LaFe_(11.8)Si_(1.2)/10 wt%Ce_(60)Co_(40) composites were prepared by spark plasma sintering and subsequent diffusion annealing.A novel core-shell structure is observed with the LaFe11.8Si1.2 particles as the core and ...LaFe_(11.8)Si_(1.2)/10 wt%Ce_(60)Co_(40) composites were prepared by spark plasma sintering and subsequent diffusion annealing.A novel core-shell structure is observed with the LaFe11.8Si1.2 particles as the core and the(La,Ce)_(2)(Fe,Co,Si)_(17)(2:17)phase as the shell.As diffusion annealing time(t_(a))increases,this core-shell structure is replaced by the formation of the(La,Ce)_(1)(Fe,Co,Si)_(13) phase.Annealing at 1323 K for 12 h results in samples with(-ΔSM)^(max) of 9.30 J/(kg·K)(Δμ0H=2 T),good mechanical properties((σbc)^(max)=402 MPa,ε=4.21%)and thermal conductivity of 8.7 W/(m·K).Thus,bulk composites with excellent comprehensive properties for magnetic refrigeration are obtained in this work.展开更多
Rare earth elements(lanthanide and yttrium,abbreviated as REY) provide important support for national security,energy production,environmental protection and economic growth.In recent years,many studies have shown tha...Rare earth elements(lanthanide and yttrium,abbreviated as REY) provide important support for national security,energy production,environmental protection and economic growth.In recent years,many studies have shown that the content of REY in some coal or coal by-products is close to or even higher than that in traditional REY ore,which makes coal a potential source of REY.This study took the No.17 coal of Panzhou mining area in Liupanshui coal field as the research object,and the content and occurrence modes of REY in raw coal and 7 density fraction samples were studied.The results show that the content of REY in the raw coal reaches 220.67 μg/g,which is significantly higher than the average REY content in the world coal and Chinese coal as reported in the literature.Gravity separation has a certain pre-enrichment effect on REY and the fraction sample> 1.8 g/cm~3 has the highest REY of 426.27 μg/g(equal to rare earth oxide 0.1%).Study on correlation between REY and ash yields reveals that the organic affinity of the light rare earth is higher than that of the medium rare earth and the heavy rare earth.As shown by X-ray diffraction(XRD) and X-ray flouresence spectroscopy(XRF),the major minerals in coal are kaolinite,quartz and calcite,and the content of REY in coal is significantly related to Al,Si and kaolinite,which implies that REY occur mainly in kaolinite.Laser ablation inductively coupled plasma mass spectroscopy(LA-ICP-MS) was adopted to determine chemical composition of micro-zone in kaolinite in coal and the results show that there is no obvious correlation between REY and the contents of Al and Si.This indicates that the REY occur probably in the form of adsorption.The research results provide a scientific reference for the potential extraction of the associated REY in the coal.展开更多
Prehistoric projectile weapons are crucial for understanding the hunting behavior,survival strategies,and subsistence patterns of prehistoric humans.Arrowheads were the primary prehistoric projectile weapon,and here w...Prehistoric projectile weapons are crucial for understanding the hunting behavior,survival strategies,and subsistence patterns of prehistoric humans.Arrowheads were the primary prehistoric projectile weapon,and here we review the spatiotemporal distribution and changes in the morphology,quantity,and materials composition of arrowheads in the northern regions of China from the Middle and Upper Paleolithic periods to the Bronze Age,together with the factors that influenced these changes.The results reveal that primitive stone arrowheads appeared sporadically in the Middle Paleolithic period.Additionally,the“broad spectrum revolution”and microblade technology during the Upper Paleolithic promoted the regional-scale diffusion of broad and thick stone arrowheads in northern China.During the Neolithic period,relatively narrow and thin stone and bone arrowheads spread rapidly across the entire Yellow River Basin and most of northeastern China.The dominance of these two types of arrowheads alternated,during the period of 7000–5000 yr BP,the number of arrowheads peaked,possibly closely related to changes in the role of hunting(fishing and hunting)and gathering in the subsistence economy,human population size,and the emergence and development of a grinding technology.During the Bronze Age,a significant number of bronze arrowheads appeared,and the total number of arrowheads increased again,and their distribution expanded to northwestern China.The emergence of a bronze smelting technology and inter-group conflicts may have been the primary factors influencing this trend.Our results demonstrate that arrowheads were always an essential component of prehistoric tool kits.Due to technological developments in subsistence strategies,the morphology,function,and popularity of arrowheads underwent substantial changes during different periods.Therefore,a comprehensive study of prehistoric arrowheads can help better understand the subsistence patterns and processes of economic and societal development of prehistoric humans.展开更多
Rheumatoid arthritis(RA)is a relatively common inflammatory disease that affects the synovial tissue,eventually results in joints destruction and even long-term disability.Although Janus kinase inhibitors(Jakinibs)sho...Rheumatoid arthritis(RA)is a relatively common inflammatory disease that affects the synovial tissue,eventually results in joints destruction and even long-term disability.Although Janus kinase inhibitors(Jakinibs)show a rapid efficacy and are becoming the most successful agents in RA therapy,high dosing at frequent interval and severe toxicities cannot be avoided.Here,we developed a new type of fully compatible nanocarriers based on recombinant chimeric proteins with outstanding controlled release of upadacitinib.In addition,the fluorescent protein component of the nanocarriers enabled noninvasive fluorescence imaging of RA lesions,thus allowing real-time detection of RA therapy.Using rat models,the nanotherapeutic is shown to be superior to free upadacitinib,as indicated by extended circulation time and sustained bioefficacy.Strikingly,this nanosystem possesses an ultralong half-life of 45 h and a bioavailability of 4-times higher than pristine upadacitinib,thus extending the dosing interval from one day to 2 weeks.Side effects such as over-immunosuppression and leukocyte levels reduction were significantly mitigated.This smart strategy boosts efficacy,safety and visuality of Jakinibs in RA therapy,and potently enables customized designs of nanoplatforms for other therapeutics.展开更多
Functional proteins are the most versatile macromolecules.They can be obtained by extraction from natural sources or by genetic engineering technologies.The outstanding selectivity,specificity,binding activity,and bio...Functional proteins are the most versatile macromolecules.They can be obtained by extraction from natural sources or by genetic engineering technologies.The outstanding selectivity,specificity,binding activity,and biocompatibility endow engineered proteins with outstanding performance for disease therapy.Nevertheless,their stability is dramatically impaired in blood circulation,hindering clinical translations.Thus,many strategies have been developed to improve the stability,efficacy,bioavailability,and productivity of therapeutic proteins for clinical applications.In this review,we summarize the recent progress in the fabrication and application of therapeutic proteins.We first introduce various strategies for improving therapeutic efficacy via bioengineering and nanoassembly.Furthermore,we highlight their diverse applications as growth factors,nanovaccines,antibody-based drugs,bioimaging molecules,and cytokine receptor antagonists.Finally,a summary and perspective for the future development of therapeutic proteins are presented.展开更多
Two-dimensional(2D) periodical Au and indium tin oxide(ITO) nanocomposite arrays have been fabricated based on a self-assembled nanosphere lithography technique. A button-shaped Au nanoparticle was formed on each holl...Two-dimensional(2D) periodical Au and indium tin oxide(ITO) nanocomposite arrays have been fabricated based on a self-assembled nanosphere lithography technique. A button-shaped Au nanoparticle was formed on each hollow hemisphere-shaped ITO shell. Importantly, the underlying formation mechanism during the thermal treatment has been thoroughly explored by comparing structures resulting from different deposition conditions in detail. Compared to the Au nanoparticle arrays without ITO shells, the Au/ITO nanocomposite arrays showed a stronger localized surface plasmon resonance effect and higher absorption in the near-infrared(NIR) region, benefiting from the free-electron interaction enhancement between Au and ITO. The nonlinear optical properties were investigated using a modified femtosecond intensity-scan system, and the results demonstrated Au/ITO nanocomposite arrays with a remarkable two-photon absorption saturation effect for femtosecond pulses at 1030 nm. The versatile NIR optical responses indicate the great potential of the elaborately prepared 2D periodical Au/ITO nanocomposite arrays in many applications such as solar cells, photocatalysis,and novel nano optoelectronic devices.展开更多
Questions hovering over the modulation of bandgap size and excitonic effect on nonlinear absorption in twodimensional transition metal dichalcogenides (TMDCs) have restricted their application in micro/nano optical mo...Questions hovering over the modulation of bandgap size and excitonic effect on nonlinear absorption in twodimensional transition metal dichalcogenides (TMDCs) have restricted their application in micro/nano optical modulator, optical switching, and beam shaping devices. Here, degenerate two-photon absorption (TPA) in the near-infrared region was studied experimentally in mechanically exfoliated MoS2 from single layer to multilayer. The layer-dependent TPA coefficients were significantly modulated by the detuning of the excitonic dark state (2p). The shift of the quasiparticle bandgap and the decreasing of exciton binding energy with layers were deduced, combined with the non-hydrogen model of excitons in TMDCs and the scaling rule of semiconductors. Our work clearly demonstrates the layer modulation of nonlinear absorption in TMDCs and provides support for layer-dependent nonlinear optical devices, such as optical limiters and optical switches.展开更多
In this work, a series of new metal phosphonates were hydrothermally synthesized and structurally characterized based on m-xylylenediphosphonic acids(H4L), including[M(H2L)(bpy)](M = Mn 1, Co 2), [MH2L)(phen)](M = Co3...In this work, a series of new metal phosphonates were hydrothermally synthesized and structurally characterized based on m-xylylenediphosphonic acids(H4L), including[M(H2L)(bpy)](M = Mn 1, Co 2), [MH2L)(phen)](M = Co3, Cu 4), and [Cu2(H2L)2(bpy00)2] 5(bpy = 2,20-bipyridine,phen = 1,10-phenanthroline, bpy00= 4,40-dimethyl-2,20-bipyridine). X-ray diffraction indicated that compounds 1 and2 were isomorphic. Complexes 3 and 4 were shown to crystallize in different space groups but had similar crystallographic units. In the complexes, H4 L was seen to partially deprotonate to afford H2L2-. The H2L2-ligands in 1–4functioned as tetradentate ligands with each phosphonate group adopting bidentate coordination mode with two M centers to generate a 2D layer. In addition, the H2L2-anions in5 functioned as tridentate ligands with one phosphonate group adopting the bidentate mode and another phosphonate group adopti ng the monodentate mode, thus linking three Cu atoms to provide a 1D chain. The IR and thermal stabilities of these compounds were subsequently examined.展开更多
基金Project supported by the Guangdong Basic and Applied Basic Research Foundation(2022A1515012578,2019A1515010970)the Guangzhou Municipal Science and Technology Project(201904010030)+2 种基金the National Natural Science Foundation of China(51874143,52066001)the Special Project of Foshan Scientific and Technological Innovation Team(2030032000171,2120001010823)partially supported by the National Research Foundation,Prime Minister’s Office,Singapore under its Campus of ResearchExcellence and Technological Enterprise(CREATE)programme。
文摘LaFe_(11.8)Si_(1.2)/10 wt%Ce_(60)Co_(40) composites were prepared by spark plasma sintering and subsequent diffusion annealing.A novel core-shell structure is observed with the LaFe11.8Si1.2 particles as the core and the(La,Ce)_(2)(Fe,Co,Si)_(17)(2:17)phase as the shell.As diffusion annealing time(t_(a))increases,this core-shell structure is replaced by the formation of the(La,Ce)_(1)(Fe,Co,Si)_(13) phase.Annealing at 1323 K for 12 h results in samples with(-ΔSM)^(max) of 9.30 J/(kg·K)(Δμ0H=2 T),good mechanical properties((σbc)^(max)=402 MPa,ε=4.21%)and thermal conductivity of 8.7 W/(m·K).Thus,bulk composites with excellent comprehensive properties for magnetic refrigeration are obtained in this work.
基金Project supported by National Natural Science Foundation of China (51964009,41802190)。
文摘Rare earth elements(lanthanide and yttrium,abbreviated as REY) provide important support for national security,energy production,environmental protection and economic growth.In recent years,many studies have shown that the content of REY in some coal or coal by-products is close to or even higher than that in traditional REY ore,which makes coal a potential source of REY.This study took the No.17 coal of Panzhou mining area in Liupanshui coal field as the research object,and the content and occurrence modes of REY in raw coal and 7 density fraction samples were studied.The results show that the content of REY in the raw coal reaches 220.67 μg/g,which is significantly higher than the average REY content in the world coal and Chinese coal as reported in the literature.Gravity separation has a certain pre-enrichment effect on REY and the fraction sample> 1.8 g/cm~3 has the highest REY of 426.27 μg/g(equal to rare earth oxide 0.1%).Study on correlation between REY and ash yields reveals that the organic affinity of the light rare earth is higher than that of the medium rare earth and the heavy rare earth.As shown by X-ray diffraction(XRD) and X-ray flouresence spectroscopy(XRF),the major minerals in coal are kaolinite,quartz and calcite,and the content of REY in coal is significantly related to Al,Si and kaolinite,which implies that REY occur mainly in kaolinite.Laser ablation inductively coupled plasma mass spectroscopy(LA-ICP-MS) was adopted to determine chemical composition of micro-zone in kaolinite in coal and the results show that there is no obvious correlation between REY and the contents of Al and Si.This indicates that the REY occur probably in the form of adsorption.The research results provide a scientific reference for the potential extraction of the associated REY in the coal.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research Program(STEP)(Grant No.2019QZKK0601-02)the Fundamental Research Funds for the Central Universities(Grant No.lzujbky-2021-ct03).
文摘Prehistoric projectile weapons are crucial for understanding the hunting behavior,survival strategies,and subsistence patterns of prehistoric humans.Arrowheads were the primary prehistoric projectile weapon,and here we review the spatiotemporal distribution and changes in the morphology,quantity,and materials composition of arrowheads in the northern regions of China from the Middle and Upper Paleolithic periods to the Bronze Age,together with the factors that influenced these changes.The results reveal that primitive stone arrowheads appeared sporadically in the Middle Paleolithic period.Additionally,the“broad spectrum revolution”and microblade technology during the Upper Paleolithic promoted the regional-scale diffusion of broad and thick stone arrowheads in northern China.During the Neolithic period,relatively narrow and thin stone and bone arrowheads spread rapidly across the entire Yellow River Basin and most of northeastern China.The dominance of these two types of arrowheads alternated,during the period of 7000–5000 yr BP,the number of arrowheads peaked,possibly closely related to changes in the role of hunting(fishing and hunting)and gathering in the subsistence economy,human population size,and the emergence and development of a grinding technology.During the Bronze Age,a significant number of bronze arrowheads appeared,and the total number of arrowheads increased again,and their distribution expanded to northwestern China.The emergence of a bronze smelting technology and inter-group conflicts may have been the primary factors influencing this trend.Our results demonstrate that arrowheads were always an essential component of prehistoric tool kits.Due to technological developments in subsistence strategies,the morphology,function,and popularity of arrowheads underwent substantial changes during different periods.Therefore,a comprehensive study of prehistoric arrowheads can help better understand the subsistence patterns and processes of economic and societal development of prehistoric humans.
基金supported by the National Key R&D Program of China(Nos.2022YFA0913200,2021YFF0701800,2022YFF0710000,and 2020YFA0908900)the National Natural Science Foundation of China(Nos.22107097,22020102003,22277064,82272161,and 22125701)+1 种基金Tsinghua University Spring Breeze Fund grant(No.2021Z99CFZ005),and the Youth Innovation Promotion Association of CAS(No.2021226)All animal experiments were conducted in compliance with the Animal Management Rules of the Ministry of Health of the People's Republic of Chinawith the approval of the Institutional Animal Care and Use Committee of the Animal Experiment Center of Jilin University(No.PZPX20180929070).
文摘Rheumatoid arthritis(RA)is a relatively common inflammatory disease that affects the synovial tissue,eventually results in joints destruction and even long-term disability.Although Janus kinase inhibitors(Jakinibs)show a rapid efficacy and are becoming the most successful agents in RA therapy,high dosing at frequent interval and severe toxicities cannot be avoided.Here,we developed a new type of fully compatible nanocarriers based on recombinant chimeric proteins with outstanding controlled release of upadacitinib.In addition,the fluorescent protein component of the nanocarriers enabled noninvasive fluorescence imaging of RA lesions,thus allowing real-time detection of RA therapy.Using rat models,the nanotherapeutic is shown to be superior to free upadacitinib,as indicated by extended circulation time and sustained bioefficacy.Strikingly,this nanosystem possesses an ultralong half-life of 45 h and a bioavailability of 4-times higher than pristine upadacitinib,thus extending the dosing interval from one day to 2 weeks.Side effects such as over-immunosuppression and leukocyte levels reduction were significantly mitigated.This smart strategy boosts efficacy,safety and visuality of Jakinibs in RA therapy,and potently enables customized designs of nanoplatforms for other therapeutics.
基金supported by the National Key Research and Development Program of China(Nos.2020YFA0908900,2018YFA0902600,and 2020YFA0712102)the National Natural Science Foundation of China(Nos.21877104,21834007,22107097,21878258,22020102003,and 22125701)+1 种基金K.C.Wong Education Foundation(No.GJTD-2018-09)the Youth Innovation Promotion Association of the Chinese Academy(CAS,No.2021226).
文摘Functional proteins are the most versatile macromolecules.They can be obtained by extraction from natural sources or by genetic engineering technologies.The outstanding selectivity,specificity,binding activity,and biocompatibility endow engineered proteins with outstanding performance for disease therapy.Nevertheless,their stability is dramatically impaired in blood circulation,hindering clinical translations.Thus,many strategies have been developed to improve the stability,efficacy,bioavailability,and productivity of therapeutic proteins for clinical applications.In this review,we summarize the recent progress in the fabrication and application of therapeutic proteins.We first introduce various strategies for improving therapeutic efficacy via bioengineering and nanoassembly.Furthermore,we highlight their diverse applications as growth factors,nanovaccines,antibody-based drugs,bioimaging molecules,and cytokine receptor antagonists.Finally,a summary and perspective for the future development of therapeutic proteins are presented.
基金Funding.National Natural Science Foundation of China(NSFC)(61308087,61405224,61522510,61675217)Natural Science Foundation of Shanghai(16ZR1440300)+4 种基金China Scholarship Council(CSC)Science Foundation Ireland(SFI)Chinese Academy of Sciences(CAS)(XDB16030700QYZDBSSW-JSC041)Science and Technology Commission of Shanghai Municipality(STCSM)(17XD1403900)
文摘Two-dimensional(2D) periodical Au and indium tin oxide(ITO) nanocomposite arrays have been fabricated based on a self-assembled nanosphere lithography technique. A button-shaped Au nanoparticle was formed on each hollow hemisphere-shaped ITO shell. Importantly, the underlying formation mechanism during the thermal treatment has been thoroughly explored by comparing structures resulting from different deposition conditions in detail. Compared to the Au nanoparticle arrays without ITO shells, the Au/ITO nanocomposite arrays showed a stronger localized surface plasmon resonance effect and higher absorption in the near-infrared(NIR) region, benefiting from the free-electron interaction enhancement between Au and ITO. The nonlinear optical properties were investigated using a modified femtosecond intensity-scan system, and the results demonstrated Au/ITO nanocomposite arrays with a remarkable two-photon absorption saturation effect for femtosecond pulses at 1030 nm. The versatile NIR optical responses indicate the great potential of the elaborately prepared 2D periodical Au/ITO nanocomposite arrays in many applications such as solar cells, photocatalysis,and novel nano optoelectronic devices.
基金Strategic Priority Research Program of CAS(XDB16030700)Program of Shanghai Academic Research Leader(17XD1403900)+7 种基金Natural Science Foundation of Shanghai(18ZR1444700)Youth Innovation Promotion Association of the Chinese Academy of SciencesNational Natural Science Foundation of China(NSFC)(11874370,61675217,61875213)Shanghai Rising-Star Program(19QA1410000)CAS Interdisciplinary Innovation Team and National Natural Science Foundation of China(11535010)CAS Center for Excellence in Ultra-Intense Laser ScienceKey Research Program of Frontier Science of CAS(QYZDB-SSW-JSC041)President’s International Fellowship Initiative(PIFI)of CAS(2017VTA0010,2017VTB0006,2018VTB0007)
文摘Questions hovering over the modulation of bandgap size and excitonic effect on nonlinear absorption in twodimensional transition metal dichalcogenides (TMDCs) have restricted their application in micro/nano optical modulator, optical switching, and beam shaping devices. Here, degenerate two-photon absorption (TPA) in the near-infrared region was studied experimentally in mechanically exfoliated MoS2 from single layer to multilayer. The layer-dependent TPA coefficients were significantly modulated by the detuning of the excitonic dark state (2p). The shift of the quasiparticle bandgap and the decreasing of exciton binding energy with layers were deduced, combined with the non-hydrogen model of excitons in TMDCs and the scaling rule of semiconductors. Our work clearly demonstrates the layer modulation of nonlinear absorption in TMDCs and provides support for layer-dependent nonlinear optical devices, such as optical limiters and optical switches.
基金supported by the National Natural Science Foundation of China(51372125,21176128 and 21203106)the Natural Science Foundation of Shandong Province,China(BS2010CL019,ZR2011BL015)
文摘In this work, a series of new metal phosphonates were hydrothermally synthesized and structurally characterized based on m-xylylenediphosphonic acids(H4L), including[M(H2L)(bpy)](M = Mn 1, Co 2), [MH2L)(phen)](M = Co3, Cu 4), and [Cu2(H2L)2(bpy00)2] 5(bpy = 2,20-bipyridine,phen = 1,10-phenanthroline, bpy00= 4,40-dimethyl-2,20-bipyridine). X-ray diffraction indicated that compounds 1 and2 were isomorphic. Complexes 3 and 4 were shown to crystallize in different space groups but had similar crystallographic units. In the complexes, H4 L was seen to partially deprotonate to afford H2L2-. The H2L2-ligands in 1–4functioned as tetradentate ligands with each phosphonate group adopting bidentate coordination mode with two M centers to generate a 2D layer. In addition, the H2L2-anions in5 functioned as tridentate ligands with one phosphonate group adopting the bidentate mode and another phosphonate group adopti ng the monodentate mode, thus linking three Cu atoms to provide a 1D chain. The IR and thermal stabilities of these compounds were subsequently examined.