Effect of γ-Irradiation on Aqueous Solutions of the Cyclic Dodecapeptide Polymyxin B

1968 ◽  
pp. 472-479 ◽  
Author(s):  
J. KOPOLDOVA
Keyword(s):  
Aqueous Solutions ◽  
Polymyxin B ◽  
Γ Irradiation

The epimerisation of monosaccharides by γ-irradiation in frozen, aqueous solutions

1973 ◽  
Vol 28 (1) ◽  
pp. 86-88 ◽  
Author(s):  
N.K. Kochetkov ◽  
L.I. Kudrjashov ◽  
M.A. Chlenov ◽  
T.Ya. Livertovskaya
Keyword(s):  
Aqueous Solutions ◽  
Γ Irradiation

scholarly journals Hydrogels Obtained via γ-Irradiation Based on Poly(Acrylic Acid) and Its Copolymers with 2-Hydroxyethyl Methacrylate

2020 ◽  
Vol 10 (14) ◽  
pp. 4960 ◽  
Author(s):  
Marin Micutz ◽  
Rodica Mihaela Lungu ◽  
Viorel Circu ◽  
Monica Ilis ◽  
Teodora Staicu
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Acrylic Acid ◽  
Aqueous Solutions ◽  
Functional Groups ◽  
Chemical Transformations ◽  
Hydroxyethyl Methacrylate ◽  
Γ Irradiation ◽  
Crosslinking Degree

Hydrogels containing both carboxyl and hydroxyl functional groups have been prepared by γ-irradiation of either aqueous solutions of acrylic acid (AA) and mixtures of AA and 2-hydroxyethyl methacrylate (HEMA) in different ratios, or aqueous solutions of poly(AA), PAA, and poly(AA-co-HEMA) obtained via solution polymerization. A higher absorbed dose is required in order to prepare hydrogels from monomer solutions, compared with those from polymer solutions. The range for the absorbed doses was chosen so that the probability of crosslinking reactions is higher than that of degradation ones. As the radiation energy deposited in a sample increases, the equilibrium swelling degree and the average molar mass between crosslinks diminishes. Chemical transformations induced by radiation were investigated by means of FTIR spectroscopy and thermal analysis of polymers before and after irradiation. For all these systems, the formation of a three-dimensional network enhances the glass transition temperature and thermal stability, but a further increase in the crosslinking degree may have the reverse effect on the glass transition temperature. Depending on the preparation protocol and/or hydrogel composition, superabsorbent materials that can bind different compounds throughout side functional groups may be obtained.

Free-Radical Reductions of Arenediazonium Ions in Aqueous Solution. VI. On Iododediazoniation

1985 ◽  
Vol 38 (6) ◽  
pp. 991 ◽  
Author(s):  
JE Packer ◽  
RER Taylor
Keyword(s):  
Aqueous Solution ◽  
Free Radical ◽  
Aqueous Solutions ◽  
Major Product ◽  
Chain Reaction ◽  
Γ Irradiation ◽  
A Chain

γ-Irradiation of aqueous solutions of p-ClC6H4N2+BF4- and KI initiates a chain reaction in which dichloroazobenzene is the major product. When iodine is also present the chain reaction is longer and the major product is chloroiodobenzene . The reaction � ������������������������� I2-·+ArN2+ → I2+Ar·+N2 is suggested to be propagation step in both reactions, with Ar · reacting with I3- in the presence of iodine and with ArN2+ in its absence. The relevance of these reactions to iododediazoniation is discussed.

Sign in / Sign up

Export Citation Format

Share Document