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This study was designed to evaluate trace metal metabolism in adults with thyroid diseases. Erythrocyte zinc values were significantly lower than normal in hyperthyroidism and higher in hypothyroidism. A significantly higher than normal urinary excretion of zinc was observed in hyperthyroidism. The mean concentrations of plasma and erythrocyte copper were significantly above normal in hyperthyroidism. Plasma selenium levels were significantly lower than normal in hyperthyroidism. No statistically significant difference was found in plasma zinc, erythrocyte manganese, or urine copper values between patients with thyroid diseases and healthy controls. The erythrocyte manganese content correlated well with thyroxine and triiodothyronine levels. Plasma prealbumin and retinol-binding protein correlated well with the erythrocyte zinc content but not with plasma zinc levels. There was no correlation between erythrocyte superoxide dismutase activity and erythrocyte copper or zinc concentrations. The results of this study suggest that the metabolism of zinc, copper, manganese, and selenium is abnormal in thyroid diseases.

The viscosity of molten SiO 2 -CaO-MgO-Al 2 O 3 slag was measured using a rotating cylinder method at high CaO and Al 2 O 3 concentration regions to search for a slag with low melting temperature and low viscosity. The experimental results showed that the viscosity of molten 35mass%Al 2 O 3 -43.1mass%CaO-7.5mass%MgO-14.4mass%SiO 2 slag at 1 673 K was lower than 0.6 Pa · s that satisfies the fluidity in blast furnace operation.The experimental results were compared with the calculated results of the viscosity model derived by the authors. The viscosity of molten SiO 2 -CaO-MgO-Al 2 O 3 system can be evaluated from our model in wide Al 2 O 3 concentration range.

In most previous works, liquid hold-ups were studied by using a cold model of a fixed bed soaked prior to experiments. However, they did not consider that the dripping zone of a blast furnace is saturated with liquids or with evenly distributed droplets. In the present study, the characteristics of liquid hold-ups and liquid flow were investigated by using a one-dimensional cold model of a fixed bed soaked and unsoaked prior to experiments (initially soaked and unsoaked beds). Packed balls were five kinds, the diameters (D p ) of which ranged from 5.4 to 30 mm. Tap water was used as liquid. Contact angles (q) for these particle/liquid systems were about 70°and 10°for fluorine-coated particles and non-coated particles, respectively.Although, under bad wettability condition (q Լ 70°), total and static hold-ups for initially unsoaked bed packed with small balls are remarkably smaller than those for initially soaked bed, the difference in their hold-ups between initially unsoaked and soaked beds decreases with increasing ball size in the bed. In initially soaked bed, total and static hold-ups increase monotonically as ball size decreases, which means the specific surface area increases. On the other hand, in initially unsoaked bed, total and static hold-ups under bad wettability condition indicate maximum values at about D p ϭ10 mm and decrease abruptly in proportion to a decrease in particle size, despite an increase in the specific surface area. Only restricted liquid droplets and/or liquid rivulets are formed within the packed bed with good wettability condition (qԼ 10°) for initially unsoaked bed, nevertheless liquid is easy to spread out on the solid surface. The influence of the initial bed condition, soaked or unsoaked bed, on liquid hold-ups is great under bad wettability condition.KEY WORDS: ironmaking; blast furnace; dripping zone; fixed bed; liquid hold-ups; particle/liquid wettability; initially soaked and unsoaked beds.

A ring chromosome 6 was identified in an apparently healthy girl with short stature and microcephaly. Of 100 peripheral lymphocyte metaphases analyzed, chromosome 6 was replaced in 73% by a monocentric ring chromosome, in 10% by a dicentric, in 1% by a tricentric, and 3% by two rings. Thirteen other cells were 45,XX,-6, which may represent 46,XX,r(6)/45,XX,-6 mosaicism. The breakpoints were located on bands p24 or p25 and q26 or q27. Eight other patients with a ring chromosome 6 have been reported. The most characteristic findings in subjects with a ring chromosome 6 are mental retardation and eye and ear abnormalities, none of which were present in our patient.