The transition metal trichalcogenides(TMTs)with quasi-one-dimensional(quasi-1D)layered crystal structure represent a unique platform to explore intriguing physical properties.Herein,we report the successful growth of ...The transition metal trichalcogenides(TMTs)with quasi-one-dimensional(quasi-1D)layered crystal structure represent a unique platform to explore intriguing physical properties.Herein,we report the successful growth of a new TMT TiSe_(3)single crystal by using a high-pressure and high-temperature technique.The crystal structure of TiSe_(3)was determined by measuring the single-crystal x-ray diffraction and selected area electron diffraction.The 1D chain-like structure along the b-axis is formed by the TiSe_(6)prisms which share their tops and bottoms with each other.TiSe_(3)is a narrow band gap semiconductor with electron-type carriers under ambient conditions identified by the electrical and Hall effect measurements.It exhibits a pressure-induced semiconductor-to-metal transition around 4 GPa.As the pressure further increases to~6 GPa,a pressure-induced Lifshitz transition occurs,as indicated by the electrical transport measurements,high-pressure crystal structure characterizations,and electronic band structure calculations.展开更多
To investigate a possible therapeutic mechanism of cell therapy in the field of cerebral palsy using granulocyte-colony stimulating factor（G-CSF）-mobilized peripheral blood mononuclear cells（m PBMCs）,we compared t...To investigate a possible therapeutic mechanism of cell therapy in the field of cerebral palsy using granulocyte-colony stimulating factor（G-CSF）-mobilized peripheral blood mononuclear cells（m PBMCs）,we compared the expression of inflammatory cytokines and neurotrophic factors in PBMCs and m PBMCs from children with cerebral palsy to those from healthy adult donors and to cord blood mononuclear cells donated from healthy newborns.No significant differences in expression of neurotrophic factors were found between PBMCs and m PBMCs.However,in cerebral palsy children,the expression of interleukin-6 was significantly increased in m PBMCs as compared to PBMCs,and the expression of interleukin-3 was significantly decreased in m PBMCs as compared to PBMCs.In healthy adults,the expression levels of both interleukin-1βand interleukin-6 were significantly increased in m PBMCs as compared to PBMCs.The expression of brain-derived neurotrophic factors in m PBMC from cerebral palsy children was significantly higher than that in the cord blood or m PBMCs from healthy adults.The expression of G-CSF in m PBMCs from cerebral palsy children was comparable to that in the cord blood but significantly higher than that in m PBMCs from healthy adults.Lower expression of pro-inflammatory cytokines（interleukin-1β,interleukin-3,and-6）and higher expression of anti-inflammatory cytokines（interleukin-8 and interleukin-9）were observed from the cord blood and m PBMCs from cerebral palsy children rather than from healthy adults.These findings indicate that m PBMCs from cerebral palsy and cord blood mononuclear cells from healthy newborns have the potential to become seed cells for treatment of cerebral palsy.展开更多
Li(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO) solid garnet-type electrolyte has been widely reported due to its outstanding safety and electrochemical stability.However,the inherent rigidity and brittleness of LLZTO lead...Li(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO) solid garnet-type electrolyte has been widely reported due to its outstanding safety and electrochemical stability.However,the inherent rigidity and brittleness of LLZTO lead to poor contact with anode/cathode and the operation failure of full cells.Herein,the dual-interlayers are constructed as the fast interfacial ion-migration channel by using Ti_(3)C_(2)T_(x)(MXene,Txis-O,-OH,-F) with trace ionic liquid(IL),which promote the intimate contact between LLZTO and anode/cathode and suppress Li-dendrites growth.Notably,IL can wet the cathode to promote intimate interface contact and be decomposed into some inorganic compounds(such as Li3N,LiF,and Li2Sx),resulting in reduced interfacial resistance and fast Li-ion transportation.Consequently,in the prepared Li-symmetric cell,the interfacial resistance on the anode side plunges to 33.1 Ω cm^(-2),and stably maintains over 1000 h without short circuit at 0.05 mA cm^(-2).The full cell of Li|LiFePO4delivers a high initial capacity of 158.52 mA h g^(-1)and outstanding retention of 90.18% after 100 cycles at 60℃ and 0.2 C.Our work provides an efficient strategy to design dual-interlayers between LLZTO and anode/cathode for the interfacial modification to enhance the performance of solid garnet batteries.展开更多
AIM:To find the significant altered proteins in agerelated macular degeneration(AMD)patients as potential biomarkers of AMD.METHODS:A comparative analysis of the protein pattern of AMD patients versus healthy controls...AIM:To find the significant altered proteins in agerelated macular degeneration(AMD)patients as potential biomarkers of AMD.METHODS:A comparative analysis of the protein pattern of AMD patients versus healthy controls was performed by means of proteomic analysis using twodimensional gel electrophoresis followed by protein identification with MALDI TOF/TOF mass spectrometry.RESULTS:We identified 28 proteins that were significantly altered with clinical relevance in AMD patients.These proteins were involved in a wide range of biological functions including immune responses,growth cytokines,cell fate determination,wound healing,metabolism,and anti-oxidance.CONCLUSION:These results demonstrate the capacity of proteomic analysis of AMD patient plasma.In addition to the utility of this approach for biomarker discovery,identification of alterations in endogenous proteins in the plasma of AMD patient could improve our understanding of the disease pathogenesis.展开更多
The structure of Ni active sites supported on amorphous silica-alumina supports with different contents of Al_(2)O_(3)loadings in relation to their activities in ethylene oligomerization were investigated.Two kinds of...The structure of Ni active sites supported on amorphous silica-alumina supports with different contents of Al_(2)O_(3)loadings in relation to their activities in ethylene oligomerization were investigated.Two kinds of Ni sites were detected by in situ FTIR-CO and H_(2)-TPR experiments,that are Ni^(2+)cations as grafted on weak acidic silanols and Ni^(2+)cations at ion-exchange positions.The ethylene oligomerization activities of these Ni/ASA catalysts were found an ascending tendency as the Al_(2)O_(3)loading decreased,which could be attributed to the enriched concentration of Ni^(2+)species on acidic silanols with a weaker interaction with the amorphous silica-alumina support.These Ni^(2+)species were more easily to be evolved into Ni^(+)species,which has been identified to be the active sites of ethylene oligomerization.Thus,it seems reasonable to conclude that Ni^(2+)species grafted on acidic silanols were the precursors of active sites.展开更多
Water electrolysis via alkaline hydrogen evolution reaction(HER)is a promising approach for large-scale production of high-purity hydrogen at a low cost,utilizing renewable and clean energy.However,the sluggish kineti...Water electrolysis via alkaline hydrogen evolution reaction(HER)is a promising approach for large-scale production of high-purity hydrogen at a low cost,utilizing renewable and clean energy.However,the sluggish kinetics derived from the high energy barrier of water dissociation impedes seriously its practical application.Herein,a series of hybrid Pt nanoclusters/Ru nanowires(Pt/Ru NWs)catalysts are demonstrated to accelerate alkaline HER.And the optimized Pt/Ru NWs(10%wt Pt)exhibits exceptional performance with an ultralow overpotential(24 mV at 10 mA cm^(-2)),a small Tafel slope(26.3 mV dec^(-1)),and long-term stability,outperforming the benchmark commercial Pt/C-JM-20%wt catalyst.This amazing performance also occurred in the alkaline anion-exchange membrane water electrolysis devices,where it delivered a cell voltage of about 1.9 V at 1 A cm^(-2)and an outstanding stability(more than 100 h).The calculations have revealed such a superior performance exhibited by Pt/Ru NWs stems from the formed heterointerfaces,which significantly reduce the energy barrier of the decisive rate step of water dissociation via cooperative-action between Pt cluster and Ru substance.This work provides valuable perspectives for designing advanced materials toward alkaline HER and beyond.展开更多
Monoclinicα-MoP_(2),with the OsGe2-type structure(space group C2/m,Z=4)and lattice parameters a=8.7248(11)Å,b=3.2322(4)Å,c=7.4724(9)Å,andβ=119.263°,was synthesized under a pressure of 4~GPa at a ...Monoclinicα-MoP_(2),with the OsGe2-type structure(space group C2/m,Z=4)and lattice parameters a=8.7248(11)Å,b=3.2322(4)Å,c=7.4724(9)Å,andβ=119.263°,was synthesized under a pressure of 4~GPa at a temperature between 1100℃and 1200℃.The structure ofα-MoP_(2) and its relationship to other transition metal diphosphides are discussed.Surprisingly,the ambient pressure phase orthorhombicβ-MoP_(2)(space group Cmc21)is denser in structure thanα-MoP_(2).Room-temperature high-pressure x-ray diffraction studies exclude the possibility of phase transition fromβ-MoP_(2) to α-MoP_(2),suggesting thatα-MoP_(2) is a stable phase at ambient conditions;this is also supported by the total energy and phonon calculations.展开更多
Tunable carrier density plays a key role in the investigation of novel transport properties in three-dimensional topological semimetals.We demonstrate that the carrier density,as well as the mobility,of Dirac semimeta...Tunable carrier density plays a key role in the investigation of novel transport properties in three-dimensional topological semimetals.We demonstrate that the carrier density,as well as the mobility,of Dirac semimetal Cd_(3)As_(2) nanoplates can be effectively tuned via in situ thermal treatment at 350 K for one hour,resulting in non-monotonic evolution by virtue of the thermal cycling treatments.The upward shift of Fermi level relative to the Dirac nodes blurs the surface Fermi-arc states,accompanied by an anomalous phase shift in the oscillations of bulk states,due to a change in the topology of the electrons.Meanwhile,the oscillation peaks of bulk longitudinal magnetoresistivity shift at high fields,due to their coupling to the oscillations of the surface Fermi-arc states.Our work provides a thermal control mechanism for the manipulation of quantum states in Dirac semimetal Cd_(3)As_(2) at high temperatures,via their carrier density.展开更多
A new bismuth-based halide double perovskite Cs_(2)KBiCl_(6) was isolated successfully through solid-state reactions and investigated using X-ray and neutron diffraction.Rather than an ordered structure,the crystal st...A new bismuth-based halide double perovskite Cs_(2)KBiCl_(6) was isolated successfully through solid-state reactions and investigated using X-ray and neutron diffraction.Rather than an ordered structure,the crystal structure consists of shifted Cs,K,Bi,and Cl sites from the ideal positions with fractional occupancy in compensation,leading to variable local coordination of Cs^(+)ions,as revealed by^(133)Cs solid-state nuclear magnetic resonance spectroscopy.Cs_(2)KBiCl_(6) displays volume hysteresis at 5-298 K range upon heating and cooling.The Cs_(2)KBiCl_(6) has a direct bandgap of 3.35(2)eV and red-shift luminescence of around 600 nm upon Mn doping compared with the Na analogue.The stabilization of disordered structure in Cs_(2)KBiCl_(6) is related to two factors including the large-sized K^(+)cation which prefers to coordinate with more than six Cl^(-),and the Bi^(3+)with 6s^(2) lone pair which has a preference for a local asymmetric environment.These findings could have general application and help to understand the structure and property of halide perovskites.展开更多
The van der Waals(vdW)MnSb4Te7is a newly synthesized antiferromagnetic(AFM)topological insulator hosting a robust axion insulator state irrelative to the specific spin structure.However,the intrinsic hole doped charac...The van der Waals(vdW)MnSb4Te7is a newly synthesized antiferromagnetic(AFM)topological insulator hosting a robust axion insulator state irrelative to the specific spin structure.However,the intrinsic hole doped character of MnSb_4Te_7makes the Fermi level far away from the Dirac point of about 180 meV,which is unfavorable for the exploration of exotic topological properties such as the quantum anomalous Hall effect(QAHE).To shift up the Fermi level close to the Dirac point,the strategy of partially replacing Sb with Bi as Mn(Sb_(1-x)Bi_(x))_(4)Te_(7)was tried and the magnetotransport properties,in particular,the anomalous Hall effect,were measured and analyzed.Through the electron doping,the anomalous Hall conductanceσAH changes from negative to positive between x=0.3 and 0.5,indicative of a possible topological transition.Besides,a charge neutrality point(CNP)also appears between x=0.6 and 0.7.The results would be instructive for further understanding the interplay between nontrivial topological states and the magnetism,as well as for the exploration of exotic topological properties.展开更多
We report the nontrivial topological states in an intrinsic type-Ⅱ superconductor BaSn_(5)(T_(c)∼4.4 K)probed by measuring the magnetization,specific heat,de Haas–van Alphen(dHvA)effect,and by performing first-prin...We report the nontrivial topological states in an intrinsic type-Ⅱ superconductor BaSn_(5)(T_(c)∼4.4 K)probed by measuring the magnetization,specific heat,de Haas–van Alphen(dHvA)effect,and by performing first-principles calculations.The first-principles calculations reveal a topological nodal ring structure centered at the H point in the k_(z)=πplane of the Brillouin zone,which could be gapped by spin-orbit coupling(SOC),yielding relatively small gaps below and above the Fermi level of about 0.04 eV and 0.14 eV,respectively.The SOC also results in a pair of Dirac points along theΓ–A direction,located at∼0.2 eV above the Fermi level.The analysis of the dHvA quantum oscillations supports the calculations by revealing a nontrivial Berry phase originating from the hole and electron pockets related to the bands forming the Dirac cones.Thus,our study provides an excellent avenue for investigating the interplay between superconductivity and nontrivial topological states.展开更多
Characterization of Fermi surface of the BaSn3 superconductor(Tc~ 4.4K)by de Haas–van Alphen(dHvA)effect measurement reveals its non-trivial topological properties.Analysis of non-zero Berry phase is supported by the...Characterization of Fermi surface of the BaSn3 superconductor(Tc~ 4.4K)by de Haas–van Alphen(dHvA)effect measurement reveals its non-trivial topological properties.Analysis of non-zero Berry phase is supported by the ab initio calculations,which reveals a type-II Dirac point setting and tilting along the high symmetric K–H line of the Brillouin zone,about 0.13 eV above the Fermi level,and other two type-I Dirac points on the high symmetric Г–A direction,but slightly far below the Fermi level.The results demonstrate BaSn3 as an excellent example hosting multiple Dirac fermions and an outstanding platform for studying the interplay between nontrivial topological states and superconductivity.展开更多
The enduring enigma surrounding the near-infrared(NIR)emission of Mn^(2+)continues to ignite intense academic discussions.Numerous hypotheses have emerged from extensive research endeavors to explain this phenomenon,s...The enduring enigma surrounding the near-infrared(NIR)emission of Mn^(2+)continues to ignite intense academic discussions.Numerous hypotheses have emerged from extensive research endeavors to explain this phenomenon,such as the formation of Mn^(2+)-Mn^(2+)ion pairs,Mn^(2+)occupying cubically coordinated sites,as well as conjectures positing the involvement of Mn3+oxidized from Mn^(2+)or defects.Despite these diverse and valuable insights,none of the hypotheses have yet achieved broad consensus.In this study,we have observed prolonged fluorescence lifetimes(~10ms)for the NIR emissions of Mn^(2+)ions,hinting at these ions occupying the high-symmetry octahedral sites inherent to the garnet lattice.This inference is supported by the corroborating results from X-ray absorption fine structure analysis and first-principles calculations.The intense crystal field of octahedral sites,similar to that of AlO6,facilitates the splitting of d-d energy levels,thereby inducing a red-shift in the emission spectrum to the NIR region due to the transition ^(4)T_(1)(4G)→ ^(6)A_(n)(6S)of isolated Mn^(2+).Our findings not only offer a plausible rationale for the NIR emission exhibited by other Mn^(2+)-activated garnet phosphors but also pave a definitive route towards understanding the fundamental mechanisms responsible for the NIR emission of Mn^(2+)ions.展开更多
Materials exhibiting time-dependent phosphorescence color(TDPC)are attractive,but generally suffer from complex preparation processes and low-color contrast.Herein,molecular aggregation regulation of 1-pyrenecarboxyli...Materials exhibiting time-dependent phosphorescence color(TDPC)are attractive,but generally suffer from complex preparation processes and low-color contrast.Herein,molecular aggregation regulation of 1-pyrenecarboxylic acid(PyC)in the konjac glucomannan(KGM)matrix is proposed to realize high-contrast TDPC.The steric hindrance of KGM enables isolated state,carboxyl dimer,andπ-stacking-induced multimers of PyC with different phosphorescence wavelengths and lifetimes to coexist,leading to a typical TDPC evolution from red to blue-green.The TDPC shows remarkable phosphorescence wavelength shift up to 182 nm and phosphorescence lifetime up to 788.43 ms,readily recognized by the naked eye.In addition,KGM,an edible natural polysaccharide,displays decent rheological properties suitable for screen printing,film casting,and 3D printing,making PyC-KGM an eco-friendly tool for multi-dimensional information security applications.The work provides a simple yet efficient method for high-contrast TDPC materials and affords a promising material for high-level dynamic information encryption and anti-counterfeiting.展开更多
In two-dimensional van der Waals magnetic materials,the interplay between magnetism and electron correlation can give rise to new ground states and lead to novel transport and optical properties.A fundamental question...In two-dimensional van der Waals magnetic materials,the interplay between magnetism and electron correlation can give rise to new ground states and lead to novel transport and optical properties.A fundamental question in these materials is how the electron correlation manifests and interacts with the magnetic orders.In this study,we demonstrate that the recently discovered 2D antiferromagnetic material,CrSBr is a Mott insulator,through the combined use of resonant and temperature-dependent angle-resolved photoemission spectroscopy techniques,supplemented by dynamical mean-field theory analysis.Intriguingly,we found that as the system transitions from the antiferromagnetic to the paramagnetic phases,its Mott bands undergo a reconfiguration,and a coherent-incoherent crossover,driven by the dissolution of the magnetic order.Our findings reveal a distinctive evolution of band structure associated with magnetic phase transitions,shedding light on the investigation of the intricate interplay between correlation and magnetic orders in strongly correlated van der Waals magnetic materials.展开更多
Impedance matching is important for achieving high-efficiency microwave absorbers. The high conductivity of dielectric loss materials such as pure metals and carbon nanomaterials generally results in poor absorption o...Impedance matching is important for achieving high-efficiency microwave absorbers. The high conductivity of dielectric loss materials such as pure metals and carbon nanomaterials generally results in poor absorption owing to the low impedance matching between the absorbers and air. Carbon nanostructures are very promising candidates for high-efficiency absorption because of their attractive features including low density, high surface area, and good stability. Herein, a new strategy is proposed to improve the impedance matching of dielectric loss materials using electrospun carbon nanofibers as an example. The carbon nanofibers are coated with specifically designed gradient multilayer nanofilms with gradually increasing electroconductibility synthesized by doping ZnO with different A1203 content （AZO） by atomic layer deposition. The gradient nanofilms are composed of five layers of dielectric films, namely, pure A1203, AZO （5：1, the pulse cycle ratio of ZnO to A1203）, pure ZnO, AZO （10：1）, and AZO （20：1）. The versatile gradient films serve as intermediate layers to tune the impedance matching between air and the carbon nanofiber surfaces. Therefore, the carbon nanofibers coated with gradient films of rationally selected thicknesses exhibit remarkably enhanced microwave absorption performance, and the optimal reflection loss reaches -58.5 dB at 16.2 GHz with a thickness of only 1.8 mm. This work can help further understand the contribution of impedance matching to microwave absorption. Our strategy is general and can be applied to improve the absorption properties of other dielectric loss materials and even for applications in other fields.展开更多
Immune therapy based on programmed death-ligand 1(PD-L1)is widely used to treat human tumors.The current strategies to improve immune checkpoint blockade therapy fail in rescuing increased expression of PD-L1 in tumor...Immune therapy based on programmed death-ligand 1(PD-L1)is widely used to treat human tumors.The current strategies to improve immune checkpoint blockade therapy fail in rescuing increased expression of PD-L1 in tumor issues.Here,we for the first time synthesized the metal-organic framework(MOF)nanocrystals of rare-earth element dysprosium(Dy)coordinated with tetrakis(4-carboxyphenyl)porphyrin(TCPP),which show well-defined two-dimensional morphologies.The MOF nanocrystals of Dy-TCPP could apparently reduce PD-L1 expression in tumor cells both in vitro and in vivo,and therefore display effective tumor treatment through immune therapy without any immune checkpoint inhibitor drugs.Considering the sensitivity of TCPP ligand toward ultrasound,the prepared Dy-TCPP can also realize sonodynamic therapy(SDT)besides immune therapy.In addition,the Dy-TCPP nanocrystals can efficiently obtain T_(2)-weight magnetic resonance imaging(MRI)of tumor sites.Our study provides the Dy-TCPP nanocrystals as promising diagnostic MRI-guided platforms for the combined treatment on tumors with SDT and immune therapy.Moreover,this strategy succeeds in reducing the elevated expression of PD-L1 in tumor cells,which might serve as a novel avenue for tumor immunotherapy in future.展开更多
The electrocatalytic hydrogen evolution reaction(HER)is one of the most promising ways for low-cost hydrogen production in the future.In this work,hetero S atoms were introduced into the MoO2 to enhance the catalytic ...The electrocatalytic hydrogen evolution reaction(HER)is one of the most promising ways for low-cost hydrogen production in the future.In this work,hetero S atoms were introduced into the MoO2 to enhance the catalytic activity by simultaneously adjusting electron structure,engineering lattice defect,and increasing oxygen vacancies.And the S doped MoO2 nanosheets with proper S doping amount show the enhanced performance for HER.The optimized catalyst shows a small onset overpotential as low as 120 mV,a low overpotential of 176 mV at the current density of 10 mA/cm^2 which is decreased 166 mV compared to that of the pristine MoO2 nanosheets,a low Tafel slope of 57 mV/decade,and a high turnover frequency of 0.13 H2/s per active site at 150 mV.This finding proposes an effective strategy to prepare nonprecious metal oxide catalyst for enhancing HER performance by rationally doping hetero atoms.展开更多
The hydrogen evolution reaction(HER)of molybdenum disulfide(MoS_(2))is limited in alkaline and acid solution because the active sites are on the finite edge with extended basal plane remaining inert.Herein,we activate...The hydrogen evolution reaction(HER)of molybdenum disulfide(MoS_(2))is limited in alkaline and acid solution because the active sites are on the finite edge with extended basal plane remaining inert.Herein,we activated the interfacial S sites by coupling with Ru nanoparticles on the inert basal plane of MoS_(2)nanosheets.The density functional theory(DFT)calculation and experimental results show that the interfacial S electronic structure was modulated.And the results of∆G H*demonstrate that the adsorption of H on the MoS_(2)was also optimized.With the advantage of interfacial S sites activation,the Ru-MoS_(2)needs only overpotential of 110 and 98 mV to achieve 10 mA·cm^(–2)in both 0.5 M H_(2)SO_(4)and ^(1) M KOH solution,respectively.This strategy paves a new way for activating the basal plane of other transition metal sulfide electrocatalysts for improving the HER performance.展开更多
Phonon-assisted photon upconversion(UPC)is an anti-Stokes process in which incident photons achieve higher energy emission by absorbing phonons.This letter studies phonon-assisted UPC in twisted 2D semiconductors,in w...Phonon-assisted photon upconversion(UPC)is an anti-Stokes process in which incident photons achieve higher energy emission by absorbing phonons.This letter studies phonon-assisted UPC in twisted 2D semiconductors,in which an inverted contrast between UPC and conventional photoluminescence(PL)of WSe2 twisted bilayer is emergent.A 4-fold UPC enhancement is achieved in 5.5°twisted bilayer while PL weakens by half.Reduced interlayer exciton conversion efficiency driven by lattice relaxation,along with enhanced pump efficiency resulting from spectral redshift,lead to the rotation-angle-dependent UPC enhancement.The counterintuitive phenomenon provides a novel insight into a unique way that twisted angle affects UPC and light-matter interactions in 2D semiconductors.Furthermore,the UPC enhancement platform with various superimposable means offers an effective method for lighting bilayers and expanding the application prospect of 2D stacked van der Waals devices.展开更多
基金the National Key R&D Program of China(Grant Nos.2023YFA1406100 and 2024YFA1400066)the Open Research Fund of Beijing National Laboratory for Condensed Matter Physics(Grant No.2023BNLCMPKF002)+6 种基金supported by the National Natural Science Foundation of China(Grant Nos.52288102 and 52090020)the S&T Program of Hebei(Grant No.225A1102D)the Open Projects from the State Key Laboratory of Metastable Materials Science and Technology,Yanshan University(Grant No.202301)carried out at the Synergetic Extreme Condition User Facility(SE-CUF)of the Chinese Academy of Sciencessupport from the Analytical Instrumentation Center(Grant No.SPST-AIC10112914)School of Physical Science and Technology(SPST),ShanghaiTech Universitysupported by the Double First-Class Initiative Fund of ShanghaiTech University.
文摘The transition metal trichalcogenides(TMTs)with quasi-one-dimensional(quasi-1D)layered crystal structure represent a unique platform to explore intriguing physical properties.Herein,we report the successful growth of a new TMT TiSe_(3)single crystal by using a high-pressure and high-temperature technique.The crystal structure of TiSe_(3)was determined by measuring the single-crystal x-ray diffraction and selected area electron diffraction.The 1D chain-like structure along the b-axis is formed by the TiSe_(6)prisms which share their tops and bottoms with each other.TiSe_(3)is a narrow band gap semiconductor with electron-type carriers under ambient conditions identified by the electrical and Hall effect measurements.It exhibits a pressure-induced semiconductor-to-metal transition around 4 GPa.As the pressure further increases to~6 GPa,a pressure-induced Lifshitz transition occurs,as indicated by the electrical transport measurements,high-pressure crystal structure characterizations,and electronic band structure calculations.
基金supported by the Research Fund of Hanyang University(HY-2012)
文摘To investigate a possible therapeutic mechanism of cell therapy in the field of cerebral palsy using granulocyte-colony stimulating factor（G-CSF）-mobilized peripheral blood mononuclear cells（m PBMCs）,we compared the expression of inflammatory cytokines and neurotrophic factors in PBMCs and m PBMCs from children with cerebral palsy to those from healthy adult donors and to cord blood mononuclear cells donated from healthy newborns.No significant differences in expression of neurotrophic factors were found between PBMCs and m PBMCs.However,in cerebral palsy children,the expression of interleukin-6 was significantly increased in m PBMCs as compared to PBMCs,and the expression of interleukin-3 was significantly decreased in m PBMCs as compared to PBMCs.In healthy adults,the expression levels of both interleukin-1βand interleukin-6 were significantly increased in m PBMCs as compared to PBMCs.The expression of brain-derived neurotrophic factors in m PBMC from cerebral palsy children was significantly higher than that in the cord blood or m PBMCs from healthy adults.The expression of G-CSF in m PBMCs from cerebral palsy children was comparable to that in the cord blood but significantly higher than that in m PBMCs from healthy adults.Lower expression of pro-inflammatory cytokines（interleukin-1β,interleukin-3,and-6）and higher expression of anti-inflammatory cytokines（interleukin-8 and interleukin-9）were observed from the cord blood and m PBMCs from cerebral palsy children rather than from healthy adults.These findings indicate that m PBMCs from cerebral palsy and cord blood mononuclear cells from healthy newborns have the potential to become seed cells for treatment of cerebral palsy.
基金financially supported by the National Natural Science Foundation of China(NSFC)(52172096)。
文摘Li(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO) solid garnet-type electrolyte has been widely reported due to its outstanding safety and electrochemical stability.However,the inherent rigidity and brittleness of LLZTO lead to poor contact with anode/cathode and the operation failure of full cells.Herein,the dual-interlayers are constructed as the fast interfacial ion-migration channel by using Ti_(3)C_(2)T_(x)(MXene,Txis-O,-OH,-F) with trace ionic liquid(IL),which promote the intimate contact between LLZTO and anode/cathode and suppress Li-dendrites growth.Notably,IL can wet the cathode to promote intimate interface contact and be decomposed into some inorganic compounds(such as Li3N,LiF,and Li2Sx),resulting in reduced interfacial resistance and fast Li-ion transportation.Consequently,in the prepared Li-symmetric cell,the interfacial resistance on the anode side plunges to 33.1 Ω cm^(-2),and stably maintains over 1000 h without short circuit at 0.05 mA cm^(-2).The full cell of Li|LiFePO4delivers a high initial capacity of 158.52 mA h g^(-1)and outstanding retention of 90.18% after 100 cycles at 60℃ and 0.2 C.Our work provides an efficient strategy to design dual-interlayers between LLZTO and anode/cathode for the interfacial modification to enhance the performance of solid garnet batteries.
基金Supported by the Jiangsu Provincial Program of Leading Talents in Traditional Chinese Medicine(No.LJ200911)the Scientific Project Funded by Jiangsu Provincial Administration of Traditional Chinese Medicine(No.LZ11041)
文摘AIM:To find the significant altered proteins in agerelated macular degeneration(AMD)patients as potential biomarkers of AMD.METHODS:A comparative analysis of the protein pattern of AMD patients versus healthy controls was performed by means of proteomic analysis using twodimensional gel electrophoresis followed by protein identification with MALDI TOF/TOF mass spectrometry.RESULTS:We identified 28 proteins that were significantly altered with clinical relevance in AMD patients.These proteins were involved in a wide range of biological functions including immune responses,growth cytokines,cell fate determination,wound healing,metabolism,and anti-oxidance.CONCLUSION:These results demonstrate the capacity of proteomic analysis of AMD patient plasma.In addition to the utility of this approach for biomarker discovery,identification of alterations in endogenous proteins in the plasma of AMD patient could improve our understanding of the disease pathogenesis.
文摘The structure of Ni active sites supported on amorphous silica-alumina supports with different contents of Al_(2)O_(3)loadings in relation to their activities in ethylene oligomerization were investigated.Two kinds of Ni sites were detected by in situ FTIR-CO and H_(2)-TPR experiments,that are Ni^(2+)cations as grafted on weak acidic silanols and Ni^(2+)cations at ion-exchange positions.The ethylene oligomerization activities of these Ni/ASA catalysts were found an ascending tendency as the Al_(2)O_(3)loading decreased,which could be attributed to the enriched concentration of Ni^(2+)species on acidic silanols with a weaker interaction with the amorphous silica-alumina support.These Ni^(2+)species were more easily to be evolved into Ni^(+)species,which has been identified to be the active sites of ethylene oligomerization.Thus,it seems reasonable to conclude that Ni^(2+)species grafted on acidic silanols were the precursors of active sites.
基金supported by the Shanxi Province Natural Science Foundation(20210302124446,202102070301018)the Basic Research Project from Institute of Coal Chemistry,CAS(SCJC-HN-2022-17)the Foundation of State Key Laboratory of Coal Conversion(Grant No.J23-24-909).
文摘Water electrolysis via alkaline hydrogen evolution reaction(HER)is a promising approach for large-scale production of high-purity hydrogen at a low cost,utilizing renewable and clean energy.However,the sluggish kinetics derived from the high energy barrier of water dissociation impedes seriously its practical application.Herein,a series of hybrid Pt nanoclusters/Ru nanowires(Pt/Ru NWs)catalysts are demonstrated to accelerate alkaline HER.And the optimized Pt/Ru NWs(10%wt Pt)exhibits exceptional performance with an ultralow overpotential(24 mV at 10 mA cm^(-2)),a small Tafel slope(26.3 mV dec^(-1)),and long-term stability,outperforming the benchmark commercial Pt/C-JM-20%wt catalyst.This amazing performance also occurred in the alkaline anion-exchange membrane water electrolysis devices,where it delivered a cell voltage of about 1.9 V at 1 A cm^(-2)and an outstanding stability(more than 100 h).The calculations have revealed such a superior performance exhibited by Pt/Ru NWs stems from the formed heterointerfaces,which significantly reduce the energy barrier of the decisive rate step of water dissociation via cooperative-action between Pt cluster and Ru substance.This work provides valuable perspectives for designing advanced materials toward alkaline HER and beyond.
基金Project supported by the National Natural Science Foundation of China (Grant Nos.92065201,11874264,and 11974154)the Starting Grant of ShanghaiTech University and Analytical Instrumentation Center,SPST,ShanghaiTech University (Grant No.SPST-AIC10112914)support from the Natural Science Foundation of Shandong Province,China (Grant No.ZR2022MA004)。
文摘Monoclinicα-MoP_(2),with the OsGe2-type structure(space group C2/m,Z=4)and lattice parameters a=8.7248(11)Å,b=3.2322(4)Å,c=7.4724(9)Å,andβ=119.263°,was synthesized under a pressure of 4~GPa at a temperature between 1100℃and 1200℃.The structure ofα-MoP_(2) and its relationship to other transition metal diphosphides are discussed.Surprisingly,the ambient pressure phase orthorhombicβ-MoP_(2)(space group Cmc21)is denser in structure thanα-MoP_(2).Room-temperature high-pressure x-ray diffraction studies exclude the possibility of phase transition fromβ-MoP_(2) to α-MoP_(2),suggesting thatα-MoP_(2) is a stable phase at ambient conditions;this is also supported by the total energy and phonon calculations.
基金the National Key Research and Development Program of China(Grant No.2016YFA0401003)the National Natural Science Foundation of China(Grant Nos.11804340,11774353,U19A2093,and U1732274)the CAS/SAFEA International Partnership Program for Creative Research Teams of China。
文摘Tunable carrier density plays a key role in the investigation of novel transport properties in three-dimensional topological semimetals.We demonstrate that the carrier density,as well as the mobility,of Dirac semimetal Cd_(3)As_(2) nanoplates can be effectively tuned via in situ thermal treatment at 350 K for one hour,resulting in non-monotonic evolution by virtue of the thermal cycling treatments.The upward shift of Fermi level relative to the Dirac nodes blurs the surface Fermi-arc states,accompanied by an anomalous phase shift in the oscillations of bulk states,due to a change in the topology of the electrons.Meanwhile,the oscillation peaks of bulk longitudinal magnetoresistivity shift at high fields,due to their coupling to the oscillations of the surface Fermi-arc states.Our work provides a thermal control mechanism for the manipulation of quantum states in Dirac semimetal Cd_(3)As_(2) at high temperatures,via their carrier density.
基金the National Science Foundation of China(Nos.22090043 and 22161014)Guangxi Natural Science Foundation(Nos.2019GXNSFGA245006 and 2020GXNSFAA297220)the Foundation of Guilin University of Technology(No.GUTQDJJ2018115)for the financial support。
文摘A new bismuth-based halide double perovskite Cs_(2)KBiCl_(6) was isolated successfully through solid-state reactions and investigated using X-ray and neutron diffraction.Rather than an ordered structure,the crystal structure consists of shifted Cs,K,Bi,and Cl sites from the ideal positions with fractional occupancy in compensation,leading to variable local coordination of Cs^(+)ions,as revealed by^(133)Cs solid-state nuclear magnetic resonance spectroscopy.Cs_(2)KBiCl_(6) displays volume hysteresis at 5-298 K range upon heating and cooling.The Cs_(2)KBiCl_(6) has a direct bandgap of 3.35(2)eV and red-shift luminescence of around 600 nm upon Mn doping compared with the Na analogue.The stabilization of disordered structure in Cs_(2)KBiCl_(6) is related to two factors including the large-sized K^(+)cation which prefers to coordinate with more than six Cl^(-),and the Bi^(3+)with 6s^(2) lone pair which has a preference for a local asymmetric environment.These findings could have general application and help to understand the structure and property of halide perovskites.
基金the Shanghai Science and Technology Innovation Action Plan(Grant No.21JC1402000)the National Natural Science Foundation of China(Grant No.12004405)+3 种基金the State Key Laboratory of Functional Materials for Informatics(Grant No.SKL2022)the Double FirstClass Initiative Fund of ShanghaiTech University,the Analytical Instrumentation Center(Grant No.SPST-AIC10112914)SPST,and ShanghaiTech Universitythe State Key Laboratory of Surface Physics and Department of Physics of Fudan University(Grant No.KF2022_13)。
文摘The van der Waals(vdW)MnSb4Te7is a newly synthesized antiferromagnetic(AFM)topological insulator hosting a robust axion insulator state irrelative to the specific spin structure.However,the intrinsic hole doped character of MnSb_4Te_7makes the Fermi level far away from the Dirac point of about 180 meV,which is unfavorable for the exploration of exotic topological properties such as the quantum anomalous Hall effect(QAHE).To shift up the Fermi level close to the Dirac point,the strategy of partially replacing Sb with Bi as Mn(Sb_(1-x)Bi_(x))_(4)Te_(7)was tried and the magnetotransport properties,in particular,the anomalous Hall effect,were measured and analyzed.Through the electron doping,the anomalous Hall conductanceσAH changes from negative to positive between x=0.3 and 0.5,indicative of a possible topological transition.Besides,a charge neutrality point(CNP)also appears between x=0.6 and 0.7.The results would be instructive for further understanding the interplay between nontrivial topological states and the magnetism,as well as for the exploration of exotic topological properties.
基金supported by the National Natural Science Foundation of China (Grant Nos. 92065201, 11774223, and U2032213)the Open Project of Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education)+3 种基金Shanghai Jiao Tong University (Grant No. 2020–04)supported by the Shenzhen Peacock Team Plan (Grant No. KQTD20170809110344233)Bureau of Industry and Information Technology of Shenzhen through the Graphene Manufacturing Innovation Center (Grant No. 201901161514)support from Analytical Instrumentation Center, SPST, Shanghai Tech University (Grant No. SPST-AIC10112914)
文摘We report the nontrivial topological states in an intrinsic type-Ⅱ superconductor BaSn_(5)(T_(c)∼4.4 K)probed by measuring the magnetization,specific heat,de Haas–van Alphen(dHvA)effect,and by performing first-principles calculations.The first-principles calculations reveal a topological nodal ring structure centered at the H point in the k_(z)=πplane of the Brillouin zone,which could be gapped by spin-orbit coupling(SOC),yielding relatively small gaps below and above the Fermi level of about 0.04 eV and 0.14 eV,respectively.The SOC also results in a pair of Dirac points along theΓ–A direction,located at∼0.2 eV above the Fermi level.The analysis of the dHvA quantum oscillations supports the calculations by revealing a nontrivial Berry phase originating from the hole and electron pockets related to the bands forming the Dirac cones.Thus,our study provides an excellent avenue for investigating the interplay between superconductivity and nontrivial topological states.
基金Supported by the National Natural Science Foundation of China(Grant No.11874264)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDA18000000)+3 种基金the Starting Grant of Shanghai Tech University,the Shenzhen Peacock Team Plan(Grant No.KQTD20170809110344233)the Bureau of Industry and Information Technology of Shenzhen through the Graphene Manufacturing Innovation Center(Grant No.201901161514)the Key Scientific Research Projects of Higher Institutions in Henan Province(19A140018)Analytical Instrumentation Center,SPST,Shanghai Tech University(Grant No.SPST-AIC10112914).
文摘Characterization of Fermi surface of the BaSn3 superconductor(Tc~ 4.4K)by de Haas–van Alphen(dHvA)effect measurement reveals its non-trivial topological properties.Analysis of non-zero Berry phase is supported by the ab initio calculations,which reveals a type-II Dirac point setting and tilting along the high symmetric K–H line of the Brillouin zone,about 0.13 eV above the Fermi level,and other two type-I Dirac points on the high symmetric Г–A direction,but slightly far below the Fermi level.The results demonstrate BaSn3 as an excellent example hosting multiple Dirac fermions and an outstanding platform for studying the interplay between nontrivial topological states and superconductivity.
基金supported by the National Natural Science Foundation of China(Grant No.12104231,12364051,22303031)Innovation Training Program for College Students in Nanjing Forestry University(Grant No.202410298184Y)。
文摘The enduring enigma surrounding the near-infrared(NIR)emission of Mn^(2+)continues to ignite intense academic discussions.Numerous hypotheses have emerged from extensive research endeavors to explain this phenomenon,such as the formation of Mn^(2+)-Mn^(2+)ion pairs,Mn^(2+)occupying cubically coordinated sites,as well as conjectures positing the involvement of Mn3+oxidized from Mn^(2+)or defects.Despite these diverse and valuable insights,none of the hypotheses have yet achieved broad consensus.In this study,we have observed prolonged fluorescence lifetimes(~10ms)for the NIR emissions of Mn^(2+)ions,hinting at these ions occupying the high-symmetry octahedral sites inherent to the garnet lattice.This inference is supported by the corroborating results from X-ray absorption fine structure analysis and first-principles calculations.The intense crystal field of octahedral sites,similar to that of AlO6,facilitates the splitting of d-d energy levels,thereby inducing a red-shift in the emission spectrum to the NIR region due to the transition ^(4)T_(1)(4G)→ ^(6)A_(n)(6S)of isolated Mn^(2+).Our findings not only offer a plausible rationale for the NIR emission exhibited by other Mn^(2+)-activated garnet phosphors but also pave a definitive route towards understanding the fundamental mechanisms responsible for the NIR emission of Mn^(2+)ions.
基金supported by the National Science Fund for Distinguished Young Scholars of China(32225034)the National Natural Science Foundation of China(22308028)+1 种基金the Fundamental Research Funds for the Central Universities(JCYJ202501)the Young Elite Scientists Sponsorship Program by CAST(YESS20240208).
文摘Materials exhibiting time-dependent phosphorescence color(TDPC)are attractive,but generally suffer from complex preparation processes and low-color contrast.Herein,molecular aggregation regulation of 1-pyrenecarboxylic acid(PyC)in the konjac glucomannan(KGM)matrix is proposed to realize high-contrast TDPC.The steric hindrance of KGM enables isolated state,carboxyl dimer,andπ-stacking-induced multimers of PyC with different phosphorescence wavelengths and lifetimes to coexist,leading to a typical TDPC evolution from red to blue-green.The TDPC shows remarkable phosphorescence wavelength shift up to 182 nm and phosphorescence lifetime up to 788.43 ms,readily recognized by the naked eye.In addition,KGM,an edible natural polysaccharide,displays decent rheological properties suitable for screen printing,film casting,and 3D printing,making PyC-KGM an eco-friendly tool for multi-dimensional information security applications.The work provides a simple yet efficient method for high-contrast TDPC materials and affords a promising material for high-level dynamic information encryption and anti-counterfeiting.
文摘In two-dimensional van der Waals magnetic materials,the interplay between magnetism and electron correlation can give rise to new ground states and lead to novel transport and optical properties.A fundamental question in these materials is how the electron correlation manifests and interacts with the magnetic orders.In this study,we demonstrate that the recently discovered 2D antiferromagnetic material,CrSBr is a Mott insulator,through the combined use of resonant and temperature-dependent angle-resolved photoemission spectroscopy techniques,supplemented by dynamical mean-field theory analysis.Intriguingly,we found that as the system transitions from the antiferromagnetic to the paramagnetic phases,its Mott bands undergo a reconfiguration,and a coherent-incoherent crossover,driven by the dissolution of the magnetic order.Our findings reveal a distinctive evolution of band structure associated with magnetic phase transitions,shedding light on the investigation of the intricate interplay between correlation and magnetic orders in strongly correlated van der Waals magnetic materials.
文摘Impedance matching is important for achieving high-efficiency microwave absorbers. The high conductivity of dielectric loss materials such as pure metals and carbon nanomaterials generally results in poor absorption owing to the low impedance matching between the absorbers and air. Carbon nanostructures are very promising candidates for high-efficiency absorption because of their attractive features including low density, high surface area, and good stability. Herein, a new strategy is proposed to improve the impedance matching of dielectric loss materials using electrospun carbon nanofibers as an example. The carbon nanofibers are coated with specifically designed gradient multilayer nanofilms with gradually increasing electroconductibility synthesized by doping ZnO with different A1203 content （AZO） by atomic layer deposition. The gradient nanofilms are composed of five layers of dielectric films, namely, pure A1203, AZO （5：1, the pulse cycle ratio of ZnO to A1203）, pure ZnO, AZO （10：1）, and AZO （20：1）. The versatile gradient films serve as intermediate layers to tune the impedance matching between air and the carbon nanofiber surfaces. Therefore, the carbon nanofibers coated with gradient films of rationally selected thicknesses exhibit remarkably enhanced microwave absorption performance, and the optimal reflection loss reaches -58.5 dB at 16.2 GHz with a thickness of only 1.8 mm. This work can help further understand the contribution of impedance matching to microwave absorption. Our strategy is general and can be applied to improve the absorption properties of other dielectric loss materials and even for applications in other fields.
基金This work was financially supported by the National Natural Science Foundation of China(No.52172096)the Foundation of CNU(No.0092255073).
文摘Immune therapy based on programmed death-ligand 1(PD-L1)is widely used to treat human tumors.The current strategies to improve immune checkpoint blockade therapy fail in rescuing increased expression of PD-L1 in tumor issues.Here,we for the first time synthesized the metal-organic framework(MOF)nanocrystals of rare-earth element dysprosium(Dy)coordinated with tetrakis(4-carboxyphenyl)porphyrin(TCPP),which show well-defined two-dimensional morphologies.The MOF nanocrystals of Dy-TCPP could apparently reduce PD-L1 expression in tumor cells both in vitro and in vivo,and therefore display effective tumor treatment through immune therapy without any immune checkpoint inhibitor drugs.Considering the sensitivity of TCPP ligand toward ultrasound,the prepared Dy-TCPP can also realize sonodynamic therapy(SDT)besides immune therapy.In addition,the Dy-TCPP nanocrystals can efficiently obtain T_(2)-weight magnetic resonance imaging(MRI)of tumor sites.Our study provides the Dy-TCPP nanocrystals as promising diagnostic MRI-guided platforms for the combined treatment on tumors with SDT and immune therapy.Moreover,this strategy succeeds in reducing the elevated expression of PD-L1 in tumor cells,which might serve as a novel avenue for tumor immunotherapy in future.
基金supported by the Research Project of the Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education(2017005)the National Natural Science Foundation of China(Nos.51571072 and 51871078)Heilongjiang Science Foundation(No.E2018028).
文摘The electrocatalytic hydrogen evolution reaction(HER)is one of the most promising ways for low-cost hydrogen production in the future.In this work,hetero S atoms were introduced into the MoO2 to enhance the catalytic activity by simultaneously adjusting electron structure,engineering lattice defect,and increasing oxygen vacancies.And the S doped MoO2 nanosheets with proper S doping amount show the enhanced performance for HER.The optimized catalyst shows a small onset overpotential as low as 120 mV,a low overpotential of 176 mV at the current density of 10 mA/cm^2 which is decreased 166 mV compared to that of the pristine MoO2 nanosheets,a low Tafel slope of 57 mV/decade,and a high turnover frequency of 0.13 H2/s per active site at 150 mV.This finding proposes an effective strategy to prepare nonprecious metal oxide catalyst for enhancing HER performance by rationally doping hetero atoms.
基金the National Natural Science Foundation of China(Nos.51871078 and 52071119)Heilongjiang Science Foundation(No.E201808).
文摘The hydrogen evolution reaction(HER)of molybdenum disulfide(MoS_(2))is limited in alkaline and acid solution because the active sites are on the finite edge with extended basal plane remaining inert.Herein,we activated the interfacial S sites by coupling with Ru nanoparticles on the inert basal plane of MoS_(2)nanosheets.The density functional theory(DFT)calculation and experimental results show that the interfacial S electronic structure was modulated.And the results of∆G H*demonstrate that the adsorption of H on the MoS_(2)was also optimized.With the advantage of interfacial S sites activation,the Ru-MoS_(2)needs only overpotential of 110 and 98 mV to achieve 10 mA·cm^(–2)in both 0.5 M H_(2)SO_(4)and ^(1) M KOH solution,respectively.This strategy paves a new way for activating the basal plane of other transition metal sulfide electrocatalysts for improving the HER performance.
基金supports from the National Key Research and Development Program of China(2020YFA0211300)National Science Foundation of China(grant Nos.62225501,12027807)+1 种基金Bejing Natural Science Foundation(grant Nos.Z180011)High-performance Computing Platform of Peking University.
文摘Phonon-assisted photon upconversion(UPC)is an anti-Stokes process in which incident photons achieve higher energy emission by absorbing phonons.This letter studies phonon-assisted UPC in twisted 2D semiconductors,in which an inverted contrast between UPC and conventional photoluminescence(PL)of WSe2 twisted bilayer is emergent.A 4-fold UPC enhancement is achieved in 5.5°twisted bilayer while PL weakens by half.Reduced interlayer exciton conversion efficiency driven by lattice relaxation,along with enhanced pump efficiency resulting from spectral redshift,lead to the rotation-angle-dependent UPC enhancement.The counterintuitive phenomenon provides a novel insight into a unique way that twisted angle affects UPC and light-matter interactions in 2D semiconductors.Furthermore,the UPC enhancement platform with various superimposable means offers an effective method for lighting bilayers and expanding the application prospect of 2D stacked van der Waals devices.
