The hydrion concentration of plant tissues
In previous articles of this series we have given a general survey of the reaction of stem tissues in a number of families (5), a general survey of the tissue reactions throughout the life-periods of the sunflower (1) and of the bean (6), and also an indication of the possible importance of the carbon dioxide content as a factor governing the hydrion concentration of the cell, especially between pH 6"0 and pH 4"0 which is the usual range in plant tissues (2). In the present article we summarise the data obtained during a general survey of selected herbaceous and woody stems, examined at monthly intervals throughout the year.
THE INFLUENCE OF AMMONIUM SALTS ON CELL REACTION
1. It may be shown by means of cells of the flowers of a hybrid Rhododendron which contain a natural indicator, by means of starfish eggs stained with neutral red, and by means of an "artificial cell" in which living frog's skin is employed that increased intracellular alkalinity may be brought about by solutions of a decidedly acid reaction which contain ammonium salts. 2. These results are analogous to those previously obtained with the CO2-bicarbonate system, and depend on the facts: (a) that NH4OH is sufficiently weak as a base to permit a certain degree of hydrolysis of its salts; and (b) that living cells are freely permeable to NH4OH (or NH3?) and not to mineral and many organic acids, and presumably not at least to the same extent to ammonium salts as such.
Heat Transfer Analysis in Cooling System of Hydropower’s Generator
Cooling process of power plant generator is handled via air-cooled radiators in which the cooling water is supplied from lake with its water temperature varies from season to season. In this study, the effect of temperature fluctuations of cooling water entering the cooling system has been examined via analysis of energy (NTU method) and exergy. The exergy analysis has been done by definition of efficiency coefficient for exergy of cooling media (water) and heating media (air). Besides, the effect of changing the cooling water temperature and flow rate entering the radiators on the cooling system performance has been studied. The results revealed the generator cooling system performance level held sufficient till the temperature of inlet water was kept under 293 k (20°C). On one hand, when the temperature of cooling water at the inlet rises to 12°C, the rate of heat exchange at radiators falls up to 34.3%. On the other hand, by water temperature passing the 12°C limit, the efficiency of cooling media exergy falls to 78% leading to efficiency rise in radiators’ heating media exergy level to 61%. According to the results of this study, changing flow rate of cooling media up to 40% gives rise to the efficiency coefficient of radiators’ cooling media exergy level to about 18.7%. While it does not affect the efficiency level of energy at radiators, the flow rate rise of cooling media may not be considered as a way to give rise to efficiency level of radiators.