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The synthesis, characterization and properties of the sulfur-bridged cubane-type molybdenum gallium clusters were discussed. These clusters were obtained from the reaction of cluster [Mo3S4(H2O)9]4+ with gallium metal. The cyclic voltammogram of molybdenum-iron cluster is very similar to those in the cyclic voltammogram of [Mo3GaS4(H2O)12]6+, which shows three reduction processes; the cathodic peak potentials, Epc are -0.83, -1.20 and -1.74, respectively.

The effects of oxygen partial pressure during thermal treatment on the color and microstructure of Bizen, a traditional Japanese stoneware, were studied through model experiments using clay pellets covered lightly with rice straw as a coloring assistant. When heated in flowing nitrogen, the model pellet turned blackish owing to the formation of α-Fe particles coated with graphite. However, schreibersite (Fe3P), which is also blackish, was formed specifically on the pellet surface in direct contact with the straw. The rice straw seems to have generated a strongly reducing atmosphere, strong enough for the metallization to α-Fe, and also to have provided phosphorus through contact. When oxygen content in the surrounding gas atmosphere was raised to N2/O2=99/1, the pellet surface turned yellowish brown because the main coloring material was Fe3+-containing mullite. At oxygen contents of N2/O2=98/2 or more, the formation of hematite (α-Fe2O3) pushed the color to deep red. [ABSTRACT FROM AUTHOR]

Examines the effects of wall distance and velocity ratio of suction flow to injection flow on the flow and heat characteristics of a circular impinging jet. Impact of suction flow on the Nusselt number; Existence of a optimum velocity ration; Association of heat transfer characteristics with the fluctuating and mean velocity.

The current transformer used in a conduction detector switch circuit for lighting up an light emitting diode (LED) for detection of Load current in distribution lines has to be small and of Low excitation current. Since field- annealed Fe-based amorphous cores have high saturation magnetization and the squareness ratio of a hysteresis loop and low coercive force, current transformers that are superior to ferrite cores can be designed. Furthers more, in cases where reliability is required over long periods such as in LED lighting circuits, for the purpose of design, it is necessary to predict what influence is exerted on the circuit characteristics by the aging variations of the amorphous magnetic characteristics [1, 2]. Therefore, recently, based on a prediction method of dc coercive force researched by the present authors [3], aging variation prediction was carried out on ac (60 Hz) coercive force. Next, the ac magnetic characteristics of Fe-based amorphous cores were approximated by Potter's model [4], LED circuit analysis was carried out by application in a Spice program, and good agreement with experimental results was confirmed. hi addition, using the prediction values of aging variation of the cores, on deducing the effect of influence on circuit characteristics it was found that the degradation of LED circuit characteristics at 100°C and 106 hours of elapse was minimal, and it is possible to predict the maintenance of excellent characteristics better than in the case of ferrite cores. [ABSTRACT FROM AUTHOR]