Determination of Copper in Aluminium Metals, Aluminium Alloys, and Steel by Atomic Absorption Spectrometry

Atomic absorption spectrometric determination of copper in aluminium alloys and steels was established, whereby a quite linear calibration curve was obtained for 0～40μg Cu/ml in 0.3～0.7N hydrochloric acid solution in the presence of aluminium (0.05～0.3 g/25 ml) and iron (0.1～0.5 g/25 ml). When the diethyldithiocarbamate-MIBK extraction was applied to the analysis of micro-amount of copper, the sensitivity of the method was ten-fold multiplied, and the 0.003% Cu in aluminium metal could be determined. The conditions recommended were as follows : wavelength 3247A, hollow cathode lamp current 30mA, slit width 0.025mm, air pressure 1.5kg/cm^2, and acetylene pressure 0.5kg/cm^2 for aqueous solution and 0.3kg/cm^2 for MIBK solution with the water cooling of the burner

Comparison of electromyogram reaction time at the onset of motion in badminton players at different competitive levels

In this study, we evaluated the electromyogram reaction time of femoral muscles at the onset of motion in college badminton players at different competitive levels, with the aim of clarifying the characteristics of the motor reaction processing in response to stimulation. The participants were seven male players from the team that won second place in the All Japan College Badminton Championship (high-performance group) and college badminton players with no experience in participating in national championship games (low-performance group). In both the 1-direction and 2-direction tasks, the action time was shorter, and the pre-motor time of femoral muscle activity was significantly shorter in the high-performance than in the low-performance group. In both tasks, significant differences were observed in the rate of increase in absolute EMG amplitude of the swing-out and push-out legs, and the values were higher in the high-performance than in the low-performance group. Results indicate that high-performance badminton players are able to move quickly by synchronizing the motor units of the rectus femoris muscle at the onset of motion and perform actions by exerting large joint torques.This work was supported by a Research Grant of the Health Science University

Synthesis, excited state properties, and dynamic structural change of photoresponsive dendrimers

AbstractThis article reviews recent advances in research of the dendrimer synthesis in connection with the design, synthesis and reaction of photoresponsive dendrimers. Dendrimers with photoreversible stilbene cores undergo mutual cis–trans isomerization in organic solvents to give photostationary state mixture of cis and trans isomers. Even the fourth generation (G4) stilbene dendrimer with molecular weight as high as 6500 underwent cis–trans photoisomerization within the lifetime of the excited singlet state. The large dendron group surrounding the photoreactive core may affect the excited state properties of the core to increase the efficiency of photoisomerization and/or decrease the fluorescence efficiency. The photochemistry of stilbene dendrimers with various types of dendron groups, and azobenzene dendrimers is discussed. Furthermore, recent advance of dendrimer syntheses and the possibility of their application to construct photoresponsive large molecules are discussed

Stabilization of the Plasma-Jet Flame and Determination of Aluminium and Boron in Steel

A stabilization of the plasma-jet flame was studied for the use of acid solutions, the apparatus was improved and working conditions for the determination of aluminium and boron in steel were examined. The coefficient of variation for the determination of aluminium (0.061%) in steel was 4.9%. These determinations are rather difficult by flame spectrometry or atomic absorption spectrometry using the usual combustion flame because of the formation of stable oxides of Al and B

Product Operations Status Summary Metrics

The Product Operations Status Summary Metrics (POSSUM) computer program provides a readable view into the state of the Phoenix Operations Product Generation Subsystem (OPGS) data pipeline. POSSUM provides a user interface that can search the data store, collect product metadata, and display the results in an easily-readable layout. It was designed with flexibility in mind for support in future missions. Flexibility over various data store hierarchies is provided through the disk-searching facilities of Marsviewer. This is a proven program that has been in operational use since the first day of the Phoenix mission