The intensive development of micro-/nanotechnologies offers a new route to construct sophisticated architectures of emerging soft electronics.Among the many classes of stretchable materials,micro-/nanostructured poly(...The intensive development of micro-/nanotechnologies offers a new route to construct sophisticated architectures of emerging soft electronics.Among the many classes of stretchable materials,micro-/nanostructured poly(dimethylsiloxane)(PDMS)has emerged as a vital building block based on its merits of flexibility,stretchability,simple processing,and,more importantly,high degrees of freedom of incorporation with other functional materials,including metals and semiconductors.The artificially designed geometries play important roles in achieving the desired mechanical and electrical performances of devices and thus show great potential for applications in the fields of stretchable displays,sensors and actuators as well as in health-monitoring device platforms.Meanwhile,novel lithographic methods to produce stretchable platforms with superb reliability have recently attracted research interest.The aim of this review is to comprehensively summarize the progress regarding micro-/nanostructured PDMS and their promising soft electronic applications.This review is concluded with a brief outlook and further research directions.展开更多
The research of superhydrophobic materials has attracted many researchers＇ attention due to its application value and prospects.In order to expand the serviceable range,people have investigated various superhydrophob...The research of superhydrophobic materials has attracted many researchers＇ attention due to its application value and prospects.In order to expand the serviceable range,people have investigated various superhydrophobic materials.The simple and easy preparation method has become the focus for superhydrophobic materials.In this paper,we present a program for preparing a rough surface on an aluminum foil,which possesses excellent hydrophobic properties after the treatment with low surface energy materials at high vacuum.The resulting contact angle is larger than 160° and the droplet cannot freeze on the surface above-10 ℃.Meanwhile,the modified aluminum foil with the thickness of less than 100 μm can be used as an ideal flexible applied material for superhydrophobicity/anti-icing.展开更多
Rolling contact fatigue performance is among the most important issues for applications of bearing steels.In this work,a recently developed surface modification technique,surface mechanical rolling treatment,was appli...Rolling contact fatigue performance is among the most important issues for applications of bearing steels.In this work,a recently developed surface modification technique,surface mechanical rolling treatment,was applied on a rare-earth addition bearing steel.And rolling contact fatigue behavior of treated samples was compared with that of as-received counterparts at different contacting stresses.The results demonstrated that a 700μm-thick gradient nanostructured surface layer is produced on samples by surface mechanical rolling treatment.The grain size decreases while the microhardness increases gradually with decreasing depth,reaching~23 nm and~10.2 GPa,respectively,at the top surface.Consequently,the rolling contact fatigue property is significantly enhanced.The characteristic life of treated samples is~3.2 times that of untreated counterparts according to Weibull curves at 5.6 GPa.Analyses of fatigue mechanisms demonstrated that the gradient nanostructured surface layer might not only retard material degradation and microcrack formation,but also prolong the steady-state elastic response stage under rolling contact fatigue.展开更多
High-pressure β-Sn germanium may transform into diverse metastable allotropes with distinctive nanostructures and unique physical properties via multiple pathways under decompression.However,the mechanism and transit...High-pressure β-Sn germanium may transform into diverse metastable allotropes with distinctive nanostructures and unique physical properties via multiple pathways under decompression.However,the mechanism and transition kinetics remain poorly understood.Here,we investigate the formation of metastable phases and nanostructures in germanium via controllable transition pathways of β-Sn Ge under rapid decompression at different rates.High-resolution transmission electron microscopy reveals three distinct metastable phases with the distinctive nanostructures:an almost perfect st12 Ge crystal,nanosized bc8/r8 structures with amorphous boundaries,and amorphous Ge with nanosized clusters (0.8–2.5 nm).Fast in situ x-ray diffraction and x-ray absorption measurements indicate that these nanostructured products form in certain pressure regions via distinct kinetic pathways and are strongly correlated with nucleation rates and electronic transitions mediated by compression rate,temperature,and stress.This work provides deep insight into the controllable synthesis of metastable materials with unique crystal symmetries and nanostructures for potential applications.展开更多
This study introduces a nanostructured MgO coating fabricated via anodization in a non-aqueous electrolyte,offering a novel approach to addressing the challenges of corrosion resistance and biofunctionality.The surfac...This study introduces a nanostructured MgO coating fabricated via anodization in a non-aqueous electrolyte,offering a novel approach to addressing the challenges of corrosion resistance and biofunctionality.The surface was characterized before and after immersion testing using field emission scanning electron microscopy(FESEM),energy-dispersive X-ray spectroscopy(EDX),and X-ray diffraction(XRD).Electrochemical impedance spectroscopy(EIS)and potentiodynamic polarization tests demonstrated a 2-fold reduction in the corrosion resistance compared to untreated magnesium.Biomineralization studies demonstrated the uniform formation of apatite with a Ca/P ratio of 1.35 on the nanostructured surface after 14 days in simulated body fluid(SBF),surpassing that of microstructured MgO.Hydrogen evolution decreased from 912±38μL cm^(-2)for untreated Mg to 615±32μL cm^(-2)for the Mg/MgO nanostructure and 545±29μL cm^(-2)for the Mg/Mg O/HA sample.These findings highlight the potential of nanostructured MgO coatings to advance Mg-based implants by providing enhanced corrosion protection,improved biomineralization,reduced hemolysis and increased cell viability,and reduced H_(2)generation.展开更多
Solid oxide cells(SOCs)are attractive electrochemical energy conversion/storage technologies for electricity/green hydrogen production because of the high efficiencies,all-solid structure,and superb reversibility.Neve...Solid oxide cells(SOCs)are attractive electrochemical energy conversion/storage technologies for electricity/green hydrogen production because of the high efficiencies,all-solid structure,and superb reversibility.Nevertheless,the widespread applications of SOCs are remarkably restricted by the inferior stability and high material costs induced by the high operational temperatures(600-800℃).Tremendous research efforts have been devoted to suppressing the operating temperatures of SOCs to decrease the overall costs and enhance the long-term durability.However,fuel electrodes as key components in SOCs suffer from insufficient(electro)catalytic activity and inferior impurity tolerance/redox resistance at reduced temperatures.Nanostructures and relevant nanomaterials exhibit great potential to boost the performance of fuel electrodes for low-temperature(LT)-SOCs due to the unique surface/interface properties,enlarged active sites,and strong interaction.Herein,an in-time review about advances in the design and fabrication of nanostructured fuel electrodes for LT-SOCs is presented by emphasizing the crucial role of nanostructure construction in boosting the performance of fuel electrodes and the relevant/distinct material design strategies.The main achievements,remaining challenges,and research trends about the development of nanostructured fuel electrodes in LT-SOCs are also presented,aiming to offer important insights for the future development of energy storage/conversion technologies.展开更多
High porosity and high brittleness are the main reasons that limit the long-term service life of the alumina-titanium oxide composite coating.Herein,a metastable nanostructured aluminatitanium oxide composite coating ...High porosity and high brittleness are the main reasons that limit the long-term service life of the alumina-titanium oxide composite coating.Herein,a metastable nanostructured aluminatitanium oxide composite coating with high density and high properties was synthesized by plasma spraying of TiO_(2)-Al composite powder.The main phases of the metastable nanostructured alumina-titanium oxide wereγ-Al_(2)O_(3),TiO and AlTiO_(2).The coating,as prepared,contains various metastable microstructures,such as fine-grained,intra-/inter-granular,and"self-locking"microstructures.These metastable microstruc-tures are important for the improvement of hardness and toughness of the coating.Compared with other alumina-based composite coatings,the metastable nanostructured aluminatitanium oxide composite coating showed the most impressive overall performance.The reinforcing and toughening mechanism of the metastable alumina-titanium oxide composite coating included fine grain strengthening and self-toughening of the metastable microstructure.展开更多
1.Introduction The synthesis of bulk nanostructured multiphase(NM)mate-rials with extreme properties such as high hardness and strength is one of the most interesting research topics in materials science and engineeri...1.Introduction The synthesis of bulk nanostructured multiphase(NM)mate-rials with extreme properties such as high hardness and strength is one of the most interesting research topics in materials science and engineering[1].At present,NM alloys can be produced by several synthesis methods,including sintering of nanocomposites[2,3],physical or chemical vapour deposition(PVD or CVD)[4],crystallization of metallic glasses[5],and severe plastic deforma-tion(SPD)[6-8].However,industry applications of bulk NM alloys produced by these methods are significantly restricted by their ge-ometrical and size limitations.Thus,the fabrication of large-scale NM alloys remains challenging.展开更多
The global burden of bacterial infections,exacerbated by antimicrobial resistance(AMR),necessitates innovative strategies.Bacterial protein vaccines offer promise by eliciting targeted immunity while circumventing AMR...The global burden of bacterial infections,exacerbated by antimicrobial resistance(AMR),necessitates innovative strategies.Bacterial protein vaccines offer promise by eliciting targeted immunity while circumventing AMR.However,their clinical translation is hindered by their inherently low immunogenicity,often requiring potent adjuvants and advanced delivery systems.Biomembrane nanostructures(e.g.,liposomes,exosomes,and cell membrane-derived nanostructures),characterized by superior biocompatibility,intrinsic targeting ability,and immune-modulating properties,could serve as versatile platforms that potentiate vaccine efficacy by increasing antigen stability,enabling codelivery of immunostimulants,and facilitating targeted delivery to lymphoid tissues/antigen-presenting cells.This intrinsic immunomodulation promotes robust humoral and cellular immune responses to combat bacteria.This review critically reviews(1)key biomembrane nanostructure classes for bacterial protein antigens,(2)design strategies leveraging biomembrane nanostructures to enhance humoral and cellular immune responses,(3)preclinical efficacy against diverse pathogens,and(4)translational challenges and prospects.Biomembrane nanostructure-driven approaches represent a paradigm shift in the development of next-generation bacterial protein vaccines against resistant infections.展开更多
The extrusion of Al-Si alloy powders with different particle sizes allows manufacture of different products with unique microstructures and therefore with unique mechanical properties. The effects of powder size on th...The extrusion of Al-Si alloy powders with different particle sizes allows manufacture of different products with unique microstructures and therefore with unique mechanical properties. The effects of powder size on the extrusion behavior and process defect of Al-18%Si alloy were studied by means of microscopy (optical, scanning electron) and density determination. The main objective of the work is to demonstrate the influence of the powder material characteristics on final density and quality of bar. The results show that the bigger the powder particles, the better the performance of cold compacting. The surface of alloy bar extruded from big particles has good quality without cracking. While the smaller the powder particles, the higher the density and the better the microstructure and mechanical properties. For practice application, the mixed powders are better than single powder.展开更多
Twisted multilayers of two-dimensional materials attract widespread research interest due to their intriguing electronic and optical properties related to their chiral symmetry breaking and moiréeffects.The two-d...Twisted multilayers of two-dimensional materials attract widespread research interest due to their intriguing electronic and optical properties related to their chiral symmetry breaking and moiréeffects.The two-dimensional transition metal dichalcogenide MoSe_(2) is a particularly promising material for twisted multilayers,capable of sustaining moiréexcitons.Here,we report on a rational bottomup synthesis approach for twisted MoSe_(2) flakes by chemical vapor transport(CVT).Screw dislocation-driven growth was forced by surface-fused SiO_(2)nanoparticles on the substrates that serve as potential nucleation points in low supersaturation condition.Thus,crystal growth by in-situ CVT under addition of MoCl_(5) leads to bulk 2H-MoSe_(2) in a temperature gradient from 900 to 820℃ with a dwell time of 96 h.Hexagonally shaped 2H-MoSe_(2) flakes were grown from 710 to 685℃ with a dwell time of 30 min on SiO_(2)@Al_(2)O_(3)(0001)substrates.Electron backscatter diffraction as well as electron microscopy reveals the screw dislocation-driven growth of triangular 3R-MoSe_(2) with individual step heights between 0.9 and 2.9 nm on SiO_(2)@Si(100)under the same conditions.Finally,twisted MoSe_(2) flakes exhibiting a twist angle of 19°with respect to the[010]zone axis could be synthesized.展开更多
The Ni-based alloy composite coatings reinforced by nanostructured Al2O3-40%TiO2 multiphase ceramic particles were prepared on the surface of 7005 aluminum alloy by plasma spray technology. The microstructure and trib...The Ni-based alloy composite coatings reinforced by nanostructured Al2O3-40%TiO2 multiphase ceramic particles were prepared on the surface of 7005 aluminum alloy by plasma spray technology. The microstructure and tribological properties of the composite coatings were researched. The results show that the composite coatings mainly consist of γ-Ni, α-Al2O3, γ-Al2O3 and rutile-TiO2 etc, and exhibit lower friction coefficients and wear losses than the Ni-based alloy coatings at different loads and speeds. The composite coating bears low contact stress at 3 N and its wear mechanism is micro-cutting wear. As loads increase to 6-12 N, the contact stress is higher than the elastic limit stress of worn surface, and the wear mechanisms change into multi-plastic deformation wear, micro-brittle fracture wear and abrasive wear. With the increase of speeds, the contact temperature of worn surface increases. The composite coating experiences multi-plastic deformation wear, fatigue wear and adhesive wear.展开更多
The roots of 200 one-year-old Changbai Larch (Larix olgensis) seedlings were soaked for 6 hours at the TMS concentrations of 2000, 1000, 500, 250, 125, and 62 μL·L?1. Mean seedling height, root collar diameter, ...The roots of 200 one-year-old Changbai Larch (Larix olgensis) seedlings were soaked for 6 hours at the TMS concentrations of 2000, 1000, 500, 250, 125, and 62 μL·L?1. Mean seedling height, root collar diameter, main root length and number of lateral roots were measured every 15 days during growing season from May 30 to Oct. 20. Experimental results showed that TMS treatments greatly promoted seedling growth and improved seedling quality. The treatment by 500 μL·L?1 TMS produced the best result, for which the mean height, root collar diameter, main root length, and the number of lateral roots of seedlings were increased by 42.5%, 30.7%, 14.0%, and 31.6%, respectively, compared to that of the control seedlings. As to seedling quality, grade-I seedling and grade-II seedlings were fifty-fifty, and no grade-III seedlings was found. The treatment by 500 μL·L?1 TMS resulted in the highest chlorophyll concentration. Keywords Changbai Larch - Larix olgensis - Seedling production - Nanostructured silicon dioxide CLC number S143.8 Document code B Foundation item: This study is supported by Jilin Forestry Group Co.Biography: LIN Baoshan (1955-), male, Associate professor at the college of forestry, Beihua University, Jilin City 132011, Jilin Province, P.R China.Responsible editor: Chai Ruihai.展开更多
Artemisinin（ART） is a widely used active drug for malaria, including severe and cerebral malaria. However, its therapeutic efficacy is affected by its lower bioavailability. In the present study, nanostructured lipi...Artemisinin（ART） is a widely used active drug for malaria, including severe and cerebral malaria. However, its therapeutic efficacy is affected by its lower bioavailability. In the present study, nanostructured lipid carriers（NLCs） were proposed as carrier of ART to improve pharmacokinetic properties of the drug. ART-NLC was prepared by high-pressure homogenization based on orthogonal design. The particle size, zeta potential, encapsulation efficiency（EE） and percentage of drug loading（DL） of ART-NLC were（53.06±2.11） nm,（–28.7±3.59） m V, 73.9%±0.5% and 11.23%±0.37%, respectively. ART-NLC showed the sustained release characteristics and scarcely the hemolysis effect on human red blood cells. The pharmacokinetics of ART-NLC for rats after tail intravenous injection（i.v） or intraperitoneal injection（i.p） were investigated by liquid chromatography-tandem mass spectroscopy（LC-MS/MS）. And ART solution was designed as control preparation. For rats of i.v groups, the AUC0–∞（（707.45±145.65） ng·h/m L） of ART-NLC were significantly bigger than that of ART（（368.98±139.58） ng·h/m L）. The MRT（（3.38±0.46） h） of ART-NLC was longer than that of ART（（1.39±0.61） h）. And similar results were observed for rats of i.p groups. The AUC0–∞（（1233.06±235.57） ng·h/m L） and MRT（（4.97±0.69） h） of ART-NLC were both bigger than those of ART, which were（871.17±234.03） ng·h/m L） and（1.75±0.31） h）, respectively. Compared with ART, ART-NLC showed a significant increase in AUC0–∞（P〈0.05） and MRT（P〈0.001） for both i.p and tail i.v administrations.展开更多
Bearings are the most important component of nearly all mechanical equipment, as they guarantee the steady running of the equipment, which is especially important for high-end equipment such as highspeed trains and sh...Bearings are the most important component of nearly all mechanical equipment, as they guarantee the steady running of the equipment, which is especially important for high-end equipment such as highspeed trains and shield tunneling machines. Requirements regarding the quality of bearings are increasing with the rapid development in technology. A country’s bearings manufacturing level directly reflects the level of that country’s steel metallurgy and machinery manufacturing. The performance of the bearing steel is the critical factor that determines the quality of a bearing. The development of new bearing steel with higher performance is the ambition of material researchers and the expectation of the manufacturing industry. Many famous bearing manufacturing enterprises are competing to develop the new generation of bearing steel. Nanostructured bainitic bearing steel (NBBS), which is a newly developed bearing steel, not only possesses high strength and toughness, but also exhibits excellent wear resistance and rolling contact fatigue (RCF) resistance. In recent years, relevant achievements in NBBS in China have led to significant progress in this field. NBBS was first used in China to manufacture large bearings for wind turbines and heavy-duty bearings, with excellent performance. As a result, NBBS and its corresponding heat-treatment process have been included in the national and industry standards for the first time. The bearing industry considers the exploitation of NBBS to be epoch-making, and has termed this kind of bearing as the second generation of bainitic bearing. In this paper, the development of NBBS is reviewed in detail, including its advantages and disadvantages. Further research directions for NBBS are also proposed.展开更多
Surface modification may have important influences on the penetration behavior of nanoscale drug delivery system. In the present study, we mainly focused on whether cell targeting or cell penetration could affect pene...Surface modification may have important influences on the penetration behavior of nanoscale drug delivery system. In the present study, we mainly focused on whether cell targeting or cell penetration could affect penetration abilities of nanostructured lipid carriers（NLC）. Real--time penetration of folate--or cell penetrating peptide（CPP）-modified NLC was evaluated using a multicellular tumor spheroid（MTS） established by stacking culture method as an in vitro testing platform. The results suggested that CPP modification had a better penetration behavior both on penetration depth and intensity compared with folate-modified NLC at the early stage of penetration process.展开更多
Visible-light-responsive ternary metal tungstate(MWO_4) photocatalysts are being increasingly investigated for energy conversion and environmental purification applications owing to their striking features, including ...Visible-light-responsive ternary metal tungstate(MWO_4) photocatalysts are being increasingly investigated for energy conversion and environmental purification applications owing to their striking features, including low cost,eco-friendliness, and high stability under acidic and oxidative conditions. However, rapid recombination of photoinduced electron–hole pairs and a narrow light response range to the solar spectrum lead to low photocatalytic activity of MWO_4-based materials, thus significantly hampering their wide usage in practice. To enable their widespread practical usage, significant efforts have been devoted, by developing new concepts and innovative strategies. In this review, we aim to provide an integrated overview of the fundamentals and recent progress of MWO_4-based photocatalysts. Furthermore, different strategies, including morphological control, surface modification, heteroatom doping, and heterojunction fabrication, which are employed to promote the photocatalyticactivities of MWO_4-based materials, are systematically summarized and discussed. Finally, existing challenges and a future perspective are also provided to shed light on the development of highly efficient MWO_4-based photocatalysts.展开更多
The microstructure and wear performance of M203-13% TiO2 coatings prepared by plasma spraying of agglom- erated nanoparticle powders were investigated. SEM analysis showed that the as-sprayed Al2O3-TiO2 coatings compr...The microstructure and wear performance of M203-13% TiO2 coatings prepared by plasma spraying of agglom- erated nanoparticle powders were investigated. SEM analysis showed that the as-sprayed Al2O3-TiO2 coatings comprise of two kinds of typical region： fully melted region and unmelted/partially melted nanostructured region, which is different than the conventional coating with lamellar structure. It is shown that the microhardness of the nanostructured coatings was about 15%-30% higher than that of the conventional coating and the wear resistance is significantly improved, especially under a high wear load. The nanostructured coating sprayed at a lower power shows a lower wear resistance than the coatings produced at a higher power, because of the presence of pores and microstructural defects which are detrimental to the fracture toughness of the coatings.展开更多
Electrochemiluminescence(ECL) is a kind of luminescent phenomenon caused by electrochemical reactions. Based on the advantages of ECL including low background, high sensitivity, strong spatiotemporal controllability a...Electrochemiluminescence(ECL) is a kind of luminescent phenomenon caused by electrochemical reactions. Based on the advantages of ECL including low background, high sensitivity, strong spatiotemporal controllability and simple operation, ECL imaging is able to visualize the ECL process,which can additionally achieve high throughput, fast and visual analysis. With the development of optical imaging technique, ECL imaging at micro-or nanoscale has been successfully applied in immunoassay,cell imaging, biochemical analysis, single-nanoparticle detection and study of mechanisms and kinetics of reactions, which has attracted extensive attention. In this review, the basic principles and apparatus of ECL imaging were briefly introduced at first. Then several latest and representative applications of ECL imaging based on nanomaterials and micro-/nanostructures were overviewed. Finally, the superiorities and challenges in ECL imaging for further development were discussed.展开更多
A nanostructured thermal barrier coating is prepared by air plasma spraying using the 8wt% Y_2O_3 partially stabilized zirconia nano-powder with an average grain size of 40 nm. The microstructure and phase composition...A nanostructured thermal barrier coating is prepared by air plasma spraying using the 8wt% Y_2O_3 partially stabilized zirconia nano-powder with an average grain size of 40 nm. The microstructure and phase composition of feedstock nano-powder and coating are investigated using SEM, TEM and XRD. It is found that the as-sprayed zirconia coating has an average grain size of 67 nm and mainly consistes of metastable tetragonal phase, together with some monoclinic phase and tetragonal phase. Thermal treatment results show that the grains of the nanostructured coating grow slightly below 900℃, whereas over 1000℃ the gains grow rapidly and monoclinic phase noticeably appeares.展开更多
基金supported by the National Research Foundation (NRF) of Korea funded by the Ministry of Science and ICT and Future Planning (MSIP) (2016R1E1A1A01943131)
文摘The intensive development of micro-/nanotechnologies offers a new route to construct sophisticated architectures of emerging soft electronics.Among the many classes of stretchable materials,micro-/nanostructured poly(dimethylsiloxane)(PDMS)has emerged as a vital building block based on its merits of flexibility,stretchability,simple processing,and,more importantly,high degrees of freedom of incorporation with other functional materials,including metals and semiconductors.The artificially designed geometries play important roles in achieving the desired mechanical and electrical performances of devices and thus show great potential for applications in the fields of stretchable displays,sensors and actuators as well as in health-monitoring device platforms.Meanwhile,novel lithographic methods to produce stretchable platforms with superb reliability have recently attracted research interest.The aim of this review is to comprehensively summarize the progress regarding micro-/nanostructured PDMS and their promising soft electronic applications.This review is concluded with a brief outlook and further research directions.
基金Project supported by China Postdoctoral Science Foundation(Grant No.2016M590137)the National Natural Science Foundation of China(Grant No.21476246)+2 种基金the Youth Innovation Promotion Association of the Chinese Academy of Sciences(Grant No.2016047)the KIST Institutional Program(Grant No.2E26291)Research Grants of NRF funded by the National Research Foundation under the Ministry of Science,ICT & Future,Korea(Grant No.NRF-2015H1D3A1036078)
文摘The research of superhydrophobic materials has attracted many researchers＇ attention due to its application value and prospects.In order to expand the serviceable range,people have investigated various superhydrophobic materials.The simple and easy preparation method has become the focus for superhydrophobic materials.In this paper,we present a program for preparing a rough surface on an aluminum foil,which possesses excellent hydrophobic properties after the treatment with low surface energy materials at high vacuum.The resulting contact angle is larger than 160° and the droplet cannot freeze on the surface above-10 ℃.Meanwhile,the modified aluminum foil with the thickness of less than 100 μm can be used as an ideal flexible applied material for superhydrophobicity/anti-icing.
基金The financial supports by the Chinese Academy of Sciences(Nos.XDC04030300 and XDB0510303)CAS-HK Joint Laboratory of Nanomaterials and MechanicsShenyang National Laboratory for Materials Science are acknowledged.
文摘Rolling contact fatigue performance is among the most important issues for applications of bearing steels.In this work,a recently developed surface modification technique,surface mechanical rolling treatment,was applied on a rare-earth addition bearing steel.And rolling contact fatigue behavior of treated samples was compared with that of as-received counterparts at different contacting stresses.The results demonstrated that a 700μm-thick gradient nanostructured surface layer is produced on samples by surface mechanical rolling treatment.The grain size decreases while the microhardness increases gradually with decreasing depth,reaching~23 nm and~10.2 GPa,respectively,at the top surface.Consequently,the rolling contact fatigue property is significantly enhanced.The characteristic life of treated samples is~3.2 times that of untreated counterparts according to Weibull curves at 5.6 GPa.Analyses of fatigue mechanisms demonstrated that the gradient nanostructured surface layer might not only retard material degradation and microcrack formation,but also prolong the steady-state elastic response stage under rolling contact fatigue.
基金supported by the National Nature Science Foundation of China(NSFC)(Grant No.11974033)Xuqiang Liu acknowledges support from the National Postdoctoral Foundation Project of China under Grant No.GZC20230215+2 种基金the National Nature Science Foundation of China under Grants No.12404001The XRD measurements at room and high temperatures were performed at the 4W2 HPStation of the Beijing Synchrotron Radiation Facility(BSRF)and beamline 15U1 of the Shanghai Synchrotron Radiation Facility(SSRF)In situ high-pressure,low-temperature XRD measurements were conducted at sector 16 ID-B,HPCAT of the Advanced Photon Source,and were supported by DOE-NNSA under Award No.DE-NA0001974.
文摘High-pressure β-Sn germanium may transform into diverse metastable allotropes with distinctive nanostructures and unique physical properties via multiple pathways under decompression.However,the mechanism and transition kinetics remain poorly understood.Here,we investigate the formation of metastable phases and nanostructures in germanium via controllable transition pathways of β-Sn Ge under rapid decompression at different rates.High-resolution transmission electron microscopy reveals three distinct metastable phases with the distinctive nanostructures:an almost perfect st12 Ge crystal,nanosized bc8/r8 structures with amorphous boundaries,and amorphous Ge with nanosized clusters (0.8–2.5 nm).Fast in situ x-ray diffraction and x-ray absorption measurements indicate that these nanostructured products form in certain pressure regions via distinct kinetic pathways and are strongly correlated with nucleation rates and electronic transitions mediated by compression rate,temperature,and stress.This work provides deep insight into the controllable synthesis of metastable materials with unique crystal symmetries and nanostructures for potential applications.
基金The authors thank the DFG(KI 2169/2-1)the European Union(EU-RIA NOMAD,101091669)for funding this work+1 种基金The Micro and Nanoanalytics Facility(MNaF),funded by the DFG(DFG INST 221/131-1)at the University of Siegen,and the Materials Science Faculty of the Isfahan University of Technology(IUT)were utilized for some of the work and analysis,respectively.
文摘This study introduces a nanostructured MgO coating fabricated via anodization in a non-aqueous electrolyte,offering a novel approach to addressing the challenges of corrosion resistance and biofunctionality.The surface was characterized before and after immersion testing using field emission scanning electron microscopy(FESEM),energy-dispersive X-ray spectroscopy(EDX),and X-ray diffraction(XRD).Electrochemical impedance spectroscopy(EIS)and potentiodynamic polarization tests demonstrated a 2-fold reduction in the corrosion resistance compared to untreated magnesium.Biomineralization studies demonstrated the uniform formation of apatite with a Ca/P ratio of 1.35 on the nanostructured surface after 14 days in simulated body fluid(SBF),surpassing that of microstructured MgO.Hydrogen evolution decreased from 912±38μL cm^(-2)for untreated Mg to 615±32μL cm^(-2)for the Mg/MgO nanostructure and 545±29μL cm^(-2)for the Mg/Mg O/HA sample.These findings highlight the potential of nanostructured MgO coatings to advance Mg-based implants by providing enhanced corrosion protection,improved biomineralization,reduced hemolysis and increased cell viability,and reduced H_(2)generation.
基金supported by the National Key R&D Program of China(No.2022YFB4002502)the National Natural Science Foundation of China(No.22279057)。
文摘Solid oxide cells(SOCs)are attractive electrochemical energy conversion/storage technologies for electricity/green hydrogen production because of the high efficiencies,all-solid structure,and superb reversibility.Nevertheless,the widespread applications of SOCs are remarkably restricted by the inferior stability and high material costs induced by the high operational temperatures(600-800℃).Tremendous research efforts have been devoted to suppressing the operating temperatures of SOCs to decrease the overall costs and enhance the long-term durability.However,fuel electrodes as key components in SOCs suffer from insufficient(electro)catalytic activity and inferior impurity tolerance/redox resistance at reduced temperatures.Nanostructures and relevant nanomaterials exhibit great potential to boost the performance of fuel electrodes for low-temperature(LT)-SOCs due to the unique surface/interface properties,enlarged active sites,and strong interaction.Herein,an in-time review about advances in the design and fabrication of nanostructured fuel electrodes for LT-SOCs is presented by emphasizing the crucial role of nanostructure construction in boosting the performance of fuel electrodes and the relevant/distinct material design strategies.The main achievements,remaining challenges,and research trends about the development of nanostructured fuel electrodes in LT-SOCs are also presented,aiming to offer important insights for the future development of energy storage/conversion technologies.
基金supported by the National Natural Science Foundation of China(Nos.52371063 and 52072110)the Natural Science Foundation of Hebei Province(No.E2018202034)+1 种基金the Central Funds Guiding the Local Science and Technology Development of Hebei Province(No.236Z7610G)the Graduate Innovation Project of Hebei Province(No.CXZZBS2022035).
文摘High porosity and high brittleness are the main reasons that limit the long-term service life of the alumina-titanium oxide composite coating.Herein,a metastable nanostructured aluminatitanium oxide composite coating with high density and high properties was synthesized by plasma spraying of TiO_(2)-Al composite powder.The main phases of the metastable nanostructured alumina-titanium oxide wereγ-Al_(2)O_(3),TiO and AlTiO_(2).The coating,as prepared,contains various metastable microstructures,such as fine-grained,intra-/inter-granular,and"self-locking"microstructures.These metastable microstruc-tures are important for the improvement of hardness and toughness of the coating.Compared with other alumina-based composite coatings,the metastable nanostructured aluminatitanium oxide composite coating showed the most impressive overall performance.The reinforcing and toughening mechanism of the metastable alumina-titanium oxide composite coating included fine grain strengthening and self-toughening of the metastable microstructure.
基金funding from the Australian Research Council(ARC Discovery Project,Nos.DP200101408 and DP230100183).
文摘1.Introduction The synthesis of bulk nanostructured multiphase(NM)mate-rials with extreme properties such as high hardness and strength is one of the most interesting research topics in materials science and engineering[1].At present,NM alloys can be produced by several synthesis methods,including sintering of nanocomposites[2,3],physical or chemical vapour deposition(PVD or CVD)[4],crystallization of metallic glasses[5],and severe plastic deforma-tion(SPD)[6-8].However,industry applications of bulk NM alloys produced by these methods are significantly restricted by their ge-ometrical and size limitations.Thus,the fabrication of large-scale NM alloys remains challenging.
基金the National Natural Science Foundation of China(82573571)the Shanghai 2025 Basic Research Plan Natural Science Foundation(25ZR1401393)the First Batch of Open Topics of the Shanghai Key Laboratory of Nautical Medicine and Translation of Drugs and Medical Devices(2025QN13)。
文摘The global burden of bacterial infections,exacerbated by antimicrobial resistance(AMR),necessitates innovative strategies.Bacterial protein vaccines offer promise by eliciting targeted immunity while circumventing AMR.However,their clinical translation is hindered by their inherently low immunogenicity,often requiring potent adjuvants and advanced delivery systems.Biomembrane nanostructures(e.g.,liposomes,exosomes,and cell membrane-derived nanostructures),characterized by superior biocompatibility,intrinsic targeting ability,and immune-modulating properties,could serve as versatile platforms that potentiate vaccine efficacy by increasing antigen stability,enabling codelivery of immunostimulants,and facilitating targeted delivery to lymphoid tissues/antigen-presenting cells.This intrinsic immunomodulation promotes robust humoral and cellular immune responses to combat bacteria.This review critically reviews(1)key biomembrane nanostructure classes for bacterial protein antigens,(2)design strategies leveraging biomembrane nanostructures to enhance humoral and cellular immune responses,(3)preclinical efficacy against diverse pathogens,and(4)translational challenges and prospects.Biomembrane nanostructure-driven approaches represent a paradigm shift in the development of next-generation bacterial protein vaccines against resistant infections.
基金Project(514120203) supported by the Advanced Investigation Foundation of Weapon Equipment
文摘The extrusion of Al-Si alloy powders with different particle sizes allows manufacture of different products with unique microstructures and therefore with unique mechanical properties. The effects of powder size on the extrusion behavior and process defect of Al-18%Si alloy were studied by means of microscopy (optical, scanning electron) and density determination. The main objective of the work is to demonstrate the influence of the powder material characteristics on final density and quality of bar. The results show that the bigger the powder particles, the better the performance of cold compacting. The surface of alloy bar extruded from big particles has good quality without cracking. While the smaller the powder particles, the higher the density and the better the microstructure and mechanical properties. For practice application, the mixed powders are better than single powder.
基金funding from SFB 1415 subproject B04(Deutsche Forschungsgemeinschaft,No.417590517)supported by the Deutsche Forschungsgemeinschaft through the Würzburg-Dresden Cluster of Excellence on Complexity and Topology in Quantum Matter-ct.qmat(EXC 2147,No.390858490)the support provided by the DRESDEN-concept alliance of research institutions.
文摘Twisted multilayers of two-dimensional materials attract widespread research interest due to their intriguing electronic and optical properties related to their chiral symmetry breaking and moiréeffects.The two-dimensional transition metal dichalcogenide MoSe_(2) is a particularly promising material for twisted multilayers,capable of sustaining moiréexcitons.Here,we report on a rational bottomup synthesis approach for twisted MoSe_(2) flakes by chemical vapor transport(CVT).Screw dislocation-driven growth was forced by surface-fused SiO_(2)nanoparticles on the substrates that serve as potential nucleation points in low supersaturation condition.Thus,crystal growth by in-situ CVT under addition of MoCl_(5) leads to bulk 2H-MoSe_(2) in a temperature gradient from 900 to 820℃ with a dwell time of 96 h.Hexagonally shaped 2H-MoSe_(2) flakes were grown from 710 to 685℃ with a dwell time of 30 min on SiO_(2)@Al_(2)O_(3)(0001)substrates.Electron backscatter diffraction as well as electron microscopy reveals the screw dislocation-driven growth of triangular 3R-MoSe_(2) with individual step heights between 0.9 and 2.9 nm on SiO_(2)@Si(100)under the same conditions.Finally,twisted MoSe_(2) flakes exhibiting a twist angle of 19°with respect to the[010]zone axis could be synthesized.
文摘The Ni-based alloy composite coatings reinforced by nanostructured Al2O3-40%TiO2 multiphase ceramic particles were prepared on the surface of 7005 aluminum alloy by plasma spray technology. The microstructure and tribological properties of the composite coatings were researched. The results show that the composite coatings mainly consist of γ-Ni, α-Al2O3, γ-Al2O3 and rutile-TiO2 etc, and exhibit lower friction coefficients and wear losses than the Ni-based alloy coatings at different loads and speeds. The composite coating bears low contact stress at 3 N and its wear mechanism is micro-cutting wear. As loads increase to 6-12 N, the contact stress is higher than the elastic limit stress of worn surface, and the wear mechanisms change into multi-plastic deformation wear, micro-brittle fracture wear and abrasive wear. With the increase of speeds, the contact temperature of worn surface increases. The composite coating experiences multi-plastic deformation wear, fatigue wear and adhesive wear.
基金This study is supported by Jilin Forestry Group Co.
文摘The roots of 200 one-year-old Changbai Larch (Larix olgensis) seedlings were soaked for 6 hours at the TMS concentrations of 2000, 1000, 500, 250, 125, and 62 μL·L?1. Mean seedling height, root collar diameter, main root length and number of lateral roots were measured every 15 days during growing season from May 30 to Oct. 20. Experimental results showed that TMS treatments greatly promoted seedling growth and improved seedling quality. The treatment by 500 μL·L?1 TMS produced the best result, for which the mean height, root collar diameter, main root length, and the number of lateral roots of seedlings were increased by 42.5%, 30.7%, 14.0%, and 31.6%, respectively, compared to that of the control seedlings. As to seedling quality, grade-I seedling and grade-II seedlings were fifty-fifty, and no grade-III seedlings was found. The treatment by 500 μL·L?1 TMS resulted in the highest chlorophyll concentration. Keywords Changbai Larch - Larix olgensis - Seedling production - Nanostructured silicon dioxide CLC number S143.8 Document code B Foundation item: This study is supported by Jilin Forestry Group Co.Biography: LIN Baoshan (1955-), male, Associate professor at the college of forestry, Beihua University, Jilin City 132011, Jilin Province, P.R China.Responsible editor: Chai Ruihai.
基金National Natural Science Foundation of China(Grant No.81373364)The Subject clots Project Serving Pharmaceutical Industrial Innovation of Shanxi Province
文摘Artemisinin（ART） is a widely used active drug for malaria, including severe and cerebral malaria. However, its therapeutic efficacy is affected by its lower bioavailability. In the present study, nanostructured lipid carriers（NLCs） were proposed as carrier of ART to improve pharmacokinetic properties of the drug. ART-NLC was prepared by high-pressure homogenization based on orthogonal design. The particle size, zeta potential, encapsulation efficiency（EE） and percentage of drug loading（DL） of ART-NLC were（53.06±2.11） nm,（–28.7±3.59） m V, 73.9%±0.5% and 11.23%±0.37%, respectively. ART-NLC showed the sustained release characteristics and scarcely the hemolysis effect on human red blood cells. The pharmacokinetics of ART-NLC for rats after tail intravenous injection（i.v） or intraperitoneal injection（i.p） were investigated by liquid chromatography-tandem mass spectroscopy（LC-MS/MS）. And ART solution was designed as control preparation. For rats of i.v groups, the AUC0–∞（（707.45±145.65） ng·h/m L） of ART-NLC were significantly bigger than that of ART（（368.98±139.58） ng·h/m L）. The MRT（（3.38±0.46） h） of ART-NLC was longer than that of ART（（1.39±0.61） h）. And similar results were observed for rats of i.p groups. The AUC0–∞（（1233.06±235.57） ng·h/m L） and MRT（（4.97±0.69） h） of ART-NLC were both bigger than those of ART, which were（871.17±234.03） ng·h/m L） and（1.75±0.31） h）, respectively. Compared with ART, ART-NLC showed a significant increase in AUC0–∞（P〈0.05） and MRT（P〈0.001） for both i.p and tail i.v administrations.
基金the Natural Science Foundation of China (51831008 and 51471146)the National High Technology Research and Development Program of China (2012AA03A504)+2 种基金the National Science Foundation for Distinguished Young Scholars of China (50925522)the China Postdoctoral Science Foundation (2018M631762)the Youth Talent Projects of Colleges in Hebei Province (BJ2018056).
文摘Bearings are the most important component of nearly all mechanical equipment, as they guarantee the steady running of the equipment, which is especially important for high-end equipment such as highspeed trains and shield tunneling machines. Requirements regarding the quality of bearings are increasing with the rapid development in technology. A country’s bearings manufacturing level directly reflects the level of that country’s steel metallurgy and machinery manufacturing. The performance of the bearing steel is the critical factor that determines the quality of a bearing. The development of new bearing steel with higher performance is the ambition of material researchers and the expectation of the manufacturing industry. Many famous bearing manufacturing enterprises are competing to develop the new generation of bearing steel. Nanostructured bainitic bearing steel (NBBS), which is a newly developed bearing steel, not only possesses high strength and toughness, but also exhibits excellent wear resistance and rolling contact fatigue (RCF) resistance. In recent years, relevant achievements in NBBS in China have led to significant progress in this field. NBBS was first used in China to manufacture large bearings for wind turbines and heavy-duty bearings, with excellent performance. As a result, NBBS and its corresponding heat-treatment process have been included in the national and industry standards for the first time. The bearing industry considers the exploitation of NBBS to be epoch-making, and has termed this kind of bearing as the second generation of bainitic bearing. In this paper, the development of NBBS is reviewed in detail, including its advantages and disadvantages. Further research directions for NBBS are also proposed.
基金National key Basic Research Program(Grant No.2013CB932501)National Natural Science Foundation of China(Grant No.81273454 and 81473156)+1 种基金Beijing National Science Foundation(Grant No.7132113)Doctoral Foundation of the Ministry of Education(Grant No.20130001110055)
文摘Surface modification may have important influences on the penetration behavior of nanoscale drug delivery system. In the present study, we mainly focused on whether cell targeting or cell penetration could affect penetration abilities of nanostructured lipid carriers（NLC）. Real--time penetration of folate--or cell penetrating peptide（CPP）-modified NLC was evaluated using a multicellular tumor spheroid（MTS） established by stacking culture method as an in vitro testing platform. The results suggested that CPP modification had a better penetration behavior both on penetration depth and intensity compared with folate-modified NLC at the early stage of penetration process.
基金support of NSFC 51702284Fundamental Research Funds for the Central Universities (112109*172210171)+2 种基金the Startup Foundation for Hundred-Talent Program of Zhejiang University (112100-193820101/001/022)support of the NSFC 21501138the Science Research Foundation of Wuhan Institute of Technology (K201513)
文摘Visible-light-responsive ternary metal tungstate(MWO_4) photocatalysts are being increasingly investigated for energy conversion and environmental purification applications owing to their striking features, including low cost,eco-friendliness, and high stability under acidic and oxidative conditions. However, rapid recombination of photoinduced electron–hole pairs and a narrow light response range to the solar spectrum lead to low photocatalytic activity of MWO_4-based materials, thus significantly hampering their wide usage in practice. To enable their widespread practical usage, significant efforts have been devoted, by developing new concepts and innovative strategies. In this review, we aim to provide an integrated overview of the fundamentals and recent progress of MWO_4-based photocatalysts. Furthermore, different strategies, including morphological control, surface modification, heteroatom doping, and heterojunction fabrication, which are employed to promote the photocatalyticactivities of MWO_4-based materials, are systematically summarized and discussed. Finally, existing challenges and a future perspective are also provided to shed light on the development of highly efficient MWO_4-based photocatalysts.
文摘The microstructure and wear performance of M203-13% TiO2 coatings prepared by plasma spraying of agglom- erated nanoparticle powders were investigated. SEM analysis showed that the as-sprayed Al2O3-TiO2 coatings comprise of two kinds of typical region： fully melted region and unmelted/partially melted nanostructured region, which is different than the conventional coating with lamellar structure. It is shown that the microhardness of the nanostructured coatings was about 15%-30% higher than that of the conventional coating and the wear resistance is significantly improved, especially under a high wear load. The nanostructured coating sprayed at a lower power shows a lower wear resistance than the coatings produced at a higher power, because of the presence of pores and microstructural defects which are detrimental to the fracture toughness of the coatings.
基金supported by the National Natural Science Foundation of China (Nos. 21575126 and 21874117)the Natural Science Foundation of Zhejiang Province (No. LZ18B050001)
文摘Electrochemiluminescence(ECL) is a kind of luminescent phenomenon caused by electrochemical reactions. Based on the advantages of ECL including low background, high sensitivity, strong spatiotemporal controllability and simple operation, ECL imaging is able to visualize the ECL process,which can additionally achieve high throughput, fast and visual analysis. With the development of optical imaging technique, ECL imaging at micro-or nanoscale has been successfully applied in immunoassay,cell imaging, biochemical analysis, single-nanoparticle detection and study of mechanisms and kinetics of reactions, which has attracted extensive attention. In this review, the basic principles and apparatus of ECL imaging were briefly introduced at first. Then several latest and representative applications of ECL imaging based on nanomaterials and micro-/nanostructures were overviewed. Finally, the superiorities and challenges in ECL imaging for further development were discussed.
文摘A nanostructured thermal barrier coating is prepared by air plasma spraying using the 8wt% Y_2O_3 partially stabilized zirconia nano-powder with an average grain size of 40 nm. The microstructure and phase composition of feedstock nano-powder and coating are investigated using SEM, TEM and XRD. It is found that the as-sprayed zirconia coating has an average grain size of 67 nm and mainly consistes of metastable tetragonal phase, together with some monoclinic phase and tetragonal phase. Thermal treatment results show that the grains of the nanostructured coating grow slightly below 900℃, whereas over 1000℃ the gains grow rapidly and monoclinic phase noticeably appeares.
