Identification of N1–Glycolylbiuret in the Gamma Radiolysis of Aerated Aqueous Solution of Cytosine. Influence of the pH

1984 ◽  
Vol 39 (1-2) ◽  
pp. 64-67 ◽  
Author(s):  
Michel Polverelli ◽  
Jacques Ulrich ◽  
Robert Teoule
Keyword(s):  
Aqueous Solution ◽  
Ph Effect ◽  
Gamma Radiolysis ◽  
G Value

Abstract N1 Glycolylbiuret, pH-Effect N1 glycolylbiuret has been identified as a radiation product of cytosine in aerated aqueous solution at pH 4.5. When varying the pH of the solution before irradiation from acidic values towards neutral ones. G value of N1 glycolylbiuret reached a maximum at pH 4.5.

Radiolysis of methylcyclopentane. III. Liquid phase mechanism and comparison of cycloalkanes

1968 ◽  
Vol 46 (20) ◽  
pp. 3235-3240 ◽  
Author(s):  
Gordon R. Freeman ◽  
E. Diane Stover
Keyword(s):  
Liquid Phase ◽  
Gas Phase ◽  
Bond Cleavage ◽  
Open Chain ◽  
Methyl Substitution ◽  
Product Yields ◽  
Total Ionization ◽  
Gamma Radiolysis ◽  
G Value

The initial yields of the major products of the gamma radiolysis of liquid methylcyclopentane (MCP) at 25° are: G(H2) = 4.2, G(1-methylcyclopentene plus methylenecyclopentane) = 2.7, G(3- plus 4-methyl-cyclopentene) = 1.0, G(open chain hexene) = 1.0, and G(bimethylcyclopentyl) = 0.9. The effects of scavengers on the product yields are reported and the mechanism is discussed.The liquid phase radiolytic decompositions of cyclohexane (CH), methylcyclohexane (MCH), cyclopentane (CP), and MCP are compared. The net amount of C—C bond cleavage is much greater in the five-membered than in the six-membered rings. Methyl substitution on the ring reduces G(H2) by about one unit, mainly because of the formation of a type of ion (QH+) that does not yield hydrogen when neutralized by an electron. The QH+ type ions are formed in MCH and MCP, but not in CH and CP. In all the systems, another type of ion (N+) that does not yield hydrogen when neutralized by an electron is formed with a G value of about unity. The type of ion (PH+) that does yield hydrogen when neutralized by an electron has a G value of 3.4 in CH and CP, but only 2.0 in MCP. It is concluded that G(total ionization) is in the vicinity of 4.4 in the liquid compounds, virtually the same as the gas phase values.

scholarly journals Gamma Radiolysis of Flavin Mononucleotide and Flavin-Adenine Dinucleotide in Aqueous Solution

1991 ◽  
Vol 64 (8) ◽  
pp. 2532-2538 ◽  
Author(s):  
Abhijit Saha ◽  
Parikshit Chandra Mandal ◽  
Sudhindra Nath Bhattacharyya
Keyword(s):  
Aqueous Solution ◽  
Flavin Adenine Dinucleotide ◽  
Flavin Mononucleotide ◽  
Gamma Radiolysis

Gamma-Radiolysis of Aqueous Solution of Histidine

1977 ◽  
Vol 32 (7-8) ◽  
pp. 482-487 ◽  
Author(s):  
Štĕpán Hrnčiř ◽  
Jiřina Kopoldová
Keyword(s):  
Aqueous Solution ◽  
Radiation Sensitivity ◽  
Butyl Alcohol ◽  
Free Medium ◽  
Gamma Radiolysis ◽  
Ph Range

The dependence of Gi( - M) values of histidine on the concentration of irradiated 10-4 -10-1 ᴍ solutions, pH and the presence of O2, N2O and sec-butyl alcohol was investigated. In oxygen-free medium the maximum radiation sensitivity of histidine was found at pH 5 - 8; in oxygenated solutions it was shifted to the 6 - 11 pH range. The formation of radiation products was also studied. The course of radiation decomposition of histidine depends on the presence of oxygen and on the pH of irradiated solution.

scholarly journals Removal of Erichrome Black T from Synthetic Wastewater by Cotton Waste

2011 ◽  
Vol 8 (2) ◽  
pp. 803-808 ◽  
Author(s):  
U. V. Ladhe ◽  
S. K. Wankhede ◽  
V. T. Patil ◽  
P. R. Patil
Keyword(s):  
Aqueous Solution ◽  
Activated Carbon ◽  
Chemical Kinetics ◽  
Contact Time ◽  
Ph Effect ◽  
Physicochemical Characterization ◽  
Synthetic Wastewater ◽  
Batch Adsorption ◽  
Experimental Parameters ◽  
Cotton Waste

Adsorptions of Erichrome Black T dye in aqueous solution on cotton stem activated carbon have been studied as a function of contact time, concentration and pH. Effect of various experimental parameters has been investigated at 39±1°C under batch adsorption technique. The result shows that cotton stem activated carbon adsorbs dye to a sufficient extent. The physicochemical characterization and chemical kinetics was also examined for the same dye. The overall result shows that it can be fruitfully used for the removal of dye from wastewaters.

Gamma Radiolysis of Aerated Aqueous Solution of Cytosine, III.

1976 ◽  
Vol 31 (5) ◽  
pp. 580-582 ◽  
Author(s):  
M. Polverelli ◽  
R. Teoule
Keyword(s):  
Aqueous Solution ◽  
Gamma Irradiation ◽  
Ring Cleavage ◽  
Radiolysis Products ◽  
Gamma Radiolysis

In gamma-irradiation of cytosine in aerated aqueous solution, two new radiolysis products were isolated and identified: 1-carbamoyl-5-hydroxyhydantoin and N-formylbiuret. This formation involves ring cleavage between C4 and C5 and belongs to the nondeamination pathway.

scholarly journals Adsorption of As(V) from Aqueous Solution on Chitosan-Modified Diatomite

2020 ◽  
Vol 17 (2) ◽  
pp. 429 ◽  
Author(s):  
Qintao Yang ◽  
Liang Gong ◽  
Lili Huang ◽  
Qinglin Xie ◽  
Yijian Zhong ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Removal Efficiency ◽  
Ph Effect ◽  
Freundlich Isotherm ◽  
Xrd Analysis ◽  
Optimal Value ◽  
Equilibrium Data ◽  
Pseudo Second Order ◽  
Adsorption Desorption ◽  
Modified Diatomite

A novel chitosan (CS)-modified diatomite (Dt) was prepared by a simple mixture in the mass ratio to remove As(V) from aqueous solution in this research. The CS-modified Dt adsorbent was characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray powder diffraction (XRD) analysis. The parameters to influence the adsorption of As(V) ion were studied under such conditions as kinetics, adsorption isotherm, and pH effect. The results revealed that adsorption of As(V) was initially rapid and the equilibrium time was reached after 40 min. The optimal value of the pH was 5.0 for better adsorption. The equilibrium data were well fitted to the Langmuir isotherm compared to the Freundlich isotherm, and exhibited the highest capacity and removal efficiency of 94.3% under an initial As(V) concentration of 5 mg/L. The kinetic data were well described by the pseudo-second-order model. In addition, 0.1 M NaOH has the best desorption efficiency of As(V) adsorbed on CS-modified Dt, and the removal efficiency of As(V) was still higher than 90% when after six adsorption-desorption cycles. These results showed that the CS-modified Dt could be considered as a potential adsorbent for the removal of As(V) in aqueous solution.

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