4 resultados para Bush

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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本文通过对墨西哥湾Bush Hill 的5个冷泉碳酸盐岩样品和Alaminos Canyon 的1个冷泉碳酸盐岩样品的总有机质含量、可溶有机质含量、饱和烃、芳烃、脂肪酸、δ13C组成分布特征和部分地球化学参数的研究,探讨了冷泉碳酸盐岩中有机质来源、成熟度和沉积环境。 Bush Hill的冷泉碳酸盐岩样品的总有机碳为0.78-9.02%,可溶有机质含量5.77-65.06mg/g。总有机碳达9.02%的GC-B样品高碳数正构烷烃奇偶优势明显,存在荧蒽、芘和苝系列化合物,表明该样品有陆源物质的输入,并明显受深部渗漏原油的影响,其中烷烃的δ13C为-27.64~-32.36‰,正构脂肪酸δ13C为-26.52~-39.99‰,与现代菌藻类及下伏油气藏的δ13C值(-27~-31‰)相似,表明样品中的有机质主体可能来源于深部油气藏。其余4个Bush Hill冷泉碳酸盐岩样品和1个Alaminos Canyon冷泉碳酸盐岩样品正构烷烃的低碳优势明显,而奇偶优势不明显,低碳数分布的环己烷和长链烷基苯,以及三芳甾烷和甲基三芳甾烷的存在,推断这些样品的母质以菌藻类来源为主。 所有分析样品的甾烷成熟度参数C29ββ/(ββ+αα)为0.28-0.40,C2920S/(20S + 20R)为0.42-0.61、及C20-C21三芳孕甾烷TA(Ⅰ)/C26-C28三芳甾烷TA(Ⅱ)为0.49都说明样品的有机质成熟度较低,。 AC深水区AC-E样品UCM隆起不明显,Bush Hill浅水区样品(GC-B、GC-D、GC-F、GC-G,GC-H)UCM隆起均十分明显,这种隆起的形成是因为正烷烃、甚至五环三萜烷遭受生物降解。被微生物降解的正构烷烃与未被降解的环烷烃和支链烷烃等形成不能被溶解的复杂混合物(UCM)。因此,UCM隆起通常被认为是有机质遭受生物降解最直接的证据。深水区AC-E和Bush Hill浅水区GC-F样品中芴、氧芴和硫芴之间的丰度关系为硫芴﹥芴﹥氧芴,表明其为弱氧化-弱还原的沉积环境。具有较负碳同位素组成(-63.95‰ ~ -50.48‰)的异构/反异构脂肪酸是硫酸盐还原细菌的典型生物标志化合物,进一步证实冷泉碳酸盐岩的形成与甲烷缺氧氧化作用有关。 关键词:墨西哥湾 冷泉碳酸盐岩 有机质组成分布 单体烃碳同位素 沉积环境

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ZnO nanoflowers are synthesized on AIN films by solution method. The synthesized nanoflowers are composed of nanorods, which are pyramidal and grow from a central point, thus forming structures that are flower-shaped as a whole. The nanoflowers have two typical morphologies: plate-like and bush-like. The XRD spectrum corresponds to the side planes of the ZnO nanorods made up of the nanoflowers. The micro-Raman spectrum of the ZnO nanoflowers exhibits the E-2 (high) mode and the second order multiple-phonon mode. The photoluminescence spectrum of the ZnO nanoflowers exhibits ultraviolet emission centred at 375 nm and a broad green emission centred at 526 nm.

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用理论分析和典型观测的方法研究了人工油松林系统水土保持功能的叠加效应。结果表明 :与荒坡灌草小流域相比 ,人工油松林系统减小净雨作用明显 ;对两次次降水而言 ,人工油松林系统对径流时间的滞后效应各为荒坡灌草的 2 .5倍和 4 .3倍 ;对径流动能的减小效应分别为 2 5 .0倍和 166.4倍 ;对挟沙能力的减小效应分别为 2 4 .4倍和 163 .3倍。人工油松林系统能改良土壤 ,使其抗冲、抗蚀性能提高 ,此种双向作用使人工油松林发挥了良好的水土保持作用。

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The unique geologic, geomorphic and climatic conditions of southeast Tibet have made the region to develop the multi-style and frequently occurring geologic hazards, especially the collapses and landslides and debris flows along the section of Ranwu-Lulang in Sichuan-Tibet highway. However, most of those geologic hazards have close relationship with the loose accumulations. That is, the loose accumulations are the main carrier of most geologic hazards. Thereof, the huge-thick accumulations along the highway is regarded as the objective in the thesis to study the geologic background, hazarding model and mitigation methods comprehensively, based on the multi-disciplinary theories and former materials. First of all, in the paper, based on field engineering geologic investigations, the genetic type and the characteristics of spatiotemporal distribution of the huge-thick loose accumulations along the highway, have been analysized from the factors of regional geology and geomorphy and climate, as well as the coupling acting of those factors with inoculation and eruption of the loose accumulations geologic hazards. The huge-thick loose accumulations has complex genetic types and specific regulations of spatiotemporal distribution, closely controlled by the outer environment of the region. The accumulations are composed of earth and boulder, with disorder structure and poor sorting, specific forming environments and depositing conditions. And its physical and mechanic properties are greatly distinguished from rock and common earth inland. When Sichuan-Tibet highway was firstly constructed along the north bank of Purlung Tsangpo River, the huge-thick loose accumulations was cut into many high and steep slopes. Through the survey to the cut-slopes and systematic investigation to their failures, the combination of height and angle of the accumulations slope has been obtained. At the same time, the types of genetic structure of those cut-slopes are also analysized and concluded, as well as their failure models. It is studied in the paper that there are piaster, duality, multielement and complexity types in genetic structure, and rip-dump-repose, rip-shear-slip and weathering-flake types in failure models. Moreover, it is briefly introduced present engineering performance methods and techniques dealing with the deformation and failure of the accumulations cut-slope. It is also suggested that several new techniques of slope enforcement and the method of landslide and rockfall avoiding should be applied. The research of high and steep cut-slope along the highway has broadened the acknowledgement of the combination of cut-slope height and angle. Especially, the dissertation also has made the monographic studies about the geologic background and hazarding models and prevention methods of some classic but difficult accumulations geologic hazards. They are: (1) Research of the engineering geologic background of the 102 landslide group and key problems about the project of tunnel. The 102 landslide group is a famous accumulational one composed of glacial tills and glaciofuvial deposit. The tunnel project is a feasible and optional one which can solve the present plight of “sliding after just harnessing” in the 102 section. Based on the glacial geomorphy and its depositing character, distribution of seepage line, a few drillhole materials and some surveying data, the position of contact surface between gneiss and accumulations has been recognized, and the retreating velocities of three different time scales (short, medium and long term) have been approximately calculated, and the weathering thickness of gneiss has also been estimated in the paper. On the basis of above acknowledgement, new engineering geomechnic mode is established. Numerical analysis about the stability of the No.2 landslide is done by way of FLAC program, which supplies the conclusion that the landslide there develops periodically. Thereof, 4 projects of tunnel going through the landslide have been put forwards. Safety distance of the tunnel from clinohefron has been numerically analysized. (2) Research of the geologic setting and disaster model and hazard mitigation of sliding-sand-slope. From the geologic setting of talus cone, it is indicated that the sliding-sand-slope is the process of the re-transportation and re-deposit of sand under the gravity action and from the talus cone. It is the failure of the talus cone essentially. The layering structure of the sliding-sand-slope is discovered. The models of movement and failure of the sliding-sand-slope has been put forwards. The technique, “abamurus+grass-bush fence+degradable culture pan”, is suggested to enforcement and green the sliding-sand-slope. (3) Characteristics and hazarding model and disaster mitigation of debris flow. The sources of solid material of three oversize debris flows have been analysized. It is found that a large amount of moraine existing in the glacial valley and large landslide dam-break are the two important features for oversize debris flow to be taken place. The disaster models of oversize and common debris flows have been generalized respectively. The former model better interpret the event of the Yigong super-large landslide-dam breaking. The features of common debris flow along the highway section, scouring and silting and burying and impacting, are formulated carefully. It is suggested that check dam is a better engineering structure to prevent valley from steeply scouring by debris flow. Moreover, the function of check dam in enforcing the slope is numerically calculated by FLAC program. (4) Songzong ancient ice-dammed lake and its slope stability. The lacustrine profile in Songzong landslide, more than 88 meters thick, is carefully described and measured. The Optical Simulated Luminescence (OSL) ages in the bottom and top of the silty clay layer are 22.5±3.3 kaB.P., 16.1±1.7 kaB.P., respectively. It is indicated by the ages that the lacustrine deposits formed during the Last Glacial Maximum ranging from 25ka B.P. to 15ka B.P. The special characteristics of the lacustrine sediment and the ancient lake line in Songzong basin indicated that the lacustrine sediment is related to the blocking of the Purlung Tsangpo River by the glacier in Last Glacial Maximum from Dongqu valley. The characteristics of the lacustrine profile also indicate that the Songzong ice-dammed lake might run through the Last Glacial Maximum. Two dimensional numerical modeling and analysis are done to simulate the slope stability under the conditions of nature and earthquake by FLAC program. The factor of safety of the lacusrtine slope is 1.04, but it will take place horizontal flow under earthquake activity due to the liquefaction of the 18.33 m silt layer. The realign to prevent the road from landslide is suggested.