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岷江上游某水电站工程边坡软岩的崩解特性研究 总被引：2，自引：0，他引：2
工程边坡内软岩分布较广,可区分为泥化夹层、煤、炭质页岩、泥质粉砂岩等4种典型岩组。软岩的发育特征、空间展布形态、崩解特性直接关系到边坡整体稳定性和支护措施的方案设计。在重点研究F3断层、L9、L10、Lc、L11等软带内所发育的几种典型软岩岩组的崩解特性后,获知该类软岩极易吸水,遇水后发生泥化、软化和崩解。通过循环崩解试验,发现工程区内软岩的崩解度与泥质含量和崩解次数具有很好的相关性。同时,根据崩解度与崩解物形态,对软岩进行定性划分,分别定出Ⅴ类崩解岩和5种崩解破坏形式。最后就崩解机理作进一步地深入探讨。该成果为指导类似的工程边坡软岩的崩解性试验研究提供新的思路。 相似文献
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The orthogonal supersegment of the ultraslow-spreading Southwest Indian Ridge at 16°–25°E is characterized by significant along-axis variations of mantle potential temperature. A detailed analysis of multibeam bathymetry,gravity, and magnetic data were performed to investigate its variations in magma supply and crustal accretion process. The results revealed distinct across-axis variations of magma supply. Specifically, the regionally averaged crustal thickness reduced systematically from around 7 Ma to the present, indicating a regionally decreasing magma supply. The crustal structure is asymmetric in regional scale between the conjugate ridge flanks, with the faster-spreading southern flank showing thinner crust and greater degree of tectonic extension. Geodynamic models of mantle melting suggested that the observed variations in axial crustal thickness and major element geochemistry can be adequately explained by an eastward decrease in mantle potential temperature of about40°C beneath the ridge axis. In this work, a synthesized model was proposed to explain the axial variations of magma supply and ridge segmentation stabilities. The existence of large ridge-axis offsets may play important roles in controlling melt supply. Several large ridge-axis offsets in the eastern section(21°–25°E) caused sustained along-axis focusing of magma supply at the centers of eastern ridge segments, enabling quasi-stable segmentation. In contrast, the western section(16°–21°E), which lacks large ridge-axis offsets, is associated with unstable segmentation patterns. 相似文献
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Dramatic decreases in groundwater quality have raised widespread concerns about water supplies and ecological crises in China. In this study, hydrochemistry, stable isotopes, and graphical and multivariate statistical methods are integrated to identify hydrogeochemical processes controlling groundwater quality in the Yuncheng Basin, China. Our results show that groundwater with 21 variables (pH, temperature-T, total dissolved solid, major-trace elements, and stable isotopes) is chemically classified into three distinct clusters: fresh water [C1], brackish-saline water [C2], and saline water [C3]. Groundwater salinization is identified as the prime process in controlling groundwater quality for shallow groundwater and deep groundwater in the lowland areas. Large-scale As, F, or B contaminations found in groundwater are closely related to groundwater salinization, agricultural activity, and the exploration of geothermal water in the area. With respect to the risk of contamination, groundwater in the basin is spatially divided into the following: shallow groundwater with a high risk located in the north side of the Salt Lake, shallow groundwater with a moderate risk, and deep groundwater with a low to moderate risk. Nationally, the increasing demand on groundwater is threatened by a range of environmental and health pressures, including salinization and contaminations of nitrate, As, F, or B. Our study indicates that natural water-rock interactions and hydrogeological conditions are significant factors controlling these contaminations. Systematic management and regulation of existing groundwater resources are required to prevent further deterioration of groundwater resources. Policies should be made and implemented to ensure “green” exploitation of geothermal water. 相似文献
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LI Zan LIU Xiumei CAO DANDan LIU Yuezhong WANG Xubo LIU Jinxiang WANG Zhigang ZHANG Quanqi YU Haiyang 《中国海洋大学学报(英文版)》2018,(5)
Interleukin-1 beta(IL-1β) is a cytokine involved in the control of inflammatory responses.The functions of IL-1β have been extensively studied in many vertebrates.However,few studies focused on the functions of IL-1β in the spotted halibut(Verasper variegatus),an endangered aquatic fish that easily suffers from bacterial and viral infections.We first cloned and sequenced the IL-1β gene from V.variegatus(Vv IL-1β).Its conservative interleukin-1 propeptide and interleukin-1/18 domains corresponding regions,characteristics of the IL-1 protein family and TA-rich motifs relating to inflammatory responses were similar to those of the IL-1β genes from other teleost and mammals.The phylogenetic analysis showed that Vv IL-1β was homologous to the IL-1β gene of other vertebrates.Treatment with pathogen-associated molecular patterns(PAMPs) induced a significant and rapid up-regulation of Vv IL-1β expression in the peripheral blood leukocytes(PBLs),revealing that Vv IL-1β is actively involved in the host immune responses against bacterial and viral pathogens.The expression level of Vv IL-1β was relatively high in the PBLs,gill,and intestine,indicating the immunological function of Vv IL-1β.Vv IL-1β also had interesting expression patterns at specific developmental stages,implying that the IL-1β of flatfishes may have some novel functions during embryonic development and metamorphosis.The 3 D structure prediction also provided information about how Vv IL-1β interacts with its receptor protein.These results suggested that Vv IL-1β may have multiple functions in V.variegatus and provided us valuable information for understanding the novel functions of IL-1β. 相似文献
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吉松铅锌矿位于西藏山南地区错那县吉松村,是扎西康整装勘查区中新近发现的热液脉型铅锌矿床（宋旭波等,2015）。由于矿床整体工作程度较低,目前仅对该矿床的地质特征及矿床成因等方面进行了初步探讨（尹远等,2015;曾凡淼等,2010;余江等,2016）,但对于矿床找矿方向问题研究却极为薄弱,特别是矿床外围找矿潜力评价工作尚未进行,严重阻碍了勘查工作的推进。在近来对于矿床外围开展的地质调查工作中,发现了一系列较好的找矿远景区。本文在综合前人的研究成果基础上,重点探讨吉松铅锌矿外围的化探异常,为在外围找矿的下一步工作提供参考。 相似文献
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Haiyang Yu Liming Jiang Wei Chen Xubo Wang Zhigang Wang Quanqi Zhang 《中国海洋大学学报(英文版)》2010,9(4):365-370
The expressed sequence tags (ESTs) of Japanese flounder, Paralichthys olivaceus, were selected from GenBank to identify simple sequence repeats (SSRs) or microsatellites. A bioinformatic analysis of 11111
ESTs identified 751 SSR-containing ESTs, including 440 dinucleotide, 254 trinucleotide, 53 tetranucleotide, 95 pentanucleotide
and 40 hexanucleotide microsatellites respectively. The CA/TG and GA/TC repeats were the most abundant microsatellites. AT-rich
types were predominant among trinucleotide and tetranucleotide microsatellites. PCR primers were designed to amplify 10 identified
microsatellites loci. The PCR results from eight pairs of primers showed polymorphisms in wild populations. In 30 wild individuals,
the mean observed and expected heterozygosities of these 8 polymorphic SSRs were 0.71 and 0.83 respectively and the average
PIC value was 0.8. These microsatellite markers should prove to be a useful addition to the microsatellite markers that are
now available for this species. 相似文献
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水化学—稳定同位素技术在岩溶水文地质研究中的应用 总被引：3，自引：0，他引：3
水化学—稳定同位素技术在岩溶水系统分析中得到了广泛的应用,尤其是在指示岩溶水文地球化学过程、识别岩溶水补给循环途径、溶质溯源及岩溶水污染监测防控等方面显示了独特的优势,产生了丰富的成果。本文着重阐述了环境稳定同位素δD、δ18O、87Sr/86Sr的工作原理,及水化学—稳定同位素技术在岩溶水文地质研究中的应用。此外,论文还以娘子关泉域和北京西山岩溶水系统为例,介绍了运用水化学—稳定同位素技术分析岩溶水系统补给的思路和方法,展望了该技术在岩溶水文地质和岩溶生态环境领域中的应用前景。 相似文献