Radiolysis of aqueous 2,2,2-tribromoethanol solutions

1970 ◽  
Vol 48 (16) ◽  
pp. 2542-2548 ◽  
Author(s):  
V. G. Sorensen ◽  
V. M. Bhale ◽  
K. J. McCallum ◽  
R. J. Woods

Hydrogen bromide, glycolic acid, and carbon dioxide have been identified as products of the γ-radiolysis of aqueous 2,2,2-tribromoethanol solutions. The effect of oxygen, tribromoethanol concentration, and dose rate upon the yields of bromide ion and acid have been determined, and partial radiolysis mechanisms are proposed for reaction in the presence and absence of oxygen. Dibromoacetaldehyde, reported to be a product of the photochemical decomposition of tribromoethanol solutions, was not detected in the radiolysis experiments or in tribromoethanol solutions exposed to sunlight.

1978 ◽  
Vol 31 (4) ◽  
pp. 385 ◽  
Author(s):  
RN Murdoch ◽  
WD Davis

The metabolism of washed boar spermatozoa was studied in the presence and absence of low levels of bicarbonate (6 mM) and carbon dioxide (2 %). Bicarbonate stimulated the oxygen consumption of the spermatozoa but had no apparent effect on glycolysis. The stimulatory effect of bicarbonate on respiration depended on the presence of a utilizable exogenous energy source such as glucose, fructose, lactate, or pyruvate and no stimulation occurred when no substrate was added or when acetate was used as substrate. The response of the spermatozoa to bicarbonate also depended on the presence of adequate concentrations of potassium (5 mM) and to a lesser extent magnesium (1 mM).


1971 ◽  
Vol 179 (1056) ◽  
pp. 177-188

The effects of the composition and pressure of the ambient gas mixture on the diffusive gas exchange of leaves, and the effects of carbon dioxide and oxygen on respiration and photosynthesis are described. When photosynthesis is limited by the rate at which carbon dioxide reaches the chloroplasts, the net rate of photosynthesis of many (but not all) plant species depends on the ambient oxygen partial pressure. The effect of oxygen may be principally to stimulate a respiratory process rather than to inhibit carboxylation. However, when photosynthesis is not limited by the carbon dioxide supply, this respiratory process seems to be suppressed. The gas exchange of plant communities responds to the aerial environment in the way expected from measurements on single leaves, but the growth response to a given difference in gas composition is smaller than expected because of adaptation, notably in the ratio of leaf dry mass to leaf area. It is concluded that the growth rate of higher plants in given illumination will be independent of the partial pressure of oxygen and of other gases likely to be used to dilute it, provided that the carbon dioxide partial pressure is so adjusted (probably to not more than 2 mbar (200 Pa)) that the rate of photosynthesis is not limited by the rate of diffusion to the chloroplasts.


1960 ◽  
Vol 38 (3) ◽  
pp. 320-325
Author(s):  
Gordon M. Clark ◽  
Donald G. Baker

The basic biological action of radiation must initially involve particular cells. The sensitivity of various cells differs but some of the differences may be due to a dose-rate effect. When cells are irradiated with doses in the lethal range, inhibition of cell division occurs. A notable feature of mitotic inhibition is that it depends not only on dose but on dose rate. Chromosome breaks produced in cells may be a visible manifestation of an interruption in chemical synthesis produced by the passage of ionizing particles. The effect of oxygen is apparently of primary importance in biological changes produced by irradiation. Almost all are decreased in its absence. The current trend in research on the cellular level is towards determining the more obscure injuries which cannot be seen under the microscope.


2019 ◽  
Vol 245 ◽  
pp. 486-495 ◽  
Author(s):  
Fatima Magzoub ◽  
Xin Li ◽  
Jawad Al-Darwish ◽  
Fateme Rezaei ◽  
Ali A. Rownaghi

CORROSION ◽  
2005 ◽  
Vol 61 (11) ◽  
pp. 1086-1097 ◽  
Author(s):  
E. Gulbrandsen ◽  
J. Kvarekvål ◽  
H. Miland

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