ISSN / EISSN : 2161-0916 / 2161-0924
Published by: Hans Publishers (10.12677)
Total articles ≅ 262
Latest articles in this journal
Modern Physics, Volume 12, pp 1-11; https://doi.org/10.12677/mp.2022.121001
Volatile organic compounds (VOC) emissions from porous wood-based panel with fractal structure seriously pollute indoor environment. In this paper, a time-fractional mass transfer model is proposed to analyze the anomalous diffusion of VOC emissions from wood-based panel. The time-fractional convective mass transfer boundary condition and mass balance equation are both developed for the first time. The finite difference scheme and the improved Nelder-Mead simplex search and particle swarm optimization are used to optimize the model numerically. Compared with Deng and Kim’s model, the numerical simulation results of present model are in better agreement with the experimental data, and the relative error Re (0.0034%) is much smaller than that of the previous model (0.0257%). This shows that the present model can reveal better the heavy-tailed phenomenon of VOC releases from wood-based panel more accurately. In addition, the influences of the key release parameters on VOC emission are analyzed. The results indicate that higher α, ε, D, N and lower Kma all can promote VOC emission, which can provide theoretical guidance for improving indoor air quality.
Modern Physics, Volume 12, pp 79-85; https://doi.org/10.12677/mp.2022.123008
The theoretical method for calculating the dynamic polarizability of monovalent atoms by the variationally stable procedure is given. On this basis, the calculation program is independently developed by us. As an application, the dynamic polarizabilities at different frequencies are calculated with hydrogen atoms as an example, by this program. The calculation results are compared with the Green function data in the literature, with good consistency. The convergence of the variationally stable procedure is analyzed, and the corresponding tune-out wavelength is further determined by using the polarizability calculated in the present work.
Modern Physics, Volume 12, pp 86-95; https://doi.org/10.12677/mp.2022.123009
Previous studies have shown that AlFeTiCrZnCu high entropy alloys (HEA) are simple cubic crystal structure. In order to study the influence of element content, this paper adopts the method of first-principles density functional theory ab initio calculation based on plane wave pseudopotential with generalized gradient approximation (GGA). The long-range solid solution structure model of the HEA was established on the single atom of the square structure unit cell by the virtual crystal approximation(VCA), and the density, lattice constant, elastic modulus and formation of the high-entropy alloy AlFeTiCrZnCux with different Cu element contents were calculated. The calculated results indicate that the lattice parameter of HEA AlFeTiCrZnCux decreases with the increasing mole fraction of Cu, and the mass density increases. The mechanical stability and brittleness of HEA AlFeTiCrZnCux were regardless of the content of Cu. The total energy and the heat of formation decrease with the increasing mole fraction of Cu, but the system stability and thermodynamic stability increase.
Modern Physics, Volume 12, pp 50-58; https://doi.org/10.12677/mp.2022.123005
The Michelson interferometer is an important precision optical research instrument that uses the split-amplitude method to obtain coherent double beams to achieve interference. It has been in-vented since 1881 for nearly 140 years. However, in practical applications, there are still some differences in the understanding of the role of individual components, and there are some controversies about the concept of some interference in the light involved. Based on the principle and concept of the most basic light interference, this paper combines Young’s interference, equidistant interference, equal-thickness interference and Michelson’s interference for comparative analysis based on relevant literature data, and gives a reasonable viewpoint in order to calm down the existing disagreements and disputes.
Modern Physics, Volume 12, pp 59-68; https://doi.org/10.12677/mp.2022.123006
The light intensity distribution formed by light waves through gratings is actually the result of single slit (groove) diffraction and multi-slot (groove) interference of grating. It has been observed that after a step with enough stages reflects the incident noise of a certain intensity, the tone of a certain frequency band will be obtained in the reflected sound field. In this paper, the glare grating is regarded as a plane reflection sound grid, that is, the blazed sound grid, which gives the distribution of the sound intensity of the blazed sound grid, and also gives the constraint relationship that the corresponding path difference of the reflected sound waves between adjacent grooves is satisfied. At the same time, according to the field survey data and the corresponding spectral curve combined with the principle of plane reflection acoustic grating, the music phenomenon formed in the multistage step reflection sound field is analyzed, and the firecrackers under the monument of the Susan Anti-Japanese War Memorial in Maoshan, Jiangsu, China. The two phenomena of the “Put the firecrackers in the air under the monument” and “Recruiting crane” in Heshan, Qingdao, Shandong, China are explained as examples.
Modern Physics, Volume 12, pp 12-30; https://doi.org/10.12677/mp.2022.121002
This article assumes that the elementary particle is a spin gradient magnetic pole field formed by the interaction of positive and negative magnetic poles. The galaxy nuclear, stellar nuclear, plane-tary nuclear and their spin gradient magnetic pole field are composed of the corresponding high- energy nuclear particle or nuclear axis particle. Dark matter refers to the galaxy nuclear particle, stellar nuclear particle, planetary nuclear particle and negative magnetic pole. Dark energy refers to the spin forces of the galaxy nuclear, stellar nuclear, planetary nuclear, and the expansion forces of high-density negative magnetic pole field. This article discusses that the gravitational forces, electromagnetic forces, strong forces and weak forces are all produced by the interaction of positive and negative magnetic poles. The binding forces of the positive magnetic poles ring coaxial spin of the nuclear particle is the strong forces, the decay forces of outer layer positive magnetic pole ring of the nuclear particle is the weak forces, the spin forces of the stellar (or planetary) gradient magnetic pole field on the corresponding orbit of the gravitational field is the electromagnetic forces (or kinetic energy), and the cohesive forces of the galaxy nucleus, stellar nucleus, and planetary nucleus to the magnetic pole of the gradient magnetic poles field (gravitational field) is the gravitational forces. This article attempts to discuss the unified phase field theory based on the interaction of positive and negative magnetic poles, and uses the curvature tensor equation of unified phase field to explains the unification of the gravitational force, electromagnetic force, strong force and weak force in the universe, and is verified by the astronomical observation data of the interactions be-tween the solar system and the Milky Way, the interactions between the planets and the solar system, the planetary perihelion precession. The NASA astronomical observation data is completely consistent with the calculated data of the phase field curvature tensor equation. Differential geometric variables are covariant with physical variables. The Lagrangian function of Einstein’s mass-energy equation, the Lagrangian function of the Schrodinger particle differential motion wave function based on the theory of relativity, the Lagrangian density of the Young-Mills gauge field equation, and the planets phase difference momentum-energy tensor of the curvature tensor equation is completely consistent in the interactions between planets and sun. These results prove that the unified phase field theory is in line with the physical reality of the universe.
Modern Physics, Volume 12, pp 69-78; https://doi.org/10.12677/mp.2022.123007
The effect of chain topology on the self-assembly behavior of AB-type block copolymers confined in thin film was studied using the self-consistent field theory method (SCFT). Firstly, the AmB miktoarm star copolymer was designed and the effect of the number of arms m on the stability of per-forated lamella (PL) structure was investigated by constructing the phase diagrams for m = 1, 2 and 4 with the volume fraction (fA) and size of confinement (D). The increasing m is beneficial to expanding the stable phase region of the PL structure, while it increases not very obviously when m > 2. Then fix m = 2 and the ABAT-type block copolymer was designed by regulating the tethering point of one A block on the B block, which is characterized by the parameter τ. The favorable τ for the stability of the PL phase is examined by constructed the phase diagram of fA~D, where the free energy contributions, segment distribution and feature size of the PL structure under different τ are analyzed. It indicates that the degree of freedom of the A block is affected by the tethering point on the B block, and its spatial distribution in the domain affects the stability of the PL structure. This study provides theoretical guidance for the preparation of perforated structures in related experiments.
Modern Physics, Volume 12, pp 97-107; https://doi.org/10.12677/mp.2022.124010
In this paper, a coating research method based on different experimental conditions is proposed, and a broadband antireflection film in visible light band is designed. TiO2 and MgF2 were selected as coating materials. The broadband antireflection film (AR film) in 380 nm~780 nm band was designed by TFCalc software. The refractive index of each band of single-layer TiO2 and MgF2 film, as well as the effects of different central wavelengths, refractive index error and thickness error of single-layer material and incident angle on the average transmittance (AT) of broadband AR film in visible band were analyzed through simulation experiments. The results show that when the central wavelength is 610nm, the incident angle is less than 50˚, the refractive index deviation of TiO2 is −0.2~0, the thickness deviation is −10~0 nm, the refractive index deviation of MgF2 is −0.1~0.1, and the thickness changes between −5 nm~5 nm, the full band average transmittance can be more than 96%, which provides a reference research way for the research of optical films.
Modern Physics, Volume 12, pp 108-114; https://doi.org/10.12677/mp.2022.124011
We analyzed the optical transmission of the optomechanical system, which consists of rotating doublemode cavities and a mechanical resonator. When it is drived by a strong field from the left side or the right side, the probe optical response is considered under the Sagnac effect. For the spectrum of the output field, it shows the nonreciprocal transmission behavior. We expect that this scheme may be applicable in information processing and optical communication in the future.
Modern Physics, Volume 12, pp 129-135; https://doi.org/10.12677/mp.2022.125013
In the famous double-slit interference experiment, there is a problem that a single photon passes through two slits at the same time. In the splitting delay experiment, there is a problem of single-photon path and causality. In this paper, through the analysis of the meaning of single photon in different situations, it is believed that the essence of these problems is the understanding of single photons. A single photon (energy hf) in the traditional sense is f wave packets with energy h. We take a wave packet as a basic unit of light, then we traditionally mean when a photon is emitted, it actually emits f wave packets. We understand a wave packet as a photon, and these troubles do not exist. We compare a single photon in the traditional sense to a drop of water, a wave packet is equivalent to a water molecule, water will be vaporized into water molecules in the air, and a photon in the traditional sense will also be scattered into tiny wave packets in space. We cannot see the running path of molecules in space, and similarly, we cannot determine the running path of the wave packet of light. This paper also predicts the single photon experiment in the traditional sense. When a single photon in the traditional sense is emitted, if the detection energy of the single photon is reduced, the photons can be detected on both paths of the spectroscopic experiment, which can confirm the whether the single photon in the traditional sense is separable and whether it is a real single photon.