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排序方式: 共有287条查询结果,搜索用时 218 毫秒
1.
川东北三叠系飞仙关组鲕滩气藏有利储集层的形成与分布 总被引:19,自引:5,他引:14
川东北地区三叠系飞仙关组鲕滩气藏是近年四川盆地碳酸盐岩天然气勘探取得重大突破的领域,目前在中国石油探区内已发现罗家寨、渡口河、铁山坡等大中型气藏。对鲕滩气藏白云岩储集层进行岩心观察、显微薄片分析,并进行微量元素、流体包裹体、X衍射、阴极发光及电子探针等分析,结果表明,白云岩化和多期溶蚀是形成优质白云岩储集层的关键因素,混合云化与埋藏云化的叠加作用是形成孔隙性白云岩储集层的基本条件。飞仙关组鲕滩气藏储集层经历了4期溶蚀作用,即同生期溶蚀作用、浅埋期溶蚀作用、深埋期溶蚀作用和抬升期溶蚀作用,形成优质白云岩储集层的主要溶蚀作用是浅埋期和深埋期的溶蚀作用。优质白云岩储集层主要分布在台缘鲕粒滩相带,纵向与亮晶鲕粒灰岩呈韵律性互层,横向主要分布在鲕粒滩坝靠近漏湖-潮坪一侧。 相似文献
2.
Selection of strategies that help reduce riverine inputs requires numerical models that accurately quantify hydrologic processes. While numerous models exist, information on how to evaluate and select the most robust models is limited. Toward this end, we developed a comprehensive approach that helps evaluate watershed models in their ability to simulate flow regimes critical to downstream ecosystem services. We demonstrated the method using the Soil and Water Assessment Tool (SWAT), the Hydrological Simulation Program–FORTRAN (HSPF) model, and Distributed Large Basin Runoff Model (DLBRM) applied to the Maumee River Basin (USA). The approach helped in identifying that each model simulated flows within acceptable ranges. However, each was limited in its ability to simulate flows triggered by extreme weather events, owing to algorithms not being optimized for such events and mismatched physiographic watershed conditions. Ultimately, we found HSPF to best predict river flow, whereas SWAT offered the most flexibility for evaluating agricultural management practices. 相似文献
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Waste organics conversion to algal lipid is environmentally friendly and it promotes sustainability. Achieving high-lipid content in cells is crucial to the economic feasibility of algal lipid production and collection. Here, a phagotrophic microalga Ochromonas danica was grown on waste ketchup and then stimulated to accumulate high-lipid content using glycerol and acetate. Individually, glycerol and acetate could increase lipid synthesis. Sequential glycerol-then-acetate addition was more effective; for an O. danica culture with 0.25 g L−1 cells, the intracellular lipid content was increased to 70–80% (w/w) in 6–12 hours. However, acetate added at >1 g L−1 damaged cells. For high-density (25 g L−1) fermentations, glycerol and acetate addition strategies were evaluated to overcome this inhibition. Results indicated that glycerol could be added in batches or continuously as long as the amount was sufficient to satisfy the glycerol consumption rate of 6 mg (g cells-hour)−1 while acetic acid needed to be added continuously, optimal at a rate of 0.27–0.30 g hour−1 or 12–14 mg (g cells-hour)−1. Intracellular lipid content could reach 70–80% after 2-day supplementation of glycerol and acetic acid. The methods of glycerol/acetate additions developed here enhance algal lipid production and enable effective conversion of organic wastes to algal lipids as sustainable bioproducts. 相似文献
6.
Dwi Susilaningsih Khuzaemah Delicia Yunita Rahman Hiroshi Sekiguchi 《International Journal of Hydrogen Energy》2014
The screening for finding the lipid producer of indigenous Indonesian tropical microalgae that obtained from peat-land at Riau, Sumatra and seashore at Lombok has carried out. Preliminary screening was done by selection on faster growing algae from 44 (forty-four) isolates. 10 (ten) isolates were chosen for further analysis. Out of 10 selected isolates shows that five isolates have indication rapid growth and high content of lipid, furthermore those chose isolates were observed comprehensively, namely LIPI11-2-Al005, LIPI11-2-Al010, LIPI11-2-Al015, LIPI11-2-Al018, and LIPI11-2-Al019. The microalgae are belong to the eukaryotic microalgae and its seem to be closed to Chlorophytes that has cell nuclear with an envelope, light green chloroplast, thick cell wall, round and elongated cell features. Cultivation of the microalgae in laboratory condition (1 L) has shown that lipid content was about 20–35% base in cell dry weight. The highest lipid content was found in the isolate LIPI11-2-Al018 of 30.74% per dry weight cell. LIPI11-2-A1018 therefore was test for scale up cultivation reach the culture volume of 5 L in the cylindrical photobioreactor, and expected to be source of triglycerides and lipids for biodiesel ingredient. 相似文献
7.
针对高磷鲕状赤铁矿中有价组元铁与杂质元素磷、硅、铝的分离难题,提出了低温选择性金属化还原—磁选—熔分处理新工艺,添加复合促进剂强化还原并促进金属铁微粒迁移、聚集、长大。研究了焙烧温度、促进剂用量、煤量、焙烧时间等条件对焙砂磨矿磁选后精矿铁品位、铁回收率及脱杂效果的影响。结果表明,添加剂对铁的富集及脱杂影响显著。优化的焙烧工艺条件下,原矿加入6%促进剂、25%的煤,975℃下恒温焙烧150 min,焙砂中铁主要以单质铁呈棒条状、蠕虫状产出,利于磨矿解离;磷仍主要以磷灰石存在;焙砂经磨矿—磁选,可获得含Fe 86.77%、P0.20%、Al_2O_3 1.81%、SiO_2 3.86%的精矿类海绵铁粉,Fe回收率88%;类海绵铁粉在1 550℃下熔分,可以得到含磷小于0.01%、含铁大于99%的优质铁水,全流程Fe回收率85%,杂质磷、硅、铝脱除率99%,实现了铁的高效回收和铁与磷、硅、铝组元的深度分离。 相似文献
8.
四川龙岗西区碳酸盐岩礁、滩体识别技术 总被引:1,自引:0,他引:1
近年来先后在普光、龙岗地区礁、滩体油气勘探中获得的重大发现,揭示开江—梁平海槽区礁、滩体具有良好的油气勘探前景。本文基于叠前偏移地震资料,结合钻、测井勘探成果数据,在沉积、构造分析的基础上,应用层拉平、体曲率、层序地层学解释及叠前反演等技术,在龙岗西区开展二叠系长兴组生物礁和三叠系飞仙关组鲕滩储层的预测和描述,取得了较好成效,并初步形成一套礁、滩体识别的系列技术及配套流程。 相似文献
9.
The current paper investigates the role of barley straw conditioning on inhibiting the alga Scenedesmus. Fresh, pre-rotted and white rot fungi (WRF) augmented straw was tested in a series of chemostat experiments over 15 weeks. All three systems were effective at inhibiting the alga with differences observed in the lag time before inhibition occurred and the rate of alga decline. Lag times of 8, 4 and 1 week(s) were recorded for the fresh, rotted and fungi-treated straws, respectively, with a maximum inhibition rate of >7 × 104 cells week−1 observed for the fungi pre-treated system. Overall, the results indicate that pre-treatment is a viable method to enable barley straw to be used in a more reactive manner. Explanation is postulated that during pre-treatment no alternative sources of nitrogen are available, thereby leading to greater bacterial decomposition of straw lignin to release inhibitory substances. The principle of utilising an engineered pre-treatment by inoculating barley straw with WRF to enhance the impact of the straw on algal inhibition has been clearly demonstrated. Further work is required to understand how the straw pre-treatment stage can be reduced to minimise its duration while maximising the inhibitory effect of adding barley straw. 相似文献
10.
Formation of carbonaceous and nitrogenous disinfection by-products from the chlorination of Microcystis aeruginosa 总被引:1,自引:0,他引:1
Formation of carbonaceous disinfection by-products (C-DBPs), including trihalomethanes (THMs), haloacetic acids (HAAs), haloketones (HKs), chloral hydrate (CH), and nitrogenous disinfection by-products (N-DBPs), including haloacetonitriles (HANs) and trichloronitromethane (TCNM) from chlorination of Microcystis aeruginosa, a blue-green algae, under different conditions was investigated. Factors evaluated include contact time, chlorine dosages, pH, temperature, ammonia concentrations and algae growth stages. Increased reaction time, chlorine dosage and temperature improved the formation of the relatively stable C-DBPs (e.g., THM, HAA, and CH) and TCNM. Formation of dichloroacetonitrile (DCAN) followed an increasing and then decreasing pattern with prolonged reaction time and increased chlorine dosages. pH affected DBP formation differently, with THM increasing, HKs decreasing, and other DBPs having maximum concentrations at certain pH values. The addition of ammonia significantly reduced the formation of most DBPs, but TCNM formation was not affected and 1,1-dichloropropanone (1,1-DCP) formation was higher with the addition of ammonia. Most DBPs increased as the growth period of algal cells increased. Chlorination of algal cells of higher organic nitrogen content generated higher concentrations of N-DBPs (e.g., HANs and TCNM) and CH, comparable DCAA concentration but much lower concentrations of other C-DBPs (e.g., THM, TCAA and HKs) than did natural organic matter (NOM). 相似文献