Iron oxide nanoparticles(IONPs)have wide applications in the biomedical field due to their outstanding physical and chemical properties.However,the potential adverse effects and relatedmechanisms of IONPs in human org...Iron oxide nanoparticles(IONPs)have wide applications in the biomedical field due to their outstanding physical and chemical properties.However,the potential adverse effects and relatedmechanisms of IONPs in human organs,especially the lung,are still largely ignored.In this study,we found that group-modified IONPs(carboxylated,aminated and silica coated)induce slight lung cell damage(in terms of the cell cycle,reactive oxygen species(ROS)production,cell membrane integrity and DNA damage)at a sublethal dosage.However,aminated IONPs could release more iron ions in the lysosome than the other two types of IONPs,but the abnormally elevated iron ion concentration did not induce ferroptosis.In-triguingly,amino-modified IONPs aggravated the accumulation of intracellular peroxides induced by the ferroptosis activator RSL3 and thus caused ferroptosis in vitro,and the coadministration of amino-modified IONPs and RSL3 induced more severe lung injury in vivo.Therefore,our data revealed that the surface functionalization of IONPs plays an important role in determining their potential pulmonary toxicity,as surface modification influences their degradation behavior.These results provide guidance for the design of future IONPs and the corresponding safety evaluations and predictions.展开更多
During the continuous casting process of high-Mn high-Al steels,various types of gases such as Ar need to escape through the top of the mold.In which,the behavior of bubbles traversing the liquid slag serves as a rest...During the continuous casting process of high-Mn high-Al steels,various types of gases such as Ar need to escape through the top of the mold.In which,the behavior of bubbles traversing the liquid slag serves as a restrictive link,closely associated with viscosity and the thickness of liquid slag.In contrast to two-dimensional surface observation,three-dimensional(3D)analysis method can offer a more intuitive,accurate,and comprehensive information.Therefore,this study employs a 3D X-ray microscope(3D-XRM)to obtained spatial distribution and 3D morphological characteristics of residual bubbles in mold flux under different basicity of liquid slag,different temperatures,and different holding times.The results indicate that as basicity of slag increases from 0.52 to 1.03,temperature increases from 1423 to 1573 K,the viscosity of slag decreases,the floating rate of bubbles increases.In addition,when holding time increases from 10 to 30 s,the bubbles floating distance increases,and the volume fraction and average equivalent sphere diameter of the bubbles solidified in the mold flux gradually decreases.In one word,increasing the basicity,temperature,and holding time leading to an increase in the removal rate of bubbles especially for the large.These findings of bubbles escape behavior provide valuable insights into optimizing low basicity mold flux for high-Mn high-Al steels.展开更多
BACKGROUND Diabetic cognitive dysfunction(DCD)is one of the chronic complications of diabetes,but its mechanism is currently unknown.Studies have shown that mitochondrial fission mediated by calcium overload is an imp...BACKGROUND Diabetic cognitive dysfunction(DCD)is one of the chronic complications of diabetes,but its mechanism is currently unknown.Studies have shown that mitochondrial fission mediated by calcium overload is an important mechanism of DCD.Blocking calcium overload and restoring calcium homeostasis are key steps in treatment.Transient receptor potential melastatin 7(TRPM7)is a novel player in causing calcium overload.Our previous studies have shown that genetic silencing of TRPM7 in type 1 diabetic rats leads to significant improvements in cognitive function,but the specific mechanism remains unclear.Troxerutin,extracted from the flowers of Sophora japonica,is one of the derivatives of rutin and has been shown to have neuroprotective effects.However,its association with TRPM7 remains unclear.AIM To use animal and cellular models,we investigated whether TRPM7 mediated mitochondrial fission by upregulation of calcineurin(CaN)/dynamin-related protein 1(Drp1)ser637 in DCD,and whether Troxerutin improved DCD by inhibiting TRPM7-mediated mitochondrial division.METHODS In this study,we used db/db mice and hippocampal neuronal cell lines(HT22)treated with high-concentration glucose as our study subjects.We evaluated cognitive function using Morris water maze,novel object recognition tasks,and Nesting tests.We observed mitochondrial morphology using transmission electron microscopy and measured mitochondrial energy metabolism indicators using a spectrophotometer.We also detected mRNA and protein expression of TRPM7,CaN,p-Drp1^(ser637),caspase-3,B-cell lymphoma 2 associated X protein,and B-cell lymphoma 2 using quantitative real-time polymerase chain reaction,western blotting,and immunofluorescence.RESULTS In the db/db diabetic mice with cognitive dysfunction,as well as in hippocampal neurons exposed to high-concentration glucose,TRPM7 and CaN expression were upregulated,phosphorylated Drp1^(ser637)expression was downregulated,and mitochondrial fission was increased.By modulating(inhibiting or overexpressing)TRPM7,it was further validated that TRPM7 activates the CaN/Drp1^(ser637)pathway,resulting in an increase in mitochondrial fission and neuronal cell apoptosis.Troxerutin downregulated TRPM7/CaN/Drp1^(ser637),reduced mitochondrial fission,and improved DCD.CONCLUSION TRPM7 promotes mitochondrial fission via the CaN/Drp1^(ser637)pathway.Troxerutin improves mitochondrial function and reduces neuronal damage by inhibiting this pathway,suggesting TRPM7 as a potential therapeutic target for DCD.展开更多
Sustained inflammatory responses are closely related to various severe diseases,and inhibiting the excessive activation of inflammasomes and pyroptosis has significant implications for clinical treatment.Natural produ...Sustained inflammatory responses are closely related to various severe diseases,and inhibiting the excessive activation of inflammasomes and pyroptosis has significant implications for clinical treatment.Natural products have garnered considerable concern for the treatment of inflammation.Huanglian-Wumei decoction(HLWMD)is a classic prescription used for treating inflammatory diseases,but the necessity of their combination and the exact underlying anti-inflammatory mechanism have not yet been elucidated.Inspired by the supramolecular self-assembly strategy and natural drug compatibility theory,we successfully obtained berberine(BBR)-chlorogenic acid(CGA)supramolecular(BCS),which is an herbal pair from HLWMD.Using a series of characterization methods,we confirmed the self-assembly mechanism of BCS.BBR and CGA were self-assembled and stacked into amphiphilic spherical supramolecules in a 2:1 molar ratio,driven by electrostatic interactions,hydrophobic interactions,andπ–πstacking;the hydrophilic fragments of CGA were outside,and the hydrophobic fragments of BBR were inside.This stacking pattern significantly improved the anti-inflammatory performance of BCS compared with that of single free molecules.Compared with free molecules,BCS significantly attenuated the release of multiple inflammatory mediators and lipopolysaccharide(LPS)-induced pyroptosis.Its anti-inflammatory mechanism is closely related to the inhibition of intracellular nuclear factor-kappaB(NF-κB)p65 phosphorylation and the noncanonical pyroptosis signalling pathway mediated by caspase-11.展开更多
Bacterial pneumonia is one of the most common infectious diseases,a great threat to the health of children and the elderly.In the clinic,due to the extensive use of antibiotics,multi-drug-resistant bacteria have incre...Bacterial pneumonia is one of the most common infectious diseases,a great threat to the health of children and the elderly.In the clinic,due to the extensive use of antibiotics,multi-drug-resistant bacteria have increased in large numbers,seriously affects the treatment of patients with bacterial pneumonia.With the development of nanomedicine,it shows great potential in the treatment of bacterial pneumonia.In this review,it initially comprehensively describes the pathological process of bacterial pneumonia and the current status of its clinical treatment.Then it summarizes the strategies of nanomedicine for the treatment of bacterial pneumonia,including inorganic nanomaterials,polymer nanoparticles,natural source nanomaterials and artificial antimicrobial peptides,with a focus on novel nanomaterials for the treatment of bacterial pneumonia(biomimetic nanomaterials,nanovaccines and genetically engineered nanomaterials).Finally,the prospect of nanomedicine for bacterial pneumonia therapy is discussed in the hope of providing new ideas for the clinical treatment of bacterial pneumonia.展开更多
Photo-Cross-Linkable hydrogel has attracted immense interest in the regeneration of bone repair and regeneration strategies due to its superior biocompatibility and tunable mechanical properties.Recently,Nb was report...Photo-Cross-Linkable hydrogel has attracted immense interest in the regeneration of bone repair and regeneration strategies due to its superior biocompatibility and tunable mechanical properties.Recently,Nb was reported to strongly promote the bone regeneration process via an accelerated osteoblast-modulated alkaline phosphatase activity mechanism.In particular,Nb2C MXenes have drawn widespread attention due to their excellent biocompatibility and ability to induce bone formation.However,the easy agglomeration of Nb2C nanosheets and subsequent low cell endocytosis efficacy greatly suppressed the osteogenesis effect.In this study,a subtractive nanopore-engineered Nb2C MXene was prepared through a microwave combustion method,gelatin methacrylate was used as the carrier hydrogel,and the photo-triggered Porous-Nb2C@GelMA hydrogel was fabricated by a photo-triggered process.The pore-forming strategy not only successfully improved the distribution of Nb2C and formed more homogenous Porous-Nb2C@GelMA hydrogels but also guided bone marrow mesenchymal stem cells(BMSCs)toward osteoblast differentiation.Porous Nb2C provided convenient cellular grasping and endocytosis for BMSCs,which further created a favorable environment for differentiation and osteogenesis.This,in turn,leads to an increase in the expression of osteogenic markers,such as ALP and ARS,as well as osteogenic factors,such as BMP-2,COL-1,OCN,and OPN.Consequently,enhancing the regenerative microenvironment by incorporating porous Nb2C composite hydrogels shows promise for application in bone regeneration.展开更多
Owing to the lack of matching commercial welding wires,the development of wire arc additive manufacturing(WAAM)for most aluminum alloys is hindered.A wire-powder synchronous arc additive manufacturing(WPAAM)was propos...Owing to the lack of matching commercial welding wires,the development of wire arc additive manufacturing(WAAM)for most aluminum alloys is hindered.A wire-powder synchronous arc additive manufacturing(WPAAM)was proposed to prepare the target Al-Si-Mg aluminum alloy.Based on the synchronous deposition of AlSi_(12) wire and pure Mg powder,the deposition width of the WPAAMed thin-wall was increased by 61% compared with that of WAAMed thin-wall using AlSi_(12) wire,and the machining allowance was reduced by 81%.The added Mg powder benefited to form refined equiaxed grains,and reduced the average grain size of the WPAAMed thin-wall to 47.1μm,showing a decrease of 23.8% relatively to that of the WAAMed thin-wall.Besides,Mg reacted with Si to form Mg_(2)Si strengthening phases.The mechanical properties tests showed that the ultimate tensile strength and elongation of the WPAAMed thin-wall increased up to 174.5 MPa and 4.1%,reaching 92% and 60% those of the WAAMed thin-wall,respectively.展开更多
Acute lung injury(ALI)was characterized by excessive reactive oxygen species(ROS)levels and inflammatory response in the lung.Scavenging ROS could inhibit the excessive inflammatory response,further treating ALI.Herei...Acute lung injury(ALI)was characterized by excessive reactive oxygen species(ROS)levels and inflammatory response in the lung.Scavenging ROS could inhibit the excessive inflammatory response,further treating ALI.Herein,we designed a novel nanozyme(P@Co)comprised of polydopamine(PDA)nanoparticles(NPs)loading with ultra-small Co,combining with near infrared(NIR)irradiation,which could efficiently scavenge intracellular ROS and suppress inflammatory responses against ALI.For lipopolysaccharide(LPS)induced macrophages,P@Co+NIR presented excellent antioxidant and anti-inflammatory capacities through lowering intracellular ROS levels,decreasing the expression levels of interleukin-6(IL-6)and tumor necrosis factor-α(TNF-α)as well as inducing macrophage M2 directional polarization.Significantly,it displayed the outstanding activities of lowering acute lung inflammation,relieving diffuse alveolar damage,and up-regulating heat shock protein 70(HSP70)expression,resulting in synergistic enhanced ALI therapy effect.It offers a novel strategy for the clinical treatment of ROS related diseases.展开更多
Objective:To evaluate the effects of Wuhua herbal tea on chronic unpredictable mild stress(CUMS)-induced depression and explore its mechanism of action in combating depression.Methods:We tested the antidepressant effe...Objective:To evaluate the effects of Wuhua herbal tea on chronic unpredictable mild stress(CUMS)-induced depression and explore its mechanism of action in combating depression.Methods:We tested the antidepressant effects of Wuhua herbal tea in a rat model of CUMS-induced depression using fluoxetine as a positive control.The rats were divided into four groups:control group,model group,fluoxetine group,and Wuhua herbal tea group.The rats underwent body weight measurements,sucrose preference test,and open-field test.Enzyme-linked immunosorbent assay kits were used to detect the serum levels of serotonin,dopamine,adrenocorticotropic hormone(ACTH),corticosterone,norepinephrine,and interleukin-6.Intergroup comparisons and detection of brain-derived neurotrophic factor(BDNF),cAMP-response element binding protein(CREB),Janus kinase 2(JAK2),and signal transducer and activator of transcription 3(STAT3)mRNA expression in the hippocampus were performed using RTPCR.Immunohistochemistry was used to identify the expression of phosphorylated JAK2(p-JAK2)and phosphorylated STAT3(p-STAT3)proteins in hippocampal paraffin sections of CUMS rats.Results:Compared with the control group,the model group rats had depressive tendencies,exhibiting low vitality and interest in various behavioral indicators which were signs of despair.The Wuhua herbal tea group statistically increased the levels of serotonin and dopamine in the serum of CUMS rats to varying degrees(P=.015 and P=.002);reduced serum levels of ACTH,corticosterone,norepinephrine,and interleukin-6(all P<.05);and decreased mRNA expression of BDNF,CREB,JAK2,and STAT3 in the hippocampus(all P<.05);and decreased p-STAT3 protein levels(P=.006).Conclusion:Wuhua herbal tea shows antidepressant potential in CUMS rats by modulating the HPA axis and inhibiting JAK2-STAT3 overactivation,alleviating neuroinflammation.It also restores BDNF-CREB pathway function,reducing depressive symptoms.展开更多
Interbody fusion is recognized as the golden standard of surgical intervention for degenerative disc disease(DDD).Interbody fusion cage made of polyetheretherketone(PEEK)is commonly used in lumbar interbody fusion sur...Interbody fusion is recognized as the golden standard of surgical intervention for degenerative disc disease(DDD).Interbody fusion cage made of polyetheretherketone(PEEK)is commonly used in lumbar interbody fusion surgery in the treatment of DDD worldwide.However,there are some limitations of PEEK including their bio-inert nature and impediment to host bone integration.This study aimed to evaluate the degradation profile and osteoinductive potential of biodegradable Mg-Zn-Nd-Zr cages with/without micro-arc oxidation(MAO)coatings.The Mg-Zn-Nd-Zr alloy cages,whether coated with MAO or not,demonstrated commendable biocompatibility and biomechanical properties.Immersion and electrochemical tests show better corrosion resistance of MAO coatings in vitro.mRNA sequencing,RT-qPCR and Western blotting revealed that Mg-Zn-Nd-Zr and Mg-Zn-Nd-Zr/MAO had a better effectiveness on osteoinductivity.In vivo evaluations in ovine models over 12 weeks and 24 weeks post-implantation revealed radiological and histological evidence of enhanced bone formation adjacent to the Mg-Zn-Nd-Zr alloy cages compared to PEEK counterparts.Moreover,the MAO-coated cages exhibited a reduced propensity for gas formation.The Mg-Zn-Nd-Zr alloy is as a superior osteoinductive material compared with PEEK,with the MAO coating offering an advantage in mitigating gas production.Nonetheless,further research is warranted to refine the alloy's composition or surface treatments,particularly to address the challenges associated with rapid gas evolution during the early post-implantation period.展开更多
Purpose–The brake pipe system was an essential braking component of the railway freight trains,but the existing E-type sealing rings had problems such as insufficient low-temperature resistance,poor heat stability an...Purpose–The brake pipe system was an essential braking component of the railway freight trains,but the existing E-type sealing rings had problems such as insufficient low-temperature resistance,poor heat stability and short service life.To address these issues,low-phenyl silicone rubber was prepared and tested,and the finite element analysis and experimental studies on the sealing performance of its sealing rings were carried out.Design/methodology/approach–The low-temperature resistance and thermal stability of the prepared lowphenyl silicone rubber were studied using low-temperature tensile testing,differential scanning calorimetry,dynamic thermomechanical analysis and thermogravimetric analysis.The sealing performance of the lowphenyl silicone rubber sealing ring was studied by using finite element analysis software abaqus and experiments.Findings–The prepared low-phenyl silicone rubber sealing ring possessed excellent low-temperature resistance and thermal stability.According to the finite element analysis results,the finish of the flange sealing surface and groove outer edge should be ensured,and extrusion damage should be avoided.The sealing rings were more susceptible to damage in high compression ratio and/or low-temperature environments.When the sealing effect was ensured,a small compression ratio should be selected,and rubbers with hardness and elasticity less affected by temperature should be selected.The prepared low-phenyl silicone rubber sealing ring had zero leakage at both room temperature(RT)and�508C.Originality/value–The innovation of this study is that it provides valuable data and experience for the future development of the sealing rings used in the brake pipe flange joints of the railway freight cars in China.展开更多
Infectious wound healing is complicated with and limited by infection and oxidative stress at the wound site.In recent years,various evidences suggest that nanozymes with multiple enzymatic activities have enabled the...Infectious wound healing is complicated with and limited by infection and oxidative stress at the wound site.In recent years,various evidences suggest that nanozymes with multiple enzymatic activities have enabled the development of novel strategies for infectious wound healing.In this study,epigallocatechin gallate loaded polydopamine(P@E)was developed to act as a potent reactive oxygen species(ROS)scavenger for scavenging ROS,alleviating inflammatory responses,and promoting infectious wound healing.Combining with near infrared(NIR)irradiation,P@E presented excellent antibacterial ability of Escherichia coli(E.coli,93.6%)and methicillin-resistant Staphylococcus aureus(MRSA,87.6%).Specifically,P@E+NIR exhibited the most potent antioxidant,anti-inflammatory and cell proliferation behaviors through downregulating intracellular ROS levels(81.9%and 94.3%for NIH3T3 and RAW264.7 respectively)and inducible nitric oxide synthase(iNOS)expression level(55.7%),and up-regulating the expression levels of arginase-1(Arg-1,71.4%),heat shock protein 70(HSP70,48.6%)and platelet endothelial cell adhesion molecule(CD31,35.3%)compared to control group.Meanwhile,it also efficiently induced M2 directional polarization of lipopolysaccharide induced murine macrophages to achieve anti-inflammation,indicated by the down-regulation of CD86(86.2%),and up-regulation of CD206(85.6%).Significantly,it was also observed that P@E+NIR presented the excellent behaviors of inhibiting wound infection,alleviating wound inflammation,as well as promoting skin tissue repairing.Altogether,it has developed the strategy of using P@E combining with NIR irradiation for the synergistic enhanced healing of infectious skin wound,which can serve as a promising therapeutic strategy for its clinical treatment.展开更多
Purpose–Type-120 relief valves are critical components of locomotive braking systems,and they rapidly discharge the air pressure during brake release to enable swift pressure relief.In order to develop type-120 relie...Purpose–Type-120 relief valves are critical components of locomotive braking systems,and they rapidly discharge the air pressure during brake release to enable swift pressure relief.In order to develop type-120 relief valve rubber diaphragms with long life and high performance,the damaged faulty samples were analyzed and studied.Design/methodology/approach–Finite element analysis(FEA)was used to investigate the stress distribution and failure mechanism of the rubber diaphragms within the type-120 relief valves under dynamic loading conditions.The Ogden hyperelastic constitutive model was used to fit the diaphragm data obtained from the uniaxial tensile tests,and its suitability for the modeling of large deformations was confirmed.Findings–The FEA results indicated that,when the rubber diaphragms reached their maximum deformation,the peak stress on their upper surfaces was 5.44 MPa.Thus,this region is highly susceptible to fatigue damage.The service life of the rubber diaphragms could be extended by using rubber compounds with high tensile moduli or a fabric-reinforced rubber diaphragm.Originality/value–This study provides valuable data and experience for the development of the rubber diaphragms in the type-120 valves and other long-life rubber products in the railway field.展开更多
The heredity of clusters in rapidly cooled(Zr_(50)Cu_(50))_(100-x)Al_x melts and its correlation with glass-forming ability(GFA)are studied via molecular dynamics simulations.Pair distribution function and the largest...The heredity of clusters in rapidly cooled(Zr_(50)Cu_(50))_(100-x)Al_x melts and its correlation with glass-forming ability(GFA)are studied via molecular dynamics simulations.Pair distribution function and the largest standard cluster(LSC)are adopted to characterize the local atomic structures in the(Zr_(50)Cu_(50))_(100-x)Al_(x)systems.The[12/555]icosahedra and their medium-range order(IMRO)play an important role in forming(Zr_(50)Cu_(50))_(100-x)Al_(x)metallic glasses(MGs).The fraction of[12/555],the number of IMRO,and the maximum size of IMRO in MGs increase significantly with increasing x.A tracking study further reveals that the configuration heredity of icosahedral clusters starts from supercooled liquids.No direct correlation exists between the GFA and the onset temperature of continuous or stated heredity.Instead,a larger hereditary supercooled degree of icosahedra matches with better GFA of Al-doped Zr_(50)Cu_(50)alloys.展开更多
The Joule-Thomson effect is one of the important thermodynamic properties in the system relevant to gas switching reforming with carbon capture and storage(CCS). In this work, a set of apparatus was set up to determin...The Joule-Thomson effect is one of the important thermodynamic properties in the system relevant to gas switching reforming with carbon capture and storage(CCS). In this work, a set of apparatus was set up to determine the Joule-Thomson effect of binary mixtures(CO_(2)+ H_(2)). The accuracy of the apparatus was verified by comparing with the experimental data of carbon dioxide. The Joule-Thomson coefficients(μ_(JT)) for(CO_(2)+ H_(2)) binary mixtures with mole fractions of carbon dioxide(x_(CO_(2))= 0.1, 0.26, 0.5,0.86, 0.94) along six isotherms at various pressures were measured. Five equations of state EOSs(PR,SRK, PR, BWR and GERG-2008 equation) were used to calculate the μ_(JT)for both pure systems and binary systems, among which the GERG-2008 predicted best with a wide range of pressure and temperature.Moreover, the Joule-Thomson inversion curves(JTIC) were calculated with five equations of state. A comparison was made between experimental data and predicted data for the inversion curve of CO_(2). The investigated EOSs show a similar prediction of the low-temperature branch of the JTIC for both pure and binary systems, except for the BWRS equation of state. Among all the equations, SRK has the most similar result to GERG-2008 for predicting JTIC.展开更多
Purpose–The type 120 emergency valve is an essential braking component of railway freight trains,butcorresponding diaphragms consisting of natural rubber(NR)and chloroprene rubber(CR)exhibit insufficientaging resista...Purpose–The type 120 emergency valve is an essential braking component of railway freight trains,butcorresponding diaphragms consisting of natural rubber(NR)and chloroprene rubber(CR)exhibit insufficientaging resistance and low-temperature resistance,respectively.In order to develop type 120 emergency valverubber diaphragms with long-life and high-performance,low-temperatureresistant CR and NR were processed.Design/methodology/approach–The physical properties of the low-temperature-resistant CR and NRwere tested by low-temperature stretching,dynamic mechanical analysis,differential scanning calorimetryand thermogravimetric analysis.Single-valve and single-vehicle tests of type 120 emergency valves werecarried out for emergency diaphragms consisting of NR and CR.Findings–The low-temperature-resistant CR and NR exhibited excellent physical properties.The elasticityand low-temperature resistance of NR were superior to those of CR,whereas the mechanical properties of thetwo rubbers were similar in the temperature range of 0℃–150℃.The NR and CR emergency diaphragms metthe requirements of the single-valve test.In the low-temperature single-vehicle test,only the low-temperaturesensitivity test of the NR emergency diaphragm met the requirements.Originality/value–The innovation of this study is that it provides valuable data and experience for futuredevelopment of type 120 valve rubber diaphragms.展开更多
In this study,the oxidation behavior of Ti42Al5Mn,Ti42Al5Mn0.5 W,Ti42Al5Mn0.5W0.1B,and Ti42Al5Mn0.8 W was investigated at 800℃.Due to the inability to form a dense protective Al2O_(3) layer,Ti42Al5Mn suffered severe ...In this study,the oxidation behavior of Ti42Al5Mn,Ti42Al5Mn0.5 W,Ti42Al5Mn0.5W0.1B,and Ti42Al5Mn0.8 W was investigated at 800℃.Due to the inability to form a dense protective Al2O_(3) layer,Ti42Al5Mn suffered severe spallation during oxidation at 800℃and the mass gain was significant.The intermediate layer between the scale and the substrate was first composed of Laves/Z phase but changed toα2/Z phase with prolonged oxidation.The intermediate layer with high Ti/Al ratio favors the forma-tion of a thick Al2O_(3)+TiO_(2) mixed layer in the oxide scale which is prone to initiate cracks and cause the spalling of oxides.The doping of W in TiO_(2) effectively inhibited its generation and promoted the for-mation of a dense Al2O_(3) layer,resulting in a significant improvement in the oxidation resistance of the alloy.Compared to Ti42Al5Mn alloy,Ti42Al5Mn0.8 W showed no spallation after 300 h cyclic oxidation and the kinetic curve changed from liner law to parabolic law.The intermediate layer of Ti42Al5Mn0.8 W alloy was composed of a single Laves phase and remained unchanged even after 1000 h oxidation at 800℃,offering a favorable basis for the generation of a stable protective oxide layer in the alloy.The addi-tion of 0.1 at.%B to Ti42Al5Mn0.5 W alloy refined its microstructure and further improved its spallation resistance to a level close to that of Ti42Al5Mn0.8 W alloy.展开更多
The Mn-based oxide cathode with enriched crystal phase structure and component diversity can provide the excellent chemistry structure for Na-ion batteries.Nevertheless,the broad application prospect is obstructed by ...The Mn-based oxide cathode with enriched crystal phase structure and component diversity can provide the excellent chemistry structure for Na-ion batteries.Nevertheless,the broad application prospect is obstructed by the sluggish Na^(+)kinetics and the phase transitions upon cycling.Herein,we establish the thermodynamically stable phase diagram of various Mn-based oxide composites precisely controlled by sodium content tailoring strategy coupling with co-doping and solid-state reaction.The chemical environment of the P2/P'3 and P2/P3 biphasic composites indicate that the charge compensation mechanism stems from the cooperative contribution of anions and cations.Benefiting from the no phase transition to scavenge the structure strain,P2/P'3 electrode can deliver long cycling stability(capacity retention of 73.8%after 1000 cycles at 10 C)and outstanding rate properties(the discharge capacity of 84.08 mA h g^(-1)at 20 C)than P2/P3 electrode.Furthermore,the DFT calculation demonstrates that the introducing novel P'3 phase can significantly regulate the Na^(+)reaction dynamics and modify the local electron configuration of Mn.The effective phase engineering can provide a reference for designing other high-performance electrode materials for Na-ion batteries.展开更多
Nicotinamide adenine dinucleotide(NADH)regeneration is necessary for the sustainable application of enzymatic industry.The Rh-based complex[Cp^(*)Rh(bpy)(H)]+has been widely used as an important mediator in NADH regen...Nicotinamide adenine dinucleotide(NADH)regeneration is necessary for the sustainable application of enzymatic industry.The Rh-based complex[Cp^(*)Rh(bpy)(H)]+has been widely used as an important mediator in NADH regeneration systems,but it is limited by complexity and high cost.Here,a Z-scheme was constructed by loading Rh onto carbon nitride nanosheets/carbon nitride quantum dots(CN-CNQD).The resultant catalyst achieved a high yield of NADH in a mediator-free(M-free)system of 0.283 mmol L^(−1) g^(−1) min^(−1),which is 5.29 times that of pure CN.ADH enzyme introduction experiments confirmed that the enzyme active product 1,4-NADH could reach 34.21%selectivity in the M-free system.Mechanism research revealed that the heterojunction between CNs and CNQDs improved the NADH regeneration activity in the traditional M-involved system,while Rh loading was proved to optimize the yield and selectivity of 1,4-NADH in M-free system.The immobilized Rh shows more competitiveness than[Cp^(*)Rh(bpy)(H)]^(+).This study contributes to the construction of an M-free system for further application in greener,lower-cost enzymatic processes.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22076212 and 22222611)the Youth Innovation Promotion Association of CAS(No.2021040).
文摘Iron oxide nanoparticles(IONPs)have wide applications in the biomedical field due to their outstanding physical and chemical properties.However,the potential adverse effects and relatedmechanisms of IONPs in human organs,especially the lung,are still largely ignored.In this study,we found that group-modified IONPs(carboxylated,aminated and silica coated)induce slight lung cell damage(in terms of the cell cycle,reactive oxygen species(ROS)production,cell membrane integrity and DNA damage)at a sublethal dosage.However,aminated IONPs could release more iron ions in the lysosome than the other two types of IONPs,but the abnormally elevated iron ion concentration did not induce ferroptosis.In-triguingly,amino-modified IONPs aggravated the accumulation of intracellular peroxides induced by the ferroptosis activator RSL3 and thus caused ferroptosis in vitro,and the coadministration of amino-modified IONPs and RSL3 induced more severe lung injury in vivo.Therefore,our data revealed that the surface functionalization of IONPs plays an important role in determining their potential pulmonary toxicity,as surface modification influences their degradation behavior.These results provide guidance for the design of future IONPs and the corresponding safety evaluations and predictions.
基金financially supported by the National Natural Science Foundation of China(Nos.52274315 and 52374320)the Fundamental Research Funds for the Central Universities(Nos.FRF-TP-22-011A1 and FRF-DF22-16)。
文摘During the continuous casting process of high-Mn high-Al steels,various types of gases such as Ar need to escape through the top of the mold.In which,the behavior of bubbles traversing the liquid slag serves as a restrictive link,closely associated with viscosity and the thickness of liquid slag.In contrast to two-dimensional surface observation,three-dimensional(3D)analysis method can offer a more intuitive,accurate,and comprehensive information.Therefore,this study employs a 3D X-ray microscope(3D-XRM)to obtained spatial distribution and 3D morphological characteristics of residual bubbles in mold flux under different basicity of liquid slag,different temperatures,and different holding times.The results indicate that as basicity of slag increases from 0.52 to 1.03,temperature increases from 1423 to 1573 K,the viscosity of slag decreases,the floating rate of bubbles increases.In addition,when holding time increases from 10 to 30 s,the bubbles floating distance increases,and the volume fraction and average equivalent sphere diameter of the bubbles solidified in the mold flux gradually decreases.In one word,increasing the basicity,temperature,and holding time leading to an increase in the removal rate of bubbles especially for the large.These findings of bubbles escape behavior provide valuable insights into optimizing low basicity mold flux for high-Mn high-Al steels.
基金Supported by the Natural Science Foundation of Hebei Province,No.H2021206187 and No.H2021206452.
文摘BACKGROUND Diabetic cognitive dysfunction(DCD)is one of the chronic complications of diabetes,but its mechanism is currently unknown.Studies have shown that mitochondrial fission mediated by calcium overload is an important mechanism of DCD.Blocking calcium overload and restoring calcium homeostasis are key steps in treatment.Transient receptor potential melastatin 7(TRPM7)is a novel player in causing calcium overload.Our previous studies have shown that genetic silencing of TRPM7 in type 1 diabetic rats leads to significant improvements in cognitive function,but the specific mechanism remains unclear.Troxerutin,extracted from the flowers of Sophora japonica,is one of the derivatives of rutin and has been shown to have neuroprotective effects.However,its association with TRPM7 remains unclear.AIM To use animal and cellular models,we investigated whether TRPM7 mediated mitochondrial fission by upregulation of calcineurin(CaN)/dynamin-related protein 1(Drp1)ser637 in DCD,and whether Troxerutin improved DCD by inhibiting TRPM7-mediated mitochondrial division.METHODS In this study,we used db/db mice and hippocampal neuronal cell lines(HT22)treated with high-concentration glucose as our study subjects.We evaluated cognitive function using Morris water maze,novel object recognition tasks,and Nesting tests.We observed mitochondrial morphology using transmission electron microscopy and measured mitochondrial energy metabolism indicators using a spectrophotometer.We also detected mRNA and protein expression of TRPM7,CaN,p-Drp1^(ser637),caspase-3,B-cell lymphoma 2 associated X protein,and B-cell lymphoma 2 using quantitative real-time polymerase chain reaction,western blotting,and immunofluorescence.RESULTS In the db/db diabetic mice with cognitive dysfunction,as well as in hippocampal neurons exposed to high-concentration glucose,TRPM7 and CaN expression were upregulated,phosphorylated Drp1^(ser637)expression was downregulated,and mitochondrial fission was increased.By modulating(inhibiting or overexpressing)TRPM7,it was further validated that TRPM7 activates the CaN/Drp1^(ser637)pathway,resulting in an increase in mitochondrial fission and neuronal cell apoptosis.Troxerutin downregulated TRPM7/CaN/Drp1^(ser637),reduced mitochondrial fission,and improved DCD.CONCLUSION TRPM7 promotes mitochondrial fission via the CaN/Drp1^(ser637)pathway.Troxerutin improves mitochondrial function and reduces neuronal damage by inhibiting this pathway,suggesting TRPM7 as a potential therapeutic target for DCD.
基金supported by the Project of National Natural Science Foundation of China(Grant No.:82274219 and 81930117)the Key Project of Traditional Chinese Medicine Technology Development Plan of Jiangsu Province,China(Grant No.:ZD202201)Jiangsu Province Postgraduate Scientific Research Practice and Innovation Plan Project,China(Grant Nos.:KYCX21_1735 and SJCX21_0679).
文摘Sustained inflammatory responses are closely related to various severe diseases,and inhibiting the excessive activation of inflammasomes and pyroptosis has significant implications for clinical treatment.Natural products have garnered considerable concern for the treatment of inflammation.Huanglian-Wumei decoction(HLWMD)is a classic prescription used for treating inflammatory diseases,but the necessity of their combination and the exact underlying anti-inflammatory mechanism have not yet been elucidated.Inspired by the supramolecular self-assembly strategy and natural drug compatibility theory,we successfully obtained berberine(BBR)-chlorogenic acid(CGA)supramolecular(BCS),which is an herbal pair from HLWMD.Using a series of characterization methods,we confirmed the self-assembly mechanism of BCS.BBR and CGA were self-assembled and stacked into amphiphilic spherical supramolecules in a 2:1 molar ratio,driven by electrostatic interactions,hydrophobic interactions,andπ–πstacking;the hydrophilic fragments of CGA were outside,and the hydrophobic fragments of BBR were inside.This stacking pattern significantly improved the anti-inflammatory performance of BCS compared with that of single free molecules.Compared with free molecules,BCS significantly attenuated the release of multiple inflammatory mediators and lipopolysaccharide(LPS)-induced pyroptosis.Its anti-inflammatory mechanism is closely related to the inhibition of intracellular nuclear factor-kappaB(NF-κB)p65 phosphorylation and the noncanonical pyroptosis signalling pathway mediated by caspase-11.
基金supported by the Joint Project on Regional High-Incidence Diseases Research of Guangxi Natural Science Foundation(Nos.2023GXNSFDA026023 and 2024GXNSFAA010089)the Key Research&Development Program of Guangxi(No.Gui Ke AB22080088)+2 种基金the National Natural Science Foundation of China(No.82360372)the First-class Discipline Innovation-driven Talent Program of Guangxi Medical Universitythe Major Talent Project of Guangxi Autonomous Region。
文摘Bacterial pneumonia is one of the most common infectious diseases,a great threat to the health of children and the elderly.In the clinic,due to the extensive use of antibiotics,multi-drug-resistant bacteria have increased in large numbers,seriously affects the treatment of patients with bacterial pneumonia.With the development of nanomedicine,it shows great potential in the treatment of bacterial pneumonia.In this review,it initially comprehensively describes the pathological process of bacterial pneumonia and the current status of its clinical treatment.Then it summarizes the strategies of nanomedicine for the treatment of bacterial pneumonia,including inorganic nanomaterials,polymer nanoparticles,natural source nanomaterials and artificial antimicrobial peptides,with a focus on novel nanomaterials for the treatment of bacterial pneumonia(biomimetic nanomaterials,nanovaccines and genetically engineered nanomaterials).Finally,the prospect of nanomedicine for bacterial pneumonia therapy is discussed in the hope of providing new ideas for the clinical treatment of bacterial pneumonia.
基金supported by the Natural Science Foundation of China(82202751,Derong Xu,82372478,Chuanli Zhou,62375249,U1803128,Meng Qiu)the Taishan Scholar Project(tsqn202211362,Chuanli Zhou,tsqn201909054,Meng Qiu)+1 种基金the Natural Science Foundation of Shandong Province(ZR2021MH020,Chuanli Zhou,ZR2022JQ22,Meng Qiu)the Fundamental Research Funds for the Central Universities(202341006,Meng Qiu)。
文摘Photo-Cross-Linkable hydrogel has attracted immense interest in the regeneration of bone repair and regeneration strategies due to its superior biocompatibility and tunable mechanical properties.Recently,Nb was reported to strongly promote the bone regeneration process via an accelerated osteoblast-modulated alkaline phosphatase activity mechanism.In particular,Nb2C MXenes have drawn widespread attention due to their excellent biocompatibility and ability to induce bone formation.However,the easy agglomeration of Nb2C nanosheets and subsequent low cell endocytosis efficacy greatly suppressed the osteogenesis effect.In this study,a subtractive nanopore-engineered Nb2C MXene was prepared through a microwave combustion method,gelatin methacrylate was used as the carrier hydrogel,and the photo-triggered Porous-Nb2C@GelMA hydrogel was fabricated by a photo-triggered process.The pore-forming strategy not only successfully improved the distribution of Nb2C and formed more homogenous Porous-Nb2C@GelMA hydrogels but also guided bone marrow mesenchymal stem cells(BMSCs)toward osteoblast differentiation.Porous Nb2C provided convenient cellular grasping and endocytosis for BMSCs,which further created a favorable environment for differentiation and osteogenesis.This,in turn,leads to an increase in the expression of osteogenic markers,such as ALP and ARS,as well as osteogenic factors,such as BMP-2,COL-1,OCN,and OPN.Consequently,enhancing the regenerative microenvironment by incorporating porous Nb2C composite hydrogels shows promise for application in bone regeneration.
基金supported by the National Natural Science Foundation of China(No.52205360)。
文摘Owing to the lack of matching commercial welding wires,the development of wire arc additive manufacturing(WAAM)for most aluminum alloys is hindered.A wire-powder synchronous arc additive manufacturing(WPAAM)was proposed to prepare the target Al-Si-Mg aluminum alloy.Based on the synchronous deposition of AlSi_(12) wire and pure Mg powder,the deposition width of the WPAAMed thin-wall was increased by 61% compared with that of WAAMed thin-wall using AlSi_(12) wire,and the machining allowance was reduced by 81%.The added Mg powder benefited to form refined equiaxed grains,and reduced the average grain size of the WPAAMed thin-wall to 47.1μm,showing a decrease of 23.8% relatively to that of the WAAMed thin-wall.Besides,Mg reacted with Si to form Mg_(2)Si strengthening phases.The mechanical properties tests showed that the ultimate tensile strength and elongation of the WPAAMed thin-wall increased up to 174.5 MPa and 4.1%,reaching 92% and 60% those of the WAAMed thin-wall,respectively.
基金financially supported by the Key Research&Development Program of Guangxi(No.GuiKeAB22080088)the Joint Project on Regional High-Incidence Diseases Research of Guangxi Natural Science Foundation(No.2023GXNSFDA026023)+3 种基金the Natural Science Foundation of Guangxi(No.2023JJA140322)the National Natural Science Foundation of China(No.82360372)the High-level Medical Expert Training Program of Guangxi“139 Plan Funding(No.G202003010)the Medical Appropriate Technology Development and Popularization and Application Project of Guangxi(No.S2020099)。
文摘Acute lung injury(ALI)was characterized by excessive reactive oxygen species(ROS)levels and inflammatory response in the lung.Scavenging ROS could inhibit the excessive inflammatory response,further treating ALI.Herein,we designed a novel nanozyme(P@Co)comprised of polydopamine(PDA)nanoparticles(NPs)loading with ultra-small Co,combining with near infrared(NIR)irradiation,which could efficiently scavenge intracellular ROS and suppress inflammatory responses against ALI.For lipopolysaccharide(LPS)induced macrophages,P@Co+NIR presented excellent antioxidant and anti-inflammatory capacities through lowering intracellular ROS levels,decreasing the expression levels of interleukin-6(IL-6)and tumor necrosis factor-α(TNF-α)as well as inducing macrophage M2 directional polarization.Significantly,it displayed the outstanding activities of lowering acute lung inflammation,relieving diffuse alveolar damage,and up-regulating heat shock protein 70(HSP70)expression,resulting in synergistic enhanced ALI therapy effect.It offers a novel strategy for the clinical treatment of ROS related diseases.
基金supported by the Traditional Chinese Medicine Intervention of Metabolic Diseases Research Project(90020165120003)the Key Laboratory of Health Cultivation of the Ministry of Education(2024-JYB-KYPT-002).
文摘Objective:To evaluate the effects of Wuhua herbal tea on chronic unpredictable mild stress(CUMS)-induced depression and explore its mechanism of action in combating depression.Methods:We tested the antidepressant effects of Wuhua herbal tea in a rat model of CUMS-induced depression using fluoxetine as a positive control.The rats were divided into four groups:control group,model group,fluoxetine group,and Wuhua herbal tea group.The rats underwent body weight measurements,sucrose preference test,and open-field test.Enzyme-linked immunosorbent assay kits were used to detect the serum levels of serotonin,dopamine,adrenocorticotropic hormone(ACTH),corticosterone,norepinephrine,and interleukin-6.Intergroup comparisons and detection of brain-derived neurotrophic factor(BDNF),cAMP-response element binding protein(CREB),Janus kinase 2(JAK2),and signal transducer and activator of transcription 3(STAT3)mRNA expression in the hippocampus were performed using RTPCR.Immunohistochemistry was used to identify the expression of phosphorylated JAK2(p-JAK2)and phosphorylated STAT3(p-STAT3)proteins in hippocampal paraffin sections of CUMS rats.Results:Compared with the control group,the model group rats had depressive tendencies,exhibiting low vitality and interest in various behavioral indicators which were signs of despair.The Wuhua herbal tea group statistically increased the levels of serotonin and dopamine in the serum of CUMS rats to varying degrees(P=.015 and P=.002);reduced serum levels of ACTH,corticosterone,norepinephrine,and interleukin-6(all P<.05);and decreased mRNA expression of BDNF,CREB,JAK2,and STAT3 in the hippocampus(all P<.05);and decreased p-STAT3 protein levels(P=.006).Conclusion:Wuhua herbal tea shows antidepressant potential in CUMS rats by modulating the HPA axis and inhibiting JAK2-STAT3 overactivation,alleviating neuroinflammation.It also restores BDNF-CREB pathway function,reducing depressive symptoms.
基金supported by the National Natural Science Foundation of China(82172392)the National Natural Science Foundation of China(82372401)+1 种基金the Beijing Natural Science Foundation(L202033)the Basic Applied Research Program of Liaoning Province of China(2022020347-JH2/1013)。
文摘Interbody fusion is recognized as the golden standard of surgical intervention for degenerative disc disease(DDD).Interbody fusion cage made of polyetheretherketone(PEEK)is commonly used in lumbar interbody fusion surgery in the treatment of DDD worldwide.However,there are some limitations of PEEK including their bio-inert nature and impediment to host bone integration.This study aimed to evaluate the degradation profile and osteoinductive potential of biodegradable Mg-Zn-Nd-Zr cages with/without micro-arc oxidation(MAO)coatings.The Mg-Zn-Nd-Zr alloy cages,whether coated with MAO or not,demonstrated commendable biocompatibility and biomechanical properties.Immersion and electrochemical tests show better corrosion resistance of MAO coatings in vitro.mRNA sequencing,RT-qPCR and Western blotting revealed that Mg-Zn-Nd-Zr and Mg-Zn-Nd-Zr/MAO had a better effectiveness on osteoinductivity.In vivo evaluations in ovine models over 12 weeks and 24 weeks post-implantation revealed radiological and histological evidence of enhanced bone formation adjacent to the Mg-Zn-Nd-Zr alloy cages compared to PEEK counterparts.Moreover,the MAO-coated cages exhibited a reduced propensity for gas formation.The Mg-Zn-Nd-Zr alloy is as a superior osteoinductive material compared with PEEK,with the MAO coating offering an advantage in mitigating gas production.Nonetheless,further research is warranted to refine the alloy's composition or surface treatments,particularly to address the challenges associated with rapid gas evolution during the early post-implantation period.
基金supported by the Science and Technology Research and Development Plan of the China State Railway Group Company Limited(No.Q2023J012).
文摘Purpose–The brake pipe system was an essential braking component of the railway freight trains,but the existing E-type sealing rings had problems such as insufficient low-temperature resistance,poor heat stability and short service life.To address these issues,low-phenyl silicone rubber was prepared and tested,and the finite element analysis and experimental studies on the sealing performance of its sealing rings were carried out.Design/methodology/approach–The low-temperature resistance and thermal stability of the prepared lowphenyl silicone rubber were studied using low-temperature tensile testing,differential scanning calorimetry,dynamic thermomechanical analysis and thermogravimetric analysis.The sealing performance of the lowphenyl silicone rubber sealing ring was studied by using finite element analysis software abaqus and experiments.Findings–The prepared low-phenyl silicone rubber sealing ring possessed excellent low-temperature resistance and thermal stability.According to the finite element analysis results,the finish of the flange sealing surface and groove outer edge should be ensured,and extrusion damage should be avoided.The sealing rings were more susceptible to damage in high compression ratio and/or low-temperature environments.When the sealing effect was ensured,a small compression ratio should be selected,and rubbers with hardness and elasticity less affected by temperature should be selected.The prepared low-phenyl silicone rubber sealing ring had zero leakage at both room temperature(RT)and�508C.Originality/value–The innovation of this study is that it provides valuable data and experience for the future development of the sealing rings used in the brake pipe flange joints of the railway freight cars in China.
基金financially supported by the Natural Science Foundation of Guangxi(Nos.2022GXNSFAA035505 and 2024GXNSFAA010164)the Key Research&Development Program of Guangxi(No.GuiKe2024AB08057)+1 种基金the Guangxi Medical and Health Suitable Technology Development and Popularization Applications Project(Nos.S2023093 and S2021084)the Major Talent Project of Guangxi Autonomous Region.
文摘Infectious wound healing is complicated with and limited by infection and oxidative stress at the wound site.In recent years,various evidences suggest that nanozymes with multiple enzymatic activities have enabled the development of novel strategies for infectious wound healing.In this study,epigallocatechin gallate loaded polydopamine(P@E)was developed to act as a potent reactive oxygen species(ROS)scavenger for scavenging ROS,alleviating inflammatory responses,and promoting infectious wound healing.Combining with near infrared(NIR)irradiation,P@E presented excellent antibacterial ability of Escherichia coli(E.coli,93.6%)and methicillin-resistant Staphylococcus aureus(MRSA,87.6%).Specifically,P@E+NIR exhibited the most potent antioxidant,anti-inflammatory and cell proliferation behaviors through downregulating intracellular ROS levels(81.9%and 94.3%for NIH3T3 and RAW264.7 respectively)and inducible nitric oxide synthase(iNOS)expression level(55.7%),and up-regulating the expression levels of arginase-1(Arg-1,71.4%),heat shock protein 70(HSP70,48.6%)and platelet endothelial cell adhesion molecule(CD31,35.3%)compared to control group.Meanwhile,it also efficiently induced M2 directional polarization of lipopolysaccharide induced murine macrophages to achieve anti-inflammation,indicated by the down-regulation of CD86(86.2%),and up-regulation of CD206(85.6%).Significantly,it was also observed that P@E+NIR presented the excellent behaviors of inhibiting wound infection,alleviating wound inflammation,as well as promoting skin tissue repairing.Altogether,it has developed the strategy of using P@E combining with NIR irradiation for the synergistic enhanced healing of infectious skin wound,which can serve as a promising therapeutic strategy for its clinical treatment.
基金supported by the Science and Technology Research and Development Plan of the China State Railway Group Company Limited(Grant No.N2023J053).
文摘Purpose–Type-120 relief valves are critical components of locomotive braking systems,and they rapidly discharge the air pressure during brake release to enable swift pressure relief.In order to develop type-120 relief valve rubber diaphragms with long life and high performance,the damaged faulty samples were analyzed and studied.Design/methodology/approach–Finite element analysis(FEA)was used to investigate the stress distribution and failure mechanism of the rubber diaphragms within the type-120 relief valves under dynamic loading conditions.The Ogden hyperelastic constitutive model was used to fit the diaphragm data obtained from the uniaxial tensile tests,and its suitability for the modeling of large deformations was confirmed.Findings–The FEA results indicated that,when the rubber diaphragms reached their maximum deformation,the peak stress on their upper surfaces was 5.44 MPa.Thus,this region is highly susceptible to fatigue damage.The service life of the rubber diaphragms could be extended by using rubber compounds with high tensile moduli or a fabric-reinforced rubber diaphragm.Originality/value–This study provides valuable data and experience for the development of the rubber diaphragms in the type-120 valves and other long-life rubber products in the railway field.
基金the National Natural Science Foundation of China(Grant No.51701071)the Natural Science Foundation of Hunan Province,China(Grant Nos.2018JJ3100 and 2018JJ2078)the Project of the Hunan Educational Department,China(Grant No.19B122)。
文摘The heredity of clusters in rapidly cooled(Zr_(50)Cu_(50))_(100-x)Al_x melts and its correlation with glass-forming ability(GFA)are studied via molecular dynamics simulations.Pair distribution function and the largest standard cluster(LSC)are adopted to characterize the local atomic structures in the(Zr_(50)Cu_(50))_(100-x)Al_(x)systems.The[12/555]icosahedra and their medium-range order(IMRO)play an important role in forming(Zr_(50)Cu_(50))_(100-x)Al_(x)metallic glasses(MGs).The fraction of[12/555],the number of IMRO,and the maximum size of IMRO in MGs increase significantly with increasing x.A tracking study further reveals that the configuration heredity of icosahedral clusters starts from supercooled liquids.No direct correlation exists between the GFA and the onset temperature of continuous or stated heredity.Instead,a larger hereditary supercooled degree of icosahedra matches with better GFA of Al-doped Zr_(50)Cu_(50)alloys.
基金supported by the National Natural Science Foundation of China (21878056)Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology (2019Z002)。
文摘The Joule-Thomson effect is one of the important thermodynamic properties in the system relevant to gas switching reforming with carbon capture and storage(CCS). In this work, a set of apparatus was set up to determine the Joule-Thomson effect of binary mixtures(CO_(2)+ H_(2)). The accuracy of the apparatus was verified by comparing with the experimental data of carbon dioxide. The Joule-Thomson coefficients(μ_(JT)) for(CO_(2)+ H_(2)) binary mixtures with mole fractions of carbon dioxide(x_(CO_(2))= 0.1, 0.26, 0.5,0.86, 0.94) along six isotherms at various pressures were measured. Five equations of state EOSs(PR,SRK, PR, BWR and GERG-2008 equation) were used to calculate the μ_(JT)for both pure systems and binary systems, among which the GERG-2008 predicted best with a wide range of pressure and temperature.Moreover, the Joule-Thomson inversion curves(JTIC) were calculated with five equations of state. A comparison was made between experimental data and predicted data for the inversion curve of CO_(2). The investigated EOSs show a similar prediction of the low-temperature branch of the JTIC for both pure and binary systems, except for the BWRS equation of state. Among all the equations, SRK has the most similar result to GERG-2008 for predicting JTIC.
基金funded by the Science and Technology Research and Development Plan of the China State Railway Group Company Limited(No.N2023J053).
文摘Purpose–The type 120 emergency valve is an essential braking component of railway freight trains,butcorresponding diaphragms consisting of natural rubber(NR)and chloroprene rubber(CR)exhibit insufficientaging resistance and low-temperature resistance,respectively.In order to develop type 120 emergency valverubber diaphragms with long-life and high-performance,low-temperatureresistant CR and NR were processed.Design/methodology/approach–The physical properties of the low-temperature-resistant CR and NRwere tested by low-temperature stretching,dynamic mechanical analysis,differential scanning calorimetryand thermogravimetric analysis.Single-valve and single-vehicle tests of type 120 emergency valves werecarried out for emergency diaphragms consisting of NR and CR.Findings–The low-temperature-resistant CR and NR exhibited excellent physical properties.The elasticityand low-temperature resistance of NR were superior to those of CR,whereas the mechanical properties of thetwo rubbers were similar in the temperature range of 0℃–150℃.The NR and CR emergency diaphragms metthe requirements of the single-valve test.In the low-temperature single-vehicle test,only the low-temperaturesensitivity test of the NR emergency diaphragm met the requirements.Originality/value–The innovation of this study is that it provides valuable data and experience for futuredevelopment of type 120 valve rubber diaphragms.
基金National Natural Science Foundation of China(Grant No.51971215).
文摘In this study,the oxidation behavior of Ti42Al5Mn,Ti42Al5Mn0.5 W,Ti42Al5Mn0.5W0.1B,and Ti42Al5Mn0.8 W was investigated at 800℃.Due to the inability to form a dense protective Al2O_(3) layer,Ti42Al5Mn suffered severe spallation during oxidation at 800℃and the mass gain was significant.The intermediate layer between the scale and the substrate was first composed of Laves/Z phase but changed toα2/Z phase with prolonged oxidation.The intermediate layer with high Ti/Al ratio favors the forma-tion of a thick Al2O_(3)+TiO_(2) mixed layer in the oxide scale which is prone to initiate cracks and cause the spalling of oxides.The doping of W in TiO_(2) effectively inhibited its generation and promoted the for-mation of a dense Al2O_(3) layer,resulting in a significant improvement in the oxidation resistance of the alloy.Compared to Ti42Al5Mn alloy,Ti42Al5Mn0.8 W showed no spallation after 300 h cyclic oxidation and the kinetic curve changed from liner law to parabolic law.The intermediate layer of Ti42Al5Mn0.8 W alloy was composed of a single Laves phase and remained unchanged even after 1000 h oxidation at 800℃,offering a favorable basis for the generation of a stable protective oxide layer in the alloy.The addi-tion of 0.1 at.%B to Ti42Al5Mn0.5 W alloy refined its microstructure and further improved its spallation resistance to a level close to that of Ti42Al5Mn0.8 W alloy.
基金supported by the National Natural Science Foundation of China (52173273)Fundamental Research Funds for the Central Universities (2022CX11013)+2 种基金Shanxi Province Science Foundation for Youths (No.202203021212391)the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi (No.2022L253)Institute Foundation Project of China Academy of Railway Sciences Corporation Limited Metals and Chemistry Research Institute (No.2023SJ02)。
文摘The Mn-based oxide cathode with enriched crystal phase structure and component diversity can provide the excellent chemistry structure for Na-ion batteries.Nevertheless,the broad application prospect is obstructed by the sluggish Na^(+)kinetics and the phase transitions upon cycling.Herein,we establish the thermodynamically stable phase diagram of various Mn-based oxide composites precisely controlled by sodium content tailoring strategy coupling with co-doping and solid-state reaction.The chemical environment of the P2/P'3 and P2/P3 biphasic composites indicate that the charge compensation mechanism stems from the cooperative contribution of anions and cations.Benefiting from the no phase transition to scavenge the structure strain,P2/P'3 electrode can deliver long cycling stability(capacity retention of 73.8%after 1000 cycles at 10 C)and outstanding rate properties(the discharge capacity of 84.08 mA h g^(-1)at 20 C)than P2/P3 electrode.Furthermore,the DFT calculation demonstrates that the introducing novel P'3 phase can significantly regulate the Na^(+)reaction dynamics and modify the local electron configuration of Mn.The effective phase engineering can provide a reference for designing other high-performance electrode materials for Na-ion batteries.
基金supported by the National Natural Science Foundation of China(No.21906056)Open Project of State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology(No.ESK202104)+1 种基金the Science and Technology Commission of Shanghai Municipality(No.22ZR1418600)Shanghai Municipal Science and Technology(No.20DZ2250400).
文摘Nicotinamide adenine dinucleotide(NADH)regeneration is necessary for the sustainable application of enzymatic industry.The Rh-based complex[Cp^(*)Rh(bpy)(H)]+has been widely used as an important mediator in NADH regeneration systems,but it is limited by complexity and high cost.Here,a Z-scheme was constructed by loading Rh onto carbon nitride nanosheets/carbon nitride quantum dots(CN-CNQD).The resultant catalyst achieved a high yield of NADH in a mediator-free(M-free)system of 0.283 mmol L^(−1) g^(−1) min^(−1),which is 5.29 times that of pure CN.ADH enzyme introduction experiments confirmed that the enzyme active product 1,4-NADH could reach 34.21%selectivity in the M-free system.Mechanism research revealed that the heterojunction between CNs and CNQDs improved the NADH regeneration activity in the traditional M-involved system,while Rh loading was proved to optimize the yield and selectivity of 1,4-NADH in M-free system.The immobilized Rh shows more competitiveness than[Cp^(*)Rh(bpy)(H)]^(+).This study contributes to the construction of an M-free system for further application in greener,lower-cost enzymatic processes.
