Experimental study of different regimes of low-gas compound combustion in argon at atmospheric pressure

To study the possibilities of occurrence of a low-temperature steady-state combustion regime and to determine the existence regions of other regimes in more detail, we performed experiments on combustion of low-gas compounds in argon at atmospheric pressure. As a model system, we used a diluted ferro—zirconium thermite with a gas-forming admixture of molybdenum trioxide. The absence of a low-temperature steady-state combustion regime and a change in the existence regions of the other combustion regimes for low-gas systems compared with those observed for combustion in air were revealed. Institute for Structural Macrokinetics, Russian Academy of Sciences, Chernogolovka 142432. Translated from Fizika Goreniya i Vzryva, Vol. 33, No. 1, pp. 69–72, January–February, 1997.     

An evaluation of the differences in human evoked cortical potentials to visual stimuli

Saccharomyces cerevisiae nuclei possess a polyphosphatase activity which is insensitive to a number of inhibitors of ATPase and pyrophosphatase (PPase) activities of the same organelle. Heparin, an effective inhibitor of the nuclear polyphosphatase activity, does not alter either the ATPase and PPase activity. The nuclear polyphosphatase activity is optimal at pH 7.5. Bivalent metal cations stimulate this activity in the following order: Co2+ > Mg2+ > Zn2+ > Mn2+. However, the magnitude of the stimulating effect is much lower than that for the polyphosphatase activities from other organelles of the same yeast. The polyphosphatase activity is nearly the same for polyphosphates ranging from [symbol: see text] = 9 to [symbol: see text] = 208, but is 1.5 times higher for tripolyphosphate. The K(m) values for the hydrolysis of polyphosphates with chain lengths [symbol: see text] = 3, 15 and 208 are 100, 5 and 4.1 microM, respectively. The polyphosphatase activity differs in some properties from that of the cell envelope, cytosol and vacuoles of the same S. cerevisiae strain.