Ni-PTFE (PolyTetraFluoroEthylene) composite film was formed on hydrogen storage alloy (MH alloy) powder particles by means of electroplating method. MH alloy powder (mean diameter, 50 μm) with the composition of MmNi_3.65Co_0.75Al_0.25Mn_0.35 (Mm denotes Misch metal) was used. The electroplating apparatus equipped with rotating bath was designed to electroplate the Ni-PTFE composite film on the MH alloy powder particles. The bath was rotated at high speed (350 rpm) to make electrical contact between the particles and the belt-ring cathode made of titanium placed on the inside wall of the bath. The electrolyte solution added MH alloy powder and PTFE powder was agitated by intermittent rotation. PTFE powder particle (mean diameter, 5 μm) was suspended in the electrolyte solution with a cationic surfactant.
The electroplating efficiency on the MH alloy powder was calculated to be 60%. The Ni-PTFE composite film was uniformly deposited on the individual particle, and was observed to be a little bit porous. The surface area after plating was 3.5 times larger than that of the original alloy powder. As the results of PCT) (Pressure Composition Temperature) measurement, characteristics of hydrogen gas absorption-desorption such as the equilibrium pressure, the absorption amount and the hysteresis were found to be maintained. The corrosion resistivity in a strong alkaline solution was extremely enhanced. Even after immersing in 6 mol dm⁻³ KOH at 70 °C for 72 h, no formation of Mm(OH)₃ on the surface of Ni-PTFE plated MH alloy was detected, and especially, the dissolving Mn decreased to less than one twentieth amount of original MH alloy.

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The Krafft and melting points of n-alkylammonium and α,ω-alkanediammonium 1-alkanesulfonates were measured by the change of transmittance and the dependence of conductivity on temperature under the coexistance of its solid, respectively. Melting points for these surfactans showed the odd-even changes by the change of carbon chain lengths in their counter cations. The Krafft points for the α,ω-alkanediammonium salts also showed the odd-even changes. The Krafft points for the n-alkylammonium salts did not show clearly the odd-even changes when the carbon number of the counter cation was less than 4 but showed the changes when the carbon number was more than 4. The odd-even changes for their heats of dissolution were obtained by an analogy from the dependence of the conductivities of their saturated solution on temperature. Their odd-even changes were similar to those of Krafft points.

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In order to determine the molecular geometries of 1-methyl-2(1H)-pyridinimine (1MPI: abbrev.) in the ground and lowest excited singlet (S₁: abbrev.) states, the RHF/6-31 + G(d) and RCIS/6-31 + G(d) methods were carried out.
And also the IR spectrum was measured to determine the existence of the cis-form of 1MPI with respect to the configuration of the C=NH group in the ground state. From calculated and spectroscopic results the following conclusions were drawn: (1) The ring frame-work of 1MPI in the ground state is planar within the precision of the present calculation. (2) In the S₁ state the ring frame-work is nonplanar. The energy difference between the nonplanar and planar structures is 0.34 kJ mol⁻¹. (3) The S₁ state of 1MPI is of π, π^* character. There are three n, π^* singlet states between the S₁ and second π, π^* singlet states. These n, π^* singlet states are close lying to the S₁ state. (4) Although the S₁ state is of π, π^* character, its state is partially of n, π^* character due to the nonplanarity of the ring frame-work. Therefore, the S₁ state may be mixed easily with the near-lying n, π^* excited states through the vibronic-coupling and spin-orbit coupling. These couplings lead to the nonradiative deactivation of the S₁ state. The reason of low fluorescence quantum yield of 1MPI may be attributed to the nonplanar structure in the S₁ state and existence of the n, π^* singlet states close to the S₁ state. (5) The trans-form with respect to the H atom of C=NH group of 1MPI to the ring N atom is more stable than the cis-form. The calculated potential barrier height for the trans-cis isomerization process suggests that the trans-cis isomerization is more easy in the lowest excited singlet state than in the ground state. The IR spectrum of 1MPI irradiated by the UV light showed the existence of the small amount of cis-form increased with the UV irradiation and with the concentration of 1MPI. (6) The degree of deformation of molecular structure of 1MPI is smaller than those of 2-pyridone and 1-methyl-2-pyridone in the lowest excited single state. The shape of vibrational structure of fluorescence spectrum of 1MPI is different from those of the other ones. This result is related to the difference in the degree of deformation of molecular structure between 1MPI and 2-pyridone and 1-methyl-2-pyridone.

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Effect of chemical structure on drag reduction behaviors of quaternary ammonium salt cationic surfactant solutions in the presence of sodium salicylate (NaSal) was investigated in terms of 1) alkyl chain length and 2) number of 2-hydroxyethyl groups. From the present investigation, we can draw the following conclusions;
   1) Increasing in alkyl chain length in the quaternary ammonium salt in the presence of NaSal increased the maximum temperature at which drag reduction can be sustained.
   2) The presence of the double bond in alkyl chain had a significant effect on lower temperature drag reduction limit.
   3) The DR effect of HMODA complexed with NaSal, which was replaced the methyl groups in TMODA with two 2-hydroxyethyl groups, gave better drag reduction in the wide temperature range 6–60 °C.

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Effect of temperature on drag reduction behavior of quaternary ammonium salt cationic surfactant solutions with sodium salicylate (NaSal) was investigated in terms of 1) alkyl chain length and 2) number of 2-hydroxyethyl groups. Characterization concerning DR effect, pressure loss, first normal stress difference (N₁) and aggregate size for NaSal/cationics solutions were carried out. NaSal/cationics solutions containing above 40 nm-sized aggregation had a large DR effect ranged from 65–80%. However, the effect suddenly changed to 5–7% below 30 nm in aggregate size. The aggregate size apparently plays an important role in DR effect.

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In order to elucidate the mechanism of Drag Reduction (DR) effect in a turbulent pipe flow, properties of aggregates in NaSal/HMODA solutions were measured under shear by means of flow birefringence and rheometry. DR effect appeared when the molar ratio of NaSal/HMODA was above 0.5. As the molar ratio was further increasing, it tends to have good drag reducing abilities up to higher Reynolds number. To ascertain the formation of structural association under shear, the first normal stress difference (N₁) for various molar ratio of NaSal/HMODA was measured as a function of shear rate. The N₁ for HMODA solution without NaSal decreased as the shear rate increased. This is characteristic for a Newtonian fluid. However, when the molar ratio of NaSal/HMODA increased to above 0.5, the values for N₁ first increased slowly up to about shear rate of 500 s⁻¹, after which they settled down to a plateau. It is suggested that they underwent structural associations which were due to the formation of shear-induced structure (SIS) when a critical value of the shear rate was exceeded. Based on these results, it was found that the formation of SIS played an important role in DR effect.

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The direct photocyclization of four 1,4-diarylcyclohepta-1,3-dienes(1a–d) with different aryl groups (phenyl, 1-naphthyl, and 2-naphthyl groups) by a XeCl excimer laser (308 nm) in hexane gave 1,5-diarylbicyclo[3.2.0]hept-6-enes (2a–c). The efficiency of the photochemical cyclization and fluorescence quantum yield strongly depended upon the aromatic substituents and this is interpreted by the conformation of the molecules.

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