A compact four-component two-dimensional （2-D） finite-difference frequency domain （FDFD） method with the equivalent surface impedance boundary condition is used to analyze the dispersion characteristics of multila...A compact four-component two-dimensional （2-D） finite-difference frequency domain （FDFD） method with the equivalent surface impedance boundary condition is used to analyze the dispersion characteristics of multilayer metal-coated waveguides. According to the equivalent surface impedance boundary condition,the relationship between transverse field components on the boundary can be easily depicted. Once the eigen equation is solved,the propagation constant can be obtained as the eigen value for a given frequency. Results of the proposed method agaree well with those of high frequency structure simulator（HFSS）.展开更多
In this paper,we discussed a slab wave-guide of five layers,The core is a left-handed material,but the claddings are right-handed materials. A dispersion equation of TE modes is obtained by using Maxwell's equatio...In this paper,we discussed a slab wave-guide of five layers,The core is a left-handed material,but the claddings are right-handed materials. A dispersion equation of TE modes is obtained by using Maxwell's equations,and some new dispersion characteristics are obtained based on the equation.展开更多
Based on couple wave equation and finite-difference time-domain (FDTD) algorithm,the strong couple characteristic of 2-D photonic crystal couplers is calculated.Theoretical analysis and numerical simulated results ind...Based on couple wave equation and finite-difference time-domain (FDTD) algorithm,the strong couple characteristic of 2-D photonic crystal couplers is calculated.Theoretical analysis and numerical simulated results indicate that the energy in a 2-D photonic crystal coupler can not be totally transferred between two wave-guides.Compared with the result of weak coupling theory,our result is more accurate.展开更多
We study the WKB dispersion equation in non-uniform optical waveguide.There are three methods given in this paper:(1) method of Airy function;(2)method of connection formula;and(3) method of phase shift.At last we mak...We study the WKB dispersion equation in non-uniform optical waveguide.There are three methods given in this paper:(1) method of Airy function;(2)method of connection formula;and(3) method of phase shift.At last we make some remarks.展开更多
Since the adverse factors such as deficient penetration and long reaction time have restricted the complete microwave-used drying of municipal sludge, the microwave-induced drying is considered, which has advantages i...Since the adverse factors such as deficient penetration and long reaction time have restricted the complete microwave-used drying of municipal sludge, the microwave-induced drying is considered, which has advantages in such aspects. The investigation of the microwave-induced drying to uncover the mechanism bears great meaning for its development and utilization. The effects of temperature and microwave cracking in municipal sewage sludge drying characteristics are stud- ied through municipal sewage sludge drying experiment. Experiments shows that higher drying temperature would lead to a more acutely changing drying rate （DR）. The DR had increased from 0.005 g/（g.min） to 0.060 g/（g·min）, which was 12 times enlarged, while the temperature rose from 70℃ to 160 ℃. The higher the temperature was, the earlier the peak value of DR appeared. The experiments indicated that the temperature was the decisive factor affecting the DR. The microwave-induced sludge reached the highest DR at the moisture rate （MR） of 40%, with a 20% grade promotion compared with that of the original one. The molecular fracture caused by microwave radiation had obviously accelerated the drying process and the DR was rising in proportion to the microwave radiation dose. The diffusion coefficient had been calculated according to Fick＇s law. In com- parison to that of the original one, the diffusion coefficient of microwave-induced sludge was obviously enlarged more than two times. By fit examinations, Model Weibull was proven to be the most fit one for thermal thin-layer drying of municipal sludge. By means of Arrhenius equation, the obtained average activation energy of municipal sludge was 37.1 kJ/（mol·K）.展开更多
In this paper, we try to present a way in terms of which one can analytically obtain the Hartree selfconsistent potential instead of computing it by the numerical iterative procedure as usual, which is convenient for ...In this paper, we try to present a way in terms of which one can analytically obtain the Hartree selfconsistent potential instead of computing it by the numerical iterative procedure as usual, which is convenient for us to describe the current flow through a mesoscopic conductor. In our treatment, we expand the action function S(x)by Planck constant h, then the self-consistent potential and the wavefunction can be solved analytically order by order starting from the Poisson equation and quantum Hamilton-Jacobian equation, the differential conductance and quantum capacitance can thus be obtained naturally. In our paper, we show the quantum corrections up to the second order, and the electron-electron interaction is considered only at the Hartree approximation level.展开更多
We develop a master equation approach to describe the dynamics of distant resonators coupled through a one-dimensional waveguide. Our method takes into account the back-actions of the reservoirs, and enables us to cal...We develop a master equation approach to describe the dynamics of distant resonators coupled through a one-dimensional waveguide. Our method takes into account the back-actions of the reservoirs, and enables us to calculate the exact dynamics of the complete system at all times. We show that such system can cause nonexponential and long-lived photon decay due to the existence of a relaxation effect. The physical origin of non-Markovianity in our model system is the finite propagation speed resulting in time delays in communication between the nodes, and strong decay rate of the emitters into the waveguide. When the distance satisfies the standing wave condition, we find that when the time delay is increased, the dark modes formation is no longer perfect, and the average photon number of dark mode decreases in steady time limit.展开更多
The average-passage equation system(APES)provides a rigorous framework to account for the deterministic unsteady effects by the so-called deterministic correlations(DC),which include both deterministic stress correlat...The average-passage equation system(APES)provides a rigorous framework to account for the deterministic unsteady effects by the so-called deterministic correlations(DC),which include both deterministic stress correlations(DCS)and deterministic total enthalpy correlations(DCH).These correlations should be modeled to close the system of equations.In this paper,the distribution of DC in a transonic centrifugal compressor is presented,and its relative importance is revealed.The assumption made by Adamczyk that the pure unsteady fluctuation is significantly smaller than the spatial fluctuation is verified at the impeller-diffuser interface.The decomposition of DCH is also discussed to determine its two different physical mechanisms.Finally,the transport equations in terms of DCS in cylindrical coordinates are derived,and the terms are evaluated to determine the ones that are necessary to model.All these analyses significantly contribute to our model development for DC in centrifugal compressors.展开更多
The diffusive thermal conductivity tensor of p-wave superfluid at low temperatures is calculated by using the Boltzmann equation approach. We use the Sykes and Brooker procedure and show that Kxx is equal to Kyy and t...The diffusive thermal conductivity tensor of p-wave superfluid at low temperatures is calculated by using the Boltzmann equation approach. We use the Sykes and Brooker procedure and show that Kxx is equal to Kyy and these are related to T-1, also Kxx is proporated to T-3.展开更多
基金Supported by the Project Innovation of Graduate Students of Jiangsu Province of China(CX09B-079Z)the Basic Research Items of National Key Lab of Electronic Measurement Technology~~
文摘A compact four-component two-dimensional （2-D） finite-difference frequency domain （FDFD） method with the equivalent surface impedance boundary condition is used to analyze the dispersion characteristics of multilayer metal-coated waveguides. According to the equivalent surface impedance boundary condition,the relationship between transverse field components on the boundary can be easily depicted. Once the eigen equation is solved,the propagation constant can be obtained as the eigen value for a given frequency. Results of the proposed method agaree well with those of high frequency structure simulator（HFSS）.
基金Shanghai Leading Academic Disci- pline Project (T0102)Creative Graduate Student Foundation of Shanghai University (A.16-0107-07-001)
文摘In this paper,we discussed a slab wave-guide of five layers,The core is a left-handed material,but the claddings are right-handed materials. A dispersion equation of TE modes is obtained by using Maxwell's equations,and some new dispersion characteristics are obtained based on the equation.
基金Supported by the Youth Science and Technology InnovationItem Foundation of Fujian Province(2001J008)
文摘Based on couple wave equation and finite-difference time-domain (FDTD) algorithm,the strong couple characteristic of 2-D photonic crystal couplers is calculated.Theoretical analysis and numerical simulated results indicate that the energy in a 2-D photonic crystal coupler can not be totally transferred between two wave-guides.Compared with the result of weak coupling theory,our result is more accurate.
文摘We study the WKB dispersion equation in non-uniform optical waveguide.There are three methods given in this paper:(1) method of Airy function;(2)method of connection formula;and(3) method of phase shift.At last we make some remarks.
基金Supported by the National Nature Science Foundation of China （50930006） Acknowledgment The authors thank Shenzhen Water Group Co., Ltd. （China） for their support for this project and also Si Yaohui, Ph.D., for his assistance.
文摘Since the adverse factors such as deficient penetration and long reaction time have restricted the complete microwave-used drying of municipal sludge, the microwave-induced drying is considered, which has advantages in such aspects. The investigation of the microwave-induced drying to uncover the mechanism bears great meaning for its development and utilization. The effects of temperature and microwave cracking in municipal sewage sludge drying characteristics are stud- ied through municipal sewage sludge drying experiment. Experiments shows that higher drying temperature would lead to a more acutely changing drying rate （DR）. The DR had increased from 0.005 g/（g.min） to 0.060 g/（g·min）, which was 12 times enlarged, while the temperature rose from 70℃ to 160 ℃. The higher the temperature was, the earlier the peak value of DR appeared. The experiments indicated that the temperature was the decisive factor affecting the DR. The microwave-induced sludge reached the highest DR at the moisture rate （MR） of 40%, with a 20% grade promotion compared with that of the original one. The molecular fracture caused by microwave radiation had obviously accelerated the drying process and the DR was rising in proportion to the microwave radiation dose. The diffusion coefficient had been calculated according to Fick＇s law. In com- parison to that of the original one, the diffusion coefficient of microwave-induced sludge was obviously enlarged more than two times. By fit examinations, Model Weibull was proven to be the most fit one for thermal thin-layer drying of municipal sludge. By means of Arrhenius equation, the obtained average activation energy of municipal sludge was 37.1 kJ/（mol·K）.
文摘In this paper, we try to present a way in terms of which one can analytically obtain the Hartree selfconsistent potential instead of computing it by the numerical iterative procedure as usual, which is convenient for us to describe the current flow through a mesoscopic conductor. In our treatment, we expand the action function S(x)by Planck constant h, then the self-consistent potential and the wavefunction can be solved analytically order by order starting from the Poisson equation and quantum Hamilton-Jacobian equation, the differential conductance and quantum capacitance can thus be obtained naturally. In our paper, we show the quantum corrections up to the second order, and the electron-electron interaction is considered only at the Hartree approximation level.
基金Supported by the National Natural Science Foundation of China under Grant Nos.11574041,11475037,and 11704026
文摘We develop a master equation approach to describe the dynamics of distant resonators coupled through a one-dimensional waveguide. Our method takes into account the back-actions of the reservoirs, and enables us to calculate the exact dynamics of the complete system at all times. We show that such system can cause nonexponential and long-lived photon decay due to the existence of a relaxation effect. The physical origin of non-Markovianity in our model system is the finite propagation speed resulting in time delays in communication between the nodes, and strong decay rate of the emitters into the waveguide. When the distance satisfies the standing wave condition, we find that when the time delay is increased, the dark modes formation is no longer perfect, and the average photon number of dark mode decreases in steady time limit.
基金supported by the National Natural Science Foundation of China(Grant Nos.51376001,51006006,51420105008 and 51376014)the National Basic Research Program of China("973"Project)(Grant Nos.2012CB720205,2014CB046405)+2 种基金the Aeronautical Science Foundation of China(Grant No.2012ZB51014)the Beijing Higher Education Young Elite Teacher Projectthe Fundamental Research Funds for the Central Universities
文摘The average-passage equation system(APES)provides a rigorous framework to account for the deterministic unsteady effects by the so-called deterministic correlations(DC),which include both deterministic stress correlations(DCS)and deterministic total enthalpy correlations(DCH).These correlations should be modeled to close the system of equations.In this paper,the distribution of DC in a transonic centrifugal compressor is presented,and its relative importance is revealed.The assumption made by Adamczyk that the pure unsteady fluctuation is significantly smaller than the spatial fluctuation is verified at the impeller-diffuser interface.The decomposition of DCH is also discussed to determine its two different physical mechanisms.Finally,the transport equations in terms of DCS in cylindrical coordinates are derived,and the terms are evaluated to determine the ones that are necessary to model.All these analyses significantly contribute to our model development for DC in centrifugal compressors.
文摘The diffusive thermal conductivity tensor of p-wave superfluid at low temperatures is calculated by using the Boltzmann equation approach. We use the Sykes and Brooker procedure and show that Kxx is equal to Kyy and these are related to T-1, also Kxx is proporated to T-3.
