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The present study deals with the evaluation of environmental/ecological perceptions of secondary school pupils. It has two major objectives. Firstly, to administer a measurement instrument to explore ecological/environmental perceptions for a sample of approximately 900 Irish secondary school pupils aged between 12 and 16 years. The operation and use of three subscales, environmental behaviour, utilization of nature and consideration for conservation, was based on a previous study undertaken in Bavaria, but its structure, dimensionality and reliability was further assessed using psychometric procedures. Secondly, the study monitored the differences in these dimensions between Irish and Bavarian pupils. Common items within the subscale structure were selected from both samples to form a truncated item selection and to function subsequently as the basis for the final factor analysis applied to the combined Irish–Bavarian sample. Comparisons on this basis indicated substantial differences in attitudes and environmental behaviour between pupils from both regions: the Irish sample favoured less conservational values, but more patronage for the utilization of nature and it revealed less willingness to take and plan action in individual environmental behaviour. In addition, the Irish sample disclosed a significantly greater gender difference in the two subscales.  相似文献   
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We report the development of a novel simple experimental method which allows the comparison of new photosensitizers based on their production of reactive oxygen species. A high-performance liquid chromatography (HPLC) assay permits the monitoring of several substances (sensitizer, reactant and oxidized end product) simultaneously on a single chromatogram. Photoreactions were monitored throughout their course by the HPLC assay surveying the sensitizers' efficiency of singlet oxygen production by the oxidative decomposition of luminol. Several photosensitizers were tested: Rose Bengal, Methylene Blue, Protoporphyrin IX, Photosan III, Photofrin, Hypericin and Pseudohypericin. Additionally, photoreactions were monitored by a standard pO2 detection system. The measurements of the two detection methods were strongly correlated. Rose Bengal proved to be the most efficient photosensitizer, clearly decreasing the luminol concentration and causing a corresponding increase in aminophthalic acid. Our experiments show that when factors necessary for photochemical reactions are absent or are blocked (antioxidants), no reaction can be detected.  相似文献   
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