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This paper reports recent results in a continuing ESR study of free radicals in electrical trees in polyethylene (PE). Data pertaining to three different kinds of PE are presented: commerc i al cable material (XLPE), and two low density materials (LDPE), one r elatively impure, the other of high purity (HPPE). It is found that the saturation behavior of the absorption lines is particularly useful for distinguishing different physical situations. On the basis of these observations, a preliminary classification with respect to the degree of carbonisation of char produced in different kinds of trees is proposed.

The fuel cell is a renewable technology which utilizes the hydrogen fuel via oxidation to generate electricity. The development of the technology is being focused on the most effective configurations of these processes to balance availability, efficiency and capacity. A meta-study has been conducted with the aim to analyze fuel cell performance was analysed of different materials such as; Solid Oxide fuel cells, Nafion and Peresulfuric acid under a series of variables: current density, temperature, pressure, membrane thickness and humidity. The reaction kinetics at high temperatures allow for greater hydrogen and oxygen permeability and solubility but are limited by proton conductivity of membrane at high temperature. From meta-study outcome, the largest improvement in current density is achieved by improving cathode polarity and membrane permeability. Optimizing H+ ion concentration is done by increasing humidity through increased pressure.