Inspired by molecular catalysts,researchers developed atomically precise nitrogen-coordinated single or dual metal sites imbedded in graphitized carbon(M-N-C)to fully utilize metallic sites for 02activation.These cata...Inspired by molecular catalysts,researchers developed atomically precise nitrogen-coordinated single or dual metal sites imbedded in graphitized carbon(M-N-C)to fully utilize metallic sites for 02activation.These catalysts performed remarkably well in the electrocatalytic oxygen reduction reaction(ORR)due to their distinct coordination and electrical structures,Nonetheless,their maximum efficacy in practical applications has yet to be achieved.This agenda identifies tailoring the coordination environment,spin states,intersite distance,and metal-metal interaction as innovative approaches to regulate the ORR performance of these catalysts.However,it is necessary to undertake a precise assessment of these methodologies and the knowledge obtained to be implemented in the design of future M-N-C catalysts for ORR.Therefore,this review aims to analyze recent progress in M-N-C ORR catalysts,emphasizing their innovative engineering with aspects such as alteration in intersite distance,metal-metal interaction,coordination environment,and spin states.Additionally,we critically discuss how to logically monitor the atomic structure,local coordination,spin,and electronic states of M-N-C catalysts to modulate their ORR activity.We have also highlighted the challenges associated with M-N-C catalysts and proposed suggestions for their future design and fabrication.展开更多
Designing highly active and stable electrocatalysts of oxygen evolution reaction(OER)is one of the crucial challenges.In this study,a novel OER electrocatalyst,NiFe-MIL-53 modified with ultra-low rhodium(Rh@NiFe-MIL-5...Designing highly active and stable electrocatalysts of oxygen evolution reaction(OER)is one of the crucial challenges.In this study,a novel OER electrocatalyst,NiFe-MIL-53 modified with ultra-low rhodium(Rh@NiFe-MIL-53),is successfully prepared via the hydrothermal method.In-situ Raman spectroscopy and electrochemical impedance spectroscopy reveal that the doped Rh accelerates the phase transformation of NiFe-MIL-53 and the in-situ formed Rh@NiFeOOH is the actual active species.More importantly,the enhanced reversibility of electrochemical reconstruction between NiFeOOH and NiFe(OH)_(2)after doping Rh is beneficial for improving the electrochemical stability of the catalyst.X-ray photoelectron spectroscopy spectra show the strong electronic interaction between single-atom Rh and Ni/Fe in Rh@NiFeOOH.Furthermore,theoretical calculations confirm that the integration of single-atom Rh into the NiFeOOH successfully reduces the band gap,regulates the d-band center(εd),accelerates the charge transfer,and optimizes the adsorption behavior of oxygen-containing intermediates,thereby lowering the energy barrier of rate-determining steps.Consequently,the optimized Rh@NiFe-MIL-53 exhibits excellent OER activity(240 mV)with a small Tafel slope of 48.2 mV dec^(-1)and long-term durability(over1270 h at 10 m A cm^(-2)and 110 h at 200 mA cm^(-2)).This work presents a new perspective on designing highly efficient OER electrocatalysts.展开更多
Lithium-ion capacitors(LICs)are becoming important electrochemical energy storage systems due to their great potential to bridge the gap between supercapacitors and lithium-ion batteries.However,capacity lopsidedness ...Lithium-ion capacitors(LICs)are becoming important electrochemical energy storage systems due to their great potential to bridge the gap between supercapacitors and lithium-ion batteries.However,capacity lopsidedness and low output voltage greatly hinder the realization of high-energy-density LICs.Herein,a strategy of balancing capacity towards fastest dynamics is proposed to enable high-voltage LICs.Through electrochemical prelithiation of Nb_(2)C to be 1.1 V with 165 mAh g^(-1),Nb_(2)C//LiFePO_(4) LICs show a broadened potential window from 3.0 to 4.2 V and an according high energy density of 420 Wh kg^(-1).Moreover,the underlying mechanism between prelithiation and high voltage is disclosed by electrochemical dynamic analysis.Prelithiation declines the Nb_(2)C anode potential that facilitates electron transmission in the interlayer of two-dimensional Nb_(2)C MXene.This effect induces small drive force for Li^(+)ions deposition and hence weakens the repulsive force from adsorbed ions on the electrode surface.Benefiting from even more Li^(+)ions deposition,a higher voltage is eventually delivered.In addition,prelithiation significantly increases Coulomb efficiency of the 1st cycle from 74%to 90%,which is crucial to commercial application of LICs.展开更多
Transition metal chalcogenides will be in situ transformed into metal oxyhydroxides during oxygen evolution reaction(OER) process in alkaline medium.However,most of these compounds only undergo surface reconstruction ...Transition metal chalcogenides will be in situ transformed into metal oxyhydroxides during oxygen evolution reaction(OER) process in alkaline medium.However,most of these compounds only undergo surface reconstruction under operating conditions,which contains a large percentage of inactive atoms in the core,thus limiting the exposure of the active sites.Here,we synthesize a Ni-Mo-Se precatalyst with three-dimensional hierarchical structure and develop a facile on-site electrochemical activation strategy for achieving deep reconstruction of the precatalyst.Using the combination of multiple spectroscopic characterizations and high resolution electron microscopy techniques,we unravel that the Ni-Mo-Se precatalyst is deeply reconstructed into γ-NiOOH with co-leaching of Mo and Se after the anodic oxidation.Such flower-like γ-NiOOH is constituted by distorted ultrathin nanosheets with a thickness of ~4.5 nm and contains abundant intercalated species such as water and OH^(-)/CO_(3)^(2-) thus offering a large quantity of accessible active sites.To reach the current density of 10 mA cm^(-2),the derived electrode requires an overpotential of only 244 mV,outperforming almost all the reported analogues.This work highlights the reconstruction chemistry and provides a simple method for the preparation of efficient OER electrocatalyst.展开更多
Tuning surface electron transfer process by sulfur(S)-vacancies engineering is an efficient strategy to develop high-efficient catalysts for electroreduction N_(2) reaction(NRR). Herein, the distinct Sb_(2)S_(3) nanor...Tuning surface electron transfer process by sulfur(S)-vacancies engineering is an efficient strategy to develop high-efficient catalysts for electroreduction N_(2) reaction(NRR). Herein, the distinct Sb_(2)S_(3) nanorods with S-vacancies(Sv-Sb_(2)S_(3)) have been synthesized by a simple twostep method including hydrothermal and hydrogenation in H_(2)/Ar atmosphere, which shows improved performance for NRR with the NH_(3) yield rate of 10.85 μg h^(-1) mgcat^(-1) at-0.4 V vs. RHE, the faradaic efficiency(FE) of 3.75% at -0.3 V vs. RHE and excellent stability for 24 h, largely outperforming bulk Sb_(2)S_(3). X-ray photoelectron spectroscopy(XPS) and density function theory(DFT) calculations demonstrate that the abundant S-vacancies can create an electron-deficient environment and modulate the electron delocalization in Sv-Sb_(2)S_(3), which can not only facilitate the N_(2) molecule adsorption, but also activate the N≡N, resulting in the enhanced performance for NRR.展开更多
Dear Editor,The common marmoset(Callithrix jacchus),a small New World monkey species,is considered an ideal non-human primate model for studying the evolution and neural mechanism of vocal behavior due to their rich c...Dear Editor,The common marmoset(Callithrix jacchus),a small New World monkey species,is considered an ideal non-human primate model for studying the evolution and neural mechanism of vocal behavior due to their rich call repertoire and vocal communication[1-3].Especially,the early vocal development of marmoset monkeys has attracted much attention,because newborn marmosets have been shown to exhibit a vocal development trajectory.Within two months after birth,marmosets'vocalizations undergo dramatic changes from cries to adult-like mature calls,a process that is influenced not only by inner physical maturation but also by parental care and feedback[4].展开更多
lonic-conductive solid-state polymer electrolytes are promising for the development of advanced lithium batteries yet a deeper understanding of their underlying ion-transfer mechanism is needed to improve performance....lonic-conductive solid-state polymer electrolytes are promising for the development of advanced lithium batteries yet a deeper understanding of their underlying ion-transfer mechanism is needed to improve performance.Here we demonstrate the low-enthalpy and high-entropy(LEHE)electrolytes can intrinsically generate remarkably free ions and high mobility,enabling them to efficiently drive lithium-ion storage.The LEHE electrolytes are constructed on the basis of introducing CsPbl_(3)perovskite quantum dots(PQDs)to strengthen PEO@LiTFSI complexes.An extremely stable cycling>1000 h at 0.3 mA cm^(-2)can be delivered by LEHE electrolytes.Also,the as-developed Li|LEHE|LiFePO_(4)cell retains 92.3%of the initial capacity(160.7 mAh g^(-1))after 200 cycles.This cycling stability is ascribed to the suppressed charge concentration gradient leading to free lithium dendrites.It is realized by a dramatic increment in lithium-ion transference number(0.57 vs 0.19)and a significant decline in ion-transfer activation energy(0.14 eV vs 0.22 eV)for LEHE electrolytes comparing with PEO@LiTFSI counterpart.The CsPbl_(3)PQDs promote highly structural disorder by inhibiting crystallization and hence endow polymer electrolytes with low melting enthalpy and high structural entropy,which in turn facilitate long-term cycling stability and excellent rate-capability of lithium-metal batteries.展开更多
The secondary cell wall in mature cotton fibers contains over 90%cellulose with low quantities of xylan and lignin.However,little is known regarding the regulation of secondary cell wall biosynthesis in cotton fibers....The secondary cell wall in mature cotton fibers contains over 90%cellulose with low quantities of xylan and lignin.However,little is known regarding the regulation of secondary cell wall biosynthesis in cotton fibers.In this study,we characterized an R2R3-MYB transcription factor,Gh MYB7,in cotton.Gh MYB7 is expressed at a high level in developing fibers and encodes a MYB protein that is targeted to the cell nucleus and has transcriptional activation activity.Ectopic expression of Gh MYB7 in Arabidopsis resulted in small,curled,dark green leaves and also led to shorter inflorescence stems.A cross-sectional assay of basal stems revealed that cell wall thickness of vessels and interfascicular fibers was higher in transgenic lines overexpressing Gh MYB7 than in the wild type.Constitutive expression of Gh MYB7 in Arabidopsis activated the expression of a suite of secondary cell wall biosynthesis-related genes(including some secondary cell wall-associated transcription factors),leading to the ectopic deposition of cellulose and lignin.The ectopic deposition of secondary cell walls may have been initiated before the cessation of cell expansion.Moreover,Gh MYB7 was capable of binding to the promoter regions of At SND1 and At Ces A4,suggesting that Gh MYB7 may function upstream of NAC transcription factors.Collectively,these findings suggest that Gh MYB7 is a potential transcriptional activator,which may participate in regulating secondary cell wall biosynthesis of cotton fibers.展开更多
The intrinsic activity and durability of oxygen evolution reaction(OER)electrocatalysts are mainly dominated by the surface and interface properties of active materials.Herein,a core-shell heterogeneous structure(NF/N...The intrinsic activity and durability of oxygen evolution reaction(OER)electrocatalysts are mainly dominated by the surface and interface properties of active materials.Herein,a core-shell heterogeneous structure(NF/NiSe@Fe_(2)O_(3))is fabricated via two-step hydrothermal method,which exhibits a low overpotential of 220 mV(or 282 mV)at 10 mA/cm^(2)(or 200 mA/cm^(2)),a small Tafel slope of 36.9 mV/dec,and long-term stability(-230 h)in 1 mol/L KOH for OER.X-ray photoelectron spectroscopy and X-ray absorption spectroscopy reveal the(oxy)hydroxide-rich surface and strong coupling interface between NiSe and Fe_(2)O_(3)via the Fe-Se bond.Density functional theory calculation suggests that the d-band center and electronic state of NiSe@Fe_(2)O_(3)heterojunction are well optimized due to the formation of Fe-Se bond,which is favorable for the enhanced OER activity because of the easy adsorption of oxygen-containing intermediates and desorption of O^(2)in the OER process.In addition,the unique core-shell structure and robust bonding interface are responsible for the good stability for OER.This work provides fundamental insights on the bonding effect that determine the performance of OER electrocatalyst.展开更多
Monitoring physiological signals of the human body can provide extremely important information for sports healthcare,preventing injuries and providing efficient guidance for individual sports.However,the signals relat...Monitoring physiological signals of the human body can provide extremely important information for sports healthcare,preventing injuries and providing efficient guidance for individual sports.However,the signals related to human healthcare involve both subtle and vigorous signals,making it difficult for a sensor to satisfy the full-scale monitoring at the same time.Here,a novel conductive elastomer featuring homogeneously micropyramid-structured PDMS/CNT composite is used to fabricate highperformance piezoresistive sensors by a drop-casting method.Benefiting from the significant increase in the contact area of microstructure during deformation,the flexible sensor presents a broad detection range(up to 185.5 kPa),fast response/recovery time(44/13 ms),ultrahigh sensitivity(242.4 kPa–1)and excellent durability over 8,000 cycles.As a proof of concept,the as-fabricated pressure sensor can be used for body-area sports healthcare,and enable the detection of full-scale pressure distribution.Considering the fabulous sensing performance,the sensor may potentially become promising in personal sports healthcare and telemedicine monitoring.展开更多
In this work,bimetallic NiCoP nanoparticles(NPs)were firstly prepared by a solvothermal method using red phosphorus(RP)as P source,and it was combined with RP nanosheets via a physical grinding process.Investigation i...In this work,bimetallic NiCoP nanoparticles(NPs)were firstly prepared by a solvothermal method using red phosphorus(RP)as P source,and it was combined with RP nanosheets via a physical grinding process.Investigation indicates that NiCoP has better charge transfer ability and faster H_(2)releasing kinetics than the corresponding single metal phosphides alone.6 wt%NiCoP/RP exhibits an excellent H_(2)evolution activity in 20 vol.%triethanol-amine/water solution under a 300W Xe-lamp irradiation,and the corresponding H_(2)production rate is 1535.6μmol·g^(-1)·h^(-1),which is 7.4,3.2 and 2.6 times higher than those of pure RP,6 wt%Co_(2)P/RP and 6 wt%Ni_(2)P/RP,respectively.In addition,we demonstrate that K_(2)HPO_(4)can further enhance the H_(2)evolution kinetics by inducing a new H^(+)reduction path,when appropriate K_(2)HPO_(4)is introduced into the reaction solution.The H_(2)production rate of 6 wt%NiCoP/RP is boosted from 1535.6 to 2793.9μmol·g^(-1)·h^(-1) due to the easier combination between H^(+)and electrons with the assistance of HPO_(4)^(2-).It is 13.4 times higher than that of pure RP.This work demonstrates that bimetallic phosphides with suitable electrolytes can greatly enhance the photocatalytic H_(2)evolution efficiency.展开更多
Polymer solid-state electrolytes(PSSEs)are promising for solving the safety problem of Lithium(Li)metal batteries(LMBs).However,PSSEs with low modulus in nature are prone to be penetrated by lithium dendrites,resultin...Polymer solid-state electrolytes(PSSEs)are promising for solving the safety problem of Lithium(Li)metal batteries(LMBs).However,PSSEs with low modulus in nature are prone to be penetrated by lithium dendrites,resulting in short circuit of LMBs.Here,we design and prepare piezoelectric BaTiO_(3)doped polyacrylonitrile(PAN@BTO)quasi-solid-state electrolytes(PQSSEs)by electrostatic spinning method to suppress dendritic growth.The piezoelectric polymer electrolytes are squeezed by nucleation and growth processes of Li dendrites,which can generate a piezoelectric electric field to regulate the deposition of Li^(+)ions and eliminate lithium bud.Consequently,piezoelectric PAN@BTO PQSSEs enables highly stable Li plating/stripping cycling for over 2000 h at 0.15 mA/cm^(2)at room temperature(RT,25℃).Also,LiFePO_(4)|PAN@BTO|Li full cells demonstrate excellent cycle performance(136.9 mA·h/g and 78%retention after 600 cycles at 0.5 C)at RT.Moreover,LiFePO_(4)|PAN@BTO|Li battery show extremely high safety and can still work normally under high-speed impact(2 Hz,∼30 kPa).We construct an in-situ cell monitoring system and disclose that the mechanism of suppressed lithium dendrite is originated from the generation of opposite piezoelectric potential and the feedback speed of intermittent piezoelectric potential signals is extremely fast.展开更多
Background:The incidence of early-onset colorectal cancer(EOCRC)has increased globally since the early 1990s.Comprehensively examining the risk factors would be helpful for risk stratification and the development of p...Background:The incidence of early-onset colorectal cancer(EOCRC)has increased globally since the early 1990s.Comprehensively examining the risk factors would be helpful for risk stratification and the development of per-sonalized colorectal cancer screening strategies.Methods:We performed a prospective study of the Chinese population aged 30-50 years to identify potential risk factors during a median follow-up of 9.1 years.We compared the distribution of demographic characteris-tics,lifestyle factors,dietary habits,and medical history among 222 EOCRC cases and 87,833 normal controls.Multivariate adjusted Cox hazard models were used for estimating EOCRC risks of each risk factor.Results:Our final analyses indicated that participants with a higher body mass index(HR,1.04;95%CI:1.00,1.08),regular alcohol consumption(HR,1.69;95%CI:1.12,2.91),higher intake of fish(HR,1.64;95%CI:1.01,2.67),hypertension(HR,1.99;95%CI:1.04,3.81),diabetes(HR,2.20;95%CI:1.08,4.49),and first-degree relatives with cancer(HR,1.70;95%CI:1.23,2.36)were at higher risk of EOCRC.Conclusion:We identified several modifiable as well as nonmodifiable risk factors,such as higher BMI,alcohol and fish consumption,hypertension,and diabetes,were associated with EOCRC.展开更多
Background:Tumor heterogeneity is contributed by tumor cells and the microenvironment.Dynamics of tumor heterogeneity during colorectal cancer(CRC)progression have not been elucidated.Methods:Eight single-cell RNA seq...Background:Tumor heterogeneity is contributed by tumor cells and the microenvironment.Dynamics of tumor heterogeneity during colorectal cancer(CRC)progression have not been elucidated.Methods:Eight single-cell RNA sequencing(scRNA-seq)data sets of CRC were included.Milo was utilized to reveal the differential abundance of cell clusters during progression.The differentiation trajectory was imputed by using the Palantir algorithm and metabolic states were assessed by using scMetabolism.Three spatial transcription sequencing(ST-seq)data sets of CRC were used to validate cell-type abundances and colocalization.Cancer-associated regulatory hubs were defined as communication networks affecting tumor biological behaviors.Finally,quantitative reverse transcription polymerase chain reaction and immunohistochemistry staining were performed for validation.Results:TM4SF1t,SOX4t,and MKI67t tumor cells;CXCL12t cancer-associated fibroblasts;CD4t resident memory T cells;Treg;IgAt plasma cells;and several myeloid subsets were enriched in stage IV CRC,most of which were associated with overall survival of patients.Trajectory analysis indicated that tumor cells from patients with advanced-stage CRC were less differentiated,when metabolic heterogeneity showed a highest metabolic signature in terminal states of stromal cells,T cells,and myeloid cells.Moreover,ST-seq validated cell-type abundance in a spatial context and also revealed the correlation of immune infiltration between tertiary lymphoid structures and tumors followed by validation in our cohort.Importantly,analysis of cancer-associated regulatory hubs revealed a cascade of activated pathways including leukocyte apoptotic process,MAPK pathway,myeloid leukocyte differentiation,and angiogenesis during CRC progression.Conclusions:Tumor heterogeneity was dynamic during progression,with the enrichment of immunosuppressive Treg,myeloid cells,and fibrotic cells.The differential state of tumor cells was associated with cancer staging.Assessment of cancer-associated regulatory hubs suggested impaired antitumor immunity and increased metastatic ability during CRC progression.展开更多
基金supported by the Research Fund for International Scientists(RFIS-Grant numbers:52150410410)National Natural Science Foundation of Chinathe Deanship of Scientific Research and Graduate Studies at King Khalid University for funding this research work through Large Research Project under the grant number RGP2/121/1445.
文摘Inspired by molecular catalysts,researchers developed atomically precise nitrogen-coordinated single or dual metal sites imbedded in graphitized carbon(M-N-C)to fully utilize metallic sites for 02activation.These catalysts performed remarkably well in the electrocatalytic oxygen reduction reaction(ORR)due to their distinct coordination and electrical structures,Nonetheless,their maximum efficacy in practical applications has yet to be achieved.This agenda identifies tailoring the coordination environment,spin states,intersite distance,and metal-metal interaction as innovative approaches to regulate the ORR performance of these catalysts.However,it is necessary to undertake a precise assessment of these methodologies and the knowledge obtained to be implemented in the design of future M-N-C catalysts for ORR.Therefore,this review aims to analyze recent progress in M-N-C ORR catalysts,emphasizing their innovative engineering with aspects such as alteration in intersite distance,metal-metal interaction,coordination environment,and spin states.Additionally,we critically discuss how to logically monitor the atomic structure,local coordination,spin,and electronic states of M-N-C catalysts to modulate their ORR activity.We have also highlighted the challenges associated with M-N-C catalysts and proposed suggestions for their future design and fabrication.
基金Natural Science Foundation of China(Grant No.NSFC-22072062,22202098)。
文摘Designing highly active and stable electrocatalysts of oxygen evolution reaction(OER)is one of the crucial challenges.In this study,a novel OER electrocatalyst,NiFe-MIL-53 modified with ultra-low rhodium(Rh@NiFe-MIL-53),is successfully prepared via the hydrothermal method.In-situ Raman spectroscopy and electrochemical impedance spectroscopy reveal that the doped Rh accelerates the phase transformation of NiFe-MIL-53 and the in-situ formed Rh@NiFeOOH is the actual active species.More importantly,the enhanced reversibility of electrochemical reconstruction between NiFeOOH and NiFe(OH)_(2)after doping Rh is beneficial for improving the electrochemical stability of the catalyst.X-ray photoelectron spectroscopy spectra show the strong electronic interaction between single-atom Rh and Ni/Fe in Rh@NiFeOOH.Furthermore,theoretical calculations confirm that the integration of single-atom Rh into the NiFeOOH successfully reduces the band gap,regulates the d-band center(εd),accelerates the charge transfer,and optimizes the adsorption behavior of oxygen-containing intermediates,thereby lowering the energy barrier of rate-determining steps.Consequently,the optimized Rh@NiFe-MIL-53 exhibits excellent OER activity(240 mV)with a small Tafel slope of 48.2 mV dec^(-1)and long-term durability(over1270 h at 10 m A cm^(-2)and 110 h at 200 mA cm^(-2)).This work presents a new perspective on designing highly efficient OER electrocatalysts.
基金financial supported from the National Natural Science Foundation of China (Nos. 51977185 and 51972277)the financial supported from Southwest Jiaotong University Science and Technology Rising Star Program (No. 2682021CG021)
文摘Lithium-ion capacitors(LICs)are becoming important electrochemical energy storage systems due to their great potential to bridge the gap between supercapacitors and lithium-ion batteries.However,capacity lopsidedness and low output voltage greatly hinder the realization of high-energy-density LICs.Herein,a strategy of balancing capacity towards fastest dynamics is proposed to enable high-voltage LICs.Through electrochemical prelithiation of Nb_(2)C to be 1.1 V with 165 mAh g^(-1),Nb_(2)C//LiFePO_(4) LICs show a broadened potential window from 3.0 to 4.2 V and an according high energy density of 420 Wh kg^(-1).Moreover,the underlying mechanism between prelithiation and high voltage is disclosed by electrochemical dynamic analysis.Prelithiation declines the Nb_(2)C anode potential that facilitates electron transmission in the interlayer of two-dimensional Nb_(2)C MXene.This effect induces small drive force for Li^(+)ions deposition and hence weakens the repulsive force from adsorbed ions on the electrode surface.Benefiting from even more Li^(+)ions deposition,a higher voltage is eventually delivered.In addition,prelithiation significantly increases Coulomb efficiency of the 1st cycle from 74%to 90%,which is crucial to commercial application of LICs.
基金supported by the grants from the Natural Science Foundation of China (22072062)。
文摘Transition metal chalcogenides will be in situ transformed into metal oxyhydroxides during oxygen evolution reaction(OER) process in alkaline medium.However,most of these compounds only undergo surface reconstruction under operating conditions,which contains a large percentage of inactive atoms in the core,thus limiting the exposure of the active sites.Here,we synthesize a Ni-Mo-Se precatalyst with three-dimensional hierarchical structure and develop a facile on-site electrochemical activation strategy for achieving deep reconstruction of the precatalyst.Using the combination of multiple spectroscopic characterizations and high resolution electron microscopy techniques,we unravel that the Ni-Mo-Se precatalyst is deeply reconstructed into γ-NiOOH with co-leaching of Mo and Se after the anodic oxidation.Such flower-like γ-NiOOH is constituted by distorted ultrathin nanosheets with a thickness of ~4.5 nm and contains abundant intercalated species such as water and OH^(-)/CO_(3)^(2-) thus offering a large quantity of accessible active sites.To reach the current density of 10 mA cm^(-2),the derived electrode requires an overpotential of only 244 mV,outperforming almost all the reported analogues.This work highlights the reconstruction chemistry and provides a simple method for the preparation of efficient OER electrocatalyst.
基金supported by Natural Science Foundation of China (NSFC no. 21673105)the Science and Technology Program of Gansu Province of China (Grant No.1717JR5RA194)。
文摘Tuning surface electron transfer process by sulfur(S)-vacancies engineering is an efficient strategy to develop high-efficient catalysts for electroreduction N_(2) reaction(NRR). Herein, the distinct Sb_(2)S_(3) nanorods with S-vacancies(Sv-Sb_(2)S_(3)) have been synthesized by a simple twostep method including hydrothermal and hydrogenation in H_(2)/Ar atmosphere, which shows improved performance for NRR with the NH_(3) yield rate of 10.85 μg h^(-1) mgcat^(-1) at-0.4 V vs. RHE, the faradaic efficiency(FE) of 3.75% at -0.3 V vs. RHE and excellent stability for 24 h, largely outperforming bulk Sb_(2)S_(3). X-ray photoelectron spectroscopy(XPS) and density function theory(DFT) calculations demonstrate that the abundant S-vacancies can create an electron-deficient environment and modulate the electron delocalization in Sv-Sb_(2)S_(3), which can not only facilitate the N_(2) molecule adsorption, but also activate the N≡N, resulting in the enhanced performance for NRR.
基金supported by the STI2030-Major Projects(2021ZD0203900)Shanghai Municipal Science and Technology(22ZR1481500)+1 种基金"Strategic Priority Research Program"of the Chinese Academy of Sciences(XDB32010000)Shanghai Municipal Science and Technology Major Project(2018SHZDZX05).
文摘Dear Editor,The common marmoset(Callithrix jacchus),a small New World monkey species,is considered an ideal non-human primate model for studying the evolution and neural mechanism of vocal behavior due to their rich call repertoire and vocal communication[1-3].Especially,the early vocal development of marmoset monkeys has attracted much attention,because newborn marmosets have been shown to exhibit a vocal development trajectory.Within two months after birth,marmosets'vocalizations undergo dramatic changes from cries to adult-like mature calls,a process that is influenced not only by inner physical maturation but also by parental care and feedback[4].
基金the National Natural Science Foundation of China(Nos.51977185,51972277)the financial supported from Southwest Jiaotong University Science and Technology Rising Star Program(No.2682021CG021)
文摘lonic-conductive solid-state polymer electrolytes are promising for the development of advanced lithium batteries yet a deeper understanding of their underlying ion-transfer mechanism is needed to improve performance.Here we demonstrate the low-enthalpy and high-entropy(LEHE)electrolytes can intrinsically generate remarkably free ions and high mobility,enabling them to efficiently drive lithium-ion storage.The LEHE electrolytes are constructed on the basis of introducing CsPbl_(3)perovskite quantum dots(PQDs)to strengthen PEO@LiTFSI complexes.An extremely stable cycling>1000 h at 0.3 mA cm^(-2)can be delivered by LEHE electrolytes.Also,the as-developed Li|LEHE|LiFePO_(4)cell retains 92.3%of the initial capacity(160.7 mAh g^(-1))after 200 cycles.This cycling stability is ascribed to the suppressed charge concentration gradient leading to free lithium dendrites.It is realized by a dramatic increment in lithium-ion transference number(0.57 vs 0.19)and a significant decline in ion-transfer activation energy(0.14 eV vs 0.22 eV)for LEHE electrolytes comparing with PEO@LiTFSI counterpart.The CsPbl_(3)PQDs promote highly structural disorder by inhibiting crystallization and hence endow polymer electrolytes with low melting enthalpy and high structural entropy,which in turn facilitate long-term cycling stability and excellent rate-capability of lithium-metal batteries.
基金the National Natural Science Foundation of China (31371234)the project from the Ministry of Agriculture of China for transgenic research (2014ZX08009-27B)
文摘The secondary cell wall in mature cotton fibers contains over 90%cellulose with low quantities of xylan and lignin.However,little is known regarding the regulation of secondary cell wall biosynthesis in cotton fibers.In this study,we characterized an R2R3-MYB transcription factor,Gh MYB7,in cotton.Gh MYB7 is expressed at a high level in developing fibers and encodes a MYB protein that is targeted to the cell nucleus and has transcriptional activation activity.Ectopic expression of Gh MYB7 in Arabidopsis resulted in small,curled,dark green leaves and also led to shorter inflorescence stems.A cross-sectional assay of basal stems revealed that cell wall thickness of vessels and interfascicular fibers was higher in transgenic lines overexpressing Gh MYB7 than in the wild type.Constitutive expression of Gh MYB7 in Arabidopsis activated the expression of a suite of secondary cell wall biosynthesis-related genes(including some secondary cell wall-associated transcription factors),leading to the ectopic deposition of cellulose and lignin.The ectopic deposition of secondary cell walls may have been initiated before the cessation of cell expansion.Moreover,Gh MYB7 was capable of binding to the promoter regions of At SND1 and At Ces A4,suggesting that Gh MYB7 may function upstream of NAC transcription factors.Collectively,these findings suggest that Gh MYB7 is a potential transcriptional activator,which may participate in regulating secondary cell wall biosynthesis of cotton fibers.
基金supported by the National Natural Science Foundation of China (21673105)the support received from NSF under the award numbers OIA-1539035 and CHE-1539035supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Award No. DE-AC02-06CH11357
文摘The intrinsic activity and durability of oxygen evolution reaction(OER)electrocatalysts are mainly dominated by the surface and interface properties of active materials.Herein,a core-shell heterogeneous structure(NF/NiSe@Fe_(2)O_(3))is fabricated via two-step hydrothermal method,which exhibits a low overpotential of 220 mV(or 282 mV)at 10 mA/cm^(2)(or 200 mA/cm^(2)),a small Tafel slope of 36.9 mV/dec,and long-term stability(-230 h)in 1 mol/L KOH for OER.X-ray photoelectron spectroscopy and X-ray absorption spectroscopy reveal the(oxy)hydroxide-rich surface and strong coupling interface between NiSe and Fe_(2)O_(3)via the Fe-Se bond.Density functional theory calculation suggests that the d-band center and electronic state of NiSe@Fe_(2)O_(3)heterojunction are well optimized due to the formation of Fe-Se bond,which is favorable for the enhanced OER activity because of the easy adsorption of oxygen-containing intermediates and desorption of O^(2)in the OER process.In addition,the unique core-shell structure and robust bonding interface are responsible for the good stability for OER.This work provides fundamental insights on the bonding effect that determine the performance of OER electrocatalyst.
基金This work was financially supported by the National Natural Science Foundation of China(No.61801403)the Sichuan province Foundation for Distinguished Young Team(No.20CXTD0106)the Basic Research Cultivation Project(No.2682021ZTPY004).
文摘Monitoring physiological signals of the human body can provide extremely important information for sports healthcare,preventing injuries and providing efficient guidance for individual sports.However,the signals related to human healthcare involve both subtle and vigorous signals,making it difficult for a sensor to satisfy the full-scale monitoring at the same time.Here,a novel conductive elastomer featuring homogeneously micropyramid-structured PDMS/CNT composite is used to fabricate highperformance piezoresistive sensors by a drop-casting method.Benefiting from the significant increase in the contact area of microstructure during deformation,the flexible sensor presents a broad detection range(up to 185.5 kPa),fast response/recovery time(44/13 ms),ultrahigh sensitivity(242.4 kPa–1)and excellent durability over 8,000 cycles.As a proof of concept,the as-fabricated pressure sensor can be used for body-area sports healthcare,and enable the detection of full-scale pressure distribution.Considering the fabulous sensing performance,the sensor may potentially become promising in personal sports healthcare and telemedicine monitoring.
基金supported by the National Natural Science Foundation of China(Nos.22078261,21676213,and 11974276)the Natural Science Basic Research Program of Shaanxi(No.2020JM-422)。
文摘In this work,bimetallic NiCoP nanoparticles(NPs)were firstly prepared by a solvothermal method using red phosphorus(RP)as P source,and it was combined with RP nanosheets via a physical grinding process.Investigation indicates that NiCoP has better charge transfer ability and faster H_(2)releasing kinetics than the corresponding single metal phosphides alone.6 wt%NiCoP/RP exhibits an excellent H_(2)evolution activity in 20 vol.%triethanol-amine/water solution under a 300W Xe-lamp irradiation,and the corresponding H_(2)production rate is 1535.6μmol·g^(-1)·h^(-1),which is 7.4,3.2 and 2.6 times higher than those of pure RP,6 wt%Co_(2)P/RP and 6 wt%Ni_(2)P/RP,respectively.In addition,we demonstrate that K_(2)HPO_(4)can further enhance the H_(2)evolution kinetics by inducing a new H^(+)reduction path,when appropriate K_(2)HPO_(4)is introduced into the reaction solution.The H_(2)production rate of 6 wt%NiCoP/RP is boosted from 1535.6 to 2793.9μmol·g^(-1)·h^(-1) due to the easier combination between H^(+)and electrons with the assistance of HPO_(4)^(2-).It is 13.4 times higher than that of pure RP.This work demonstrates that bimetallic phosphides with suitable electrolytes can greatly enhance the photocatalytic H_(2)evolution efficiency.
基金supported by the National Natural Science Foundation of China(Nos.51977185,51972277)Natural Science Foundation of Sichuan Province(No.2023NSFSC0441).
文摘Polymer solid-state electrolytes(PSSEs)are promising for solving the safety problem of Lithium(Li)metal batteries(LMBs).However,PSSEs with low modulus in nature are prone to be penetrated by lithium dendrites,resulting in short circuit of LMBs.Here,we design and prepare piezoelectric BaTiO_(3)doped polyacrylonitrile(PAN@BTO)quasi-solid-state electrolytes(PQSSEs)by electrostatic spinning method to suppress dendritic growth.The piezoelectric polymer electrolytes are squeezed by nucleation and growth processes of Li dendrites,which can generate a piezoelectric electric field to regulate the deposition of Li^(+)ions and eliminate lithium bud.Consequently,piezoelectric PAN@BTO PQSSEs enables highly stable Li plating/stripping cycling for over 2000 h at 0.15 mA/cm^(2)at room temperature(RT,25℃).Also,LiFePO_(4)|PAN@BTO|Li full cells demonstrate excellent cycle performance(136.9 mA·h/g and 78%retention after 600 cycles at 0.5 C)at RT.Moreover,LiFePO_(4)|PAN@BTO|Li battery show extremely high safety and can still work normally under high-speed impact(2 Hz,∼30 kPa).We construct an in-situ cell monitoring system and disclose that the mechanism of suppressed lithium dendrite is originated from the generation of opposite piezoelectric potential and the feedback speed of intermittent piezoelectric potential signals is extremely fast.
基金the CKB study staffs for kindly help to our project(DAR-2020-00106)supported by Guangdong Basic and Applied Basic Research Foundation(grant number:2020A1515110056)Guangzhou Municipal Science&Technology Planning(grant number:202102010172).
文摘Background:The incidence of early-onset colorectal cancer(EOCRC)has increased globally since the early 1990s.Comprehensively examining the risk factors would be helpful for risk stratification and the development of per-sonalized colorectal cancer screening strategies.Methods:We performed a prospective study of the Chinese population aged 30-50 years to identify potential risk factors during a median follow-up of 9.1 years.We compared the distribution of demographic characteris-tics,lifestyle factors,dietary habits,and medical history among 222 EOCRC cases and 87,833 normal controls.Multivariate adjusted Cox hazard models were used for estimating EOCRC risks of each risk factor.Results:Our final analyses indicated that participants with a higher body mass index(HR,1.04;95%CI:1.00,1.08),regular alcohol consumption(HR,1.69;95%CI:1.12,2.91),higher intake of fish(HR,1.64;95%CI:1.01,2.67),hypertension(HR,1.99;95%CI:1.04,3.81),diabetes(HR,2.20;95%CI:1.08,4.49),and first-degree relatives with cancer(HR,1.70;95%CI:1.23,2.36)were at higher risk of EOCRC.Conclusion:We identified several modifiable as well as nonmodifiable risk factors,such as higher BMI,alcohol and fish consumption,hypertension,and diabetes,were associated with EOCRC.
基金supported by the National Key Research and Development Program of China[grant number 2022YFA1304000]the National Natural Science Foundation of China Key Joint Project[grant number U21A20344]+5 种基金the National Natural Science Foundation of China[grant number 81970452]the Program of Guangdong Provincial Clinical Research Center for Digestive Diseases[grant number 2020B1111170004]the Science and Technology Program of Shenzhen,China[grant number JCYJ20190807161807867]the Starting Funding of Faculty from Sun Yat-sen University[grant number 2021276]the Regional Joint Project for Basic and Applied Basic Research Fund of Guangdong Province[grant number 2022A1515111043]the Science and Technology Planning Project of Guangzhou City[grant number 2023A04J01601],and National Key Clinical Discipline.
文摘Background:Tumor heterogeneity is contributed by tumor cells and the microenvironment.Dynamics of tumor heterogeneity during colorectal cancer(CRC)progression have not been elucidated.Methods:Eight single-cell RNA sequencing(scRNA-seq)data sets of CRC were included.Milo was utilized to reveal the differential abundance of cell clusters during progression.The differentiation trajectory was imputed by using the Palantir algorithm and metabolic states were assessed by using scMetabolism.Three spatial transcription sequencing(ST-seq)data sets of CRC were used to validate cell-type abundances and colocalization.Cancer-associated regulatory hubs were defined as communication networks affecting tumor biological behaviors.Finally,quantitative reverse transcription polymerase chain reaction and immunohistochemistry staining were performed for validation.Results:TM4SF1t,SOX4t,and MKI67t tumor cells;CXCL12t cancer-associated fibroblasts;CD4t resident memory T cells;Treg;IgAt plasma cells;and several myeloid subsets were enriched in stage IV CRC,most of which were associated with overall survival of patients.Trajectory analysis indicated that tumor cells from patients with advanced-stage CRC were less differentiated,when metabolic heterogeneity showed a highest metabolic signature in terminal states of stromal cells,T cells,and myeloid cells.Moreover,ST-seq validated cell-type abundance in a spatial context and also revealed the correlation of immune infiltration between tertiary lymphoid structures and tumors followed by validation in our cohort.Importantly,analysis of cancer-associated regulatory hubs revealed a cascade of activated pathways including leukocyte apoptotic process,MAPK pathway,myeloid leukocyte differentiation,and angiogenesis during CRC progression.Conclusions:Tumor heterogeneity was dynamic during progression,with the enrichment of immunosuppressive Treg,myeloid cells,and fibrotic cells.The differential state of tumor cells was associated with cancer staging.Assessment of cancer-associated regulatory hubs suggested impaired antitumor immunity and increased metastatic ability during CRC progression.
