Super-resolution focusing of time reversal electromagnetic waves in metal wire array medium
Shielding effectiveness of an apertured rectangular cavity against the near-field electromagnetic waves
Simulation of electromagnetic soliton radiography under laser-produced proton beam
Scattering of the Laguerre-Gaussian beam by a homogeneous spheroid
Phase sensitive spectral domain optical coherence tomography for latent fingerprint detection
An ameliorated fast phase retrieval iterative algorithm based on the angular spectrum theory
Wigner function of N00N state and quantum interference with N00N state as input
Spin coherent-state transformation and analytical solutions of ground-state based on variational-method for spin-Bose models
The modeling of end pumping Yb3+:YVO4 quasi-three-level laser
Fabrication of cylindrical opals and inverse opals and their optical properties
Design of an evanescent-coupled GeSi electro-absorption modulator based on Franz-Keldysh effect
A combined scheme of polarization mode dispersion compensation and polarization de-multiplexing in a polarization division multiplexing system with direct detection
Nonlinear forced oscillations of gaseous bubbles in elastic microtubules
Effect of wall friction on subharmonic bifurcations of impact in vertically vibrated granular beds
Granular materials consist of a large number of discrete solid particles. When subjected to external vibrations, they exhibit various intricate dynamical behaviors, Which usually depend in a complicated way on many physical factors, such as air dragging, friction from the container wall and so forth. In this work, vertical vibrations are applied to a bed of stainless-steel spheres contained in a glass tube, and the subharmonic bifurcations of impact of particles on the container bottom are investigated. To eliminate the effects of air dragging, we evacuate the container or perforate the container bottom to make it quite permeable to the air. Experiments performed in such containers reveal that the impact bifurcations are controlled solely by the normalized vibration acceleration, but independent of the particle size, the filling height of particles, and the frequency of forced vibration. The sliding friction from the container wall is treated as a constant one with the direction opposite to the velocity relative to the container wall. By involving this damping term into the completely inelastic bouncing ball model, an explanation for the experimental results is made. Simulations on the averaged experimental bifurcation points indicate that the magnitude of wall friction is about 10% of the total weight of the particles.
Numerical investigation on the characteristics of the mushroom-like vortex structure generated by a submerged laminar round jet
The motion and acoustic radiation characteristics for cavitation in the compressible vortex fluid
A 3D numerical simulation to study thesystem of gyrotron
In order to break the limitation of gyrotron emission producing the ideal electron beam in the traditional gyrotron numerical simulation, this paper on the basis of theoretical analysis of structural parameters for the 94 GHz double-anode magnetron injection electron gun, by optimizing the grid plot of conformal FDTD algorithm, obtains the high-performance electron beam of the horizontal and vertical velocity ratio of 1.42 and the maximum velocity spread of 5.92%, By using the optimized electron gun to replace the traditional gy rotron emission in the numerical simulation of the gyrotron system and using the four-process parallel MPI in computation, we finally obtain a TE03 mode, 94 GHz, the average output power of about 40 kW, with on efficiency of 10.5% for the high-performance gyrotron oscillating tube.
A non-linear analysis for gamma-ray spectrum based on compressed sensing
Numerical simulation of Trichel pulse characteristics in bar-plate DC negative corona discharge
An improved multi-component two-dimensional hybrid model is presented for the simulation of Trichel pulse corona discharge. The model is based on the plasma hydrodynamics and chemical models, including 12 species and 27 reactions. In addition, the photoionization and secondary electron emission effects are taken into account. Simulation is carried out on a bar-plate electrode configuration with an inter-electrode gap of 3.3 mm, the positive potential applied to the bar being 5.0 kV, the pressure in air discharge being fixed at 1.0 atm, and the gas temperature assumed to be a constant (300 K). In this paper, some key microscopic characteristics such as electric field distribution, net charge density distribution, electron density distribution at 5 different instants during a Trichel pulse are analyzed emphatically. Further more, the electron generation and disappearing rates, positive and negative ion distribution characteristics along the axis of symmetry are also investigated in detail in the later Trichel pulse cycle. The results can give valuable insights into the physical mechanism of negative corona discharge.
Influence of addifion of electronegative gases on the properties of capacitively coupled Ar plasmas
Simulation of hollow cathode discharge by combining the fluid model with a transport model for metastable Ar atoms
Iterative method for multimode waveguide design
Effects of low-temperature annealing phosphorous gettering process on the electrical properties of multi-crystalline silicon with a low minority carrier lifetime
A new low-temperature annealing phosphorous gettering process (LTAPGP) was developed to improve the electrical properties of multi-crystalline silicon which has a low minority carrier lifetime. LTAPGP combined a multi-plateau temperature phosphorous gettering process and a low-temperature annealing process. LTAPGP can remove the iron impurities and crystallographic defects of multi-crystalline silicon, and improve the electrical properties of silicon solar cells that were produced from low minority carrier lifetime silicon wafers. Compared with multi-plateau and two-plateau temperature phosphorous gettering process, LTAPGP was more effective in gettering iron impurities and repairing crystallographic defects. The multi-crystalline silicon wafers with a low minority carrier lifetime went through an LTAPGP process were utilized to produce solar cells. The IV-measurement data prove that the efficiency of the new solar cells is 0.2% higher than that of specimens subject to the multi-plateau and two-plateau temperature processes. The results indicat that LTAPGP can make the low minority carrier lifetime silicon wafers to be used in solar cell industry, improve the utilization ratio and reduce the production cost of cast polysilicon.
A type of the new exact and approximate conserved quantity deduced from Mei symmetry for a weakly nonholonomic system
Solution of the transfer models of femtosecond pulse laser for nano metal film
Static and dynamic analysis of elastic shell structures with smoothed particle method
A molecular dynamics simulation on the relationship between contact angle and solid-liquid interfacial thermal resistance
Optical lattice solitons in nonlinear media under the condition of hollow cylinder boundary
Dynamical entanglement in the model of field interacted with atoms of a nonlinear medium
Off-diagonal Berry phase in nonlinear systems
Thermal quantum discord in Heisenberg XXZ model under different magnetic field conditions
Ultracold spin-1 atoms in three-well optical superlattice under a weak magnetic field
Nonliner Landau-Zener tunneling of a Bose-Fermi mixture
Soliton dynamical behavior of the condensates trapped in a square-well potential
Effect of non-Gaussian noise on negative mobliity
Equivalent modeling and bifurcation analysis of V2 controlled buck converter
Study on nonlinear phenomena in single phase H bridge inverter based on the periodic spread spectrum
Dynamics of rumor spreading in mobile social networks
Delay time obtaining method using the maximum joint entroy on the basis of symbolic analysis
In this paper, the local maximum of joint entroy was computed using the symbolic analysis method so as to determine the appropriate delay time of the phase space reconstruction. The numerical experiments for three typical chaotic systems show that the present method could reduce computation, increase the efficiency, and also could obtain the optimum delay time accurately and rapidly. And it could reconstruct the original phase space from the time series effectively. Thus it provides a fast and effective way to identify the chaotic signal.
Limited penetrable visibility graph from two-phase flow for investigating flow pattern dynamics
Hardware implementation for blind demodulation method for chaotic direct sequence spreadspectrum signals
Time-controllable projective synchronization of a class of chaotic systems based on adaptive method
To solve the problem of indeterminate synchronization time in different chaotic systems, this paper presents a time-controllable synchronization scheme. A general synchronization controller and parameter update laws are proposed to stabilize the error system, thus the drive and response systems could be synchronized up to a given scaling matrix at a pre-specified exponential convergence rate. The synchronization time formula is strictly deduced, which suggests that the speed of synchronization is determined by several parameters, such as exponential rate, initial system value and other parameters brought in by the controller. By adjusting these parameters, the performance of the synchronization can be effectively improved. In numerical simulation, two nonidentical 3D autonomous chaotic systems are chosen to verify this method. The error system can be rapidly stabilized, and unknown parameters are also identi?ed correctly. Firally, two groups of time-controllable parameters are given to verify the theory, wherein synchronization of both cases can be obtained quickly and each result of the synchronization is consistent with the theoretical calculation. The synchronization scheme is characterized by high safety and efficiency, and has its potential value in secure communication.
Complicated behaviors and non-smooth bifurcation of a switching system with piecewise linearchaotic circuit
Joint compression and tree structure encryption algorithm based on EZW
The numerical-aperture-dependent optical contrast and thickness determination of ultrathin flakes of two-dimensional atomic crystals: A case of graphene multilayers
Numerical simulation of electrode potential influence on the performance of ionization gauge with carbon nanotubes cathode
Theoretical studies of electrodes potential influence on the sensitivity and ratio of anode current and emission current (Igrid/Ie) will be beneficial for providing theoretical basis and experimental instruction in the research of ionization gauge with carbon nanotubes cathode. In this paper, based on the structure of IE514 extractor gauge, the model of carbon nanotube ionization gauge is built by ion optic simulation software SIMION 8.0. And the influence of electrode potential on the sensitivity and Igrid/Ie is discussed. Results show that with increasing ratio between anode voltage and gate voltage (Vgrid/Vgate), Igrid/Ie increases, while the sensitivity of the gauge decreases with the increase in anode voltage, which would further affect the extension of vacuum measurement lower limit. Moreover, the simulation results are in good agreement with the experimental data reported. Consequently, it is very important to improve the sensitivity, anode current and extension of measurement lower limit to set up an appropriate electrode voltage. In addition, the method adopted in this paper can be extended to the research and development of new-styles of extremely high vacuum ionization gauge of carbon nanotube cathode, which could provide an effective method to resolve the problem of extremely high vacuum measurement.
Spectroscopic properties of AlC (X4∑-, B4∑-) molecule
Potential energy function and spectroscopic parameters of SN- molecular ion
Study on spectroscopic properties and molecular constants of the ground and excited states of AsCl free-radical
The dissociation limit of AsCl free-radical is correctly determined based on group theory and atomic and molecular statics. Potential energy curves (PECs) for the ground state and several low-lying electronic excited states of AsCl free-radical are calculated using the multi-reference configuration interaction method with the basis set of aug-cc-pV5Z where the Davidson correction is considered as an approximation to full CI. Separation parameters (Re, ωe, ωeχe, D0, De, Be and αe) are evaluated using the PEC of AsCl. Spectroscopic parameters are compared with those reported in the literature, and excellent agreement is found between them. With the PEC of AsCl free-radical, forty vibrational states of AsCl free-radical are predicted when J=0 by numerically solving the radial Schrödinger equation of nuclear notion. For each vibrational state, the vibrational levels and inertial rotation constants are reported.
Investigation of photoionization of excited atom irradiated by the high-frequency intense laser
Research on SRAM functional failure mode induced by total ionizing dose irradiation
First-principles study on elastic properties of hexagonal phase ErAx (A=H, He)
Experimental diagnostic of melting fragments under explosive loading
Experimental study of friction effect under impact loading
Effect of thickness on the properties of Cu(Inx,Ga1-x)Se2 back conduct Mo thin films prepared by DC sputtering
Effects of parameter modifications on phase transition properties of ferroelectric thin films
The site preference of refractory element W in NiAl dislocation core and its effects on bond characters
The first-principles study on properties of B-doped at interstitial site of Cu∑5 grain boundary
Study on proton irradiation induced defects in GaN thick film
A first-principle study on the interfacial properties of Cu/CeO2(110)
Low-temperature growth of AlN thin films by plasma-enhanced atomic layer deposition
Effect of co-implantation of nitrogen and fluorine on the fixed positive charge density of the buried oxide layer in SIMOX SOI materials
The spectrum-control of dual-wavelength LED with quantum dots planted in quantum wells
Ultralow-voltage in-plane-gate indium-tin-oxide thin-film transistors made of P-doped SiO2 dielectrics
First-principles calculation of preferential site occupation of Dy ions in Nd2Fe14B lattice and its effect on local magnetic moments of Fe ions
Calculation and analysis of surface acoustic wave properties of ZnO film on diamond under different excitation conditions
Resonant frequency temperature stability of CaTiO3 based microwave dielectric ceramics
Effects of sefl-reduction of glass matrix on the broadband near infrared emissions from Bi-doped alkali earth aluminoborosilicate glasses
Study on the photoluminescence properties of InN films
Spectroscopic properties and energy transfer of Ce3+/Eu2+ codoped oxide glasses with high Gd2O3 concentration
Effects of annealing temperature on the microstructure and p-type conduction of B-doped nanocrystalline diamond films
Phase field crystal simulation of microscopic deformation mechanism of reverse Hall-Petch effect in nanocrystalline materials
The nanocrystalline (NC) materials of several average grain sizes ranging from 11.61 to 31.32 nm were obtained by using the phase field crystal model (PFC), and the microscopic deformation mechanism of strengthening law for the uniaxial tensile deformation was discussed. Simulated results show that grain rotation and grain boundary (GB) migration are mainly responsible for the microscopic deformation. Since small grain size is favorable for grain rotation so that it can make the yield strength reduced; and the NC materials would show a reverse Hall-Petch effect. When the grain size is so small and the strain exceeds the yield point to about 4%, dislocation activities begin to occur. Mainly by the change of GB structure (disorganizing triple grain boundary junction and then promoting grain migration), the GB can play a finite contribution to deformation. With increasing grain size, grain rotation becomes difficult, and the grain serration and emission of dislocations are observed.
Influence of applied magnetic field on properties of silicon nitride thin film with light trapping structure prepared by R.F. magnetron sputtering
In the applied magnetic field different magnetic intensities in the permanent magnet were introduced between the substrate and target, so as to study their influence on the properties of silicon thin films with light trapping structure prepared by R.F. magnetron sputtering. The microstructures, surface morphology and optical properties of the films were characterized by X-ray diffraction, atomic force microscope (AFM) and ultraviolet spectrophotometer separately. Results show that the silicon nitride thin films are still in amorphous state although an magnetic field was applied on them; however, when the magnetic field in the center is of 1.5 T, the surface morphology of the films has dramatically changed to a special peak structure, i.e. pyramid-like protuberances which are perpendicular to the basal surface; meanwhile, in the visible and near infrared range, the average transmittance of the sample is the highest, which is more than 90%, nearly twice as much as the transmittance of the sample without applied magnetic field, thus the light trapping effect is the great.
Electrical, optical properties and structure characterization of In-doped copper nitride thin film
Thin films of ternary compounds CuxInyN were grown on Si (100) wafers by RF magnetron cosputtering at a low temperature, low power and pure N2 environment. The effect of In incorporation on the structure and physical properties of copper nitride was obvious, which was evaluated by characterizing the film chemical bonding state, structure, electrical and optical properties. In XPS, shift of binding energy, Auger peak and Auger chemical parameters all reflected the chemical changes in the environment. For samples with In content below 8.2 at.%, either the BE increasing of Cu 2p3/2 and In 3d5/2 or the decreasing of N1s could mainly contribute to the Cu-In-N bond formation. For the Cux InyN sample with 4.6% In, indium atoms were consistently confirmed to be incorporated into the body center of Cu3N anti-ReO3 structure as shown by XRD and TEM. The strong (001) preferred orientation of copper nitride crystalline phase was kept predominant in the films until the In content goes up to 10.8 at.%, the texture changed to (111) orientation. The R-T curves of CuxInyN films changed from typical exponential to linear with increasing In. Near constant electrical resistivity in a large temperature range with small TCR of -6/10000 was investigated in the CuxInyN sample with 47.9 at.% In. Moreover, the optical band gap, due to Burstein-Moss effect, was investigated to enhance from 1.02 to 2.51 eV with the In content increasing from 0% to 26.53%, accompanied with band-gap transition from direct to indirect.
Effects of system size on population behavior
A dynamic light scattering study of counter-ions condensation on DNA
MCG source reconstruction based on greedy sparse method
Construction and analysis of complex brain functional network under acupoint magnetic stimulation
Unbiased solid surface charging research inplasma environment
An analog modulated simulation source for X-ray pulsar-based navigation