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In organic-rich gas shales, clay minerals and organic matter (OM) have significant influences on the origin, preservation, and production of shale gas. Because of the substantial role of nanoscale pores in the generation, storage, and seepage of shale gas, we examined the effects of clay minerals and OM on nanoscale pore distribution characteristics in Lower Paleozoic shale gas reservoirs. Using the Niutitang and Longmaxi shales as examples, we determined the effects of clay minerals and OM on pores through sedimentation experiments. Field emission–scanning electron microscopy combined with low-pressure N2 adsorption of the samples before and after sedimentation showed significant differences in pore location and pore size distribution between the Niutitang and Longmaxi shales. Nanoscale pores mostly existed in OM in the Longmaxi shale and in clay minerals or OM–clay composites in the Niutitang shale. The distribution differences were attributed largely to variability in thermal evolution and tectonic development and might account for the difference in gas-bearing capacity between the Niutitang and Longmaxi reservoirs. In the nanoscale range, mesopores accounted for 61–76% of total nanoscale pore volume. Considerably developed nanoscale pores in OM were distributed in a broad size range in the Longmaxi shale, which led to good pore connectivity and gas production. Numerous narrow pores (i.e., pores?<?20 nm) in OM–clay composites were found in the Niutitang shale, and might account for this shale’s poor pore connectivity and low gas production efficiency. Enhancing the connectivity of the mesopores (especially pores?<?20 nm and those developed in OM–clay composites) might be the key to improving development of the Niutitang shale. The findings provide new insight into the formation and evolutionary mechanism of nanoscale pores developed in OM and clay minerals.  相似文献   
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As the two important components of shale, organic matter(OM) and clay minerals are usually thought to strongly influence the hydrocarbon generation, enrichment and exploitation. The evolution process of OM and clay minerals as well as their interrelationship over a wide range of thermal maturities are not completely clear. Taking Yanchang(T_3y), Longmaxi(S_1l) and Niutitang(?_1n) shales as examples, we have studied the microstructure characteristics of OM and clay minerals in shales with different thermal maturities. The effects of clay minerals and OM on pores were reinforced through sedimentation experiments. Using a combination of field emission scanning electron microscopy(FESEM) and low-pressure N_2 adsorption, we investigated the microstructure differences among the three shales. The results showed that both OM and clay minerals have strong effects on pores, and small mesopore(2–20 nm) is the dominant pore component for all three samples. However, the differences between the three samples are embodied in the distribution of pore size and the location. For the T_3y shale, clay minerals are loosely arranged and develop large amounts of pores, and fine OM grains often fill in intergranular minerals or fractures. Widespread OM pores distribute irregularly in S_1l shale, and most of the pores are elliptical and nondirectional. The ?_1n shale is characterized by the preferred orientational OM-clay aggregates, and lots of pores in the composites are in the mesopore range, suggesting that over maturity lead to the collapse and compaction of pores under huge pressure of strata. The results of the current research imply that with increasing thermal maturity, OM pores are absent at low maturity(T_3y), are maximized at high maturity(S_1l) and are destroyed or compacted at over-mature stage(?_1n). Meanwhile, clay minerals have gone through mineral transformation and orientational evolution. The interaction of the two processes makes a significant difference to the microstructure evolution of OM and clay minerals in shale, and the findings provide scientific foundation in better understanding diagenetic evolution and hydrocarbon generation of shale.  相似文献   
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Oyster peptides were produced from Crassostrea hongkongensis and used as a new protein source for the preparation of an oyster peptide-based enteral nutrition formula (OPENF). Reserpine-induced malabsorption mice and cyclophosphamide-induced immunosuppression mice were used in this study. OPENF powder is light yellow green and has a protein-fat-carbohydrate ratio of 16:9:75 with good solubility in water. A pilot study investigating immune functional impacts of the OPENF on mice show that the OPENF enhanced spleen lymphocyte proliferation and the activity of natural killer (NK) cells in BALB/c mice. Furthermore, OPENF can improve intestinal absorption, increase food utilization ratio, and maintain the normal physiological function of mice. These results suggest that oyster peptides could serve as a new protein source for use in enteral nutrition formula, but more importantly, also indicate that OPENF has an immunostimulating effect in mice.  相似文献   
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临朐县结合当地山多地少,土地后备资源严重不足的县情实际,不断创新措施,立足"增量指标保重点,一般项目靠挖潜",围绕低效闲置土地、储备未供土地、旧城改造和迁村并点以及让企业向园区集中,最大限度提高企业集中度与土地产出率等方面,千方百计盘活挖潜存量土地,努力拓展土地利用空间,破解土地制约瓶颈。同时,注重依法科学管理,严把用地预审、审批和批后监管等环节,使节约集约用地取得了明显成效,保障了当地经济健康发展。  相似文献   
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临朐县结合当地山多地少,土地后备资源严重不足的县情实际,不断创新措施,立足"增量指标保重点,一般项目靠挖潜",围绕低效闲置土地、储备未供土地、旧城改造和迁村并点以及让企业向园区集中,最大限度提高企业集中度与土地产出率等方面,千方百计盘活挖潜存量土地,努力拓展土地利用空间,破解土地制约瓶颈。同时,注重依法科学管理,严把用地预审、审批和批后监管等环节,使节约集约用地取得了明显成效,保障了当地经济健康发展。  相似文献   
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海洋科学是一门依赖于观测的学科, 而卫星是海洋研究的重要观测平台之一, 海洋卫星数据在海洋科学研究中具有重要的意义。21世纪初以来, 我国陆续发射了多颗专门用于海洋观测的卫星, 初步拥有自主海洋卫星全球观测网络。本文针对国内外海洋卫星资源基本情况, 总结了我国海洋卫星数据应用发展现状, 特别是海洋卫星数据接收、处理、管理、应用等方面的情况, 并分析、探讨了我国海洋科学研究对卫星数据的需求, 以及我国海洋卫星数据科学应用存在的问题和发展策略。  相似文献   
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International Journal of Earth Sciences - Development of fan deltas alongside intrabasinal structural highs has been overlooked compared to those forming on basin margins. However, these fan deltas...  相似文献   
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为了减少动态时程法的计算开销,根据地震时程记录的能量在时间-频率域内主要集中在特定时间段和低频分量中的特点,用离散小波变换,变采样率重构时程记录,以达到在时程计算时减少积分步数,节约计算时间的目的。通过有限元数值实验,表明该法可有效缩短计算时间,同时计算误差不超过5%,在工程范围内可以接受。  相似文献   
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海洋生物质能研究进展及其发展战略思考   总被引:3,自引:0,他引:3  
生物质能的研究与开发的目的是解决化石资源短缺和温室气体排放等全球性问题。利用油料作物生产生物柴油和利用淀粉作物生产燃料乙醇是当前生物质能产业化开发的重要内容,其原料来源主要依赖农作物,从而导致了生物质能开发与粮食、耕地和水资源竞争的局面。海洋生物质能的开发和利用为解决上述问题提供了一条可能有效的出路。介绍了海洋生物质能的国内外研究进展,分析了有关国家战略需求和关键科学问题,提出了我国发展海洋生物质能的战略思考和下一步的研究重点。  相似文献   
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