The periodicity in the consumption of oxygen in Asellus aquaticus [Translation from: Vestnik ceskoslovenske zoologicke Spolecnosti, 15, 1, 89-97, 1951]

The consumption of oxygen in Asellus aquaticus was measured to find if there existed a periodicity in the consumption of oxygen and how this showed itself during the course of the day, year and in various experimental conditions. From the figures obtained comparative values were calculated and from these curves were plotted of the changes in the consumption of oxygen during the day and year

Early Phase Changes During the Setting of High Copper Amalgams

X-ray diffraction analysis has been used to evaluate the phase composition of two (spherical and lathe cut) HCSC amalgam alloys and early phase changes in these amalgam in the time interval 2.5 min to 7 days after trituration. A method appropriate for the evaluation of these changes was developed. Only two phases were found in alloys Valiant and Ana 2000: gamma(Ag3Sn) and epsilon(Cu3Sn). In amalgams, no diffraction peaks were observed corresponding to gamma 2 phase in the time interval form 2.5 min to 7 days after trituration. The relative concentration changes of the reaction products of an amalgamation (gamma 1 and eta) were observed already at 2.5 min after trituration. Twenty minutes after trituration there were some differences in the setting rate between spherical and lathe cut amalgams: the spherical amalgam rate was higher. The formation of the reaction phases was fastest during the first 60 min after trituration and continued for at least the next 7 days

On subsequential spaces

AbstractSimple generators for the coreflective category of subsequential spaces, one of them countable, are constructed. Every such must have subsequential order ω1. Subsequentialness is a local property and a countable property, both in a strong sense. A T2-subsequential space may be pseudocompact without being sequential, in contrast to T2-subsequential compact (countably compact, sequentially compact) spaces all being sequential. A compact subsequential space need not be sequential