Search

In this study, we develop a novel method for determining electron transport coefficients from electron swarm maps measured by a scanning drift-tube experiment. In our method, two types of electron continuity equations that describe either the spatial or the temporal evolution of an electron swarm are discovered in the electron swarm map. The electron transport coefficients can be determined from the coefficients in the discovered equations. Therefore, we can determine the Townsend ionization coefficient, ionization rate coefficient, center-of-mass drift velocity, mean arrival-time drift velocity, longitudinal diffusion coefficient, and longitudinal third-order transport coefficient. These transport coefficients in argon are determined over a wide range of reduced electric fields, E / N, from 29.7 to 1351.6 Td (1 Td = 10−21 Vm2) using our method. We establish that the consideration of high-order transport coefficients, which have been systematically ignored so far, is important for the proper determination of low-order transport coefficients, specifically the electron drift velocity and longitudinal diffusion coefficient, in the presence of ionization growth. [ABSTRACT FROM AUTHOR]

The study investigated the effect of refraining from going out during the coronavirus disease 2019 pandemic on physical function in community-dwelling older adults. The study included 49 patients who underwent home-visit rehabilitation. Four parameters of physical function—grip strength, five-times sit-to-stand test, single-leg stance test, and standing test for imbalance and disequilibrium (SIDE)—were assessed. They were evaluated before (March 2020) and after (May 2020) the state emergency was imposed, and the results were compared. The grip strength decreased significantly. A significant difference was also observed in the proportion of different SIDE levels in the study group before and after the implementation of the state emergency. The number of SIDE 2a or lower patients increased during the state emergency (p < 0.001). Comprehensive community support and rehabilitation are necessary to maintain physical function in older individuals. In particular, we believe that there is a need to utilize remote rehabilitation using digital devices (such as internet-based guidance) so that older adults can continue to exercise at home. [ABSTRACT FROM AUTHOR]

Electron collision cross section set for N2 is proposed. The proposed set consists of vibrational elastic momentum transfer cross section and cross sections for 31 rotational excitation, 29 rotational deexcitation, 10 vibrational excitation, 17 electronic excitation, 2 neutral dissociation, and 5 ionization collision processes. Electron transport coefficients in N2, N2/He, and N2/Ar are calculated by Monte Carlo method with considering anisotropic inelastic electron scattering and partitioning of the residual energy after the ionization collision on the basis of experimental results. The reliability of the proposed electron collision cross section set is demonstrated by comparing the calculated and measured electron transport coefficients in a wide range of reduced electric fields, E/N (E: electric field strength, N: number density of gas molecules). Comparison of the values of the electron transport coefficients in N2 calculated from eight individual cross section sets partly provided on LXCat with the measured values is also carried out. Furthermore, the effect of anisotropic inelastic electron scattering on the electron transport coefficients is examined. The electron transport coefficients in N2 are found to be affected by considering anisotropic electron scattering with increasing E/N values, and the longitudinal third-order transport coefficient is found to be sensitive to considering anisotropic electron scattering even at middle E/N values. [ABSTRACT FROM AUTHOR]

Environmental radioactive contamination caused by the Fukushima Dai-ichi Nuclear Power Plant accident has aroused great concern regarding a possible increase in the incidence of childhood thyroid cancer. The ultrasound examinations were conducted immediately after the accident as part of the Fukushima Health Management Survey (FHMS), which is divided into the preliminary baseline survey (PBLS) and the full-scale survey (FSS). Some of their outcomes are reported regularly and made available to the public. We have detailed measurements of the air-dose rates and radioactive elements in soil in many places all over the Fukushima prefecture. To study the dose-response relationship, we begin with the assumption that the external and internal doses are correlated with the air-dose rate and the amount of 131I in soil, respectively. We then investigate the relationship between these estimated doses and the PBLS and FSS thyroid cancer cases. Our analysis shows that the dose-response curve with the FSS data clearly differs from that with the PBLS data. Finally, we consider the potential mitigating effects of evacuation from highly contaminated areas in both external and internal exposure scenarios. [ABSTRACT FROM AUTHOR]

A novel direct numerical method to calculate the electron velocity distribution function (EVDF) in hydrodynamic equilibrium under a uniform DC electric field is presented. In the present method, an artificial feedforward neural network learns the EVDF governed by both the Boltzmann equation and boundary conditions. The present method dost not require the expansion of the EVDF in the Legendre polynomials and the discretization of both the EVDF and the Boltzmann equation. As a benchmark, the EVDF in Reid's ramp model gas and Ar gas was calculated by the present method, and then the validity of the present method was demonstrated by comparing electron energy distributions and electron transport coefficients deduced from the EVDF with those calculated by Monte Carlo simulation. [ABSTRACT FROM AUTHOR]

Examines a method for measuring spatially resolved high-resolution nuclear magnetic resonance spectra for a spatially heterogeneous complex object by making images of several phantoms. Description of the examined method; Discussion on the factors which determine image quality; Comparison of the efficiency of the examined method with other methods.

SUMMARY: An artificial underground coal gasification (UCG) gas is generated by heating crushed coal, the artificial UCG gas is reformed by a packed‐bed dielectric barrier discharge (PB‐DBD), and then the reforming characteristics of the UCG gas are investigated. H2S, H2, CH4, CO, CO2, N2, and O2, which have been known as typical UCG gas components, are found to be contained in the gas, and alkanes (CnH2n+2), alkenes (CnH2n), and so on are also detected. When the UCG gas containing H2S of 400 ppm is reformed at an input power of 40W and a flow rate of 0.1 L/min, it is found that the decomposition rate and the decomposition efficiency of H2S are approximately 80% and 1.94 mmol/kWh, respectively, and that the production amount of H2 increases by approximately 14−40% and the production efficiency of H2 is 81.4 mmol/kWh. It is also found that the concentration of alkenes decreases obviously, while the concentration of alkanes is not affected significantly by discharge plasma reforming. This indicates that H2 may be produced from alkenes contained in the UCG gas by discharge plasma reforming. This leads that desulfurization and H2 production can be done simultaneously in a single reactor. [ABSTRACT FROM AUTHOR]

The article presents information on the architecture of craniocervical lymphatic vessels in rodents. Topics include the difference in the anatomy between human beings and mice, lymphatic vessels in mice being connected to each other via the small branches, and the superior location of the pterygopalatine fossa in the palate in mice.

Presents a study that synthesized the polycrystalline films of nonthermodynamical garnet bismuth[sub3]-iron[sub5]-oxygen[sub12] by direct epitaxial growth from the vapor phase. Preparation conditions of polycrystalline garnet layers; Temperature dependence of magnetization; Measurement of magnetic and magneto-optical characteristics.

Presents information on a study which synthesized nonthermodynamical garnet Bi[sub3]Fe[sub5]O[sub12] by direct epitaxial growth via vapor phase using a reactive ion beam sputtering technique. Use of the reactive ion-beam-sputtering method; Preparation of the bismuth-substituted iron garnet; Observation of the mazelike magnetic domains.

Provides information on a study that examined the effect on the optical and magnetic properties of adding tungsten or cobalt to Bi-substituted garnet films sputtered on glass substrates. Impact of adding a small amount of tungsten on the film; Factor that promotes development of magneto-optical memory using garnet sputtered film; Media ideal for magneto-optical memory applications.

The article discusses the carbocation of sulphur atom and degenerative chain transfer (DT) of carbon using thioethers. Information regarding the development of living cationic polymerisation, the molecular weight distribution of cyclohexyl vinyl ether, and the exploitation of atom transfer mechanism, are mentioned.