Effect Of Aliphatic Acids Research Articles

Influence of aliphatic acids on the phase transition of thermoresponsive hyperbranched polymer

The influence of aliphatic acids on the phase transition temperature of thermoresponsive hyperbranched polyethylenimine possessing a large amount of isobutyramide and amine groups (HPEI-IBAm) was studied systematically. Nine saturated aliphatic acids including formic acid (C1), acetic acid (C2), n-pentanoic acid (n-C5), trimethylacetic acid (t-C5), hexanoic acid (C6), octanoic acid (C8), decanoic acid (C10), dodecanoic acid (C12) and hexadecanoic acid (C16) were used to measure their effects on the cloud point temperature (Tcp) of HPEI-IBAm in a mixture of H2O/DMF (v/v = 9:1). For comparison, the effect of these aliphatic acids on the traditional thermoresponsive linear poly(2-dimethylaminoethyl methacrylate) (PDMAEMA) and poly(N-isopropyl acrylamide) (PNIPAm) was also studied. The influence of aliphatic acids on different thermoresponsive polymers was different. The aliphatic acids with shorter carbon chains (C ≤ 8) increased the Tcp of HPEI-IBAm, and those with long hydrocarbon chains (C > 8) depressed the Tcp. Moreover, the effect of aliphatic acids with C ≤ 5 was similar, even though their configurations might be different. The specific ranking of aliphatic acids in raising the Tcp of HPEI-IBAm was as follows: C1 ～ C2 ～ n-C5 ～ t-C5 > C6 > C8 > C10 > C12 ～ C16. With respect of the linear PDMAEMA, all the aliphatic acids employed elevated its Tcp. The specific ranking of aliphatic acids in raising the Tcp of linear PDMAEMA was similar to that for dendritic HPEI-IBAm, but with a minor difference: C1 ～ C2 ～ n-C5 ～ t-C5 > C6 > C8 > C10 > C12 > C16. In the case of the linear PNIPAM, the aliphatic acids with C ≤ 6 had almost no influence on the Tcp. Raising the carbon number to be 8 or higher leads to the obvious Tcp depression. The different effect of aliphatic acids on the phase transition of these thermoresponsive polymers was discussed, and it was mainly attributed to their structural and topological difference.

Effects of aliphatic acids on seed germination and seedling growth in soil

Abstract It is commonly assumed that the adverse effect of plant residues on crop yields is largely, or partly, due to phytotoxic compounds leached from these residues or produced by their decomposition, and it has been suggested that the phytotoxic compounds responsible for reduced crop yields are aliphatic acids such as acetic acid, butyric acid, and propionic acid. To test the validity of this hypothesis, we studied the effects of different amounts of acetic acid, butyric acid, and propionic acid on seed germination and seedling growth of corn (Zea mays L.), barley (Hordeum vulgare L.), and wheat (Triticum aestivum L.) in soils. The data obtained showed that the aliphatic acids tested had adverse effects on seed germination and seedling growth only when the amounts applied were much greater than the amounts reported to occur in soils treated with plant residues. We conclude that the adverse effect of plant residues on crop yields is not due to aliphatic acids derived from these residues.

Effects of aliphatic acids on the metabolism and potency of fenitrothion in flour beetles

AbstractFormic, acetic, or n‐propionic acid applied with fenitrothion to Tribolium castaneum, inhibited the production of both fenitroxon and O‐desmethyl fenitrothion, but did not appear to affect metabolic attack on the P‐O‐phenyl link. These effects are comparable to those of some pyrethrum synergists. The toxicity of fenitrothion was synergised by formic or acetic acid, and antagonised by propionic acid, but these effects on potency were slight.

Effects of Aliphatic Acids and Their Salts on the Flame Spectormetric Emission of Calcium.

Effects of Aliphatic Acids and Their Salts on the Flame Spectormetric Emission of Calcium.