Light scattering by small particles has a long and interesting history in physics.Nonetheless,it continues to surprise with new insights and applications.This includes new discoveries,such as novel plasmonic effects,a...Light scattering by small particles has a long and interesting history in physics.Nonetheless,it continues to surprise with new insights and applications.This includes new discoveries,such as novel plasmonic effects,as well as exciting theoretical and experimental developments such as optical trapping,anomalous light scattering,optical tweezers,nanospasers,and novel aspects and realizations of Fano resonances.These have led to important new applications,including several ones in the biomedical area and in sensing techniques at the single-molecule level.There are additionally many potential future applications in optical devices and solar energy technologies.Here we review the fundamental aspects of light scattering by small spherical particles,emphasizing the phenomenological treatments and new developments in this field.展开更多
The complex refractive index of small ash particles is determined from the transmittance spectrum of dilute particle suspensions obtained from experiment and by the application of the precise Mie scattering theory and...The complex refractive index of small ash particles is determined from the transmittance spectrum of dilute particle suspensions obtained from experiment and by the application of the precise Mie scattering theory and dielectric dispersion Kramers-Kroning relations. The numerical simulation results for the ash particles with data given in literature [1] show that with this method the accuracy is improved and the applicable range of the wavelength and the particle size is expanded.At last the transmittance spectrum of the ash particle cloud from Tic Fa Coal Mine was measured by an infrared spectrometer and its complex refractive index is determined.展开更多
Theoretical and experimental results show that the state of minimum Ginsburg Landau free energy of small superconducting particles contains no flux line if the applied field is smaller than its critical field. For suc...Theoretical and experimental results show that the state of minimum Ginsburg Landau free energy of small superconducting particles contains no flux line if the applied field is smaller than its critical field. For such micron sized particles, after being cooled in a small magnetic field (e.g. less than 100 μT), the moment remaining during subsequent zero field warming contains almost no contribution from trapped flux and is dominated entirely by the paramagnetic Meissner effect (PME) of the particles. A systematic study of such a moment has been carried out to reveal its characteristic behavior of temperature, magnetic field and cooling or warming rate dependence. Methods for removing and recovering the PME of small superconducting particles are also reported.展开更多
A range of powdered Bi:2 212 samples exhibiting the paramagnetic Meissner effect (PME) are systematically examined. Interpretation of the results is made in terms of a phenomenological model in which there is a concen...A range of powdered Bi:2 212 samples exhibiting the paramagnetic Meissner effect (PME) are systematically examined. Interpretation of the results is made in terms of a phenomenological model in which there is a concentration within the material of small local moments that can be polarized during a field cooling. Information about the magnitudes of these local m0oments and their distribution are deduced. Relations between the local moments and the particle sizes, the weak link, oxygen content and the interactions between the local moments are also discussed. Comparison of the results from small particles and bulk samples shows that conclusions obtained from small particle experiments are reliable and universal.展开更多
Demands for new gold deposits are increasing worldwide and the need to better define lode and placer claims is a critical environmental and economic issue. Recently, interesting results have been produced using dedica...Demands for new gold deposits are increasing worldwide and the need to better define lode and placer claims is a critical environmental and economic issue. Recently, interesting results have been produced using dedicated geological information systems designed to explore for earth mineral deposits. These systems employ properties of fundamental physical fields generated by interactions of superlight elementary particles. GV technology （Geo-Vision geological direct detection radiometric and Air-Gamma technology）, a revolutionary technology for exploring the earth from outer space and from inside aircraft, has been utilized to identify and precisely locate gold deposits. All elements of the Earth＇s crust exist in an excited state and are constantly emitting what can be called their ＂intrinsic radiation＂. The melding of science and data interpretation makes GV Technology ideal for defining both lode and placer gold deposits. The use of GV technology will improve success ratios associated with the exploration for and delineation of gold deposits and provide better definition of successful core drilling locations. The technology will also decrease the cost of defining gold deposits and since GV technology is ecologically friendly, it provides considerable reductions in environmental mitigation costs. From 1995 to 2014, GV technology has been used to identify and delineate gold deposits in Russia, Mongolia, Kirghizia, Tanzania, Ethiopia, Namibia, Australia, and the United States.展开更多
We study the behaviors of thermalization in Fermi–Pasta–Ulam–Tsingou(FPUT) system with small number of particles using periodic boundary conditions. The total energy has initially equidistributed among some of the ...We study the behaviors of thermalization in Fermi–Pasta–Ulam–Tsingou(FPUT) system with small number of particles using periodic boundary conditions. The total energy has initially equidistributed among some of the lowest frequency modes. The thermalization time t_(eq) depending on system's energy density ε scales as t_(eq) ∝ε^(-4) only within a certain range of nonlinearity. In this range of nonlinearity, energies can interchange between the initial excited modes and other modes continuously with time until reaching the thermalized state. With a further decreasing nonlinearity, a steeper growth than ε^(-4) will appear. In the very weakly nonlinear regime, energies on low frequency modes are found to be frozen on large time scales. Redistribution of mode energies happens through the resonances of high frequency modes.展开更多
基金Work at ORNL was supported by the United States Department of Energy,Basic Energy Sciences,Materials Sciences and Engineering Division.
文摘Light scattering by small particles has a long and interesting history in physics.Nonetheless,it continues to surprise with new insights and applications.This includes new discoveries,such as novel plasmonic effects,as well as exciting theoretical and experimental developments such as optical trapping,anomalous light scattering,optical tweezers,nanospasers,and novel aspects and realizations of Fano resonances.These have led to important new applications,including several ones in the biomedical area and in sensing techniques at the single-molecule level.There are additionally many potential future applications in optical devices and solar energy technologies.Here we review the fundamental aspects of light scattering by small spherical particles,emphasizing the phenomenological treatments and new developments in this field.
文摘The complex refractive index of small ash particles is determined from the transmittance spectrum of dilute particle suspensions obtained from experiment and by the application of the precise Mie scattering theory and dielectric dispersion Kramers-Kroning relations. The numerical simulation results for the ash particles with data given in literature [1] show that with this method the accuracy is improved and the applicable range of the wavelength and the particle size is expanded.At last the transmittance spectrum of the ash particle cloud from Tic Fa Coal Mine was measured by an infrared spectrometer and its complex refractive index is determined.
文摘Theoretical and experimental results show that the state of minimum Ginsburg Landau free energy of small superconducting particles contains no flux line if the applied field is smaller than its critical field. For such micron sized particles, after being cooled in a small magnetic field (e.g. less than 100 μT), the moment remaining during subsequent zero field warming contains almost no contribution from trapped flux and is dominated entirely by the paramagnetic Meissner effect (PME) of the particles. A systematic study of such a moment has been carried out to reveal its characteristic behavior of temperature, magnetic field and cooling or warming rate dependence. Methods for removing and recovering the PME of small superconducting particles are also reported.
文摘A range of powdered Bi:2 212 samples exhibiting the paramagnetic Meissner effect (PME) are systematically examined. Interpretation of the results is made in terms of a phenomenological model in which there is a concentration within the material of small local moments that can be polarized during a field cooling. Information about the magnitudes of these local m0oments and their distribution are deduced. Relations between the local moments and the particle sizes, the weak link, oxygen content and the interactions between the local moments are also discussed. Comparison of the results from small particles and bulk samples shows that conclusions obtained from small particle experiments are reliable and universal.
文摘Demands for new gold deposits are increasing worldwide and the need to better define lode and placer claims is a critical environmental and economic issue. Recently, interesting results have been produced using dedicated geological information systems designed to explore for earth mineral deposits. These systems employ properties of fundamental physical fields generated by interactions of superlight elementary particles. GV technology （Geo-Vision geological direct detection radiometric and Air-Gamma technology）, a revolutionary technology for exploring the earth from outer space and from inside aircraft, has been utilized to identify and precisely locate gold deposits. All elements of the Earth＇s crust exist in an excited state and are constantly emitting what can be called their ＂intrinsic radiation＂. The melding of science and data interpretation makes GV Technology ideal for defining both lode and placer gold deposits. The use of GV technology will improve success ratios associated with the exploration for and delineation of gold deposits and provide better definition of successful core drilling locations. The technology will also decrease the cost of defining gold deposits and since GV technology is ecologically friendly, it provides considerable reductions in environmental mitigation costs. From 1995 to 2014, GV technology has been used to identify and delineate gold deposits in Russia, Mongolia, Kirghizia, Tanzania, Ethiopia, Namibia, Australia, and the United States.
基金supported by the Fundamental Research Funds for the Central Universities,China (Grant Nos. 2017B17114 and B210202152)。
文摘We study the behaviors of thermalization in Fermi–Pasta–Ulam–Tsingou(FPUT) system with small number of particles using periodic boundary conditions. The total energy has initially equidistributed among some of the lowest frequency modes. The thermalization time t_(eq) depending on system's energy density ε scales as t_(eq) ∝ε^(-4) only within a certain range of nonlinearity. In this range of nonlinearity, energies can interchange between the initial excited modes and other modes continuously with time until reaching the thermalized state. With a further decreasing nonlinearity, a steeper growth than ε^(-4) will appear. In the very weakly nonlinear regime, energies on low frequency modes are found to be frozen on large time scales. Redistribution of mode energies happens through the resonances of high frequency modes.
