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The new genus and species Angustaeshna magnifica of Burmaeshnidae is described on the basis of a new fossil from Burmese amber. The genus Cretaeshna from the same amber is transferred from the Telephlebiidae into the Burmaeshnidae. We redefine this last family, no longer considered as the sister group of the Late Cretaceous Enigmaeshnidae, but as putative sister group of the Telephlebiidae in the Aeshnoidea. No known fossil belongs to the Telephlebiidae. 相似文献
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Viara Minkovska Bernard Peybernès Pierre Cugny Todor Nikolov 《Comptes Rendus Geoscience》2004,336(10):931-938
Within the Emerici zone–Barremense zone biostratigraphic interval, the Barremian deposits of Central Fore-Balkan (Lovech–Veliko Tarnovo shelf) consist of a succession of several formations where alternate terrigenous argillaceous/sandy-dominated facies (Kormjansko Fm., Balgarene Fm.) and carbonate-dominated (‘Urgonian’) facies (Krushevo Fm., Emen Fm.). The qualitative and, particularly, quantitative facies analysis of the carbonate successions observed along 13 detailed cross-sections and in one drill hole show the stacking of about 40 fifth-order T–R cycles induced by numerous eustatic jerks contributing to the progressive settlement of this shelf. These high-frequency cycles of about 100 000 years must be regarded as valuable correlation tools for the subsurface hydrocarbon research. To cite this article: V. Minkovska et al., C. R. Geoscience 336 (2004). 相似文献
96.
Anne Prieur Jean-François Bonnet Michel Combarnous 《Comptes Rendus Geoscience》2004,336(15):1323-1335
The role of forest ecosystems in the regulation of greenhouse effect at the global scale is developed here, from two points of view, sometimes considered as opposed: carbon storage and wood production for energy. A nomenclature is proposed to understand all the various mechanisms implied in carbon storage. A comparison is made between the effects on carbon emissions of storage alone and storage with wood fuel production. Use of wood energy is proved to be a ‘bonus’ that could optimise, in the middle and long terms, the use of fossil fuel reserves. To cite this article: A. Prieur et al., C. R. Geoscience 336 (2004). 相似文献
97.
Forty‐Nine Major and Trace Element Concentrations Measured in Soil Reference Materials NIST SRM 2586, 2587, 2709a, 2710a and 2711a Using ICP‐MS and Wavelength Dispersive‐XRF
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Harris L. Byers Lindsay J. McHenry Timothy J. Grundl 《Geostandards and Geoanalytical Research》2016,40(3):433-445
Excellent agreement was noted in the concentration of major and trace elements in five NIST (National Institute for Science and Technology) soil reference materials (NIST SRM 2586, 2587, 2709a, 2710a and 2711a) between measurement results from wavelength dispersive‐XRF and ICP‐MS from two independent laboratories, and NIST certificate of analysis and literature data. We describe the variability in concentrations of up to forty‐nine elements (plus loss on ignition) and provide values for up to twenty‐one elements previously uncharacterised by NIST in these soil RMs. The additional characterisation provided in this investigation can be utilised to reduce the measurement bias of custom calibration routines and improve the quality of control checks developed using these NIST RMs. 相似文献
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The rhagionid Lebanoleptis huangi gen. et sp. nov. is described from the Lower Cretaceous amber of Lebanon. It is characterized, illustrated, and compared with the recent and fossil genera having the same particular absence of wing vein M3. Other Mesozoic flies with similar venation and currently attributed to the Rhagionidae are briefly discussed and should be revised. 相似文献
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厦门文昌鱼遗传多样性研究 总被引:6,自引:1,他引:6
运用分子标记技术,对厦门现有文昌鱼(Branchiostoma balcheri Gray)海域(蟹口海域、南线海域、黄厝海域)文昌鱼种群进行遗传多样性研究。通过10个有效引物的RAPD反应,共扩增出238条带,其中多态性条带为121,占总扩增条带的50.84%。Nei指数法分析和UP(小俄统计分析表明:厦门3个海域文昌鱼可分为2个组。平均遗传距离为0.11。南线海域文昌鱼和黄厝海域文昌鱼的遗传距离为0.07,亲缘关系较近,聚类于同一组;蟹口海域文昌鱼与南线海域文昌鱼和黄厝海域文昌鱼的遗传距离分别为0.12和0.14,亲缘关系较远,单独为一组,结论 与3个海域的文昌鱼形态比较结果一致,出现遗传分化。Shannon遗传多样性指数统计结果表明:蟹口海域种群为0.616,南线海域种群为0.497,黄厝海域种群为0.391。厦门文昌鱼种群遗传多样性是各种群的遗传特性与该海域各种环境生态因子长期作用的结果,三元线性相关分析发现目前主要生态因素是底质和海水深度,3个海域中以蟹口海域的自然环境最为优越(其底质为中粗沙或粗中沙、水深8—15m)。根据以上研究结果,本文提出了厦门海域文昌鱼资源的保护建议。 相似文献
100.
异枝凹顶藻Laurencia intermedia Yamada广泛地分布于东亚西太平洋沿岸的中国、朝鲜半岛(Nam et al. , 1984)及日本(Yoshida et al. , 1998)。在东南亚的菲律宾(Silva et al., 1987),太平洋的斐济岛(NYeurt et al., 1996),东非、印度次大陆及印度洋的斯里兰卡、肯尼亚、坦桑尼亚及Réunion (Silva et al., 1996),以及西非的利比里亚、象牙海岸及加纳(Law son et al., 1987)等地均有报道。
Howe(1934)最早报道了中国的异枝凹顶藻。1962年,曾呈奎、张峻甫在“黄海西部沿岸海藻区系的温度性质”一文中也提到了该藻。1983年, 曾呈奎等在《Common seaweeds of China》中报道了黄海沿岸的异枝凹顶藻。1983年, 杭金欣等在《浙江海藻原色图谱》报道了浙江嵊山、渔山和南凫岛的异枝凹顶藻。1988年,张峻甫等也再次对该藻进行了报道。2000年,黄淑芳报道了台湾的异枝凹顶藻。 相似文献