We studied the trapping of positive and negative charges in the chemical structures of polymers under a high electric field using a space charge measurement system. Positive charges accumulated in low-density polyethylene (LDPE), whereas positive and negative charges accumulated in polyimide (Kapton ® ) and also in ethylene tetrafluoroethylene (ETFE) subjected to electron beam irradiation. To determine the charge-trapping sites in the chemical structures, a quantum chemical calculation was carried out using Density Function Theory (DFT) with Gaussian 09. The relationship between the energy band and the isosurface of orbital electrons at various energy levels was obtained. A threedimensional (3D) electrostatic potential distribution map was obtained for positively and negatively charged polymers to determine the relationship between a trapping site and the charge accumulation center in the 3D potential distribution map. Positive and negative charges in Kapton and ETFE films are trapped in trapping sites in chemical structures and the positive charges in an LDPE film are trapped in physical defects.

1. Phosphatase I1 is a form of phosphoprotein phosphatase originally found in rat liver extract; it has a molecular weight of 160000 by gel filtration and is highly active towards phosphorylase a. This phosphatase has been purified 1800-fold by using DEAE-cellulose (DE-52), aminohexyl-Sepharose-4B, protamine -Sepharose4B and Sephadex G-200 chromatography. Throughout the purification steps, the original molecular weight and substrate specificity of phosphatase I1 were almost perfectly preserved.2. The product of the final purification step migrated predominantly as a single protein band on non-denaturing gel electrophoresis. Sodium dodecyl sulfate gel electorphoresis revealed that the enzyme contains two types of subunit, a and p, with molecular weights of 35000 and 69000, respectively. When treated with 0.2 M 2-mercaptoethanol at -20 "C, phosphatase I1 was dissociated to release the catalytically active a subunit. The fi subunit may be catalytically inactive but interacts with the a subunit so that phosphatase I1 becomes much less susceptible than the a subunit to inactivation by ATP or pyrophosphate.

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The observation of slow-wave sustained (SW) discharge in a whistler- or helicon-wave range of frequency is made using high-frequency and very-high-frequency bands of rf. The SW discharge occurs at an extremely low rf power and plasma density, which are lower than a capacitive-coupling discharge region.