We report a facile way to grow various porous NiO nanostructures including nanoslices,nanoplates,and nanocolumns,which show a structure-dependence in their specific charge capacitances.The formation of controllable po...We report a facile way to grow various porous NiO nanostructures including nanoslices,nanoplates,and nanocolumns,which show a structure-dependence in their specific charge capacitances.The formation of controllable porosity is due to the dehydration and re-crystallization of β-Ni(OH)_(2) nanoplates synthesized by a hydrothermal process.Thermogravimetric analysis shows that the decomposition temperature of the β-Ni(OH)_(2) nanostructures is related to their morphology.In electrochemical tests,the porous NiO nanostructures show stable cycling performance with retention of specific capacitance over 1000 cycles.Interestingly,the formation of nanocolumns by the stacking of β-Ni(OH)_(2) nanoslices/plates favors the creation of small pores in the NiO nanocrystals obtained after annealing,and the surface area is over five times larger than that of NiO nanoslices and nanoplates.Consequently,the specific capacitance of the porous NiO nanocolumns(390 F/g)is significantly higher than that of the nanoslices(176 F/g)or nanoplates(285 F/g)at a discharge current of 5 A/g.This approach provides a clear illustration of the process-structure-property relationship in nanocrystal synthesis and potentially offers strategies to enhance the performance of supercapacitor electrodes.展开更多
Online fault detection is one of the key technologies to improve the performance of cloud systems. The current data of cloud systems is to be monitored, collected and used to reflect their state. Its use can potential...Online fault detection is one of the key technologies to improve the performance of cloud systems. The current data of cloud systems is to be monitored, collected and used to reflect their state. Its use can potentially help cloud managers take some timely measures before fault occurrence in clouds. Because of the complex structure and dynamic change characteristics of the clouds, existing fault detection methods suffer from the problems of low efficiency and low accuracy. In order to solve them, this work proposes an online detection model based on asystematic parameter-search method called SVM-Grid, whose construction is based on a support vector machine(SVM). SVM-Grid is used to optimize parameters in SVM. Proper attributes of a cloud system's running data are selected by using Pearson correlation and principal component analysis for the model. Strategies of predicting cloud faults and updating fault sample databases are proposed to optimize the model and improve its performance.In comparison with some representative existing methods, the proposed model can achieve more efficient and accurate fault detection for cloud systems.展开更多
As a future energy system,the smart grid is designed to improve the efficiency of traditional power systems while providing more stable and reliable services.However,this efficient and reliable service relies on colle...As a future energy system,the smart grid is designed to improve the efficiency of traditional power systems while providing more stable and reliable services.However,this efficient and reliable service relies on collecting and analyzing users’electricity consumption data frequently,which induces various security and privacy threats.To address these challenges,we propose a double-blockchain assisted secure and anonymous data aggregation scheme for fog-enabled smart grid named DA-SADA.Specifically,we design a three-tier architecture-based data aggregation framework by integrating fog computing and the blockchain,which provides strong support for achieving efficient and secure data collection in smart grids.Subsequently,we develop a secure and anonymous data aggregation mechanism with low computational overhead by jointly leveraging the Paillier encryption,batch aggregation signature and anonymous authentication.In particular,the system achieves fine-grained data aggregation and provides effective support for power dispatching and price adjustment by the designed double-blockchain and two-level data aggregation.Finally,the superiority of the proposed scheme is illustrated by a series of security and computation cost analyses.展开更多
The demand for high-performance non-precious-metal electrocatalysts to replace the noble metal-based catalysts for oxygen reduction reaction(ORR)is intensively increasing.Herein,single-atomic copper sites supported on...The demand for high-performance non-precious-metal electrocatalysts to replace the noble metal-based catalysts for oxygen reduction reaction(ORR)is intensively increasing.Herein,single-atomic copper sites supported on N-doped three-dimensional hierarchically porous carbon catalyst(Cu_(1)/NC)was prepared by coordination pyrolysis strategy.Remarkably,the Cu_(1)/NC-900 catalyst not only exhibits excellent ORR performance with a half-wave potential of 0.894 V(vs.RHE)in alkaline media,outperforming those of commercial Pt/C(0.851 V)and Cu nanoparticles anchored on N-doped porous carbon(CuNPs/NC-900),but also demonstrates high stability and methanol tolerance.Moreover,the Cu_(1)/NC-900 based Zn-air battery exhibits higher power density,rechargeability and cyclic stability than the one based on Pt/C.Both experimental and theoretical investigations demonstrated that the excellent performance of the as-obtained Cu_(1)/NC-900 could be attributed to the synergistic effect between copper coordinated by three N atoms active sites and the neighbouring carbon defect,resulting in elevated Cu d-band centers of Cu atoms and facilitating intermediate desorption for ORR process.This study may lead towards the development of highly efficient non-noble metal catalysts for applications in electrochemical energy conversion.展开更多
In order to prevent the microwave leakage and mutual interference,more and more microwave absorbing devices are added into the design of electronic products to ensure its routine operation.In this work,we have success...In order to prevent the microwave leakage and mutual interference,more and more microwave absorbing devices are added into the design of electronic products to ensure its routine operation.In this work,we have successfully prepared MoS_(2)/TiO_(2)/Ti_(3)C_(2)T_(x) hierarchical composites by one-pot hydrothermal method and focused on the relationship between structures and electromagnetic absorbing properties.Supported by comprehensive characterizations,M0S_(2) nanosheets were proved to be anchored on the surface and interlayer of Ti_(3)C_(2)T_(x) through a hydrothermal process.Additionally,TiO_(2) nanoparticles were obtained in situ.Due to these hierarchical structures,the MoS_(2)/TiO_(2)/Ti_(3)C_(2)T_(x) composites showed greatly enhanced microwave absorbing performance.The MoS_(2)/TiO_(2)/Ti_(3)C_(2)T_(x) composites exhibit a maximum reflection loss value of -33.5 dB at 10.24 GHz and the effective absorption bandwidth covers 3.1GHz(13.9-17 GHz)at the thickness of 1.0 mm,implying the features of wide frequency and light weight.This work in the hierarchical structure of MoS_(2)/TiO_(2)/Ti_(3)C_(2)T_(x) composites opens a promising door to the exploration of constructing extraordinary electromagnetic wave absorbents.展开更多
This paper investigates the problem of outlier-resistant distributed fusion filtering(DFF)for a class of multi-sensor nonlinear singular systems(MSNSSs)under a dynamic event-triggered scheme(DETS).To relieve the effec...This paper investigates the problem of outlier-resistant distributed fusion filtering(DFF)for a class of multi-sensor nonlinear singular systems(MSNSSs)under a dynamic event-triggered scheme(DETS).To relieve the effect of measurement outliers in data transmission,a self-adaptive saturation function is used.Moreover,to further reduce the energy consumption of each sensor node and improve the efficiency of resource utilization,a DETS is adopted to regulate the frequency of data transmission.For the addressed MSNSSs,our purpose is to construct the local outlier-resistant filter under the effects of the measurement outliers and the DETS;the local upper bound(UB)on the filtering error covariance(FEC)is derived by solving the difference equations and minimized by designing proper filter gains.Furthermore,according to the local filters and their UBs,a DFF algorithm is presented in terms of the inverse covariance intersection fusion rule.As such,the proposed DFF algorithm has the advantages of reducing the frequency of data transmission and the impact of measurement outliers,thereby improving the estimation performance.Moreover,the uniform boundedness of the filtering error is discussed and a corresponding sufficient condition is presented.Finally,the validity of the developed algorithm is checked using a simulation example.展开更多
Thc main aim of this paper is to use the continuation theorem of coincidence degree theory for studying the existence of periodic solutions to a kind of neutral functional differential equation as follows：（x（t）-^n...Thc main aim of this paper is to use the continuation theorem of coincidence degree theory for studying the existence of periodic solutions to a kind of neutral functional differential equation as follows：（x（t）-^n∑i=1cix（t-ri））″=f（x（t））x′＋g（x（t-τ））＋p（t）.In order to do so, we analyze the structure of the linear difference operator A ： C2π→C2π, [Ax]（t） =x（t）-∑^ni=1cix（t-ri）to determine some flmdamental properties first, which we are going to use throughout this paper. Meanwhile, we also prove some new inequalities which are useful for estimating a priori bounds of periodie solutions.展开更多
Rapid development of solid-state lighting technology requires new materials with highly efficient and stable luminescence,and especially relies on blue light pumped red phosphors for improved light quality.Herein,we d...Rapid development of solid-state lighting technology requires new materials with highly efficient and stable luminescence,and especially relies on blue light pumped red phosphors for improved light quality.Herein,we discovered an unprecedented red-emitting Mg_(2)AI_(4)Si_(5)0_(18):Eu^(2+)composite phosphor(λex=450 nm,λem=620 nm)via the crystallization of MgO-AI_(2)O_(3)-Sio_(2) aluminosilicate glass.Combined experimental measurement and first-principles calculations verify that Eu^(2+)dopants insert at the vacant channel of Mg_(2)AI_(4)Si_(5)0_(18)crystal with six-fold coordination responsible for the peculiar red emission.Importantly,the resulting phosphor exhibits high internal/external quantum efficiency of 94.5/70.6%,and stable emission against thermal quenching,which reaches industry production.The maximum luminous flux and luminous efficiency of the constructed laser driven red emitting device reaches as high as 274 Im and 54lm W^(-1),respectively.The combinations of extraordinary optical properties coupled with economically favorable and innovative preparation method indicate,that the Mg_(2)AI_(4)Si_(5)0_(18):Eu^(2+)composite phosphor will provide a significant step towards the development of high-power solid-state lighting.展开更多
In this paper,the recursive filtering problem is considered for stochastic systems over filter-and-forward successive relay(FFSR)networks.An FFSR is located between the sensor and the remote filter to forward the meas...In this paper,the recursive filtering problem is considered for stochastic systems over filter-and-forward successive relay(FFSR)networks.An FFSR is located between the sensor and the remote filter to forward the measurement.In the successive relay,two cooperative relay nodes are adopted to forward the signals alternatively,thereby existing switching characteristics and inter-relay interferences(IRI).Since the filter-and-forward scheme is employed,the signal received by the relay is retransmitted after it passes through a linear filter.The objective of the paper is to concurrently design optimal recursive filters for FFSR and stochastic systems against switching characteristics and IRI of relays.First,a uniform measurement model is proposed by analyzing the transmission mechanism of FFSR.Then,novel filter structures with switching parameters are constructed for both FFSR and stochastic systems.With the help of the inductive method,filtering error covariances are presented in the form of coupled difference equations.Next,the desired filter gain matrices are further obtained by minimizing the trace of filtering error covariances.Moreover,the stability performance of the filtering algorithm is analyzed where the uniform bound is guaranteed on the filtering error covariance.Finally,the effectiveness of the proposed filtering method over FFSR is verified by a three-order resistance-inductance-capacitance circuit system.展开更多
The effects of laser parameters and interlayer material on the microstructure and properties of the welded joint between 6061 aluminum alloy and stainless steel were studied.The results show that the density and micro...The effects of laser parameters and interlayer material on the microstructure and properties of the welded joint between 6061 aluminum alloy and stainless steel were studied.The results show that the density and microstructure of the welded joint can be optimized by changing the laser power with 0.05 mm Cu foil and 0.1 mm Ni foil as interlayer.A large number of new Cu-Al binary phases were found near the aluminum alloy,which effectively inhibited the formation of the binary brittle phase of Fe-Al.The maximum shear force of 1350.96 N was obtained with laser power of 2200 W.The shear force of the welded joint increased to 1754.73 N when the thickness of the Cu foil thickness changed to 0.02 mm.展开更多
Rare earth co-doped phosphor for fluorescence intensity ratio(FIR) thermometer has gained increasing attention in recent years. Herein, the novel Tb^(3+)and Eu^(3+)co-doped K_(3)SrBi(P_(2)O_(7))_(2)(KSBP) phosphate ph...Rare earth co-doped phosphor for fluorescence intensity ratio(FIR) thermometer has gained increasing attention in recent years. Herein, the novel Tb^(3+)and Eu^(3+)co-doped K_(3)SrBi(P_(2)O_(7))_(2)(KSBP) phosphate phosphors were reported. The crystal structure of the title phosphor was determined using Rietveld refinement and proved to have a three-dimensional structure. The time-resolved spectroscopy reveals that there is almost no energy transfer between Tb^(3+)and Eu^(3+). More importantly, Tb^(3+)and Eu^(3+)emissions show different thermal quenching behaviors, which claims the potential of this material for application in optical thermometer. The FIR of the typical KSBP:0.02Tb^(3+),0.04Eu^(3+)sample demonstrates a polynomial relationship as a function of temperature and the absolute and relative sensitivity are0.025 K^(-1) and 0.59%/K, respectively. In general, our study reports a novel and potential KSBP:Tb^(3+),Eu^(3+)phosphate phosphor that is promising for use in high-sensitive FIR thermometers.展开更多
Over the past few decades,photocatalysis technology has received extensive attention because of its potential to mitigate or solve energy and environmental pollution problems.Designing novel materials with outstanding...Over the past few decades,photocatalysis technology has received extensive attention because of its potential to mitigate or solve energy and environmental pollution problems.Designing novel materials with outstanding photocatalytic activities has become a research hotspot in this field.In this study,we prepared a series of photocatalysts in which BiOCl nanosheets were modified with carbon quantum dots(CQDs)to form CQDs/BiOCl composites by using a simple solvothermal method.The photocatalytic performance of the resulting CQDs/BiOCl composite photocatalysts was assessed by rhodamine B and tetracycline degradation under visible-light irradiation.Compared with bare BiOCl,the photocatalytic activity of the CQDs/BiOCl composites was significantly enhanced,and the 5 wt%CQDs/BiOCl composite exhibited the highest photocatalytic activity with a degradation efficiency of 94.5%after 30 min of irradiation.Moreover,photocatalytic N_(2)reduction performance was significantly improved after introducing CQDs.The 5 wt%CQDs/BiOCl composite displayed the highest photocatalytic N_(2)reduction performance to yield NH_3(346.25μmol/(g h)),which is significantly higher than those of 3 wt%CQDs/BiOCl(256.04μmol/(g h)),7 wt%CQDs/BiOCl(254.07μmol/(g h)),and bare BiOCl(240.19μmol/(g h)).Our systematic characterizations revealed that the key role of CQDs in improving photocatalytic performance is due to their increased light harvesting capacity,remarkable electron transfer ability,and higher photocatalytic activity sites.展开更多
To explore the law of energy evolution and the change of damage before and after specimen failure,the conventional triaxial compression tests(5,10,15,20,and 30 MPa)of basalt fiber reinforced concrete(BFRC)with differe...To explore the law of energy evolution and the change of damage before and after specimen failure,the conventional triaxial compression tests(5,10,15,20,and 30 MPa)of basalt fiber reinforced concrete(BFRC)with different fiber volume fractions(0,0.2%and 0.4%)were carried out by MTS816 rock testing system,and the cyclic loading and unloading tests of BFRC with a fiber content of 0.2%were carried out.The experimental results show that the peak strength and strain of BFRC increase with the increase of confining pressure.Tensile failure occurs under low confining pressure,and shear failure occurs under high confining pressure.The best volume fraction of fiber is 0.2%.Under different confining pressures,the input energy,elastic energy,plastic properties,and dissipated energy of the samples first increase and then decrease to a stable level.The elastic energy and dissipated energy reach the maximum near the peak stress,while the input energy and plastic properties reach the maximum at the peak.At the same time,the damage increases continuously with the input of load under different confining pressures,indicating that the failure of the specimen is a process of energy accumulation.展开更多
Atomic non-noble metal materials show the potential to substitute noble metals in catalysis.Herein,melamine formaldehyde resin is developed to synthesize atomic iron on mesoporous nitrogen-doped carbon.The triazine un...Atomic non-noble metal materials show the potential to substitute noble metals in catalysis.Herein,melamine formaldehyde resin is developed to synthesize atomic iron on mesoporous nitrogen-doped carbon.The triazine units with abundant nitrogen content and cavity can realize effectively anchoring of single metal atoms.The atomic iron with unique charge and coordination characteristics shows superior catalytic performance in dehydrogenation reaction.Various N-heterocycles compounds and amines can be efficiently dehydrogenated into the corresponding products at room temperature,which is the mildest of all reported reaction conditions even when noble metal catalysts are considered.Therefore,development of atomic non-noble metal catalysts with mesoporous structure may provide an effective way to realize the substitution for noble metals in heterogeneous catalysis.展开更多
Very recently, the local coordination environment of active sites has been found to strongly influence their performance in electrocatalytic CO_(2) reduction by tuning the intrinsic kinetics of CO_(2) activation and i...Very recently, the local coordination environment of active sites has been found to strongly influence their performance in electrocatalytic CO_(2) reduction by tuning the intrinsic kinetics of CO_(2) activation and intermediate stabilization. It is imperative to elucidate the mechanism for such an influence towards the rational design of efficient catalysts;however, the complex interactions between the multiple factors involved in the system make it challenging to establish a clear structure–performance relationship. In this work, we chose ion-intercalated silver(I)-based coordination networks(AgCNs) with a well-defined structure as a model platform, which enables us to understand the regulation mechanism of counterions as the counterions are the only tuning factor involved in such a system. We prepared two isostructural Ag CNs with different intercalation ions or counterions of BF_(4)^(-) and ClO_(4)^(-)(named as AgCNs-BF_(4) and AgCNs-ClO_(4)) and found that the former has a more competitive CO_(2) electroreduction performance than the latter. AgCNs-BF_(4) achieves the highest Faradaic efficiency for CO_(2) to CO of 87.1% at-1.0 V(vs. RHE) with a higher partial current density, while AgCNs-ClO_(4) exhibits only 77.2% at the same applied potential.Spectroscopic characterizations and theoretical calculation reveal that the presence of BF_(4)^(-)is more favorable for stabilizing the COOH^(*) intermediate by weakening hydrogen bonds, which accounts for the superior activity of Ag CNs-BF_(4).展开更多
Dual-active sites(DASs)catalysts have positive potential applications in broad fields because of their specific active sites and synergistic catalytic effects.Therefore,the controllable synthesis and finely regulating...Dual-active sites(DASs)catalysts have positive potential applications in broad fields because of their specific active sites and synergistic catalytic effects.Therefore,the controllable synthesis and finely regulating the activity of such catalysts has become a hot research area for now.In this work,we developed a pyrolysis-etching-hydrogen activation strategy to prepare the DASs catalysts involving single-atom Cu and B on N-doped porous carbon material(Cu_(1)-B/NPC).Numerous systematic characterization and density functional theoretical(DFT)calculation results showed that the Cu and B existed as Cu-N4 porphyrinlike unit and B-N_(3)unit in the obtained catalyst.DFT calculations further revealed that single-atom Cu and B sites were linked by bridging N atoms to form the Cu_(1)-B-N6 dual-sites.The Cu_(1)-B/NPC catalyst was more effective than the single-active site catalysts with B-N_(3)sites in NPC(B/NPC)and Cu-N4 porphyrin-like sites in NPC(Cu_(1)/NPC),respectively,for the dehydrogenative coupling of dimethylphenylsilane(DiMPSH)with various alcohols,performing the great activity(>99%)and selectivity(>99%).The catalytic performances of the Cu_(1)-B/NPC catalyst remained nearly unchanged after five cycles,also indicating its outstanding recyclability.DFT calculations showed that the Cu_(1)-B-N6 dual-sites exhibited the lowest energy profile on the potential energy surface than that of sole B-N_(3)and Cu-N4 porphyrin-like sites.Furthermore,the rate-limiting step of dehydrogenation of DiMPSH on Cu_(1)-B-N6 dual-sites also showed a much lower activation energy than the other two single sites.Benefitting from the superiority of the Cu_(1)-B-N6 dual-sites,the Cu_(1)-B/NPC catalyst can also be used for CO_(2)electroreduction to produce syngas.Thus,DASs catalysts are promising to achieve multifunctional catalytic properties and have aroused positive attention in the field of catalysis.展开更多
Plasmon-generated hot electrons show great potential for driving chemical reactions.The utilization efficiency of hot electrons is highly dependent on the interaction of the electronic states at the interfaces between...Plasmon-generated hot electrons show great potential for driving chemical reactions.The utilization efficiency of hot electrons is highly dependent on the interaction of the electronic states at the interfaces between plasmonic nanoparticles and other materials/molecules.Strong interaction can produce new hybridized electron states,which permit direct hot-electron transfer,a more efficient transfer mechanism.However,Au usually has very weak interaction with most molecules because of its inertness,which makes direct hot-electron transfer impossible.Herein,the improvement of the hot-electron transfer efficiency from Au to N_(2)is demonstrated by introducing a Ru bridging layer.Both the N_(2)fixation rate and Faradic efficiency(FE)are enhanced by the excitation of plasmons.The enhancement of the N_(2)fixation rate is found to arise from plasmon-generated hot electrons.Theoretical calculations show that the strong interaction of the Ru electronic states with the N_(2)molecular orbitals produces new hybridized electronic states,and the Ru d electrons also strongly couple with the Au sp electrons.Such a bridging role of Ru makes direct hot-electron transfer from Au to N_(2)possible,improving the FE of nitrogen fixation.Our findings demonstrate a new approach to increasing the utilization efficiency of plasmonic hot electrons for chemical reactions and will be helpful to the design of plasmonic catalysts in the future.展开更多
Variations in the pathogenicity of Newcastle disease virus(NDV),the agent causing Newcastle disease,are associated with variants of different virulence.A few studies have characterized the expression of microRNAs(miRN...Variations in the pathogenicity of Newcastle disease virus(NDV),the agent causing Newcastle disease,are associated with variants of different virulence.A few studies have characterized the expression of microRNAs(miRNAs)in NDV-infected avian cells.Here,the expression of miRNAs in chicken embryo fibroblasts(CEFs)infected with Herts/33 and LaSota NDV strains(highly virulent and nonvirulent,respectively)was determined using RNA sequencing.miRNAs involved in NDV infection included 562 previously documented and 184 novel miRNAs.miRNA target genes involved transcription factors,cell apoptosis,ubiquitin-mediated proteolysis,and protein processing in the endoplasmic reticulum.Potential target genes associated with autophagy were verified by qRT-PCR.No studies have documented the miRNA profles of CEFs infected with NDVs variants.This study adds to our knowledge of the cellular miRNAs involved in NDV infection and the complex molecular mechanisms mediating virus-host interactions.The results of this study will aid the development of strategies against the chicken virus.展开更多
It is significant to optimize geometric configuration of metal catalytic sites and boost their catalytic activity.Herein,we synthesized isolated single Zn-N_(4)sites on N-doped carbon(Zn-CN)by pyrolyzing zeolite imida...It is significant to optimize geometric configuration of metal catalytic sites and boost their catalytic activity.Herein,we synthesized isolated single Zn-N_(4)sites on N-doped carbon(Zn-CN)by pyrolyzing zeolite imidazole framework-8(ZIF-8)at different temperatures.For the reciprocal transformation between benzyl alcohol and benzaldehyde,the catalytic activities of Zn-CN catalysts exhibited a volcano-like trend as the pyrolysis temperatures increased.The optimal catalyst was Zn-CN-900,with outstanding catalytic activity exceeding commercial 20 wt.%Pd/C and 20 wt.%Pt/C,promising to substitute the noble metalbased catalysts.X-ray absorption near-edge structure(XANES)measurements and density functional theory(DFT)calculation revealed the gradual transformation from tetrahedral ZnN_(4)sites of ZIF-8 into planar ZnN_(4)sites above 700℃,with the maximum planar ZnN_(4)sites in Zn-CN-900.The stronger adsorption between reactants and planar ZnN_(4)sites facilitated the activation of reactants compared with tetrahedral ZnN_(4)sites.This work will provide valuable insight into rational design of efficient catalysts by optimizing geometric configuration of catalytic sites.展开更多
In comparison to the traditional fixed-angle trajectory,the variable-angle trajectory has a greater design space.However,it is a challenge to determine which common design curve structure is the most effective for imp...In comparison to the traditional fixed-angle trajectory,the variable-angle trajectory has a greater design space.However,it is a challenge to determine which common design curve structure is the most effective for improving mechanical performance.This work explores the effects of various design curves such as fixed-angle curve,linear curve,arc curve,sine curve,Bezier curve,and cubic polynomial curve trajectories on mechanical performance of laminates,including vibration modal performance and buckling performance.Genetic algorithm and improved NSGA-II algorithm are then used to optimize various curve structures.The results are confirmed utilizing thermoplastic Carbon Fiber(CF)/Polyether-Ether-Ketone(PEEK)laminates made by robotic fiber placement experiments.The relationship model between different mechanical performance and curve design variables is established.The optimization of variable-angle structure with mechanical properties as input variables is achieved.Meanwhile,a full-process angle-variable laying software platform from trajectory planning(CAD),trajectory optimization to manufacturing(CAM)is developed for facilitating the fiber placement application.展开更多
基金The authors gratefully acknowledge the AcRF Tier 1 RG 31/08 from Ministry of Education Singapore and No.NRF2009EWT-CERP001-026 Singaporethe National Natural Science Foundation of China(No.20901003)+1 种基金the Natural Science Foundation of the Educational Department of Anhui Province(No.KJ2008B167)the Young Teacher Program of Anhui Normal University(No.2009xqnzc19).
文摘We report a facile way to grow various porous NiO nanostructures including nanoslices,nanoplates,and nanocolumns,which show a structure-dependence in their specific charge capacitances.The formation of controllable porosity is due to the dehydration and re-crystallization of β-Ni(OH)_(2) nanoplates synthesized by a hydrothermal process.Thermogravimetric analysis shows that the decomposition temperature of the β-Ni(OH)_(2) nanostructures is related to their morphology.In electrochemical tests,the porous NiO nanostructures show stable cycling performance with retention of specific capacitance over 1000 cycles.Interestingly,the formation of nanocolumns by the stacking of β-Ni(OH)_(2) nanoslices/plates favors the creation of small pores in the NiO nanocrystals obtained after annealing,and the surface area is over five times larger than that of NiO nanoslices and nanoplates.Consequently,the specific capacitance of the porous NiO nanocolumns(390 F/g)is significantly higher than that of the nanoslices(176 F/g)or nanoplates(285 F/g)at a discharge current of 5 A/g.This approach provides a clear illustration of the process-structure-property relationship in nanocrystal synthesis and potentially offers strategies to enhance the performance of supercapacitor electrodes.
基金supported by the National Natural Science Foundation of China(61472005,61201252)CERNET Innovation Project(NGII20160207)
文摘Online fault detection is one of the key technologies to improve the performance of cloud systems. The current data of cloud systems is to be monitored, collected and used to reflect their state. Its use can potentially help cloud managers take some timely measures before fault occurrence in clouds. Because of the complex structure and dynamic change characteristics of the clouds, existing fault detection methods suffer from the problems of low efficiency and low accuracy. In order to solve them, this work proposes an online detection model based on asystematic parameter-search method called SVM-Grid, whose construction is based on a support vector machine(SVM). SVM-Grid is used to optimize parameters in SVM. Proper attributes of a cloud system's running data are selected by using Pearson correlation and principal component analysis for the model. Strategies of predicting cloud faults and updating fault sample databases are proposed to optimize the model and improve its performance.In comparison with some representative existing methods, the proposed model can achieve more efficient and accurate fault detection for cloud systems.
基金the National Natural Science Foundation of China(61971235,61871412,and 61771258)the Six Talented Eminence Foundation of Jiangsu Province(XYDXXJS-044)+4 种基金the China Postdoctoral Science Foundation(2018M630590)the 333 High-level Talents Training Project of Jiangsu Province,the 1311 Talents Plan of Nanjing University of Posts and Telecommunications(NUPT)the Open Research Fund of Jiangsu Engineering Research Center of Communication and Network Technology,NUPT(JSGCZX17011)the Scientific Research Foundation of NUPT(NY218058)the Open Research Fund of Anhui Provincial Key Laboratory of Network and Information Security(AHNIS2020001).
文摘As a future energy system,the smart grid is designed to improve the efficiency of traditional power systems while providing more stable and reliable services.However,this efficient and reliable service relies on collecting and analyzing users’electricity consumption data frequently,which induces various security and privacy threats.To address these challenges,we propose a double-blockchain assisted secure and anonymous data aggregation scheme for fog-enabled smart grid named DA-SADA.Specifically,we design a three-tier architecture-based data aggregation framework by integrating fog computing and the blockchain,which provides strong support for achieving efficient and secure data collection in smart grids.Subsequently,we develop a secure and anonymous data aggregation mechanism with low computational overhead by jointly leveraging the Paillier encryption,batch aggregation signature and anonymous authentication.In particular,the system achieves fine-grained data aggregation and provides effective support for power dispatching and price adjustment by the designed double-blockchain and two-level data aggregation.Finally,the superiority of the proposed scheme is illustrated by a series of security and computation cost analyses.
基金the National Natural Science Foundation of China(Nos.21804319,21971002)the Natural Science Foundation of Anhui province(Nos.1908085QB45 and 2008085QB81)the Education Departm ent of Anhui Province Foundation(No.KJ2019A0503).We thank the BL14W1 station in Shanghai Synchrotron Radiation Facility(SSRF)and 1W1B station for XAFS measurement in Beijing Synchrotron Radiation Facility(BSRF).The calculations in this paper have been done on the supercomputing system of the National Supercomputing Center in Changsha.
文摘The demand for high-performance non-precious-metal electrocatalysts to replace the noble metal-based catalysts for oxygen reduction reaction(ORR)is intensively increasing.Herein,single-atomic copper sites supported on N-doped three-dimensional hierarchically porous carbon catalyst(Cu_(1)/NC)was prepared by coordination pyrolysis strategy.Remarkably,the Cu_(1)/NC-900 catalyst not only exhibits excellent ORR performance with a half-wave potential of 0.894 V(vs.RHE)in alkaline media,outperforming those of commercial Pt/C(0.851 V)and Cu nanoparticles anchored on N-doped porous carbon(CuNPs/NC-900),but also demonstrates high stability and methanol tolerance.Moreover,the Cu_(1)/NC-900 based Zn-air battery exhibits higher power density,rechargeability and cyclic stability than the one based on Pt/C.Both experimental and theoretical investigations demonstrated that the excellent performance of the as-obtained Cu_(1)/NC-900 could be attributed to the synergistic effect between copper coordinated by three N atoms active sites and the neighbouring carbon defect,resulting in elevated Cu d-band centers of Cu atoms and facilitating intermediate desorption for ORR process.This study may lead towards the development of highly efficient non-noble metal catalysts for applications in electrochemical energy conversion.
基金financially supported by the National Natural Science Foundation of China(No.U2004177)Outstanding Youth Fund of Henan Province(No.212300410081)Natural Science Research Project of Henan Educational Committee(No.20A43001).
文摘In order to prevent the microwave leakage and mutual interference,more and more microwave absorbing devices are added into the design of electronic products to ensure its routine operation.In this work,we have successfully prepared MoS_(2)/TiO_(2)/Ti_(3)C_(2)T_(x) hierarchical composites by one-pot hydrothermal method and focused on the relationship between structures and electromagnetic absorbing properties.Supported by comprehensive characterizations,M0S_(2) nanosheets were proved to be anchored on the surface and interlayer of Ti_(3)C_(2)T_(x) through a hydrothermal process.Additionally,TiO_(2) nanoparticles were obtained in situ.Due to these hierarchical structures,the MoS_(2)/TiO_(2)/Ti_(3)C_(2)T_(x) composites showed greatly enhanced microwave absorbing performance.The MoS_(2)/TiO_(2)/Ti_(3)C_(2)T_(x) composites exhibit a maximum reflection loss value of -33.5 dB at 10.24 GHz and the effective absorption bandwidth covers 3.1GHz(13.9-17 GHz)at the thickness of 1.0 mm,implying the features of wide frequency and light weight.This work in the hierarchical structure of MoS_(2)/TiO_(2)/Ti_(3)C_(2)T_(x) composites opens a promising door to the exploration of constructing extraordinary electromagnetic wave absorbents.
基金Project supported by the National Natural Science Foundation of China(No.12171124)the Natural Science Foundation of Heilongjiang Province of China(No.ZD2022F003)+1 种基金the National High-end Foreign Experts Recruitment Plan of China(No.G2023012004L)the Alexander von Humboldt Foundation of Germany。
文摘This paper investigates the problem of outlier-resistant distributed fusion filtering(DFF)for a class of multi-sensor nonlinear singular systems(MSNSSs)under a dynamic event-triggered scheme(DETS).To relieve the effect of measurement outliers in data transmission,a self-adaptive saturation function is used.Moreover,to further reduce the energy consumption of each sensor node and improve the efficiency of resource utilization,a DETS is adopted to regulate the frequency of data transmission.For the addressed MSNSSs,our purpose is to construct the local outlier-resistant filter under the effects of the measurement outliers and the DETS;the local upper bound(UB)on the filtering error covariance(FEC)is derived by solving the difference equations and minimized by designing proper filter gains.Furthermore,according to the local filters and their UBs,a DFF algorithm is presented in terms of the inverse covariance intersection fusion rule.As such,the proposed DFF algorithm has the advantages of reducing the frequency of data transmission and the impact of measurement outliers,thereby improving the estimation performance.Moreover,the uniform boundedness of the filtering error is discussed and a corresponding sufficient condition is presented.Finally,the validity of the developed algorithm is checked using a simulation example.
基金the National Natured Science Foundation (No.10371006)the Natural Science Foundation of Anhui Province of China (2005 kj031ZI):050460103)
文摘Thc main aim of this paper is to use the continuation theorem of coincidence degree theory for studying the existence of periodic solutions to a kind of neutral functional differential equation as follows：（x（t）-^n∑i=1cix（t-ri））″=f（x（t））x′＋g（x（t-τ））＋p（t）.In order to do so, we analyze the structure of the linear difference operator A ： C2π→C2π, [Ax]（t） =x（t）-∑^ni=1cix（t-ri）to determine some flmdamental properties first, which we are going to use throughout this paper. Meanwhile, we also prove some new inequalities which are useful for estimating a priori bounds of periodie solutions.
基金the National Natural Science Foundations of China(Grant Nos.51972118,51961145101,51722202 and 11974022)the Guangzhou Science&Technology Project(202007020005)+1 种基金the Fundamental Research Funds for the Central Universities(D2190980)the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(2017BT01X137).
文摘Rapid development of solid-state lighting technology requires new materials with highly efficient and stable luminescence,and especially relies on blue light pumped red phosphors for improved light quality.Herein,we discovered an unprecedented red-emitting Mg_(2)AI_(4)Si_(5)0_(18):Eu^(2+)composite phosphor(λex=450 nm,λem=620 nm)via the crystallization of MgO-AI_(2)O_(3)-Sio_(2) aluminosilicate glass.Combined experimental measurement and first-principles calculations verify that Eu^(2+)dopants insert at the vacant channel of Mg_(2)AI_(4)Si_(5)0_(18)crystal with six-fold coordination responsible for the peculiar red emission.Importantly,the resulting phosphor exhibits high internal/external quantum efficiency of 94.5/70.6%,and stable emission against thermal quenching,which reaches industry production.The maximum luminous flux and luminous efficiency of the constructed laser driven red emitting device reaches as high as 274 Im and 54lm W^(-1),respectively.The combinations of extraordinary optical properties coupled with economically favorable and innovative preparation method indicate,that the Mg_(2)AI_(4)Si_(5)0_(18):Eu^(2+)composite phosphor will provide a significant step towards the development of high-power solid-state lighting.
基金supported in part by the National Natural Science Foundation of China(62103004,62273088,62273005,62003121)Anhui Provincial Natural Science Foundation of China(2108085QA13)+4 种基金the Natural Science Foundation of Zhejiang Province(LY24F030006)the Science and Technology Plan of Wuhu City(2022jc24)Anhui Polytechnic University Youth Top-Notch Talent Support Program(2018BJRC009)Anhui Polytechnic University High-End Equipment Intelligent Control Innovation Team(2021CXTD005)Anhui Future Technology Research Institute Foundation(2023qyhz08,2023qyhz09)。
文摘In this paper,the recursive filtering problem is considered for stochastic systems over filter-and-forward successive relay(FFSR)networks.An FFSR is located between the sensor and the remote filter to forward the measurement.In the successive relay,two cooperative relay nodes are adopted to forward the signals alternatively,thereby existing switching characteristics and inter-relay interferences(IRI).Since the filter-and-forward scheme is employed,the signal received by the relay is retransmitted after it passes through a linear filter.The objective of the paper is to concurrently design optimal recursive filters for FFSR and stochastic systems against switching characteristics and IRI of relays.First,a uniform measurement model is proposed by analyzing the transmission mechanism of FFSR.Then,novel filter structures with switching parameters are constructed for both FFSR and stochastic systems.With the help of the inductive method,filtering error covariances are presented in the form of coupled difference equations.Next,the desired filter gain matrices are further obtained by minimizing the trace of filtering error covariances.Moreover,the stability performance of the filtering algorithm is analyzed where the uniform bound is guaranteed on the filtering error covariance.Finally,the effectiveness of the proposed filtering method over FFSR is verified by a three-order resistance-inductance-capacitance circuit system.
基金financially supported by the National Natural Science Foundation of China(No.51704001)the Natural Science Foundation of Anhui Province,China(No.2008085J23)the Talent Project of Anhui Province,China(Z175050020001)。
文摘The effects of laser parameters and interlayer material on the microstructure and properties of the welded joint between 6061 aluminum alloy and stainless steel were studied.The results show that the density and microstructure of the welded joint can be optimized by changing the laser power with 0.05 mm Cu foil and 0.1 mm Ni foil as interlayer.A large number of new Cu-Al binary phases were found near the aluminum alloy,which effectively inhibited the formation of the binary brittle phase of Fe-Al.The maximum shear force of 1350.96 N was obtained with laser power of 2200 W.The shear force of the welded joint increased to 1754.73 N when the thickness of the Cu foil thickness changed to 0.02 mm.
基金Project supported by the National Natural Science Foundation of China(52072348 and 52104272)Scientific Research Start-up Fund of Anhui Polytechnic University(2020YQQ053)+1 种基金Scientific Research Project of Anhui Polytechnic University(Xjky2020083)Innovation and Entrepreneurship Education and Training Project for Anhui Provincial College Students(S202110363258)。
文摘Rare earth co-doped phosphor for fluorescence intensity ratio(FIR) thermometer has gained increasing attention in recent years. Herein, the novel Tb^(3+)and Eu^(3+)co-doped K_(3)SrBi(P_(2)O_(7))_(2)(KSBP) phosphate phosphors were reported. The crystal structure of the title phosphor was determined using Rietveld refinement and proved to have a three-dimensional structure. The time-resolved spectroscopy reveals that there is almost no energy transfer between Tb^(3+)and Eu^(3+). More importantly, Tb^(3+)and Eu^(3+)emissions show different thermal quenching behaviors, which claims the potential of this material for application in optical thermometer. The FIR of the typical KSBP:0.02Tb^(3+),0.04Eu^(3+)sample demonstrates a polynomial relationship as a function of temperature and the absolute and relative sensitivity are0.025 K^(-1) and 0.59%/K, respectively. In general, our study reports a novel and potential KSBP:Tb^(3+),Eu^(3+)phosphate phosphor that is promising for use in high-sensitive FIR thermometers.
基金financially suppor ted by Key Research and Development Project of Anhui Province(No.2023h11020002)Natural Science Research Project for Universities in Anhui Province(No.KJ2021ZD0006)+3 种基金Natural Science Foundation of Anhui Province(No.2208085MB21)Fundamental Research Funds for the Central Universities of China(No.PA2022GDSK0056)Anhui Laboratory of Molecule-Based Materials(No.fzj22009)National Natural Science Foundation of China(Nos.21725102,22205108)。
文摘Over the past few decades,photocatalysis technology has received extensive attention because of its potential to mitigate or solve energy and environmental pollution problems.Designing novel materials with outstanding photocatalytic activities has become a research hotspot in this field.In this study,we prepared a series of photocatalysts in which BiOCl nanosheets were modified with carbon quantum dots(CQDs)to form CQDs/BiOCl composites by using a simple solvothermal method.The photocatalytic performance of the resulting CQDs/BiOCl composite photocatalysts was assessed by rhodamine B and tetracycline degradation under visible-light irradiation.Compared with bare BiOCl,the photocatalytic activity of the CQDs/BiOCl composites was significantly enhanced,and the 5 wt%CQDs/BiOCl composite exhibited the highest photocatalytic activity with a degradation efficiency of 94.5%after 30 min of irradiation.Moreover,photocatalytic N_(2)reduction performance was significantly improved after introducing CQDs.The 5 wt%CQDs/BiOCl composite displayed the highest photocatalytic N_(2)reduction performance to yield NH_3(346.25μmol/(g h)),which is significantly higher than those of 3 wt%CQDs/BiOCl(256.04μmol/(g h)),7 wt%CQDs/BiOCl(254.07μmol/(g h)),and bare BiOCl(240.19μmol/(g h)).Our systematic characterizations revealed that the key role of CQDs in improving photocatalytic performance is due to their increased light harvesting capacity,remarkable electron transfer ability,and higher photocatalytic activity sites.
基金Supported by the Project of China Geological Survey on Ministry of Natural Resources(DD20190647)the Project of Collaborative Innovation Among Universities in Anhui Province(21KZZ701)Anhui University Natural Science Research Major Project(KJ2020ZD73)。
文摘To explore the law of energy evolution and the change of damage before and after specimen failure,the conventional triaxial compression tests(5,10,15,20,and 30 MPa)of basalt fiber reinforced concrete(BFRC)with different fiber volume fractions(0,0.2%and 0.4%)were carried out by MTS816 rock testing system,and the cyclic loading and unloading tests of BFRC with a fiber content of 0.2%were carried out.The experimental results show that the peak strength and strain of BFRC increase with the increase of confining pressure.Tensile failure occurs under low confining pressure,and shear failure occurs under high confining pressure.The best volume fraction of fiber is 0.2%.Under different confining pressures,the input energy,elastic energy,plastic properties,and dissipated energy of the samples first increase and then decrease to a stable level.The elastic energy and dissipated energy reach the maximum near the peak stress,while the input energy and plastic properties reach the maximum at the peak.At the same time,the damage increases continuously with the input of load under different confining pressures,indicating that the failure of the specimen is a process of energy accumulation.
基金supported by the National Natural Science Foundation of China(Nos.21901007 and 21866032)we acknowledge the BL12B beamline of National Synchrotron Radiation Laboratory(NSRL)in Hefei and 1W1B station of Beijing Synchrotron Radiation Facility(BSRF).Our work is completed on the“Explorer 100”cluster system of Tsinghua HPC Platform.
文摘Atomic non-noble metal materials show the potential to substitute noble metals in catalysis.Herein,melamine formaldehyde resin is developed to synthesize atomic iron on mesoporous nitrogen-doped carbon.The triazine units with abundant nitrogen content and cavity can realize effectively anchoring of single metal atoms.The atomic iron with unique charge and coordination characteristics shows superior catalytic performance in dehydrogenation reaction.Various N-heterocycles compounds and amines can be efficiently dehydrogenated into the corresponding products at room temperature,which is the mildest of all reported reaction conditions even when noble metal catalysts are considered.Therefore,development of atomic non-noble metal catalysts with mesoporous structure may provide an effective way to realize the substitution for noble metals in heterogeneous catalysis.
基金supported by financial support in part by NSFC (91961106, 51902253, 21725102)Anhui Provincial Natural Science Foundation (Grant 2108085MB46)+1 种基金Key Project of Youth Elite Support Plan in Universities of Anhui Province (Grant gxyqZD2021121)Shaanxi Provincial Natural Science Foundation (2020JQ-778)。
文摘Very recently, the local coordination environment of active sites has been found to strongly influence their performance in electrocatalytic CO_(2) reduction by tuning the intrinsic kinetics of CO_(2) activation and intermediate stabilization. It is imperative to elucidate the mechanism for such an influence towards the rational design of efficient catalysts;however, the complex interactions between the multiple factors involved in the system make it challenging to establish a clear structure–performance relationship. In this work, we chose ion-intercalated silver(I)-based coordination networks(AgCNs) with a well-defined structure as a model platform, which enables us to understand the regulation mechanism of counterions as the counterions are the only tuning factor involved in such a system. We prepared two isostructural Ag CNs with different intercalation ions or counterions of BF_(4)^(-) and ClO_(4)^(-)(named as AgCNs-BF_(4) and AgCNs-ClO_(4)) and found that the former has a more competitive CO_(2) electroreduction performance than the latter. AgCNs-BF_(4) achieves the highest Faradaic efficiency for CO_(2) to CO of 87.1% at-1.0 V(vs. RHE) with a higher partial current density, while AgCNs-ClO_(4) exhibits only 77.2% at the same applied potential.Spectroscopic characterizations and theoretical calculation reveal that the presence of BF_(4)^(-)is more favorable for stabilizing the COOH^(*) intermediate by weakening hydrogen bonds, which accounts for the superior activity of Ag CNs-BF_(4).
基金supported by the National Natural Science Foundation of China(Nos.51902003,22002085,21771003,21501004)the University Synergy Innovation Program of Anhui Province(No.GXXT-2021-020)+4 种基金the Anhui Province Natural Science Foundation(Nos.2108085QB71 and 2008085QB53)the Natural Science Research Project of Anhui Province Education Department(No.KJ2019A0581)the Open Project of Key Laboratory of Metallurgical Emission Reduction&Resources Recycling of Ministry of Education(No.JKF21-03)the Open Foundation of Anhui Laboratory of Clean Catalytic Engineering(No.LCCE-01)the Open Research Funds of Jiangxi Province Engineering Research Center of Ecological Chemical Industry(STKF2109).
文摘Dual-active sites(DASs)catalysts have positive potential applications in broad fields because of their specific active sites and synergistic catalytic effects.Therefore,the controllable synthesis and finely regulating the activity of such catalysts has become a hot research area for now.In this work,we developed a pyrolysis-etching-hydrogen activation strategy to prepare the DASs catalysts involving single-atom Cu and B on N-doped porous carbon material(Cu_(1)-B/NPC).Numerous systematic characterization and density functional theoretical(DFT)calculation results showed that the Cu and B existed as Cu-N4 porphyrinlike unit and B-N_(3)unit in the obtained catalyst.DFT calculations further revealed that single-atom Cu and B sites were linked by bridging N atoms to form the Cu_(1)-B-N6 dual-sites.The Cu_(1)-B/NPC catalyst was more effective than the single-active site catalysts with B-N_(3)sites in NPC(B/NPC)and Cu-N4 porphyrin-like sites in NPC(Cu_(1)/NPC),respectively,for the dehydrogenative coupling of dimethylphenylsilane(DiMPSH)with various alcohols,performing the great activity(>99%)and selectivity(>99%).The catalytic performances of the Cu_(1)-B/NPC catalyst remained nearly unchanged after five cycles,also indicating its outstanding recyclability.DFT calculations showed that the Cu_(1)-B-N6 dual-sites exhibited the lowest energy profile on the potential energy surface than that of sole B-N_(3)and Cu-N4 porphyrin-like sites.Furthermore,the rate-limiting step of dehydrogenation of DiMPSH on Cu_(1)-B-N6 dual-sites also showed a much lower activation energy than the other two single sites.Benefitting from the superiority of the Cu_(1)-B-N6 dual-sites,the Cu_(1)-B/NPC catalyst can also be used for CO_(2)electroreduction to produce syngas.Thus,DASs catalysts are promising to achieve multifunctional catalytic properties and have aroused positive attention in the field of catalysis.
基金This work was supported by Fundamental Research Funds for Central Universities(No.GK202201003)Funded Projects for the Academic Leaders and Academic Backbones of Shaanxi Normal University(No.18QNGG008)Shaanxi Sanqin Scholars Innovation Team,and Free Exploring Research Project for PhD Students of Shaanxi Normal University(No.2020TS106).
文摘Plasmon-generated hot electrons show great potential for driving chemical reactions.The utilization efficiency of hot electrons is highly dependent on the interaction of the electronic states at the interfaces between plasmonic nanoparticles and other materials/molecules.Strong interaction can produce new hybridized electron states,which permit direct hot-electron transfer,a more efficient transfer mechanism.However,Au usually has very weak interaction with most molecules because of its inertness,which makes direct hot-electron transfer impossible.Herein,the improvement of the hot-electron transfer efficiency from Au to N_(2)is demonstrated by introducing a Ru bridging layer.Both the N_(2)fixation rate and Faradic efficiency(FE)are enhanced by the excitation of plasmons.The enhancement of the N_(2)fixation rate is found to arise from plasmon-generated hot electrons.Theoretical calculations show that the strong interaction of the Ru electronic states with the N_(2)molecular orbitals produces new hybridized electronic states,and the Ru d electrons also strongly couple with the Au sp electrons.Such a bridging role of Ru makes direct hot-electron transfer from Au to N_(2)possible,improving the FE of nitrogen fixation.Our findings demonstrate a new approach to increasing the utilization efficiency of plasmonic hot electrons for chemical reactions and will be helpful to the design of plasmonic catalysts in the future.
基金This work was financially supported by the National Natural Science Foundation of China(No.31800144 and No.32030108)the Natural Science Foundation of Shanghai(No.18ZR1448700)the Agricultural Science and Technology Innovation Program(ASTIP)of the Chinese Academy of Agricultural Science.
文摘Variations in the pathogenicity of Newcastle disease virus(NDV),the agent causing Newcastle disease,are associated with variants of different virulence.A few studies have characterized the expression of microRNAs(miRNAs)in NDV-infected avian cells.Here,the expression of miRNAs in chicken embryo fibroblasts(CEFs)infected with Herts/33 and LaSota NDV strains(highly virulent and nonvirulent,respectively)was determined using RNA sequencing.miRNAs involved in NDV infection included 562 previously documented and 184 novel miRNAs.miRNA target genes involved transcription factors,cell apoptosis,ubiquitin-mediated proteolysis,and protein processing in the endoplasmic reticulum.Potential target genes associated with autophagy were verified by qRT-PCR.No studies have documented the miRNA profles of CEFs infected with NDVs variants.This study adds to our knowledge of the cellular miRNAs involved in NDV infection and the complex molecular mechanisms mediating virus-host interactions.The results of this study will aid the development of strategies against the chicken virus.
基金This work was supported by the National Postdoctoral Program for Innovative Talents(No.BX20220159)the National Natural Science Foundation of China(No.21890383)。
文摘It is significant to optimize geometric configuration of metal catalytic sites and boost their catalytic activity.Herein,we synthesized isolated single Zn-N_(4)sites on N-doped carbon(Zn-CN)by pyrolyzing zeolite imidazole framework-8(ZIF-8)at different temperatures.For the reciprocal transformation between benzyl alcohol and benzaldehyde,the catalytic activities of Zn-CN catalysts exhibited a volcano-like trend as the pyrolysis temperatures increased.The optimal catalyst was Zn-CN-900,with outstanding catalytic activity exceeding commercial 20 wt.%Pd/C and 20 wt.%Pt/C,promising to substitute the noble metalbased catalysts.X-ray absorption near-edge structure(XANES)measurements and density functional theory(DFT)calculation revealed the gradual transformation from tetrahedral ZnN_(4)sites of ZIF-8 into planar ZnN_(4)sites above 700℃,with the maximum planar ZnN_(4)sites in Zn-CN-900.The stronger adsorption between reactants and planar ZnN_(4)sites facilitated the activation of reactants compared with tetrahedral ZnN_(4)sites.This work will provide valuable insight into rational design of efficient catalysts by optimizing geometric configuration of catalytic sites.
基金co-supported by the National Natural Science Foundation of China(No.51875134)the Self-Planned Task of State Key Laboratory of Robotics and System(HIT),China(No.SKLRS202218B)the Production and Research Project of HIT Wuhu Robot Technology Research Institute,China(No.HIT-CXY-CMP1-MWLRP-21-01).
文摘In comparison to the traditional fixed-angle trajectory,the variable-angle trajectory has a greater design space.However,it is a challenge to determine which common design curve structure is the most effective for improving mechanical performance.This work explores the effects of various design curves such as fixed-angle curve,linear curve,arc curve,sine curve,Bezier curve,and cubic polynomial curve trajectories on mechanical performance of laminates,including vibration modal performance and buckling performance.Genetic algorithm and improved NSGA-II algorithm are then used to optimize various curve structures.The results are confirmed utilizing thermoplastic Carbon Fiber(CF)/Polyether-Ether-Ketone(PEEK)laminates made by robotic fiber placement experiments.The relationship model between different mechanical performance and curve design variables is established.The optimization of variable-angle structure with mechanical properties as input variables is achieved.Meanwhile,a full-process angle-variable laying software platform from trajectory planning(CAD),trajectory optimization to manufacturing(CAM)is developed for facilitating the fiber placement application.
