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101.
Generally, plastics and plastic films are low in moisture absorption and high in electric insulation. They are inherently easy to be charged with static and can cause a variety of static troubles. We developed a functional packaging material to solve these static problems, by using potassium ionomer. We reported good antistatic performance (e.g. short static decay time, and excellent ash test) of potassium ionomer films in a previous paper. However, a mechanism underlying the antistatic property of potassium ionomer has not yet been fully elucidated. In this study, we measured the space charge distributions of potassium ionomer using the pulsed electro‐acoustic method. As a result of the space charge measurements, we found characteristic charge distribution of potassium ionomer film. On the basis of the existence of this characteristic charge distribution, we speculate that the space electric charge distribution of a potassium ionomer film under a direct current electric field shows apparent electric charge movement. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
102.
One of the chemicals most clearly exemplifying scientific and political controversy concerning efforts to control its discharge to surface waters is phosphorus and its complexes. These materials are discharged as natural components of domestic wastewaters and include phosphorus from human waste and food waste as well as residual detergent phosphorus. Significant amounts of phosphorus also reach surface waters from non-point sources such as agricultural and urban runoff. This paper presents results of several field and laboratory investigations designed to position the impact of detergent phosphorus contributions to surface water quality. In a number of areas where legislation banned the sale of phosphorus detergents, limnological investigations were carried out to assess the impact of the ban upon receiving water quality. Field studies in natural lakes demonstrate that reductions of phosphorus in wastewaters, even up to 50%, may not substantially improve the trophic status of lakes. The consistent conclusion emerging from these studies is that the elimination of detergent phosphorus has not measurably improved lake water quality.  相似文献   
103.
Prevention of the occurrence of diabetes-specific vascular complications is the final aim of clinical islet transplantation. Pancreatic islets isolated from adult pigs may be a suitable tissue source to transplant a large number of type 1 diabetic patients. Acute cellular rejection may be finally overcome by clinically applicable protocols for tolerance induction. However, primary nonfunction of the graft, as regularly observed in the porcine islet-to-rat xenotransplantation model, may be an additional problem. In this paper, species-specific inflammatory and immunological mechanisms are discussed which prevent early porcine islet graft function in rats but not in mice.  相似文献   
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Decoded PLA (programmable logic array) has a distinct advantage over ordinary PLA, in that it can realize complex functions with smaller chip area. This paper shows that decoded PLA is particularly suitable if the function to be realized has some form of symmetry. The paper describes a new approach for d-PLA realizations using symmetries. It also describes the computer simulation which helps in the detection and use of such symmetries. Two such realizations are also described.  相似文献   
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