Objectives:Human epidermal growth factor receptor 2(HER2)-targeted therapies have demonstrated potential benefits for metastatic colorectal cancer(mCRC)patients with HER2 amplification,but are not satisfactory in case...Objectives:Human epidermal growth factor receptor 2(HER2)-targeted therapies have demonstrated potential benefits for metastatic colorectal cancer(mCRC)patients with HER2 amplification,but are not satisfactory in cases of HER2 mutant CRCs.Methods:Consequently,further elucidation of amplifications and somatic mutations in erythroblastic oncogene B-2(ERBB2)is imperative.Comprehensive genomic profiling was conducted on 2454 Chinese CRC cases to evaluate genomic alterations in 733 cancer-related genes,tumor mutational burden,microsatellite instability,and programmed death ligand 1(PD-L1)expression.Results:Among 2454 CRC patients,85 cases(3.46%)exhibited ERBB2 amplification,and 55 cases(2.24%)carried ERBB2 mutation.p.R678Q(28%),p.V8421(24%),and p.S310F/Y(12%)were the most prevalent of the 16 detected mutation sites.In comparison to the ERBB2 altered(alt)group,KRAS/BRAF mutations were more prevalent in ERBB2 wild-type(wt)samples(ERBB2wt vs.ERBB2alt,KRAS:50.9%vs.25.6%,p<0.05;BRAF:8.5%vs.2.3%,p<0.05).32.7%(18/55)of CRCs with ERBB2 mutation exhibited microsatellite instability high(MSI-H),while no cases with HER2 amplification displayed MSI-H.Mutant genes varied between ERBB2 copy number variation(CNV)and ERBB2 single nucleotide variant(SNV);TP53 alterations tended to co-occur with ERBB2 amplification(92.3%)as opposed to ERBB2 mutation(58.3%).KRAS and PIK3CA alterations were more prevalent in ERBB2 SNV cases(KRAS/PIK3CA:45.8%/31.2%)compared to ERBB2 amplification cases(KRAS/PIK3CA:14.1%/7.7%).Conclusion:Our study delineates the landscape of HER2 alterations in a large-scale cohort of CRC patients from China.These findings enhance our understanding of the molecular features of Chinese CRC patients and offer valuable implications for further investigation.展开更多
The development of renewable woods for power generation can help improve the energy efficiency of buildings,and promote the concept design and implementation of“smart buildings”.Here,with specific chemical treatment...The development of renewable woods for power generation can help improve the energy efficiency of buildings,and promote the concept design and implementation of“smart buildings”.Here,with specific chemical treatment and hydrothermal synthesis,we demonstrated the practical value of natural wood for thermoelectric power generation in smart buildings.The prepared wood-based thermoelectric sponges show high Seebeck coefficients of 320.5 and 436.6μV/K in the vertical and parallel directions of the longitudinal channel of wood.After 500 cycles of the compressive strain at 20%,the corresponding Seebeck coefficients increase up to 413.4 and 502.1μV/K,respectively,which is attributed to the improved contact and connection between tellurium thermoelectric nanowires.The Seebeck coefficients are much larger than those of most reported inorganic thermoelectric materials.Meanwhile,the thermoelectric sponges maintain excellent thermoelectric and mechanical stability.We further modeled the application value of wood-based thermoelectric sponges in smart buildings for power generation.Relatively high thermoelectric electricity can be obtained,such as in Beijing with over 1.5 million kWh every year,demonstrating the great potential in thermal energy harvest and energy supply.展开更多
The demand for lightweight,thin electromagnetic interference(EMI)shielding film materials with high shielding effectiveness(SE),excellent mechanical properties,and stability in complex environments is particularly pro...The demand for lightweight,thin electromagnetic interference(EMI)shielding film materials with high shielding effectiveness(SE),excellent mechanical properties,and stability in complex environments is particularly pronounced in the realm of flexible and portable electronic products.Here,we developed an ultra-thin film(CNT@GC)in which the glassy carbon(GC)layer wrapped around and welded carbon nanotubes(CNTs)to form a core-shell network structure,leading to exceptional tensile strength(327.2 MPa)and electrical conductivity(2.87×10^(5) S·m^(−1)).The CNT@GC film achieved EMI SE of 60 dB at a thickness of 2µm after post-acid treatment and high specific SE of 3.49×10^(5) dB·cm^(2)·g^(−1),with comprehensive properties surpassing those of the majority of previous shielding materials.Additionally,the CNT@GC film exhibited Joule heating capability,reaching a surface temperature of 135℃at 3 V with a fast thermal response of about 0.5 s,enabling anti-icing/de-icing functionality.This work presented a methodology for constructing a robust CNT@GC film with high EMI shielding performance and exceptional Joule heating capability,demonstrating immense potential in wearable devices,defense,and aerospace applications.展开更多
An intrinsic magnetic topological insulator(TI) is a stoichiometric magnetic compound possessing both inherent magnetic order and topological electronic states. Such a material can provide a shortcut to various novel ...An intrinsic magnetic topological insulator(TI) is a stoichiometric magnetic compound possessing both inherent magnetic order and topological electronic states. Such a material can provide a shortcut to various novel topological quantum effects but remained elusive experimentally for a long time. Here we report the experimental realization of thin films of an intrinsic magnetic TI, MnBi2Te4, by alternate growth of a Bi2Te3 quintuple layer and a MnTe bilayer with molecular beam epitaxy. The material shows the archetypical Dirac surface states in angle-resolved photoemission spectroscopy and is demonstrated to be an antiferromagnetic topological insulator with ferromagnetic surfaces by magnetic and transport measurements as well as first-principles calculations. The unique magnetic and topological electronic structures and their interplays enable the material to embody rich quantum phases such as quantum anomalous Hall insulators and axion insulators at higher temperature and in a well-controlled way.展开更多
Lithium-sulfur(Li-S)batteries are regarded as one of the promising candidates for the next-generation energy storage system owing to their high capacity and energy density.However,the durable operation for the batteri...Lithium-sulfur(Li-S)batteries are regarded as one of the promising candidates for the next-generation energy storage system owing to their high capacity and energy density.However,the durable operation for the batteries is blocked by the shuttle behavior of soluble lithium polysulfides and the sluggish kinetics in the redox process.Here,VN nanoparticles on nitrogen-doped graphene(VN/NG)composite is synthesized by simple calcining method to modify the separators,which can not only chemically trap polysulfides,but also catalyze the conversion reaction between the polysulfides and the insoluble Li2S during the charge/discharge process.The catalytic effects of VN/NG are verified by the calculated activation energy(E_(a)),which is smaller than the counterpart with NG toward both directions of redox.Because of the synergistic adsorption-catalysis of VN/NG,the cells with VN/NG-modified separators deliver a superior rate performance(791 mAh g^(-1) at 5C)and cycling stability(863 mAh g^(-1) after 300 cycles with a low decaying rate of 0.068%per loop at 1C).This work provides a simple preparation strategy and fundamental understanding of the bifunctional catalyst for high-performance Li-S batteries.展开更多
The increasing penetration of renewable energy on the transmission and distribution power network is driving the adoption of two-way power flow control, data and communications needed to meet the dependency of balanci...The increasing penetration of renewable energy on the transmission and distribution power network is driving the adoption of two-way power flow control, data and communications needed to meet the dependency of balancing generation and load. Thus, creating an environment where power and information flow seamlessly in real time to enable reliable and economically viable energy delivery, the advent of Internet of Energy(IoE) as well as the rising of Internet of Things(IoT) based smart systems.The evolution of IT to Io T has shown that an information network can be connected in an autonomous way via routers from operating system(OS) based computers and devices to build a highly intelligent eco-system. Conceptually, we are applying the same methodology to the Io E concept so that Energy Operating System(EOS) based assets and devices can be developed into a distributed energy network via energy gateway and self-organized into a smart energy eco-system.This paper introduces a laboratory based IIo T driven software and controls platform developed on the NICE Nano-grid as part of a NICE smart system Initiative for Shenhua group. The goal of this effort is to develop an open architecture based Industrial Smart Energy Consortium(ISEC) to attract industrial partners, academic universities, module supplies, equipment vendors and related stakeholder to explore and contribute into a test-bed centric open laboratory template and platform for next generation energy-oriented smart industry applications.In the meanwhile, ISEC will play an important role to drive interoperability standards for the mining industry so that the era of un-manned underground mining operation can become the reality as well as increasing safety regulation enforcement.展开更多
A calculation method of heat transfer area for vertical natural circulated steam generator was introduced. According to the design requirements of steam generator 55/19 of CPR1000, its heat transfer area was calculate...A calculation method of heat transfer area for vertical natural circulated steam generator was introduced. According to the design requirements of steam generator 55/19 of CPR1000, its heat transfer area was calculated based on this method. The results show that the accuracy of partitional and overall calculation method is almost the same, but the result is different when using different calculation models. And the results are compared with the foreign companies for 55/19 steam generator.展开更多
The effect of partial substitution of Mg for Ni on a high-sodium and lithium-free layered P2-type Na_(45/54)Mg_(6)/_(54)Ni_(12/54)Mn_(34/54)O_(2) cathode with high initial Coulombic efficiency and excellent cyclic sta...The effect of partial substitution of Mg for Ni on a high-sodium and lithium-free layered P2-type Na_(45/54)Mg_(6)/_(54)Ni_(12/54)Mn_(34/54)O_(2) cathode with high initial Coulombic efficiency and excellent cyclic stability has been investigated in this study.Based on the crystal structural analysis,the Mg doping can retain the P2 structure up to 4.3 V,thus restraining the detrimental phase transformation of P2-02during the Na-ion intercalation/deintercalation process.Therefore,the obtained Mg-doped P2-type cathode exhibits a reversible specific capacity of 109 mAh·g^(-1) at 0.1C between 2.0 and 4.3 V and a retention rate of 81.5% after 200cycles at 1C.In addition,the full cell consisting of Mg-doped P2-type cathode and hard carbon anode shows a capacity retention rate of 85.6% after 100 cycles.This study provides new insight into the development of durable cathode materials for sodium-ion batteries.展开更多
Developing highly robust and efficient electrode materials is of critical importance to promoting the energy density of current supercapacitors for commercialization.Herein,we report an efficient catalyst with monodis...Developing highly robust and efficient electrode materials is of critical importance to promoting the energy density of current supercapacitors for commercialization.Herein,we report an efficient catalyst with monodispersed Mn single-atoms embedded in carbon nanotubes(Mn-CNTs)for enhancing the electrode performance of supercapacitors.A high specific capacitance(1523.6 F·g^(-1) at 1.0 A·g^(-1))can be achieved,which is about twice as high as the specific capacitance of the electrode material without the introduction of Mn single-atoms.Remarkably,the asymmetric electrochemical capacitor created with Mn-CNT and activated carbon exhibits a high energy density of 180.8 Wh·kg^(-1) at a power density of 1.4 kW·kg^(-1),much higher than most reported results.The study shows that the integration of Mn atoms into the CNT can enhance the charge transport capacity and the number of polar active sites of Mn-CNT and then facilitate chemical interactions between Mn-CNT and OH-.This work provides a novel strategy to enable high-energy storage in supercapacitors by introducing single-atoms into carbon nanotubes to improve electrodes’energy density and cycle life.展开更多
Yttrium iron garnet(YIG)is a promising material for various terahertz applications due to its special optical properties.At present,a high-quality YIG wafer is the desire of terahertz communities and it is still chall...Yttrium iron garnet(YIG)is a promising material for various terahertz applications due to its special optical properties.At present,a high-quality YIG wafer is the desire of terahertz communities and it is still challenging to prepare substrate-free YIG single crystal films.In this work,we prepared wafer-level substrate-free La:YIG single crystal films,for the first time,to our knowledge.Terahertz optical and magneto-optical properties of La:YIG films were characterized by terahertz time domain spectroscopy(THz-TDS).Results show that the as-prepared La:YIG film has an insertion loss of less than 3 dB and a low absorption coefficient of less than10 cm-1below 1.6 THz.Benefitting from the thickness of the substrate-free YIG films and low insertion loss,their terahertz properties could be further manipulated by simply using a wafer-stacking technique.When four La:YIG films were stacked,there was an insertion loss of less than 10 dB in the range of 0.1-1.2 THz.The Faraday rotation angle of the four-layer-stacked La:YIG films reached 19°,and the isolation could reach17 dB.By further increasing the stacking number to eight pieces,a remarkable Faraday rotation angle of45°was achieved with an isolation of 23 dB,which is important for practical application in the THz band.This material may provide a milestone opportunity to make various non-reciprocal devices,such as isolators and phase shifters.展开更多
As one of the most rapidly expanding materials,hydrogels have gained increasing attention in a variety of fields due to their biocompatibility,degradability and hydrophilic properties,as well as their remarkable adhes...As one of the most rapidly expanding materials,hydrogels have gained increasing attention in a variety of fields due to their biocompatibility,degradability and hydrophilic properties,as well as their remarkable adhesion and stretchability to adapt to different surfaces.Hydrogels combined with carbon-based materials possess enhanced properties and new functionalities,in particular,conductive hydrogels have become a new area of research in the field of materials science.This review aims to provide a comprehensive overview and up-to-date examination of recent developments in the synthesis,properties and applications of conductive hydrogels incorporating several typical carbon nanoparticles such as carbon nanotubes,graphene,carbon dots and carbon nanofibers.We summarize key techniques and mechanisms for synthesizing various composite hydrogels with exceptional properties,and represented applications such as wearable sensors,temperature sensors,supercapacitors and human-computer interaction reported recently.The mechanical,electrical and sensing properties of carbon nanoparticles conductive hydrogels are thoroughly analyzed to disclose the role of carbon nanoparticles in these hydrogels and key factors in the microstructure.Finally,future development of conductive hydrogels based on carbon nanoparticles is discussed including the challenges and possible solutions in terms of microstructure optimization,mechanical and other properties,and promising applications in wearable electronics and multifunctional materials.展开更多
Surface electromyography(sEMG)is widely used in monitoring human health.Nonetheless,it is challenging to capture high-fidelity sEMG recordings in regions with intricate curved surfaces such as the larynx,because regul...Surface electromyography(sEMG)is widely used in monitoring human health.Nonetheless,it is challenging to capture high-fidelity sEMG recordings in regions with intricate curved surfaces such as the larynx,because regular sEMG electrodes have stiff structures.In this study,we developed a stretchable,high-density sEMG electrode array via layerby-layer printing and lamination.The electrode offered a series of excellent human‒machine interface features,including conformal adhesion to the skin,high electron-to-ion conductivity(and thus lower contact impedance),prolonged environmental adaptability to resist water evaporation,and epidermal biocompatibility.This made the electrode more appropriate than commercial electrodes for long-term wearable,high-fidelity sEMG recording devices at complicated skin interfaces.Systematic in vivo studies were used to investigate its ability to classify swallowing activities,which was accomplished with high accuracy by decoding the sEMG signals from the chin via integration with an ear-mounted wearable system and machine learning algorithms.The results demonstrated the clinical feasibility of the system for noninvasive and comfortable recognition of swallowing motions for comfortable dysphagia rehabilitation.展开更多
Thermo-electrochemical cells(TECs)provide a new potential for self-powered devices by converting heat energy into electricity.However,challenges still remain in the fabrication of flexible and tough gel electrolytes a...Thermo-electrochemical cells(TECs)provide a new potential for self-powered devices by converting heat energy into electricity.However,challenges still remain in the fabrication of flexible and tough gel electrolytes and their compat-ibility with redox actives;otherwise,contact problems exist between electrolytes and electrodes during stretching or twisting.Here,a novel robust and neutral hydrogel with outstanding stretchability was developed via double-network of crosslinked carboxymethyl chitosan and polyacrylamide,which accommodated both n-type(Fe^(2+)/Fe^(3+))and p-type([Fe(CN)_(6)]^(3-)/[Fe(CN)_(6)]^(4-))redox couples and maintained stretchability(>300%)and recoverability(95%compression).Moreover,poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)textile elec-trodes with porous structure are integrated into gel electrolytes that avoid contact issues and effectively boost the P_(max) of n-and p-type thermocell by 76%and 26%,respectively.The optimized thermocell exhibits a quick current density response and is continually fully operational under deformations,which satisfies the working conditions of wearable devices.Multiple thermocells(four pairs)are effectively connected in alternating single n-and p-type cells in series and out-putted nearly 74.3 mV atΔT=10℃.The wearable device is manufactured into a soft-pack thermocells to successfully harvest human body heat and illuminate an LED,demonstrating the potential of the actual application of the thermocell devices.展开更多
In this paper, nonconforming quasi-Wilson finite element approximation to a class of nonlinear sine-Gordan equations is discussed. Based on the known higher accuracy results of bilinear element and different technique...In this paper, nonconforming quasi-Wilson finite element approximation to a class of nonlinear sine-Gordan equations is discussed. Based on the known higher accuracy results of bilinear element and different techniques from the existing literature, it is proved that the inner product △↓(u - Ih^1u), △↓vh) and the consistency error can be estimated as order O(h^2) in broken H^1 - norm/L^2 - norm when u ∈ H^3(Ω)/H^4(Ω), where Ih^1u is the bilinear interpolation of u, Vh belongs to the quasi-Wilson finite element space. At the same time, the superclose result with order O(h^2) for semi-discrete scheme under generalized rectangular meshes is derived. Furthermore, a fully-discrete scheme is proposed and the corresponding error estimate of order O(h^2 + τ^2) is obtained for the rectangular partition when u ∈ H^4(Ω), which is as same as that of the bilinear element with ADI scheme and one order higher than that of the usual analysis on nonconforming finite elements.展开更多
In this paper, we develop a unique time-varying forecasting model for dynamic demand of medical resources based on a susceptible-exposed-infected-recovered (SEIR) influenza diffusion model. In this forecasting mecha...In this paper, we develop a unique time-varying forecasting model for dynamic demand of medical resources based on a susceptible-exposed-infected-recovered (SEIR) influenza diffusion model. In this forecasting mechanism, medical resources allocated in the early period will take effect in subduing the spread of influenza and thus impact the demand in the later period. We adopt a discrete time-space network to describe the medical resources allocation process following a hypothetical influenza outbreak in a region. The entire medical resources allocation process is constructed as a multi-stage integer programming problem. At each stage, we solve a cost minimization sub-problem subject to the time-varying demand. The corresponding optimal allocation result is then used as an input to the control process of influenza spread, which in turn determines the demand for the next stage. In addition, we present a comparison between the proposed model and an empirical model. Our results could help decision makers prepare for a pandemic, including how to allocate limited resources dynamically.展开更多
The pairing mechanism of high-temperature superconductivity in cuprates remains the biggest unresolved mystery in condensed matter physics. To solve the problem, one of the most effective approaches is to investigate ...The pairing mechanism of high-temperature superconductivity in cuprates remains the biggest unresolved mystery in condensed matter physics. To solve the problem, one of the most effective approaches is to investigate directly the superconducting CuO2 layers. Here, by growing CuO2 monolayer films on Bi2Sr2CaCu2O8+δ substrates, we identify two distinct and spatially separated energy gaps centered at the Fermi energy, a smaller U-like gap and a larger V-like gap on the films, and study their interactions with alien atoms by low-temperature scanning tunneling microscopy. The newly discovered U-like gap exhibits strong phase coherence and is immune to scattering by K, Cs and Ag atoms, suggesting its nature as a nodeless superconducting gap in the CuO2 layers, whereas the V-like gap agrees with the well-known pseudogap state in the underdoped regime. Our results support an s-wave superconductivity in Bi2Sr2CaCu2O8+δ, which, we pro- pose, originates from the modulation-doping resultant twodimensional hole liquid confined in the CuO2 layers.展开更多
Stretchable strain sensors play an increasingly important role in artificial intelligent devices.However,high-performanee strain sensors havebeen slowly developed owing to the harsh requirement of self-powered functio...Stretchable strain sensors play an increasingly important role in artificial intelligent devices.However,high-performanee strain sensors havebeen slowly developed owing to the harsh requirement of self-powered function,long cycle life and high resolution.Here,we report aself-powered stretchable graphene-ecoflex composite strain sensor based on photo-thermoelectric(PTE)effect induced electricity.Thedevice exhibits a high strain sensitivity of-0.056 In(nA)/%with strains ranged from 0%to 20%under 980 nm light illumination,where thestrain sensitivity can be found to in crease with in creasi ng light inte nsity.The strain sensor maintains outstanding dyn amic stability un derperiodic strains ranged from 0 to 100%in 100 cycles.The sensing resolution can be as high as 0.5%with both the response and recovery timeof less than 0.6 s.It can precisely monitor human joint motions and stretchable strains by implanting the device in pork.展开更多
基金sponsored by National Natural Science Foundation of China(Grant Numbers 81972280,81972290)Natural Science Foundation of Shanghai(Grant Number 23ZR1452300)+2 种基金Research Grant for Health Science and Technology of Pudong Health Bureau of Shanghai(Grant Number PW2022E-02)Academic Leaders Training Program of Pudong Health Bureau of Shanghai(Grant Number PWRd2022-02)Foundation of Beijing CSCO Clinical Oncology Research(Grant Number Y-HR2019-0384).
文摘Objectives:Human epidermal growth factor receptor 2(HER2)-targeted therapies have demonstrated potential benefits for metastatic colorectal cancer(mCRC)patients with HER2 amplification,but are not satisfactory in cases of HER2 mutant CRCs.Methods:Consequently,further elucidation of amplifications and somatic mutations in erythroblastic oncogene B-2(ERBB2)is imperative.Comprehensive genomic profiling was conducted on 2454 Chinese CRC cases to evaluate genomic alterations in 733 cancer-related genes,tumor mutational burden,microsatellite instability,and programmed death ligand 1(PD-L1)expression.Results:Among 2454 CRC patients,85 cases(3.46%)exhibited ERBB2 amplification,and 55 cases(2.24%)carried ERBB2 mutation.p.R678Q(28%),p.V8421(24%),and p.S310F/Y(12%)were the most prevalent of the 16 detected mutation sites.In comparison to the ERBB2 altered(alt)group,KRAS/BRAF mutations were more prevalent in ERBB2 wild-type(wt)samples(ERBB2wt vs.ERBB2alt,KRAS:50.9%vs.25.6%,p<0.05;BRAF:8.5%vs.2.3%,p<0.05).32.7%(18/55)of CRCs with ERBB2 mutation exhibited microsatellite instability high(MSI-H),while no cases with HER2 amplification displayed MSI-H.Mutant genes varied between ERBB2 copy number variation(CNV)and ERBB2 single nucleotide variant(SNV);TP53 alterations tended to co-occur with ERBB2 amplification(92.3%)as opposed to ERBB2 mutation(58.3%).KRAS and PIK3CA alterations were more prevalent in ERBB2 SNV cases(KRAS/PIK3CA:45.8%/31.2%)compared to ERBB2 amplification cases(KRAS/PIK3CA:14.1%/7.7%).Conclusion:Our study delineates the landscape of HER2 alterations in a large-scale cohort of CRC patients from China.These findings enhance our understanding of the molecular features of Chinese CRC patients and offer valuable implications for further investigation.
基金the National Key R&D Program of China(No.2020YFA0711500)the National Natural Science Fund of China(Nos.51973095,52273248,and 52303238)the Key Project of Natural Science Foundation of Tianjin City(No.21JCZDJC00010).
文摘The development of renewable woods for power generation can help improve the energy efficiency of buildings,and promote the concept design and implementation of“smart buildings”.Here,with specific chemical treatment and hydrothermal synthesis,we demonstrated the practical value of natural wood for thermoelectric power generation in smart buildings.The prepared wood-based thermoelectric sponges show high Seebeck coefficients of 320.5 and 436.6μV/K in the vertical and parallel directions of the longitudinal channel of wood.After 500 cycles of the compressive strain at 20%,the corresponding Seebeck coefficients increase up to 413.4 and 502.1μV/K,respectively,which is attributed to the improved contact and connection between tellurium thermoelectric nanowires.The Seebeck coefficients are much larger than those of most reported inorganic thermoelectric materials.Meanwhile,the thermoelectric sponges maintain excellent thermoelectric and mechanical stability.We further modeled the application value of wood-based thermoelectric sponges in smart buildings for power generation.Relatively high thermoelectric electricity can be obtained,such as in Beijing with over 1.5 million kWh every year,demonstrating the great potential in thermal energy harvest and energy supply.
基金supported by the National Key Research and Development Program of China(No.2020YFA0210702)the National Natural Science Foundation of China(No.51872267)+1 种基金the Natural Science Foundation of Henan Province,China(No.202300410371)Program for Science&Technology Innovation Talents in Universities of Henan Province(No.21HASTIT017).
文摘The demand for lightweight,thin electromagnetic interference(EMI)shielding film materials with high shielding effectiveness(SE),excellent mechanical properties,and stability in complex environments is particularly pronounced in the realm of flexible and portable electronic products.Here,we developed an ultra-thin film(CNT@GC)in which the glassy carbon(GC)layer wrapped around and welded carbon nanotubes(CNTs)to form a core-shell network structure,leading to exceptional tensile strength(327.2 MPa)and electrical conductivity(2.87×10^(5) S·m^(−1)).The CNT@GC film achieved EMI SE of 60 dB at a thickness of 2µm after post-acid treatment and high specific SE of 3.49×10^(5) dB·cm^(2)·g^(−1),with comprehensive properties surpassing those of the majority of previous shielding materials.Additionally,the CNT@GC film exhibited Joule heating capability,reaching a surface temperature of 135℃at 3 V with a fast thermal response of about 0.5 s,enabling anti-icing/de-icing functionality.This work presented a methodology for constructing a robust CNT@GC film with high EMI shielding performance and exceptional Joule heating capability,demonstrating immense potential in wearable devices,defense,and aerospace applications.
基金Supported by the Ministry of Science and Technology of Chinathe National Science Foundation of Chinathe Beijing Advanced Innovation Center for Future Chip(ICFC)
文摘An intrinsic magnetic topological insulator(TI) is a stoichiometric magnetic compound possessing both inherent magnetic order and topological electronic states. Such a material can provide a shortcut to various novel topological quantum effects but remained elusive experimentally for a long time. Here we report the experimental realization of thin films of an intrinsic magnetic TI, MnBi2Te4, by alternate growth of a Bi2Te3 quintuple layer and a MnTe bilayer with molecular beam epitaxy. The material shows the archetypical Dirac surface states in angle-resolved photoemission spectroscopy and is demonstrated to be an antiferromagnetic topological insulator with ferromagnetic surfaces by magnetic and transport measurements as well as first-principles calculations. The unique magnetic and topological electronic structures and their interplays enable the material to embody rich quantum phases such as quantum anomalous Hall insulators and axion insulators at higher temperature and in a well-controlled way.
基金supported by the National Natural Science Foun-dation of China(21706171,21606158,21978193 and U1810204)the Natural Science Foundation of Shanxi Province(201805D131004 and 201901D211064)。
文摘Lithium-sulfur(Li-S)batteries are regarded as one of the promising candidates for the next-generation energy storage system owing to their high capacity and energy density.However,the durable operation for the batteries is blocked by the shuttle behavior of soluble lithium polysulfides and the sluggish kinetics in the redox process.Here,VN nanoparticles on nitrogen-doped graphene(VN/NG)composite is synthesized by simple calcining method to modify the separators,which can not only chemically trap polysulfides,but also catalyze the conversion reaction between the polysulfides and the insoluble Li2S during the charge/discharge process.The catalytic effects of VN/NG are verified by the calculated activation energy(E_(a)),which is smaller than the counterpart with NG toward both directions of redox.Because of the synergistic adsorption-catalysis of VN/NG,the cells with VN/NG-modified separators deliver a superior rate performance(791 mAh g^(-1) at 5C)and cycling stability(863 mAh g^(-1) after 300 cycles with a low decaying rate of 0.068%per loop at 1C).This work provides a simple preparation strategy and fundamental understanding of the bifunctional catalyst for high-performance Li-S batteries.
基金supported by National Key Research and Development Program(2016YFE0102600)National Natural Science Foundation of China(51577096,51477082)
文摘The increasing penetration of renewable energy on the transmission and distribution power network is driving the adoption of two-way power flow control, data and communications needed to meet the dependency of balancing generation and load. Thus, creating an environment where power and information flow seamlessly in real time to enable reliable and economically viable energy delivery, the advent of Internet of Energy(IoE) as well as the rising of Internet of Things(IoT) based smart systems.The evolution of IT to Io T has shown that an information network can be connected in an autonomous way via routers from operating system(OS) based computers and devices to build a highly intelligent eco-system. Conceptually, we are applying the same methodology to the Io E concept so that Energy Operating System(EOS) based assets and devices can be developed into a distributed energy network via energy gateway and self-organized into a smart energy eco-system.This paper introduces a laboratory based IIo T driven software and controls platform developed on the NICE Nano-grid as part of a NICE smart system Initiative for Shenhua group. The goal of this effort is to develop an open architecture based Industrial Smart Energy Consortium(ISEC) to attract industrial partners, academic universities, module supplies, equipment vendors and related stakeholder to explore and contribute into a test-bed centric open laboratory template and platform for next generation energy-oriented smart industry applications.In the meanwhile, ISEC will play an important role to drive interoperability standards for the mining industry so that the era of un-manned underground mining operation can become the reality as well as increasing safety regulation enforcement.
文摘A calculation method of heat transfer area for vertical natural circulated steam generator was introduced. According to the design requirements of steam generator 55/19 of CPR1000, its heat transfer area was calculated based on this method. The results show that the accuracy of partitional and overall calculation method is almost the same, but the result is different when using different calculation models. And the results are compared with the foreign companies for 55/19 steam generator.
基金financially supported by the National Natural Science Foundation of China (No.21978193)the Natural Science Foundation of Shanxi Province (Nos.20210302123107, 20181102005, and 20181102019)。
文摘The effect of partial substitution of Mg for Ni on a high-sodium and lithium-free layered P2-type Na_(45/54)Mg_(6)/_(54)Ni_(12/54)Mn_(34/54)O_(2) cathode with high initial Coulombic efficiency and excellent cyclic stability has been investigated in this study.Based on the crystal structural analysis,the Mg doping can retain the P2 structure up to 4.3 V,thus restraining the detrimental phase transformation of P2-02during the Na-ion intercalation/deintercalation process.Therefore,the obtained Mg-doped P2-type cathode exhibits a reversible specific capacity of 109 mAh·g^(-1) at 0.1C between 2.0 and 4.3 V and a retention rate of 81.5% after 200cycles at 1C.In addition,the full cell consisting of Mg-doped P2-type cathode and hard carbon anode shows a capacity retention rate of 85.6% after 100 cycles.This study provides new insight into the development of durable cathode materials for sodium-ion batteries.
基金supported by the Yunnan provincial education department scientific research fund project(No.2022J0815)Special Youth Project for Fundamental Research in Yunnan Province(No.202301AU070227)+3 种基金the National Natural Science Foundation of China(No.12264056)Yunnan Expert Workstation(No.202205AF150008)support from the International Joint Research Center for Intelligent Nano Environmental Protection New Materials and Testing Technology(No.SDGH2108)the Collaborative Innovation Center of Suzhou Nano Science&Technology,the 111 Project,and Joint International Research Laboratory of Carbon-Based Functional Materials and Devices.
文摘Developing highly robust and efficient electrode materials is of critical importance to promoting the energy density of current supercapacitors for commercialization.Herein,we report an efficient catalyst with monodispersed Mn single-atoms embedded in carbon nanotubes(Mn-CNTs)for enhancing the electrode performance of supercapacitors.A high specific capacitance(1523.6 F·g^(-1) at 1.0 A·g^(-1))can be achieved,which is about twice as high as the specific capacitance of the electrode material without the introduction of Mn single-atoms.Remarkably,the asymmetric electrochemical capacitor created with Mn-CNT and activated carbon exhibits a high energy density of 180.8 Wh·kg^(-1) at a power density of 1.4 kW·kg^(-1),much higher than most reported results.The study shows that the integration of Mn atoms into the CNT can enhance the charge transport capacity and the number of polar active sites of Mn-CNT and then facilitate chemical interactions between Mn-CNT and OH-.This work provides a novel strategy to enable high-energy storage in supercapacitors by introducing single-atoms into carbon nanotubes to improve electrodes’energy density and cycle life.
基金National Key Research and Development Program of China(2023YFB3811300,2023YFB3811305)National Natural Science Foundation of China(62235004,61831012,62371258,62311530115)+1 种基金Sichuan Province Science and Technology Support Program(2021JDTD0026,2023JDGD0012)Shenzhen Science and Technology Program((2021)105)。
文摘Yttrium iron garnet(YIG)is a promising material for various terahertz applications due to its special optical properties.At present,a high-quality YIG wafer is the desire of terahertz communities and it is still challenging to prepare substrate-free YIG single crystal films.In this work,we prepared wafer-level substrate-free La:YIG single crystal films,for the first time,to our knowledge.Terahertz optical and magneto-optical properties of La:YIG films were characterized by terahertz time domain spectroscopy(THz-TDS).Results show that the as-prepared La:YIG film has an insertion loss of less than 3 dB and a low absorption coefficient of less than10 cm-1below 1.6 THz.Benefitting from the thickness of the substrate-free YIG films and low insertion loss,their terahertz properties could be further manipulated by simply using a wafer-stacking technique.When four La:YIG films were stacked,there was an insertion loss of less than 10 dB in the range of 0.1-1.2 THz.The Faraday rotation angle of the four-layer-stacked La:YIG films reached 19°,and the isolation could reach17 dB.By further increasing the stacking number to eight pieces,a remarkable Faraday rotation angle of45°was achieved with an isolation of 23 dB,which is important for practical application in the THz band.This material may provide a milestone opportunity to make various non-reciprocal devices,such as isolators and phase shifters.
基金Guangxi University of Traditional Chinese Medicine Postgraduate Education Innovation Project (Grant No. YCBXJ2022009)Guilin Science and Technology Bureau (Grant No. 2020011208-5)National Natural Science Foundation of China (Grant No. 81973768)。
文摘随着干细胞在阿尔茨海默病的研究越来越多,这项研究已经成为该领域的研究热点。干细胞疗法是最具前景的一种治疗方法。本研究通过文献计量学可视化分析,以探索干细胞在阿尔茨海默病的研究热点和趋势。构建干细胞对阿尔茨海默病研究的检索式,数据来自Web of Science Core Collection database,使用Cite Space和VOS viewer软件对2002至2021年的文献数据进行分析。干细胞对AD的研究涉及94个国家/地区,共有3629个机构参与,每年呈上升趋势,其中美国和中国是主要的研究国家。Takahashi团队首次培养出诱导多能干细胞,成为众多研究者理论的来源。University of California System是研究成果影响最大的机构, Plos One是最受欢迎的期刊, Maiese发现SIRT1是AD的治疗靶点,并且他的研究成果最多。研究重点包括Brain,Dentate gyrus,Amyloid-beta,Oxidative stress,Neurodegeneration,Inflammation,Pluripotent stem cells, Neural stem cells, Microglia。我们的研究揭示了干细胞在AD中的全球研究趋势,目前研究的热点是诱导多能干细胞模型在AD中的研究,为该领域的研究工作者提高了重要的信息和参考。
基金This work was supported by the National Key R&D Program of China(grant No.2020YFA0210702)National Natural Science Foundation of China(grant No.51872267)+2 种基金the Natural Science Foundation of Henan Province,China(grant No.202300410371)Program for Science&Technology Innovation Talents in Universities of Henan Province(grant No.21HASTIT017)Foundation of Henan Province Educational Committee(grant No.23A140005).
文摘As one of the most rapidly expanding materials,hydrogels have gained increasing attention in a variety of fields due to their biocompatibility,degradability and hydrophilic properties,as well as their remarkable adhesion and stretchability to adapt to different surfaces.Hydrogels combined with carbon-based materials possess enhanced properties and new functionalities,in particular,conductive hydrogels have become a new area of research in the field of materials science.This review aims to provide a comprehensive overview and up-to-date examination of recent developments in the synthesis,properties and applications of conductive hydrogels incorporating several typical carbon nanoparticles such as carbon nanotubes,graphene,carbon dots and carbon nanofibers.We summarize key techniques and mechanisms for synthesizing various composite hydrogels with exceptional properties,and represented applications such as wearable sensors,temperature sensors,supercapacitors and human-computer interaction reported recently.The mechanical,electrical and sensing properties of carbon nanoparticles conductive hydrogels are thoroughly analyzed to disclose the role of carbon nanoparticles in these hydrogels and key factors in the microstructure.Finally,future development of conductive hydrogels based on carbon nanoparticles is discussed including the challenges and possible solutions in terms of microstructure optimization,mechanical and other properties,and promising applications in wearable electronics and multifunctional materials.
基金supported by the National Natural Science Foundation of China(grant numbers 42177440 and 51903079)National Natural Science Foundation of China(grant no.52075177)+1 种基金National Key Research and Development Program of China(grant no.2021YFB3301400)Research Foundation of Guangdong Province(grant no.2019A050505001).
文摘Surface electromyography(sEMG)is widely used in monitoring human health.Nonetheless,it is challenging to capture high-fidelity sEMG recordings in regions with intricate curved surfaces such as the larynx,because regular sEMG electrodes have stiff structures.In this study,we developed a stretchable,high-density sEMG electrode array via layerby-layer printing and lamination.The electrode offered a series of excellent human‒machine interface features,including conformal adhesion to the skin,high electron-to-ion conductivity(and thus lower contact impedance),prolonged environmental adaptability to resist water evaporation,and epidermal biocompatibility.This made the electrode more appropriate than commercial electrodes for long-term wearable,high-fidelity sEMG recording devices at complicated skin interfaces.Systematic in vivo studies were used to investigate its ability to classify swallowing activities,which was accomplished with high accuracy by decoding the sEMG signals from the chin via integration with an ear-mounted wearable system and machine learning algorithms.The results demonstrated the clinical feasibility of the system for noninvasive and comfortable recognition of swallowing motions for comfortable dysphagia rehabilitation.
基金National Key R&D Program of China,Grant/Award Number:2020YFA0711500National Natural Science Foundation of China,Grant/Award Numbers:52273248,52303238,52002050+2 种基金Key Project of Natural Science Foundation of Tianjin City,Grant/Award Number:21JCZDJC00010Science&Technology Department of Sichuan Province,China,Grant/Award Number:2023NSFSC0993Australian Research Council,Grant/Award Numbers:DP170102320,CE140100012。
文摘Thermo-electrochemical cells(TECs)provide a new potential for self-powered devices by converting heat energy into electricity.However,challenges still remain in the fabrication of flexible and tough gel electrolytes and their compat-ibility with redox actives;otherwise,contact problems exist between electrolytes and electrodes during stretching or twisting.Here,a novel robust and neutral hydrogel with outstanding stretchability was developed via double-network of crosslinked carboxymethyl chitosan and polyacrylamide,which accommodated both n-type(Fe^(2+)/Fe^(3+))and p-type([Fe(CN)_(6)]^(3-)/[Fe(CN)_(6)]^(4-))redox couples and maintained stretchability(>300%)and recoverability(95%compression).Moreover,poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)textile elec-trodes with porous structure are integrated into gel electrolytes that avoid contact issues and effectively boost the P_(max) of n-and p-type thermocell by 76%and 26%,respectively.The optimized thermocell exhibits a quick current density response and is continually fully operational under deformations,which satisfies the working conditions of wearable devices.Multiple thermocells(four pairs)are effectively connected in alternating single n-and p-type cells in series and out-putted nearly 74.3 mV atΔT=10℃.The wearable device is manufactured into a soft-pack thermocells to successfully harvest human body heat and illuminate an LED,demonstrating the potential of the actual application of the thermocell devices.
文摘In this paper, nonconforming quasi-Wilson finite element approximation to a class of nonlinear sine-Gordan equations is discussed. Based on the known higher accuracy results of bilinear element and different techniques from the existing literature, it is proved that the inner product △↓(u - Ih^1u), △↓vh) and the consistency error can be estimated as order O(h^2) in broken H^1 - norm/L^2 - norm when u ∈ H^3(Ω)/H^4(Ω), where Ih^1u is the bilinear interpolation of u, Vh belongs to the quasi-Wilson finite element space. At the same time, the superclose result with order O(h^2) for semi-discrete scheme under generalized rectangular meshes is derived. Furthermore, a fully-discrete scheme is proposed and the corresponding error estimate of order O(h^2 + τ^2) is obtained for the rectangular partition when u ∈ H^4(Ω), which is as same as that of the bilinear element with ADI scheme and one order higher than that of the usual analysis on nonconforming finite elements.
基金partially supported by the National Natural Science Foundation of China (No.71301076,71401075)Natural Science Foundation of Jiangsu Province(BK20130771)+1 种基金the Research Fund for the Doctoral Program of Higher Education of China(20133219120037)the Zijin Intelligent Program(No. 2013-ZJ0211) of Nanjing University of Science and Technology
文摘In this paper, we develop a unique time-varying forecasting model for dynamic demand of medical resources based on a susceptible-exposed-infected-recovered (SEIR) influenza diffusion model. In this forecasting mechanism, medical resources allocated in the early period will take effect in subduing the spread of influenza and thus impact the demand in the later period. We adopt a discrete time-space network to describe the medical resources allocation process following a hypothetical influenza outbreak in a region. The entire medical resources allocation process is constructed as a multi-stage integer programming problem. At each stage, we solve a cost minimization sub-problem subject to the time-varying demand. The corresponding optimal allocation result is then used as an input to the control process of influenza spread, which in turn determines the demand for the next stage. In addition, we present a comparison between the proposed model and an empirical model. Our results could help decision makers prepare for a pandemic, including how to allocate limited resources dynamically.
基金Acknowledgments The work was financially supported by the National Natural Science Foundation, Ministry of Science and Technology and Ministry of Education of China. The work at Brookhaven National Laboratory was supported by the Office of Basic Energy Sciences, US Department of Energy, under Contract No. DE- SC00112704.
文摘The pairing mechanism of high-temperature superconductivity in cuprates remains the biggest unresolved mystery in condensed matter physics. To solve the problem, one of the most effective approaches is to investigate directly the superconducting CuO2 layers. Here, by growing CuO2 monolayer films on Bi2Sr2CaCu2O8+δ substrates, we identify two distinct and spatially separated energy gaps centered at the Fermi energy, a smaller U-like gap and a larger V-like gap on the films, and study their interactions with alien atoms by low-temperature scanning tunneling microscopy. The newly discovered U-like gap exhibits strong phase coherence and is immune to scattering by K, Cs and Ag atoms, suggesting its nature as a nodeless superconducting gap in the CuO2 layers, whereas the V-like gap agrees with the well-known pseudogap state in the underdoped regime. Our results support an s-wave superconductivity in Bi2Sr2CaCu2O8+δ, which, we pro- pose, originates from the modulation-doping resultant twodimensional hole liquid confined in the CuO2 layers.
基金This work was supported by the National Key R&D Program of China(No.2016YFA0202701)the National Natural Science Foundation of China(No.51472055)+4 种基金External Cooperation Program of BIC,Chinese Academy of Sciences(No.121411KYS820150028)the 2015 Annual Beijing Talents Fund(No.2015000021223ZK32)Qingdao National Laboratory for Marine Science and Technology(No.2017ASKJ01)the University of Chinese Academy of Sciences(No.Y8540XX2D2)the"thousands talents"program for the pioneer researcher and his innovation team,China.
文摘Stretchable strain sensors play an increasingly important role in artificial intelligent devices.However,high-performanee strain sensors havebeen slowly developed owing to the harsh requirement of self-powered function,long cycle life and high resolution.Here,we report aself-powered stretchable graphene-ecoflex composite strain sensor based on photo-thermoelectric(PTE)effect induced electricity.Thedevice exhibits a high strain sensitivity of-0.056 In(nA)/%with strains ranged from 0%to 20%under 980 nm light illumination,where thestrain sensitivity can be found to in crease with in creasi ng light inte nsity.The strain sensor maintains outstanding dyn amic stability un derperiodic strains ranged from 0 to 100%in 100 cycles.The sensing resolution can be as high as 0.5%with both the response and recovery timeof less than 0.6 s.It can precisely monitor human joint motions and stretchable strains by implanting the device in pork.