The absorption efficiencies of 6–, 10–, IS–, and 60-turn spiral contact columns for two formulations of Saltzman reagent are evaluated for use in atmospheric nitrogen dioxide analyzers at several air and liquid flow rates. Response times for the several columns as a function of flow rates and absorbing reagent are also given. The recommended column and reagent are indicated. The technique of adjusting instrument parameters for direct readout of NO2 concentrations is described.
Abstract In transmission systems of modulated data or picture signals, bandpass filters are required with symmetrical amplitude and delay characteristics around their own center frequencies on an arithmetic frequency scale. In variable attenuation equalizers, etc., band‐elimination filters are required with arithmetically symmetrical stopband amplitude characteristics around the center frequency. This paper proposes frequency transformations to make an analog bandpass filter and a band‐elimination filter (with geometrically symmetrical amplitude characteristics around the center frequencies that are obtained through reactance frequency transformation from analog lowpass filters) into a digital bandpass filter and a band‐elimination filter with arithmetically symmetrical amplitude characteristics. This transformation maps the positive imaginary axis and the negative real axis of analog frequency S to the real axis and the upper half of the unit circle on the z‐plane. the interval on the unit circle of the z‐plane mapping of the positive imaginary axis of the S‐plane is designed to cover the specified frequency region. This is done by controlling the locations of geometrically symmetrical two frequency points around the center frequency of bandpass (band‐elimination) filter by adjusting the parameters of lowpass‐bandpass (band‐elimination) transformation. Some design examples are also shown.
An investigating of docking structure and dynamics between metalloprotein is interested from the viewpoint of searching the function of protein. We investigate the cytochrome c551 and azurin complexes by three computational methods, quantum mechanical calculation, docking searching algorism and molecular dynamics simulation. At first we present the docking structure of the cytochrome c551‐azurin complexes expected by ZDOCK searching algorism. Quantum chemical calculation is tools to estimate the charge distrubution around the active site for each protein and force field parameters. From these parameters, we reproduce the protein docking dynamics by molecular dynamics simulation. We analyze some physical properties of complex system such as binding free energy, dynamical cross correlation map, and so on. We discuss the docking stability and dynamical effect of the cytochrome c551‐azurin complexes.
This paper proposes sign summation (SS) images for robust image registration against noises. An SS image is generated as the summation of the signs of the differences between the focused pixel and some of its neighboring ones. For image registration in subpixel accuracy, phase-only correlation or cross-correlation is applied to SS images rather than nonprocessed images. Experimental rusults show that SS imaging improves estimation accuracy, whereas median filter, a well-known impulse noise suppression filter, degrades the accuracy.