The lifespan models of commercial 18650-type lithium ion batteries （nominal capacity of 1150 mA-h） were presented. The lifespan was extrapolated based on this model. The results indicate that the relationship of cap...The lifespan models of commercial 18650-type lithium ion batteries （nominal capacity of 1150 mA-h） were presented. The lifespan was extrapolated based on this model. The results indicate that the relationship of capacity retention and cycle number can be expressed by Gaussian function. The selecting function and optimal precision were verified through actual match detection and a range of alternating current impedance testing. The cycle life model with high precision （〉99%） is beneficial to shortening the orediction time and cutting the prediction cost.展开更多
The electrochemical migration（ECM） behavior and mechanism of immersion silver processing circuit board（PCB-ImAg）and hot air solder leveling circuit board（PCB-HASL） under the 0.1 mol/L Na2SO4 absorbed thin liquid...The electrochemical migration（ECM） behavior and mechanism of immersion silver processing circuit board（PCB-ImAg）and hot air solder leveling circuit board（PCB-HASL） under the 0.1 mol/L Na2SO4 absorbed thin liquid films with different thicknesses were investigated using stereo microscopy and scanning electron microscopy（SEM）.Meanwhile,the corrosion tendency and kinetics rule of metal plates after bias application were analyzed with the aid of electrochemical impedance spectroscopy（EIS）and scanning Kelvin probe（SKP）.Results showed that under different humidity conditions,the amount of migrating corrosion products of silver for PCB-ImAg was limited,while on PCB-HASL both copper dendrites and precipitates such as sulfate and metal oxides of copper/tin were found under a high humidity condition（exceeding 85%）.SKP results indicated that the cathode plate of two kinds of PCB materials had a higher corrosion tendency after bias application.An ECM model involving multi-metal reactions was proposed and the differences of ECM behaviors for two kinds of PCB materials were compared.展开更多
We study the quantum fluctuations of the charge and current of two L-C dissipative mesoscopic circuit with the mutual inductance in the vacuum state.Our results show that the system state will evolve to a squeezed coh...We study the quantum fluctuations of the charge and current of two L-C dissipative mesoscopic circuit with the mutual inductance in the vacuum state.Our results show that the system state will evolve to a squeezed coherent state under the effect of external source.We find that the squeezing amplitude parameter is relative to the parameters of circuit and the mutual-inductance coefficient in the existence of dissipation.When the circuit has no dissipation or there is complete coupling between two meshes,the squeezing amplitude parameter only depends on the capacitance's ratio.展开更多
The influence of implantation of N+ions of different energies on the nanostructure of7049Al substrates and the corrosioninhibition of produced Al samples in a3.5%NaCl solution was studied.The X-ray diffraction(XRD)res...The influence of implantation of N+ions of different energies on the nanostructure of7049Al substrates and the corrosioninhibition of produced Al samples in a3.5%NaCl solution was studied.The X-ray diffraction(XRD)results confirmed the formationof AlN as a result of N+ion implantation.The atomic force microscope(AFM)results showed that grains of larger scale are formedby increasing N+energy which can be due to heat accumulation in the sample during implantation causing higher rate of diffusion inthe sample,hence decreasing the number of defects.Corrosion resistance of the samples was studied by the electrochemicalimpedance spectroscopy(EIS)measurements.Results showed that corrosion resistance of implanted Al increases with increasing N+ion energy.The equivalent circuits for the N+implanted Al samples with different energies were obtained,using the EIS data whichshowed strong dependence of the equivalent circuit elements on the surface morphology of the samples.Finally,the relationshipbetween corrosion inhibition and equivalent circuit elements was investigated.展开更多
Option contract is one of the most important instruments for power generators developing bidding strategies and hedging market risk. Based on the peculiarities of bid-based-pool （BBP） power markets, a joint two-stag...Option contract is one of the most important instruments for power generators developing bidding strategies and hedging market risk. Based on the peculiarities of bid-based-pool （BBP） power markets, a joint two-stage Cournot equilibrium model for option and spot markets is developed, and analytical formulas for market equilibrium are derived using a backward induction method. The impacts of option contract on efficiency of electricity markets and the behaviors of strategic generators are analyzed. The results show that strategic generators will voluntarily participate in strategic option contracting, and the existence of option contract accelerates the degree of competitive intensity in electricity markets and mitigates the market power abuse of generators to a large extent. In order to retain high spot market price and stable revenues, generators are interested in holding extremely high volatility of spot market price.展开更多
A miniature thermoacoustic prime mover, consuming heat to radiate sound, may be considered as a potential way of heat management in microcircuits because of its simplicity and stability. A prototype with variable reso...A miniature thermoacoustic prime mover, consuming heat to radiate sound, may be considered as a potential way of heat management in microcircuits because of its simplicity and stability. A prototype with variable resonant tube length of 10 to 25 cm was built, and experiments were carried out to observe its performance, such as onset temperature, oscillation amplitude and operating frequency. The results with atmospheric air showed that proper structures and operating conditions can make the system start an oscillation at a temperature lower than 100 ℃, which proves the feasibility of potential usage in electronic units. The influences of stack position, heat input power or tube inclination on the oscillation amplitude, onset temperature and operating frequency are also presented.展开更多
Corrosion behaviour of the studied Ti12Mo and Ti60Ta alloys with the same Mo equivalent values （12%, mass fraction） together with the currently used metallic biomaterials Cp-Ti were investigated for dental applicati...Corrosion behaviour of the studied Ti12Mo and Ti60Ta alloys with the same Mo equivalent values （12%, mass fraction） together with the currently used metallic biomaterials Cp-Ti were investigated for dental applications. The electrochemical properties of the samples were examined using electrochemical techniques： such as open-circuit potential, potentiodynamic polarization curves and electrochemical impedance spectroscopy （EIS）, in two electrochemical media of artificial saliva and fluoridated artificial saliva （0.1%fluoride ions, F-） at 37 °C. Fluoride is commonly included in toothpastes, odontological gels and dental rinses to prevent dental caries and relieve dental sensitivity. The passive behaviour for all the titanium samples is observed for both solutions. The Ti60Ta alloy appears to possess superior corrosion resistance than the Ti12Mo and Cp-Ti in both electrochemical media.展开更多
On the basis of analysis on the temperature monitoring methods for high voltage devices, a new type of fiber optic sensor structure with reference channel is given. And the operation principle of fiber optic sensor is...On the basis of analysis on the temperature monitoring methods for high voltage devices, a new type of fiber optic sensor structure with reference channel is given. And the operation principle of fiber optic sensor is analysed at large based on the absorption of semiconductor chip. The mathematical model of both devices and the whole system are also given. It is proved by the experiment that this mathematical model is reliable.展开更多
Vanadium pentoxide xerogel films used for lithium rechargeable batteries were prepared from crystalline c-V2O5 by melt quenching method,then the electrochemical process of lithium intercalation into vanadium pentoxide...Vanadium pentoxide xerogel films used for lithium rechargeable batteries were prepared from crystalline c-V2O5 by melt quenching method,then the electrochemical process of lithium intercalation into vanadium pentoxide xerogel films was simulated with an equivalent circuit model, which was derived from the mechanism of electrode reactions. Measured electrochemical impedance spectra at various electrode potentials were analyzed by using the complex non-linear least-squares fitting method. The results show that impedance spectra consist of 2 high-to- medium frequency depressed arcs and a low frequency straight line. The high frequency arc is attributed to the absorption reaction of lithium ions into the oxide film, the medium frequency arc is attributed to the charge transfer reaction at the vanadium oxide/electrolyte interface and the low frequency is characterized by a straight line with a phase angle of 45° corresponding to the diffusion of lithium ion through vanadium oxide phase. The experimental and calculated results are compared and discussed focusing on the electrochemical performance and the state of charge of the electrode. Moreover, the high consistence of the fitted values of the model to the experimental data indicates that this mathematical model does give a satisfying description of the intercalation process of vanadium pentoxide xerogel films.展开更多
基金Projects(51204209,51274240)supported by the National Natural Science Foundation of ChinaProject(HNDLKJ[2012]001-1)supported by Henan Electric Power Science&Technology Supporting Program,China
文摘The lifespan models of commercial 18650-type lithium ion batteries （nominal capacity of 1150 mA-h） were presented. The lifespan was extrapolated based on this model. The results indicate that the relationship of capacity retention and cycle number can be expressed by Gaussian function. The selecting function and optimal precision were verified through actual match detection and a range of alternating current impedance testing. The cycle life model with high precision （〉99%） is beneficial to shortening the orediction time and cutting the prediction cost.
基金Project(51271032)supported by the National Natural Science Foundation of China
文摘The electrochemical migration（ECM） behavior and mechanism of immersion silver processing circuit board（PCB-ImAg）and hot air solder leveling circuit board（PCB-HASL） under the 0.1 mol/L Na2SO4 absorbed thin liquid films with different thicknesses were investigated using stereo microscopy and scanning electron microscopy（SEM）.Meanwhile,the corrosion tendency and kinetics rule of metal plates after bias application were analyzed with the aid of electrochemical impedance spectroscopy（EIS）and scanning Kelvin probe（SKP）.Results showed that under different humidity conditions,the amount of migrating corrosion products of silver for PCB-ImAg was limited,while on PCB-HASL both copper dendrites and precipitates such as sulfate and metal oxides of copper/tin were found under a high humidity condition（exceeding 85%）.SKP results indicated that the cathode plate of two kinds of PCB materials had a higher corrosion tendency after bias application.An ECM model involving multi-metal reactions was proposed and the differences of ECM behaviors for two kinds of PCB materials were compared.
文摘We study the quantum fluctuations of the charge and current of two L-C dissipative mesoscopic circuit with the mutual inductance in the vacuum state.Our results show that the system state will evolve to a squeezed coherent state under the effect of external source.We find that the squeezing amplitude parameter is relative to the parameters of circuit and the mutual-inductance coefficient in the existence of dissipation.When the circuit has no dissipation or there is complete coupling between two meshes,the squeezing amplitude parameter only depends on the capacitance's ratio.
基金University of Tehran and the Iran National Science Foundation(INSF)center of excellence for structural and microscopic properties of matter,Department of Physics,University of Tehran for partial support of this work
文摘The influence of implantation of N+ions of different energies on the nanostructure of7049Al substrates and the corrosioninhibition of produced Al samples in a3.5%NaCl solution was studied.The X-ray diffraction(XRD)results confirmed the formationof AlN as a result of N+ion implantation.The atomic force microscope(AFM)results showed that grains of larger scale are formedby increasing N+energy which can be due to heat accumulation in the sample during implantation causing higher rate of diffusion inthe sample,hence decreasing the number of defects.Corrosion resistance of the samples was studied by the electrochemicalimpedance spectroscopy(EIS)measurements.Results showed that corrosion resistance of implanted Al increases with increasing N+ion energy.The equivalent circuits for the N+implanted Al samples with different energies were obtained,using the EIS data whichshowed strong dependence of the equivalent circuit elements on the surface morphology of the samples.Finally,the relationshipbetween corrosion inhibition and equivalent circuit elements was investigated.
基金supported by the National Natural Science Foundation of China (Grant No.70871074)
文摘Option contract is one of the most important instruments for power generators developing bidding strategies and hedging market risk. Based on the peculiarities of bid-based-pool （BBP） power markets, a joint two-stage Cournot equilibrium model for option and spot markets is developed, and analytical formulas for market equilibrium are derived using a backward induction method. The impacts of option contract on efficiency of electricity markets and the behaviors of strategic generators are analyzed. The results show that strategic generators will voluntarily participate in strategic option contracting, and the existence of option contract accelerates the degree of competitive intensity in electricity markets and mitigates the market power abuse of generators to a large extent. In order to retain high spot market price and stable revenues, generators are interested in holding extremely high volatility of spot market price.
基金Project supported by the National Natural Sciences Foundation of China (No. 50536040), the China Postdoctoral Science Foundation(No. 2005038280), and the Natural Sciences Foundation of ZhejiangProvince (No. Y104326), China
文摘A miniature thermoacoustic prime mover, consuming heat to radiate sound, may be considered as a potential way of heat management in microcircuits because of its simplicity and stability. A prototype with variable resonant tube length of 10 to 25 cm was built, and experiments were carried out to observe its performance, such as onset temperature, oscillation amplitude and operating frequency. The results with atmospheric air showed that proper structures and operating conditions can make the system start an oscillation at a temperature lower than 100 ℃, which proves the feasibility of potential usage in electronic units. The influences of stack position, heat input power or tube inclination on the oscillation amplitude, onset temperature and operating frequency are also presented.
基金Project (PN-II-ID-PCE-2011-3-0218) supported by the Romanian National Authority for Scientific Research,CNCS-UEFISCDI
文摘Corrosion behaviour of the studied Ti12Mo and Ti60Ta alloys with the same Mo equivalent values （12%, mass fraction） together with the currently used metallic biomaterials Cp-Ti were investigated for dental applications. The electrochemical properties of the samples were examined using electrochemical techniques： such as open-circuit potential, potentiodynamic polarization curves and electrochemical impedance spectroscopy （EIS）, in two electrochemical media of artificial saliva and fluoridated artificial saliva （0.1%fluoride ions, F-） at 37 °C. Fluoride is commonly included in toothpastes, odontological gels and dental rinses to prevent dental caries and relieve dental sensitivity. The passive behaviour for all the titanium samples is observed for both solutions. The Ti60Ta alloy appears to possess superior corrosion resistance than the Ti12Mo and Cp-Ti in both electrochemical media.
文摘On the basis of analysis on the temperature monitoring methods for high voltage devices, a new type of fiber optic sensor structure with reference channel is given. And the operation principle of fiber optic sensor is analysed at large based on the absorption of semiconductor chip. The mathematical model of both devices and the whole system are also given. It is proved by the experiment that this mathematical model is reliable.
文摘Vanadium pentoxide xerogel films used for lithium rechargeable batteries were prepared from crystalline c-V2O5 by melt quenching method,then the electrochemical process of lithium intercalation into vanadium pentoxide xerogel films was simulated with an equivalent circuit model, which was derived from the mechanism of electrode reactions. Measured electrochemical impedance spectra at various electrode potentials were analyzed by using the complex non-linear least-squares fitting method. The results show that impedance spectra consist of 2 high-to- medium frequency depressed arcs and a low frequency straight line. The high frequency arc is attributed to the absorption reaction of lithium ions into the oxide film, the medium frequency arc is attributed to the charge transfer reaction at the vanadium oxide/electrolyte interface and the low frequency is characterized by a straight line with a phase angle of 45° corresponding to the diffusion of lithium ion through vanadium oxide phase. The experimental and calculated results are compared and discussed focusing on the electrochemical performance and the state of charge of the electrode. Moreover, the high consistence of the fitted values of the model to the experimental data indicates that this mathematical model does give a satisfying description of the intercalation process of vanadium pentoxide xerogel films.
