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Cross-linked polyacrylonitrile PAN granules were prepared at ambient temperature by γ-rays at a constant dose rate of 8.5 kGy/h. It was found that the rate of polymerization was linear with the radiation dose at the initial stage of polymerization, and then, at high conversion, it tends to level off above 35 kGy. Cross-linking of PAN is accompanied simultaneously with the polymerization process at high energy radiation. Characterizations of the cross-linked PAN prepared at different radiation doses were investigated by FT-IR, XRD, DSC, and TGA analysis. The appearance of an IR band at 1670 cm-1 confirmed the cross-linking of PAN via nitrile groups. The original crystal lattice and the entropy of melting ΔS m did not change significantly at high radiation doses.

Low plasma ChE levels support the diagnosis of insecticides poisoning, but no significant association is present between the severity of poisoning and plasma ChE levels. Atropine should be used as soon as possible to counteract the muscarinic effects. Appropriate management and early recognition of the complications may decrease the mortality rate.

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The facile modification of pinewood sawdust, with maleic acid, to produce a sorbent aimed at metal ion adsorption, was tested via the batch adsorption of Cd(II) ions from aqueous solution. The sorbent was characterized for the pH of zero point charge (pHZPC), spectroscopic evaluation of the surface functionalization, structural and morphological features. Factors affecting adsorption behavior, such as adsorbent dose, pH of solution, contact time and Cd(II) ion concentration were investigated. Results obtained show the adsorption rate to be comparatively fast, with equilibrium achieved after 35 min. Subsequent analysis, showed Langmuirian behavior and a monolayer adsorption capacity of 180.4 mg g -1 , at pH 6; while data derived from two-parameter and three-parameter isotherm models was evaluated using non-linear regression methods, with error analysis, to determine the most appropriate model and allow prediction of optimum parameters. The Sips isotherm model proved the most appropriate in describing the experimental data obtained in the study; with a low level of heterogeneity in the adsorption sites occupied suggesting the interaction of the metal ions