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and other foreign matter invasion. Key words: railway rail recognition; Radon transform; Bresenham algorithms; straight line detection; foreign matter invasion 确保列车运行安全是铁路运输永恒的主题,然而,我国地理环境复杂,气候变化多样,特别......
; 开放科学(资源服务)标识码(OSID) 文章编号:1672-7207(2020)08-2049-12 Geochemical characteristics and organic matter enrichment mechanism of the Lower Cambrian Niutitang formation... and controlling factors of organic matter(OM) enrichment, 32 core samples of Niutitang formation from well AY-1 in Central Hunan were selected for geochemical tests such as total carbon mass fraction of TOC......
; carbonaceous fibers; chemical composition; apparent crystallinity degree; volume electrical resistivity; surface electrical resistivity; [全文内容正在添加中] ......
was then investigated via transient experiments. Key words:optics; condensed matter physics; energy transfer; luminescence; LiKGdF5∶Er3+,Tb3+; rare earths; [全文内容正在添加中] ......
seamounts; Co-rich crusts; molecular marker; carbon isotopes of organic matter δ13C; paleoceanography 以往的古海洋学研究多以海洋湖泊沉积物岩芯为对象,但由于其沉积速率快(通常认为比结壳生长速率快千倍),导致研究的时间尺度往往较短,而要获得时间尺度大的沉积物岩芯,其技术及采样成本均很高.富钴结壳与沉积物...-yong, FANG Nian-qiao, et al. Carbon isotopic composition of organic matter in Co-rich ferromanganese crust and its implication for paleoceanography[J]. Earth Science-Journal of China University......
水环境质量评价中的几种方法初征1(1.北京市北京矿冶研究总院 )摘 要:通过理论阐述及实例分析,对指数法,模糊综合评判法,灰色聚类法和物元分析法等四种常用的水环境质量评价方法进行比较分析,并对各种评价方法的优点和不足做出总结.结果表明,物元分析法的评价结果更趋合理.关键词:环境工程； 水环境质量评价； 指数法； 模糊综合评判法； 灰色聚类法； 物元分析法......
coals and one anthracite were used in this study.On the basis of the similar volatile matter contents of the four bituminous coals, the effects of ash in coal on the microstructure, carbonaceous... spectroscopy and X-ray diffraction pattern showed that as the ash content increased, the degree of graphitization of coal carbonaceous structure gradually decreased.The combustibility of the four bituminous......
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Heidelberg 2016 Abstract: In order to investigate the differences of macropores vertical distribution under different surface plants, and to assess the influences of root systems, organic matter and texture... different plants is significant. Root systems have significant effects on macropore flow paths distribution and the effect become more pronounced as the diameter of roots become larger. Organic matter......
. Concentrations of REEs in unfiltered water are high and they mainly resided on suspended matter. Distribution patterns of the dissolved and susp ended light REEs vary reversely with the atomic number. Concentrations of REEs in the sediments and suspended matter are lower than those in natural rivers, and concentrations of REEs in the suspended matter are much lower than those in the sediments. Distribution......
