Irradiation solubility parameter

The radiation grafting of TFS onto various fluorine-containing base polymers, such as LDPE, ETFE, PEA, FEP, and PTFE has been accomphshed by the pre-irradiation method [105]. A proper examination of the swelling properties and solubility parameters of these polymer films in pure TFS showed that LDPE yielded the highest, and PTFE led to the lowest graft levels. This is because of the fact that the sorption of hquid in polymer depends on the affinity between the hquid and the polymer film. 

It is widely considered that the physical properties of dissolved gases affect the sonochemical efficiency. The ratio of specific heats, y = Cp/Cv, the thermal conductivity, and the solubility in water are the important parameters. The effects of dissolved gas on the reduction of Au(III) under ultrasonic irradiation are shown in Fig. 5.6 [29]. It can be seen that the changes in the concentration of Au(III) are strongly dependent on the types of dissolved gas. 

The hydroxides of berklium(III), Bk(OH)3, and califomium(III), Cf(OH)s, behave in a similar fashion [3]. In their crystalline forms, Am(OH)s and Cm(OH)3 are anhydrous (as are hydroxides of light rare-earth elements), and are hexagonal, C 6h P s/m space group, a = 6.420 and 6.391 A, c = 3.745 and 3.712 A, for Am and Cm compounds, respectively. Due to self-irradiation, the unit-cell parameters increase with time, as does the sample amorphization. In the case of " Cm(OH)3, the stmcture decomposes within 1 day, but the same process for " Am(OH)3 takes up to 4-6 months [4]. The Mossbauer spectrum of Am(OH)3 [5] is characterized by 5 = 4.6 cm/c (relative to Am02). The nuclear magnetic resonance (NMR) studies indicate that, among the TUE(III) hydroxides, the Am compound has the most covalent chemical bonds. The TUE(III) hydroxides are readily soluble in different mineral acids under these conditions, the solutions of hydrated An ions are produced. 

The irradiation experiment TRABANT is planned and executed in a trilateral cooperation with CEA and FZK. The Institute activities are concentrated on the fabrication of fuel pins to be irradiated in a TRIOX capsule in the HFR reactor at Petten. The purpose of the irradiation is to study the behaviour of the new materials under neutron irradiation in order to get information on such parameters as Pu- and MA-distribution, separation processes and solubility behaviour in nitric acid. 

If equilibrium parameters are used to describe the laser induced redistribution, a very large fraction of the dissolved impurities should be rejected at the surface. For example Kq for Te in Si is 4x10 , so that only a negligible fraction of impurities should be retained inside the sample. Instead a large amount of impurities in great excess of the maximum solid solubility limit is found after irradiation in substitutional lattice sites. 

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