It remains challenging to effectively estimate the remaining capacity of the secondary lithium-ion batteries that have been widely adopted for consumer electronics,energy storage,and electric vehicles.Herein,by integr...It remains challenging to effectively estimate the remaining capacity of the secondary lithium-ion batteries that have been widely adopted for consumer electronics,energy storage,and electric vehicles.Herein,by integrating regular real-time current short pulse tests with data-driven Gaussian process regression algorithm,an efficient battery estimation has been successfully developed and validated for batteries with capacity ranging from 100%of the state of health(SOH)to below 50%,reaching an average accuracy as high as 95%.Interestingly,the proposed pulse test strategy for battery capacity measurement could reduce test time by more than 80%compared with regular long charge/discharge tests.The short-term features of the current pulse test were selected for an optimal training process.Data at different voltage stages and state of charge(SOC)are collected and explored to find the most suitable estimation model.In particular,we explore the validity of five different machine-learning methods for estimating capacity driven by pulse features,whereas Gaussian process regression with Matern kernel performs the best,providing guidance for future exploration.The new strategy of combining short pulse tests with machine-learning algorithms could further open window for efficiently forecasting lithium-ion battery remaining capacity.展开更多
The conversion of CO_(2)into value-added chemicals coupled with the storage of intermittent renewable electricity is attractive.CuO nanosheets with an average size and thickness of~30 and~20 nm have been developed,whi...The conversion of CO_(2)into value-added chemicals coupled with the storage of intermittent renewable electricity is attractive.CuO nanosheets with an average size and thickness of~30 and~20 nm have been developed,which are in situ reduced into Cu nanosheets during electrochemical CO_(2)reduction reaction(ECO_(2)RR).The derived Cu nanosheets demonstrate much higher selectivity for C2H4production than commercial CuO derived Cu powder,with an optimum Faradaic efficiency of 56.2%and a partial current density of C_(2)H_(4)as large as 171.0 mA cm^(-2)in a gas diffusion flow cell.The operando attenuated total reflectance-Fourier transform infrared spectra measurements and density functional theory simulations illustrate that the high activity and selectivity of Cu nanosheets originate from the edge sites on Cu nanosheets with a coordinate number around 5(4–6),which facilitates the formation of^(*)CHO rather than^(*)COH intermediate,meanwhile boosting the C-C coupling reaction of^(*)CO and^(*)CHO intermediates,which are the critical steps for C_(2)H_(4)formation.展开更多
Objective To screen antigen targets for immunotherapy by analyzing over-expressed genes,and to identify significant pathways and molecular mechanisms in esophageal cancer by using bioinformatic methods such as enrichm...Objective To screen antigen targets for immunotherapy by analyzing over-expressed genes,and to identify significant pathways and molecular mechanisms in esophageal cancer by using bioinformatic methods such as enrichment analysis,protein-protein interaction(PPI)network,and survival analysis based on the Gene Expression Omnibus(GEO)database.Methods By screening with highly expressed genes,we mainly analyzed proteins MUC13 and EPCAM with transmembrane domain and antigen epitope from TMHMM and IEDB websites.Significant genes and pathways associated with the pathogenesis of esophageal cancer were identified using enrichment analysis,PPI network,and survival analysis.Several software and platforms including Prism 8,R language,Cytoscape,DAVID,STRING,and GEPIA platform were used in the search and/or figure creation.Results Genes MUC13 and EPCAM were over-expressed with several antigen epitopes in esophageal squamous cell carcinoma(ESCC)tissue.Enrichment analysis revealed that the process of keratinization was focused and a series of genes were related with the development of esophageal cancer.Four genes including ALDH3A1,C2,SLC6A1,and ZBTB7C were screened with significant P value of survival curve.Conclusions Genes MUC13 and EPCAM may be promising antigen targets or biomarkers for esophageal cancer.Keratinization may greatly impact the pathogenesis of esophageal cancer.Genes ALDH3A1,C2,SLC6A1,and ZBTB7C may play important roles in the development of esophageal cancer.展开更多
Introduction:Sulfatase 2(SULF2),an endogenous extracellular sulfatase,can remove 6-O-sulfate groups of glucosamine residues from heparan sulfate(HS)chains to modulate the Wnt/β-catenin signaling pathway,which plays a...Introduction:Sulfatase 2(SULF2),an endogenous extracellular sulfatase,can remove 6-O-sulfate groups of glucosamine residues from heparan sulfate(HS)chains to modulate the Wnt/β-catenin signaling pathway,which plays an important role in both liver carcinogenesis and embryogenesis.Side population(SP)cells are widely identified as stem-like cancer cells and are closely related to carcinoma metastasis,recurrence,and poor patient prognosis.However,the roles of SULF2 in SP cells of hepatomas are unclear,and the underlying mechanism is undefined.Objectives:This study aimed to compare the heterogeneity between SP cells and non-side population(NSP)cells derived from three different liver cancer cell lines and to elucidate the involvement of the SULF2-Wnt/β-catenin axis in liver cancer stem cells(CSCs)and its impact on the processes of carcinogenesis and invasiveness.Methods:In this work,three different liver cancer SP cells(HepG2,Huh7,and PRC/PRL/5)were sorted by flow cytometry.We also examined the migration and invasion behaviors of SP and NSP cells.To determine if this high tumorigenic potential of SP cells is correlated to SULF2,qPCR,western blotting,and immunofluorescence analysis were conducted.We also performed nude mouse xenograft experiments for in vivo analysis.Results:The results from the in vitro colony formation assay showed that SP cells exhibited a 2-fold higher colony formation efficiency compared to their NSP counterparts.The SP cells exhibited significantly higher potentials in terms of their migratory capacity and invasive ability compared to NSP cells.We found that higher expression of SULF2 in SP cells was associated with greater capabilities for clonogenicity,migration,and invasion.It was also linked to higher activation of the Wnt/β-catenin signaling pathway via stimulation of key downstream factors,particularlyβ-catenin,c-Myc,and cyclin D1.Further,a positive correlation between the upregulated SULF2 expression and tumorigenesis in the in vivo nude mouse xenograft models was demonstrated,highlighting that the potential underlying mechanism was Wnt/β-catenin signaling pathway activation.Conclusion:Our findings show that variable SULF2 expression was associated with differential activation of the Wnt/β-catenin signaling pathway,which could lead to behavioral differences between SP and NSP cells and also among the SP cells of the three liver cancer cell lines assessed.It was reasonably concluded that the SULF2-Wnt/β-catenin axis could play an important role in the tumorigenicity of liver cancer stem cells.展开更多
Fourier light-field microscopy(FLFM)uses a microlens aray(MLA)to segment the Fourierplane of the microscopic objective lens to generate multiple two-dimensional perspective views,thereby reconstructing the threedimens...Fourier light-field microscopy(FLFM)uses a microlens aray(MLA)to segment the Fourierplane of the microscopic objective lens to generate multiple two-dimensional perspective views,thereby reconstructing the threedimensional(3D)structure of the sample using 3D deconvo-lution calculation without scanning.However,the resolution of FLFM is stil limited by dif-fraction,and furthermore,it is dependent on the aperture division.In order to improve itsresolution,a super-resolution opticai fuctuation Fourier light-field microscopy(SOFFLFM)wasproposed here,in which the super-resolution optical fluctuation imaging(SOFI)with the abilityof super-resolution was introduced into FLFM.SOFFLFM uses higher-order cumulants statis-tical analysis on an image sequence collected by FLFM,and then carries out 3D deconvolutioncalculation to reconstruct the 3D structure of the sample.The theoretical basis of SOFFLFM onimproving resolution was explained and then verified with the simulations.Simulation resultsdemonstrated that SOFFLFM improved the lateral and axial resolution by more than V2 and 2times in the second-and fourth-order accumulations,compared with that of FLFM.展开更多
Carbon materials are considered to be one of the most promising anode materials for sodium-ion batteries(SIBs),but the well-ordered graphitic structure limits the intercalation of sodium ions.Besides,the sluggish inte...Carbon materials are considered to be one of the most promising anode materials for sodium-ion batteries(SIBs),but the well-ordered graphitic structure limits the intercalation of sodium ions.Besides,the sluggish intercalation kinetics of sodium ions impedes the rate performance.Thus,the precise structure control of carbon materials is important to improve the battery performance.Herein,a 3D porous hard-soft composite carbon(3DHSC)was prepared using the NaCl as the template and phenolic resin and pitch as carbon precursors.The NaCl template restrains the growth of the graphite crystallite during the carbonization process,resulting in small graphitic domains with expanded interlayer spacing which is favorable for the sodium storage.Moreover,the Na Cl templates help to create abundant mesopores and macropores for fast sodium ion diffusion.The porous structure and the graphite crystalline structure can be precisely controlled by simply adjusting the mass ratio of Na Cl,and thus,the suitable structure can be prepared to reach high capacity and rate performance while keeping a relatively high Coulombic efficiency.Typically,a high reversible capacity(215 mA h g^(-1)at 0.05 A g^(-1)),an excellent rate capability(97 mA h g^(-1)at 5 A g^(-1)),and a high initial Coulombic efficiency(60%)are achieved.展开更多
Objective:Organoids have recently been used as in vitro models to screen chemotherapy drugs in combination with hyperthermia treatment in colorectal cancer.Our research aimed to establish a library of patient-derived ...Objective:Organoids have recently been used as in vitro models to screen chemotherapy drugs in combination with hyperthermia treatment in colorectal cancer.Our research aimed to establish a library of patient-derived colorectal cancer organoids to evaluate synergism between chemotherapy drugs and hyperthermia;validate an index of the hyperthermia chemotherapy sensitization enhancement ratio(HCSER)to identify the chemotherapeutics most enhanced by hyperthermia;and recommend chemotherapy drugs for hyperthermic intraperitoneal treatment.Methods:Organoids were grown from cells extracted from colorectal cancer patient samples or colorectal cancer cell lines.Cells from both sources were encapsulated in 3 D Matrigel droplets,which were formulated in microfluidics and phase-transferred into identical cell-laden Matrigel microspheres.The microspheres were seeded in 96-well plates,with each well containing a single microsphere that developed into an organoid after 7 days.The organoids were used to evaluate the efficacy of chemotherapy drugs at both 37℃ as a control and 43℃ for 90 min to examine hyperthermia synergism.Cell viability was counted with 10%CCK8.Results:We successfully established a library of colorectal cancer organoids from 22 patient parental tumors.We examined the hyperthermia synergism of 7 commonly used hyperthermic intraperitoneal chemotherapy drugs.In 11 of the 22 patient organoids,raltitrexed had significant hyperthermia synergism,which was indexed as the highest HCSER score within each patient group.Conclusions:Our results primarily demonstrated the use of patient-derived colorectal cancer organoids as in vitro models to evaluate hyperthermia synergistic chemotherapeutics.We found that hyperthermia enhanced the effect of raltitrexed the most among the common anti-colorectal cancer drugs.展开更多
The marvelously diverse Orchidaceae constitutes the largest family of angiosperms.The genus Cymbidium in Orchidaceae is well known for its unique vegetation,floral morphology,and flower scent traits.Here,a chromosomes...The marvelously diverse Orchidaceae constitutes the largest family of angiosperms.The genus Cymbidium in Orchidaceae is well known for its unique vegetation,floral morphology,and flower scent traits.Here,a chromosomescale assembly of the genome of Cymbidium ensifolium(Jianlan)is presented.Comparative genomic analysis showed that C.ensifolium has experienced two whole-genome duplication(WGD)events,the most recent of which was shared by all orchids,while the older event was the t event shared by most monocots.The results of MADS-box genes analysis provided support for establishing a unique gene model of orchid flower development regulation,and flower shape mutations in C.ensifolium were shown to be associated with the abnormal expression of MADS-box genes.The most abundant floral scent components identi fied included methyl jasmonate,acacia alcohol and linalool,and the genes involved in the floral scent component network of C.ensifolium were determined.Furthermore,the decreased expression of photosynthesis-antennae and photosynthesis metabolic pathway genes in leaves was shown to result in colorful striped leaves,while the increased expression of MADS-box genes in leaves led to perianth-like leaves.Our results provide fundamental insights into orchid evolution and diversi fication.展开更多
Due to their outstanding anti-flashover characteristics,composite insulators have been extensively applied in power systems.A lot of research has investigated flashover characteristics of hydrophobic specimens with ar...Due to their outstanding anti-flashover characteristics,composite insulators have been extensively applied in power systems.A lot of research has investigated flashover characteristics of hydrophobic specimens with artificial water droplets.However,the phenomenon is not consistent with that of the contaminated composite insulators.On the test specimens covered with water droplets,there is no obvious leakage current before the flashover and no obvious relationship between flashover voltage and the conductivity of water droplets.On the contaminated composite insulator surface,there are short continuous arcs on the insulators before critical flashover,making insulators look like a luminous lantern.Considering that under these two conditions,the proportion of water along the insulation distance is different,the flashover characteristic of“dry band-water band”on a hydrophobicity surface is analyzed in the present study.The influence of the water band parameter(including length,width,and conductivity)as well as the length of dry band is studied.On this basis,the arc generation and development process of the surface covered with“dry band-water band”is analyzed.The research results improve the understanding of the flashover process on contaminated composite insulators.展开更多
Composite insulators are generally considered to have excellent anti-pollution flashover performance,but recently there has been a flashover accident on the indoor clean insulator in China,which is suspected to be rel...Composite insulators are generally considered to have excellent anti-pollution flashover performance,but recently there has been a flashover accident on the indoor clean insulator in China,which is suspected to be related to the wetting of insulators through condensation.Therefore,this paper studied the water condensation on hydrophobic surfaces.The changes in the mass,length,and proportion of the water droplets on the hydrophobic surface during the wetting process were measured,and the influence of wetting degree on the flashover characteristics was studied.It was found that the insulator surface temperature lower than the dew point is a prerequisite for the wetting of the clean hydrophobic surface,and the wetting velocity increases with the electric field.The results could provide some reference for understanding the insulator flashover accidents.展开更多
Heterogeneous photocatalysis has gained substantial research interest in treating per-and polyfluoroalkyl substances(PFAS)-contaminated water.However,sluggish degradation kinetics and low defluorination efficiency com...Heterogeneous photocatalysis has gained substantial research interest in treating per-and polyfluoroalkyl substances(PFAS)-contaminated water.However,sluggish degradation kinetics and low defluorination efficiency compromise their practical applications.Here,we report a superior photocatalyst,defected Bi_(3)O(OH)(PO_(4))_(2),which could effectively degrade typical PFAS,perfluorooctanoic acid(PFOA),with high defluorination efficiency.The UV light irradiation could in situ generate oxygen vacancies on Bi_(3)O(OH)(PO_(4))_(2) through oxidation of the lattice hydroxyls,which further promotes the formation of Lewis acidic coordinately unsaturated bismuth sites.Then,the Lewis acidic sites couple with the proximal surface hydroxyls to constitute the surface frustrated Lewis pairs(SFLPs).With the in-depth spectroscopic analysis,we revealed that the photo-induced SFLPs act as collection centers to effectively adsorb PFOA and endow accessible pathways to transfer photogenerated holes to PFOA rapidly.Consequently,activation of the terminal carboxyl,a ratelimiting step for PFOA decomposition,could be easily achieved over the defected Bi_(3)O(OH)(PO_(4))_(2) photocatalyst.These results suggest that SFLPs exhibit great potential in developing highly efficient photocatalysts to degrade persistent organic pollutants.展开更多
Microplastics(MPs)have been one of the most concerned environmental issues since the 21st century.MPs are plastic particles with diameters less than 5 mm,which are widely sourced in the aquatic environment.After being...Microplastics(MPs)have been one of the most concerned environmental issues since the 21st century.MPs are plastic particles with diameters less than 5 mm,which are widely sourced in the aquatic environment.After being released into the aquatic environment,MPs would experience complicated physical,chemical and biological aging processes driven by mechanical forces,photooxidation,and biological degradation,which would result in changes in MPs’physicochemical properties,such as the particle size,specific surface area,hydrophobicity,crystallinity,etc.In this review,we have illustrated the current study status on MPs’environmental aging processes and pointed out the knowledge gaps.MPs’aging processes would consequentially influence MPs’interaction with the co-existing organic and inorganic pollutants in the aquatic environment as well as lead to the leaching of chemical additives involved in plastic production,including plasticizers and flame retardants,which can trigger high ecotoxicity to the aquatic environment.Furthermore,aged MPs would cause ecotoxicity to aquatic organisms via bioaccumulation,biomagnification,and indirect carrier pathways.The review would provide an in-depth overview of MPs’environmental aging processes and consequential ecotoxicity implications,as well as propose future research needs.展开更多
Due to their excellent advantages such as low toxicity,superior optoelectronic properties,low-temperature fabrication,and costeffectiveness,Sn-based perovskites have become the most promising alternatives for high per...Due to their excellent advantages such as low toxicity,superior optoelectronic properties,low-temperature fabrication,and costeffectiveness,Sn-based perovskites have become the most promising alternatives for high performance lead-free perovskite solar cells.However,the character of Sn ^(2+)is easily oxidized toSn ^(4+),causing unnecessary p-type self-doping and high leakage current.More seriously,trap-induced non-radiative recombination from rapid crystallization causes into large energy loss with a low open circuit voltage.Therefore,the Sn-based solar cells have efficiency far behind the Pb-based solar cells.Herein,the polymer poly(ethylene glycol)diacrylate(PEGDA)is used to control crystal growth and passivate the defects in FA_(0.85)PEA_(0.15)SnI_(3) thin film.This Sn-perovskite layer shows compact crystal with large grain size and reduced defects.Optimized perovskite thin film is further processed to fabricate the inverted solar cell with device structure of ITO(indium tin oxide)/PEDOT:PSS(Poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate))/FA_(0.85)PEA_(0.15)SnI_(3)/ICBA(indene-C60 bisadduct)/BCP(bathocuproine)/Ag,which shows the power conversion efficiency(PCE)of 11.45%with voltage of 0.82 V.Moreover,corresponding perovskite solar cells exhibit an enhanced stability due to PEGDA induced compressive strain in perovskite.This work could shed light on one of successful attempts to improve Sn-based solar cell efficiency for sustainable energy conversion.展开更多
Virtual simulation testing of Autonomous Vehicles(AVs)is gradually being accepted as a mandatory way to test the feasibility of driving strategies for AVs.Mainstream methods focus on improving testing efficiency by ex...Virtual simulation testing of Autonomous Vehicles(AVs)is gradually being accepted as a mandatory way to test the feasibility of driving strategies for AVs.Mainstream methods focus on improving testing efficiency by extracting critical scenarios from naturalistic driving datasets.However,the criticalities defined in their testing tasks are based on fixed assumptions,the obtained scenarios cannot pose a challenge to AVs with different strategies.To fill this gap,we propose an intelligent testing method based on operable testing tasks.We found that the driving behavior of Surrounding Vehicles(SVs)has a critical impact on AV,which can be used to adjust the testing task difficulty to find more challenging scenarios.To model different driving behaviors,we utilize behavioral utility functions with binary driving strategies.Further,we construct a vehicle interaction model,based on which we theoretically analyze the impact of changing the driving behaviors on the testing task difficulty.Finally,by adjusting SV’s strategies,we can generate more corner cases when testing different AVs in a finite number of simulations.展开更多
Graphene, with unique two-dimensional form and numerous appealing properties, promises to remarkably increase the energy density and power density of electrochemical energy storage devices(EESDs),ranging from the popu...Graphene, with unique two-dimensional form and numerous appealing properties, promises to remarkably increase the energy density and power density of electrochemical energy storage devices(EESDs),ranging from the popular lithium ion batteries and supercapacitors to next-generation high-energy batteries. Here, we review the recent advances of the state-of-the-art graphene-based materials for EESDs,including lithium ion batteries, supercapacitors, micro-supercapacitors, high-energy lithium-air and lithium-sulfur batteries, and discuss the importance of the pore, doping, assembly, hybridization and functionalization of different nano-architectures in improving electrochemical performance. The major roles of graphene are highlighted as(1) a superior active material,(2) ultrathin 2D flexible support,and(3) an inactive yet electrically conductive additive. Furthermore, we address the enormous potential of graphene for constructing new-concept emerging graphene-enabled EESDs with multiple functionalities of lightweight, ultra-flexibility, thinness, and novel cell configurations. Finally, future perspectives and challenges of graphene-based EESDs are briefly discussed.展开更多
Tailoring the pore structure and surface chemistry of graphene-based laminates is essentially important for their applications as separation membranes.Usually,pure graphene oxide(GO) and completely reduced GO(r GO) me...Tailoring the pore structure and surface chemistry of graphene-based laminates is essentially important for their applications as separation membranes.Usually,pure graphene oxide(GO) and completely reduced GO(r GO) membranes suffer from low water permeance because of the lack of pristine graphitic sp^2 domains and very small interlayer spacing,respectively.In this work,we studied the influence of reduction degree on the structure and separation performance of r GO membranes.It was found that weak reduction retains the good dispersion and hydrophilicity of GO nanosheets.More importantly,it increases the number of pristine graphitic sp^2 domains in rGO nanosheets while keeping the large interlayer spacing of the GO membranes in most regions at the same time.The resultant membranes show a high water permeance of 56.3 L m^(-2)h^(-1)bar^(-1),which is about 4 times and over 10~4 times larger than those of the GO and completely reduced r GO membranes,respectively,and high rejection over 95% for various dyes.Furthermore,they show better structure stability and more superior separation performance than GO membranes in acid and alkali environments.展开更多
The reviving use of lithium metal anode(LMA)is one of the most promising ways to upgrade the energy density of lithium ion batteries.In the roadmap towards the real use,besides the formation of the dendrite,various ad...The reviving use of lithium metal anode(LMA)is one of the most promising ways to upgrade the energy density of lithium ion batteries.In the roadmap towards the real use,besides the formation of the dendrite,various adverse reactions due to the high activity of LMA when exposed to air or the electrolyte limit its practical applications.Learning from the packaging technology in electronic industry,we propose a wax-based coating compositing with the ion conducting poly(ethylene oxide)by a simple dip-coating technology and the prepared LMA is featured with an air-stable and waterproof surface.The LMA thus remains stable for 24 h in ambient air even with the relative humidity of 70% while retaining about85% its electrochemical capacity.More importantly,the LMA is accessible to water and when dipping in water,no obvious adverse reactions or capacity decay is observed.With the composite coating,a steady cycling performance for 500 h in symmetrical cells and a low capacity decay rate of 0.075% per cycle after 300 cycles in lithium-sulfur batteries assembled with the packaged anode have been achieved.This work demonstrates a very simple and effective LMA package technology which is easily scalable and is very promising for speeding up the industrialization of lithium-sulfur batteries and shows potentials for the large-scale production of air-sensitive electrode materials not limited to LMAs.展开更多
In recent years, the Vehicle-to-Vehicle(V2V) communication system has been considered one of the most promising technologies to build a much safer and more efficient transportation system. Both simulation and field te...In recent years, the Vehicle-to-Vehicle(V2V) communication system has been considered one of the most promising technologies to build a much safer and more efficient transportation system. Both simulation and field test have been extensively performed to evaluate the performance of the V2V communication system. However,most of the evaluation methods are communication-based, and although in a transportation environment, lack a V2V application-oriented analysis. In this study, we conducted real-world tests and built an application-oriented evaluation model. The experiments were classified into four scenarios: static, following, face 2 face, and crossing vertically, which almost covered all the V2V communication patterns on the road. Under these scenarios, we conducted experiments and built a probability model to evaluate the performance of 802.11p and LTE-V in safetyrelated applications. Consequently, we found out that improvements are still needed in Non-Line-of-Sight scenarios.展开更多
Developi ng alter native oxyge n reducti on reactio n (ORR) catalysts to replace precious Pt-based metals with abundant materials is the key challe nge of commercial application of fuel cells. Owing to their various c...Developi ng alter native oxyge n reducti on reactio n (ORR) catalysts to replace precious Pt-based metals with abundant materials is the key challe nge of commercial application of fuel cells. Owing to their various compositi ons and tun able electronic properties, transition metal dichalcogenides (TMDs) have the great potential to realize high-efficiency catalysts for ORR. Here, various 3R-phase dichalcogenides of group VB and VIB transition metals (MX2, M = Nb, Ta, Mo, W;X = S, Se, Te) are investigated for ORR catalysts by using density functional theory calculations. The computed over-potentials of group VB TMDs are much less than those of group VIB TMDs. For group VB TMDs, a volcano-type plot of ORR catalytic activity is established on the adsorption energies of *OH, and NbS2 and TaTe2 exhibit best ORR activity with an oveepotential of 0.54 V. To achieve even better activity, strain engineering is performed to tune ORR catalytic activity, and the minimum over-potential of 0.43 V can be realized. We further dem on strate that the shift of p orbital center of surface chalcoge n elements under strain is responsible for tuning the catalytic activity of TMDs.展开更多
基金support from Shenzhen Municipal Development and Reform Commission(Grant Number:SDRC[2016]172)Shenzhen Science and Technology Program(Grant No.KQTD20170810150821146)Interdisciplinary Research and Innovation Fund of Tsinghua Shenzhen International Graduate School,and Shanghai Shun Feng Machinery Co.,Ltd.
文摘It remains challenging to effectively estimate the remaining capacity of the secondary lithium-ion batteries that have been widely adopted for consumer electronics,energy storage,and electric vehicles.Herein,by integrating regular real-time current short pulse tests with data-driven Gaussian process regression algorithm,an efficient battery estimation has been successfully developed and validated for batteries with capacity ranging from 100%of the state of health(SOH)to below 50%,reaching an average accuracy as high as 95%.Interestingly,the proposed pulse test strategy for battery capacity measurement could reduce test time by more than 80%compared with regular long charge/discharge tests.The short-term features of the current pulse test were selected for an optimal training process.Data at different voltage stages and state of charge(SOC)are collected and explored to find the most suitable estimation model.In particular,we explore the validity of five different machine-learning methods for estimating capacity driven by pulse features,whereas Gaussian process regression with Matern kernel performs the best,providing guidance for future exploration.The new strategy of combining short pulse tests with machine-learning algorithms could further open window for efficiently forecasting lithium-ion battery remaining capacity.
基金funded by the National Key Research and Development Program of China(2017YFA0700103,2018YFA0704502)the National Natural Science Foundation of China(21703248)staffs in BL11B beamline in Shanghai Synchrotron Radiation Facility(SSRF)for their technical assistance(2020-SSRF-PT-012223 and 2021-SSRF-PT-015319)。
文摘The conversion of CO_(2)into value-added chemicals coupled with the storage of intermittent renewable electricity is attractive.CuO nanosheets with an average size and thickness of~30 and~20 nm have been developed,which are in situ reduced into Cu nanosheets during electrochemical CO_(2)reduction reaction(ECO_(2)RR).The derived Cu nanosheets demonstrate much higher selectivity for C2H4production than commercial CuO derived Cu powder,with an optimum Faradaic efficiency of 56.2%and a partial current density of C_(2)H_(4)as large as 171.0 mA cm^(-2)in a gas diffusion flow cell.The operando attenuated total reflectance-Fourier transform infrared spectra measurements and density functional theory simulations illustrate that the high activity and selectivity of Cu nanosheets originate from the edge sites on Cu nanosheets with a coordinate number around 5(4–6),which facilitates the formation of^(*)CHO rather than^(*)COH intermediate,meanwhile boosting the C-C coupling reaction of^(*)CO and^(*)CHO intermediates,which are the critical steps for C_(2)H_(4)formation.
文摘Objective To screen antigen targets for immunotherapy by analyzing over-expressed genes,and to identify significant pathways and molecular mechanisms in esophageal cancer by using bioinformatic methods such as enrichment analysis,protein-protein interaction(PPI)network,and survival analysis based on the Gene Expression Omnibus(GEO)database.Methods By screening with highly expressed genes,we mainly analyzed proteins MUC13 and EPCAM with transmembrane domain and antigen epitope from TMHMM and IEDB websites.Significant genes and pathways associated with the pathogenesis of esophageal cancer were identified using enrichment analysis,PPI network,and survival analysis.Several software and platforms including Prism 8,R language,Cytoscape,DAVID,STRING,and GEPIA platform were used in the search and/or figure creation.Results Genes MUC13 and EPCAM were over-expressed with several antigen epitopes in esophageal squamous cell carcinoma(ESCC)tissue.Enrichment analysis revealed that the process of keratinization was focused and a series of genes were related with the development of esophageal cancer.Four genes including ALDH3A1,C2,SLC6A1,and ZBTB7C were screened with significant P value of survival curve.Conclusions Genes MUC13 and EPCAM may be promising antigen targets or biomarkers for esophageal cancer.Keratinization may greatly impact the pathogenesis of esophageal cancer.Genes ALDH3A1,C2,SLC6A1,and ZBTB7C may play important roles in the development of esophageal cancer.
基金supported by the Shenzhen Science and Technology Innovation Commission Fundamental Research Key Projects(Nos.JCYJ20180508153013853,JCYJ20180508152130899)the Shenzhen Science and Technology Innovation Fund(No.JCYJ20150331142757381)the National Natural Science Foundation of China(Nos.81641051,81872368).
文摘Introduction:Sulfatase 2(SULF2),an endogenous extracellular sulfatase,can remove 6-O-sulfate groups of glucosamine residues from heparan sulfate(HS)chains to modulate the Wnt/β-catenin signaling pathway,which plays an important role in both liver carcinogenesis and embryogenesis.Side population(SP)cells are widely identified as stem-like cancer cells and are closely related to carcinoma metastasis,recurrence,and poor patient prognosis.However,the roles of SULF2 in SP cells of hepatomas are unclear,and the underlying mechanism is undefined.Objectives:This study aimed to compare the heterogeneity between SP cells and non-side population(NSP)cells derived from three different liver cancer cell lines and to elucidate the involvement of the SULF2-Wnt/β-catenin axis in liver cancer stem cells(CSCs)and its impact on the processes of carcinogenesis and invasiveness.Methods:In this work,three different liver cancer SP cells(HepG2,Huh7,and PRC/PRL/5)were sorted by flow cytometry.We also examined the migration and invasion behaviors of SP and NSP cells.To determine if this high tumorigenic potential of SP cells is correlated to SULF2,qPCR,western blotting,and immunofluorescence analysis were conducted.We also performed nude mouse xenograft experiments for in vivo analysis.Results:The results from the in vitro colony formation assay showed that SP cells exhibited a 2-fold higher colony formation efficiency compared to their NSP counterparts.The SP cells exhibited significantly higher potentials in terms of their migratory capacity and invasive ability compared to NSP cells.We found that higher expression of SULF2 in SP cells was associated with greater capabilities for clonogenicity,migration,and invasion.It was also linked to higher activation of the Wnt/β-catenin signaling pathway via stimulation of key downstream factors,particularlyβ-catenin,c-Myc,and cyclin D1.Further,a positive correlation between the upregulated SULF2 expression and tumorigenesis in the in vivo nude mouse xenograft models was demonstrated,highlighting that the potential underlying mechanism was Wnt/β-catenin signaling pathway activation.Conclusion:Our findings show that variable SULF2 expression was associated with differential activation of the Wnt/β-catenin signaling pathway,which could lead to behavioral differences between SP and NSP cells and also among the SP cells of the three liver cancer cell lines assessed.It was reasonably concluded that the SULF2-Wnt/β-catenin axis could play an important role in the tumorigenicity of liver cancer stem cells.
基金supported by the National Natural Science Foundation of China(Grant Nos.11774242,61605127,61975131,62175166,and 61335001)the Shenzhen Science and Technology Planning Project(Grant Nos.JCYJ20210324094200001,JCYJ20200109105411133,and ZDSYS20210623092006020).
文摘Fourier light-field microscopy(FLFM)uses a microlens aray(MLA)to segment the Fourierplane of the microscopic objective lens to generate multiple two-dimensional perspective views,thereby reconstructing the threedimensional(3D)structure of the sample using 3D deconvo-lution calculation without scanning.However,the resolution of FLFM is stil limited by dif-fraction,and furthermore,it is dependent on the aperture division.In order to improve itsresolution,a super-resolution opticai fuctuation Fourier light-field microscopy(SOFFLFM)wasproposed here,in which the super-resolution optical fluctuation imaging(SOFI)with the abilityof super-resolution was introduced into FLFM.SOFFLFM uses higher-order cumulants statis-tical analysis on an image sequence collected by FLFM,and then carries out 3D deconvolutioncalculation to reconstruct the 3D structure of the sample.The theoretical basis of SOFFLFM onimproving resolution was explained and then verified with the simulations.Simulation resultsdemonstrated that SOFFLFM improved the lateral and axial resolution by more than V2 and 2times in the second-and fourth-order accumulations,compared with that of FLFM.
基金supported by the Guangdong Natural Science Funds for Distinguished Young Scholar (2017B030306006)the National Natural Science Foundation of China (Nos. 51772164, U1601206 and U1710256)+2 种基金the National Key Basic Research Program of China (2014CB932400)the Shenzhen Technical Plan Project (Nos. KQJSCX20160226191136, JCYJ20150529164918734 and JCYJ20170412171630020)the Shenzhen Environmental Science and New Energy Technology Engineering Laboratory (No. SDRC [2016]172)
文摘Carbon materials are considered to be one of the most promising anode materials for sodium-ion batteries(SIBs),but the well-ordered graphitic structure limits the intercalation of sodium ions.Besides,the sluggish intercalation kinetics of sodium ions impedes the rate performance.Thus,the precise structure control of carbon materials is important to improve the battery performance.Herein,a 3D porous hard-soft composite carbon(3DHSC)was prepared using the NaCl as the template and phenolic resin and pitch as carbon precursors.The NaCl template restrains the growth of the graphite crystallite during the carbonization process,resulting in small graphitic domains with expanded interlayer spacing which is favorable for the sodium storage.Moreover,the Na Cl templates help to create abundant mesopores and macropores for fast sodium ion diffusion.The porous structure and the graphite crystalline structure can be precisely controlled by simply adjusting the mass ratio of Na Cl,and thus,the suitable structure can be prepared to reach high capacity and rate performance while keeping a relatively high Coulombic efficiency.Typically,a high reversible capacity(215 mA h g^(-1)at 0.05 A g^(-1)),an excellent rate capability(97 mA h g^(-1)at 5 A g^(-1)),and a high initial Coulombic efficiency(60%)are achieved.
基金supported by grants from the National Natural Science Foundation of China(Grant Nos.81972918 and 61971255)Shenzhen Science and Technology Innovation Committee(Grant No.KQJSCX20180327143623167)+2 种基金NANJING CHIA TAI TIANQING Company,Foundation for Young Innovative Talents in Education of Guangdong(Grant No.2017KQNCX161)Natural Science Foundation of Guangdong Province(Grant No.2018A030310249)Key Clinical Technique of Guangzhou(Grant No.2019ZD16)。
文摘Objective:Organoids have recently been used as in vitro models to screen chemotherapy drugs in combination with hyperthermia treatment in colorectal cancer.Our research aimed to establish a library of patient-derived colorectal cancer organoids to evaluate synergism between chemotherapy drugs and hyperthermia;validate an index of the hyperthermia chemotherapy sensitization enhancement ratio(HCSER)to identify the chemotherapeutics most enhanced by hyperthermia;and recommend chemotherapy drugs for hyperthermic intraperitoneal treatment.Methods:Organoids were grown from cells extracted from colorectal cancer patient samples or colorectal cancer cell lines.Cells from both sources were encapsulated in 3 D Matrigel droplets,which were formulated in microfluidics and phase-transferred into identical cell-laden Matrigel microspheres.The microspheres were seeded in 96-well plates,with each well containing a single microsphere that developed into an organoid after 7 days.The organoids were used to evaluate the efficacy of chemotherapy drugs at both 37℃ as a control and 43℃ for 90 min to examine hyperthermia synergism.Cell viability was counted with 10%CCK8.Results:We successfully established a library of colorectal cancer organoids from 22 patient parental tumors.We examined the hyperthermia synergism of 7 commonly used hyperthermic intraperitoneal chemotherapy drugs.In 11 of the 22 patient organoids,raltitrexed had significant hyperthermia synergism,which was indexed as the highest HCSER score within each patient group.Conclusions:Our results primarily demonstrated the use of patient-derived colorectal cancer organoids as in vitro models to evaluate hyperthermia synergistic chemotherapeutics.We found that hyperthermia enhanced the effect of raltitrexed the most among the common anti-colorectal cancer drugs.
基金The authors acknowledge support from the National Key Research and Development Program of China(no.2019YFD1000400)the National Natural Science Foundation of China(no.31700618)+2 种基金the Outstanding Young Scientific Research Talent Project of Fujian Agriculture and Forestry University(no.xjq201910)the Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilizati on Construction Funds(nos.115/118990050,115/KJG18016A)the Furopean Research Council(ERC)under the Furopean Union's Horizon 2020 research and innovation program(grant agreement No 833522).
文摘The marvelously diverse Orchidaceae constitutes the largest family of angiosperms.The genus Cymbidium in Orchidaceae is well known for its unique vegetation,floral morphology,and flower scent traits.Here,a chromosomescale assembly of the genome of Cymbidium ensifolium(Jianlan)is presented.Comparative genomic analysis showed that C.ensifolium has experienced two whole-genome duplication(WGD)events,the most recent of which was shared by all orchids,while the older event was the t event shared by most monocots.The results of MADS-box genes analysis provided support for establishing a unique gene model of orchid flower development regulation,and flower shape mutations in C.ensifolium were shown to be associated with the abnormal expression of MADS-box genes.The most abundant floral scent components identi fied included methyl jasmonate,acacia alcohol and linalool,and the genes involved in the floral scent component network of C.ensifolium were determined.Furthermore,the decreased expression of photosynthesis-antennae and photosynthesis metabolic pathway genes in leaves was shown to result in colorful striped leaves,while the increased expression of MADS-box genes in leaves led to perianth-like leaves.Our results provide fundamental insights into orchid evolution and diversi fication.
基金supported by the National Natural Science Foundation of China(NO.51977118)。
文摘Due to their outstanding anti-flashover characteristics,composite insulators have been extensively applied in power systems.A lot of research has investigated flashover characteristics of hydrophobic specimens with artificial water droplets.However,the phenomenon is not consistent with that of the contaminated composite insulators.On the test specimens covered with water droplets,there is no obvious leakage current before the flashover and no obvious relationship between flashover voltage and the conductivity of water droplets.On the contaminated composite insulator surface,there are short continuous arcs on the insulators before critical flashover,making insulators look like a luminous lantern.Considering that under these two conditions,the proportion of water along the insulation distance is different,the flashover characteristic of“dry band-water band”on a hydrophobicity surface is analyzed in the present study.The influence of the water band parameter(including length,width,and conductivity)as well as the length of dry band is studied.On this basis,the arc generation and development process of the surface covered with“dry band-water band”is analyzed.The research results improve the understanding of the flashover process on contaminated composite insulators.
基金Shenzhen Excellent Technological and Innovative Talent Training Project,Grant/Award Number:RCBS20200714114956357National Natural Science Youth Fund of China,Grant/Award Number:52007095National Natural Science Fund of China,Grant/Award Number:51907178。
文摘Composite insulators are generally considered to have excellent anti-pollution flashover performance,but recently there has been a flashover accident on the indoor clean insulator in China,which is suspected to be related to the wetting of insulators through condensation.Therefore,this paper studied the water condensation on hydrophobic surfaces.The changes in the mass,length,and proportion of the water droplets on the hydrophobic surface during the wetting process were measured,and the influence of wetting degree on the flashover characteristics was studied.It was found that the insulator surface temperature lower than the dew point is a prerequisite for the wetting of the clean hydrophobic surface,and the wetting velocity increases with the electric field.The results could provide some reference for understanding the insulator flashover accidents.
基金financially supported by the National Natural Science Foundation of China(Nos.22006088 and 42077293)the Natural Science Foundation of Guangdong Province(China)(No.2019QN01L797)+1 种基金the Shenzhen Municipal Science and Technology Innovation Committee(China)(Nos.WDZC20200817103015002 and RCYX20210609104448111)the Tsinghua Shenzhen International Graduate School(China)(Nos.HW2020002 and QD2021010N).
文摘Heterogeneous photocatalysis has gained substantial research interest in treating per-and polyfluoroalkyl substances(PFAS)-contaminated water.However,sluggish degradation kinetics and low defluorination efficiency compromise their practical applications.Here,we report a superior photocatalyst,defected Bi_(3)O(OH)(PO_(4))_(2),which could effectively degrade typical PFAS,perfluorooctanoic acid(PFOA),with high defluorination efficiency.The UV light irradiation could in situ generate oxygen vacancies on Bi_(3)O(OH)(PO_(4))_(2) through oxidation of the lattice hydroxyls,which further promotes the formation of Lewis acidic coordinately unsaturated bismuth sites.Then,the Lewis acidic sites couple with the proximal surface hydroxyls to constitute the surface frustrated Lewis pairs(SFLPs).With the in-depth spectroscopic analysis,we revealed that the photo-induced SFLPs act as collection centers to effectively adsorb PFOA and endow accessible pathways to transfer photogenerated holes to PFOA rapidly.Consequently,activation of the terminal carboxyl,a ratelimiting step for PFOA decomposition,could be easily achieved over the defected Bi_(3)O(OH)(PO_(4))_(2) photocatalyst.These results suggest that SFLPs exhibit great potential in developing highly efficient photocatalysts to degrade persistent organic pollutants.
基金supported by the National Natural Science Foundation of China(Nos.42077293,22006088)the Project of the Shenzhen Municipal Science and Technology Innovation Committee,China(No.RCYX20210609104448111)+1 种基金the Natural Science Foundation of Guangdong Province,China(No.2019QN01L797)the Project of the Tsinghua Shenzhen International Graduate School,China(Nos.HW2020002,QD2021010N).
文摘Microplastics(MPs)have been one of the most concerned environmental issues since the 21st century.MPs are plastic particles with diameters less than 5 mm,which are widely sourced in the aquatic environment.After being released into the aquatic environment,MPs would experience complicated physical,chemical and biological aging processes driven by mechanical forces,photooxidation,and biological degradation,which would result in changes in MPs’physicochemical properties,such as the particle size,specific surface area,hydrophobicity,crystallinity,etc.In this review,we have illustrated the current study status on MPs’environmental aging processes and pointed out the knowledge gaps.MPs’aging processes would consequentially influence MPs’interaction with the co-existing organic and inorganic pollutants in the aquatic environment as well as lead to the leaching of chemical additives involved in plastic production,including plasticizers and flame retardants,which can trigger high ecotoxicity to the aquatic environment.Furthermore,aged MPs would cause ecotoxicity to aquatic organisms via bioaccumulation,biomagnification,and indirect carrier pathways.The review would provide an in-depth overview of MPs’environmental aging processes and consequential ecotoxicity implications,as well as propose future research needs.
基金This work is financially supported by Shenzhen Science and Technology Innovation Committee(No.JCYJ20190809172615277)Guangdong Basic and Applied Basic Research Foundation(No.2020A1515111065)Shenzhen Municipal Development and Reform Commission,New Energy Technology Engineering Laboratory(No.SDRC[2016]172).
文摘Due to their excellent advantages such as low toxicity,superior optoelectronic properties,low-temperature fabrication,and costeffectiveness,Sn-based perovskites have become the most promising alternatives for high performance lead-free perovskite solar cells.However,the character of Sn ^(2+)is easily oxidized toSn ^(4+),causing unnecessary p-type self-doping and high leakage current.More seriously,trap-induced non-radiative recombination from rapid crystallization causes into large energy loss with a low open circuit voltage.Therefore,the Sn-based solar cells have efficiency far behind the Pb-based solar cells.Herein,the polymer poly(ethylene glycol)diacrylate(PEGDA)is used to control crystal growth and passivate the defects in FA_(0.85)PEA_(0.15)SnI_(3) thin film.This Sn-perovskite layer shows compact crystal with large grain size and reduced defects.Optimized perovskite thin film is further processed to fabricate the inverted solar cell with device structure of ITO(indium tin oxide)/PEDOT:PSS(Poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate))/FA_(0.85)PEA_(0.15)SnI_(3)/ICBA(indene-C60 bisadduct)/BCP(bathocuproine)/Ag,which shows the power conversion efficiency(PCE)of 11.45%with voltage of 0.82 V.Moreover,corresponding perovskite solar cells exhibit an enhanced stability due to PEGDA induced compressive strain in perovskite.This work could shed light on one of successful attempts to improve Sn-based solar cell efficiency for sustainable energy conversion.
基金supported in part by the National Key Research and Development(No.2021YFB2501200).
文摘Virtual simulation testing of Autonomous Vehicles(AVs)is gradually being accepted as a mandatory way to test the feasibility of driving strategies for AVs.Mainstream methods focus on improving testing efficiency by extracting critical scenarios from naturalistic driving datasets.However,the criticalities defined in their testing tasks are based on fixed assumptions,the obtained scenarios cannot pose a challenge to AVs with different strategies.To fill this gap,we propose an intelligent testing method based on operable testing tasks.We found that the driving behavior of Surrounding Vehicles(SVs)has a critical impact on AV,which can be used to adjust the testing task difficulty to find more challenging scenarios.To model different driving behaviors,we utilize behavioral utility functions with binary driving strategies.Further,we construct a vehicle interaction model,based on which we theoretically analyze the impact of changing the driving behaviors on the testing task difficulty.Finally,by adjusting SV’s strategies,we can generate more corner cases when testing different AVs in a finite number of simulations.
基金the financial support from the Guangdong Natural Science Funds for Distinguished Young Scholar (2017B030306006) the National Natural Science Foundation of China (51772164, U1601206 and U1710256)+1 种基金 the National Key Basic Research Program of China (2014CB932400)Shenzhen Technical Plan Project (JCYJ20150529164918734 and JCYJ20170412171359175)
基金supported by the National Key Research and Development Program of China (2016YBF0100100, 2016YFA0200101, and 2016YFA0200200)the National Natural Science Foundation of China (51572259, 51325205, 51290273, and 51521091)+3 种基金the Natural Science Foundation of Liaoning Province (201602737)the Thousand Youth Talents Plan of China (Y5610121T3)China Postdoctoral Science Foundation (2016M601349)dedicated funds for methanol conversion from Dalian Institute of Chemical Physics, Chinese Academy of Sciences
文摘Graphene, with unique two-dimensional form and numerous appealing properties, promises to remarkably increase the energy density and power density of electrochemical energy storage devices(EESDs),ranging from the popular lithium ion batteries and supercapacitors to next-generation high-energy batteries. Here, we review the recent advances of the state-of-the-art graphene-based materials for EESDs,including lithium ion batteries, supercapacitors, micro-supercapacitors, high-energy lithium-air and lithium-sulfur batteries, and discuss the importance of the pore, doping, assembly, hybridization and functionalization of different nano-architectures in improving electrochemical performance. The major roles of graphene are highlighted as(1) a superior active material,(2) ultrathin 2D flexible support,and(3) an inactive yet electrically conductive additive. Furthermore, we address the enormous potential of graphene for constructing new-concept emerging graphene-enabled EESDs with multiple functionalities of lightweight, ultra-flexibility, thinness, and novel cell configurations. Finally, future perspectives and challenges of graphene-based EESDs are briefly discussed.
基金supported by the National Key Research and Development Program of China(2016YFA0200101)the National Natural Science Foundation of China(51325205,51290273,and51521091)Chinese Academy of Sciences(KGZD-EW-303-1,KGZDEW-T06,174321KYSB20160011,and XDPB06)
文摘Tailoring the pore structure and surface chemistry of graphene-based laminates is essentially important for their applications as separation membranes.Usually,pure graphene oxide(GO) and completely reduced GO(r GO) membranes suffer from low water permeance because of the lack of pristine graphitic sp^2 domains and very small interlayer spacing,respectively.In this work,we studied the influence of reduction degree on the structure and separation performance of r GO membranes.It was found that weak reduction retains the good dispersion and hydrophilicity of GO nanosheets.More importantly,it increases the number of pristine graphitic sp^2 domains in rGO nanosheets while keeping the large interlayer spacing of the GO membranes in most regions at the same time.The resultant membranes show a high water permeance of 56.3 L m^(-2)h^(-1)bar^(-1),which is about 4 times and over 10~4 times larger than those of the GO and completely reduced r GO membranes,respectively,and high rejection over 95% for various dyes.Furthermore,they show better structure stability and more superior separation performance than GO membranes in acid and alkali environments.
基金supported by the National Science Fund for Distinguished Young Scholars, China (51525204)National Natural Science Foundation of China (51772164 and U1601206)+3 种基金Guangdong Natural Science Funds for Distinguished Young Scholar (2017B030306006)Guangdong Special Support Program (2017TQ04C664)the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program (2017BT01N111)the Shenzhen Basic Research Project (JCYJ20170412171630020 and JCYJ20170412171359175)
文摘The reviving use of lithium metal anode(LMA)is one of the most promising ways to upgrade the energy density of lithium ion batteries.In the roadmap towards the real use,besides the formation of the dendrite,various adverse reactions due to the high activity of LMA when exposed to air or the electrolyte limit its practical applications.Learning from the packaging technology in electronic industry,we propose a wax-based coating compositing with the ion conducting poly(ethylene oxide)by a simple dip-coating technology and the prepared LMA is featured with an air-stable and waterproof surface.The LMA thus remains stable for 24 h in ambient air even with the relative humidity of 70% while retaining about85% its electrochemical capacity.More importantly,the LMA is accessible to water and when dipping in water,no obvious adverse reactions or capacity decay is observed.With the composite coating,a steady cycling performance for 500 h in symmetrical cells and a low capacity decay rate of 0.075% per cycle after 300 cycles in lithium-sulfur batteries assembled with the packaged anode have been achieved.This work demonstrates a very simple and effective LMA package technology which is easily scalable and is very promising for speeding up the industrialization of lithium-sulfur batteries and shows potentials for the large-scale production of air-sensitive electrode materials not limited to LMAs.
基金supported in part by the National Natural Science Foundation of China(No.61673233)Beijing Municipal Science and Technology Program(No.D15110900280000)+1 种基金subsidized by the standardization and new model for intelligent manufacture:Research and Test Platform of System and Communication Standardization for Intelligent and Connected Vehicle(No.2016ZXFB06002)Shanghai International Automobile City
文摘In recent years, the Vehicle-to-Vehicle(V2V) communication system has been considered one of the most promising technologies to build a much safer and more efficient transportation system. Both simulation and field test have been extensively performed to evaluate the performance of the V2V communication system. However,most of the evaluation methods are communication-based, and although in a transportation environment, lack a V2V application-oriented analysis. In this study, we conducted real-world tests and built an application-oriented evaluation model. The experiments were classified into four scenarios: static, following, face 2 face, and crossing vertically, which almost covered all the V2V communication patterns on the road. Under these scenarios, we conducted experiments and built a probability model to evaluate the performance of 802.11p and LTE-V in safetyrelated applications. Consequently, we found out that improvements are still needed in Non-Line-of-Sight scenarios.
基金National Key Research and Development Program of China (No. 2017YFB0701600)National Natural Science Foundation of China (Nos. 11874036, 51622103, and 21573123)+2 种基金Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program (No. 2017BT01N111)Shenzhen Projects for Basic Research (No. JCYJ20170412171430026)National Program for Thousand Young Talents of China.
文摘Developi ng alter native oxyge n reducti on reactio n (ORR) catalysts to replace precious Pt-based metals with abundant materials is the key challe nge of commercial application of fuel cells. Owing to their various compositi ons and tun able electronic properties, transition metal dichalcogenides (TMDs) have the great potential to realize high-efficiency catalysts for ORR. Here, various 3R-phase dichalcogenides of group VB and VIB transition metals (MX2, M = Nb, Ta, Mo, W;X = S, Se, Te) are investigated for ORR catalysts by using density functional theory calculations. The computed over-potentials of group VB TMDs are much less than those of group VIB TMDs. For group VB TMDs, a volcano-type plot of ORR catalytic activity is established on the adsorption energies of *OH, and NbS2 and TaTe2 exhibit best ORR activity with an oveepotential of 0.54 V. To achieve even better activity, strain engineering is performed to tune ORR catalytic activity, and the minimum over-potential of 0.43 V can be realized. We further dem on strate that the shift of p orbital center of surface chalcoge n elements under strain is responsible for tuning the catalytic activity of TMDs.