Authors: S. Fujita On the radiolysis of uridine and some other nucleosides in aqueous solution, a pH-dependent liberation of uracil or the corresponding base was found. e and HO-2 gave no freed bases, although many oxidizing radicals, including OH, Cl2, Br2, (CNS)2 and SO4, did cause the release of unaltered bases, depending on the pH of the solutions. The base…
Authors: N. Hayashi, E. Hayon, T. Ibata, N. N. Lichtin, A. Matsumoto The pulse radiolysis of the following liquid amides has been investigated: formamide (F), N-methylformamide (NMF), Ar,Ar-dimethylformamide (DMF), AqAr-dimethylacetamide (DMA), and Ar-methylpropionamide (NMP). Radiation-induced ionization and excitation processes have been observed on irradiation of solu- tions of anthracene (A) and naphthalene (N), as indicated by the characteristic spectra of…
Authors: J. H. Baxendale, R.D. Sedgwick The yields of hydrogen, formaldehyde, ethylene glycol, methane and carbon monoxide from the radiolysis of methanol vapour have been measured and also those of H2 and HD from CH3OD. These have been correlated with the ions observed in the mass spectra. Benzene decreases the yields of hydrogen and formaldehyde and the effect is attributed…
Authors: I. A. Taub, L. M. Dorfman The radiation chemistry of deaerated aqueous ethanol and deaerated liquid ethanol has been studied by the pulse radiolysis technique. The same transient absorption spectrum, showing a broad weak absorption at about 290 mU and stronger narrow peaks at 266, 257 and 247 mU, has been observed in both systems. It is concluded that…
Authors: N. K. Kochetkov, L. I. Kudrjashov, M. A. Chlenov, L. P. Grineva The mechanism of the radiation-induced dephosphorylation reaction was investigated by studying the γ-radiolysis of 10mM solutions of D-glucopyranosyl phosphate, D-glucose 6-phosphate (Glc-6-P), and d-ribose 5-phosphate (Rib-5-P). Dephosphorylation occurred with OH-radical participation, since G(H3PO4) values for nitrous oxide-saturated solutions were 4.1, 1.7, and 2.3, and for nitrogen-saturated solutions…
Authors: T. W. Woodward, H. C. Sutton Aliphatic alcohols increase the yields of N2O observed in the radiolysis of NO solutions and are oxidized to the corresponding aldehyde in the process. The following reactions occur in addition to those previously suggested 1 for the NO radiolysis: OH+ROH → H2O+˙ROH ˙ROH+3NO → N2O+HNO2+R˙= 0(aldehyde) where R = Me, Et, i-Pr. https://doi.org/10.1039/TF9666200070
Authors: M. Simic, P. Neta, E. Hayon A detailed pulse radiolysis study of aqueous solutions of methanol, ethanol, isopropyl alcohol, n-, iso-, and t-butyl alcohols, neopentanol, and eyelohexanol has been carried out. Optical absorption spectra of some of the transients have been measured down to 210 nm. Similar spectra were obtained in liquid methanol, ethanol, and isopropyl alcohol. Absorption maxima…
Authors: M. P. Robertson, S. L. Miller IN contrast to the purines, the routes that have been proposed for the prebiotic synthesis of pyrimidines from simple precursors give only low yields. Cytosine can be synthesized from cyano-acetylene and cyanate; the former precursor is produced from a spark discharge in a CH4/N2 mixture and is an abundant interstellar molecule. But this…
Authors: R. Osterberg, L. E. Orgel When ammonium dihydrogen phosphate is heated with urea to temperatures in the range 85–100°C, it polymerizes almost quantitatively to give polyphosphates containing, on the average, more than ten (PO3) residues. Similar experiments carried out at 72°C give polyphosphate in more than 60% yield. If a nucleoside (thymidine or 3′-deoxythymidine) is added to the reaction…
Authors: R. L. Hudson Radiation processing of cometary, planetary, and interstellar ices has been investigated by irradiating mixtures of H2O and CO near 16 K with 0.8-MeV protons. IR spectroscopy and isotopic substitution showed that H and OH, from H2O, added to CO to form HCO, H2CO, HCOOH, and CH3OH. A values (integrated spectral absorbances) for HCOOH and HCO trapped…