reaction, annealing and alkali etching. During the electrochemical reactions, the CoSn@void@C nanoboxes provide internal space to compensate the volumetric change upon the lithiation of Sn, while the inactive component of Co acts as chemical buffers to withstand the anisotropic expansion of nanoparticles. Owing to the above-mentioned advantages, the elaborated anode delivers an excellent capacity of 788.2 mAh/g at 100 mA/g after 100 cycles and considerable capacity retention of 519.2 mAh/g even at a high current density of 1 A/g after 300 cycles. The superior stability and high performance indicate its capability as promising anodes for lithium-ion batteries.

The compressive mechanical behavior of composite modified double base (CMDB) propellant was investigated across a wide scope of strain rates ranging from 10-3 s-1 to 4210 s-1 at room temperature, by applying a conventional universal testing machine and a split Hopkinson tension bar (SHPB), respectively. The derived stress-strain curves at different strain rates show a strong rate dependence, indicated that yield stress, ultimate stress and strain energy density of CMDB propellant all increase with strain rate by following a power law function, while the amplification of increase are different. The deformation and damage modes of CMDB propellant has changed from a typical ductile manner (cracking along the axial direction) to a brittle manner (maximum shear failure) with increasing of strain rate. Scanning electron microscopy (SEM) was employed to explore the microscopic failure characteristics of CMDB propellant. Under quasi-static loading, the nearly parallel micro-cracks propagating along the axial direction and the debonding of RDX particle without particle crushing can be observed. While under dynamic loading, the micro-crack is 45° angle to the axial direction, and multiple cracking modes of RDX particles appeared. Finally, the correlation between strain energy density and failure mechanisms of CMDB propellant was revealed by developing four characteristic failure modes. The findings of this study is very important to evaluate the structural integrity of CMDB propellant.

Chiral molecules are widely prevalent in nature and biological systems, and artificial chiral nanoparticles have drawn enormous interest owing to their unique optical and physical properties. Howev...

Macromolecule nanocrystal network and strong interfacial interaction are always beneficial to enhance the mechanical property of polymer-based nanocomposites. Poly (vinyl alcohol) (PVA), a typical biocompatible semicrystalline polymer, is an ideal candidate for preparing high performance polymer-based nanocomposites. However, the rich hydrogen bonds between PVA matrix and graphene oxide (GO) can disrupt the formation of PVA nanocrystal network. Thus, it remains a great challenge to achieve both strong and tough PVA-GO nanocomposites. Herein, by introducing a novel Janus-like amphiphilic graphene oxide (JGO), both of hydrogen bonding and interfacial crystallization have been constructed between JGO sheets and PVA matrix. Benefiting from amphiphilic interfacial interaction and the enhanced crystal network, both PVA-JGO dried films and their swollen hydrogels films show superior mechanical properties than those of traditional PVA-GO nanocomposites. PVA-JGO dried films exhibit a 264% improvement of toughness at a JGO loading of 1wt%. Meanwhile, the corresponding PVA-JGO swollen hydrogel films display simultaneous improvement of nearly 8 times increase of tensile strength and 20 times increase of toughness compared to traditional PVA-GO nanocomposite. This work indicates multiple interfacial interactions and macromolecule crystal networks can be concurrent in PVA nanocomposites by innovative modification of nanofillers, providing a new strategy to construct PVA nanocomposites with high strength and high toughness. The integration of outstanding mechanical and swelling resistance properties on PVA-JGO nanocomposite films render their promising applications, such as packaging and toughening hydrogel materials.

Anodic oxygen evolution reaction (OER) is the key bottleneck for water electrolysis technique owing to its sluggish reaction kinetics. Interfacial engineering on the rationally designed heterostructure can regulate the electronic states efficiently for intrinsic activity improvement. Here, we report a co-phosphorization approach to construct a VPO4-Ni2P heterostructure on nickel foam with strongly chemical binding, wherein phosphate acts as electronic modifier for Ni2P electrocatalyst. Profiting from the interfacial interaction, it is uncovered that electron shifts from Ni2P to VPO4 to render valence increment in Ni species. Such an electronic manipulation rationalizes the chemical affinities of various oxygen intermediates in OER pathway, giving a substantially reduced energy barrier. As a result, the advanced VPO4-Ni2P heterostructure only requires an overpotential of 289 mV to deliver a high current density of 350 mA/cm2 for OER in alkaline electrolyte, together with a Tafel slope as low as 28 mV/dec. This work brings fresh insights into interfacial engineering for advanced electrocatalyst design.

We develop the effective modification strategy based on molecular engineering of s-triazine and its derivatives to improve the photoelectric performance of all-inorganic perovskites (AIP) for the first time. The surface modification strategy with cyanuric acid successfully increases the PLQY of AIP from 40.55% to 88.15%, and significantly enhances the current of the AIP film under 3 V by almost 20-fold (from 4.44 mA to 81.20 mA). This work has proven the effectiveness of improving the photoelectric performances of AIP via s-triazine and its derivatives and also suggested the potential risks of reducing the photoelectric performance of AIP due to inappropriate substituents in conjugated organic ligands.

Magnetic field shields are important for electronic equipment, ultrahigh-sensitivity sensors, and electrical instruments. For ultrahigh-sensitivity atomic sensors, in particular, ferrite shields with low intrinsic magnetic noise are widely used. In this article, the calculation methods of longitudinal and transverse magnetic noise, which are calculated by loss, are analyzed. The experimental results confirm the feasibility of the model. Using the loss separation method, it is proved that the loss of ferrite magnetic shielding is mainly hysteresis loss, which is below 100 Hz. To effectively reduce the magnetic noise, we analyze the effect of structure parameters on the longitudinal and transverse magnetic noise, and the optimized parameters are obtained. The results show that the longitudinal magnetic noise decreases with the increasing aspect ratio and stabilize eventually. When the aspect ratio exceeds 1, the transverse magnetic noise remains practically unchanged. When the external diameter is fixed, by optimizing the thickness of the magnetic shield, the optimal solution for the longitudinal and transverse magnetic noise is obtained.

The emitted noise and vibration induced by the unsteady flow of the centrifugal pump are always focused during its running, which is also associated with the high amplitude pressure pulsations. How to reduce pressure pulsations remains a crucial problem for the researcher considering low noise design of the centrifugal pump. In the current research, a special staggered impeller is proposed to reduce intense pressure pulsations of a centrifugal pump with ns = 69 based on alleviating rotor‐stator interaction. The numerical simulation method is conducted to illustrate the influence of staggered impeller on the pump performance and pressure pulsations, and three typical flow rates (0.8ФN–1.2ФN) are simulated. Results show that the staggered impeller will lead to the pump head increasing, and at the design working condition, the increment reaches about 3% compared with the original impeller. Meanwhile, the pump efficiency is little affected by the staggered impeller, which is almost identical with the original impeller. From comparison of pressure spectra at 20 monitoring points around the impeller outlet, it is validated that the staggered impeller contributes significantly to decreasing pressure pulsations at the concerned working conditions. At the blade passing frequency, the averaged reduction of 20 points reaches 89% by using the staggered impeller at 1.0ФN. The reduction reaches to 90%, 80% at 0.8ФN, 1.2ФN, respectively. Caused by the rib within the staggered impeller, the internal flow field in the blade channel will be affected. Finally, it is concluded that the proposed staggered impeller surely has a significant effect on alleviating intense pressure pulsation of the model pump and does not obviously alter the global performance of the pump, which is very promising during the low noise pump design considering its feasibility for manufacturing.

The oxygen evolution process is a crucial part determining the total reaction kinetics of electrocatalytic overall water splitting for clean hydrogen production. However, for some semiconductor materials, e.g. tin dioxide (SnO2) and tungsten oxide (WO3), the water oxidation process generally proceeds following the two-electron pathway with rather high driving potential for the generation of hydrogen peroxide (H2O2 or HO2−). In this work, efficient electronic configuration modulation of SnO2 nanoparticles was realized by non-metallic phosphorus (P) doping, giving rise to the considerable transformation into a four-electron transfer-governed water oxidation reaction with the electrocatalytic activity even comparable to the benchmark RuO2 nanoparticles. These results validate the great potential in remarkably tuning the electrocatalytic performance of transition metal compound electrocatalysts with non-metallic element dopants.

The ultra-wideband near-infrared (NIR) emission of Bi-doped glass and fiber makes it play an increasingly important role in laser technology and optical communication system. However, challenge remains to grasp the original of NIR emission and manipulate the valence state of bismuth for efficient Bi-doped fiber lasers and amplifiers. In this article, we present a facile method to control the valence of bismuth by using one kind of porous host, the nano-porous silica glass (NPSG). Bi-doped silicate glass with novel NIR emission was obtained in NPSG based on glass phase separation technology (GPST). The valence state and NIR luminescence of bismuth can be controlled by sintering of NPSGs impregnated with Al 3 + and P 5 + ions in inert atmosphere. Three kinds of bismuth active centers (BACs) with their own fluorescence characteristics are formed in NPSG. Al can disperse bismuth active centers (BACs) to enhance O band NIR emission; P can promote the reduction of bismuth in glass to produce up-conversion and S+C+L+U band NIR emission. This work pushes us to take a big step towards understanding the truth of NIR emission of bismuth. The GPST may serve as key technology for efficient Bi-doped fiber lasers and amplifiers.

Metallic zinc (Zn) anode holds great promise for aqueous batteries but suffers from the dendrite growth and water-induced side reactions due to the absence of a stable solid electrolyte interphase (SEI) layer. Herein, we propose an efficient strategy to in-situ build a robust organic-inorganic hybrid SEI on Zn electrode (denoted as SEI-Zn) by electrochemically pre-cycling Zn electrodes in an organic electrolyte consisting of zinc trifluoromethanesulfonate salt and triethyl phosphate solvent. The as-formed SEI features an organic-rich outer layer and an inorganic Zn3(PO4)2-ZnF2-ZnS rich inner layer arising from the reductive decomposition of the organic electrolyte, which can isolate active Zn from the bulk electrolyte and allow a rapid and uniform Zn2+ diffusion. When the tailored SEI-Zn is applied into aqueous systems, the hydrogen evolution and Zn corrosion are significantly suppressed, whilst a dendrite-free Zn deposition with a preferred (002) orientation is characterized. The presence of SEI enables a prolonged lifespan of symmetric Zn//Zn cells over 2500 and 450 h at 1.0 and 10.0 mA cm−2, respectively, significantly outperforming the bare Zn counterpart. Moreover, both coin- and pouch- type SEI-Zn//V2O5·nH2O full batteries exhibit excellent cycling durability. This work will inspire the design of SEI on metal anodes for stable aqueous batteries.

Improving energy storage density and efficiency is the ultimate goal of dielectric materials used in ceramic capacitors. Among different dielectric materials, dielectrics in thin film state own superior energy performances due to less defects compared with ceramic. Herein, we report an optimized lead-free Zr-modified BiMg0.5Zr0.04Tix-0.04O3 composition with enhanced energy storage behavior via microstructural engineering. Rapid annealing can result in poorly crystallization in the film matrix confirmed by grazing incident X-ray diffraction GIXRD. The excess Ti source can effectively increase polarization and dielectric breakdown till to 97.0 μC/cm2 and 3403 kV/cm at x = 0.775, respectively. The optimized energy properties can be achieved at x = 0.775 with a high recoverable energy storage density Wreco of 87.8 J/cm3 and an efficiency η of 50%, indicative of excellent stability of storing electricity for the applications of pulse power electronics.

Grain refinement is significant for the mechanical properties of engineering alloys. We achieved a bi-ultrafine microstructure in an Mg–12Gd–3Y–0.5Zr alloy through equal channel angular pressing (E...

Nowadays, there is an urgent need for microwave absorbing materials with light weight, thin thickness, and strong absorbing ability to solve the problem of electromagnetic radiation. In this study, we report a novel high-performance aerogel absorber by growing MoO3-doped WO3 nanoflakes on reduced graphene oxide (rGO) sheets. The resultant rGO-Mo-WO3 aerogel displays a low density (∼75 mg/cm3) and unique hierarchical architectures including 3D porous microstructures, 2D rGO skeleton, and binary transition metal oxide of Mo-WO3 nanoflakes, thus leading to excellent microwave absorption performances. Typically, rGO-Mo-WO3 aerogel exhibits an ultra-strong reflection loss (RL) of −61.8 dB with a thin coating thickness of 1.54 mm. And a wide effective absorption bandwidth of 6.24 GHz can be achieved at a low filler loading of 8 wt%, much superior to previous ones. The synergistic effect of moderate polarization relaxation loss and weak conduction loss together with the porous microstructure for the aerogel result in the suitable impedance matching and strong microwave attenuation ability. This work may demonstrate a promising method to fabricate hierarchically nanostructured absorbers with the advantages of light weight, ultra-strong microwave absorption, and thin coating thickness.

Fluorescent solid-state carbon dots have drawn significant attention because of their intriguing optical properties, e.g., broad absorption, stable fluorescence, etc. However, obtaining the fluorescent solid-state carbon dots with a long-wavelength emission is still a challenging problem due to the notorious aggregation-induced quenching problem. In this paper, a technically feasible and low-cost approach for preparing fluorescent solid-state carbon dots is presented. The carbon dots are encapsulated in the nanoporous glass using the solution-phase-doping method. The size of nanoporous glass is tuned to 4.95 nm by regulating the ratio of boron to silicon to match the prepared CDs. Owing to the physical isolation and chemical connection of the -C-O-Si functional groups, the CDs are dispersed uniformly into the nanochannels of nanoporous glass. In this way, the aggregation-induced quenching problem of carbon dots is solved. The experiment results show that the photoluminescence has the excitation-independent emission at 609 nm, i.e., the prepared solid-state carbon dots are with orange fluorescence. More importantly, the solid-state carbon dots preserve orange fluorescence after heating treatment (400 °C) in the ambient atmosphere.

Sorbent morphology is significant to Hg0 removal performance due to its serious impacts on the number and availability of adsorption sites and the mass transfer of the Hg0 removal process. Given this, a novel sorbent was obtained by in-situ growth of Co3O4 nanoparticles on channel walls of wood vessel which has regular mesoporous channels. The effects of synthetic conditions of hydrothermal temperature and NH4F concentration on sorbent morphology and Hg0 removal performance are investigated. Characterization results show that Co3O4 nanoparticles integrate a monolithic shell as synthesis temperature rises, while the nanoparticles grow radially with the increase of NH4F concentration. Radial growth of nanoparticles results in a higher crystallinity. The sorbent synthesized at hydrothermal temperature of 90 °C with the NH4F concentration of 0.05 M (denoted as T90C0.05) has uniform Co3O4 nanoparticle size, homogeneous dispersion and a larger specific surface area. Furthermore, T90C0.05 has a higher chemisorbed oxygen concentration and a higher Co3+/Co2+, which is of benefit to Hg0 removal process. Therefore, T90C0.05 has an excellent Hg0 removal efficiency of 97% with a high gas hourly space velocity of 180, 000 h−1 at 200 °C and the Co3O4 loading is only wt.5%. The effects of compounded flue gas components on the Hg0 removal performance were also studied. NO can weaken the inhibition effect of NH3 through the reaction between NO and NH3 forming labile [NH2NO]. In contrast, SO2 can not weaken the inhibition effect of NH3 due to the production coming from the reaction of SO2 and NH3 is stable at Hg0 removal temperature.

The extended cycle life of cells is often sacrificed at the expense of high specific energy for high-nickel materials. Cation doping is a promising method to build high-nickel cathode with high energy density and long cycle life. Herein, a trace amount of Mg-B co-doping in LiNi0.6Mn0.2Co0.2O2 (NMC622) is investigated in this work, which shows improved structural and electrochemical stability of 1% Mg-0.5 % B co-doped material at both 30 and 55 °C in coin-cell. Comprehensive chemical composition, structural, and surface analysis are carried out in this paper. It was found that all the selected materials have a similar composition to the target. Moreover, Mg and B doping have different effects on the crystal structural change of NMC622, to be more specific, the c-lattice parameter increases with Mg doping, while the Li+/Ni2+ mixing content increases when B was incorporated into the lattice. Furthermore, the microstructure of primary particles was changed by B doping significantly as confirmed by the SEM images. There were marginal benefits in terms of structural and electrochemical stability of materials introduced by Mg or B sole doping. In comparison, incorporating a suitable amount of both Mg and B into NMC622, we found the capacity retention of cells was noticeably improved by reducing the impedance growth and preventing cation mixing during cycling. This study demonstrates the importance of co-incorporation of Mg, B, and optimizing the co-dopant content to stabilize NMC622 as cathode for lithium-ion batteries.

We have developed a facile strategy to fabricate model multicolor hydrogels via a straightforward mixing process of poly acrylonitrile-grafted methacrylamide (PANMAM), polymethacrylic acid (PMAA) and doped lanthanide (Eu/Tb) and zinc ions to form the interpenetrating dual-polymer gel networks. The hydrogels exhibit excellent tunability of multi-spectrum emission colors (including white light) by simply varying the stoichiometry of metal ions. Furthermore, taking the advantage of different metal ion response mechanisms, we have demonstrated the reversible acidity/alkalinity stimuli-responsive behaviors of white-light-emitting hydrogel (WLE gel). Meanwhile, the unique cross-linked network formed through hydrogen-bonding, metal-ligand coordination and ionic interaction is introduced to achieve favorable mechanical strength of hydrogels. These properties enable the possibility in obtaining fluorescent patterns on hydrogels, which are promising candidate for encrypted information with improved security.

Due to the temperature and volume changes caused by hydration heat, shrinkage, and creep, early-age concrete in steel-concrete composite girder bridges often have cracks even before the bridge opening to the traffic. In this study, thermo-mechanical behavior and concrete cracking risk in composite girders were investigated by field measurements and finite element models (FEM). Firstly, temperature field model and mechanical behavior model were established in sequence and verified by the measured data of temperature and strain. According to the FEM, the influence of interfacial stiffness on axial stress of the early-age concrete deck was studied, and proved to be nonnegligible. As for the steel girder, the influence of interfacial stiffness on the axial stress can be ignored except for the steel-concrete interfacial region near the end section of girders. Among temperature, shrinkage, and creep, temperature dominates the axial stress with the proportion of about 85% of the coupling axial stress (sum of the stress of temperature, shrinkage, and creep). The shrinkage effect causes tensile stress in concrete with a small proportion of about 3%. For creep effect, it causes opposite stress state in tension and compression with temperature in concrete deck. Finally, parametric studies involving initial temperature, curing temperature and the thickness of concrete deck were performed to evaluate the cracking risk of early-age concrete under different seasons. The result shows that, to avoid concrete cracking, concrete casting for a deck thinner than 0.2 m can be conducted without any curing method. While for the deck with a thickness from 0.2 m to 0.4 m, the concrete casting without any curing method should be conducted during specific period. For a deck thicker than 0.4 m, effective curing method must be used during concrete casting.

The double cladding Er/Yb/P co-doped fiber was fabricated by rod-in-tube method, in which the doped nanoporous silica glass (NPSG) was used as the core, the high-purity silica was used as the inner cladding. Under 980 nm laser excitation, the fiber has strong up-conversion luminescence, and its spectrum has luminescence peaks at 518 nm, 543 nm and 650 nm. The integrated intensity of the peak area at 518 nm, 543 nm and 650 nm has a strong linear relationship with the pump power in the double logarithmic coordinate system. By adjusting the fiber length and pump power, the relative luminescence intensity of 518 nm, 543 nm and 650 nm was changed, and different shapes of spectra were obtained. The mechanism of up-conversion luminescence tailoring with the fiber length and pump power has been investigated.

Metallic zinc (Zn) is an attractive anode material to use for building an aqueous battery but suffers from dendritic growth and water-induced corrosion. Herein, we report the use of vanillin as a bifunctional additive in aqueous electrolyte to stabilize the Zn electrochemistry. Computational, spectroscopic, and electrochemical studies suggest that vanillin molecules preferentially absorb in parallel on the Zn surface to homogenize the Zn2+ plating and favorably coordinate with Zn2+ to weaken the solvation interaction between H2O and Zn2+, resulting in a compact, dendrite-free Zn deposition and a stable electrode-electrolyte interface with suppressed hydrogen evolution and hydroxide sulfate formation. In the formulated 2 M ZnSO4 electrolyte with 5 mM vanillin, the Zn anode sustains high areal capacity (10 mAh cm-2 at 1 mA cm-2) and remarkable cycling stability (1 mAh cm-2 for 1000 h) in a Zn|Zn cell and high average Coulombic efficiency (99.8%) in a Zn|Cu cell, significantly outperforming the cells without vanillin. Furthermore, the vanillin additive supports stable operation of full Zn|V2O5 batteries and is readily generalized to a Zn(CF3SO3)2-based electrolyte. This work offers a facile and cost-effective strategy of electrolyte design to enable high-performance aqueous Zn batteries.

Although various cobalt-sulfide-based materials have been reported for the hydrogen evolution reaction, only a few have achieved high activity in both acid and alkaline electrolytes due to the inherent poor conductivity and low active sites. In this work, a heterojunction of cobalt sulfide and Mo2N is designed for efficient hydrogen evolution reactions in both acid and alkaline electrolytes. X-ray photoelectron spectroscopy reveals that Mo-S bonds are formed at the interface between Mo2N and CoS2, which result in the fabricated Mo2N/CoS2 materials exhibiting a considerably enhanced hydrogen evolution reaction activity than the corresponding Mo2N, CoS2, and most reported Mo- and Co-based catalysts in electrolytes of H2SO4 and KOH solutions. Density functional theory calculations suggest that the redistribution of charges occurs at the heterointerface. In addition, the interfacial active sites possess a considerably lower hydrogen adsorption Gibbs free energy than those atoms that are far away from the interface, which is beneficial to the process of hydrogen evolution reaction. This study provides a feasible strategy for designing hetero-based electrocatalysts with a tuned highly active interface.

PTFE/GF(glass fiber) composites are widely applied in high-frequency printed circuit board (PCB) substrate materials due to the excellent dielectric properties of PTFE and the low thermal expansion coefficient of GF. However, the poor interface compatibility between PTFE and GF affects the performance of the composite substrates. In this study, tetraethyl orthosilicate (TEOS) was used as the silicon source, and polydimethylsiloxane (PDMS) was the organic precursor to modify the surface of GF through the sol–gel method to promote the interface compatibility of GF and PTFE. The modified GF noted T-GF was filled in PTFE to prepare PTFE/T-GF composites. SEM, FTIR, XPS, and contact angle confirmed that organic–inorganic hybrids were successfully loaded on GF's surface. Moreover, compared with PTFE/GF and the conventional coupling agent modified GF filled PTFE composites, the PTFE/T-GF exhibited improved dielectric constant (2.305), decreased dielectric loss (9.08E−4), higher bending strength (21.45 MPa) and bending modulus (522 MPa), better thermal conductivity (0.268 W/m*K) and lower CTE (70 ppm/°C), making it has promising application as the substrate materials for high frequency PCB.

In this research, the characteristics of the bioactive glass (AG) and bio-inert carbon nanofibers (Cnano) in the bone formation was explored. The AG was prepared by sol–gel and combined with polyacrylonitrile (PAN) by electrospinning. Then, Cnano loaded with AG nanoparticles was prepared by carbonization. During the preparation process, the material supply ratio of the sol–gel precursor was changed to obtain 3 nanofiber scaffold materials (Canno/AG_01, Canno/AG_02, and Canno/AG_03). First, the release behavior of silicon ions, calcium ions, and phosphorus ions was investigated during the material preparation process, and Transwell was used for cabin culture, so that bone marrow mesenchymal stem cells (BMSCs) did not directly contact the materials. Besides, the expression levels of osteogenic differentiation genes in different culture sites were detected by reverse transcription-polymerase chain reaction (RT-PCR) method. There was an evaluation of the influences of increased AG content on trauma nursing and chondrocyte apoptosis in vitro. Finally, bone marrow blood mononuclear cells (BMWM) combined with Canno/AG materials were used for clinical research on skull repair. In the experiment, the ion dissolution levels of different prepared materials were different, but they had little effect on the proliferation of BMSCs. Canno/AG_02 with the highest level of silicon ion dissolution had good osteogenic differentiation ability, and RT-PCR proved that contact culture could markedly promote the proliferation and differentiation of BMSCs cells based on the prepared fiber morphology and cell contact effect. Moreover, Canno/AG_02 could be used as the wound dressing for skull fracture to achieve the nursing and rehabilitation effect of wound closure and promoting angiogenesis, and BMWM loaded with Canno/AG_02 could accelerate the tissue healing speed of patients with damaged skull defect.

Hydrogen peroxide (H2O2) has received increasing attention as an important green-oxidate and energy carrier, but the H2O2 production industry has been plagued by high energy consumption and high environment risk in current processing technology. Photocatalytic production of H2O2 from earth-abundant water and molecular oxygen (O2) is seemed to be a potential solution. Core–shell CdS@CdIn2S4 heterojunctions was prepared through a “sequential two-step hydrothermal growth” route. The photoexcited CdIn2S4 moiety transfers the conduction band electrons to CdS, leading to selective production of H2O2 via single-electron reduction of O2. In contrast, the valence band holes photoformed on the CdS moieties are transferred to CdIn2S4, leading to efficient oxidation of water. The electron–hole separation enhanced by the core–shell structure of CdS@CdIn2S4 heterojunctions and significantly suppresses the charge recombination, which resulting in greatly enhanced photocatalytic activity for H2O2 production. The resultant catalyst shows an ultra-high H2O2 production rate of 1408.4 μmol/L in non-sacrificial system, which is about 3.8 times higher than that of pure CdS. This inorganic photocatalysis therefore shows potential as an artificial photosynthesis for H2O2 production by powdered catalysts.

We report on a series of Er 3 + / Yb 3 + / P 5 + co-doped silica glass from nanoporous silica glass based on glass phase separation technology. The optical properties of the Er 3 + / Yb 3 + / P 5 + co-doped glasses were investigated. Measurements showed that phosphorus can promote energy transfer from Yb 3 + ions to Er 3 + ions while suppressing the energy transfer from Er 3 + ions to Yb 3 + ions and efficiently suppressing the amplified spontaneous emission (ASE) from Yb 3 + ions at 1030 nm. Additionally, the luminescence of Er 3 + ( I 4 13 / 2 → I 4 15 / 2 ) was greatly extended under 976 nm laser excitation, and the full width at half maximum (FWHM) of Er 3 + ( I 4 13 / 2 → I 4 15 / 2 ) was measured to be up to 72 nm and enables the luminescence peak redshifted. The emission cross section of Er 3 + ( I 4 13 / 2 → I 4 15 / 2 ) was calculated to be 1.6 * 10 − 20 cm 2 , one order higher than that of other silica glasses. It is suggested that the Er 3 + / Yb 3 + / P 5 + co-doped silica glasses based on nanoporous silica glass present great potential for broadband amplification.

Most of the current electrocatalysts for the methanol oxidation reaction are precious group metals such as Pt, Pd, and Ru. However, their use is limited due to their high cost, scarcity, and issues with carbon monoxide poisoning. We developed a simple method to prepare a nickel foam (NF)-based monolith electrode with a NiO nanosheet array structure as an efficient electrocatalyst toward the oxidation of methanol to produce formate. By a simple ultrasonic acid treatment and air oxidation at room temperature, an inert NF was converted to NiO/NF as a catalytically active electrode due to the uniform NiO nanosheet array that was rapidly formed on the surface of NiO/NF. In alkaline electrolytes containing methanol, the as-prepared NiO/NF catalysts exhibited a lower methanol oxidation reaction (MOR) potential of +1.53 V vs RHE at 100 mA cm-2 compared to that of inert NF samples. The difference in potentials between the EMOR and the EOER at that current density was found to be 280 mV, indicating that methanol oxidation occurred at lower potentials as compared to the oxygen evolution reaction (OER). We also observed that the NiO/NF could also efficiently catalyze the oxidation of CO without being poisoned by it. NiO/NF retained close to 100% of its initial activity after 20,000 s of methanol oxidation tests at high current densities above 200 mA cm-2. Because of the simple synthesis method and the enhanced catalytic performance and stability of NiO/NF, this allows methanol to be used as an OER masking agent for the energy-efficient generation of value-added products such as formic acid and hydrogen.

Metal–organic framework (MOF) is a promising electrochromic material due to its high specific surface area and tunable pore size, which can benefit the fast transportation of ion/charge. Here, a simple solvothermal deposition method for fabrication of Ni-MOF 74 electrochromic films on ITO is developed. It is found that the reaction temperature has played an important role in the morphology and electrochromic performance of as-prepared Ni-MOF 74 film. The film prepared at the optimized temperature exhibits the best electrochromic performance with a rapid switching speed (the coloration/bleaching time = 24.5/23.5 s). In addition, the optimized film displays a high optical contrast of 44.4% at 550 nm and can be stably switched for 650 cycles with

As a new class of crystalline porous organic materials, covalent organic frameworks (COFs) have attracted considerable attention in proton conduction due to their regular channels and tailored functionality. However, most COFs are insoluble and unprocessable, which makes the membrane preparation for practical usage a challenge. Herein, we employed surface-initiated condensation polymerization of trialdehyde and phenylenediamine in the synthesis of sulfonic COF (SCOF) coatings. The COF layer thickness can be finely tuned from ten to one hundred nanometers by controlling the polymerization time. Moreover, free-standing COF membranes were facilely obtained by sacrificing the bridging layer without any decomposition of the COF structure. Benefiting from the abundant sulfonic acid groups in the COF channels, the proton conductivity of SCOF membrane reached to 0.54 S cm -1 at 80 °C in pure water. To our knowledge, this is one of the highest values for pristine COF membrane in the absence of additional additives. Our approach would pave the way for the potential application of COF materials in proton conducting membranes.

Chiral gold nanoparticles (Au NPs) have attracted considerable attention in the fields of asymmetric catalysis, optical materials, and biosensing, owing to their chiroptical plasmonic properties. T...

Al-5Ti-B and Al-5Ti-B-Gd master alloy refiners were fabricated by fluorine salt casting method. The microstructure and phase constitution of the master alloys were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The results show that Al-Ti-B alloy refiner consists of Al3Ti phase and TiB2 phase. After Gd is introduced into the intermediate alloy, Ti2Al20Gd phase appears in the alloy, the size of Al3Ti is significantly reduced, and Ti-Al-Gd phase is found in the edge of Al3Ti phase. At the same time, some independent Ti-Al-Gd phases appear in local areas, which are Ti2Al20Gd phase determined by micro-area electron diffraction analysis. Analysis and calculation results of the high-resolution images of the Ti2Al20Gd/Al structure show that there is no other compound at the junction between the Ti2Al20Gd phase and Al, and Ti2Al20Gd phase has a great difference in atomic space with the α-Al, which cannot be directly used as heterogeneous nucleus. But, after being decomposed in the aluminum melt, the Ti2Al20Gd phase can promote the refinement effect of the refiner. In the Al-Ti-B-Gd master alloy, there are many dispersed Al3Ti particles with a size of less than 1 μm, which can promote the Al-5Ti-B refining effect.

Hierarchical nanoparticles are of great interest because they possess unique physicochemical properties and multiple functionalities, providing a wealth of possibilities for various applications. In this work, we have developed a well-designed method to prepare hierarchical magnetic nanoparticles Fe3O4@mSiO2@CS by integrating a solvothermal method for synthesizing the Fe3O4 core, a dualtemplating micelle system for preparing a layer of mesoporous silica (mSiO2) shell, and a silane coupling method via γ-glycidoxypropyltrimethoxysilane for binding a chitosan (CS) layer on the silica surface. The porous hierarchical nanoparticles were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), dynamic light scattering nanoparticle size analyzer, and specific surface area and pore size analyzer. The loading capacity and the release behavior of the as-prepared nanoparticles for doxorubicin hydrochloride were studied, and it was found that the drug release rate was faster at pH 6.0 than at pH 7.4, revealing the pH-responsive property of the nanoparticles.

The rational design of a hollow heterostructure promotes the development of highly durable anode materials for lithium-ion batteries. Herein, carbon-confined MoO2/Sn/NC@NC heterostructured nanotubes evolving from MoO3 nanorods have been successfully synthesized for the first time. In the growth of the Mo/Sn precursor, a peculiar microstructure evolution occurs from solid rods to hollow tubes through a solid-liquid reaction. The MoO2/Sn composite is restricted within the double carbon layer after subsequent annealing and carbonization that distinctly inherits the morphology of the Mo/Sn precursor. The resulting electrode shows good capacities with hardly any attenuation (925.4 mA h g-1 after 100 cycles at 100 mA g-1) and excellent long cycle life (620.1 mA h g-1 after 1000 cycles at 2 A g-1). The MoO2/Sn/NC@NC nanotubes contain the synergistic effect, elaborate core-shell structure, large specific surface areas, and abundant voids. These superiorities not only provide beneficial channels for the electrolyte to fully come into contact with electrode materials and more active sites for redox reactions but also effectively alleviate the volume fluctuation and sustain the electrical connectivity to retain a stable solid-electrolyte interface layer, indeed, bringing about the prominent Li-storage performance. The present study paves a feasible avenue to prepare core-shell structures with high reversible capacity and long-term cycle performance for energy storage devices.

Reducing the size of a catalyst to a single atom (SA) level can dramatically change its physicochemical properties and significantly boost its catalytic activity. However, the massive synthesis of SA catalysts still remains a grand challenge mainly because of the aggregation and nucleation of the generated atoms during the reaction. Here, we design and implement a spatially confined synthetic strategy based on a porous-hollow carbon nitride (p-CN) coordinated with 1-butyl-3-methylimidazole hexafluorophosphate, which can act as a nanoreactor and allow us to obtain metal SA catalysts (p-CN@M SAs). This relatively easy and highly effective method provides a way to massively synthesize single/multiple atoms (p-CN@M SAs, M = Pt, Pd, Cu, Fe, etc.). Moreover, the amorphous NiB-coated p-CN@Pt SAs can further increase the loading amount of Pt SAs to 3.7 wt %. The synthesized p-CN@Pt&NiB electrocatalyst exhibits an extraordinary hydrogen evolution reaction activity with the overpotential of 40.6 mV@10 mA/cm-2 and the Tofel slope of 29.26 mV/dec.

In this study, to evaluate the change in the stress and die-wall frictional characteristics during high-velocity compaction (HVC), a metal powder was subjected to HVC with a heavy hammer based on the stress-testing technology and Janssen-Walker model. The changes in the green density, stress characteristics and coefficients of friction at different impact heights were investigated. The density of green compacts increased with the increase in the impact height. The stress in the upper and lower punches and the die wall showed repeated loading and unloading. The coefficient of friction of the die wall underwent three stages and was related to powder densification. As the height position along the side wall was increased, the coefficient of friction increased gradually. With an increased impact height, the coefficient of friction increased significantly in the incomplete-molding stage but remained constant in the complete-molding stage. This work expands the theoretical basis of densification processing of a metal powder during HVC.

Dynamic compressive behavior of 2 kinds of Al/Teflon reactive materials samples are analyzed by using the Split Hopkinson pressure bar. The mass percentage of the samples is 26.5% Al and 73.5% Tefl...

Purpose This paper aims to improve the meshing effect of the gear teeth. It is recommended to analyze the deformation difference between the inner and outer surfaces of the flexspline. The purpose of this paper is to modify the profile of the flexspline based on the deformation difference to improve the transmission accuracy and operating life of the harmonic drive. Design/methodology/approach In this paper, ring theory is used to calculate the deformation difference of the inner and outer surfaces of the flexspline, and the actual tooth profile of the flexspline is corrected based on the deformation difference. Then, the flexspline is divided into multiple sections along the axial direction, so that the three-dimensional tooth profile of the flexspline is modified to improve the gear tooth meshing effect. Findings This paper proves the effect of the deformation difference between the inner and outer surfaces of the flexspline on the tooth backlash, which affects the transmission accuracy and life of the harmonic drive. It is recommended to modify the tooth profile of the flexspline based on the deformation difference, so as to ensure the tooth meshing effect. Originality/value This paper provides a new way for the optimization of the three-dimensional tooth profile design of the harmonic drive.

NASICON-type solid-state electrolyte has been reported to improve the structural and electrochemical stability of high nickel positive electrode materials; however, the impact of NASICON-type solid-state electrolyte on the performance of lithium-rich cathode has been barely studied. In this work, various contents of LiTi2(PO4)3 (LTP)-coated Li1.2Ni0.13Mn0.54Co0.13O2 have been made via a wet chemical method followed by sintering at 550 °C for 3 h. Those modified materials failed to show improvement in electrochemical properties including specific capacity, coulombic efficiency (CE), rate capability, and cycle life compared with uncoated material. Thick LTP coating even decreases the average discharge voltage and increases the impedance and voltage hysteresis of cells. XRD, TEM, and SAED images revealed non-uniform coating with multiple components including LiTi2(PO4)3, TiP2O7, and TiO2. This work suggests LTP coating on Li1.2Ni0.13Mn0.54Co0.13O2 using a wet chemical method might be challenging and need to be carefully carried out.

Wood vessel in natural wood (NW) as the channel for water and inorganic salt transport has a natural aligned microchannel structure and a great hydrophily. In the present work, NW was used as catalyst support which was directly impregnated in Co(NO3)2 solution and then calcined in N2 atmosphere to prepare a catalyst (denoted as Co/NWBC-OS), which was called a one-step calcination method. For comparison, NW biochar (NWBC) derived from pyrolytic NW was also impregnated in Co(NO3)2 solution and calcined in N2 atmosphere to prepare catalyst (denoted as Co/NWBC-TS), which was called a two-step calcination method. Characterization results reveal that NW possesses a greater hydrophily and wettability than NWBC, which is beneficial to impregnation process resulting in a better active components dispersion. In the meanwhile, Co/NWBC-OS has a higher Co3+/Co2+ ratio and more surface chemisorbed oxygen. The higher Co3+/Co2+ ratio can generate more oxygen vacancies which can capture and activate gaseous oxygen to form more surface chemisorbed oxygen. Surface chemisorbed oxygen as the main active site can greatly promote Hg0 removal performance. These results lead to an excellent Hg0 removal efficiency of Co/NWBC-OS which is 99% at 180 °C. Additionally, O2 and NO can promote the Hg0 removal process whereas H2O, SO2 and NH3 exert an obviously prohibited effect on Hg0 removal performance.

Cypate is an organic material with tumor treatment function, which has photothermal effect. Based on the characteristics of this material, this study adopted the coupling method to obtain FB-Cypate nano-microspheres, BDI-1-FB-Cypate albumin nano-microsphere diad and CPPs-BDI-1-FB-Cypate albumin nano-microsphere triad. Cypate and FB-Cypate materials were characterized by scanning TEM, particle size analyzer, and spectrophotometer. An injection-ureter introduction device was used to perfuse pediatric bladder cancer cells into the bladder cavity of nude mice, and different Cypate-type material solutions were perfused into the bladder cavity at the same time. Then, the anti-bladdertumor performance of different materials on tumor cells was compared. The test proves that the average particle diameter of FB-Cypate material is (102.3 ±8.6) nm, which can be used for near-infrared imaging, and the temperature rise is obvious under light conditions. In the test of inhibiting bladder cancer cells in children, the use of Cypate type materials can significantly inhibit the survival of bladder tumor cells, and it has less negative impact on physiological functions after surgery.

Effects of the staggered blades on unsteady pressure pulsations of a centrifugal pump with a specific speed ns=147 are investigated by the numerical simulation method. The obtained results are compared with the original blades. To clarify the resulting effects, eight monitoring points are used to extract pressure signals at three typical working conditions, and component at the blade passing frequency fBPF is emphasized. Results show that the pump efficiency and head will be reduced by the staggered blades, and at the nominal flow rate, the reduction is about 1.5% from comparison with the original blades. For all the eight points, the staggered blades contribute to the reduction of pressure amplitudes at fBPF when the pump works at three flow rates. The averaged reduction is 15.5% at the nominal flow rate. However, the negative effect on the second harmonic of fBPF will be caused by the staggered blades, and the corresponding pressure amplitude will increase at 2fBPF. It means that the pressure pulsation energy will be redistributed among the discrete components in pressure spectrum by the staggered blades. From the TKE distribution, it is found that the TKE values on the blade pressure side will be significantly affected by the staggered blades.