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51.
混合原油的地球化学特征及成藏贡献率 总被引:1,自引:0,他引:1
含油气盆地中存在混合原油的现象非常普遍,按照形成条件可区分出4种不同的混合类型.地球化学研究表明不同有机相原油混合后体现各自母源的生物标志化合物组合特征;生物降解原油与正常原油混合后具有完整的饱和烃谱峰,同时还反映生物降解特点;不同成熟度的原油混合后既可检出热稳定性低的化合物,部分成熟度参数还可指示成熟特征;高成熟天然气与原油混合后,往往会使不同组分段的成熟度产生明显变化.特殊化合物绝对浓度定量法、生物标志化合物参数法、碳同位素法和拟合图版法是常见的定量成藏贡献率方法.针对混合原油地球化学识别和贡献率定量中的局限性,提出了利用指纹技术进行优化的思路. 相似文献
52.
Rita P. Vasconcelos Patrick Reis-Santos Susanne Tanner Anabela Maia Christopher Latkoczy Detlef Günther Maria José Costa Henrique Cabral 《Estuarine, Coastal and Shelf Science》2008
Connectivity is a critical property of marine populations, particularly for species with segregated juvenile and adult habitats. Knowledge of this link is fundamental in understanding population structure and dynamics. Young adults of commercially important fish species Solea solea, Solea senegalensis, Platichthys flesus, Diplodus vulgaris and Dicentrarchus labrax were sampled off the Portuguese coast in order to establish preliminary evidence of estuarine nursery origins through otolith elemental fingerprints. Concentrations of Li, Na, Mg, K, Mn, Cu, Zn, Sr, Ba and Pb in the otolith section corresponding to juvenile's nursery life period were determined through laser ablation inductively coupled plasma mass spectrometry. Element: Ca ratios in coastal fish differed significantly amongst collection areas, except for Platichthys flesus, and were compared with the elemental fingerprints previously defined for age 0 juveniles in the main estuarine nurseries of the Portuguese coast. Identification of nursery estuaries was achieved for four of the species. Assigned nursery origins varied amongst species and differences in the spatial scale of fish dispersal were also found. Diplodus vulgaris was not reliably assigned to any of the defined nurseries. Overall, results give evidence of the applicability of estuarine habitat tags in future assessments of estuarine nursery role. Research developments on the links between juvenile and adult habitats should contribute for the integrated management and conservation of nurseries and coastal stocks. 相似文献
53.
基于JFD框架,利用基于选择性内容加密的加解密策略提高加密安全性,以及基于结构失真度选择指纹嵌入区域,以降低指纹嵌入对图像质量的影响,为此提出了一种新的指纹生成控制方法,使指纹图像具有良好的抗合谋攻击性。实验结果证明了本文方案的有效性。 相似文献
54.
指纹方向场真实地反映了指纹图像中本质的纹理特征,包括指纹的基本形状、结构和走势。方向场图像在局部区域表现相对一致,而在全局范围则表现出较大的差异。基于方向场对指纹图像进行分区,可以提供一种有用的辅助性全局特征。本文提出了一种指纹图像快速分区方法,并结合一种基于局部描述子的指纹图像匹配算法给出了其应用实例。在FVC2004DB1数据集上设计了实验,结果表明,这种分区方法能有效地提高识别率,同时缩短处理时间。 相似文献
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56.
Hans‐Eike Gäbler Frank Melcher Torsten Graupner Andreas Bahr Maria A. Sitnikova Friedhelm Henjes‐Kunst Thomas Oberthür Helene Brätz Axel Gerdes 《Geostandards and Geoanalytical Research》2011,35(4):431-448
Coltan (the African trade name for columbite‐tantalite, a tantalum ore) is one of several raw materials that finance the civil wars in the eastern provinces of the Democratic Republic of the Congo. To improve the transparency along the tantalum trade chain, a ‘certificate of origin’ for so‐called ‘conflict minerals’ has been recommended by the United Nations. Accordingly, the German Federal Institute for Geosciences and Natural Resources (BGR) has developed an analytical fingerprint procedure for coltan. Mineral formation age, modal mineralogy and chemical composition are important fingerprint parameters. The original workflow to obtain these parameters was streamlined and is now based on mineral liberation analysis and LA‐ICP‐MS. The use of an ICP‐MS instrument with a detector system covering an extended linear dynamic range and the application of an internal standard‐independent calibration strategy allowed data for major and trace element determination and mineral formation age estimates to be obtained simultaneously. The analytical results of this new approach were compared with analytical techniques of the original workflow and showed excellent agreement in terms of mineralogical and chemical characterisation and mineral formation age of coltan samples. Within a test, samples of different origin were allocated correctly and simple, binary mixtures were also identified successfully. 相似文献
57.
Thierry Pérez Julijana Ivanisevic Maude Dubois Laura Pedel Olivier P. Thomas Daria Tokina Alexander V. Ereskovsky 《Marine Ecology》2011,32(2):174-187
A new homoscleromorph sponge species was observed for the first time in 2002 along the coast of Provence (France) and since then, several investigations have been implemented. The new homoscleromorph species is devoid of skeleton and it is thus related to the Oscarella genus. Oscarella balibaloi sp. nov. has been found in several littoral submarine caves of the Western Mediterranean Sea (France and Spain). After several years of monitoring, we show that this sponge is becoming abundant in several locations. The species has a peculiar habit, often overgrowing massive sponges, gorgonians or some erected bryozoans. Oscarella balibaloi sp. nov. is thinly encrusting, with an irregular morphology, lobate surface, and soft and very slimy consistency. Its color is white to orange. At the cytological level, this new species is characterized by three distinct types of cells with inclusions in its mesohyl: one with vacuoles and the others with paracrystalline inclusions. The reproduction pattern is very similar to other Oscarella species. We also present a specific metabolic fingerprint and compare it to that of other Mediterranean Oscarella species. 相似文献
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59.
基于位置服务给人们的生活带来极大的便利,而目前定位系统特别是室内定位普遍依赖于无线网络信号.很多情况下,用户有位置隐私保护的需求,然而,在目前的大数据时代,基于网络的室内定位服务要求用户将个人位置信息实时提供给服务提供商,这导致用户隐私的泄露.如何有效实现室内的基于位置服务,并且保护用户的个人位置信息就成了大数据时代的一个关键问题.本文介绍了一种面向位置数据隐私保护的离线地磁定位模型,利用加速度传感器和微机电磁力计检测行人步态和地球磁场来实现室内定位.本模型利用加速度计检测行人的步态信息,配合磁力计检测的磁场信息与指纹地图进行匹配,实现了室内定位需求的同时又解决了用户位置信息泄露的问题,为大数据时代如何保护用户的位置信息提供了一个有效的解决办法. 相似文献
60.
应用PCR-DGGE指纹技术分析高温季节仿刺参养殖水环境中菌群多样性 总被引:3,自引:0,他引:3
采用16S rDNA的PCR-DGGE基因指纹技术,于6~9月间,对辽宁普兰店湾2个相邻的刺参养殖池塘进行了养殖水环境中菌群多样性的分析,首先用2216E固体培养基对仿刺参养殖水环境中的细菌总数进行统计,再采用PCR-DGGE指纹技术分析菌群多样性。结果表明,池塘水环境中较高水平的细菌数,且9月为6月的3倍;高温季节刺参养殖水环境中细菌种群较为丰富,其中大多数属于变形菌门;6~9月份样品具有一致的优势菌群,分别为Pseudomonas sp.,Uncul-tureddelta bacterium,Ostreococcus sp.以及Unculturedalpha proteobacterium。同时发现,同一时间采集的样品,有一定的菌群相似性,并在聚类分析图中分别成簇,检测样品的细菌多样性指数在1.7至2.5之间。 相似文献