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您的检索式：作者名="Weakley Andrew"
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| 1 | Dynamic failure in coal seams Implications of coal composition for bump susceptibility显示文摘As a contributing factor in the dynamic failure(bumping) of coal pillars,a bump-prone coal seam has been described as one that is ‘‘uncleated or poorly cleated,strong...that sustains high stresses.'Despite extensive research regarding engineering controls to help reduce the risk for coal bumps,there is a paucity of research related to the properties of coal itself and how those properties might contribute to the mechanics of failures. Geographic distribution of reportable dynamic failure events reveals a highly localized clustering of incidents despite widespread mining activities. This suggests that unique,contributing geologic characteristics exist within these regions that are less prevalent elsewhere. To investigate a new approach for identifying coal characteristics that might lead to bumping,a principal component analysis(PCA) was performed on 306 coal records from the Pennsylvania State Coal Sample database to determine which characteristics were most closely linked with a positive history of reportable bumping. Selected material properties from the data records for coal samples were chosen as variables for the PCA and included petrographic,elemental,and molecular properties. Results of the PCA suggest a clear correlation between low organic sulfur content and the occurrence of dynamic failure,and a secondary correlation between volatile matter and dynamic failure phenomena. The ratio of volatile matter to sulfur in the samples shows strong correlation with bump-prone regions,with a minimum threshold value of approximately 20,while correlations determined for other petrographic and elemental variables were more ambiguous. Results suggest that the composition of the coal itself is directly linked to how likely a coal is to have experienced a reportable dynamic failure event. These compositional controls are distinct from other previously established engineering and geologic criteria and represent a missing piece to the bump prediction puzzle. | Lawson Heather Weakley Andrew Miller Arthur | 2016 | International Journal of Mining Science and Technology2016，26，1： | 6 |
| 2 | Chemical effects of a solvent-limited approach to HCl-doped polyaniline anopowder synthesis显示文摘 | Hesham Ramzy Tantawy Andrew T Weakley Ericaston D | 2014 | The Journal of Physical Chemistry C2014，118，12： | 1 |
| 3 | Molecular phylogenetic analysis suggests paraphyly and early diversification of Philadelphus (Hydrangeaceae) in western North America: New insights into affinity with Carpenteria显示文摘Philadelphus (Hydrangeaceae ) 包括 60 或在东方亚洲和西方的亚洲分离地散布的更少种类。类高度在园艺被珍视,但是糟糕关于分类,种关系,和 biogeographic 历史理解。现在的学习是第一种系发生并且 Philadelphus 用的 biogeographic 分析原子并且评估分类计划并且阐明的叶绿体 DNA 标记 biogeographic 起源。我们的结果建议 Philadelphus 是有类 Carpenteria 在内嵌套的 monotypic 的一个 paraphyletic 组。三个主要的系在 PhiladelphusCarpenteria clade 被识别,强烈各由分子的数据支持了。用 Bayes 歌剧女主角方法的 Biogeographic 分析(在最新发达的粗锉实现了) 并且带着野兽标明日期的分叉时间在西方的北美洲(包括的墨西哥) 解决了起源和 Philadelphus s.l (包括的 Carpenteria ) 的早多样化在始新世。进亚洲和另外的区域在多样化、随后散布的系晚第三级或获得世界范围的分布的晚第三纪。学习增加一个另外的例子一 out of 北半球的 phylogeographic 历史上的西方的北美洲移植。 | Yue-Long GUO Andrew PAIS Alan S. WEAKLEY Qiu-Yun (Jenny) XIANG* | 2013 | Journal of Systematics and Evolution2013，51，5： | 1 |
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