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您的检索式：作者名="Md. Mahbubul ALAM"
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| 1 | Geochemical characteristics of Holocene sediments from Chuadanga district, Bangladesh: Implications for weathering, climate, redox conditions, provenance and tectonic setting显示文摘The present research deals with the geochemical characteristics of the Holocene sediments from Alamdanga area, Chuadanga district, Bangladesh. Main goals of the study are to delineate source rock characteristics, degree of chemical weathering and sorting processes and behavior of redox conditions during deposition of the sediments. Geochemical characteristics of the sediments show comparatively a wide variation in accordance with stratigraphy in their major element contents(e.g. Si O2 69.46–82.13, Al2O3 2.28–8.88 in wt%), reflecting the distinctive provenance and in part an unstable period in terms of tectonic activity. Geochemical classification of the sediments shows mostly sub-arkose with few sub-litharenites. Some major and trace elements display comprehensible correlation with Al2O3 confirming their possible hydraulic fractionation. The chemical index of alteration(CIA*), W* index, index of compositional variability(ICV), plagioclase index of alteration(PIA*) values and the ratio of Si O2/Al2O3, suggest low degrees of chemical weathering in the source areas as well as immature to moderately mature the sediments. The sediments suggest semi-arid climatic trends within oxic deltaic depositional conditions during the Holocene, at 3–12 ka. Whole rock geochemistry and discrimination diagrams demonstrate the continental signature derivatives, which might have been derived from the felsic to intermediate igneous rocks(granitic plutonic rocks) as well as from quartzose sedimentary/metamorphic provenance. These typical sources are present in a vast region of the Himalayan belt and catchment areas of Ganges. The tectonic setting of the sediments demarcates typically passive margin with slightly continental arc system. | Ismail Hossain Krisna Kanta Roy Pradip Kumar Biswas Mahbubul Alam Md. Moniruzzaman Farah Deeba | 2014 | Chinese Journal Of Geochemistry2014，33，4： | 3 |
| 2 | The Effect of Non-Equilibrium Condensation on Supersonic Air Flows over Rectangular Cavities显示文摘数字模拟在开的、矩形的洞上为超声的二维的流动被执行了(length-to-depth 比率是 L/D = 1.0 和 3.0 ) 数以便为流动马赫在洞附近在超声的内部流动上调查潮湿的空气的非平衡冷凝作用的效果 1.83 在洞入口。在现在的计算调查,压缩流动被潮湿的空气的扩大在一张 Laval 嘴生产。计算结果证明没有冷凝作用,在上游的旅行压缩波浪变得比那些弱。因而,更弱的压缩波浪不能强烈使 shear 层激动,没有冷凝作用,在洞的摆动的振幅变得比那些小。在 L/D = 的情况下的非平衡冷凝作用的出现 1.0 强烈与 L/D = 相比在洞影响了摆动的振幅和频率 3.0。 | Miah MD. Ashraful ALAM Md. Mahbubul ALAM Shigeru MATSUO Kenbu TERAMOTO Toshiaki SETOGUCHI Heuy Dong KIM Shen YU | 2007 | Journal of Thermal Science2007，16，1： | 0 |
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