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Relations between molecular structures of europium complexes and their luminescent properties were investigated. Europium complex with β-diketones and two different phosphine oxides 8 was highly soluble in fluorinated medium, and realized largest fluorescence intensities. The luminous intensity of ultraviolet light emitting diodes devices (LEDs) whose fluorescence layer consists of fluorinated polymer and 8 was over 200 mcd (20 mA). Fluorescence compounds of this type are promising for application in next-generation white LEDs. Moreover, we proposed a novel molecular design of europium complex with asymmetric diphosphine dioxide.

The 7 Li and 6 Li nuclear spin-lattice relaxation rates, ( 7 T 1 ) -1 and ( 6 T 1 ) -1 , have been measured for LiCoO 2 as a function of temperature. Comparison between 7 Li- and 6 Li-rich samples shows that the ratio ( 6 T 1 ) -1 /( 7 T 1 ) -1 =0.06 is considerably larger than the value expected for quadrupolar relaxation processes. Furthermore ( 7 T 1 ) -1 decreases significantly as 7 Li is replaced by 6 Li. These observations indicate that ( 7 T 1 ) -1 is dominated by the nuclear magnetic dipole-dipole interaction between the 7 Li nuclei. The substitution of Cr for Co has no effect on ( 7 T 1 ) -1 in the range below 200 K, whereas the substitution of Na for Li enhances ( 7 T 1 ) -1 . The substitution effect supports the view that the two-dimensional Li ion motion is dominant in LiCoO 2 . The weak dependence of ( 7 T 1 ) -1 upon temperature and frequency suggests the presence of a broad distribution of barrier heights for ionic motion in LiCoO 2 .

The lithium storage mechanism of perylene-based disordered carbon (PBDC) heat-treated at 550 °C, which is a promising material for use as the anode in lithium-ion cells, was studied by solid-state 7 Li NMR and ESR analysis. PBDC is one of carbonaceous materials containing condensed aromatic rings, and showed a high reversible specific capacity of about 800 mAh/g with large hysteresis in the charge/discharge profile. 7 Li NMR spectra for the lithiated PBDCs exhibited two bands at the insertion of above 900 mAh/g. Band A at 7 ppm and band B at 0.3 ppm versus LiCl were assigned to lithium in reversible and irreversible storage sites, respectively. The results of 7 Li NMR analysis supported the presence of ionic lithium located on aromatic rings. ESR spectra for PBDC lithiated by over 300 mAh/g showed sharp and broad signals. The intensity of the broad signal varied significantly with lithium insertion. The variations of 7 Li NMR and ESR spectra with lithium insertion were interpreted by the presence of two kinds of insertion sites: the layer structure site (L-site) and the unorganized carbon site (U-site) located between the L-sites.

A stable monolayer of a polymeric ion complex was formed at the air-water interface when dioctadecyldimethylammonium bromide was spread on an aqueous solution of potassium poly(vinyl sulphate). The polyion-complexed monolayer was annealed by a flat-panel heater located above the surface monolayer. The annealed monolayer deposited on an indium tin oxide electrode as a Y-type Langmuir-Blodgett film effectively blocked the electrochemical oxidation-reduction reaction of the ferricyanide ion.

In order to anneal the surface monolayer uniformly, a new trough system with a flat panel heater and a fluorescence microscope was constructed. The recrystallization process during thermal treatment of the monolayer was directly monitored by a fluorescence microscope. The crystal size of a double-chain ammonium monolayer was extremely increased by the thermal treatment. The practical advantage of the flat panel heater on the thermal treatment was demonstrated as a uniform size distribution of the crystalline domains.

For suppressing rocking mode vibrations of horizontal spindle-reciprocating table type surface grinding machines, special mounting elements with variable damping (Electro-Rheological Fluid type and Piezo-actuator type) are developed. By applying the special mounting elements to an existing surface grinding machine, damping effects of rocking mode vibrations are investigated experimentally. By using ERF enclosed mount, cross receptances of wheel head by table reversals are decreased about 20%. By using piezo stuck mount, these are decreased about 40%.

The 31P-NMR spectra of europium complexes with β-diketones and phosphine oxides in CDCl3, DMSO-d 6, toluene-d 8 with dissolved fluorinated polymers, and fluorinated solvent were investigated as well as the temperature dependence of these spectra. When a mixture of europium complex 1 and 1.0 molar equivalent of trioctylphosphine oxide and triphenylphosphine oxide was dissolved in a fluorinated solvent, europium complex 2 with two types of phosphine oxides was formed at room temperature. In CDCl3 and toluene-d 8 solutions, however, this complex was identified only at low temperatures. This difference is thought to be due to the differences in the speed of ligand exchanges. In DMSO-d 6 solution, no signal corresponding to the europium complex with phosphine oxides was observed. This implies that the major portion of phosphine oxides is not coordinated with europium ions in DMSO-d 6 solution. The fluorescence intensity of each europium complex in a solvent was correlated to the solvent and the 31P-NMR spectrum. It was found that the fluorescence intensity was the highest in the fluorinated solvent.