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261.
鄂尔多斯盆地南部延长组有效烃源岩 总被引:3,自引:0,他引:3
在烃源岩和原油生物标志物特征精细剖析、类型划分与对比的基础上,确定鄂尔多斯盆地南部地区延长组有效烃源岩主要为长7油页岩和长7暗色泥岩,结合烃源岩的生烃潜力和测井响应特征,建立有效烃源岩的生物标志物参数、常规地球化学评价参数、测井电性参数三级识别标志,即8β(H)-升补身烷/8β(H)-补身烷<2,w(TOC)>1.6%,S1+S2>4 mg/g,IH>170 mg/g,GR>120 API,Δt>260μs/m,RT>15Ω.m,CNL>25%,并根据地化参数与电性参数之间的相关性,采用多元回归的方法建立w(TOC)及IH的测井计算公式,从而实现从有限岩心的地球化学信息到全区全井段测井信息的衔接。 相似文献
262.
贵州南部喀斯特地区非褶菌物105种,已报道了8科20属44种。本文报道该地区非褶菌物多孔菌科Polyporaceae 61种和变种,27属。其中28种为非贵州新记录。所有标本保存在贵州科学院真菌标本室。 相似文献
263.
GuoHui Zhou JingJung Wen DeJiang Cai Peng Li DongLin Xu ShuGuang Zhang 《科学通报(英文版)》2008,53(23):3677-3685
For the past several years, a novel dwarf disease has been observed on rice (Oryza sativa) in some regions of Guangdong Province and Hainan Province, southern China. Infected plants showed stunting, dark leaf and small enations on stem and leaf back. Typical Fijivirus viroplasma containing crystalline arrayed spherical virons approximately 70--75 nm in diameter and tubular structures were detected in ultrathin sections by an electron microscope in parenchyma phloem cells of the infected plants. The virus was transmitted to rice seedlings by white-backed planthoppers, Sogatella furcifera (Hemiptera: Delphacidae), collected in the diseased fields. Analysis of dsRNA extracts from infected plants revealed ten linear segments, which were similar to the electrophoretic profile of Rice black-streaked dwarf virus (RBSDV). RT-PCR with a single primer which matched to a linker sequence ligated to both 3' ends of the viral genomic dsRNAs resulted in amplification of genome segments 9 (S9) and 10 (S10) cDNA products. The complete nucleotide sequences of S9 and S10 were obtained from clones of the RT-PCR amplicon exhibited characteristic properties of Fijivirus including low GC content (34.5% and 35.6%), genus conserved 5' and 3' termini sequences and similar genome organization. Blast searches indicated that the sequences of S9 and S10 shared 68.8%--74.9% and 67.1% --77.4% nucleotide identities with those of viruses in the Fijivirus group 2, respectively. These values were similar to those among other viruses in the Fijivirus group 2 and considerably lower than those among RBSDV isolates. Phylogenetic trees based on S9 and S10 nucleotide sequences and their putative amino acid sequences showed that this virus represented a separate branch among other Fijiviruses. The virus was also detected by a nested RT-PCR assay in corn (Zea mays), barnyard grass (Echinochloa crusgalll), Juncellus serotinus and flaccidgrass (Pennisetum flaccidum) in and/or adjacent to the infected rice fields. I 相似文献