Some Relationships between Molecular Structure, pH and the Ability of Bacteria to Grow in Solutions of Salts of Organic Acids

1935 ◽  
Vol 57 (8) ◽  
pp. 1495-1503 ◽  
Author(s):  
William F. Bruce
Keyword(s):  
Molecular Structure ◽  
Organic Acids ◽  
Salts Of Organic Acids

Magnetic behaviour and structure of polymeric oxovanadium carboxylates

1972 ◽  
Vol 25 (6) ◽  
pp. 1195 ◽  
Author(s):  
AT Casey ◽  
BSSE Morris ◽  
JR Thackeray
Keyword(s):  
Molecular Structure ◽  
Magnetic Properties ◽  
Organic Acids ◽  
Electronic Spectra ◽  
Magnetic Behaviour ◽  
Antiferromagnetic Exchange ◽  
Broad Maximum ◽  
Linear Chains ◽  
Salts Of Organic Acids ◽  
Infinite Linear

The synthesis and properties of a series of oxovanadium(1V) carboxylates (i.e. salts of organic acids) are described. The complexes closely resemble each other in magnetic properties, the observed paramagnetism being abnormally low for oxo-vanadium(1V) in the temperature range 90-350 K, with a broad maximum around 200-250 K. After testing of all reasonable models, the magnetic properties are interpreted in terms of anisotropic (Ising) antiferromagnetic exchange along infinite linear chains of interacting spins. On the basis of this model and with the aid of infrared, e.s.r., and electronic spectra, the most probable molecular structure for the series of complexes can be given. In our interpretation of the evidence, the interactions are of the super-exchange type.

Proflavine binding and release by sensitive and resistant Bacillus subtilis

1970 ◽  
Vol 16 (10) ◽  
pp. 973-981
Author(s):  
Gy. Barabas ◽  
B. M. Mehta ◽  
D. J. Kushner
Keyword(s):  
Escherichia Coli ◽  
Bacillus Subtilis ◽  
Organic Acids ◽  
Resistant Strain ◽  
Binding Capacity ◽  
Sensitive Strain ◽  
Growth Media ◽  
Sodium Salts ◽  
Salts Of Organic Acids ◽  
Resistant Cells

Proflavine binding of a sensitive strain of Bacillus subtilis and of a resistant strain derived from it was compared. Proflavine was bound very rapidly and more was bound at 0 °C than at 37 °C. Boiling increased the proflavine-binding capacity at 37 °C of sensitive but not of resistant cells. The binding capacity of sensitive and resistant cells suspended in buffer was the same; this was also true in various growth media. If cells were able to grow in the presence of proflavine their proflavine content decreased.Bound proflavine was released when cells were treated with growth media or with the salts of growth media. Sodium salts of organic acids also caused a release. This effect seemed due to their Na+ content, and was somewhat higher for resistant than for sensitive cells. The mechanism of proflavine resistance in B. subtilis is probably different from that of Escherichia coli, which is thought to depend on an energy-driven release of bound proflavine.

Effect of Metallic Poisons. Especially Manganese, on Aging of Vulcanized Natural Rubber

1947 ◽  
Vol 20 (3) ◽  
pp. 821-826
Keyword(s):  
Organic Acids ◽  
Natural Rubber ◽  
Harmful Effect ◽  
Manganese Compound ◽  
Naturally Occurring ◽  
Different Types ◽  
Salts Of Organic Acids ◽  
General Experience ◽  
Manganese Compounds ◽  
Harmful Effects

Abstract 1. Information received from rubber manufacturers on their experience of the effects of manganese and copper on aging is summarized. Although there is evidence that the amounts of these impurities in fillers tended to increase during the early war years (1939–42), it seems to be the general experience that little trouble arose from their effects on the properties of the rubber. Fillers containing as much as 0.05–0.10 per cent of manganese, or 0.005 per cent of copper, have not shown any obvious harmful effects. 2. Experiments with a large number of manganese compounds, including naturally occurring (mineral) forms and salts of organic acids, used in amounts equivalent to 0.01 per cent manganese on the raw rubber, have failed to show any pronounced harmful effect on the aging (oven or oxygen bomb) of a vulcanized natural rubber containing mercaptobenzothiazole, although deterioration was noticeably accelerated in some cases. Probably on account of the smallness of the effects observed, it is not possible as yet to draw any conclusion as to the relative activities of different types of manganese compound. 3. According to results of previous workers, manganese in the amount used in the present experiments can produce a more serious effect than these experiments indicate. The effect of manganese is known to depend on the type of mix used, and this aspect of the problem would thus appear to merit further investigation, as does also the influence of the method and degree of dispersion of the manganese compound in the rubber mix.

A Quinonoid Structure for Hydroquinone Pyridinium Salts of Organic Acids

Nature ◽  
1949 ◽  
Vol 163 (4145) ◽  
pp. 565-566 ◽  
Author(s):  
ABDEL FATTAH ALY ISMAIL
Keyword(s):  
Organic Acids ◽  
Pyridinium Salts ◽  
Salts Of Organic Acids
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