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Mossbauer absorption spectra in a natural chromite from Shanxi province of China were measured, covering a temperature range from 12 K to 800 K. Each spectrum at low temperature can be fitted to three doublets: the first two are attributed to tetrahedral T-site Fe ions and the third one to octahedral M-site Fe ions. Such assignment was confirmed by the detailed analyses of the temperature dependent centre shift and other parameters. As a main result, our data strongly supported the ordered distribution with Fe2+ in T-site and Fe3+ in M-site for chromite studied. No evidence for electron hopping processes was detected. 相似文献
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本文主要讲述了土建施工企业向装饰方向发展的必要性。土建工程施工已进入微利时期,将土建与装饰工程同时承包给一家公司,是市场需要的一种趋势。 相似文献
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