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Polyoxometalates (POMs)-based materials, with high theoretical capacities and abundant reversible multi-electron redox properties, are considered as promising candidates in lithium-ion storage. However, the poor electronic conductivity, low specific surface area and high solubility in the electrolyte limited their practical applications. Herein, a double-shelled hollow PMo12 -SiO2 @N-C nanofiber (PMo12 -SiO2 @N-C, where PMo12 is [PMo12 O40 ]3- , N-C is nitrogen-doped carbon) was fabricated for the first time by combining coaxial electrospinning technique, thermal treatment and electrostatic adsorption. As an anode material for LIBs, the PMo12 -SiO2 @N-C delivered an excellent specific capacity of 1641 mA h g-1 after 1000 cycles under 2 A g-1 . The excellent electrochemical performance benefited from the unique double-shelled hollow structure of the material, in which the outermost N-C shell cannot only hinder the agglomeration of PMo12 , but also improve its electronic conductivity. The SiO2 inner shell can efficiently avoid the loss of active components. The hollow structure can buffer the volume expansion and accelerate Li+ diffusion during lithiation/delithiation process. Moreover, PMo12 can greatly reduce charge-resistance and facilitate electron transfer of the entire composites, as evidenced by the EIS kinetics study and lithium-ion diffusion analysis. This work paves the way for the fabrication of novel POM-based LIBs anode materials with excellent lithium storage performance.

Perpetual pavement has become an important research area of highway development in China. Ensuring the durability of materials is an essential measure to achieve the goal of perpetual pavement cons...

The host-guest interaction can remarkably alter the physiochemical properties of composite materials. It is crucial to clarify the mechanism by revealing the influence of the host on the electronic structure of the guest molecules. Herein, we study the structural variation of polyoxometalates (POMs) after being confined in single-walled carbon nanotubes (SWNT). What we found is that in addition to the reported charge transfer from SWNT to POM, an intramolecular electron transfer within a single POM cluster can be observed in the POM@SWNT composites. Moreover, the charge density on the bridged oxygen of POMs is prominently enhanced. The structural change and electron reconfiguration of POMs upon encapsulation in SWNT significantly speed up electron and ion transport, leading to the improved electrochemical performance for sodium ions storage.

Polyoxometalates (POMs) have shown great potential in sodium-ion batteries (SIBs) due to their reversible multielectron redox property and high ionic conductivity. Currently, POM-based SIBs suffer from the irreversible trapping and sluggish transmission kinetics of Na

Chemo/chemodynamic synergistic therapy is a promising strategy to improve the antitumor effect. However, hypoxia and a limited amount of hydrogen peroxide (H2O2) in the tumor microenvironment (TME) severely restrict the therapeutic efficacy of this combined treatment. Herein, we report biodegradable doxorubicin (Dox)-loaded copper–metformin (Met) nanoscale coordination polymers (Dox@Cu–Met NPs), which exert a chemo/chemodynamic synergistic therapeutic effect by reducing oxygen (O2) consumption to promote H2O2 accumulation in the tumor. Inside tumor cells, Met can inhibit the consumption of O2 to relieve tumor hypoxia by suppressing mitochondrial respiration. The alleviated-tumor hypoxia can not only elevate H2O2 content via the Dox-activated cascade reaction of nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (NOXs) and superoxide dismutase (SOD), but also improve the efficacy of Dox. More importantly, the depletion of glutathione (GSH) accompanies the whole treatment process, which can realize the conversion of Cu2+ to Cu+ and boost reactive oxygen species (ROS) accumulation to improve chemodynamic therapy (CDT) efficacy. Meanwhile, Met is expected to cut off the energy supply by inhibiting respiration, leading to starvation therapy. In vivo investigations demonstrate that tumor growth is significantly inhibited through the enhanced chemo/chemodynamic synergistic treatment. This work provides a new paradigm for cancer therapy using an economical and straightforward method to construct a synergistic nanomedicine platform.

Large scale synthesis of high-efficiency bifunctional electrocatalyst based on cost-effective and earth-abundant transition metal for overall water splitting in the alkaline environment is indispensable for renewable energy conversion. In this regard, meticulous design of active sites and probing their catalytic mechanism on both cathode and anode with different reaction environment at molecular-scale are vitally necessary. Herein, a coordination environment inheriting strategy is presented for designing low-coordination Ni2+ octahedra (L-Ni-8) atomic interface at a high concentration (4.6 at.%). Advanced spectroscopic techniques and theoretical calculations reveal that the self-matching electron delocalization and localization state at L-Ni-8 atomic interface enable an ideal reaction environment at both cathode and anode. To improve the efficiency of using the self-modification reaction environment at L-Ni-8, all of the structural features, including high atom economy, mass transfer, and electron transfer, are integrated together from atomic-scale to macro-scale. At high current density of 500 mA/cm2, the samples synthesized at gram-scale can deliver low hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) overpotentials of 262 and 348 mV, respectively.

Tin sulfide (SnS) is an attractive anode material for energy storage, but suffers from poor reversibility and serious polarization. In this work, to increase electron and ion transportation and the structural stability of SnS, polypyrrole–phosphomolybdic acid-coated SnO2@C spheres were used as self-templates to construct SnS@C nanospheres coated with MoS2 nanosheets and a nitrogen, phosphorus-codoped carbon layer (SnS@C/MoS2@N,P-C). Endowed with a synergetic effect from SnS, MoS2, and the carbon network, SnS@C/MoS2@N,P-C delivered a first reversible capacity of 628 mA h g−1 with a high initial coulombic efficiency of 74.9%, capacity retention of 59.8% over 2000 cycles at 5.0 A g−1 and an exceptional rate capability of 250 mA h g−1 at 10.0 A g−1 when used as an anode material for sodium-ion batteries (SIBs). This high rate capability is possibly promoted by pseudocapacitive behavior attributed to the rich interfaces between the different components. Moreover, an assembled full cell with Na3V2(PO4)3@C as the cathode exhibits a capacity of 455 mA h g−1 at 0.5 A g−1 after 50 cycles, showing good potential for practical applications in the future.

Perpetual pavement has become an important research field of highway development in China. Reasonable selection of pavement structure and ensuring the durability of the structure are one of the necessary measures to build perpetual pavements. The inverted asphalt pavement structure can not only provide high strength and good bearing capacity of semi-rigid base, but also make use of the graded crushed stones for restraining the reflection cracks of semi-rigid base. This paper presented a study on three pavement structures are, namely, a semi-rigid asphalt pavement and two inverted asphalt pavements. The performances of the three pavement structures after one million loading repetition are obtained. Taking rutting depth, deflection and dynamic response as evaluation indexes, the feasibility of inverted asphalt pavement structure as perpetual pavement structure is evaluated. It is found that the composite asphalt pavement structure with permeable asphalt mixture of large particle size as base and cement stabilized macadam as subbase has the best performance as perpetual pavement.

High-viscosity modified asphalt (T-HVA) specifically used for drainage/permeable asphalt pavement was prepared by composite modification of matrix asphalt using a thermoplastic elastomer (TPE) and SBS particles. The performance of the high-viscosity modified asphalt (T-HVA) was characterized by conventional tests, and compared with the performance of 70# asphalt, SBS modified asphalt and engineering high-viscosity asphalt. The results show that all the indicators of the modified asphalt are better than that of the matrix asphalt, and the dynamic viscosity of the T-HVA is greater than one million Pa.s, which is much higher than that of the engineering high-viscosity asphalt and SBS modified asphalt. The segregation test shows that the compatibility and stability of T-HVA asphalt are better than others. Cohesion test shows that the cohesion of the modified asphalt is obviously better than that of the matrix asphalt at different temperatures, and the higher the temperature, the better the cohesion, and the cohesion of the T-HVA before and after aging is relatively stable. The result of the peeling rate measured by ultraviolet spectrophotometry shows that: the peeling rate of the T-HVA is the smallest, i.e., the adhesion is the best, and is consistent with the dynamic viscosity, i.e., the greater the dynamic viscosity, the better the adhesion. Based on the comprehensive analysis of various indicators. The results of Performance Grade (PG) grading test show that T-HVA has good high and low temperature performance. The modified materials with good dispersion in asphalt and the TPE particles as high elastic interlocking units are uniformly distributed in the network structure; The T-HVA has relatively strong aggregate adhesion and cohesiveness, exhibits good high temperature stability and low temperature flexibility, and is suitable for drainage/permeable asphalt pavement. Keywords: Pavement engineering, High-viscosity modified asphalt, Cohesion and adhesion, Permeable asphalt pavement

Polyoxometalate (POM)-based materials are considered as promising candidates for lithium-ion batteries (LIBs) due to their stable and well-defined molecular structure and reversible multielectron redox properties. Currently, POM-based electrode materials suffer from high interfacial resistance and low uniformity. Herein, we reported a self-supported POM-based anode material for LIBs by electrodepositing H

Polyoxometalates (POMs)-based materials, with high theoretical capacities and abundant reversible multi-electron redox properties, are considered as promising candidates in lithium-ion storage. However, the poor electronic conductivity, low specific surface area and high solubility in the electrolyte limited their practical applications. Herein, a double-shelled hollow PMo

How to in situ detect intracellular telomerase activity with high sensitivity still faces many challenges. This paper constructs a new fluorescence biosensing platform for the sensitive detection of intracellular telomerase activity via the combination of nanoflare and hybridization chain reaction (HCR)-based signal amplification on a single patchy gold/carbon nanosphere (PG/CNS), which has two or more distinct parts and allows hybridized-DNA (HS-DNA/Primer-DNA/Flare-DNA) and H1/H2-DNA (a pair of cross complementary DNA hairpins) to bind onto their surfaces via Au–S bond and electrostatic interaction, respectively. In the presence of telomerase, Primer-DNA (telomerase primer) extends at its 3′ end to produce a telomeric repeated sequence, resulting in the release of Flare-DNA followed by the recovery of the fluorescence. Subsequently, the released Flare-DNA further initiates cross hybridization of H1 and H2 DNA from mimic-HCR system to amplify the fluorescence signal. The in vivo confocal microscopy studies demonstrate that resulting sensor can enter into the cancer cells such as A549 cells, and lead to the increase in luminescence, which is stronger than the sensor without the HCR-based signal amplification system. A linear relationship between the fluorescence intensity and the amount of A549 cells is observed, and the limit of detection of the sensor reaches about 280 A549 cells.

Multiple-metal compound materials have been demonstrated as high performance anode materials for energy storage. In this work, porous hollow polyhedron structured multicomponent sulfides and N -doped carbon-based composite (MnS-(ZnCo)S/N-C) is prepared through a gas-solid reaction using Mn, Zn, Co-based ternary metal−organic frameworks as precursor. As sodium ion batteries anode, MnS-(ZnCo)S/N-C exhibits impressive electrochemical performance, especially for the cycling performance at high current. At a current density of 2.0 A g −1, it delivers a capacity of 316 mAh g−1 within 400 cycles and a high capacity retention (92.9%) compared with that of the third cycle. Furthermore, the composite electrode maintains a capacity retention of 40% when the current raises from 0.1 to 10.0 A g−1 step by step. As a robust sodium storage host, this composite anode benefits from porous hollow polyhedron structures composed of primary nanoparticles, N doped C coating on primary particles, and multicomponent sulfides.

The internal drainage of roads is one of the most important measures to prevent water accumulation, especially on rainy days. Porous cement stabilized macadam is widely used as a skeleton porous material because of its excellent performance in road bases. So far, many scholars have researched the design and pavement performance of Porous cement stabilized macadam. However, minimal research has focused on the permeability and mechanical properties of Porous cement stabilized macadam materials subjected to freeze - thawing cycles in freezing areas. In this paper, through an indoor equivalent freeze–thawing cycle test, the effect of freezing and thawing cycles on the permeability performance and mechanical properties of two test groups was studied: a wet-frozen freeze–thawing test group and a water-immersion-frozen freeze–thawing test group. The changes in the void ratio, unconfined compressive strength, indirect tension strength, and compressive modulus of the resilience after repeated freeze–thawing cycles were examined. And the effects of the freeze–thawing cycles on permeability performance and mechanical properties under different conditions were evaluated. The experiment identified a minimal freeze–thawing cycle effect on the permeability performance of the porous cement stabilized macadam materials, for which the maximum increase in void ratio did not exceed 1.3%. However, it was bring the greater impact on the mechanical properties of the porous cement stabilized macadam after freeze–thawing cycle test. Unconfined compressive strength and indirect tension strength were reduced by a maximum of 37.94% and 53.49%, respectively, and the freeze–thawing cycle under saturated water conditions exhibited the greatest influence on the properties of the porous cement stabilized macadam as well as the unconfined compressive strength of the sample subjected to the water-immersion-frozen freeze–thawing test groups and wet-frozen freeze–thawing test groups. The unconfined compressive strength of the specimen was reduced by a maximum of 15.09%, whereas the indirect tension strength was relatively decreased by 28.57%. In addition, according to the test data to fit the corresponding function equations, it is proposed targeted improvement measures to provide theoretical guidance for practical engineering applications.

The exploration of low-cost, stable, and highly active noble-metal-free electrocatalyst for hydrogen evolution reaction (HER) in a wide pH range is crucial but still challenging task for renewable energy techniques. MoS2-based materials have been considered as a promising electrocatalyst for HER. However, corresponding studies have been hampered by the lack of effective routes to fully utilize the large number of inert basal plane for catalyzing HER, especially under alkaline media. Herein, a novel ammonia ions-guided-nitrogenization-phosphorization strategy is developed to prepare N and P co-doped MoS2 with active basal plane for efficient catalyzing HER with a quite low overpotential of 116 and 78 mV in 0.5 M H2SO4 and 1.0 M KOH to achieve a current density of 10 mA cm−2, respectively. Experimental studies and theoretical calculations confirm Mo-N-P sites in the basal plane of MoS2 can not only accelerate HER kinetics, but also result in energetic favorability and structure stability. Furthermore, outstanding performances are also obtained under both sea and river water, vastly broadening the application prospects.

Fenton reaction-based reactive oxygen species (ROS) generation provides a new idea for the design of ROS-mediated anticancer agents. Finding ways to increase iron uptake and to elevate the level of H2O2 in cells simultaneously is thus crucial to this strategy. Meanwhile, salicylic acid (SA) or its analogue, as the major metabolite of aspirin, has been reported to be closely associated with an intracellular redox-active product. In this work, a PEG-modified nanoscale coordination polymer (PFNC) via the self-assembly of 5-sulfosalicylic acid (SSA) with Fe3+ ions has been designed for the first time. The results show that the SSA dissociated from the PFNC can lead to the decrease of GSH and the accumulation of H2O2 in cancer cells, and thus elevate cellular ROS via the Fenton reaction. Owing to such intracellular oxidative stress, PFNC-induced ferroptotic cell death was further confirmed. In vitro cytotoxicity studies show that PFNCs display higher cytotoxicity on cancer cells than on normal cells. In vivo experiments further demonstrate that PFNCs not only possess high tumor accumulation, but also significantly inhibit the tumor growth without obvious damage toward the major organs. Based on the results, we expect that this work will provide an inspiration for understanding the role of SA, even aspirin, in the prevention of cancer.

Anode materials are demonstrated to essentially affect the electrochemical performance of sodium-ion batteries (SIBs), which are considered as a promising large-scale energy storage device. In this work, alloying ZnSxSe1-x (x = 0.24) and N doped carbon composite (ZnSxSe1-x/N-C (x = 0.24)) hierarchical nanospheres are prepared by selenizing the ZnS precursor. The corresponding X-ray diffraction and high-resolution transmission electron microscopy results prove the formation of an alloyed phase, resulting in a wider lattice compared with ZnS. Benefitting from the coexistence of S2− and Se2− in the ZnSxSe1-x lattice, the weaker Zn-Se bonds and wider lattice spacing facilitate ultrafast pseudocapacitive sodium storage capability and enhanced cycling stability, when ZnSxSe1-x/N-C is used as anode material for SIBs. At current of 1.0 A g−1, it delivers a capacity of 378 mAh g−1 after 130 cycles with capacity retention of 87.9%, which is much higher than 34.3% for the ZnS/N-C electrode. In addition, for the rate performance, it can maintain an impressive capacity of 233 mAh g−1 at 10.0 A g−1 with a capacity retention of 55.9% in comparison with the capacity at 0.2 A g−1. This work provides us common thoughts to enhance the electrochemical performance of transition metal chalcogenide anode through anion substitution.

Sodium ion batteries (SIBs) have been widely considered as a competitive alternative to construct low-cost and large-scale energy storage system. Unfortunately, low energy density and poor cycle life are main issues that need prompt solutions. Herein, an effective and controllable strategy, using metal–organic framework (MOF) precursors, was utilized to fabricate in situ N-doped carbon modified bimetallic sulfide hollow spheres with different metal ratios. When used as the anode material for SIBs, (Co0.5Ni0.5)9S8 solid-solution combined with in situ N-doped carbon ((Co0.5Ni0.5)9S8/N–C) is demonstrated to balance several aspects to deliver a superior electrochemical performance. (Co0.5Ni0.5)9S8/N–C exhibits the high specific capacity of 723.7 mA h g−1 at the 100th cycle at the current of 1.0 A g−1 and a high rate performance with the capacity of 569.1 mA h g−1 at 10 A g−1, yielding the high capacity retention of 60.2% compared with the capacity of 0.1 A g−1 (945.1 mA h g−1). The fast sodium storage capability is promoted by the capacitive contribution. Meanwhile, ex situ XRD is used to study the phase transition of the solid solution anode during the Na-storage process. The excellent performance can be attributed to the incorporation of Ni into the Co9S8 phase, in situ N–C coating and a stable hollow structure.

Chemo/chemodynamic synergistic therapy is a promising strategy to improve the antitumor effect. However, hypoxia and a limited amount of hydrogen peroxide (H2O2) in the tumor microenvironment (TME) severely restrict the therapeutic efficacy of this combined treatment. Herein, we report biodegradable doxorubicin (Dox)-loaded copper-metformin (Met) nanoscale coordination polymers (Dox@Cu-Met NPs), which exert a chemo/chemodynamic synergistic therapeutic effect by reducing oxygen (O2) consumption to promote H2O2 accumulation in the tumor. Inside tumor cells, Met can inhibit the consumption of O2 to relieve tumor hypoxia by suppressing mitochondrial respiration. The alleviated-tumor hypoxia can not only elevate H2O2 content via the Dox-activated cascade reaction of nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (NOXs) and superoxide dismutase (SOD), but also improve the efficacy of Dox. More importantly, the depletion of glutathione (GSH) accompanies the whole treatment process, which can realize the conversion of Cu2+ to Cu+ and boost reactive oxygen species (ROS) accumulation to improve chemodynamic therapy (CDT) efficacy. Meanwhile, Met is expected to cut off the energy supply by inhibiting respiration, leading to starvation therapy. In vivo investigations demonstrate that tumor growth is significantly inhibited through the enhanced chemo/chemodynamic synergistic treatment. This work provides a new paradigm for cancer therapy using an economical and straightforward method to construct a synergistic nanomedicine platform.

Recently, anode materials with synergistic sodium storage mechanisms of conversion combined with alloying reactions for sodium ion batteries (SIBs) have received widespread attention due to their high theoretical capacities. In this work, through reacting with an appropriate concentration of Sb

The exploration of highly active and stable noble-metal-free electrocatalysts for hydrogen and oxygen evolution reaction is a challenging task to achieve sustainable production of H2 through water splitting. Herein, we present the design and synthesis of a novel three-dimensional(3D)-networked heterogeneous nickel phosphide/sulfide electrocatalyst consisting of Ni2P strongly coupled with Ni3S2 in situ grown on Ni foam. Benefiting from the strong interfacial coupling effects between Ni2P and Ni3S2, large surface area, highly conductive Ni foam support, and the unique 3D open configuration, the optimal 3D-networked hybrid electrode exhibits superior electrocatalytic activity with extremely low overpotentials of 80 and 210 mV to deliver a current density of 10 mA cm−2 for HER and OER in 1.0 M KOH, respectively. Assembled as an electrolyzer for overall water splitting, this electrode delivers an impressive low onset potential of only 1.45 V and gives a current density of 10 mA cm−2 at a very low cell voltage of 1.50 V, which is dramatically superior to the current state-of-the-art electrocatalysts. In combination with density functional theory (DFT) calculations, this study demonstrates that the strong coupling interactions between Ni2P and Ni3S2 synergistically optimize the electronic structure and tune the hydrogen (or water) adsorption energy, thus significantly enhancing the overall electrochemical water-splitting activity. Our work might shed some new lights on the design and fabrication of efficient and robust three-dimensional hybrid electrode materials for a variety of electrochemical applications.

Core-multishelled structures with controlled chemical composition have attracted great interest due to their fascinating electrochemical performance. Herein, a metal-organic framework (MOF)-on-MOF self-templated strategy is used to fabricate okra-like bimetal sulfide (Fe

Diabetic kidney diseases (DKDs) are the primary diabetic microvascular complications and the main causes of end-stage renal disease (ESRD) worldwide. In China, the prevalence of diabetes has increased alongside the fast economic development. DKD has gradually become the chief cause of ESRD, and the prevalence of patients with type 2 diabetes mellitus and chronic kidney disease (CKD) is high. Patients with DKD have worse survival than those with comorbid diabetes on chronic hemodialysis. Hyperuricemia is an independent risk factor for DKD. The treatments of DKD and diabetes with comorbid CKD include the usual blood glucose and pressure controls, urinary albumin reduction, and treatment of complications. Currently, lowering uric acid is gradually gaining focus as a treatment. How is the rapid rise in the prevalence of diabetes affecting that of CKD in China? The problems of how to ensure early diagnosis, prevention, and delay of the development of DKD and diabetes with comorbid CKD require solutions. In this study, we summarize the epidemiology, diagnosis, and treatment of DKD and those of diabetes with comorbid CKD in China.

A new Pd/Ce based metal-organic framework is designed and synthesized as a self-sacrificial template for fabrication of an efficient catalyst for CO oxidation. The catalyst obtained by thermal annealing at 700 °C (Pd/CeO

As anode materials, the electrochemical performance of layered transition metal dichalcogenides (TMDs), can be improved with surface layer protection. In this study, flower-like MoSe2 nanostructures are easily obtained from a solvothermal reaction followed by an annealed process in inert atmosphere. Then the MoSe2 nanostructures are further treated in air at 350 °C, and amorphous MoO3 can be formed on MoSe2 surfaces, resulting into MoSe2/MoO3 heterogeneous nanostructures. The MoSe2/MoO3 composite, as anode materials for sodium ion batteries (SIBs), shows better performance than those of pristine MoSe2, which includes charge/discharge capacity, cycling stability and rate capability. At low current of 50 mA g−1, the discharge capacity can reach as high as 729 mAh g−1. In addition, even at high current of 10 A g−1, the discharge capacity maintains at 314 mAh g−1. At high currents of 1000 and 2000 mA g−1, after 200 cycles, the capacity retention can be kept at 101.9% and 99.5%, respectively. The enhanced performance of MoSe2/MoO3 heterogeneous nanostructures can be attributed to the amorphous MoO3 surface layer, which prevents selenium dissolution and subsequently improves the cycle performance and increases sodiation/desodiation kinetics because of the amorphous nature.

Hypovitaminosis D is common in chronic kidney disease (CKD) and is associated with endothelial dysfunction and cardiovascular events. This study aimed to investigate the effects of vitamin D supplementation on endothelial dysfunction in non-dialysis CKD patients. Seventy-one non-dialysis CKD patients with low vitamin D (serum 25(OH)D