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The photocatalytic degradation performance of photocatalysts TiO2 supported on 13-X, Na-Y, 4A zeolites with different loading content was evaluated using the photocatalytic oxidation of dyes direct fast scarlet 4BS and acid red 3B in aqueous medium. The results showed that the best reaction dosage of TiO2-zeolite catalysts is about 2 g/l and the photocatalytic kinetics follows first order for all supported catalysts. The photocatalytic activity order of the three series catalysts is 13X type >Y type >4A type. The physical state of titanium dioxide on the supports is evaluated by X-ray photoelectron spectra (XPS), powder X-ray diffraction (XRD), BET, and FTIR. (C) 2000 Elsevier Science Ltd. All rights reserved.

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文冠果(Xanthoceras sorbifolia Bunge)是我国北方特有的木本油料树种,已被列为生物质能源树种之一。现阶段产量低是限制其发展的重要因素。结合目前文冠果生产发展的实际需要,有必要通过实践探讨出一套经济、简单易行的栽培措施,指导文冠果的高产优质栽培管理。本文以内蒙古翁牛特旗文冠果经济林场内40年生文冠果树为研究对象,对文冠果生物学、生态学特性进行定位观测和试验,研究了文冠果物候与积温的关系;野外布置不同管理措施的正交试验设计,测定了不同管理措施下文冠果产量和年生长周期内叶片矿质元素(N、P、K、Mg、Fe、Zn、Cu、Mn)的含量变化趋势,并对数据进行了分析。初步确定了文冠果物候与矿质养分动态变化、栽培管理措施与产量以及叶片养分含量之间的关系,为提高文冠果的产量、制定合理栽培管理措施提供一定理论依据,也为文冠果的进一步开发利用打下基础。 主要结论: 1.文冠果年生长周期内物候变化与积温呈显著对数函数关系,可以预测文冠果年生长发育期有效积温的理论值,也可以根据实际有效积温预测文冠果物候变化进程; 2.文冠果叶片中矿质元素变化与物候期有密切联系,大量元素间存在协同关系,水肥管理对叶片中矿质元素的变化有很大影响; 3.施肥和浇水均可提高文冠果果实产量,水肥耦合措施提高产量尤为显著:与对照相比,5月初一次浇水、施肥270g/株可使产量提高303%。

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