月別: 2017年7月

Analysis of Time Series of the Ambient Dose Rates [Published online J. Comput. Chem. Jpn. Int. Ed., 3, -, by J-STAGE]

[Published online Journal of Computer Chemistry, Japan -International Edition Vol.3, -, by J-STAGE]
<Title:> Analysis of Time Series of the Ambient Dose Rates
<Author(s):> Tomoo AOYAMA, Jun ASANUMA
<Abstract:> Radioactive substances are diffused by meteorological effects and soil property or underground water. The movements affect the ambient dose rate slowly and with smoothing in the long term. We detect the phenomena at monitoring posts in Fukushima. The monitoring post measures the flux from radionuclides; therefore, we discuss relations between the flux and mass density. Time-decreasing of the flux is a function of convection-diffusion of carriers of the nuclides. At the same time, it is also a decay function of radionuclides. We discuss product of the two functions, and get an expression for the time series of radioactive contaminated grounds. By using the expressions, we research changes of typical contaminants in Fukushima. This indicates movements of radionuclides.
<Keywords:> Radioactive cesium, Re-diffusion, Radioactive substance, Ambient dose rate, Forest fire
<URL:> https://www.jstage.jst.go.jp/article/jccjie/3/0/3_2016-0053/_html

Practical Training on Adding Polarization Function to Basis Set for Molecular Orbital Calculation of Ethylene [Published online J. Comput. Chem. Jpn. Int. Ed., 3, -, by J-STAGE]

[Published online Journal of Computer Chemistry, Japan -International Edition Vol.3, -, by J-STAGE]
<Title:> Practical Training on Adding Polarization Function to Basis Set for Molecular Orbital Calculation of Ethylene
<Author(s):> Shin-ichi NAGAOKA, Hiroyuki TERAMAE, Umpei NAGASHIMA
<Corresponding author E-Mill:> nagaoka(at)ehime-u.ac.jp
<Abstract:> Adding a polarization function to a basis set for molecular orbital calculation is frequently useful for producing accurate representations of chemical bonding. This article explains practical training that could greatly promote intuitive understanding of the general idea of adding a 3d-type polarization function in a π-type molecular-orbital function. In the training, by using Microsoft Excel, students draw contour plots of the molecular orbitals supplemented with and without the polarization function in ethylene (CH2 = CH2), and visualize the effect of the addition.
<Keywords:> Orbital contour plot, Polarization function, Ethylene, C2H4, Chemical Education
<URL:> https://www.jstage.jst.go.jp/article/jccjie/3/0/3_2016-0068/_html