This study focuses on the characteristics of the 30 60-day oscillation (MJO) associated with the interannual variability of the thermal state in the western Pacific warm pool. The composite results show that, the ampl...This study focuses on the characteristics of the 30 60-day oscillation (MJO) associated with the interannual variability of the thermal state in the western Pacific warm pool. The composite results show that, the amplitude of MJO convection over the tropical western Pacific tends to intensify (reduce) in the WARM (COLD) case. The negative correlations between MJO convection in the WARM and in the COLD cases are examined to be significant over most of the Asian-Pacific region. The evolutions of MJO convection and lower circulation, on the one hand, exhibit larger differences between the WARM and COLD cases, but on the other hand, display a unique feature in that a well-developed MJO cyclone (anticyclone) is anchored over the Asian-Western Pacific domain at the peak enhanced (suppressed) MJO convection phase over the western Pacific warm pool, either in the WARM or in the COLD case. This unique feature of MJO shows a Gill-type response of lower circulation to the convection and is inferred to be an inherent appearance of MJO. The context in the paper suggests there may exist interactions between MJO and the interannual variability of the thermal state in the western Pacific warm pool.展开更多
We study a system consisting of two identical non-interacting single-mode cavity fields coupled to a common vacuum environment and provide general, explicit, and exact solutions to its master equation by means of the ...We study a system consisting of two identical non-interacting single-mode cavity fields coupled to a common vacuum environment and provide general, explicit, and exact solutions to its master equation by means of the characteristic function method. We analyze the entanglement dynamics of two-mode squeezed thermal state in this model and show that its entanglement dynamics is strongly determined by the two-mode squeezing parameter and the purity. In particular, we find that two-mode squeezed thermal state with the squeezing parameter r ≤ -(1/2) In √u is extremely fragile and almost does not survive in a common vacuum environment. We investigate the time evolution of nonlocality for two-mode squeezed thermal state in such an environment. It is found that the evolved state loses its nonlocality in the beginning of the evolution, but after a time, the revival of nonlocality can occur.展开更多
We investigate how displaced thermal states (DTSs) evolve in a laser channel. Remarkably, the initial DTS, an example of a mixed state, still remains mixed and thermal. At long times, they finally decay to a highly ...We investigate how displaced thermal states (DTSs) evolve in a laser channel. Remarkably, the initial DTS, an example of a mixed state, still remains mixed and thermal. At long times, they finally decay to a highly classical thermal field only related to the laser parameters κ and g. The normal ordering product of density operator of the DTS in the laser channel leads to obtaining the analytical time-evolution expressions of the photon number, Wigner function, and von Neumann entropy. Also, some interesting results are presented via numerically investigating these explicit time-dependent expressions.展开更多
In the coherent thermal state representation we introduce thermal Wigner operator and find that it is'squeezed' under the thermal transformation. The thermal Wigner operator provides us with a new direct and n...In the coherent thermal state representation we introduce thermal Wigner operator and find that it is'squeezed' under the thermal transformation. The thermal Wigner operator provides us with a new direct and neatapproach for deriving Wigner functions of thermal states.展开更多
By using the technique of integration within an ordered product of operators, the normal ordered density operator of the photon-subtracted squeezed thermal state (PSSTS) is derived. Then the corresponding Wigner fun...By using the technique of integration within an ordered product of operators, the normal ordered density operator of the photon-subtracted squeezed thermal state (PSSTS) is derived. Then the corresponding Wigner function is presented by using the coherent state representation of the Wigner operator. The nonclassical properties of the PSSTS are discussed based on the negativity of the Wigner function.展开更多
For the first time,we derive the compact forms of normalization factors for photon-added(-subtracted) two-mode squeezed thermal states by using the P-representation and the integration within an ordered product of o...For the first time,we derive the compact forms of normalization factors for photon-added(-subtracted) two-mode squeezed thermal states by using the P-representation and the integration within an ordered product of operators(IWOP) technique.It is found that these two factors are related to the Jacobi polynomials.In addition,some new relationships for Jacobi polynomials are presented.展开更多
We employ the coherent thermal states(a kind of entangled states)in thermal field dynamics to establisha complete entangled state formalism expressing pseudo-classical representations of density operator for light fie...We employ the coherent thermal states(a kind of entangled states)in thermal field dynamics to establisha complete entangled state formalism expressing pseudo-classical representations of density operator for light field.Especially,the relationship between the coherent thermal state and the characteristic function and the positive Prepresentation in quantum optics theory are obtained.展开更多
Based on the Wigner-function method, we investigate the parity detection and phase sensitivity in a Mach–Zehnder interferometer(MZI) with two-mode squeezed thermal state(TMSTS). Using the classical transformation rel...Based on the Wigner-function method, we investigate the parity detection and phase sensitivity in a Mach–Zehnder interferometer(MZI) with two-mode squeezed thermal state(TMSTS). Using the classical transformation relation of the MZI, we derive the input–output Wigner functions and then obtain the explicit expressions of parity and phase sensitivity.The results from the numerical calculation show that supersensitivity can be reached only if the input TMSTS have a large number photons.展开更多
We study the higher order fluctuations and squeezing of quadrature operators in the squeezed thermal states. In terms of measured phase operators, we discuss the fluctuations and squeezing of phases in these states....We study the higher order fluctuations and squeezing of quadrature operators in the squeezed thermal states. In terms of measured phase operators, we discuss the fluctuations and squeezing of phases in these states. We conclude that the condition of higher order squeezing for quadrature components of the field is order independent and the fluctuations of measured phase operators are temperature independent.展开更多
Continuous-variable quantum key distribution(CVQKD)can be integrated with thermal states for short-distance wireless quantum communications.However,its performance is usually restricted with the practical thermal nois...Continuous-variable quantum key distribution(CVQKD)can be integrated with thermal states for short-distance wireless quantum communications.However,its performance is usually restricted with the practical thermal noise.We propose a method to improve the security threshold of thermal-state(TS)CVQKD by employing a heralded hybrid linear amplifier(HLA)at the receiver.We find the effect of thermal noise on the HLA-involved scheme in near-and-mid infrared band or terahertz band for direct and reverse reconciliation.Numerical simulations show that the HLA-involved scheme can compensate for the detriment of thermal noise and hence increase the security threshold of TS-CVQKD.In near-and-mid infrared band,security threshold can be extended by 2.1 dB in channel loss for direct reconciliation and 1.6 dB for reverse reconciliation,whereas in terahertz band,security threshold can be slightly enhanced for the gain parameter less than 1 due to the rise in thermal noise.展开更多
The dynamical behavior of a photon-added thermal state(PATS) in a thermal reservoir is investigated by virtue of Wigner function(WF) and Wigner logarithmic negativity(WLN), where this propagation model is abstracted a...The dynamical behavior of a photon-added thermal state(PATS) in a thermal reservoir is investigated by virtue of Wigner function(WF) and Wigner logarithmic negativity(WLN), where this propagation model is abstracted as an input–output problem in a thermal-loss channel. The density operator of the output optical field at arbitrary time can be expressed in the integration form of the characteristics function of the input optical field. The exact analytical expression of WF is given, which is closely related to the Laguerre polynomial and is dependent on the evolution time and other interaction parameters(related with the initial field and the reservoir). Based on the WLN, we observe the dynamical evolution of the PATS in the thermal reservoir. It is shown that the thermal noise will make the PATS lose the non-Gaussianity.展开更多
At present, there is no method for identifying meat frozen in a thermal state acceptable for production control. The role of free nucleotides in the processes of refrigeration and storage of meat, affecting the struct...At present, there is no method for identifying meat frozen in a thermal state acceptable for production control. The role of free nucleotides in the processes of refrigeration and storage of meat, affecting the structural and mechanical properties of muscle tissue, the formation of taste and its biological value is known. In this article we compared methods for identifying the thermal state of meat based on the determination of the composition and content of free nucleotides by high-performance liquid chromatography (HPLC) and spectrophotometry [SF]. High-purity reference substances were used: free nucleotides—ATP, ADP, AMP, IMP and nucleosides-inosine and hypoxanthine. It has been experimentally established that the characteristic peaks of the absorption spectra for extracts of free nucleotides of meat frozen depended from thermal state of meat. The content of ATP is 21.8 times higher in meat frozen in a fresh state, and the amount of IMF is 12.3 times lower than in meat frozen after cooling. The results of studies of meat frozen using the HPLC method and the developed SF method show the adequacy of the data obtained by both methods. SF-method based on the determination of the optical density of the extracts of free nucleotides is recommended to justify the choice of technological process meat defrost modes.展开更多
Using the well-behaved features of the thermal entangled state representation, we solve the diffusion master equation under the action of a linear resonance force, and then obtain the infinitive operator-sum represent...Using the well-behaved features of the thermal entangled state representation, we solve the diffusion master equation under the action of a linear resonance force, and then obtain the infinitive operator-sum representation of the density operator. This approach may also be effective for treating other master equations. Moreover, we find that the initial pure coherent state evolves into a mixed thermal state after passing through the diffusion process under the action of the linear resonance force.展开更多
Combined with the parameters of the production process of a steel factory, numerical simulations for a new ladle from preheating to turnover are conducted using the finite element analysis system software (ANSYS). T...Combined with the parameters of the production process of a steel factory, numerical simulations for a new ladle from preheating to turnover are conducted using the finite element analysis system software (ANSYS). The measured data proved that the simulated results are reliable. The effects of preheating time, thermal cycling times, and empty package time on steel temperature are calculated, an ideal preheating time is provided, besides, based on the analysis of a single factor and use the nonlinear analysis method, a steel temperature compensating model with di- versified coupling factors is proposed, with the largest error of the present coupling model at 1. 462 ~C, and the er- rors between actual and target steel temperature in tundish after the model is applied to practical production are basi- cally controlled within -4-6 ~C, which can meet the accuracy of the manufacturer and has a practical guiding significance for the production in steelmaking workshops.展开更多
Entanglement charge is an operational measure to quantify nonlocalities in ensembles consisting of bipartite quantum states.Here we generalize this nonlocality measure to single bipartite quantum states.As an example,...Entanglement charge is an operational measure to quantify nonlocalities in ensembles consisting of bipartite quantum states.Here we generalize this nonlocality measure to single bipartite quantum states.As an example,we analyze the entanglement charges of some thermal states of two-qubit systems and show how they depend on the temperature and the system parameters in an analytical way.展开更多
The dynamic process of ocean-continent subduction depends on not only the properties of the subducting oceanic plate,but also the characteristics and state of the overriding continental plate.Numerical models conducte...The dynamic process of ocean-continent subduction depends on not only the properties of the subducting oceanic plate,but also the characteristics and state of the overriding continental plate.Numerical models conducted to date have mostly focused on the oceanic lithosphere in this regard;research on the properties of overriding continental lithosphere remains relatively limited,especially the influence of its thermal state on subduction dynamics.Here we explored the performance of continental lithosphere with different thermal states during the subduction process using two-dimensional thermal-mechanical modeling and systematically investigated the effects of the thermal state of overriding continental plate,the age of subducting oceanic plate,and relative convergence rate on subduction dynamics.Modeling results show that:(1)When the geothermal gradient of continental crust is low(between 10 and 15℃km^-1),the oceanic plate first subducts at a low angle.As subduction continues,the slab dip gradually increases and the slab begins to retreat rapidly driven by its negative buoyancy,opening an ocean basin ranging from 600 to 1100 km in width.This leads to the decoupling between the overriding continental plate and oceanic plate.As the trench retreat continues,the horizontal deviatoric stress inside the overriding continental crust alternates between being positive and negative in a local area.Thinning of the overriding lithosphere mainly occurs at the region adjacent to the subduction zone,where the surface experiences significant subsidence.(2)When the geothermal gradient of continental crust is higher(greater than 15℃km-1),oceanic plate retreat causes the overriding continental plate to be strongly stretched.In this case,the trench retreat distance decreases and the width of the ocean basin also reduces by between 100 and 1000 km.The horizontal deviatoric stress inside the whole overriding continental crust first manifests as compression and then changes into extension,which causes the surface to first uplift and then slowly subside.(3)Increasing the age of oceanic lithosphere accelerates trench retreat and promotes overriding plate thinning.(4)An advancing overriding continental plate slows down trench retreat.In cases where the geothermal gradient of continental crust is greater than 17.5℃km-1,the hot continental crust experiences gravitational collapse and is overthrusted onto oceanic lithosphere,resulting in slow trench retreat.We analyzed the subduction process of the western Paleo-Pacific Plate in the Early Cretaceous based on our modeling results and discussed its possible control on the tectonic evolution of the rift basins in east Asia.We suggest that the development of a wide rift basin system on the Amurian Superterrane in the Early Cretaceous was likely related to slow trench retreat and the collapse of the hot crust,and the formation of a series of passive rift basins in the North China Craton was likely caused by the relatively cold thermal state of the lithosphere and the rapid retreat of the Paleo-Pacific Plate.展开更多
The Galilean invariance and the induced thermo-hydrodynamics of the lattice Boltzmann Bhatnagar-Gross-Krook model are proposed together with their rigorous theoretical background. From the viewpoint of group invarianc...The Galilean invariance and the induced thermo-hydrodynamics of the lattice Boltzmann Bhatnagar-Gross-Krook model are proposed together with their rigorous theoretical background. From the viewpoint of group invariance, recovering the Galilean invariance for the isothermal lattice Boltzmann Bhatnagar-Gross-Krook equation (LBGKE) induces a new natural thermal-dynamical system, which is compatible with the elementary statistical thermodynamics.展开更多
This paper presents a method of thermal state calculation of combustion chamber in small thrust liquid rocket engine. The goal is to predict the thermal state of chamber wall by using basic parameters of engine: thrus...This paper presents a method of thermal state calculation of combustion chamber in small thrust liquid rocket engine. The goal is to predict the thermal state of chamber wall by using basic parameters of engine: thrust level, propellants, chamber pressure, injection pattern, film cooling parameters, material of wall and their coating, etc. The difficulties in modeling the startup and shutdown processes of thrusters lie in the fact that there are the conjugated physical processes occurring at various parameters for non-design conditions. A mathematical model to predict the thermal state of the combustion chamber for different engine operation modes is developed. To simulate the startup and shutdown processes, a quasi-steady approach is applied by replacing the transient process with time-variant operating parameters of steady-state processes. The mathematical model is based on several principles and data commonly used for heat transfer modeling: geometry of flow part, gas dynamics of flow, thermodynamics of propellants and combustion spices, convective and radiation heat flows, conjugated heat transfer between hot gas and wall, and transient approach for calculation of thermal state of construction. Calculations of the thermal state of the combustion chamber in single-turn-on mode show good convergence with the experimental results. The results of pulsed modes indicate a large temperature gradient on the internal wall surface of the chamber between pulses and the thermal state of the wall strongly depends on the pulse duration and the interval.展开更多
The thermal equation of state of a natural kyanite has been investigated with a DIA-type,cubic-anvil apparatus(SAM85)combined with an energy-dispersive synchrotron X-ray radiation technique up to 8.55 GPa and 1273 K.N...The thermal equation of state of a natural kyanite has been investigated with a DIA-type,cubic-anvil apparatus(SAM85)combined with an energy-dispersive synchrotron X-ray radiation technique up to 8.55 GPa and 1273 K.No phase transition was observed in the studied pressure-temperature(P-T)range.The Le Bail full profile refinement technique was used to derive the unit-cell parameters.By fixing the bulk modulus K 0 as 196 GPa and its pressure derivative K0 as 4,our P-V(volume)-T data were fitted to the high temperature BircheMurnaghan equation of state.The obtained parameters for the kyanite are:V_(0)=294.05(9)Å^(3),a=2.53(11)×10^(-5)K^(-1) and(K/T)P=-0.021(8)GPa∙K^(-1).These parameters have been combined with other experimentally-measured thermodynamic data for the relevant phases to calculate the P-T locus of the reaction kyanite¼stishoviteþcorundum.With this thermodynamically constrained phase boundary,previous high-pressure phase equi-librium experimental studies with the multi-anvil press have been evaluated.展开更多
We propose a most simple and experimentally feasible scheme for teleporting unknown atomic entangled states in driven cavity quantum electrodynamics (QED). In our scheme, the joint Bell-state measurement (BSM) is ...We propose a most simple and experimentally feasible scheme for teleporting unknown atomic entangled states in driven cavity quantum electrodynamics (QED). In our scheme, the joint Bell-state measurement (BSM) is not required, and the successful probability can reach 1.0. Furthermore, the scheme is insensitive to the cavity decay and the thermal field.展开更多
基金supported by the National Natural Science Foundation of China under Grant No.40275013the National Key Programme for Developing Basic Sciences(G1998040900-part 1)LASG,Institute of Atmospheric Physics,Chinese Academy of Sciences.
文摘This study focuses on the characteristics of the 30 60-day oscillation (MJO) associated with the interannual variability of the thermal state in the western Pacific warm pool. The composite results show that, the amplitude of MJO convection over the tropical western Pacific tends to intensify (reduce) in the WARM (COLD) case. The negative correlations between MJO convection in the WARM and in the COLD cases are examined to be significant over most of the Asian-Pacific region. The evolutions of MJO convection and lower circulation, on the one hand, exhibit larger differences between the WARM and COLD cases, but on the other hand, display a unique feature in that a well-developed MJO cyclone (anticyclone) is anchored over the Asian-Western Pacific domain at the peak enhanced (suppressed) MJO convection phase over the western Pacific warm pool, either in the WARM or in the COLD case. This unique feature of MJO shows a Gill-type response of lower circulation to the convection and is inferred to be an inherent appearance of MJO. The context in the paper suggests there may exist interactions between MJO and the interannual variability of the thermal state in the western Pacific warm pool.
基金Supported by Hunan Provincial Natural Science Foundation of China under Grant No.10JJ6010the Key Project Foundation of Hunan Provincial Education Department of China under Grant No.10A095
文摘We study a system consisting of two identical non-interacting single-mode cavity fields coupled to a common vacuum environment and provide general, explicit, and exact solutions to its master equation by means of the characteristic function method. We analyze the entanglement dynamics of two-mode squeezed thermal state in this model and show that its entanglement dynamics is strongly determined by the two-mode squeezing parameter and the purity. In particular, we find that two-mode squeezed thermal state with the squeezing parameter r ≤ -(1/2) In √u is extremely fragile and almost does not survive in a common vacuum environment. We investigate the time evolution of nonlocality for two-mode squeezed thermal state in such an environment. It is found that the evolved state loses its nonlocality in the beginning of the evolution, but after a time, the revival of nonlocality can occur.
基金Project supported by the National Natural Science Foundation of China(Grant No.11347026)the Natural Science Foundation of Shandong Province,China(Grant Nos.ZR2016AM03 and ZR2017MA011)
文摘We investigate how displaced thermal states (DTSs) evolve in a laser channel. Remarkably, the initial DTS, an example of a mixed state, still remains mixed and thermal. At long times, they finally decay to a highly classical thermal field only related to the laser parameters κ and g. The normal ordering product of density operator of the DTS in the laser channel leads to obtaining the analytical time-evolution expressions of the photon number, Wigner function, and von Neumann entropy. Also, some interesting results are presented via numerically investigating these explicit time-dependent expressions.
文摘In the coherent thermal state representation we introduce thermal Wigner operator and find that it is'squeezed' under the thermal transformation. The thermal Wigner operator provides us with a new direct and neatapproach for deriving Wigner functions of thermal states.
基金Project supported by the National Natural Science Foundation of China (Grant Nos 10775097 and 10874174)the Research Foundation of the Education Department of Jiangxi Province of China
文摘By using the technique of integration within an ordered product of operators, the normal ordered density operator of the photon-subtracted squeezed thermal state (PSSTS) is derived. Then the corresponding Wigner function is presented by using the coherent state representation of the Wigner operator. The nonclassical properties of the PSSTS are discussed based on the negativity of the Wigner function.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 11264018 and 60978009)the Major Research Plan of the National Natural Science Foundation of China (Grant No. 91121023)+1 种基金the National Basic Research Project of China (Grant No. 2011CBA00200)the Young Talents Foundation of Jiangxi Normal University,China
文摘For the first time,we derive the compact forms of normalization factors for photon-added(-subtracted) two-mode squeezed thermal states by using the P-representation and the integration within an ordered product of operators(IWOP) technique.It is found that these two factors are related to the Jacobi polynomials.In addition,some new relationships for Jacobi polynomials are presented.
基金the President Foundation of the Chinese Academy of Sciences
文摘We employ the coherent thermal states(a kind of entangled states)in thermal field dynamics to establisha complete entangled state formalism expressing pseudo-classical representations of density operator for light field.Especially,the relationship between the coherent thermal state and the characteristic function and the positive Prepresentation in quantum optics theory are obtained.
基金supported by the National Natural Science Foundation of China(Grant No.11447002)the Research Foundation of the Education Department of Jiangxi Province of China(Grant No.GJJ150338)the Research Foundation for Changzhou Institute of Modern Optoelectronic Technology(Grant No.CZGY15)
文摘Based on the Wigner-function method, we investigate the parity detection and phase sensitivity in a Mach–Zehnder interferometer(MZI) with two-mode squeezed thermal state(TMSTS). Using the classical transformation relation of the MZI, we derive the input–output Wigner functions and then obtain the explicit expressions of parity and phase sensitivity.The results from the numerical calculation show that supersensitivity can be reached only if the input TMSTS have a large number photons.
文摘We study the higher order fluctuations and squeezing of quadrature operators in the squeezed thermal states. In terms of measured phase operators, we discuss the fluctuations and squeezing of phases in these states. We conclude that the condition of higher order squeezing for quadrature components of the field is order independent and the fluctuations of measured phase operators are temperature independent.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61572529 and 61871407).
文摘Continuous-variable quantum key distribution(CVQKD)can be integrated with thermal states for short-distance wireless quantum communications.However,its performance is usually restricted with the practical thermal noise.We propose a method to improve the security threshold of thermal-state(TS)CVQKD by employing a heralded hybrid linear amplifier(HLA)at the receiver.We find the effect of thermal noise on the HLA-involved scheme in near-and-mid infrared band or terahertz band for direct and reverse reconciliation.Numerical simulations show that the HLA-involved scheme can compensate for the detriment of thermal noise and hence increase the security threshold of TS-CVQKD.In near-and-mid infrared band,security threshold can be extended by 2.1 dB in channel loss for direct reconciliation and 1.6 dB for reverse reconciliation,whereas in terahertz band,security threshold can be slightly enhanced for the gain parameter less than 1 due to the rise in thermal noise.
基金Project supported by the National Natural Science Foundation of China(Grant No.11665013)
文摘The dynamical behavior of a photon-added thermal state(PATS) in a thermal reservoir is investigated by virtue of Wigner function(WF) and Wigner logarithmic negativity(WLN), where this propagation model is abstracted as an input–output problem in a thermal-loss channel. The density operator of the output optical field at arbitrary time can be expressed in the integration form of the characteristics function of the input optical field. The exact analytical expression of WF is given, which is closely related to the Laguerre polynomial and is dependent on the evolution time and other interaction parameters(related with the initial field and the reservoir). Based on the WLN, we observe the dynamical evolution of the PATS in the thermal reservoir. It is shown that the thermal noise will make the PATS lose the non-Gaussianity.
文摘At present, there is no method for identifying meat frozen in a thermal state acceptable for production control. The role of free nucleotides in the processes of refrigeration and storage of meat, affecting the structural and mechanical properties of muscle tissue, the formation of taste and its biological value is known. In this article we compared methods for identifying the thermal state of meat based on the determination of the composition and content of free nucleotides by high-performance liquid chromatography (HPLC) and spectrophotometry [SF]. High-purity reference substances were used: free nucleotides—ATP, ADP, AMP, IMP and nucleosides-inosine and hypoxanthine. It has been experimentally established that the characteristic peaks of the absorption spectra for extracts of free nucleotides of meat frozen depended from thermal state of meat. The content of ATP is 21.8 times higher in meat frozen in a fresh state, and the amount of IMF is 12.3 times lower than in meat frozen after cooling. The results of studies of meat frozen using the HPLC method and the developed SF method show the adequacy of the data obtained by both methods. SF-method based on the determination of the optical density of the extracts of free nucleotides is recommended to justify the choice of technological process meat defrost modes.
基金supported by the National Natural Science Foundation of China(Grant Nos.11347026,11147009,and 11244005)the Natural Science Foundation of Shandong Province,China(Grant Nos.ZR2013AM012 and ZR2012AM004)the Scientific Research Project of Liaocheng,China
文摘Using the well-behaved features of the thermal entangled state representation, we solve the diffusion master equation under the action of a linear resonance force, and then obtain the infinitive operator-sum representation of the density operator. This approach may also be effective for treating other master equations. Moreover, we find that the initial pure coherent state evolves into a mixed thermal state after passing through the diffusion process under the action of the linear resonance force.
基金Item Sponsored by Technology Supporting Program During the 11th Five-Year Plan Period(BAE03A07)
文摘Combined with the parameters of the production process of a steel factory, numerical simulations for a new ladle from preheating to turnover are conducted using the finite element analysis system software (ANSYS). The measured data proved that the simulated results are reliable. The effects of preheating time, thermal cycling times, and empty package time on steel temperature are calculated, an ideal preheating time is provided, besides, based on the analysis of a single factor and use the nonlinear analysis method, a steel temperature compensating model with di- versified coupling factors is proposed, with the largest error of the present coupling model at 1. 462 ~C, and the er- rors between actual and target steel temperature in tundish after the model is applied to practical production are basi- cally controlled within -4-6 ~C, which can meet the accuracy of the manufacturer and has a practical guiding significance for the production in steelmaking workshops.
基金supported by the National Natural Science Foundation of China (Grant Nos. 60878059,11004033 and 10905016)the Natural Science Foundation of Fujian Province (Grant No. 2010J01002)+2 种基金the Fundof Hebei Normal University,the RGC Grant of Hong Kong (Grant Nos.HKU7044/08P and HKU7058/11P)the State Key Program for Basic Research of China (Grant No. 2011CB922104)the National Fundamental Research Program of China (Grant No. 2011CBA00203)
文摘Entanglement charge is an operational measure to quantify nonlocalities in ensembles consisting of bipartite quantum states.Here we generalize this nonlocality measure to single bipartite quantum states.As an example,we analyze the entanglement charges of some thermal states of two-qubit systems and show how they depend on the temperature and the system parameters in an analytical way.
基金supported by the National Key Research and Development of China(Grant No.2016YFC0600406)the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(Grant No.XDB18000000)。
文摘The dynamic process of ocean-continent subduction depends on not only the properties of the subducting oceanic plate,but also the characteristics and state of the overriding continental plate.Numerical models conducted to date have mostly focused on the oceanic lithosphere in this regard;research on the properties of overriding continental lithosphere remains relatively limited,especially the influence of its thermal state on subduction dynamics.Here we explored the performance of continental lithosphere with different thermal states during the subduction process using two-dimensional thermal-mechanical modeling and systematically investigated the effects of the thermal state of overriding continental plate,the age of subducting oceanic plate,and relative convergence rate on subduction dynamics.Modeling results show that:(1)When the geothermal gradient of continental crust is low(between 10 and 15℃km^-1),the oceanic plate first subducts at a low angle.As subduction continues,the slab dip gradually increases and the slab begins to retreat rapidly driven by its negative buoyancy,opening an ocean basin ranging from 600 to 1100 km in width.This leads to the decoupling between the overriding continental plate and oceanic plate.As the trench retreat continues,the horizontal deviatoric stress inside the overriding continental crust alternates between being positive and negative in a local area.Thinning of the overriding lithosphere mainly occurs at the region adjacent to the subduction zone,where the surface experiences significant subsidence.(2)When the geothermal gradient of continental crust is higher(greater than 15℃km-1),oceanic plate retreat causes the overriding continental plate to be strongly stretched.In this case,the trench retreat distance decreases and the width of the ocean basin also reduces by between 100 and 1000 km.The horizontal deviatoric stress inside the whole overriding continental crust first manifests as compression and then changes into extension,which causes the surface to first uplift and then slowly subside.(3)Increasing the age of oceanic lithosphere accelerates trench retreat and promotes overriding plate thinning.(4)An advancing overriding continental plate slows down trench retreat.In cases where the geothermal gradient of continental crust is greater than 17.5℃km-1,the hot continental crust experiences gravitational collapse and is overthrusted onto oceanic lithosphere,resulting in slow trench retreat.We analyzed the subduction process of the western Paleo-Pacific Plate in the Early Cretaceous based on our modeling results and discussed its possible control on the tectonic evolution of the rift basins in east Asia.We suggest that the development of a wide rift basin system on the Amurian Superterrane in the Early Cretaceous was likely related to slow trench retreat and the collapse of the hot crust,and the formation of a series of passive rift basins in the North China Craton was likely caused by the relatively cold thermal state of the lithosphere and the rapid retreat of the Paleo-Pacific Plate.
基金Project supported by the National Natural Science Foundation of China (Grant Nos 90816013 and 10572083)Shanghai Leading Academic Discipline Project,China (Grant No Y0103)
文摘The Galilean invariance and the induced thermo-hydrodynamics of the lattice Boltzmann Bhatnagar-Gross-Krook model are proposed together with their rigorous theoretical background. From the viewpoint of group invariance, recovering the Galilean invariance for the isothermal lattice Boltzmann Bhatnagar-Gross-Krook equation (LBGKE) induces a new natural thermal-dynamical system, which is compatible with the elementary statistical thermodynamics.
文摘This paper presents a method of thermal state calculation of combustion chamber in small thrust liquid rocket engine. The goal is to predict the thermal state of chamber wall by using basic parameters of engine: thrust level, propellants, chamber pressure, injection pattern, film cooling parameters, material of wall and their coating, etc. The difficulties in modeling the startup and shutdown processes of thrusters lie in the fact that there are the conjugated physical processes occurring at various parameters for non-design conditions. A mathematical model to predict the thermal state of the combustion chamber for different engine operation modes is developed. To simulate the startup and shutdown processes, a quasi-steady approach is applied by replacing the transient process with time-variant operating parameters of steady-state processes. The mathematical model is based on several principles and data commonly used for heat transfer modeling: geometry of flow part, gas dynamics of flow, thermodynamics of propellants and combustion spices, convective and radiation heat flows, conjugated heat transfer between hot gas and wall, and transient approach for calculation of thermal state of construction. Calculations of the thermal state of the combustion chamber in single-turn-on mode show good convergence with the experimental results. The results of pulsed modes indicate a large temperature gradient on the internal wall surface of the chamber between pulses and the thermal state of the wall strongly depends on the pulse duration and the interval.
基金This work is financially supported by the Natural Science Foundation of China(Grant No.41273072)by the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(XDB18030602).
文摘The thermal equation of state of a natural kyanite has been investigated with a DIA-type,cubic-anvil apparatus(SAM85)combined with an energy-dispersive synchrotron X-ray radiation technique up to 8.55 GPa and 1273 K.No phase transition was observed in the studied pressure-temperature(P-T)range.The Le Bail full profile refinement technique was used to derive the unit-cell parameters.By fixing the bulk modulus K 0 as 196 GPa and its pressure derivative K0 as 4,our P-V(volume)-T data were fitted to the high temperature BircheMurnaghan equation of state.The obtained parameters for the kyanite are:V_(0)=294.05(9)Å^(3),a=2.53(11)×10^(-5)K^(-1) and(K/T)P=-0.021(8)GPa∙K^(-1).These parameters have been combined with other experimentally-measured thermodynamic data for the relevant phases to calculate the P-T locus of the reaction kyanite¼stishoviteþcorundum.With this thermodynamically constrained phase boundary,previous high-pressure phase equi-librium experimental studies with the multi-anvil press have been evaluated.
基金Project supported by the National Natural Science Foundation of China (Grant No 10374025).
文摘We propose a most simple and experimentally feasible scheme for teleporting unknown atomic entangled states in driven cavity quantum electrodynamics (QED). In our scheme, the joint Bell-state measurement (BSM) is not required, and the successful probability can reach 1.0. Furthermore, the scheme is insensitive to the cavity decay and the thermal field.