The cultivation of top-notch innovative talents is one of the most prominent tasks in China s universities in the new era,and also an opportunity and challenge for local universities.Taking the food subject of local u...The cultivation of top-notch innovative talents is one of the most prominent tasks in China s universities in the new era,and also an opportunity and challenge for local universities.Taking the food subject of local universities as an example,some suggestions were put forward from the aspects of security measures,teacher team construction,talent selection and management,and talent cultivation,in order to provide reference for the exploration and practice of cultivating top-notch innovative talents in the food subject of local universities.展开更多
Osteoarthritis(OA) causes the destruction of joints. Its pathogenesis is still under investigation, and there is no effective diseasemodifying therapy. Here, we report that elevated cyclooxygenase-2(COX-2) expression ...Osteoarthritis(OA) causes the destruction of joints. Its pathogenesis is still under investigation, and there is no effective diseasemodifying therapy. Here, we report that elevated cyclooxygenase-2(COX-2) expression in the osteocytes of subchondral bone causes both spontaneous OA and rheumatoid arthritis(RA). The knockout of COX-2 in osteocytes or treatment with a COX-2 inhibitor effectively rescues the structure of subchondral bone and attenuates cartilage degeneration in spontaneous OA(STR/Ort)mice and tumor necrosis factor-α transgenic RA mice. Thus, elevated COX-2 expression in subchondral bone induces both OAassociated and RA-associated joint cartilage degeneration. The inhibition of COX-2 expression can potentially modify joint destruction in patients with arthritis.展开更多
Nine years(2001–2009)of data from the Cluster spacecraft are analyzed in this study of the Earth’s mid-and high-altitude(2–9RE)cusp.Properties of the cusp region,and its location and size in the Solar Magnetic coor...Nine years(2001–2009)of data from the Cluster spacecraft are analyzed in this study of the Earth’s mid-and high-altitude(2–9RE)cusp.Properties of the cusp region,and its location and size in the Solar Magnetic coordinate system,are studied statistically.The survey shows that(1)the relationships between X and Z are nearly linear for the poleward,equatorward boundaries and the center of the cusp;(2)the relationship between cusp width in the X direction and Z can be expressed by a quadratic function;(3)the cusp region is almost dawn-dusk symmetric for the cusp width in the X direction.Based on topology information,a new normalized statistical methodology is developed to organize the measurements of cusp crossings to obtain distributions of magnetic field and plasma parameters in the XZ plane.The statistical results show that(1)Bx is mostly negative and Bz is always negative;(2)proton velocity is found to be positive for Vx and Vz at low altitudes,while Vx and Vz are negative on the equator side and negative Vx and positive Vz on the pole side at high altitudes;(3)proton density is higher on the equator side than on the pole side.Results reported here will be useful in suggesting directions for future cusp research.展开更多
Two THEMIS(Time History of Events and Macroscale Interactions during Substorms)spacecraft,B and C,began orbiting the Moon in 2011 and have since provided routine measurements of the plasma conditions in the lunar orbi...Two THEMIS(Time History of Events and Macroscale Interactions during Substorms)spacecraft,B and C,began orbiting the Moon in 2011 and have since provided routine measurements of the plasma conditions in the lunar orbit.In this study,we systematically compare these measurements in near-Earth space with solar wind measurements obtained from the Lagrangian 1(L1)point and propagated to the Earth,including measurements in the OMNI database and from the Wind spacecraft.A statistical comparison between THEMIS data and data from the OMNI database from September 2011 to December 2017 showed that the Y and Z components of the magnetic field and the flow speed are generally consistent between the two data sets.The ion number density and the dynamic pressure measured by THEMIS in near-Earth space are lower than those in the OMNI database,suggesting possible variation in the solar wind environment while propagating from the L1 point to near-Earth space.We further show two examples in which near-Earth solar wind measurements are applied in calculating the magnetopause location and in quantifying the magnetic field response to interplanetary shocks.Both examples suggest that using solar wind data from near-Earth space achieves better results than using solar wind data from the L1 point.These results provide validation of THEMIS-B and THEMIS-C as an alternative monitor of the near-Earth solar wind environment.展开更多
A continuous hot embossing method is reported in this paper. The continuous means that the extruder and the hot embossing equipment is used in series, the polymer film is embossed after extrusion immediately. The basi...A continuous hot embossing method is reported in this paper. The continuous means that the extruder and the hot embossing equipment is used in series, the polymer film is embossed after extrusion immediately. The basic principle of this method, the key design point and the corresponding operate process of the embossing equipment is described in this paper. The polymer diffuser with micro-lens matrix on its surface is designed and the optical properties are simulated. Then, the diffuser is fabricated by the embossing equipment. The optical properties of the diffuser are tested and compared with the results of the simulation to verify the reproducibility of the equipment. By this method, the diffuser with large area can be fabricated with high precision of graphic replication, high efficiency and low cost.展开更多
The notorious dendrite and infinite volume change seriously restrict the advancement of lithium metal anodes(LMAs),during the long-term process of stripping/plating.Herein,the nanosheets of metal fluoride(CoF_(2))and ...The notorious dendrite and infinite volume change seriously restrict the advancement of lithium metal anodes(LMAs),during the long-term process of stripping/plating.Herein,the nanosheets of metal fluoride(CoF_(2))and metal nitride(CoN)with magnificent lithiophilicity on the nickel(Ni)foam are designed as the“regulator”to uniform the Li plating and build stronger solid electrolyte interface(SEI)layer for dendrite free LMAs.The Ni foam offers abundant space to receive deposited Li metal.The CoN nanosheets can guarantee the fast transfer of electrons,which provides a stable interface of Li^(+)reduction.Moreover,the nanosheet structure with lithiophilicity would accelerate the move of Li+and decrease the nucleation barrier,due to the high lattice-matching of Li and CoN.Meanwhile,the CoF_(2) could increase the content of F(LiF)in the SEI layer,which enhances the strength and avoids the destruction of SEI layer.With the cooperation of CoN and CoF_(2),the composited anode(Li/NF@CNCF)exhibits ultra-long cycle performance(more than 1200 h)and fantastic structure stability at 1 mA·cm^(-2) with 1 mAh·cm^(-2).Based on the LiFePO_(4) and Li/NF@CNCF,the full cells deliver excellent specifical capacity and steady coulombic efficiency.The strategy contributes an effective approach to alleviate the issues of lithium metal anodes in the field of LMAs.展开更多
Mantle peridotite xenoliths in Jiaohe City,located near the northern part of the Tan-Lu fault,are key evidence for constraining the nature and evolution of the subcontinental lithospheric mantle(SCLM)of the NE China.G...Mantle peridotite xenoliths in Jiaohe City,located near the northern part of the Tan-Lu fault,are key evidence for constraining the nature and evolution of the subcontinental lithospheric mantle(SCLM)of the NE China.Geochemical characteristics of Jiaohe peridotite xenoliths have been well studied,whereas the microstructures and associated fabrics remain poorly known.We report here major element composition of the constituent minerals,P-T conditions,microstructure,lattice preferred orientations(LPOs)of a set of xenoliths having coarse-grained and granuloblastic to porphyroclastic textures.These xenoliths are characterized by forsterite content of 89-91 in olivine.Dislocation microstructures,in olivine crystals revealed by oxidation decoration technique,are characterized by free dislocation,dislocation walls,dislocation loops and subgrains.Microstructures and deformation mechanism maps indicate that dislocation creep is the dominant deformation mechanism of almost anhydrous olivine in the SCLM.In most samples,the observed LPOs of olivine are typical A-type fabric.Stresses measured in the xenoliths using several olivine piezometers are~2.7-8.5 MPa.The equilibration temperature conditions,calculated using several geo-thermometers,indicate the equilibrium temperature condition of peridotites in a range of 891 to 993℃.These results provide rheological constraint on the deformation of the SCLM in Jiaohe.Combined with the data for mantle xenoliths from adjacent regions,a heterogeneous evolution of the lithosphere deformation is inferred at the Jiaohe region.We propose that characteristics of the studied peridotite may be related to the Tan-Lu fault.展开更多
We use a single-molecule self-assembled layer of an aromatic organophosphonic acid(2PACz) to modify the cathode interface layer in inverted organic solar cells(OSCs). The modified OSCs not only have an obvious improve...We use a single-molecule self-assembled layer of an aromatic organophosphonic acid(2PACz) to modify the cathode interface layer in inverted organic solar cells(OSCs). The modified OSCs not only have an obvious improvement in power conversion efficiency(PCE), but also demonstrate greatly enhanced air stability. Ultraviolet photoelectron spectroscopy shows that the work function of cathode interlayer after modification by 2PACz is more suitable for electron extraction. In addition, the surface energy is reduced without affecting the film deposition, which will be beneficial to reduce the interfacial traps. As a result,the PCE of OSCs based on the PBDB-T:IT-M system is increased, and its stability in air is greatly improved(remaining 88% of its initial PCE after 555 h in air). Therefore, we provide a new strategy for constructing high-performance non-fullerene OSCs with enhanced air stability.展开更多
Bi_(1-x)Tb_xFeO_3 thin films were prepared on SnO_2(fluorine doped tin oxide) substrates by a sol—gel method.The structural and electrical properties of the BiFeO_3 thin films were characterized and tested.The result...Bi_(1-x)Tb_xFeO_3 thin films were prepared on SnO_2(fluorine doped tin oxide) substrates by a sol—gel method.The structural and electrical properties of the BiFeO_3 thin films were characterized and tested.The results indicated that the diffraction peak of the Tb-doped BiFeO_3 films was shifted towards right as the doping amounts were increased.The structure was transformed from the rhombohedral to tetragonal/orthorhombic phase.The Bi_(0.89)Tb_(0.11)FeO_3 thin film showed the well-developed P—E loops,which enhanced remnant polarization(Pr = 88.05 μC/cm^2) at room temperature.The dielectric constant and dielectric loss of Bi_(0.89)Tb_(0.11)FeO_3 thin film at 100 kHz were 185 and 0.018,respectively.Furthermore,the Bi_(0.89)Tb_(0.11)FeO_3 thin film showed a relatively low leakage current density of 2.07 × 10^(-5) A/cm^2 at an applied electric field of 150 kV/cm.The Xray photoelectron spectroscopy(XPS) spectra indicated that the presence of Fe^(2+) ions in the Bi_(0.89)Tb_(0.11)FeO_3thin film was less than that in the pure BiFeO_3.展开更多
Recently,flexible oxide epitaxial thin films are of increasing interests owing to their excellent physical properties and wide applications.The oxide epitaxial thin films with flexible,lightweight and wearable are pro...Recently,flexible oxide epitaxial thin films are of increasing interests owing to their excellent physical properties and wide applications.The oxide epitaxial thin films with flexible,lightweight and wearable are promising for the applications in flexible and wearable devices,such as flexible sensors,flexible detectors,flexible oscillators,flexible spintronics,wearable displays and electronic skin,etc.This review aims to summarize the fabrication,physical properties and applications of the flexible oxide epitaxial thin films for wearable electronics in most recent few years.The fabrication of flexible oxide epitaxial thin films reviewed here mainly includes the deposition on flexible substrates at high temperature and epitaxial lift-off(ELO)from rigid substrates.The physical properties and applications of flexible oxide epitaxial thin films reviewed here chiefly focus on the area of electricity and magnetism,including stable and tunable physical properties in the flexible oxide epitaxial thin films.In final,the perspectives and challenges of flexible oxide thin films for wearable electronics have been also addressed.展开更多
Dielectrics used for energy storage are highly desired for power electronics and pulse power applications and the polymer capacitors are the main commercial ones available.The development of flexible electronics and w...Dielectrics used for energy storage are highly desired for power electronics and pulse power applications and the polymer capacitors are the main commercial ones available.The development of flexible electronics and wearable devices require the relative materials being flexible.Besides,high temperature resistance is also desired because of the rising demand for high power devices and large electricity under elevated temperature.The polymer dielectrics for polymer capacitors are flexible but with relatively low working temperature normally less than 100℃.Therefore,fabricating a dielectric material to satisfy the flexibility and high working temperature simultaneously is still a great challenge.Here we propose one solution by demonstrating a hand-exfoliated fluorophlogopite film with micrometer scale thickness.Among which,the mica film with a thickness of around 10μm(Mica-10)exhibits the inorganic-like temperature stability even polymer-like flexibility.From 25℃to 200℃,Mica-10 has an energy density of around 11.27 J/cm^(3)with a variation within 2%,accompanied by a charge-discharge efficiency of around 95%at an electric field of 500 MV/m.Meanwhile,the thin thickness makes Mica-10 flexible,enabling its excellent flexibility and durability.This work revives the traditional material,mica,providing a way for high-temperature energy storage applications.展开更多
There is a need for synthetic grafts to reconstruct large bone defects using minimal invasive surgery.Our previous study showed that incorporation of Sr into bioactive borate glass cement enhanced the osteogenic capac...There is a need for synthetic grafts to reconstruct large bone defects using minimal invasive surgery.Our previous study showed that incorporation of Sr into bioactive borate glass cement enhanced the osteogenic capacity in vivo.However,the amount of Sr in the cement to provide an optimal combination of physicochemical properties and capacity to stimulate bone regeneration and the underlying molecular mechanism of this stimulation is yet to be determined.In this study,bone cements composed of bioactive borosilicate glass particles substituted with varying amounts of Sr(0 mol%to 12 mol%SrO)were created and evaluated in vitro and in vivo.The setting time of the cement increased with Sr substitution of the glass.Upon immersion in PBS,the cement degraded and converted more slowly to HA(hydroxyapatite)with increasing Sr substitution.The released Sr2+modulated the proliferation,differentiation,and mineralization of hBMSCs(human bone marrow mesenchymal stem cells)in vitro.Osteogenic characteristics were optimally enhanced with cement(designated BG6Sr)composed of particles substituted with 6mol%SrO.When implanted in rabbit femoral condyle defects,BG6Sr cement supported better peri-implant bone formation and bone-implant contact,comparing to cements substituted with 0mol%or 9mol%SrO.The underlying mechanism is involved in the activation of Wnt/β-catenin signaling pathway in osteogenic differentiation of hBMSCs.These results indicate that BG6Sr cement has a promising combination of physicochemical properties and biological performance for minimally invasive healing of bone defects.展开更多
In osteoporosis scenario, tissue response to implants is greatly impaired by the deteriorated boneregeneration microenvironment. In the present study, a Mg-containing akermanite (Ak) ceramic wasemployed for the treatm...In osteoporosis scenario, tissue response to implants is greatly impaired by the deteriorated boneregeneration microenvironment. In the present study, a Mg-containing akermanite (Ak) ceramic wasemployed for the treatment of osteoporotic bone defect, based on the hypothesis that both beneficialions (e.g. Mg^2+ ect.) released by the implants and the weak alkaline microenvironment pH (μe-pH) itcreated may play distinct roles in recovering the abnormal bone regeneration by stimulating osteoblasticanabolic effects. The performance of Ak, b-tricalcium phosphate (β-TCP) and Hardystone (Har) in healinga 3 mm bone defect on the ovariectomized (OVX) osteoporotic rat model was evaluated. Our resultsindicated that, there's more new bone formed in Ak group than in β-TCP or Har group at week 9. Theinitial me-pHs of Ak were significantly higher than that of the β-TCP and Blank group, and this weakalkaline condition was maintained till at least 9 weeks post-surgery. Increased osteoblastic activity whichwas indicated by higher osteoid secretion was observed in Ak group at week 4 to week 9. An intermediatelayer which was rich in phosphorus minerals and bound directly to the new forming bone wasdeveloped on the surface of Ak. In a summary, our study demonstrates that Ak exhibits a superior boneregenerative performance under osteoporosis condition, and might be a promising candidate for thetreatment of osteoporotic bone defect and fracture.展开更多
Oxychalcogenides have been drawn much attention to be explored as nonlinear optical(NLO)materials in recent years.To date,all the NLO oxychalcogenides crystallize in low dimensional structures.Herein,a new oxysulfide ...Oxychalcogenides have been drawn much attention to be explored as nonlinear optical(NLO)materials in recent years.To date,all the NLO oxychalcogenides crystallize in low dimensional structures.Herein,a new oxysulfide K_(2)Ba_(0.5)Ga_(9)O_(2)S_(13) was obtained via three-dimensional(3D){[Ga_(9)O_(2)S_(13)]^(3-)}_(∞)polyanionic framework.As the first oxychalcogenide with 3D NLO-acitve polyanionic framework,K_(2)Ba_(0.5)Ga_(9)O_(2)S_(13) has a wide band gap of 3.72 eV,and exhibits a high laser-induced damage threshold(LIDT,17×AgGaS_(2)).It presents moderate phase-matchable NLO response of 0.5×AgGaS_(2) at 2.1μm and 2×KH_(2)PO_(4) at 1.064μm.The theoretical calculation results indicate that the NLO response is mainly contributed from[Ga(2)S4]unit-built[Ga(2)_(3)S_(10)]windmill-like motif.This work may stimulate the exploration of more NLO oxychalcogenides with balanced performances.展开更多
The effect of thermoacidophilic archaeon Metallosphaera cuprina(M.cuprina)on the corrosion of Q235 carbon steel in its culture medium was investigated in this work.In the sterile culture medium,the carbon steels showe...The effect of thermoacidophilic archaeon Metallosphaera cuprina(M.cuprina)on the corrosion of Q235 carbon steel in its culture medium was investigated in this work.In the sterile culture medium,the carbon steels showed uniform corrosion morphologies and almost no corrosion products covered the sample surface during 14 days of immersion test.In the presence of M.cuprina,some corrosion pits appeared on the surface of carbon steels in the immersion test,exhibiting typical localized corrosion morphologies.Moreover,the sample surfaces were covered by a large number of insoluble precipitates during the immersion.After 14 days,the thickness of precipitates reached approximately 50μm.The results of weight loss test and electrochemical test demonstrated that the carbon steels in the M.cuprina-inoculated culture medium had higher corrosion rate than that in the sterile culture medium.The oxygen concentration cell caused by M.cuprina biofilms resulted in localized corrosion behavior,and the ferrous oxidation ability of M.cuprina accelerated the anodic dissolution of carbon steels,thus promoting the corrosion process of carbon steels.展开更多
It is a challenge to reduce the dielectric loss and increase the tunability of pure barium strontium titanate(BST)films for microwave tunable application because these two properties change simultaneously.Herein,a nov...It is a challenge to reduce the dielectric loss and increase the tunability of pure barium strontium titanate(BST)films for microwave tunable application because these two properties change simultaneously.Herein,a novel composite of strontium titanate(ST)and potassium-doped BST(KBST)has been designed as ST/KBST/ST sandwich-type film with various ST and KBST layers.X-ray diffraction patterns show that the film exhibits cubic perovskite polycrystalline structure composed of BST and ST phase,mainly grow along(110)crystal plane with average grain size of less than 20 nm and decreasing BST phase/ST phase ratio with increasing film thickness.Scanning electron microscope shows that no interfacial layer can be observed,indicating that ST and KBST are fully compounded.Low dielectric loss and high tunability at-10-10 V and stable and excellent dielectric properties at 1 GHz are achieved,meeting the needs of microwave tunable application at high frequency.The surface structures are also studied by other analysis methods,and ST/MgBST/ST sandwich-type film is compared.展开更多
The authors regret that the printed version of the above article contained a number of errors which were not identified during the proofing stage.The correct and final version follows.The authors would like to apologi...The authors regret that the printed version of the above article contained a number of errors which were not identified during the proofing stage.The correct and final version follows.The authors would like to apologies for any inconvenience caused.The authors regret:1.“…and the underlying molecular mechanism of this simulation is yet to be determined”,Page 335,needs to be corrected to“and the underlying molecular mechanism of this stimulation is yet to be determined”.展开更多
基金Supported by the Education Reform Project of Chengdu University (cdjgb2022123).
文摘The cultivation of top-notch innovative talents is one of the most prominent tasks in China s universities in the new era,and also an opportunity and challenge for local universities.Taking the food subject of local universities as an example,some suggestions were put forward from the aspects of security measures,teacher team construction,talent selection and management,and talent cultivation,in order to provide reference for the exploration and practice of cultivating top-notch innovative talents in the food subject of local universities.
基金supported by the NIH/NIAMS grants AR071432 and AR063943 (to X.C.)
文摘Osteoarthritis(OA) causes the destruction of joints. Its pathogenesis is still under investigation, and there is no effective diseasemodifying therapy. Here, we report that elevated cyclooxygenase-2(COX-2) expression in the osteocytes of subchondral bone causes both spontaneous OA and rheumatoid arthritis(RA). The knockout of COX-2 in osteocytes or treatment with a COX-2 inhibitor effectively rescues the structure of subchondral bone and attenuates cartilage degeneration in spontaneous OA(STR/Ort)mice and tumor necrosis factor-α transgenic RA mice. Thus, elevated COX-2 expression in subchondral bone induces both OAassociated and RA-associated joint cartilage degeneration. The inhibition of COX-2 expression can potentially modify joint destruction in patients with arthritis.
基金the National Natural Science Foundation of China,grants 41821003,41974194 and 41574154.
文摘Nine years(2001–2009)of data from the Cluster spacecraft are analyzed in this study of the Earth’s mid-and high-altitude(2–9RE)cusp.Properties of the cusp region,and its location and size in the Solar Magnetic coordinate system,are studied statistically.The survey shows that(1)the relationships between X and Z are nearly linear for the poleward,equatorward boundaries and the center of the cusp;(2)the relationship between cusp width in the X direction and Z can be expressed by a quadratic function;(3)the cusp region is almost dawn-dusk symmetric for the cusp width in the X direction.Based on topology information,a new normalized statistical methodology is developed to organize the measurements of cusp crossings to obtain distributions of magnetic field and plasma parameters in the XZ plane.The statistical results show that(1)Bx is mostly negative and Bz is always negative;(2)proton velocity is found to be positive for Vx and Vz at low altitudes,while Vx and Vz are negative on the equator side and negative Vx and positive Vz on the pole side at high altitudes;(3)proton density is higher on the equator side than on the pole side.Results reported here will be useful in suggesting directions for future cusp research.
基金supported by the National Natural Science Foundation of China (grants 41821003 and 41974194)
文摘Two THEMIS(Time History of Events and Macroscale Interactions during Substorms)spacecraft,B and C,began orbiting the Moon in 2011 and have since provided routine measurements of the plasma conditions in the lunar orbit.In this study,we systematically compare these measurements in near-Earth space with solar wind measurements obtained from the Lagrangian 1(L1)point and propagated to the Earth,including measurements in the OMNI database and from the Wind spacecraft.A statistical comparison between THEMIS data and data from the OMNI database from September 2011 to December 2017 showed that the Y and Z components of the magnetic field and the flow speed are generally consistent between the two data sets.The ion number density and the dynamic pressure measured by THEMIS in near-Earth space are lower than those in the OMNI database,suggesting possible variation in the solar wind environment while propagating from the L1 point to near-Earth space.We further show two examples in which near-Earth solar wind measurements are applied in calculating the magnetopause location and in quantifying the magnetic field response to interplanetary shocks.Both examples suggest that using solar wind data from near-Earth space achieves better results than using solar wind data from the L1 point.These results provide validation of THEMIS-B and THEMIS-C as an alternative monitor of the near-Earth solar wind environment.
文摘A continuous hot embossing method is reported in this paper. The continuous means that the extruder and the hot embossing equipment is used in series, the polymer film is embossed after extrusion immediately. The basic principle of this method, the key design point and the corresponding operate process of the embossing equipment is described in this paper. The polymer diffuser with micro-lens matrix on its surface is designed and the optical properties are simulated. Then, the diffuser is fabricated by the embossing equipment. The optical properties of the diffuser are tested and compared with the results of the simulation to verify the reproducibility of the equipment. By this method, the diffuser with large area can be fabricated with high precision of graphic replication, high efficiency and low cost.
基金supported by the Fundamental Research Funds for the Central Universities(No.3132023503).
文摘The notorious dendrite and infinite volume change seriously restrict the advancement of lithium metal anodes(LMAs),during the long-term process of stripping/plating.Herein,the nanosheets of metal fluoride(CoF_(2))and metal nitride(CoN)with magnificent lithiophilicity on the nickel(Ni)foam are designed as the“regulator”to uniform the Li plating and build stronger solid electrolyte interface(SEI)layer for dendrite free LMAs.The Ni foam offers abundant space to receive deposited Li metal.The CoN nanosheets can guarantee the fast transfer of electrons,which provides a stable interface of Li^(+)reduction.Moreover,the nanosheet structure with lithiophilicity would accelerate the move of Li+and decrease the nucleation barrier,due to the high lattice-matching of Li and CoN.Meanwhile,the CoF_(2) could increase the content of F(LiF)in the SEI layer,which enhances the strength and avoids the destruction of SEI layer.With the cooperation of CoN and CoF_(2),the composited anode(Li/NF@CNCF)exhibits ultra-long cycle performance(more than 1200 h)and fantastic structure stability at 1 mA·cm^(-2) with 1 mAh·cm^(-2).Based on the LiFePO_(4) and Li/NF@CNCF,the full cells deliver excellent specifical capacity and steady coulombic efficiency.The strategy contributes an effective approach to alleviate the issues of lithium metal anodes in the field of LMAs.
基金supported by the National Natural Science Foundation of China(Nos.41702225,42030306)the special Foundation(GASI-GEOGE-02)from State Oceanic Administrationthe 111 Project(No.B18048)。
文摘Mantle peridotite xenoliths in Jiaohe City,located near the northern part of the Tan-Lu fault,are key evidence for constraining the nature and evolution of the subcontinental lithospheric mantle(SCLM)of the NE China.Geochemical characteristics of Jiaohe peridotite xenoliths have been well studied,whereas the microstructures and associated fabrics remain poorly known.We report here major element composition of the constituent minerals,P-T conditions,microstructure,lattice preferred orientations(LPOs)of a set of xenoliths having coarse-grained and granuloblastic to porphyroclastic textures.These xenoliths are characterized by forsterite content of 89-91 in olivine.Dislocation microstructures,in olivine crystals revealed by oxidation decoration technique,are characterized by free dislocation,dislocation walls,dislocation loops and subgrains.Microstructures and deformation mechanism maps indicate that dislocation creep is the dominant deformation mechanism of almost anhydrous olivine in the SCLM.In most samples,the observed LPOs of olivine are typical A-type fabric.Stresses measured in the xenoliths using several olivine piezometers are~2.7-8.5 MPa.The equilibration temperature conditions,calculated using several geo-thermometers,indicate the equilibrium temperature condition of peridotites in a range of 891 to 993℃.These results provide rheological constraint on the deformation of the SCLM in Jiaohe.Combined with the data for mantle xenoliths from adjacent regions,a heterogeneous evolution of the lithosphere deformation is inferred at the Jiaohe region.We propose that characteristics of the studied peridotite may be related to the Tan-Lu fault.
基金Financial support from the National Natural Science Foundation of China (No. 51973020)。
文摘We use a single-molecule self-assembled layer of an aromatic organophosphonic acid(2PACz) to modify the cathode interface layer in inverted organic solar cells(OSCs). The modified OSCs not only have an obvious improvement in power conversion efficiency(PCE), but also demonstrate greatly enhanced air stability. Ultraviolet photoelectron spectroscopy shows that the work function of cathode interlayer after modification by 2PACz is more suitable for electron extraction. In addition, the surface energy is reduced without affecting the film deposition, which will be beneficial to reduce the interfacial traps. As a result,the PCE of OSCs based on the PBDB-T:IT-M system is increased, and its stability in air is greatly improved(remaining 88% of its initial PCE after 555 h in air). Therefore, we provide a new strategy for constructing high-performance non-fullerene OSCs with enhanced air stability.
基金This paper was partially supported by the Natural Science Foundation of China under Grant No. 51605348, the Natural Science Foundation of Hubei province under Grants No. 2016CFB116, and the Project of China Postdoctoral Science Foundation under Grant No. 2015M572208.
基金supported by the Project of the National Natural Science Foundation of China(Grant No.51172135)the Young Scientists Fund of the National Natural Science Foundation of China(Grant No.51002092)+1 种基金Research and Special Projects of the Education Department of Shaanxi Province(Grant No.12JK0445)the Graduate Innovation Fund of Shaanxi University of Science and Technology(SUST-A04)
文摘Bi_(1-x)Tb_xFeO_3 thin films were prepared on SnO_2(fluorine doped tin oxide) substrates by a sol—gel method.The structural and electrical properties of the BiFeO_3 thin films were characterized and tested.The results indicated that the diffraction peak of the Tb-doped BiFeO_3 films was shifted towards right as the doping amounts were increased.The structure was transformed from the rhombohedral to tetragonal/orthorhombic phase.The Bi_(0.89)Tb_(0.11)FeO_3 thin film showed the well-developed P—E loops,which enhanced remnant polarization(Pr = 88.05 μC/cm^2) at room temperature.The dielectric constant and dielectric loss of Bi_(0.89)Tb_(0.11)FeO_3 thin film at 100 kHz were 185 and 0.018,respectively.Furthermore,the Bi_(0.89)Tb_(0.11)FeO_3 thin film showed a relatively low leakage current density of 2.07 × 10^(-5) A/cm^2 at an applied electric field of 150 kV/cm.The Xray photoelectron spectroscopy(XPS) spectra indicated that the presence of Fe^(2+) ions in the Bi_(0.89)Tb_(0.11)FeO_3thin film was less than that in the pure BiFeO_3.
基金supported by the National Science Foundation of China(No.61631166004)Shenzhen KQTD project(No.KQTD20180411143514543)+1 种基金Shenzhen JCYJ project(No.JCYJ20180504165831308)and Shenzhen DRC project[2018]1433partially supported by Doctoral Scientific Research Startup Foundation of Shaanxi University of Science and Technology(No.2019BJ-30).
文摘Recently,flexible oxide epitaxial thin films are of increasing interests owing to their excellent physical properties and wide applications.The oxide epitaxial thin films with flexible,lightweight and wearable are promising for the applications in flexible and wearable devices,such as flexible sensors,flexible detectors,flexible oscillators,flexible spintronics,wearable displays and electronic skin,etc.This review aims to summarize the fabrication,physical properties and applications of the flexible oxide epitaxial thin films for wearable electronics in most recent few years.The fabrication of flexible oxide epitaxial thin films reviewed here mainly includes the deposition on flexible substrates at high temperature and epitaxial lift-off(ELO)from rigid substrates.The physical properties and applications of flexible oxide epitaxial thin films reviewed here chiefly focus on the area of electricity and magnetism,including stable and tunable physical properties in the flexible oxide epitaxial thin films.In final,the perspectives and challenges of flexible oxide thin films for wearable electronics have been also addressed.
基金The work was supported by the National 973 projects of China(No.2015CB654603)the National Natural Science Foundation of China(No.61471290,61631166004).
文摘Dielectrics used for energy storage are highly desired for power electronics and pulse power applications and the polymer capacitors are the main commercial ones available.The development of flexible electronics and wearable devices require the relative materials being flexible.Besides,high temperature resistance is also desired because of the rising demand for high power devices and large electricity under elevated temperature.The polymer dielectrics for polymer capacitors are flexible but with relatively low working temperature normally less than 100℃.Therefore,fabricating a dielectric material to satisfy the flexibility and high working temperature simultaneously is still a great challenge.Here we propose one solution by demonstrating a hand-exfoliated fluorophlogopite film with micrometer scale thickness.Among which,the mica film with a thickness of around 10μm(Mica-10)exhibits the inorganic-like temperature stability even polymer-like flexibility.From 25℃to 200℃,Mica-10 has an energy density of around 11.27 J/cm^(3)with a variation within 2%,accompanied by a charge-discharge efficiency of around 95%at an electric field of 500 MV/m.Meanwhile,the thin thickness makes Mica-10 flexible,enabling its excellent flexibility and durability.This work revives the traditional material,mica,providing a way for high-temperature energy storage applications.
基金supported by the National Key R&D Program of China(Grant No.2018YFC1106300 , 2017YFC1105000)the National Natural Science Foundation of China(Grant No.51802340,31870956,31771041 , 81672227)+6 种基金the Science and Technology Project of Guangdong Province-Doctoral startup fund of 2017(Grant No.2017A030310318)the Frontier Science Key Research Programs of CAS(Grant No.QYZDB-SSW-JSC030)the Strategic Priority Research Program of CAS(Grant No.XDA16021000)the Shenzhen significant strategy layout project(Grant No.JCYJ20170413162104773)the Economic,Trade and information Commission of Shenzhen Municipality“Innovation and Industry Chain”(Grant No.20170502171625936)the Beijing Municipal Natural Science Foundation(Grant No.7161001)Beijing Municipal Commission of Health and Family Planning(Grant No.PXM2018_026275_000001).
文摘There is a need for synthetic grafts to reconstruct large bone defects using minimal invasive surgery.Our previous study showed that incorporation of Sr into bioactive borate glass cement enhanced the osteogenic capacity in vivo.However,the amount of Sr in the cement to provide an optimal combination of physicochemical properties and capacity to stimulate bone regeneration and the underlying molecular mechanism of this stimulation is yet to be determined.In this study,bone cements composed of bioactive borosilicate glass particles substituted with varying amounts of Sr(0 mol%to 12 mol%SrO)were created and evaluated in vitro and in vivo.The setting time of the cement increased with Sr substitution of the glass.Upon immersion in PBS,the cement degraded and converted more slowly to HA(hydroxyapatite)with increasing Sr substitution.The released Sr2+modulated the proliferation,differentiation,and mineralization of hBMSCs(human bone marrow mesenchymal stem cells)in vitro.Osteogenic characteristics were optimally enhanced with cement(designated BG6Sr)composed of particles substituted with 6mol%SrO.When implanted in rabbit femoral condyle defects,BG6Sr cement supported better peri-implant bone formation and bone-implant contact,comparing to cements substituted with 0mol%or 9mol%SrO.The underlying mechanism is involved in the activation of Wnt/β-catenin signaling pathway in osteogenic differentiation of hBMSCs.These results indicate that BG6Sr cement has a promising combination of physicochemical properties and biological performance for minimally invasive healing of bone defects.
基金This work was supported by grants from the National Natural Science Foundation of China(No.51272274,81672227,51372170)Shenzhen Peacock Program(No.110811003586331)Shenzhen Science and Technology Research funding(No.CXZZ 20150401152251209,JSGG20151030140325149,JSGG20150331154931068,CXZZ20140417113430716)and partially from Hong Kong General Research Fund.
文摘In osteoporosis scenario, tissue response to implants is greatly impaired by the deteriorated boneregeneration microenvironment. In the present study, a Mg-containing akermanite (Ak) ceramic wasemployed for the treatment of osteoporotic bone defect, based on the hypothesis that both beneficialions (e.g. Mg^2+ ect.) released by the implants and the weak alkaline microenvironment pH (μe-pH) itcreated may play distinct roles in recovering the abnormal bone regeneration by stimulating osteoblasticanabolic effects. The performance of Ak, b-tricalcium phosphate (β-TCP) and Hardystone (Har) in healinga 3 mm bone defect on the ovariectomized (OVX) osteoporotic rat model was evaluated. Our resultsindicated that, there's more new bone formed in Ak group than in β-TCP or Har group at week 9. Theinitial me-pHs of Ak were significantly higher than that of the β-TCP and Blank group, and this weakalkaline condition was maintained till at least 9 weeks post-surgery. Increased osteoblastic activity whichwas indicated by higher osteoid secretion was observed in Ak group at week 4 to week 9. An intermediatelayer which was rich in phosphorus minerals and bound directly to the new forming bone wasdeveloped on the surface of Ak. In a summary, our study demonstrates that Ak exhibits a superior boneregenerative performance under osteoporosis condition, and might be a promising candidate for thetreatment of osteoporotic bone defect and fracture.
基金support by the National Natural Science Foundation of China(21771159,22071212)Qinglan Project of Jiangsu Province of China.
文摘Oxychalcogenides have been drawn much attention to be explored as nonlinear optical(NLO)materials in recent years.To date,all the NLO oxychalcogenides crystallize in low dimensional structures.Herein,a new oxysulfide K_(2)Ba_(0.5)Ga_(9)O_(2)S_(13) was obtained via three-dimensional(3D){[Ga_(9)O_(2)S_(13)]^(3-)}_(∞)polyanionic framework.As the first oxychalcogenide with 3D NLO-acitve polyanionic framework,K_(2)Ba_(0.5)Ga_(9)O_(2)S_(13) has a wide band gap of 3.72 eV,and exhibits a high laser-induced damage threshold(LIDT,17×AgGaS_(2)).It presents moderate phase-matchable NLO response of 0.5×AgGaS_(2) at 2.1μm and 2×KH_(2)PO_(4) at 1.064μm.The theoretical calculation results indicate that the NLO response is mainly contributed from[Ga(2)S4]unit-built[Ga(2)_(3)S_(10)]windmill-like motif.This work may stimulate the exploration of more NLO oxychalcogenides with balanced performances.
基金supported by the National Natural Science Foundation of China(No.52001021)the China Postdoctoral Science Foundation(No.2019M660453)the Postdoctoral Research Foundation of Shunde Graduate School of University of Science and Technology Beijing(No.2020BH009)。
文摘The effect of thermoacidophilic archaeon Metallosphaera cuprina(M.cuprina)on the corrosion of Q235 carbon steel in its culture medium was investigated in this work.In the sterile culture medium,the carbon steels showed uniform corrosion morphologies and almost no corrosion products covered the sample surface during 14 days of immersion test.In the presence of M.cuprina,some corrosion pits appeared on the surface of carbon steels in the immersion test,exhibiting typical localized corrosion morphologies.Moreover,the sample surfaces were covered by a large number of insoluble precipitates during the immersion.After 14 days,the thickness of precipitates reached approximately 50μm.The results of weight loss test and electrochemical test demonstrated that the carbon steels in the M.cuprina-inoculated culture medium had higher corrosion rate than that in the sterile culture medium.The oxygen concentration cell caused by M.cuprina biofilms resulted in localized corrosion behavior,and the ferrous oxidation ability of M.cuprina accelerated the anodic dissolution of carbon steels,thus promoting the corrosion process of carbon steels.
基金financially supported by the Key Project of National Natural Science Foundation of China(No.11832007)the Applied Basic Research Program of Sichuan(No.19YYJC1846)the Science and Technology Achievement Transfer and Transformation of Sichuan(No.20ZHSF0154)。
文摘It is a challenge to reduce the dielectric loss and increase the tunability of pure barium strontium titanate(BST)films for microwave tunable application because these two properties change simultaneously.Herein,a novel composite of strontium titanate(ST)and potassium-doped BST(KBST)has been designed as ST/KBST/ST sandwich-type film with various ST and KBST layers.X-ray diffraction patterns show that the film exhibits cubic perovskite polycrystalline structure composed of BST and ST phase,mainly grow along(110)crystal plane with average grain size of less than 20 nm and decreasing BST phase/ST phase ratio with increasing film thickness.Scanning electron microscope shows that no interfacial layer can be observed,indicating that ST and KBST are fully compounded.Low dielectric loss and high tunability at-10-10 V and stable and excellent dielectric properties at 1 GHz are achieved,meeting the needs of microwave tunable application at high frequency.The surface structures are also studied by other analysis methods,and ST/MgBST/ST sandwich-type film is compared.
文摘The authors regret that the printed version of the above article contained a number of errors which were not identified during the proofing stage.The correct and final version follows.The authors would like to apologies for any inconvenience caused.The authors regret:1.“…and the underlying molecular mechanism of this simulation is yet to be determined”,Page 335,needs to be corrected to“and the underlying molecular mechanism of this stimulation is yet to be determined”.