Combined bodies of rock-like material and rock are widely encountered in geotechnical engineering,such as tunnels and mines.The existing theoretical models describing the stress-strain relationship of a combined body ...Combined bodies of rock-like material and rock are widely encountered in geotechnical engineering,such as tunnels and mines.The existing theoretical models describing the stress-strain relationship of a combined body lack a binary feature.Based on effective medium theory,this paper presents the governing equation of the“elastic modulus”for combined and single bodies under triaxial compressive tests.A binary effective medium model is then established.Based on the compressive experiment of concretegranite combined bodies,the feasibility of determining the stress threshold based on crack axial strain is discussed,and the model is verified.The model is further extended to coal-rock combined bodies of more diverse types,and the variation laws of the compressive mechanical parameters are then discussed.The results show that the fitting accuracy of the model with the experimental curves of the concretegranite combined bodies and various types of coal-rock combined bodies are over 95%.The crack axial strain method can replace the crack volumetric strain method,which clarifies the physical meanings of the model parameters.The variation laws of matrix parameters and crack parameters are discussed in depth and are expected to be more widely used in geotechnical engineering.展开更多
A calculation model based on effective medium theory has been developed for predicting elastic properties of dry carbonates with complex pore structures by integrating the Kuster-Toksǒz model with a differential meth...A calculation model based on effective medium theory has been developed for predicting elastic properties of dry carbonates with complex pore structures by integrating the Kuster-Toksǒz model with a differential method.All types of pores are simultaneously introduced to the composite during the differential iteration process according to the ratio of their volume fractions.Based on this model,the effects of pore structures on predicted pore-pressure in carbonates were analyzed.Calculation results indicate that cracks with low pore aspect ratios lead to pore-pressure overestimation which results in lost circulation and reservoir damage.However,moldic pores and vugs with high pore aspect ratios lead to pore-pressure underestimation which results in well kick and even blowout.The pore-pressure deviation due to cracks and moldic pores increases with an increase in porosity.For carbonates with complex pore structures,adopting conventional pore-pressure prediction methods and casing program designs will expose the well drilling engineering to high uncertainties.Velocity prediction models considering the influence of pore structure need to be built to improve the reliability and accuracy of pore-pressure prediction in carbonates.展开更多
A novel optimal design of sub-wavelength metal rectangular gratings for the polarizing beam splitter (PBS) is proposed. The method is based on effective medium theory and the method of designing single layer antiref...A novel optimal design of sub-wavelength metal rectangular gratings for the polarizing beam splitter (PBS) is proposed. The method is based on effective medium theory and the method of designing single layer antireflection coating. The polarization performance of PBS is discussed by rigorous couple-wave analysis (RCWA) method at a wavelength of 1550 nm. The result shows that sub-wavelength metal rectangular grating is characterized by a high reflectivity, like metal films for TE polarization, and high transmissivity, like dielectric films for TM polarization. The optimal design accords well with the results simulated by RCWA method.展开更多
We build the perturbation expansion method for nonlinear composite media and extend the EMA for nonlinear effective conductivity. Using the solutions of boundary-value problems of a cylindrical in- clusion, we derive ...We build the perturbation expansion method for nonlinear composite media and extend the EMA for nonlinear effective conductivity. Using the solutions of boundary-value problems of a cylindrical in- clusion, we derive formulae for nonlinear effective conductivity.展开更多
In this study, we illustrate the effective medium theories in the designs of three-dimensional composite metama- terials of both negative permittivity and negative permeability. The proposed metamaterial consists of r...In this study, we illustrate the effective medium theories in the designs of three-dimensional composite metama- terials of both negative permittivity and negative permeability. The proposed metamaterial consists of random coated spheres with sizes smaller compared to the wavelength embedded in a dielectric host. Simple design rules and formulas following the effective medium models are numerically and analytically presented. We demonstrate that the revised Maxwell-Garnett effective medium theory enables us to design three-dimensional composite metamaterials through the assembly of coated spheres which are random and much smaller than the wavelength of the light. The proposed ap- proach allows for the precise control of the permittivity and the permeability and guides a facile, flexible, and versatile way for the fabrication of composite metamaterials.展开更多
An ultrathin angle-insensitive color filter enabling high color saturation and a wide color gamut is proposed by relying on magnesium hydride-hydrogenated amorphous silicon[MgH2-a-Si:H]lossy dielectric layer.Based on ...An ultrathin angle-insensitive color filter enabling high color saturation and a wide color gamut is proposed by relying on magnesium hydride-hydrogenated amorphous silicon[MgH2-a-Si:H]lossy dielectric layer.Based on effective medium theory,the MgH2-a-Si:H layer with an ultrathin thickness can be equivalent to a quasi-homogeneous dielectric layer wit an effective complex refractive index,which can be tuned by altering the thickness of MgH2to obtain the targeted value o the imaginary part,corresponding to the realization of high color saturation.It is verified that the proposed color filte offers highly enhanced color saturation in conjunction with a wide color gamut by introducing a few-nanometer thic MgH2layer.As the MgH2-a-Si:H layer retains the advantages of high refractive index and tiny thickness,the proposed colo filter exhibits large angular tolerance up to±60°.In addition,MgH2with an unstable property can interconvert with Mg unde a dehydrogenation/hydrogenation reaction,which empowers the proposed color filter with dynamically tunable outpu color.The proposed scheme shows great promise in color printing and ultracompact display devices with high color sat uration,wide gamut,large angular tolerance,and dynamic tunability.展开更多
Ultrathin planar absorbers hold promise in solar energy systems because they can reduce the material, fabrication, and system cost. Here, we present a general strategy of effective medium design to realize ultrathin p...Ultrathin planar absorbers hold promise in solar energy systems because they can reduce the material, fabrication, and system cost. Here, we present a general strategy of effective medium design to realize ultrathin planar broadband absorbers. The absorber consists of two ultrathin absorbing dielectrics to design an effective absorbing medium, a transparent layer, and metallic substrate. Compared with previous studies, this strategy provides another dimension of freedom to enhance optical absorption; therefore, destructive interference can be realized over a broad spectrum. To demonstrate the power and simplicity of this strategy, we both experimentally and theoretically characterized an absorber with 5-nm-thick Ge, 10-nm-thick Ti, and 50-nm-thick SiO2 films coated on an Ag substrate fabricated using simple deposition methods. Absorptivity higher than 80% was achieved in 15-nm-thick (1/50 of the center wavelength) Ge and Ti films from 400 nm to near 1 btm. As an application example, we experimentally demonstrated that the absorber exhibited a normal solar absorptivity of 0.8 with a normal emittance of 0.1 at 500 ~C, thus demonstrating its potential in solar thermal systems. The effective medium design strategy is general and allows material versatility, suggesting possible applications in real-time optical manipulation using dynamic materials.展开更多
Effective medium theory is a powerful tool to solve various problems for achieving multifarious functionalities and applications. In this article, we present a concise empirical formula about effective permittivity of...Effective medium theory is a powerful tool to solve various problems for achieving multifarious functionalities and applications. In this article, we present a concise empirical formula about effective permittivity of checkboard structures for different directions. To verify our empirical formula, we perform simulations of checkboard periodic structures in squares, rectangles, and sectors in two dimensions. Our results show that the formula is valid in a large range of parameters. This work provides a new way to understand and design composite materials, which might lead to further optical applications in transformation optics.展开更多
This paper deals with the magnetohydrodynamic (MHD) flow of an Oldroyd 8-constant fluid in a porous medium when no-slip condition is no longer valid. Modified Darcy's law is used in the flow modelling. The non-line...This paper deals with the magnetohydrodynamic (MHD) flow of an Oldroyd 8-constant fluid in a porous medium when no-slip condition is no longer valid. Modified Darcy's law is used in the flow modelling. The non-linear differential equation with non-linear boundary conditions is solved numerically using finite difference scheme in combination with an iterative technique. Numerical results are obtained for the Couette, Poiseuille and generalized Couette flows. The effects of slip parameters on the velocity profile are discussed.展开更多
We investigate a hybrid optomechanical system consisting of two coupled cavities, one of them is composed of two-end fixed mirrors (called the traditional cavity), and the other has a one-end oscillating mirror (na...We investigate a hybrid optomechanical system consisting of two coupled cavities, one of them is composed of two-end fixed mirrors (called the traditional cavity), and the other has a one-end oscillating mirror (named as the optomechanical cavity). A Kerr medium is inside the traditional cavity to enhance the nonlinearity due to the fact that it can cause observing of bistable behavior in intracavity intensity for the optomechanical cavity. The Hamiltonian of the system is written in a rotating frame and its dynamics is described by quantum Langevin equations of motion. Our proposed system exhibits unconventional plots for the mean photon number of the optomechanical cavity which are not observed in previous works. The present results show a deep effect of the Kerr medium on optical bistability of intracavity intensity for the optomechanical cavity. Also, coupling strength of the cavities can effectively change the stability of the system.展开更多
The effect of the solid matrix and porosity of the porous medium are first introduced to the study of power-law nanofluids, and the Marangoni boundary layer flow with heat generation is investigated. Two cases of soli...The effect of the solid matrix and porosity of the porous medium are first introduced to the study of power-law nanofluids, and the Marangoni boundary layer flow with heat generation is investigated. Two cases of solid matrix of porous medium including glass balls and aluminum foam are considered. The governing partial differential equations are simplified by dimensionless variables and similarity transformations, and are solved numerically by using a shooting method with the fourth-fifth-order Runge-Kutta integration technique. It is indicated that the increase of the porosity leads to the enhancement of heat transfer in the surface of the Marangoni boundary layer flow.展开更多
The effect of TPA, a potent tumor promoter, on SSV-NIH3T3 cells in serum-free medium was investigated. TPA stimulated DNA synthesis of SSV-NIH3T3 cells on the third day of culture in SFM. In SDS-PAGF of medium conditi...The effect of TPA, a potent tumor promoter, on SSV-NIH3T3 cells in serum-free medium was investigated. TPA stimulated DNA synthesis of SSV-NIH3T3 cells on the third day of culture in SFM. In SDS-PAGF of medium conditioned by TPA-treated SSV-NIH3T3 cells (in SFM+TPA), the amounts of four proteins of 31.0 Kd, 28.5 Kd, 25.5 Kd and 13.5 Kd strikingly increased over that of non-TPA-treated counterpart (in SFM). The PDGF-like activity was also detected in CM of SFM+TPA. When insulin and EGF were drown off the SFM+TPA (SFM-Ins-EGF+TPA), TPA lost its ability to stimulate DNA synthesis of SSV-NIH3T3 cells on the third day and SDS-PAGE of the conditioned medium showed that the amounts of the four proteins noted above grately reduced. However, cells in SFM-Ins-EGF+TPA were in almost the same growth condition as cells in complete SFM+TPA on the third day of culture. Results were discussed in the paper.展开更多
Although seemingly disparate,high-energy nuclear physics(HENP)and machine learning(ML)have begun to merge in the last few years,yielding interesting results.It is worthy to raise the profile of utilizing this novel mi...Although seemingly disparate,high-energy nuclear physics(HENP)and machine learning(ML)have begun to merge in the last few years,yielding interesting results.It is worthy to raise the profile of utilizing this novel mindset from ML in HENP,to help interested readers see the breadth of activities around this intersection.The aim of this mini-review is to inform the community of the current status and present an overview of the application of ML to HENP.From different aspects and using examples,we examine how scientific questions involving HENP can be answered using ML.展开更多
Based on the effective medium approximation theory of composites, the whitecap-covered sea surface is treated as a medium layer of dense seawater droplets and air. Two electromagnetic scattering models of randomly rou...Based on the effective medium approximation theory of composites, the whitecap-covered sea surface is treated as a medium layer of dense seawater droplets and air. Two electromagnetic scattering models of randomly rough surface are applied to the investigation of microwave backscattering of breaking waves driven by strong wind. The shapes of seawater droplets are considered by calculating the effective dielectric constant of the whitecap layer. The responses of seawater droplets shapes, such as sphere and ellipsoid, to the backscattering coefficient are discussed. Numerical results of the models are in good agreement with the experimental measurements of horizontally and vertically polarized backscattering at microwave frequency 13.9GHz and different incidence angles.展开更多
This paper reports that terahertz time-domain spectroscopy is used to measure the optical properties of CuS nanoparticles in composite samples. The complex conductivity of pure CuS nanoparticles is extracted by applyi...This paper reports that terahertz time-domain spectroscopy is used to measure the optical properties of CuS nanoparticles in composite samples. The complex conductivity of pure CuS nanoparticles is extracted by applying the Bruggeman effective medium theory. The experimental data are consistent with the Drude-Smith model of conductivity in the range of 0.2 1.5 THz. The results demonstrate that carriers become localized with a backscattering behaviour in small-size nanostructures. In addition, the time constant for the carrier scattering is obtained and is only 64.3 fs due to increased electron interaction with interfaces and grain boundaries.展开更多
Using the concept of optical transformation, we report on an amplifying device, which can make an arbitrary object enlarged. Its potential application to small object identification and detection is foreseeable. The c...Using the concept of optical transformation, we report on an amplifying device, which can make an arbitrary object enlarged. Its potential application to small object identification and detection is foreseeable. The cylindrical anisotropic amplifying shell could be mimicked by radially symmetrical "sectors" alternating in composition between two profiles of isotropic dielectrics; the permittivity and permeability in each "sector" can be properly determined by the effective medium theory. Both the magnetic and nonmagnetic amplifying devices are validated by full-wave finite element simulations. Good amplifying performance is observed.展开更多
Arbitrarily shaped electromagnetic transparent devices with homogeneous, non-negative, anisotropic and generic constitutive parameters are proposed based on linear transformation optics, which provides the flexibility...Arbitrarily shaped electromagnetic transparent devices with homogeneous, non-negative, anisotropic and generic constitutive parameters are proposed based on linear transformation optics, which provides the flexibility for device design that is applicable for the practical fabrication. To remove the anisotropic property, a layered structure is developed based on effective medium theory. Simulation results show that with sufficient layers, the performance of the layered transparent device is nearly as perfect as an ideal device, and it is able to protect an antenna without sacrificing its performance. The feasibility of designing a transparent device by using natural isotropic materials instead of metamaterials would dramatically reduce the difficulty of fabrication and further promote the practicality of the device.展开更多
The expanded graphite (EG) with a low density and better extinction performance can be used in military as passive jamming material in IR and MMW bands. Its complex refractive index is a significant parameter for the ...The expanded graphite (EG) with a low density and better extinction performance can be used in military as passive jamming material in IR and MMW bands. Its complex refractive index is a significant parameter for the extinction property. This paper presents a method to calculate the complex refractive index of EG. The reflection spectra of EG pellets were measured in the 0.24-2.6μm and 2.5-25μm bands, respectively. Based on the measurement results, the complex refractive index of EG in 5-10μm band was calculated by using Kramers-Kronig(K-K) relation and Bruggeman effective medium theory, and then the errors were analyzed. The results indicate that it is feasible to calculate the complex refractive index of EG based on its IR reflection spectra data.展开更多
Kerr effects of two-dimensional (2D) Bismuth iron garnet (BIG)/Ag photonic crystals (PCs) combined magnetic and plasmonic functionalities is investigated with the effective medium theory. An analytical expressio...Kerr effects of two-dimensional (2D) Bismuth iron garnet (BIG)/Ag photonic crystals (PCs) combined magnetic and plasmonic functionalities is investigated with the effective medium theory. An analytical expression of Kerr rotation angles is derived, in which the effects of the surface pasmons polaritons (SPP) on magneto--optical (MO) activities are reflected. The largest enhancement of Kerr rotation up to now is demonstrated, which is improved three orders of magnitude compared with that of BIG film. When λ 〈 750 nm all of the reflection are over 10% for the arbitrary filling ratio fl, in addition, the enhancement of Kerr rotation angles are at least one order of magnitude.展开更多
基金the Major Program of National Natural Science Foundation of China(No.41941019)Shaanxi Province Innovative Talent Promotion Plan-Science and Technology Innovation Team(No.2021TD-55)Central University Natural Science Innovation Team(No.300102262402)。
文摘Combined bodies of rock-like material and rock are widely encountered in geotechnical engineering,such as tunnels and mines.The existing theoretical models describing the stress-strain relationship of a combined body lack a binary feature.Based on effective medium theory,this paper presents the governing equation of the“elastic modulus”for combined and single bodies under triaxial compressive tests.A binary effective medium model is then established.Based on the compressive experiment of concretegranite combined bodies,the feasibility of determining the stress threshold based on crack axial strain is discussed,and the model is verified.The model is further extended to coal-rock combined bodies of more diverse types,and the variation laws of the compressive mechanical parameters are then discussed.The results show that the fitting accuracy of the model with the experimental curves of the concretegranite combined bodies and various types of coal-rock combined bodies are over 95%.The crack axial strain method can replace the crack volumetric strain method,which clarifies the physical meanings of the model parameters.The variation laws of matrix parameters and crack parameters are discussed in depth and are expected to be more widely used in geotechnical engineering.
基金the financial support from the National Natural Science Foundation of China (No. 51274230)the Natural Science Foundation of Shandong Province (No. ZR2012EEL01)the Fundamental Research Funds for the Central Universities (No. 14CX02040A and No. 14CX06023A)
文摘A calculation model based on effective medium theory has been developed for predicting elastic properties of dry carbonates with complex pore structures by integrating the Kuster-Toksǒz model with a differential method.All types of pores are simultaneously introduced to the composite during the differential iteration process according to the ratio of their volume fractions.Based on this model,the effects of pore structures on predicted pore-pressure in carbonates were analyzed.Calculation results indicate that cracks with low pore aspect ratios lead to pore-pressure overestimation which results in lost circulation and reservoir damage.However,moldic pores and vugs with high pore aspect ratios lead to pore-pressure underestimation which results in well kick and even blowout.The pore-pressure deviation due to cracks and moldic pores increases with an increase in porosity.For carbonates with complex pore structures,adopting conventional pore-pressure prediction methods and casing program designs will expose the well drilling engineering to high uncertainties.Velocity prediction models considering the influence of pore structure need to be built to improve the reliability and accuracy of pore-pressure prediction in carbonates.
基金Project supported by Science Foundation of the Chongqing Committee of Education,China (Grant No KJ071205)
文摘A novel optimal design of sub-wavelength metal rectangular gratings for the polarizing beam splitter (PBS) is proposed. The method is based on effective medium theory and the method of designing single layer antireflection coating. The polarization performance of PBS is discussed by rigorous couple-wave analysis (RCWA) method at a wavelength of 1550 nm. The result shows that sub-wavelength metal rectangular grating is characterized by a high reflectivity, like metal films for TE polarization, and high transmissivity, like dielectric films for TM polarization. The optimal design accords well with the results simulated by RCWA method.
文摘We build the perturbation expansion method for nonlinear composite media and extend the EMA for nonlinear effective conductivity. Using the solutions of boundary-value problems of a cylindrical in- clusion, we derive formulae for nonlinear effective conductivity.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 61107053,61138001,and 61007034)the Tianjin Natural Science Foundation,China (Grant No. 11JCYBJC25900)
文摘In this study, we illustrate the effective medium theories in the designs of three-dimensional composite metama- terials of both negative permittivity and negative permeability. The proposed metamaterial consists of random coated spheres with sizes smaller compared to the wavelength embedded in a dielectric host. Simple design rules and formulas following the effective medium models are numerically and analytically presented. We demonstrate that the revised Maxwell-Garnett effective medium theory enables us to design three-dimensional composite metamaterials through the assembly of coated spheres which are random and much smaller than the wavelength of the light. The proposed ap- proach allows for the precise control of the permittivity and the permeability and guides a facile, flexible, and versatile way for the fabrication of composite metamaterials.
基金supported by the Natural Science Foundation of Shandong Province(No.ZR2019BF013)the National Natural Science Foundation of China(Nos.62005095 and 61905091)。
文摘An ultrathin angle-insensitive color filter enabling high color saturation and a wide color gamut is proposed by relying on magnesium hydride-hydrogenated amorphous silicon[MgH2-a-Si:H]lossy dielectric layer.Based on effective medium theory,the MgH2-a-Si:H layer with an ultrathin thickness can be equivalent to a quasi-homogeneous dielectric layer wit an effective complex refractive index,which can be tuned by altering the thickness of MgH2to obtain the targeted value o the imaginary part,corresponding to the realization of high color saturation.It is verified that the proposed color filte offers highly enhanced color saturation in conjunction with a wide color gamut by introducing a few-nanometer thic MgH2layer.As the MgH2-a-Si:H layer retains the advantages of high refractive index and tiny thickness,the proposed colo filter exhibits large angular tolerance up to±60°.In addition,MgH2with an unstable property can interconvert with Mg unde a dehydrogenation/hydrogenation reaction,which empowers the proposed color filter with dynamically tunable outpu color.The proposed scheme shows great promise in color printing and ultracompact display devices with high color sat uration,wide gamut,large angular tolerance,and dynamic tunability.
基金This work was supported by the National Natural Science Foundation of China (Nos. 51236004 and 51321002).
文摘Ultrathin planar absorbers hold promise in solar energy systems because they can reduce the material, fabrication, and system cost. Here, we present a general strategy of effective medium design to realize ultrathin planar broadband absorbers. The absorber consists of two ultrathin absorbing dielectrics to design an effective absorbing medium, a transparent layer, and metallic substrate. Compared with previous studies, this strategy provides another dimension of freedom to enhance optical absorption; therefore, destructive interference can be realized over a broad spectrum. To demonstrate the power and simplicity of this strategy, we both experimentally and theoretically characterized an absorber with 5-nm-thick Ge, 10-nm-thick Ti, and 50-nm-thick SiO2 films coated on an Ag substrate fabricated using simple deposition methods. Absorptivity higher than 80% was achieved in 15-nm-thick (1/50 of the center wavelength) Ge and Ti films from 400 nm to near 1 btm. As an application example, we experimentally demonstrated that the absorber exhibited a normal solar absorptivity of 0.8 with a normal emittance of 0.1 at 500 ~C, thus demonstrating its potential in solar thermal systems. The effective medium design strategy is general and allows material versatility, suggesting possible applications in real-time optical manipulation using dynamic materials.
基金supported by the National Natural Science Foundation of China(Nos.11874311 and 11504306)the Fujian Provincial Natural Science Foundation(No.2017J05015)
文摘Effective medium theory is a powerful tool to solve various problems for achieving multifarious functionalities and applications. In this article, we present a concise empirical formula about effective permittivity of checkboard structures for different directions. To verify our empirical formula, we perform simulations of checkboard periodic structures in squares, rectangles, and sectors in two dimensions. Our results show that the formula is valid in a large range of parameters. This work provides a new way to understand and design composite materials, which might lead to further optical applications in transformation optics.
文摘This paper deals with the magnetohydrodynamic (MHD) flow of an Oldroyd 8-constant fluid in a porous medium when no-slip condition is no longer valid. Modified Darcy's law is used in the flow modelling. The non-linear differential equation with non-linear boundary conditions is solved numerically using finite difference scheme in combination with an iterative technique. Numerical results are obtained for the Couette, Poiseuille and generalized Couette flows. The effects of slip parameters on the velocity profile are discussed.
文摘We investigate a hybrid optomechanical system consisting of two coupled cavities, one of them is composed of two-end fixed mirrors (called the traditional cavity), and the other has a one-end oscillating mirror (named as the optomechanical cavity). A Kerr medium is inside the traditional cavity to enhance the nonlinearity due to the fact that it can cause observing of bistable behavior in intracavity intensity for the optomechanical cavity. The Hamiltonian of the system is written in a rotating frame and its dynamics is described by quantum Langevin equations of motion. Our proposed system exhibits unconventional plots for the mean photon number of the optomechanical cavity which are not observed in previous works. The present results show a deep effect of the Kerr medium on optical bistability of intracavity intensity for the optomechanical cavity. Also, coupling strength of the cavities can effectively change the stability of the system.
基金Supported by the National Natural Science Foundation of China under Grant No 51305080
文摘The effect of the solid matrix and porosity of the porous medium are first introduced to the study of power-law nanofluids, and the Marangoni boundary layer flow with heat generation is investigated. Two cases of solid matrix of porous medium including glass balls and aluminum foam are considered. The governing partial differential equations are simplified by dimensionless variables and similarity transformations, and are solved numerically by using a shooting method with the fourth-fifth-order Runge-Kutta integration technique. It is indicated that the increase of the porosity leads to the enhancement of heat transfer in the surface of the Marangoni boundary layer flow.
文摘The effect of TPA, a potent tumor promoter, on SSV-NIH3T3 cells in serum-free medium was investigated. TPA stimulated DNA synthesis of SSV-NIH3T3 cells on the third day of culture in SFM. In SDS-PAGF of medium conditioned by TPA-treated SSV-NIH3T3 cells (in SFM+TPA), the amounts of four proteins of 31.0 Kd, 28.5 Kd, 25.5 Kd and 13.5 Kd strikingly increased over that of non-TPA-treated counterpart (in SFM). The PDGF-like activity was also detected in CM of SFM+TPA. When insulin and EGF were drown off the SFM+TPA (SFM-Ins-EGF+TPA), TPA lost its ability to stimulate DNA synthesis of SSV-NIH3T3 cells on the third day and SDS-PAGE of the conditioned medium showed that the amounts of the four proteins noted above grately reduced. However, cells in SFM-Ins-EGF+TPA were in almost the same growth condition as cells in complete SFM+TPA on the third day of culture. Results were discussed in the paper.
基金supported in part by the National Natural Science Foundation of China under contract Nos.11890714,12147101(Ma),12075098(Pang),12247107,12075007(Song)the Germany BMBF under the ErUM-Data project(Zhou)the Guangdong Major Project of Basic and Applied Basic Research No.2020B0301030008(Ma).
文摘Although seemingly disparate,high-energy nuclear physics(HENP)and machine learning(ML)have begun to merge in the last few years,yielding interesting results.It is worthy to raise the profile of utilizing this novel mindset from ML in HENP,to help interested readers see the breadth of activities around this intersection.The aim of this mini-review is to inform the community of the current status and present an overview of the application of ML to HENP.From different aspects and using examples,we examine how scientific questions involving HENP can be answered using ML.
基金Project supported by the National Natural Science Foundation of China (Grant Nos 40476062 and 10374026).
文摘Based on the effective medium approximation theory of composites, the whitecap-covered sea surface is treated as a medium layer of dense seawater droplets and air. Two electromagnetic scattering models of randomly rough surface are applied to the investigation of microwave backscattering of breaking waves driven by strong wind. The shapes of seawater droplets are considered by calculating the effective dielectric constant of the whitecap layer. The responses of seawater droplets shapes, such as sphere and ellipsoid, to the backscattering coefficient are discussed. Numerical results of the models are in good agreement with the experimental measurements of horizontally and vertically polarized backscattering at microwave frequency 13.9GHz and different incidence angles.
基金Project supported by the Research Foundation of the State Ethnic Affairs Commission of People’s Repulic of China (Grant No. 09ZY012)the National Natural Science Foundation of China (Grant No. 10904176)+1 种基金the "Project 985"the "Project 211" of Minzu University of China
文摘This paper reports that terahertz time-domain spectroscopy is used to measure the optical properties of CuS nanoparticles in composite samples. The complex conductivity of pure CuS nanoparticles is extracted by applying the Bruggeman effective medium theory. The experimental data are consistent with the Drude-Smith model of conductivity in the range of 0.2 1.5 THz. The results demonstrate that carriers become localized with a backscattering behaviour in small-size nanostructures. In addition, the time constant for the carrier scattering is obtained and is only 64.3 fs due to increased electron interaction with interfaces and grain boundaries.
基金Project supported by the Open Research Program in State Key Laboratory of Millimeter Waves,China (Grant No.K200802)the National Natural Science Foundation of China (Grant No.61302048)the Priority Academic Program Development of Jiangsu Provincial Higher Education Institutions,China
文摘Using the concept of optical transformation, we report on an amplifying device, which can make an arbitrary object enlarged. Its potential application to small object identification and detection is foreseeable. The cylindrical anisotropic amplifying shell could be mimicked by radially symmetrical "sectors" alternating in composition between two profiles of isotropic dielectrics; the permittivity and permeability in each "sector" can be properly determined by the effective medium theory. Both the magnetic and nonmagnetic amplifying devices are validated by full-wave finite element simulations. Good amplifying performance is observed.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61461052 and 11564044)the Key Program of the Natural Science Foundation of Yunnan Province,China(Grant Nos.2013FA006 and 2015FA015)
文摘Arbitrarily shaped electromagnetic transparent devices with homogeneous, non-negative, anisotropic and generic constitutive parameters are proposed based on linear transformation optics, which provides the flexibility for device design that is applicable for the practical fabrication. To remove the anisotropic property, a layered structure is developed based on effective medium theory. Simulation results show that with sufficient layers, the performance of the layered transparent device is nearly as perfect as an ideal device, and it is able to protect an antenna without sacrificing its performance. The feasibility of designing a transparent device by using natural isotropic materials instead of metamaterials would dramatically reduce the difficulty of fabrication and further promote the practicality of the device.
文摘The expanded graphite (EG) with a low density and better extinction performance can be used in military as passive jamming material in IR and MMW bands. Its complex refractive index is a significant parameter for the extinction property. This paper presents a method to calculate the complex refractive index of EG. The reflection spectra of EG pellets were measured in the 0.24-2.6μm and 2.5-25μm bands, respectively. Based on the measurement results, the complex refractive index of EG in 5-10μm band was calculated by using Kramers-Kronig(K-K) relation and Bruggeman effective medium theory, and then the errors were analyzed. The results indicate that it is feasible to calculate the complex refractive index of EG based on its IR reflection spectra data.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11104050,10947168,11204056,and 11304068)
文摘Kerr effects of two-dimensional (2D) Bismuth iron garnet (BIG)/Ag photonic crystals (PCs) combined magnetic and plasmonic functionalities is investigated with the effective medium theory. An analytical expression of Kerr rotation angles is derived, in which the effects of the surface pasmons polaritons (SPP) on magneto--optical (MO) activities are reflected. The largest enhancement of Kerr rotation up to now is demonstrated, which is improved three orders of magnitude compared with that of BIG film. When λ 〈 750 nm all of the reflection are over 10% for the arbitrary filling ratio fl, in addition, the enhancement of Kerr rotation angles are at least one order of magnitude.