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A MOF-derived Cu2S@NSC hybrid in which ultrathin Cu2S nanoparticles are encapsulated in a N,S co-doped carbon matrix was developed, which possesses excellent electrochemical properties serving as a lithium-ion battery anode.

Objective Calcified aortic valvular disease is known as an inflammation-related process related to force. The purpose of this study was to determine whether micromechanical force could induce valve calcification of porcine valvular interstitial cells and to examine the role of integrin αvβ3 in valvular calcification by using a novel method: magnetic twisting cytometry. Methods Porcine valvular interstitial cells were cultured in vitro, and micromechanical force was applied to porcine valvular interstitial cells using magnetic twisting cytometry. Changes in calcification-related factors osteopontin and RUNX2 were detected. By using the calcification medium, the optimal magnetic twisting cytometry parameters for inducing valvular interstitial cell calcification were determined, and a magnetic twisting cytometry calcification promotion model was established. The role of αvβ3 in calcification was studied by using αvβ3 antagonists to block the function of αvβ3. Results Reverse transcription polymerase chain reaction assays showed that the expression of osteopontin was enhanced 30 minutes after 25G-1Hz 5 minutes of stimulation. Western blotting assays showed that the expression of osteopontin and RUNX2 was upregulated 24 hours after 25G-1Hz 5 minutes of stimulation. The optimal magnetic twisting cytometry parameter for inducing porcine valvular interstitial cell calcification was 25G-2Hz for 10 minutes. The expression of osteopontin and RUNX2 decreased significantly after the addition of αvβ3 antagonist. Clinically, patients with bicuspid aortic valves had high expression of RUNX2 and β3 in the aortic valve, and β3 significantly correlated with RUNX2. Conclusions By using magnetic twisting cytometry, we established a porcine valvular interstitial cell calcification model by micromechanical force stimulation and obtained the optimal parameters. Integrin αvβ3 plays a key role in the aortic valve calcification process.

Benefitting from the abundance and inexpensive nature of potassium resources, potassium-ion energy storage technology is considered a potential alternative to current lithium-ion systems. Potassium-ion capacitors (PICs) as a burgeoning K-ion electrochemical energy storage device, are capable of delivering high energy at high power without sacrificing lifespan. However, owing to the sluggish kinetics and significant volume change induced by the large K

The large volume expansion and poor electrical conductivity of copper phosphide (Cu3P) during the cycle limit their further application as anode of lithium-ion batteries. Therefore, polyvinylpyrrolidone (PVP) modified Cu3(BTC)2-derived (BTC = 1, 3, 5-Benzentricarboxylic acid) in-situ N/P-co-doped Octahedron carbon encapsulated Cu3P nanoparticles (Cu3P@NPC) are successfully prepared through a two-step process of carbonization and phosphating. The N/P-co-doped Octahedron carbon matrix improves the conductivity of Cu3P and moderates the volume expansion during the lithiation/delithiation process. Meanwhile, the interaction between the Cu3P and the doped carbon matrix is methodically explored by using density functional theory (DFT). Through the analysis of the partial charge density, the density of states and the Bader charge, and the calculation results verify the correctness of the experimental observation results, that is, Cu3P@NPC has good electrochemical performance. The results show that Cu3P@NPC, as the anode of Lithium-ion batteries, has excellent electrochemical performance: it exhibits satisfactory rate performance (251.9 mAh g−1 at 5.0 A g−1) and excellent cycle performance (336.4 mAh g−1 at 1 A g−1 over 1000 cycles). This article provides an effective strategy for the encapsulation of metal phosphide nanoparticles in a doped carbon matrix.

Bimetal oxides have attracted much attention due to their unique characteristics caused by the synergistic effect of bimetallic elements, such as adjustable operating voltage and improved electronic conductivity. Here, a novel bimetal oxide Sn0.918Sb0.109O2@graphene (TAO@G) was synthesized via hydrothermal method, and applied as anode material for lithium ion batteries. Compared with SnO2, the addition of Sb to form a bimetallic oxide Sn0.918Sb0.109O2 can shorten the band gap width, which is proved by DFT calculation. The narrower band gap width can speed up the lithium ions transport and improve the electrochemical performances of TAO@G. TAO@G is a structure in which graphene supports nano-sized TAO particles, and it is conducive to the electrons transport and can improve its electrochemical performances. TAO@G achieved a high initial reversible discharge specific capacity of 1176.3 mA h g−1 at 0.1 A g−1 and a good capacity of 648.1 mA h g−1 at 0.5 A g−1 after 365 cycles. Results confirm that TAO@G is a novel prospective anode material for LIBs.

Stiffness and forces are two fundamental quantities essential to living cells and tissues. However, it has been a challenge to quantify both 3D traction forces and stiffness (or modulus) using the same probe in vivo. Here, we describe an approach that overcomes this challenge by creating a magnetic microrobot probe with controllable functionality. Biocompatible ferromagnetic cobalt-platinum microcrosses were fabricated, and each microcross (about 30 micrometers) was trapped inside an arginine–glycine–aspartic acid–conjugated stiff poly(ethylene glycol) (PEG) round microgel (about 50 micrometers) using a microfluidic device. The stiff magnetic microrobot was seeded inside a cell colony and acted as a stiffness probe by rigidly rotating in response to an oscillatory magnetic field. Then, brief episodes of ultraviolet light exposure were applied to dynamically photodegrade and soften the fluorescent nanoparticle–embedded PEG microgel, whose deformation and 3D traction forces were quantified. Using the microrobot probe, we show that malignant tumor–repopulating cell colonies altered their modulus but not traction forces in response to different 3D substrate elasticities. Stiffness and 3D traction forces were measured, and both normal and shear traction force oscillations were observed in zebrafish embryos from blastula to gastrula. Mouse embryos generated larger tensile and compressive traction force oscillations than shear traction force oscillations during blastocyst. The microrobot probe with controllable functionality via magnetic fields could potentially be useful for studying the mechanoregulation of cells, tissues, and embryos.

High-entropy oxide (HEO) is an emerging type of anode material for lithium-ion batteries with excellent properties, where high-concentration oxygen vacancies can effectively enhance the diffusion coefficient of lithium ions. In this study, Ni-free spinel-type HEOs ((FeCoCrMnZn)

High entropy oxides (HEOs) have attracted the attention of researchers due to their high theoretical specific capacity and structural stability. However, the effect of elements in HEOs on material properties is unknown. In this work, HEOs (FeNiCrMnZn)3O4 and (FeNiCrMnMg)3O4 were successfully synthesized and used as anode materials for lithium ion batteries. The effects of Zn and Mg on the properties of HEOs were studied from the aspects of crystal structure, micro morphology, and surface valence. Results show that Zn enhances the lithium storage performance of HEOs theoretically, which is verified in the later electrochemical performance tests. (FeNiCrMnZn)3O4 is better than (FeNiCrMnMg)3O4 in all aspects of rate properties, cycle performance, and electrochemical impedance spectroscopy. Therefore, the introduction of electrochemically active metals, such as Zn, can improve the performance of HEOs, thereby providing ideas for the subsequent design and application of HEOs.

Growing electroactive materials directly on a three-dimensional conductive substrate can effectively reduce the “ineffective area” of the electrode during the electrochemical reaction, increase the utilization rate of the material, and thus increase the energy density of the device. Using the network structure of the three-dimensional conductive substrate to design electrode materials with unique microstructures can also improve the stability of the materials. In this work, we obtained different copper-based materials on the copper foam (CF) by in-situ growth method, and designed an independent three-dimensional layered CuO@NiCoFe-S (CuO@NCFS) core–shell nanostructure composite material. CuO@NCFS exhibits excellent electrochemical performance, reaching a specific capacitance of 4551 mF cm−2 at a current density of 1 mA cm−2 with good cycle stability (94.2% after 5000 cycles). In addition, the asymmetric supercapacitor (ASC) uses CuO@NCFS as the positive electrode and rGO as the negative electrode, which can provide an energy rate density of 4.5 mW cm−2 at a high energy density of 99.9 μWh cm−2. The findings provide some insight into rational design of electrode materials for high performance energy storage.

Pathogens transmitted through the water environment pose a great threat to human health. Hence developing more reliable and efficient antibacterial materials to eliminate bacterium in water environments is urgent. Herein, we posed a novel strategy of interweaving carboxymethyl chitosan (CMCS) and Ag/Cu-MOFs to construct renewable Ag/Cu-BTC@CMCS composite beads with rapid sterilization, long-term antibacterial effects and high biosafety. Characterizations revealed that CMCS and bimetallic MOFs act as the "warehouses" of metal ions and played key roles in anchoring, storage, delivery, and controlled release of metal ions. The synergistic antibacterial effect achieved by the combination of Ag

The lack of antimicrobial effect of commercial paper coating for food packaging makes it difficult to prevent food spoilage and harms the environment by non-biodegradation. Herein, carboxymethyl cellulose (CMC) provides negatively charged sites for anchoring Ag

Design and fabrication of novel electrode materials with excellent specific capacitance and cycle stability are urgent for advanced energy storage devices, and the combinability of multiple modification methods is still insufficient. Herein, Ni2+, Zn2+ double-cation-substitution Co carbonate hydroxide (NiZnCo-CH) nanosheets arrays were established on 3D copper with controllable morphology (3DCu@NiZnCo-CH). The self-standing scalable dendritic copper offers a large surface area and promotes fast electron transport. The 3DCu@NiZnCo-CH electrode shows a markedly improved electrochemical performance with a high specific capacity of ∼1008 C g-1 at 1 A g-1 (3.2, 2.83, and 1.26 times larger than Co-CH, ZnCo-CH, and NiCo-CH, respectively) and outstanding rate capability (828.8 C g-1 at 20 A g-1) due to its compositional and structural advantages. Density functional theory (DFT) calculation results illustrate that cation doping adjusts the adsorption process and optimizes the charge transfer kinetics. Moreover, an aqueous hybrid supercapacitor based on 3DCu@NiZnCo-CH and rGO demonstrates a high energy density of 42.29 Wh kg-1 at a power density of 376.37 W kg-1, along with superior cycling performance (retained 86.7% of the initial specific capacitance after 10,000 cycles). Impressively, these optimized 3DCu@NiZnCo-CH//rGO devices with ionic liquid can be operated stably in a large potential range of 4 V with greatly enhanced energy density and power capability (110.12 Wh kg-1 at a power density of 71.69 W kg-1). These findings may shed some light on the rational design of transition-metal compounds with tunable architectures by multiple modification methods for efficient energy storage.

Overuse of pesticides is an urgent issue to be solved in sustainable agriculture. Based on the synergistic drug loading effect of β-cyclodextrin (β-CD) encapsulation and alginate (Alg) cross-linking, a new environment-responsive drug delivery system (TMX-loaded Alg/β-CD) was constructed. The relationship between carrier structure and solubility of thiamethoxam (TMX) was researched by molecular simulation. β-CD has good binding affinity with TMX, which can increase TMX solubility by 40 %. Further co-loading with alginate could double the drug loading of the cyclodextrin inclusion complex up to 41 %. TMX-loaded Alg/β-CD exhibits excellent environment-responsive controlled-release performance, and TMX sustained release time is 7.5 times longer than that of commercial agents. The pest control efficacy of TMX-loaded Alg/β-CD is 20 days longer than that of commercial TMX, and the crops has no pesticide residues after using. This study provides a promising strategy for the commercial application of polysaccharide in pest control and pesticide reduction.

Various solid state phase transformations exist in metastable β-type Ti alloys, which can be employed to optimize the mechanical properties. In this paper, synchrotron X-ray diffraction (SXRD) experiments were carried out to study the phase transformations of a Ti36Nb5Zr alloy subjected to different thermomechanical treatments. Furthermore, the correlation between the phase constitutions and the mechanical properties was discussed. The α″ texture formed, and high-density defects were introduced after cold rolling of the solution treated specimen, leading to the decrease in Young’s modulus and the increase in strength. The cold-rolled specimens were then annealed at temperatures from 423 to 773 K for 30 min. Both the Young’s modulus and strength increased with annealing temperatures increasing up to 673 K, which resulted from the precipitation of the ω and/or α phases. With further increase in annealing temperatures to 773 K, the β → α precipitation replaced the β → ωiso phase transformation, and the density of defects decreased, leading to the decrease in both the Young’s modulus and strength. These results provide theoretical basis for the design biomedical Ti alloys with both low Young’s modulus and high strength. 亚稳β钛合金中存在多种可以用来优化材料力学性能的固态相变。本文利用同步辐射X射线衍射 (SXRD) 实验 研究了Ti36Nb5Zr合金在热机械处理过程中的相变行为, 并讨论了相组成与力学行为的相关性。固溶态合金经冷轧处理后引入高密度缺陷并形成α″织构, 这导致杨氏模量下降和强度上升。冷轧态合金随后在423 到773 K退火30 min。当退火温度升至673 K时, 杨氏模量和强度都升高, 这可以归因于ω相和α相的析出。当退火温度进一步升高至773 K时, β→α析出相变取代β→ωiso相变, 并且位错密度下降, 导致杨氏模量和强度同时下降。本文的结果为新型低模量高强度生物医用钛合金的设计提供了理论基础。

The phase transformations during thermomechanical processing can be employed to optimize mechanical properties of β-type Ti alloys. However, such understandings are still lacking for the alloy consisting of dual β + α″ phases in solution-treated and quenched state. In this paper, the phase transformations in a Ti38Nb model alloy subjected to different thermomechanical processing were investigated by using synchrotron X-ray diffraction (SXRD) experiments, and their influence on the Young’s modulus was discussed. The results indicated that high-density dislocations introduced by cold rolling still existed after annealing at temperatures lower than 573 K, which can decrease the martensitic transformation start temperature to below room temperature. With annealing temperatures increasing, the α″ → β, β → ωiso, and β → α phase transformations occurred successively. At annealing temperature of 473 K, the specimen consisted of a trace of α″ and ω phases as well as dominant β phase which was kept to room temperature by the high density of dislocations, rather than by the chemical stabilization. As a result, an ultralow Young’s modulus of 25.9 GPa was realized. Our investigation not only provides in-depth understandings of the phase transformations during thermomechanical processing of β-type Ti alloys, but also sheds light on designing biomedical Ti alloys with ultralow Young’s modulus. β钛合金在热机械处理过程中的相变可以用来优化其机械性能。然而对于固溶态为β + α″的双相合金, 其相变和性能关系的研究尚且缺乏。本文利用同步辐射X射线技术研究了Ti38Nb合金在不同热机械处理状态下的相组成, 并讨论了其对杨氏模量的影响规律。结果表明冷轧引入的高密度位错在低于573 K退火后仍然存在, 这可以将马氏体相变点降至室温以下。随退火温度的升高, α″ → β, β → ωiso和β → α相变依次发生。当退火温度为473 K时, 样品中主要由β相组成并含有少量α″和ω相。这其中β相是通过高密度位错保留至室温而非化学成分稳定化。因此合金可以实现25.9 GPa的超低杨氏模量。本研究不但对β钛合金在热机械处理过程中的相变行为提供了深入理解, 而且为超低杨氏模量生物医用钛合金的开发提供了新思路.

The simultaneous strengthening of mechanical and magnetic properties is an ideal fabrication strategy for soft-magnetic materials. A non-equiatomic Al19Co20Fe20Ni41 eutectic high-entropy alloy was prepared to investigate the alloying effect of B on the microstructure evolution, phase formation, mechanical and soft-magnetic properties. With the increase in B content, the microstructures of (Al19Co20Fe20Ni41)100−xBx alloys transformed from the initial lamellar eutectic structure (x=0) to the divorced eutectic structure (x>0.6). Fine borides precipitated in the intergranular phase (x≥0.6). The hardness of alloys increased from HV 328.66 to HV 436.34 and the compression mechanical performance displayed a transition from plastic material to brittle material. The Al19Co20Fe20Ni41 alloy possesses good soft-magnetic properties, and the minor B addition has little effect on it. Increasing the resistivity can effectively reduce the eddy current loss when used as a soft-magnetic material.

Transition metal hydroxides with three-dimensional heterostructure have been proved to be promising candidates as the electrode materials for energy storage. Herein, a layered C@MnNiCo–OH/Ni3S2 core-shell heterostructure, composed of grass-like Ni3S2 nanosheets, interlaced ultrathin MnNiCo–OH nanosheets and the coated amorphous carbon, has been successfully designed and synthesized by the facile hydrothermal and electrodeposition processes, which exhibits superior electrochemical performance. The unique core-shell structure is conductive to enlarge the active sites and provide charge transfer rate and redox reactions. The specific capacitance of the C@MnNiCo–OH/Ni3S2/NF electrode could reach 2332 mF cm−2 at 1 mA cm−2 and reserves 89.45 % capacitance after 5000 continuous cycles. Besides, the two-electrode device assembled by C@MnNiCo–OH/Ni3S2/NF and activated carbon (C@MnNiCo–OH/Ni3S2/NF//AC) shows an excellent density of 73.84 Wh kg−1 at 800 W kg−1. The remarkable performances make it possible for the C@MnNiCo–OH/Ni3S2/NF nanocomposite to apply in the area of conversion and energy storage.

In this work, using foamed nickel as a nickel source, a self-supporting in situ growth binder-free Ni3S2/FL-Ti3C2/Ni electrode with a 2D heterojunction structure was synthesized via a one-step hydrothermal method after etching a few-layer Ti3C2(FL-Ti3C2) MXene. This electrode provides a high specific capacitance of 1752 mF/cm2 in a 3 M KOH electrolyte at 1 mA/cm2 and has excellent rate performance (75.5% at 10 mA/cm2) and electrochemical stability (74.79% after 5000 cycles). An asymmetric supercapacitor is prepared with Ni3S2/Ti3C2/Ni as the positive electrode and AC as the negative electrode. The maximum energy density and the power density are 32.7 μWh/cm2 and 8.0211 mW/cm2, respectively.

Chemical dealloying is an emerging strategy that can be applied to synthesize porous materials. The structure morphologies of the active materials were precisely regulated by designing the various NaOH corrosion solutions. Three-dimensional micro–nanorods-like structure Ni75Cu25O bimetallic oxide with ultra-high electrochemical properties have been obtained, which used Al65Cu15Ni20 precursors through a dealumination strategy. Meanwhile, three-dimensional micro–nanorods-like structure Ni75Cu25O demonstrates an unusual extraordinary specific capacitance (16.96 F cm−2 at 10 mV s−1) and excellent cycling stability (100.8% retention after 5000 cycles at 10 mV s−1). Here, the transition bimetallic oxides by using the dealloying strategy can be applied to develop novel guidances and ideas for the generation of energy storage devices.