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[en] With the aid differential-thermal and X-ray phase analysis as well as of the complex metnod of stepwise annealing and ''hydration'' it has been established that upon heating potassium silicotungstate in air up to 900 deg C the decomposition process is described by the following equation K⁴[SiW¹²O⁴⁰]→2K₂W₆O₁₉+SiO₂. Upon heating in a hydrogen flow the decomposition of potassium tungstate gives rise to the formation of metal tungstate and is described by the equation: 2K₄[SiW₁₂O₄₀ H₂]yields 3K₂WO₄+K₂Si₂O₅+21W+31.5H₂O

[en] Prussian blue was used to enhance the elimination of ¹³⁷Cs from 46 individuals contaminated in an accident in Goiania, Brazil, in 1987. PB dosages administered to the victims varied from 1 to 3 g.d^-1 for children and from 3 to 10 g.d^-1 for adolescents and adults. To complement human data in the evaluation of the effectiveness of PB and its relation to age, a 41 day study was conducted using immature (4.7 months old), young adult (2.4 years old) and aged (13.5 years old) male beagle dogs. The mean biological half-times for the Goiania people under PB treatment were 24 ± 3 days, 30 ± 12 days and 25 ± 11 days, for children, adolescents and adults, respectively. The mean reductions of half-times were 43%, 46% and 69%, respectively. The effect of PB was shown to be independent of age and the administered dose. Similar results were found in dogs: the mean biological half-times related to the second component of the equation were 11, 15 and 13 days for the immature, young adult and aged dogs, respectively, indicating a reduction of the clearance half-times of 45%, 45% and 63%. The experiment in dogs has shown that when the PB is administered immediately after caesium intake, its effectiveness is greater in immature than in aged dogs. The percentages of the initial body burden remaining 41 days after caesium intake were 4%, 12% and 8% for the immature, young adult and aged dogs, respectively. This age-related effect correlates with the increased fraction of ¹³⁷Cs eliminated with the fast clearance half-time, and was greater in immature than in aged dogs. (author)

[en] Lithium and sodium insertion into the layered host materials KV₃O₈ and K₃V₅O₁₄ has been studied. KV₃O₈ has a very high stoichiometric capacity for lithium insertion and good cycling properties, which make it an interesting material for use in secondary lithium cells. K₃V₅O₁₄, which has a very open structure, inserts lithium and sodium ions at unusually low potentials, probably due to inadequate shielding of coulombic guest-guest interactions. (author). 7 refs.; 4 figs

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[en] Short communication

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[en] Published in summary form only